1 /* Subroutines shared by all languages that are variants of C.
2    Copyright (C) 1992-2018 Free Software Foundation, Inc.
3 
4 This file is part of GCC.
5 
6 GCC is free software; you can redistribute it and/or modify it under
7 the terms of the GNU General Public License as published by the Free
8 Software Foundation; either version 3, or (at your option) any later
9 version.
10 
11 GCC is distributed in the hope that it will be useful, but WITHOUT ANY
12 WARRANTY; without even the implied warranty of MERCHANTABILITY or
13 FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
14 for more details.
15 
16 You should have received a copy of the GNU General Public License
17 along with GCC; see the file COPYING3.  If not see
18 <http://www.gnu.org/licenses/>.  */
19 
20 #define GCC_C_COMMON_C
21 
22 #include "config.h"
23 #include "system.h"
24 #include "coretypes.h"
25 #include "target.h"
26 #include "function.h"
27 #include "tree.h"
28 #include "memmodel.h"
29 #include "c-common.h"
30 #include "gimple-expr.h"
31 #include "tm_p.h"
32 #include "stringpool.h"
33 #include "cgraph.h"
34 #include "diagnostic.h"
35 #include "intl.h"
36 #include "stor-layout.h"
37 #include "calls.h"
38 #include "attribs.h"
39 #include "varasm.h"
40 #include "trans-mem.h"
41 #include "c-objc.h"
42 #include "common/common-target.h"
43 #include "langhooks.h"
44 #include "tree-inline.h"
45 #include "toplev.h"
46 #include "tree-iterator.h"
47 #include "opts.h"
48 #include "gimplify.h"
49 #include "substring-locations.h"
50 #include "spellcheck.h"
51 #include "selftest.h"
52 
53 cpp_reader *parse_in;		/* Declared in c-pragma.h.  */
54 
55 /* Mode used to build pointers (VOIDmode means ptr_mode).  */
56 
57 machine_mode c_default_pointer_mode = VOIDmode;
58 
59 /* The following symbols are subsumed in the c_global_trees array, and
60    listed here individually for documentation purposes.
61 
62    INTEGER_TYPE and REAL_TYPE nodes for the standard data types.
63 
64 	tree short_integer_type_node;
65 	tree long_integer_type_node;
66 	tree long_long_integer_type_node;
67 
68 	tree short_unsigned_type_node;
69 	tree long_unsigned_type_node;
70 	tree long_long_unsigned_type_node;
71 
72 	tree truthvalue_type_node;
73 	tree truthvalue_false_node;
74 	tree truthvalue_true_node;
75 
76 	tree ptrdiff_type_node;
77 
78 	tree unsigned_char_type_node;
79 	tree signed_char_type_node;
80 	tree wchar_type_node;
81 
82 	tree char16_type_node;
83 	tree char32_type_node;
84 
85 	tree float_type_node;
86 	tree double_type_node;
87 	tree long_double_type_node;
88 
89 	tree complex_integer_type_node;
90 	tree complex_float_type_node;
91 	tree complex_double_type_node;
92 	tree complex_long_double_type_node;
93 
94 	tree dfloat32_type_node;
95 	tree dfloat64_type_node;
96 	tree_dfloat128_type_node;
97 
98 	tree intQI_type_node;
99 	tree intHI_type_node;
100 	tree intSI_type_node;
101 	tree intDI_type_node;
102 	tree intTI_type_node;
103 
104 	tree unsigned_intQI_type_node;
105 	tree unsigned_intHI_type_node;
106 	tree unsigned_intSI_type_node;
107 	tree unsigned_intDI_type_node;
108 	tree unsigned_intTI_type_node;
109 
110 	tree widest_integer_literal_type_node;
111 	tree widest_unsigned_literal_type_node;
112 
113    Nodes for types `void *' and `const void *'.
114 
115 	tree ptr_type_node, const_ptr_type_node;
116 
117    Nodes for types `char *' and `const char *'.
118 
119 	tree string_type_node, const_string_type_node;
120 
121    Type `char[SOMENUMBER]'.
122    Used when an array of char is needed and the size is irrelevant.
123 
124 	tree char_array_type_node;
125 
126    Type `wchar_t[SOMENUMBER]' or something like it.
127    Used when a wide string literal is created.
128 
129 	tree wchar_array_type_node;
130 
131    Type `char16_t[SOMENUMBER]' or something like it.
132    Used when a UTF-16 string literal is created.
133 
134 	tree char16_array_type_node;
135 
136    Type `char32_t[SOMENUMBER]' or something like it.
137    Used when a UTF-32 string literal is created.
138 
139 	tree char32_array_type_node;
140 
141    Type `int ()' -- used for implicit declaration of functions.
142 
143 	tree default_function_type;
144 
145    A VOID_TYPE node, packaged in a TREE_LIST.
146 
147 	tree void_list_node;
148 
149   The lazily created VAR_DECLs for __FUNCTION__, __PRETTY_FUNCTION__,
150   and __func__. (C doesn't generate __FUNCTION__ and__PRETTY_FUNCTION__
151   VAR_DECLS, but C++ does.)
152 
153 	tree function_name_decl_node;
154 	tree pretty_function_name_decl_node;
155 	tree c99_function_name_decl_node;
156 
157   Stack of nested function name VAR_DECLs.
158 
159 	tree saved_function_name_decls;
160 
161 */
162 
163 tree c_global_trees[CTI_MAX];
164 
165 /* Switches common to the C front ends.  */
166 
167 /* Nonzero means don't output line number information.  */
168 
169 char flag_no_line_commands;
170 
171 /* Nonzero causes -E output not to be done, but directives such as
172    #define that have side effects are still obeyed.  */
173 
174 char flag_no_output;
175 
176 /* Nonzero means dump macros in some fashion.  */
177 
178 char flag_dump_macros;
179 
180 /* Nonzero means pass #include lines through to the output.  */
181 
182 char flag_dump_includes;
183 
184 /* Nonzero means process PCH files while preprocessing.  */
185 
186 bool flag_pch_preprocess;
187 
188 /* The file name to which we should write a precompiled header, or
189    NULL if no header will be written in this compile.  */
190 
191 const char *pch_file;
192 
193 /* Nonzero if an ISO standard was selected.  It rejects macros in the
194    user's namespace.  */
195 int flag_iso;
196 
197 /* C/ObjC language option variables.  */
198 
199 
200 /* Nonzero means allow type mismatches in conditional expressions;
201    just make their values `void'.  */
202 
203 int flag_cond_mismatch;
204 
205 /* Nonzero means enable C89 Amendment 1 features.  */
206 
207 int flag_isoc94;
208 
209 /* Nonzero means use the ISO C99 (or C11) dialect of C.  */
210 
211 int flag_isoc99;
212 
213 /* Nonzero means use the ISO C11 dialect of C.  */
214 
215 int flag_isoc11;
216 
217 /* Nonzero means that we have builtin functions, and main is an int.  */
218 
219 int flag_hosted = 1;
220 
221 
222 /* ObjC language option variables.  */
223 
224 
225 /* Tells the compiler that this is a special run.  Do not perform any
226    compiling, instead we are to test some platform dependent features
227    and output a C header file with appropriate definitions.  */
228 
229 int print_struct_values;
230 
231 /* Tells the compiler what is the constant string class for ObjC.  */
232 
233 const char *constant_string_class_name;
234 
235 
236 /* C++ language option variables.  */
237 
238 /* The reference version of the ABI for -Wabi.  */
239 
240 int warn_abi_version = -1;
241 
242 /* Nonzero means generate separate instantiation control files and
243    juggle them at link time.  */
244 
245 int flag_use_repository;
246 
247 /* The C++ dialect being used.  Default set in c_common_post_options.  */
248 
249 enum cxx_dialect cxx_dialect = cxx_unset;
250 
251 /* Maximum template instantiation depth.  This limit exists to limit the
252    time it takes to notice excessively recursive template instantiations.
253 
254    The default is lower than the 1024 recommended by the C++0x standard
255    because G++ runs out of stack before 1024 with highly recursive template
256    argument deduction substitution (g++.dg/cpp0x/enum11.C).  */
257 
258 int max_tinst_depth = 900;
259 
260 /* The elements of `ridpointers' are identifier nodes for the reserved
261    type names and storage classes.  It is indexed by a RID_... value.  */
262 tree *ridpointers;
263 
264 tree (*make_fname_decl) (location_t, tree, int);
265 
266 /* Nonzero means don't warn about problems that occur when the code is
267    executed.  */
268 int c_inhibit_evaluation_warnings;
269 
270 /* Whether we are building a boolean conversion inside
271    convert_for_assignment, or some other late binary operation.  If
272    build_binary_op is called for C (from code shared by C and C++) in
273    this case, then the operands have already been folded and the
274    result will not be folded again, so C_MAYBE_CONST_EXPR should not
275    be generated.  */
276 bool in_late_binary_op;
277 
278 /* Whether lexing has been completed, so subsequent preprocessor
279    errors should use the compiler's input_location.  */
280 bool done_lexing = false;
281 
282 /* Information about how a function name is generated.  */
283 struct fname_var_t
284 {
285   tree *const decl;	/* pointer to the VAR_DECL.  */
286   const unsigned rid;	/* RID number for the identifier.  */
287   const int pretty;	/* How pretty is it? */
288 };
289 
290 /* The three ways of getting then name of the current function.  */
291 
292 const struct fname_var_t fname_vars[] =
293 {
294   /* C99 compliant __func__, must be first.  */
295   {&c99_function_name_decl_node, RID_C99_FUNCTION_NAME, 0},
296   /* GCC __FUNCTION__ compliant.  */
297   {&function_name_decl_node, RID_FUNCTION_NAME, 0},
298   /* GCC __PRETTY_FUNCTION__ compliant.  */
299   {&pretty_function_name_decl_node, RID_PRETTY_FUNCTION_NAME, 1},
300   {NULL, 0, 0},
301 };
302 
303 /* Global visibility options.  */
304 struct visibility_flags visibility_options;
305 
306 static tree check_case_value (location_t, tree);
307 static bool check_case_bounds (location_t, tree, tree, tree *, tree *,
308 			       bool *);
309 
310 
311 static void check_nonnull_arg (void *, tree, unsigned HOST_WIDE_INT);
312 static bool nonnull_check_p (tree, unsigned HOST_WIDE_INT);
313 
314 /* Reserved words.  The third field is a mask: keywords are disabled
315    if they match the mask.
316 
317    Masks for languages:
318    C --std=c89: D_C99 | D_CXXONLY | D_OBJC | D_CXX_OBJC
319    C --std=c99: D_CXXONLY | D_OBJC
320    ObjC is like C except that D_OBJC and D_CXX_OBJC are not set
321    C++ --std=c++98: D_CONLY | D_CXX11 | D_OBJC
322    C++ --std=c++11: D_CONLY | D_OBJC
323    ObjC++ is like C++ except that D_OBJC is not set
324 
325    If -fno-asm is used, D_ASM is added to the mask.  If
326    -fno-gnu-keywords is used, D_EXT is added.  If -fno-asm and C in
327    C89 mode, D_EXT89 is added for both -fno-asm and -fno-gnu-keywords.
328    In C with -Wc++-compat, we warn if D_CXXWARN is set.
329 
330    Note the complication of the D_CXX_OBJC keywords.  These are
331    reserved words such as 'class'.  In C++, 'class' is a reserved
332    word.  In Objective-C++ it is too.  In Objective-C, it is a
333    reserved word too, but only if it follows an '@' sign.
334 */
335 const struct c_common_resword c_common_reswords[] =
336 {
337   { "_Alignas",		RID_ALIGNAS,   D_CONLY },
338   { "_Alignof",		RID_ALIGNOF,   D_CONLY },
339   { "_Atomic",		RID_ATOMIC,    D_CONLY },
340   { "_Bool",		RID_BOOL,      D_CONLY },
341   { "_Complex",		RID_COMPLEX,	0 },
342   { "_Imaginary",	RID_IMAGINARY, D_CONLY },
343   { "_Float16",         RID_FLOAT16,   D_CONLY },
344   { "_Float32",         RID_FLOAT32,   D_CONLY },
345   { "_Float64",         RID_FLOAT64,   D_CONLY },
346   { "_Float128",        RID_FLOAT128,  D_CONLY },
347   { "_Float32x",        RID_FLOAT32X,  D_CONLY },
348   { "_Float64x",        RID_FLOAT64X,  D_CONLY },
349   { "_Float128x",       RID_FLOAT128X, D_CONLY },
350   { "_Decimal32",       RID_DFLOAT32,  D_CONLY | D_EXT },
351   { "_Decimal64",       RID_DFLOAT64,  D_CONLY | D_EXT },
352   { "_Decimal128",      RID_DFLOAT128, D_CONLY | D_EXT },
353   { "_Fract",           RID_FRACT,     D_CONLY | D_EXT },
354   { "_Accum",           RID_ACCUM,     D_CONLY | D_EXT },
355   { "_Sat",             RID_SAT,       D_CONLY | D_EXT },
356   { "_Static_assert",   RID_STATIC_ASSERT, D_CONLY },
357   { "_Noreturn",        RID_NORETURN,  D_CONLY },
358   { "_Generic",         RID_GENERIC,   D_CONLY },
359   { "_Thread_local",    RID_THREAD,    D_CONLY },
360   { "__FUNCTION__",	RID_FUNCTION_NAME, 0 },
361   { "__PRETTY_FUNCTION__", RID_PRETTY_FUNCTION_NAME, 0 },
362   { "__alignof",	RID_ALIGNOF,	0 },
363   { "__alignof__",	RID_ALIGNOF,	0 },
364   { "__asm",		RID_ASM,	0 },
365   { "__asm__",		RID_ASM,	0 },
366   { "__attribute",	RID_ATTRIBUTE,	0 },
367   { "__attribute__",	RID_ATTRIBUTE,	0 },
368   { "__auto_type",	RID_AUTO_TYPE,	D_CONLY },
369   { "__bases",          RID_BASES, D_CXXONLY },
370   { "__builtin_addressof", RID_ADDRESSOF, D_CXXONLY },
371   { "__builtin_call_with_static_chain",
372     RID_BUILTIN_CALL_WITH_STATIC_CHAIN, D_CONLY },
373   { "__builtin_choose_expr", RID_CHOOSE_EXPR, D_CONLY },
374   { "__builtin_complex", RID_BUILTIN_COMPLEX, D_CONLY },
375   { "__builtin_launder", RID_BUILTIN_LAUNDER, D_CXXONLY },
376   { "__builtin_shuffle", RID_BUILTIN_SHUFFLE, 0 },
377   { "__builtin_tgmath", RID_BUILTIN_TGMATH, D_CONLY },
378   { "__builtin_offsetof", RID_OFFSETOF, 0 },
379   { "__builtin_types_compatible_p", RID_TYPES_COMPATIBLE_P, D_CONLY },
380   { "__builtin_va_arg",	RID_VA_ARG,	0 },
381   { "__complex",	RID_COMPLEX,	0 },
382   { "__complex__",	RID_COMPLEX,	0 },
383   { "__const",		RID_CONST,	0 },
384   { "__const__",	RID_CONST,	0 },
385   { "__decltype",       RID_DECLTYPE,   D_CXXONLY },
386   { "__direct_bases",   RID_DIRECT_BASES, D_CXXONLY },
387   { "__extension__",	RID_EXTENSION,	0 },
388   { "__func__",		RID_C99_FUNCTION_NAME, 0 },
389   { "__has_nothrow_assign", RID_HAS_NOTHROW_ASSIGN, D_CXXONLY },
390   { "__has_nothrow_constructor", RID_HAS_NOTHROW_CONSTRUCTOR, D_CXXONLY },
391   { "__has_nothrow_copy", RID_HAS_NOTHROW_COPY, D_CXXONLY },
392   { "__has_trivial_assign", RID_HAS_TRIVIAL_ASSIGN, D_CXXONLY },
393   { "__has_trivial_constructor", RID_HAS_TRIVIAL_CONSTRUCTOR, D_CXXONLY },
394   { "__has_trivial_copy", RID_HAS_TRIVIAL_COPY, D_CXXONLY },
395   { "__has_trivial_destructor", RID_HAS_TRIVIAL_DESTRUCTOR, D_CXXONLY },
396   { "__has_unique_object_representations", RID_HAS_UNIQUE_OBJ_REPRESENTATIONS,
397 					D_CXXONLY },
398   { "__has_virtual_destructor", RID_HAS_VIRTUAL_DESTRUCTOR, D_CXXONLY },
399   { "__imag",		RID_IMAGPART,	0 },
400   { "__imag__",		RID_IMAGPART,	0 },
401   { "__inline",		RID_INLINE,	0 },
402   { "__inline__",	RID_INLINE,	0 },
403   { "__is_abstract",	RID_IS_ABSTRACT, D_CXXONLY },
404   { "__is_aggregate",	RID_IS_AGGREGATE, D_CXXONLY },
405   { "__is_base_of",	RID_IS_BASE_OF, D_CXXONLY },
406   { "__is_class",	RID_IS_CLASS,	D_CXXONLY },
407   { "__is_empty",	RID_IS_EMPTY,	D_CXXONLY },
408   { "__is_enum",	RID_IS_ENUM,	D_CXXONLY },
409   { "__is_final",	RID_IS_FINAL,	D_CXXONLY },
410   { "__is_literal_type", RID_IS_LITERAL_TYPE, D_CXXONLY },
411   { "__is_pod",		RID_IS_POD,	D_CXXONLY },
412   { "__is_polymorphic",	RID_IS_POLYMORPHIC, D_CXXONLY },
413   { "__is_same_as",     RID_IS_SAME_AS, D_CXXONLY },
414   { "__is_standard_layout", RID_IS_STD_LAYOUT, D_CXXONLY },
415   { "__is_trivial",     RID_IS_TRIVIAL, D_CXXONLY },
416   { "__is_trivially_assignable", RID_IS_TRIVIALLY_ASSIGNABLE, D_CXXONLY },
417   { "__is_trivially_constructible", RID_IS_TRIVIALLY_CONSTRUCTIBLE, D_CXXONLY },
418   { "__is_trivially_copyable", RID_IS_TRIVIALLY_COPYABLE, D_CXXONLY },
419   { "__is_union",	RID_IS_UNION,	D_CXXONLY },
420   { "__label__",	RID_LABEL,	0 },
421   { "__null",		RID_NULL,	0 },
422   { "__real",		RID_REALPART,	0 },
423   { "__real__",		RID_REALPART,	0 },
424   { "__restrict",	RID_RESTRICT,	0 },
425   { "__restrict__",	RID_RESTRICT,	0 },
426   { "__signed",		RID_SIGNED,	0 },
427   { "__signed__",	RID_SIGNED,	0 },
428   { "__thread",		RID_THREAD,	0 },
429   { "__transaction_atomic", RID_TRANSACTION_ATOMIC, 0 },
430   { "__transaction_relaxed", RID_TRANSACTION_RELAXED, 0 },
431   { "__transaction_cancel", RID_TRANSACTION_CANCEL, 0 },
432   { "__typeof",		RID_TYPEOF,	0 },
433   { "__typeof__",	RID_TYPEOF,	0 },
434   { "__underlying_type", RID_UNDERLYING_TYPE, D_CXXONLY },
435   { "__volatile",	RID_VOLATILE,	0 },
436   { "__volatile__",	RID_VOLATILE,	0 },
437   { "__GIMPLE",		RID_GIMPLE,	D_CONLY },
438   { "__PHI",		RID_PHI,	D_CONLY },
439   { "__RTL",		RID_RTL,	D_CONLY },
440   { "alignas",		RID_ALIGNAS,	D_CXXONLY | D_CXX11 | D_CXXWARN },
441   { "alignof",		RID_ALIGNOF,	D_CXXONLY | D_CXX11 | D_CXXWARN },
442   { "asm",		RID_ASM,	D_ASM },
443   { "auto",		RID_AUTO,	0 },
444   { "bool",		RID_BOOL,	D_CXXONLY | D_CXXWARN },
445   { "break",		RID_BREAK,	0 },
446   { "case",		RID_CASE,	0 },
447   { "catch",		RID_CATCH,	D_CXX_OBJC | D_CXXWARN },
448   { "char",		RID_CHAR,	0 },
449   { "char16_t",		RID_CHAR16,	D_CXXONLY | D_CXX11 | D_CXXWARN },
450   { "char32_t",		RID_CHAR32,	D_CXXONLY | D_CXX11 | D_CXXWARN },
451   { "class",		RID_CLASS,	D_CXX_OBJC | D_CXXWARN },
452   { "const",		RID_CONST,	0 },
453   { "constexpr",	RID_CONSTEXPR,	D_CXXONLY | D_CXX11 | D_CXXWARN },
454   { "const_cast",	RID_CONSTCAST,	D_CXXONLY | D_CXXWARN },
455   { "continue",		RID_CONTINUE,	0 },
456   { "decltype",         RID_DECLTYPE,   D_CXXONLY | D_CXX11 | D_CXXWARN },
457   { "default",		RID_DEFAULT,	0 },
458   { "delete",		RID_DELETE,	D_CXXONLY | D_CXXWARN },
459   { "do",		RID_DO,		0 },
460   { "double",		RID_DOUBLE,	0 },
461   { "dynamic_cast",	RID_DYNCAST,	D_CXXONLY | D_CXXWARN },
462   { "else",		RID_ELSE,	0 },
463   { "enum",		RID_ENUM,	0 },
464   { "explicit",		RID_EXPLICIT,	D_CXXONLY | D_CXXWARN },
465   { "export",		RID_EXPORT,	D_CXXONLY | D_CXXWARN },
466   { "extern",		RID_EXTERN,	0 },
467   { "false",		RID_FALSE,	D_CXXONLY | D_CXXWARN },
468   { "float",		RID_FLOAT,	0 },
469   { "for",		RID_FOR,	0 },
470   { "friend",		RID_FRIEND,	D_CXXONLY | D_CXXWARN },
471   { "goto",		RID_GOTO,	0 },
472   { "if",		RID_IF,		0 },
473   { "inline",		RID_INLINE,	D_EXT89 },
474   { "int",		RID_INT,	0 },
475   { "long",		RID_LONG,	0 },
476   { "mutable",		RID_MUTABLE,	D_CXXONLY | D_CXXWARN },
477   { "namespace",	RID_NAMESPACE,	D_CXXONLY | D_CXXWARN },
478   { "new",		RID_NEW,	D_CXXONLY | D_CXXWARN },
479   { "noexcept",		RID_NOEXCEPT,	D_CXXONLY | D_CXX11 | D_CXXWARN },
480   { "nullptr",		RID_NULLPTR,	D_CXXONLY | D_CXX11 | D_CXXWARN },
481   { "operator",		RID_OPERATOR,	D_CXXONLY | D_CXXWARN },
482   { "private",		RID_PRIVATE,	D_CXX_OBJC | D_CXXWARN },
483   { "protected",	RID_PROTECTED,	D_CXX_OBJC | D_CXXWARN },
484   { "public",		RID_PUBLIC,	D_CXX_OBJC | D_CXXWARN },
485   { "register",		RID_REGISTER,	0 },
486   { "reinterpret_cast",	RID_REINTCAST,	D_CXXONLY | D_CXXWARN },
487   { "restrict",		RID_RESTRICT,	D_CONLY | D_C99 },
488   { "return",		RID_RETURN,	0 },
489   { "short",		RID_SHORT,	0 },
490   { "signed",		RID_SIGNED,	0 },
491   { "sizeof",		RID_SIZEOF,	0 },
492   { "static",		RID_STATIC,	0 },
493   { "static_assert",    RID_STATIC_ASSERT, D_CXXONLY | D_CXX11 | D_CXXWARN },
494   { "static_cast",	RID_STATCAST,	D_CXXONLY | D_CXXWARN },
495   { "struct",		RID_STRUCT,	0 },
496   { "switch",		RID_SWITCH,	0 },
497   { "template",		RID_TEMPLATE,	D_CXXONLY | D_CXXWARN },
498   { "this",		RID_THIS,	D_CXXONLY | D_CXXWARN },
499   { "thread_local",	RID_THREAD,	D_CXXONLY | D_CXX11 | D_CXXWARN },
500   { "throw",		RID_THROW,	D_CXX_OBJC | D_CXXWARN },
501   { "true",		RID_TRUE,	D_CXXONLY | D_CXXWARN },
502   { "try",		RID_TRY,	D_CXX_OBJC | D_CXXWARN },
503   { "typedef",		RID_TYPEDEF,	0 },
504   { "typename",		RID_TYPENAME,	D_CXXONLY | D_CXXWARN },
505   { "typeid",		RID_TYPEID,	D_CXXONLY | D_CXXWARN },
506   { "typeof",		RID_TYPEOF,	D_ASM | D_EXT },
507   { "union",		RID_UNION,	0 },
508   { "unsigned",		RID_UNSIGNED,	0 },
509   { "using",		RID_USING,	D_CXXONLY | D_CXXWARN },
510   { "virtual",		RID_VIRTUAL,	D_CXXONLY | D_CXXWARN },
511   { "void",		RID_VOID,	0 },
512   { "volatile",		RID_VOLATILE,	0 },
513   { "wchar_t",		RID_WCHAR,	D_CXXONLY },
514   { "while",		RID_WHILE,	0 },
515   { "__is_assignable", RID_IS_ASSIGNABLE, D_CXXONLY },
516   { "__is_constructible", RID_IS_CONSTRUCTIBLE, D_CXXONLY },
517 
518   /* C++ transactional memory.  */
519   { "synchronized",	RID_SYNCHRONIZED, D_CXX_OBJC | D_TRANSMEM },
520   { "atomic_noexcept",	RID_ATOMIC_NOEXCEPT, D_CXXONLY | D_TRANSMEM },
521   { "atomic_cancel",	RID_ATOMIC_CANCEL, D_CXXONLY | D_TRANSMEM },
522   { "atomic_commit",	RID_TRANSACTION_ATOMIC, D_CXXONLY | D_TRANSMEM },
523 
524   /* Concepts-related keywords */
525   { "concept",		RID_CONCEPT,	D_CXX_CONCEPTS_FLAGS | D_CXXWARN },
526   { "requires", 	RID_REQUIRES,	D_CXX_CONCEPTS_FLAGS | D_CXXWARN },
527 
528   /* These Objective-C keywords are recognized only immediately after
529      an '@'.  */
530   { "compatibility_alias", RID_AT_ALIAS,	D_OBJC },
531   { "defs",		RID_AT_DEFS,		D_OBJC },
532   { "encode",		RID_AT_ENCODE,		D_OBJC },
533   { "end",		RID_AT_END,		D_OBJC },
534   { "implementation",	RID_AT_IMPLEMENTATION,	D_OBJC },
535   { "interface",	RID_AT_INTERFACE,	D_OBJC },
536   { "protocol",		RID_AT_PROTOCOL,	D_OBJC },
537   { "selector",		RID_AT_SELECTOR,	D_OBJC },
538   { "finally",		RID_AT_FINALLY,		D_OBJC },
539   { "optional",		RID_AT_OPTIONAL,	D_OBJC },
540   { "required",		RID_AT_REQUIRED,	D_OBJC },
541   { "property",		RID_AT_PROPERTY,	D_OBJC },
542   { "package",		RID_AT_PACKAGE,		D_OBJC },
543   { "synthesize",	RID_AT_SYNTHESIZE,	D_OBJC },
544   { "dynamic",		RID_AT_DYNAMIC,		D_OBJC },
545   /* These are recognized only in protocol-qualifier context
546      (see above) */
547   { "bycopy",		RID_BYCOPY,		D_OBJC },
548   { "byref",		RID_BYREF,		D_OBJC },
549   { "in",		RID_IN,			D_OBJC },
550   { "inout",		RID_INOUT,		D_OBJC },
551   { "oneway",		RID_ONEWAY,		D_OBJC },
552   { "out",		RID_OUT,		D_OBJC },
553   /* These are recognized inside a property attribute list */
554   { "assign",	        RID_ASSIGN,		D_OBJC },
555   { "copy",	        RID_COPY,		D_OBJC },
556   { "getter",		RID_GETTER,		D_OBJC },
557   { "nonatomic",	RID_NONATOMIC,		D_OBJC },
558   { "readonly",		RID_READONLY,		D_OBJC },
559   { "readwrite",	RID_READWRITE,		D_OBJC },
560   { "retain",	        RID_RETAIN,		D_OBJC },
561   { "setter",		RID_SETTER,		D_OBJC },
562 };
563 
564 const unsigned int num_c_common_reswords =
565   sizeof c_common_reswords / sizeof (struct c_common_resword);
566 
567 /* Return identifier for address space AS.  */
568 
569 const char *
570 c_addr_space_name (addr_space_t as)
571 {
572   int rid = RID_FIRST_ADDR_SPACE + as;
573   gcc_assert (ridpointers [rid]);
574   return IDENTIFIER_POINTER (ridpointers [rid]);
575 }
576 
577 /* Push current bindings for the function name VAR_DECLS.  */
578 
579 void
580 start_fname_decls (void)
581 {
582   unsigned ix;
583   tree saved = NULL_TREE;
584 
585   for (ix = 0; fname_vars[ix].decl; ix++)
586     {
587       tree decl = *fname_vars[ix].decl;
588 
589       if (decl)
590 	{
591 	  saved = tree_cons (decl, build_int_cst (integer_type_node, ix),
592 			     saved);
593 	  *fname_vars[ix].decl = NULL_TREE;
594 	}
595     }
596   if (saved || saved_function_name_decls)
597     /* Normally they'll have been NULL, so only push if we've got a
598        stack, or they are non-NULL.  */
599     saved_function_name_decls = tree_cons (saved, NULL_TREE,
600 					   saved_function_name_decls);
601 }
602 
603 /* Finish up the current bindings, adding them into the current function's
604    statement tree.  This must be done _before_ finish_stmt_tree is called.
605    If there is no current function, we must be at file scope and no statements
606    are involved. Pop the previous bindings.  */
607 
608 void
609 finish_fname_decls (void)
610 {
611   unsigned ix;
612   tree stmts = NULL_TREE;
613   tree stack = saved_function_name_decls;
614 
615   for (; stack && TREE_VALUE (stack); stack = TREE_CHAIN (stack))
616     append_to_statement_list (TREE_VALUE (stack), &stmts);
617 
618   if (stmts)
619     {
620       tree *bodyp = &DECL_SAVED_TREE (current_function_decl);
621 
622       if (TREE_CODE (*bodyp) == BIND_EXPR)
623 	bodyp = &BIND_EXPR_BODY (*bodyp);
624 
625       append_to_statement_list_force (*bodyp, &stmts);
626       *bodyp = stmts;
627     }
628 
629   for (ix = 0; fname_vars[ix].decl; ix++)
630     *fname_vars[ix].decl = NULL_TREE;
631 
632   if (stack)
633     {
634       /* We had saved values, restore them.  */
635       tree saved;
636 
637       for (saved = TREE_PURPOSE (stack); saved; saved = TREE_CHAIN (saved))
638 	{
639 	  tree decl = TREE_PURPOSE (saved);
640 	  unsigned ix = TREE_INT_CST_LOW (TREE_VALUE (saved));
641 
642 	  *fname_vars[ix].decl = decl;
643 	}
644       stack = TREE_CHAIN (stack);
645     }
646   saved_function_name_decls = stack;
647 }
648 
649 /* Return the text name of the current function, suitably prettified
650    by PRETTY_P.  Return string must be freed by caller.  */
651 
652 const char *
653 fname_as_string (int pretty_p)
654 {
655   const char *name = "top level";
656   char *namep;
657   int vrb = 2, len;
658   cpp_string cstr = { 0, 0 }, strname;
659 
660   if (!pretty_p)
661     {
662       name = "";
663       vrb = 0;
664     }
665 
666   if (current_function_decl)
667     name = lang_hooks.decl_printable_name (current_function_decl, vrb);
668 
669   len = strlen (name) + 3; /* Two for '"'s.  One for NULL.  */
670 
671   namep = XNEWVEC (char, len);
672   snprintf (namep, len, "\"%s\"", name);
673   strname.text = (unsigned char *) namep;
674   strname.len = len - 1;
675 
676   if (cpp_interpret_string (parse_in, &strname, 1, &cstr, CPP_STRING))
677     {
678       XDELETEVEC (namep);
679       return (const char *) cstr.text;
680     }
681 
682   return namep;
683 }
684 
685 /* Return the VAR_DECL for a const char array naming the current
686    function. If the VAR_DECL has not yet been created, create it
687    now. RID indicates how it should be formatted and IDENTIFIER_NODE
688    ID is its name (unfortunately C and C++ hold the RID values of
689    keywords in different places, so we can't derive RID from ID in
690    this language independent code. LOC is the location of the
691    function.  */
692 
693 tree
694 fname_decl (location_t loc, unsigned int rid, tree id)
695 {
696   unsigned ix;
697   tree decl = NULL_TREE;
698 
699   for (ix = 0; fname_vars[ix].decl; ix++)
700     if (fname_vars[ix].rid == rid)
701       break;
702 
703   decl = *fname_vars[ix].decl;
704   if (!decl)
705     {
706       /* If a tree is built here, it would normally have the lineno of
707 	 the current statement.  Later this tree will be moved to the
708 	 beginning of the function and this line number will be wrong.
709 	 To avoid this problem set the lineno to 0 here; that prevents
710 	 it from appearing in the RTL.  */
711       tree stmts;
712       location_t saved_location = input_location;
713       input_location = UNKNOWN_LOCATION;
714 
715       stmts = push_stmt_list ();
716       decl = (*make_fname_decl) (loc, id, fname_vars[ix].pretty);
717       stmts = pop_stmt_list (stmts);
718       if (!IS_EMPTY_STMT (stmts))
719 	saved_function_name_decls
720 	  = tree_cons (decl, stmts, saved_function_name_decls);
721       *fname_vars[ix].decl = decl;
722       input_location = saved_location;
723     }
724   if (!ix && !current_function_decl)
725     pedwarn (loc, 0, "%qD is not defined outside of function scope", decl);
726 
727   return decl;
728 }
729 
730 /* Given a STRING_CST, give it a suitable array-of-chars data type.  */
731 
732 tree
733 fix_string_type (tree value)
734 {
735   int length = TREE_STRING_LENGTH (value);
736   int nchars;
737   tree e_type, i_type, a_type;
738 
739   /* Compute the number of elements, for the array type.  */
740   if (TREE_TYPE (value) == char_array_type_node || !TREE_TYPE (value))
741     {
742       nchars = length;
743       e_type = char_type_node;
744     }
745   else if (TREE_TYPE (value) == char16_array_type_node)
746     {
747       nchars = length / (TYPE_PRECISION (char16_type_node) / BITS_PER_UNIT);
748       e_type = char16_type_node;
749     }
750   else if (TREE_TYPE (value) == char32_array_type_node)
751     {
752       nchars = length / (TYPE_PRECISION (char32_type_node) / BITS_PER_UNIT);
753       e_type = char32_type_node;
754     }
755   else
756     {
757       nchars = length / (TYPE_PRECISION (wchar_type_node) / BITS_PER_UNIT);
758       e_type = wchar_type_node;
759     }
760 
761   /* C89 2.2.4.1, C99 5.2.4.1 (Translation limits).  The analogous
762      limit in C++98 Annex B is very large (65536) and is not normative,
763      so we do not diagnose it (warn_overlength_strings is forced off
764      in c_common_post_options).  */
765   if (warn_overlength_strings)
766     {
767       const int nchars_max = flag_isoc99 ? 4095 : 509;
768       const int relevant_std = flag_isoc99 ? 99 : 90;
769       if (nchars - 1 > nchars_max)
770 	/* Translators: The %d after 'ISO C' will be 90 or 99.  Do not
771 	   separate the %d from the 'C'.  'ISO' should not be
772 	   translated, but it may be moved after 'C%d' in languages
773 	   where modifiers follow nouns.  */
774 	pedwarn (input_location, OPT_Woverlength_strings,
775 		 "string length %qd is greater than the length %qd "
776 		 "ISO C%d compilers are required to support",
777 		 nchars - 1, nchars_max, relevant_std);
778     }
779 
780   /* Create the array type for the string constant.  The ISO C++
781      standard says that a string literal has type `const char[N]' or
782      `const wchar_t[N]'.  We use the same logic when invoked as a C
783      front-end with -Wwrite-strings.
784      ??? We should change the type of an expression depending on the
785      state of a warning flag.  We should just be warning -- see how
786      this is handled in the C++ front-end for the deprecated implicit
787      conversion from string literals to `char*' or `wchar_t*'.
788 
789      The C++ front end relies on TYPE_MAIN_VARIANT of a cv-qualified
790      array type being the unqualified version of that type.
791      Therefore, if we are constructing an array of const char, we must
792      construct the matching unqualified array type first.  The C front
793      end does not require this, but it does no harm, so we do it
794      unconditionally.  */
795   i_type = build_index_type (size_int (nchars - 1));
796   a_type = build_array_type (e_type, i_type);
797   if (c_dialect_cxx() || warn_write_strings)
798     a_type = c_build_qualified_type (a_type, TYPE_QUAL_CONST);
799 
800   TREE_TYPE (value) = a_type;
801   TREE_CONSTANT (value) = 1;
802   TREE_READONLY (value) = 1;
803   TREE_STATIC (value) = 1;
804   return value;
805 }
806 
807 /* Given a string of type STRING_TYPE, determine what kind of string
808    token would give an equivalent execution encoding: CPP_STRING,
809    CPP_STRING16, or CPP_STRING32.  Return CPP_OTHER in case of error.
810    This may not be exactly the string token type that initially created
811    the string, since CPP_WSTRING is indistinguishable from the 16/32 bit
812    string type at this point.
813 
814    This effectively reverses part of the logic in lex_string and
815    fix_string_type.  */
816 
817 static enum cpp_ttype
818 get_cpp_ttype_from_string_type (tree string_type)
819 {
820   gcc_assert (string_type);
821   if (TREE_CODE (string_type) == POINTER_TYPE)
822     string_type = TREE_TYPE (string_type);
823 
824   if (TREE_CODE (string_type) != ARRAY_TYPE)
825     return CPP_OTHER;
826 
827   tree element_type = TREE_TYPE (string_type);
828   if (TREE_CODE (element_type) != INTEGER_TYPE)
829     return CPP_OTHER;
830 
831   int bits_per_character = TYPE_PRECISION (element_type);
832   switch (bits_per_character)
833     {
834     case 8:
835       return CPP_STRING;  /* It could have also been CPP_UTF8STRING.  */
836     case 16:
837       return CPP_STRING16;
838     case 32:
839       return CPP_STRING32;
840     }
841 
842   return CPP_OTHER;
843 }
844 
845 /* The global record of string concatentations, for use in
846    extracting locations within string literals.  */
847 
848 GTY(()) string_concat_db *g_string_concat_db;
849 
850 /* Implementation of LANG_HOOKS_GET_SUBSTRING_LOCATION.  */
851 
852 const char *
853 c_get_substring_location (const substring_loc &substr_loc,
854 			  location_t *out_loc)
855 {
856   enum cpp_ttype tok_type
857     = get_cpp_ttype_from_string_type (substr_loc.get_string_type ());
858   if (tok_type == CPP_OTHER)
859     return "unrecognized string type";
860 
861   return get_source_location_for_substring (parse_in, g_string_concat_db,
862 					    substr_loc.get_fmt_string_loc (),
863 					    tok_type,
864 					    substr_loc.get_caret_idx (),
865 					    substr_loc.get_start_idx (),
866 					    substr_loc.get_end_idx (),
867 					    out_loc);
868 }
869 
870 
871 /* Return true iff T is a boolean promoted to int.  */
872 
873 bool
874 bool_promoted_to_int_p (tree t)
875 {
876   return (CONVERT_EXPR_P (t)
877 	  && TREE_TYPE (t) == integer_type_node
878 	  && TREE_CODE (TREE_TYPE (TREE_OPERAND (t, 0))) == BOOLEAN_TYPE);
879 }
880 
881 /* vector_targets_convertible_p is used for vector pointer types.  The
882    callers perform various checks that the qualifiers are satisfactory,
883    while OTOH vector_targets_convertible_p ignores the number of elements
884    in the vectors.  That's fine with vector pointers as we can consider,
885    say, a vector of 8 elements as two consecutive vectors of 4 elements,
886    and that does not require and conversion of the pointer values.
887    In contrast, vector_types_convertible_p and
888    vector_types_compatible_elements_p are used for vector value types.  */
889 /* True if pointers to distinct types T1 and T2 can be converted to
890    each other without an explicit cast.  Only returns true for opaque
891    vector types.  */
892 bool
893 vector_targets_convertible_p (const_tree t1, const_tree t2)
894 {
895   if (VECTOR_TYPE_P (t1) && VECTOR_TYPE_P (t2)
896       && (TYPE_VECTOR_OPAQUE (t1) || TYPE_VECTOR_OPAQUE (t2))
897       && tree_int_cst_equal (TYPE_SIZE (t1), TYPE_SIZE (t2)))
898     return true;
899 
900   return false;
901 }
902 
903 /* vector_types_convertible_p is used for vector value types.
904    It could in principle call vector_targets_convertible_p as a subroutine,
905    but then the check for vector type would be duplicated with its callers,
906    and also the purpose of vector_targets_convertible_p would become
907    muddled.
908    Where vector_types_convertible_p returns true, a conversion might still be
909    needed to make the types match.
910    In contrast, vector_targets_convertible_p is used for vector pointer
911    values, and vector_types_compatible_elements_p is used specifically
912    in the context for binary operators, as a check if use is possible without
913    conversion.  */
914 /* True if vector types T1 and T2 can be converted to each other
915    without an explicit cast.  If EMIT_LAX_NOTE is true, and T1 and T2
916    can only be converted with -flax-vector-conversions yet that is not
917    in effect, emit a note telling the user about that option if such
918    a note has not previously been emitted.  */
919 bool
920 vector_types_convertible_p (const_tree t1, const_tree t2, bool emit_lax_note)
921 {
922   static bool emitted_lax_note = false;
923   bool convertible_lax;
924 
925   if ((TYPE_VECTOR_OPAQUE (t1) || TYPE_VECTOR_OPAQUE (t2))
926       && tree_int_cst_equal (TYPE_SIZE (t1), TYPE_SIZE (t2)))
927     return true;
928 
929   convertible_lax =
930     (tree_int_cst_equal (TYPE_SIZE (t1), TYPE_SIZE (t2))
931      && (TREE_CODE (TREE_TYPE (t1)) != REAL_TYPE
932 	 || known_eq (TYPE_VECTOR_SUBPARTS (t1),
933 		      TYPE_VECTOR_SUBPARTS (t2)))
934      && (INTEGRAL_TYPE_P (TREE_TYPE (t1))
935 	 == INTEGRAL_TYPE_P (TREE_TYPE (t2))));
936 
937   if (!convertible_lax || flag_lax_vector_conversions)
938     return convertible_lax;
939 
940   if (known_eq (TYPE_VECTOR_SUBPARTS (t1), TYPE_VECTOR_SUBPARTS (t2))
941       && lang_hooks.types_compatible_p (TREE_TYPE (t1), TREE_TYPE (t2)))
942     return true;
943 
944   if (emit_lax_note && !emitted_lax_note)
945     {
946       emitted_lax_note = true;
947       inform (input_location, "use -flax-vector-conversions to permit "
948               "conversions between vectors with differing "
949               "element types or numbers of subparts");
950     }
951 
952   return false;
953 }
954 
955 /* Build a VEC_PERM_EXPR if V0, V1 and MASK are not error_mark_nodes
956    and have vector types, V0 has the same type as V1, and the number of
957    elements of V0, V1, MASK is the same.
958 
959    In case V1 is a NULL_TREE it is assumed that __builtin_shuffle was
960    called with two arguments.  In this case implementation passes the
961    first argument twice in order to share the same tree code.  This fact
962    could enable the mask-values being twice the vector length.  This is
963    an implementation accident and this semantics is not guaranteed to
964    the user.  */
965 tree
966 c_build_vec_perm_expr (location_t loc, tree v0, tree v1, tree mask,
967 		       bool complain)
968 {
969   tree ret;
970   bool wrap = true;
971   bool maybe_const = false;
972   bool two_arguments = false;
973 
974   if (v1 == NULL_TREE)
975     {
976       two_arguments = true;
977       v1 = v0;
978     }
979 
980   if (v0 == error_mark_node || v1 == error_mark_node
981       || mask == error_mark_node)
982     return error_mark_node;
983 
984   if (!VECTOR_INTEGER_TYPE_P (TREE_TYPE (mask)))
985     {
986       if (complain)
987 	error_at (loc, "__builtin_shuffle last argument must "
988 		       "be an integer vector");
989       return error_mark_node;
990     }
991 
992   if (!VECTOR_TYPE_P (TREE_TYPE (v0))
993       || !VECTOR_TYPE_P (TREE_TYPE (v1)))
994     {
995       if (complain)
996 	error_at (loc, "__builtin_shuffle arguments must be vectors");
997       return error_mark_node;
998     }
999 
1000   if (TYPE_MAIN_VARIANT (TREE_TYPE (v0)) != TYPE_MAIN_VARIANT (TREE_TYPE (v1)))
1001     {
1002       if (complain)
1003 	error_at (loc, "__builtin_shuffle argument vectors must be of "
1004 		       "the same type");
1005       return error_mark_node;
1006     }
1007 
1008   if (maybe_ne (TYPE_VECTOR_SUBPARTS (TREE_TYPE (v0)),
1009 		TYPE_VECTOR_SUBPARTS (TREE_TYPE (mask)))
1010       && maybe_ne (TYPE_VECTOR_SUBPARTS (TREE_TYPE (v1)),
1011 		   TYPE_VECTOR_SUBPARTS (TREE_TYPE (mask))))
1012     {
1013       if (complain)
1014 	error_at (loc, "__builtin_shuffle number of elements of the "
1015 		       "argument vector(s) and the mask vector should "
1016 		       "be the same");
1017       return error_mark_node;
1018     }
1019 
1020   if (GET_MODE_BITSIZE (SCALAR_TYPE_MODE (TREE_TYPE (TREE_TYPE (v0))))
1021       != GET_MODE_BITSIZE (SCALAR_TYPE_MODE (TREE_TYPE (TREE_TYPE (mask)))))
1022     {
1023       if (complain)
1024 	error_at (loc, "__builtin_shuffle argument vector(s) inner type "
1025 		       "must have the same size as inner type of the mask");
1026       return error_mark_node;
1027     }
1028 
1029   if (!c_dialect_cxx ())
1030     {
1031       /* Avoid C_MAYBE_CONST_EXPRs inside VEC_PERM_EXPR.  */
1032       v0 = c_fully_fold (v0, false, &maybe_const);
1033       wrap &= maybe_const;
1034 
1035       if (two_arguments)
1036         v1 = v0 = save_expr (v0);
1037       else
1038         {
1039           v1 = c_fully_fold (v1, false, &maybe_const);
1040           wrap &= maybe_const;
1041         }
1042 
1043       mask = c_fully_fold (mask, false, &maybe_const);
1044       wrap &= maybe_const;
1045     }
1046   else if (two_arguments)
1047     v1 = v0 = save_expr (v0);
1048 
1049   ret = build3_loc (loc, VEC_PERM_EXPR, TREE_TYPE (v0), v0, v1, mask);
1050 
1051   if (!c_dialect_cxx () && !wrap)
1052     ret = c_wrap_maybe_const (ret, true);
1053 
1054   return ret;
1055 }
1056 
1057 /* Like tree.c:get_narrower, but retain conversion from C++0x scoped enum
1058    to integral type.  */
1059 
1060 tree
1061 c_common_get_narrower (tree op, int *unsignedp_ptr)
1062 {
1063   op = get_narrower (op, unsignedp_ptr);
1064 
1065   if (TREE_CODE (TREE_TYPE (op)) == ENUMERAL_TYPE
1066       && ENUM_IS_SCOPED (TREE_TYPE (op)))
1067     {
1068       /* C++0x scoped enumerations don't implicitly convert to integral
1069 	 type; if we stripped an explicit conversion to a larger type we
1070 	 need to replace it so common_type will still work.  */
1071       tree type = c_common_type_for_size (TYPE_PRECISION (TREE_TYPE (op)),
1072 					  TYPE_UNSIGNED (TREE_TYPE (op)));
1073       op = fold_convert (type, op);
1074     }
1075   return op;
1076 }
1077 
1078 /* This is a helper function of build_binary_op.
1079 
1080    For certain operations if both args were extended from the same
1081    smaller type, do the arithmetic in that type and then extend.
1082 
1083    BITWISE indicates a bitwise operation.
1084    For them, this optimization is safe only if
1085    both args are zero-extended or both are sign-extended.
1086    Otherwise, we might change the result.
1087    Eg, (short)-1 | (unsigned short)-1 is (int)-1
1088    but calculated in (unsigned short) it would be (unsigned short)-1.
1089 */
1090 tree
1091 shorten_binary_op (tree result_type, tree op0, tree op1, bool bitwise)
1092 {
1093   int unsigned0, unsigned1;
1094   tree arg0, arg1;
1095   int uns;
1096   tree type;
1097 
1098   /* Cast OP0 and OP1 to RESULT_TYPE.  Doing so prevents
1099      excessive narrowing when we call get_narrower below.  For
1100      example, suppose that OP0 is of unsigned int extended
1101      from signed char and that RESULT_TYPE is long long int.
1102      If we explicitly cast OP0 to RESULT_TYPE, OP0 would look
1103      like
1104 
1105      (long long int) (unsigned int) signed_char
1106 
1107      which get_narrower would narrow down to
1108 
1109      (unsigned int) signed char
1110 
1111      If we do not cast OP0 first, get_narrower would return
1112      signed_char, which is inconsistent with the case of the
1113      explicit cast.  */
1114   op0 = convert (result_type, op0);
1115   op1 = convert (result_type, op1);
1116 
1117   arg0 = c_common_get_narrower (op0, &unsigned0);
1118   arg1 = c_common_get_narrower (op1, &unsigned1);
1119 
1120   /* UNS is 1 if the operation to be done is an unsigned one.  */
1121   uns = TYPE_UNSIGNED (result_type);
1122 
1123   /* Handle the case that OP0 (or OP1) does not *contain* a conversion
1124      but it *requires* conversion to FINAL_TYPE.  */
1125 
1126   if ((TYPE_PRECISION (TREE_TYPE (op0))
1127        == TYPE_PRECISION (TREE_TYPE (arg0)))
1128       && TREE_TYPE (op0) != result_type)
1129     unsigned0 = TYPE_UNSIGNED (TREE_TYPE (op0));
1130   if ((TYPE_PRECISION (TREE_TYPE (op1))
1131        == TYPE_PRECISION (TREE_TYPE (arg1)))
1132       && TREE_TYPE (op1) != result_type)
1133     unsigned1 = TYPE_UNSIGNED (TREE_TYPE (op1));
1134 
1135   /* Now UNSIGNED0 is 1 if ARG0 zero-extends to FINAL_TYPE.  */
1136 
1137   /* For bitwise operations, signedness of nominal type
1138      does not matter.  Consider only how operands were extended.  */
1139   if (bitwise)
1140     uns = unsigned0;
1141 
1142   /* Note that in all three cases below we refrain from optimizing
1143      an unsigned operation on sign-extended args.
1144      That would not be valid.  */
1145 
1146   /* Both args variable: if both extended in same way
1147      from same width, do it in that width.
1148      Do it unsigned if args were zero-extended.  */
1149   if ((TYPE_PRECISION (TREE_TYPE (arg0))
1150        < TYPE_PRECISION (result_type))
1151       && (TYPE_PRECISION (TREE_TYPE (arg1))
1152 	  == TYPE_PRECISION (TREE_TYPE (arg0)))
1153       && unsigned0 == unsigned1
1154       && (unsigned0 || !uns))
1155     return c_common_signed_or_unsigned_type
1156       (unsigned0, common_type (TREE_TYPE (arg0), TREE_TYPE (arg1)));
1157 
1158   else if (TREE_CODE (arg0) == INTEGER_CST
1159 	   && (unsigned1 || !uns)
1160 	   && (TYPE_PRECISION (TREE_TYPE (arg1))
1161 	       < TYPE_PRECISION (result_type))
1162 	   && (type
1163 	       = c_common_signed_or_unsigned_type (unsigned1,
1164 						   TREE_TYPE (arg1)))
1165 	   && !POINTER_TYPE_P (type)
1166 	   && int_fits_type_p (arg0, type))
1167     return type;
1168 
1169   else if (TREE_CODE (arg1) == INTEGER_CST
1170 	   && (unsigned0 || !uns)
1171 	   && (TYPE_PRECISION (TREE_TYPE (arg0))
1172 	       < TYPE_PRECISION (result_type))
1173 	   && (type
1174 	       = c_common_signed_or_unsigned_type (unsigned0,
1175 						   TREE_TYPE (arg0)))
1176 	   && !POINTER_TYPE_P (type)
1177 	   && int_fits_type_p (arg1, type))
1178     return type;
1179 
1180   return result_type;
1181 }
1182 
1183 /* Returns true iff any integer value of type FROM_TYPE can be represented as
1184    real of type TO_TYPE.  This is a helper function for unsafe_conversion_p.  */
1185 
1186 static bool
1187 int_safely_convertible_to_real_p (const_tree from_type, const_tree to_type)
1188 {
1189   tree type_low_bound = TYPE_MIN_VALUE (from_type);
1190   tree type_high_bound = TYPE_MAX_VALUE (from_type);
1191   REAL_VALUE_TYPE real_low_bound =
1192 	  real_value_from_int_cst (0, type_low_bound);
1193   REAL_VALUE_TYPE real_high_bound =
1194 	  real_value_from_int_cst (0, type_high_bound);
1195 
1196   return exact_real_truncate (TYPE_MODE (to_type), &real_low_bound)
1197 	 && exact_real_truncate (TYPE_MODE (to_type), &real_high_bound);
1198 }
1199 
1200 /* Checks if expression EXPR of complex/real/integer type cannot be converted
1201    to the complex/real/integer type TYPE.  Function returns non-zero when:
1202 	* EXPR is a constant which cannot be exactly converted to TYPE.
1203 	* EXPR is not a constant and size of EXPR's type > than size of TYPE,
1204 	  for EXPR type and TYPE being both integers or both real, or both
1205 	  complex.
1206 	* EXPR is not a constant of complex type and TYPE is a real or
1207 	  an integer.
1208 	* EXPR is not a constant of real type and TYPE is an integer.
1209 	* EXPR is not a constant of integer type which cannot be
1210 	  exactly converted to real type.
1211 
1212    Function allows conversions between types of different signedness and
1213    can return SAFE_CONVERSION (zero) in that case.  Function can produce
1214    signedness warnings if PRODUCE_WARNS is true.
1215 
1216    RESULT, when non-null is the result of the conversion.  When constant
1217    it is included in the text of diagnostics.
1218 
1219    Function allows conversions from complex constants to non-complex types,
1220    provided that imaginary part is zero and real part can be safely converted
1221    to TYPE.  */
1222 
1223 enum conversion_safety
1224 unsafe_conversion_p (location_t loc, tree type, tree expr, tree result,
1225 		     bool produce_warns)
1226 {
1227   enum conversion_safety give_warning = SAFE_CONVERSION; /* is 0 or false */
1228   tree expr_type = TREE_TYPE (expr);
1229 
1230   bool cstresult = (result
1231 		    && TREE_CODE_CLASS (TREE_CODE (result)) == tcc_constant);
1232 
1233     loc = expansion_point_location_if_in_system_header (loc);
1234 
1235   if (TREE_CODE (expr) == REAL_CST || TREE_CODE (expr) == INTEGER_CST)
1236     {
1237       /* If type is complex, we are interested in compatibility with
1238 	 underlying type.  */
1239       if (TREE_CODE (type) == COMPLEX_TYPE)
1240 	  type = TREE_TYPE (type);
1241 
1242       /* Warn for real constant that is not an exact integer converted
1243 	 to integer type.  */
1244       if (TREE_CODE (expr_type) == REAL_TYPE
1245 	  && TREE_CODE (type) == INTEGER_TYPE)
1246 	{
1247 	  if (!real_isinteger (TREE_REAL_CST_PTR (expr), TYPE_MODE (expr_type)))
1248 	    give_warning = UNSAFE_REAL;
1249 	}
1250       /* Warn for an integer constant that does not fit into integer type.  */
1251       else if (TREE_CODE (expr_type) == INTEGER_TYPE
1252 	       && TREE_CODE (type) == INTEGER_TYPE
1253 	       && !int_fits_type_p (expr, type))
1254 	{
1255 	  if (TYPE_UNSIGNED (type) && !TYPE_UNSIGNED (expr_type)
1256 	      && tree_int_cst_sgn (expr) < 0)
1257 	    {
1258 	      if (produce_warns)
1259 		{
1260 		  if (cstresult)
1261 		    warning_at (loc, OPT_Wsign_conversion,
1262 				"unsigned conversion from %qT to %qT "
1263 				"changes value from %qE to %qE",
1264 				expr_type, type, expr, result);
1265 		  else
1266 		    warning_at (loc, OPT_Wsign_conversion,
1267 				"unsigned conversion from %qT to %qT "
1268 				"changes the value of %qE",
1269 				expr_type, type, expr);
1270 		}
1271 	    }
1272 	  else if (!TYPE_UNSIGNED (type) && TYPE_UNSIGNED (expr_type))
1273 	    {
1274 	      if (cstresult)
1275 		warning_at (loc, OPT_Wsign_conversion,
1276 			    "signed conversion from %qT to %qT changes "
1277 			    "value from %qE to %qE",
1278 			    expr_type, type, expr, result);
1279 	      else
1280 		warning_at (loc, OPT_Wsign_conversion,
1281 			    "signed conversion from %qT to %qT changes "
1282 			    "the value of %qE",
1283 			    expr_type, type, expr);
1284 	    }
1285 	  else
1286 	    give_warning = UNSAFE_OTHER;
1287 	}
1288       else if (TREE_CODE (type) == REAL_TYPE)
1289 	{
1290 	  /* Warn for an integer constant that does not fit into real type.  */
1291 	  if (TREE_CODE (expr_type) == INTEGER_TYPE)
1292 	    {
1293 	      REAL_VALUE_TYPE a = real_value_from_int_cst (0, expr);
1294 	      if (!exact_real_truncate (TYPE_MODE (type), &a))
1295 		give_warning = UNSAFE_REAL;
1296 	    }
1297 	  /* Warn for a real constant that does not fit into a smaller
1298 	     real type.  */
1299 	  else if (TREE_CODE (expr_type) == REAL_TYPE
1300 		   && TYPE_PRECISION (type) < TYPE_PRECISION (expr_type))
1301 	    {
1302 	      REAL_VALUE_TYPE a = TREE_REAL_CST (expr);
1303 	      if (!exact_real_truncate (TYPE_MODE (type), &a))
1304 		give_warning = UNSAFE_REAL;
1305 	    }
1306 	}
1307     }
1308 
1309   else if (TREE_CODE (expr) == COMPLEX_CST)
1310     {
1311       tree imag_part = TREE_IMAGPART (expr);
1312       /* Conversion from complex constant with zero imaginary part,
1313 	 perform check for conversion of real part.  */
1314       if ((TREE_CODE (imag_part) == REAL_CST
1315 	   && real_zerop (imag_part))
1316 	  || (TREE_CODE (imag_part) == INTEGER_CST
1317 	      && integer_zerop (imag_part)))
1318 	/* Note: in this branch we use recursive call to unsafe_conversion_p
1319 	   with different type of EXPR, but it is still safe, because when EXPR
1320 	   is a constant, it's type is not used in text of generated warnings
1321 	   (otherwise they could sound misleading).  */
1322 	return unsafe_conversion_p (loc, type, TREE_REALPART (expr), result,
1323 				    produce_warns);
1324       /* Conversion from complex constant with non-zero imaginary part.  */
1325       else
1326 	{
1327 	  /* Conversion to complex type.
1328 	     Perform checks for both real and imaginary parts.  */
1329 	  if (TREE_CODE (type) == COMPLEX_TYPE)
1330 	    {
1331 	      /* Unfortunately, produce_warns must be false in two subsequent
1332 		 calls of unsafe_conversion_p, because otherwise we could
1333 		 produce strange "double" warnings, if both real and imaginary
1334 		 parts have conversion problems related to signedness.
1335 
1336 		 For example:
1337 		 int32_t _Complex a = 0x80000000 + 0x80000000i;
1338 
1339 		 Possible solution: add a separate function for checking
1340 		 constants and combine result of two calls appropriately.  */
1341 	      enum conversion_safety re_safety =
1342 		  unsafe_conversion_p (loc, type, TREE_REALPART (expr),
1343 				       result, false);
1344 	      enum conversion_safety im_safety =
1345 		unsafe_conversion_p (loc, type, imag_part, result, false);
1346 
1347 	      /* Merge the results into appropriate single warning.  */
1348 
1349 	      /* Note: this case includes SAFE_CONVERSION, i.e. success.  */
1350 	      if (re_safety == im_safety)
1351 		give_warning = re_safety;
1352 	      else if (!re_safety && im_safety)
1353 		give_warning = im_safety;
1354 	      else if (re_safety && !im_safety)
1355 		give_warning = re_safety;
1356 	      else
1357 		give_warning = UNSAFE_OTHER;
1358 	    }
1359 	  /* Warn about conversion from complex to real or integer type.  */
1360 	  else
1361 	    give_warning = UNSAFE_IMAGINARY;
1362 	}
1363     }
1364 
1365   /* Checks for remaining case: EXPR is not constant.  */
1366   else
1367     {
1368       /* Warn for real types converted to integer types.  */
1369       if (TREE_CODE (expr_type) == REAL_TYPE
1370 	  && TREE_CODE (type) == INTEGER_TYPE)
1371 	give_warning = UNSAFE_REAL;
1372 
1373       else if (TREE_CODE (expr_type) == INTEGER_TYPE
1374 	       && TREE_CODE (type) == INTEGER_TYPE)
1375 	{
1376 	  /* Don't warn about unsigned char y = 0xff, x = (int) y;  */
1377 	  expr = get_unwidened (expr, 0);
1378 	  expr_type = TREE_TYPE (expr);
1379 
1380 	  /* Don't warn for short y; short x = ((int)y & 0xff);  */
1381 	  if (TREE_CODE (expr) == BIT_AND_EXPR
1382 	      || TREE_CODE (expr) == BIT_IOR_EXPR
1383 	      || TREE_CODE (expr) == BIT_XOR_EXPR)
1384 	    {
1385 	      /* If both args were extended from a shortest type,
1386 		 use that type if that is safe.  */
1387 	      expr_type = shorten_binary_op (expr_type,
1388 					     TREE_OPERAND (expr, 0),
1389 					     TREE_OPERAND (expr, 1),
1390 					     /* bitwise */1);
1391 
1392 	      if (TREE_CODE (expr) == BIT_AND_EXPR)
1393 		{
1394 		  tree op0 = TREE_OPERAND (expr, 0);
1395 		  tree op1 = TREE_OPERAND (expr, 1);
1396 		  bool unsigned0 = TYPE_UNSIGNED (TREE_TYPE (op0));
1397 		  bool unsigned1 = TYPE_UNSIGNED (TREE_TYPE (op1));
1398 
1399 		  /* If one of the operands is a non-negative constant
1400 		     that fits in the target type, then the type of the
1401 		     other operand does not matter. */
1402 		  if ((TREE_CODE (op0) == INTEGER_CST
1403 		       && int_fits_type_p (op0, c_common_signed_type (type))
1404 		       && int_fits_type_p (op0, c_common_unsigned_type (type)))
1405 		      || (TREE_CODE (op1) == INTEGER_CST
1406 			  && int_fits_type_p (op1, c_common_signed_type (type))
1407 			  && int_fits_type_p (op1,
1408 					      c_common_unsigned_type (type))))
1409 		    return SAFE_CONVERSION;
1410 		  /* If constant is unsigned and fits in the target
1411 		     type, then the result will also fit.  */
1412 		  else if ((TREE_CODE (op0) == INTEGER_CST
1413 			    && unsigned0
1414 			    && int_fits_type_p (op0, type))
1415 			   || (TREE_CODE (op1) == INTEGER_CST
1416 			       && unsigned1
1417 			       && int_fits_type_p (op1, type)))
1418 		    return SAFE_CONVERSION;
1419 		}
1420 	    }
1421 	  /* Warn for integer types converted to smaller integer types.  */
1422 	  if (TYPE_PRECISION (type) < TYPE_PRECISION (expr_type))
1423 	    give_warning = UNSAFE_OTHER;
1424 
1425 	  /* When they are the same width but different signedness,
1426 	     then the value may change.  */
1427 	  else if (((TYPE_PRECISION (type) == TYPE_PRECISION (expr_type)
1428 		    && TYPE_UNSIGNED (expr_type) != TYPE_UNSIGNED (type))
1429 		   /* Even when converted to a bigger type, if the type is
1430 		      unsigned but expr is signed, then negative values
1431 		      will be changed.  */
1432 		    || (TYPE_UNSIGNED (type) && !TYPE_UNSIGNED (expr_type)))
1433 		   && produce_warns)
1434 	    warning_at (loc, OPT_Wsign_conversion, "conversion to %qT from %qT "
1435 			"may change the sign of the result",
1436 			type, expr_type);
1437 	}
1438 
1439       /* Warn for integer types converted to real types if and only if
1440 	 all the range of values of the integer type cannot be
1441 	 represented by the real type.  */
1442       else if (TREE_CODE (expr_type) == INTEGER_TYPE
1443 	       && TREE_CODE (type) == REAL_TYPE)
1444 	{
1445 	  /* Don't warn about char y = 0xff; float x = (int) y;  */
1446 	  expr = get_unwidened (expr, 0);
1447 	  expr_type = TREE_TYPE (expr);
1448 
1449 	  if (!int_safely_convertible_to_real_p (expr_type, type))
1450 	    give_warning = UNSAFE_OTHER;
1451 	}
1452 
1453       /* Warn for real types converted to smaller real types.  */
1454       else if (TREE_CODE (expr_type) == REAL_TYPE
1455 	       && TREE_CODE (type) == REAL_TYPE
1456 	       && TYPE_PRECISION (type) < TYPE_PRECISION (expr_type))
1457 	give_warning = UNSAFE_REAL;
1458 
1459       /* Check conversion between two complex types.  */
1460       else if (TREE_CODE (expr_type) == COMPLEX_TYPE
1461 	       && TREE_CODE (type) == COMPLEX_TYPE)
1462 	{
1463 	  /* Extract underlying types (i.e., type of real and imaginary
1464 	     parts) of expr_type and type.  */
1465 	  tree from_type = TREE_TYPE (expr_type);
1466 	  tree to_type = TREE_TYPE (type);
1467 
1468 	  /* Warn for real types converted to integer types.  */
1469 	  if (TREE_CODE (from_type) == REAL_TYPE
1470 	      && TREE_CODE (to_type) == INTEGER_TYPE)
1471 	    give_warning = UNSAFE_REAL;
1472 
1473 	  /* Warn for real types converted to smaller real types.  */
1474 	  else if (TREE_CODE (from_type) == REAL_TYPE
1475 		   && TREE_CODE (to_type) == REAL_TYPE
1476 		   && TYPE_PRECISION (to_type) < TYPE_PRECISION (from_type))
1477 	    give_warning = UNSAFE_REAL;
1478 
1479 	  /* Check conversion for complex integer types.  Here implementation
1480 	     is simpler than for real-domain integers because it does not
1481 	     involve sophisticated cases, such as bitmasks, casts, etc.  */
1482 	  else if (TREE_CODE (from_type) == INTEGER_TYPE
1483 		   && TREE_CODE (to_type) == INTEGER_TYPE)
1484 	    {
1485 	      /* Warn for integer types converted to smaller integer types.  */
1486 	      if (TYPE_PRECISION (to_type) < TYPE_PRECISION (from_type))
1487 		give_warning = UNSAFE_OTHER;
1488 
1489 	      /* Check for different signedness, see case for real-domain
1490 		 integers (above) for a more detailed comment.  */
1491 	      else if (((TYPE_PRECISION (to_type) == TYPE_PRECISION (from_type)
1492 		    && TYPE_UNSIGNED (to_type) != TYPE_UNSIGNED (from_type))
1493 		    || (TYPE_UNSIGNED (to_type) && !TYPE_UNSIGNED (from_type)))
1494 		    && produce_warns)
1495 		warning_at (loc, OPT_Wsign_conversion,
1496 			"conversion to %qT from %qT "
1497 			"may change the sign of the result",
1498 			type, expr_type);
1499 	    }
1500 	  else if (TREE_CODE (from_type) == INTEGER_TYPE
1501 		   && TREE_CODE (to_type) == REAL_TYPE
1502 		   && !int_safely_convertible_to_real_p (from_type, to_type))
1503 	    give_warning = UNSAFE_OTHER;
1504 	}
1505 
1506       /* Warn for complex types converted to real or integer types.  */
1507       else if (TREE_CODE (expr_type) == COMPLEX_TYPE
1508 	       && TREE_CODE (type) != COMPLEX_TYPE)
1509 	give_warning = UNSAFE_IMAGINARY;
1510     }
1511 
1512   return give_warning;
1513 }
1514 
1515 
1516 /* Convert EXPR to TYPE, warning about conversion problems with constants.
1517    Invoke this function on every expression that is converted implicitly,
1518    i.e. because of language rules and not because of an explicit cast.  */
1519 
1520 tree
1521 convert_and_check (location_t loc, tree type, tree expr)
1522 {
1523   tree result;
1524   tree expr_for_warning;
1525 
1526   /* Convert from a value with possible excess precision rather than
1527      via the semantic type, but do not warn about values not fitting
1528      exactly in the semantic type.  */
1529   if (TREE_CODE (expr) == EXCESS_PRECISION_EXPR)
1530     {
1531       tree orig_type = TREE_TYPE (expr);
1532       expr = TREE_OPERAND (expr, 0);
1533       expr_for_warning = convert (orig_type, expr);
1534       if (orig_type == type)
1535 	return expr_for_warning;
1536     }
1537   else
1538     expr_for_warning = expr;
1539 
1540   if (TREE_TYPE (expr) == type)
1541     return expr;
1542 
1543   result = convert (type, expr);
1544 
1545   if (c_inhibit_evaluation_warnings == 0
1546       && !TREE_OVERFLOW_P (expr)
1547       && result != error_mark_node)
1548     warnings_for_convert_and_check (loc, type, expr_for_warning, result);
1549 
1550   return result;
1551 }
1552 
1553 /* A node in a list that describes references to variables (EXPR), which are
1554    either read accesses if WRITER is zero, or write accesses, in which case
1555    WRITER is the parent of EXPR.  */
1556 struct tlist
1557 {
1558   struct tlist *next;
1559   tree expr, writer;
1560 };
1561 
1562 /* Used to implement a cache the results of a call to verify_tree.  We only
1563    use this for SAVE_EXPRs.  */
1564 struct tlist_cache
1565 {
1566   struct tlist_cache *next;
1567   struct tlist *cache_before_sp;
1568   struct tlist *cache_after_sp;
1569   tree expr;
1570 };
1571 
1572 /* Obstack to use when allocating tlist structures, and corresponding
1573    firstobj.  */
1574 static struct obstack tlist_obstack;
1575 static char *tlist_firstobj = 0;
1576 
1577 /* Keep track of the identifiers we've warned about, so we can avoid duplicate
1578    warnings.  */
1579 static struct tlist *warned_ids;
1580 /* SAVE_EXPRs need special treatment.  We process them only once and then
1581    cache the results.  */
1582 static struct tlist_cache *save_expr_cache;
1583 
1584 static void add_tlist (struct tlist **, struct tlist *, tree, int);
1585 static void merge_tlist (struct tlist **, struct tlist *, int);
1586 static void verify_tree (tree, struct tlist **, struct tlist **, tree);
1587 static bool warning_candidate_p (tree);
1588 static bool candidate_equal_p (const_tree, const_tree);
1589 static void warn_for_collisions (struct tlist *);
1590 static void warn_for_collisions_1 (tree, tree, struct tlist *, int);
1591 static struct tlist *new_tlist (struct tlist *, tree, tree);
1592 
1593 /* Create a new struct tlist and fill in its fields.  */
1594 static struct tlist *
1595 new_tlist (struct tlist *next, tree t, tree writer)
1596 {
1597   struct tlist *l;
1598   l = XOBNEW (&tlist_obstack, struct tlist);
1599   l->next = next;
1600   l->expr = t;
1601   l->writer = writer;
1602   return l;
1603 }
1604 
1605 /* Add duplicates of the nodes found in ADD to the list *TO.  If EXCLUDE_WRITER
1606    is nonnull, we ignore any node we find which has a writer equal to it.  */
1607 
1608 static void
1609 add_tlist (struct tlist **to, struct tlist *add, tree exclude_writer, int copy)
1610 {
1611   while (add)
1612     {
1613       struct tlist *next = add->next;
1614       if (!copy)
1615 	add->next = *to;
1616       if (!exclude_writer || !candidate_equal_p (add->writer, exclude_writer))
1617 	*to = copy ? new_tlist (*to, add->expr, add->writer) : add;
1618       add = next;
1619     }
1620 }
1621 
1622 /* Merge the nodes of ADD into TO.  This merging process is done so that for
1623    each variable that already exists in TO, no new node is added; however if
1624    there is a write access recorded in ADD, and an occurrence on TO is only
1625    a read access, then the occurrence in TO will be modified to record the
1626    write.  */
1627 
1628 static void
1629 merge_tlist (struct tlist **to, struct tlist *add, int copy)
1630 {
1631   struct tlist **end = to;
1632 
1633   while (*end)
1634     end = &(*end)->next;
1635 
1636   while (add)
1637     {
1638       int found = 0;
1639       struct tlist *tmp2;
1640       struct tlist *next = add->next;
1641 
1642       for (tmp2 = *to; tmp2; tmp2 = tmp2->next)
1643 	if (candidate_equal_p (tmp2->expr, add->expr))
1644 	  {
1645 	    found = 1;
1646 	    if (!tmp2->writer)
1647 	      tmp2->writer = add->writer;
1648 	  }
1649       if (!found)
1650 	{
1651 	  *end = copy ? new_tlist (NULL, add->expr, add->writer) : add;
1652 	  end = &(*end)->next;
1653 	  *end = 0;
1654 	}
1655       add = next;
1656     }
1657 }
1658 
1659 /* WRITTEN is a variable, WRITER is its parent.  Warn if any of the variable
1660    references in list LIST conflict with it, excluding reads if ONLY writers
1661    is nonzero.  */
1662 
1663 static void
1664 warn_for_collisions_1 (tree written, tree writer, struct tlist *list,
1665 		       int only_writes)
1666 {
1667   struct tlist *tmp;
1668 
1669   /* Avoid duplicate warnings.  */
1670   for (tmp = warned_ids; tmp; tmp = tmp->next)
1671     if (candidate_equal_p (tmp->expr, written))
1672       return;
1673 
1674   while (list)
1675     {
1676       if (candidate_equal_p (list->expr, written)
1677 	  && !candidate_equal_p (list->writer, writer)
1678 	  && (!only_writes || list->writer))
1679 	{
1680 	  warned_ids = new_tlist (warned_ids, written, NULL_TREE);
1681 	  warning_at (EXPR_LOC_OR_LOC (writer, input_location),
1682 		      OPT_Wsequence_point, "operation on %qE may be undefined",
1683 		      list->expr);
1684 	}
1685       list = list->next;
1686     }
1687 }
1688 
1689 /* Given a list LIST of references to variables, find whether any of these
1690    can cause conflicts due to missing sequence points.  */
1691 
1692 static void
1693 warn_for_collisions (struct tlist *list)
1694 {
1695   struct tlist *tmp;
1696 
1697   for (tmp = list; tmp; tmp = tmp->next)
1698     {
1699       if (tmp->writer)
1700 	warn_for_collisions_1 (tmp->expr, tmp->writer, list, 0);
1701     }
1702 }
1703 
1704 /* Return nonzero if X is a tree that can be verified by the sequence point
1705    warnings.  */
1706 
1707 static bool
1708 warning_candidate_p (tree x)
1709 {
1710   if (DECL_P (x) && DECL_ARTIFICIAL (x))
1711     return false;
1712 
1713   if (TREE_CODE (x) == BLOCK)
1714     return false;
1715 
1716   /* VOID_TYPE_P (TREE_TYPE (x)) is workaround for cp/tree.c
1717      (lvalue_p) crash on TRY/CATCH. */
1718   if (TREE_TYPE (x) == NULL_TREE || VOID_TYPE_P (TREE_TYPE (x)))
1719     return false;
1720 
1721   if (!lvalue_p (x))
1722     return false;
1723 
1724   /* No point to track non-const calls, they will never satisfy
1725      operand_equal_p.  */
1726   if (TREE_CODE (x) == CALL_EXPR && (call_expr_flags (x) & ECF_CONST) == 0)
1727     return false;
1728 
1729   if (TREE_CODE (x) == STRING_CST)
1730     return false;
1731 
1732   return true;
1733 }
1734 
1735 /* Return nonzero if X and Y appear to be the same candidate (or NULL) */
1736 static bool
1737 candidate_equal_p (const_tree x, const_tree y)
1738 {
1739   return (x == y) || (x && y && operand_equal_p (x, y, 0));
1740 }
1741 
1742 /* Walk the tree X, and record accesses to variables.  If X is written by the
1743    parent tree, WRITER is the parent.
1744    We store accesses in one of the two lists: PBEFORE_SP, and PNO_SP.  If this
1745    expression or its only operand forces a sequence point, then everything up
1746    to the sequence point is stored in PBEFORE_SP.  Everything else gets stored
1747    in PNO_SP.
1748    Once we return, we will have emitted warnings if any subexpression before
1749    such a sequence point could be undefined.  On a higher level, however, the
1750    sequence point may not be relevant, and we'll merge the two lists.
1751 
1752    Example: (b++, a) + b;
1753    The call that processes the COMPOUND_EXPR will store the increment of B
1754    in PBEFORE_SP, and the use of A in PNO_SP.  The higher-level call that
1755    processes the PLUS_EXPR will need to merge the two lists so that
1756    eventually, all accesses end up on the same list (and we'll warn about the
1757    unordered subexpressions b++ and b.
1758 
1759    A note on merging.  If we modify the former example so that our expression
1760    becomes
1761      (b++, b) + a
1762    care must be taken not simply to add all three expressions into the final
1763    PNO_SP list.  The function merge_tlist takes care of that by merging the
1764    before-SP list of the COMPOUND_EXPR into its after-SP list in a special
1765    way, so that no more than one access to B is recorded.  */
1766 
1767 static void
1768 verify_tree (tree x, struct tlist **pbefore_sp, struct tlist **pno_sp,
1769 	     tree writer)
1770 {
1771   struct tlist *tmp_before, *tmp_nosp, *tmp_list2, *tmp_list3;
1772   enum tree_code code;
1773   enum tree_code_class cl;
1774 
1775   /* X may be NULL if it is the operand of an empty statement expression
1776      ({ }).  */
1777   if (x == NULL)
1778     return;
1779 
1780  restart:
1781   code = TREE_CODE (x);
1782   cl = TREE_CODE_CLASS (code);
1783 
1784   if (warning_candidate_p (x))
1785     *pno_sp = new_tlist (*pno_sp, x, writer);
1786 
1787   switch (code)
1788     {
1789     case CONSTRUCTOR:
1790     case SIZEOF_EXPR:
1791       return;
1792 
1793     case COMPOUND_EXPR:
1794     case TRUTH_ANDIF_EXPR:
1795     case TRUTH_ORIF_EXPR:
1796       tmp_before = tmp_nosp = tmp_list2 = tmp_list3 = 0;
1797       verify_tree (TREE_OPERAND (x, 0), &tmp_before, &tmp_nosp, NULL_TREE);
1798       warn_for_collisions (tmp_nosp);
1799       merge_tlist (pbefore_sp, tmp_before, 0);
1800       merge_tlist (pbefore_sp, tmp_nosp, 0);
1801       verify_tree (TREE_OPERAND (x, 1), &tmp_list3, &tmp_list2, NULL_TREE);
1802       warn_for_collisions (tmp_list2);
1803       merge_tlist (pbefore_sp, tmp_list3, 0);
1804       merge_tlist (pno_sp, tmp_list2, 0);
1805       return;
1806 
1807     case COND_EXPR:
1808       tmp_before = tmp_list2 = 0;
1809       verify_tree (TREE_OPERAND (x, 0), &tmp_before, &tmp_list2, NULL_TREE);
1810       warn_for_collisions (tmp_list2);
1811       merge_tlist (pbefore_sp, tmp_before, 0);
1812       merge_tlist (pbefore_sp, tmp_list2, 0);
1813 
1814       tmp_list3 = tmp_nosp = 0;
1815       verify_tree (TREE_OPERAND (x, 1), &tmp_list3, &tmp_nosp, NULL_TREE);
1816       warn_for_collisions (tmp_nosp);
1817       merge_tlist (pbefore_sp, tmp_list3, 0);
1818 
1819       tmp_list3 = tmp_list2 = 0;
1820       verify_tree (TREE_OPERAND (x, 2), &tmp_list3, &tmp_list2, NULL_TREE);
1821       warn_for_collisions (tmp_list2);
1822       merge_tlist (pbefore_sp, tmp_list3, 0);
1823       /* Rather than add both tmp_nosp and tmp_list2, we have to merge the
1824 	 two first, to avoid warning for (a ? b++ : b++).  */
1825       merge_tlist (&tmp_nosp, tmp_list2, 0);
1826       add_tlist (pno_sp, tmp_nosp, NULL_TREE, 0);
1827       return;
1828 
1829     case PREDECREMENT_EXPR:
1830     case PREINCREMENT_EXPR:
1831     case POSTDECREMENT_EXPR:
1832     case POSTINCREMENT_EXPR:
1833       verify_tree (TREE_OPERAND (x, 0), pno_sp, pno_sp, x);
1834       return;
1835 
1836     case MODIFY_EXPR:
1837       tmp_before = tmp_nosp = tmp_list3 = 0;
1838       verify_tree (TREE_OPERAND (x, 1), &tmp_before, &tmp_nosp, NULL_TREE);
1839       verify_tree (TREE_OPERAND (x, 0), &tmp_list3, &tmp_list3, x);
1840       /* Expressions inside the LHS are not ordered wrt. the sequence points
1841 	 in the RHS.  Example:
1842 	   *a = (a++, 2)
1843 	 Despite the fact that the modification of "a" is in the before_sp
1844 	 list (tmp_before), it conflicts with the use of "a" in the LHS.
1845 	 We can handle this by adding the contents of tmp_list3
1846 	 to those of tmp_before, and redoing the collision warnings for that
1847 	 list.  */
1848       add_tlist (&tmp_before, tmp_list3, x, 1);
1849       warn_for_collisions (tmp_before);
1850       /* Exclude the LHS itself here; we first have to merge it into the
1851 	 tmp_nosp list.  This is done to avoid warning for "a = a"; if we
1852 	 didn't exclude the LHS, we'd get it twice, once as a read and once
1853 	 as a write.  */
1854       add_tlist (pno_sp, tmp_list3, x, 0);
1855       warn_for_collisions_1 (TREE_OPERAND (x, 0), x, tmp_nosp, 1);
1856 
1857       merge_tlist (pbefore_sp, tmp_before, 0);
1858       if (warning_candidate_p (TREE_OPERAND (x, 0)))
1859 	merge_tlist (&tmp_nosp, new_tlist (NULL, TREE_OPERAND (x, 0), x), 0);
1860       add_tlist (pno_sp, tmp_nosp, NULL_TREE, 1);
1861       return;
1862 
1863     case CALL_EXPR:
1864       /* We need to warn about conflicts among arguments and conflicts between
1865 	 args and the function address.  Side effects of the function address,
1866 	 however, are not ordered by the sequence point of the call.  */
1867       {
1868 	call_expr_arg_iterator iter;
1869 	tree arg;
1870 	tmp_before = tmp_nosp = 0;
1871 	verify_tree (CALL_EXPR_FN (x), &tmp_before, &tmp_nosp, NULL_TREE);
1872 	FOR_EACH_CALL_EXPR_ARG (arg, iter, x)
1873 	  {
1874 	    tmp_list2 = tmp_list3 = 0;
1875 	    verify_tree (arg, &tmp_list2, &tmp_list3, NULL_TREE);
1876 	    merge_tlist (&tmp_list3, tmp_list2, 0);
1877 	    add_tlist (&tmp_before, tmp_list3, NULL_TREE, 0);
1878 	  }
1879 	add_tlist (&tmp_before, tmp_nosp, NULL_TREE, 0);
1880 	warn_for_collisions (tmp_before);
1881 	add_tlist (pbefore_sp, tmp_before, NULL_TREE, 0);
1882 	return;
1883       }
1884 
1885     case TREE_LIST:
1886       /* Scan all the list, e.g. indices of multi dimensional array.  */
1887       while (x)
1888 	{
1889 	  tmp_before = tmp_nosp = 0;
1890 	  verify_tree (TREE_VALUE (x), &tmp_before, &tmp_nosp, NULL_TREE);
1891 	  merge_tlist (&tmp_nosp, tmp_before, 0);
1892 	  add_tlist (pno_sp, tmp_nosp, NULL_TREE, 0);
1893 	  x = TREE_CHAIN (x);
1894 	}
1895       return;
1896 
1897     case SAVE_EXPR:
1898       {
1899 	struct tlist_cache *t;
1900 	for (t = save_expr_cache; t; t = t->next)
1901 	  if (candidate_equal_p (t->expr, x))
1902 	    break;
1903 
1904 	if (!t)
1905 	  {
1906 	    t = XOBNEW (&tlist_obstack, struct tlist_cache);
1907 	    t->next = save_expr_cache;
1908 	    t->expr = x;
1909 	    save_expr_cache = t;
1910 
1911 	    tmp_before = tmp_nosp = 0;
1912 	    verify_tree (TREE_OPERAND (x, 0), &tmp_before, &tmp_nosp, NULL_TREE);
1913 	    warn_for_collisions (tmp_nosp);
1914 
1915 	    tmp_list3 = 0;
1916 	    merge_tlist (&tmp_list3, tmp_nosp, 0);
1917 	    t->cache_before_sp = tmp_before;
1918 	    t->cache_after_sp = tmp_list3;
1919 	  }
1920 	merge_tlist (pbefore_sp, t->cache_before_sp, 1);
1921 	add_tlist (pno_sp, t->cache_after_sp, NULL_TREE, 1);
1922 	return;
1923       }
1924 
1925     case ADDR_EXPR:
1926       x = TREE_OPERAND (x, 0);
1927       if (DECL_P (x))
1928 	return;
1929       writer = 0;
1930       goto restart;
1931 
1932     default:
1933       /* For other expressions, simply recurse on their operands.
1934 	 Manual tail recursion for unary expressions.
1935 	 Other non-expressions need not be processed.  */
1936       if (cl == tcc_unary)
1937 	{
1938 	  x = TREE_OPERAND (x, 0);
1939 	  writer = 0;
1940 	  goto restart;
1941 	}
1942       else if (IS_EXPR_CODE_CLASS (cl))
1943 	{
1944 	  int lp;
1945 	  int max = TREE_OPERAND_LENGTH (x);
1946 	  for (lp = 0; lp < max; lp++)
1947 	    {
1948 	      tmp_before = tmp_nosp = 0;
1949 	      verify_tree (TREE_OPERAND (x, lp), &tmp_before, &tmp_nosp, 0);
1950 	      merge_tlist (&tmp_nosp, tmp_before, 0);
1951 	      add_tlist (pno_sp, tmp_nosp, NULL_TREE, 0);
1952 	    }
1953 	}
1954       return;
1955     }
1956 }
1957 
1958 /* Try to warn for undefined behavior in EXPR due to missing sequence
1959    points.  */
1960 
1961 DEBUG_FUNCTION void
1962 verify_sequence_points (tree expr)
1963 {
1964   struct tlist *before_sp = 0, *after_sp = 0;
1965 
1966   warned_ids = 0;
1967   save_expr_cache = 0;
1968   if (tlist_firstobj == 0)
1969     {
1970       gcc_obstack_init (&tlist_obstack);
1971       tlist_firstobj = (char *) obstack_alloc (&tlist_obstack, 0);
1972     }
1973 
1974   verify_tree (expr, &before_sp, &after_sp, 0);
1975   warn_for_collisions (after_sp);
1976   obstack_free (&tlist_obstack, tlist_firstobj);
1977 }
1978 
1979 /* Validate the expression after `case' and apply default promotions.  */
1980 
1981 static tree
1982 check_case_value (location_t loc, tree value)
1983 {
1984   if (value == NULL_TREE)
1985     return value;
1986 
1987   if (TREE_CODE (value) == INTEGER_CST)
1988     /* Promote char or short to int.  */
1989     value = perform_integral_promotions (value);
1990   else if (value != error_mark_node)
1991     {
1992       error_at (loc, "case label does not reduce to an integer constant");
1993       value = error_mark_node;
1994     }
1995 
1996   constant_expression_warning (value);
1997 
1998   return value;
1999 }
2000 
2001 /* See if the case values LOW and HIGH are in the range of the original
2002    type (i.e. before the default conversion to int) of the switch testing
2003    expression.
2004    TYPE is the promoted type of the testing expression, and ORIG_TYPE is
2005    the type before promoting it.  CASE_LOW_P is a pointer to the lower
2006    bound of the case label, and CASE_HIGH_P is the upper bound or NULL
2007    if the case is not a case range.
2008    The caller has to make sure that we are not called with NULL for
2009    CASE_LOW_P (i.e. the default case).  OUTSIDE_RANGE_P says whether there
2010    was a case value that doesn't fit into the range of the ORIG_TYPE.
2011    Returns true if the case label is in range of ORIG_TYPE (saturated or
2012    untouched) or false if the label is out of range.  */
2013 
2014 static bool
2015 check_case_bounds (location_t loc, tree type, tree orig_type,
2016 		   tree *case_low_p, tree *case_high_p,
2017 		   bool *outside_range_p)
2018 {
2019   tree min_value, max_value;
2020   tree case_low = *case_low_p;
2021   tree case_high = case_high_p ? *case_high_p : case_low;
2022 
2023   /* If there was a problem with the original type, do nothing.  */
2024   if (orig_type == error_mark_node)
2025     return true;
2026 
2027   min_value = TYPE_MIN_VALUE (orig_type);
2028   max_value = TYPE_MAX_VALUE (orig_type);
2029 
2030   /* We'll really need integer constants here.  */
2031   case_low = fold (case_low);
2032   case_high = fold (case_high);
2033 
2034   /* Case label is less than minimum for type.  */
2035   if (tree_int_cst_compare (case_low, min_value) < 0
2036       && tree_int_cst_compare (case_high, min_value) < 0)
2037     {
2038       warning_at (loc, 0, "case label value is less than minimum value "
2039 		  "for type");
2040       *outside_range_p = true;
2041       return false;
2042     }
2043 
2044   /* Case value is greater than maximum for type.  */
2045   if (tree_int_cst_compare (case_low, max_value) > 0
2046       && tree_int_cst_compare (case_high, max_value) > 0)
2047     {
2048       warning_at (loc, 0, "case label value exceeds maximum value for type");
2049       *outside_range_p = true;
2050       return false;
2051     }
2052 
2053   /* Saturate lower case label value to minimum.  */
2054   if (tree_int_cst_compare (case_high, min_value) >= 0
2055       && tree_int_cst_compare (case_low, min_value) < 0)
2056     {
2057       warning_at (loc, 0, "lower value in case label range"
2058 		  " less than minimum value for type");
2059       *outside_range_p = true;
2060       case_low = min_value;
2061     }
2062 
2063   /* Saturate upper case label value to maximum.  */
2064   if (tree_int_cst_compare (case_low, max_value) <= 0
2065       && tree_int_cst_compare (case_high, max_value) > 0)
2066     {
2067       warning_at (loc, 0, "upper value in case label range"
2068 		  " exceeds maximum value for type");
2069       *outside_range_p = true;
2070       case_high = max_value;
2071     }
2072 
2073   if (*case_low_p != case_low)
2074     *case_low_p = convert (type, case_low);
2075   if (case_high_p && *case_high_p != case_high)
2076     *case_high_p = convert (type, case_high);
2077 
2078   return true;
2079 }
2080 
2081 /* Return an integer type with BITS bits of precision,
2082    that is unsigned if UNSIGNEDP is nonzero, otherwise signed.  */
2083 
2084 tree
2085 c_common_type_for_size (unsigned int bits, int unsignedp)
2086 {
2087   int i;
2088 
2089   if (bits == TYPE_PRECISION (integer_type_node))
2090     return unsignedp ? unsigned_type_node : integer_type_node;
2091 
2092   if (bits == TYPE_PRECISION (signed_char_type_node))
2093     return unsignedp ? unsigned_char_type_node : signed_char_type_node;
2094 
2095   if (bits == TYPE_PRECISION (short_integer_type_node))
2096     return unsignedp ? short_unsigned_type_node : short_integer_type_node;
2097 
2098   if (bits == TYPE_PRECISION (long_integer_type_node))
2099     return unsignedp ? long_unsigned_type_node : long_integer_type_node;
2100 
2101   if (bits == TYPE_PRECISION (long_long_integer_type_node))
2102     return (unsignedp ? long_long_unsigned_type_node
2103 	    : long_long_integer_type_node);
2104 
2105   for (i = 0; i < NUM_INT_N_ENTS; i ++)
2106     if (int_n_enabled_p[i]
2107 	&& bits == int_n_data[i].bitsize)
2108       return (unsignedp ? int_n_trees[i].unsigned_type
2109 	      : int_n_trees[i].signed_type);
2110 
2111   if (bits == TYPE_PRECISION (widest_integer_literal_type_node))
2112     return (unsignedp ? widest_unsigned_literal_type_node
2113 	    : widest_integer_literal_type_node);
2114 
2115   if (bits <= TYPE_PRECISION (intQI_type_node))
2116     return unsignedp ? unsigned_intQI_type_node : intQI_type_node;
2117 
2118   if (bits <= TYPE_PRECISION (intHI_type_node))
2119     return unsignedp ? unsigned_intHI_type_node : intHI_type_node;
2120 
2121   if (bits <= TYPE_PRECISION (intSI_type_node))
2122     return unsignedp ? unsigned_intSI_type_node : intSI_type_node;
2123 
2124   if (bits <= TYPE_PRECISION (intDI_type_node))
2125     return unsignedp ? unsigned_intDI_type_node : intDI_type_node;
2126 
2127   return NULL_TREE;
2128 }
2129 
2130 /* Return a fixed-point type that has at least IBIT ibits and FBIT fbits
2131    that is unsigned if UNSIGNEDP is nonzero, otherwise signed;
2132    and saturating if SATP is nonzero, otherwise not saturating.  */
2133 
2134 tree
2135 c_common_fixed_point_type_for_size (unsigned int ibit, unsigned int fbit,
2136 				    int unsignedp, int satp)
2137 {
2138   enum mode_class mclass;
2139   if (ibit == 0)
2140     mclass = unsignedp ? MODE_UFRACT : MODE_FRACT;
2141   else
2142     mclass = unsignedp ? MODE_UACCUM : MODE_ACCUM;
2143 
2144   opt_scalar_mode opt_mode;
2145   scalar_mode mode;
2146   FOR_EACH_MODE_IN_CLASS (opt_mode, mclass)
2147     {
2148       mode = opt_mode.require ();
2149       if (GET_MODE_IBIT (mode) >= ibit && GET_MODE_FBIT (mode) >= fbit)
2150 	break;
2151     }
2152 
2153   if (!opt_mode.exists (&mode) || !targetm.scalar_mode_supported_p (mode))
2154     {
2155       sorry ("GCC cannot support operators with integer types and "
2156 	     "fixed-point types that have too many integral and "
2157 	     "fractional bits together");
2158       return NULL_TREE;
2159     }
2160 
2161   return c_common_type_for_mode (mode, satp);
2162 }
2163 
2164 /* Used for communication between c_common_type_for_mode and
2165    c_register_builtin_type.  */
2166 tree registered_builtin_types;
2167 
2168 /* Return a data type that has machine mode MODE.
2169    If the mode is an integer,
2170    then UNSIGNEDP selects between signed and unsigned types.
2171    If the mode is a fixed-point mode,
2172    then UNSIGNEDP selects between saturating and nonsaturating types.  */
2173 
2174 tree
2175 c_common_type_for_mode (machine_mode mode, int unsignedp)
2176 {
2177   tree t;
2178   int i;
2179 
2180   if (mode == TYPE_MODE (integer_type_node))
2181     return unsignedp ? unsigned_type_node : integer_type_node;
2182 
2183   if (mode == TYPE_MODE (signed_char_type_node))
2184     return unsignedp ? unsigned_char_type_node : signed_char_type_node;
2185 
2186   if (mode == TYPE_MODE (short_integer_type_node))
2187     return unsignedp ? short_unsigned_type_node : short_integer_type_node;
2188 
2189   if (mode == TYPE_MODE (long_integer_type_node))
2190     return unsignedp ? long_unsigned_type_node : long_integer_type_node;
2191 
2192   if (mode == TYPE_MODE (long_long_integer_type_node))
2193     return unsignedp ? long_long_unsigned_type_node : long_long_integer_type_node;
2194 
2195   for (i = 0; i < NUM_INT_N_ENTS; i ++)
2196     if (int_n_enabled_p[i]
2197 	&& mode == int_n_data[i].m)
2198       return (unsignedp ? int_n_trees[i].unsigned_type
2199 	      : int_n_trees[i].signed_type);
2200 
2201   if (mode == QImode)
2202     return unsignedp ? unsigned_intQI_type_node : intQI_type_node;
2203 
2204   if (mode == HImode)
2205     return unsignedp ? unsigned_intHI_type_node : intHI_type_node;
2206 
2207   if (mode == SImode)
2208     return unsignedp ? unsigned_intSI_type_node : intSI_type_node;
2209 
2210   if (mode == DImode)
2211     return unsignedp ? unsigned_intDI_type_node : intDI_type_node;
2212 
2213 #if HOST_BITS_PER_WIDE_INT >= 64
2214   if (mode == TYPE_MODE (intTI_type_node))
2215     return unsignedp ? unsigned_intTI_type_node : intTI_type_node;
2216 #endif
2217 
2218   if (mode == TYPE_MODE (float_type_node))
2219     return float_type_node;
2220 
2221   if (mode == TYPE_MODE (double_type_node))
2222     return double_type_node;
2223 
2224   if (mode == TYPE_MODE (long_double_type_node))
2225     return long_double_type_node;
2226 
2227   for (i = 0; i < NUM_FLOATN_NX_TYPES; i++)
2228     if (FLOATN_NX_TYPE_NODE (i) != NULL_TREE
2229 	&& mode == TYPE_MODE (FLOATN_NX_TYPE_NODE (i)))
2230       return FLOATN_NX_TYPE_NODE (i);
2231 
2232   if (mode == TYPE_MODE (void_type_node))
2233     return void_type_node;
2234 
2235   if (mode == TYPE_MODE (build_pointer_type (char_type_node))
2236       || mode == TYPE_MODE (build_pointer_type (integer_type_node)))
2237     {
2238       unsigned int precision
2239 	= GET_MODE_PRECISION (as_a <scalar_int_mode> (mode));
2240       return (unsignedp
2241 	      ? make_unsigned_type (precision)
2242 	      : make_signed_type (precision));
2243     }
2244 
2245   if (COMPLEX_MODE_P (mode))
2246     {
2247       machine_mode inner_mode;
2248       tree inner_type;
2249 
2250       if (mode == TYPE_MODE (complex_float_type_node))
2251 	return complex_float_type_node;
2252       if (mode == TYPE_MODE (complex_double_type_node))
2253 	return complex_double_type_node;
2254       if (mode == TYPE_MODE (complex_long_double_type_node))
2255 	return complex_long_double_type_node;
2256 
2257       for (i = 0; i < NUM_FLOATN_NX_TYPES; i++)
2258 	if (COMPLEX_FLOATN_NX_TYPE_NODE (i) != NULL_TREE
2259 	    && mode == TYPE_MODE (COMPLEX_FLOATN_NX_TYPE_NODE (i)))
2260 	  return COMPLEX_FLOATN_NX_TYPE_NODE (i);
2261 
2262       if (mode == TYPE_MODE (complex_integer_type_node) && !unsignedp)
2263 	return complex_integer_type_node;
2264 
2265       inner_mode = GET_MODE_INNER (mode);
2266       inner_type = c_common_type_for_mode (inner_mode, unsignedp);
2267       if (inner_type != NULL_TREE)
2268 	return build_complex_type (inner_type);
2269     }
2270   else if (GET_MODE_CLASS (mode) == MODE_VECTOR_BOOL
2271 	   && valid_vector_subparts_p (GET_MODE_NUNITS (mode)))
2272     {
2273       unsigned int elem_bits = vector_element_size (GET_MODE_BITSIZE (mode),
2274 						    GET_MODE_NUNITS (mode));
2275       tree bool_type = build_nonstandard_boolean_type (elem_bits);
2276       return build_vector_type_for_mode (bool_type, mode);
2277     }
2278   else if (VECTOR_MODE_P (mode)
2279 	   && valid_vector_subparts_p (GET_MODE_NUNITS (mode)))
2280     {
2281       machine_mode inner_mode = GET_MODE_INNER (mode);
2282       tree inner_type = c_common_type_for_mode (inner_mode, unsignedp);
2283       if (inner_type != NULL_TREE)
2284 	return build_vector_type_for_mode (inner_type, mode);
2285     }
2286 
2287   if (mode == TYPE_MODE (dfloat32_type_node))
2288     return dfloat32_type_node;
2289   if (mode == TYPE_MODE (dfloat64_type_node))
2290     return dfloat64_type_node;
2291   if (mode == TYPE_MODE (dfloat128_type_node))
2292     return dfloat128_type_node;
2293 
2294   if (ALL_SCALAR_FIXED_POINT_MODE_P (mode))
2295     {
2296       if (mode == TYPE_MODE (short_fract_type_node))
2297 	return unsignedp ? sat_short_fract_type_node : short_fract_type_node;
2298       if (mode == TYPE_MODE (fract_type_node))
2299 	return unsignedp ? sat_fract_type_node : fract_type_node;
2300       if (mode == TYPE_MODE (long_fract_type_node))
2301 	return unsignedp ? sat_long_fract_type_node : long_fract_type_node;
2302       if (mode == TYPE_MODE (long_long_fract_type_node))
2303 	return unsignedp ? sat_long_long_fract_type_node
2304 			 : long_long_fract_type_node;
2305 
2306       if (mode == TYPE_MODE (unsigned_short_fract_type_node))
2307 	return unsignedp ? sat_unsigned_short_fract_type_node
2308 			 : unsigned_short_fract_type_node;
2309       if (mode == TYPE_MODE (unsigned_fract_type_node))
2310 	return unsignedp ? sat_unsigned_fract_type_node
2311 			 : unsigned_fract_type_node;
2312       if (mode == TYPE_MODE (unsigned_long_fract_type_node))
2313 	return unsignedp ? sat_unsigned_long_fract_type_node
2314 			 : unsigned_long_fract_type_node;
2315       if (mode == TYPE_MODE (unsigned_long_long_fract_type_node))
2316 	return unsignedp ? sat_unsigned_long_long_fract_type_node
2317 			 : unsigned_long_long_fract_type_node;
2318 
2319       if (mode == TYPE_MODE (short_accum_type_node))
2320 	return unsignedp ? sat_short_accum_type_node : short_accum_type_node;
2321       if (mode == TYPE_MODE (accum_type_node))
2322 	return unsignedp ? sat_accum_type_node : accum_type_node;
2323       if (mode == TYPE_MODE (long_accum_type_node))
2324 	return unsignedp ? sat_long_accum_type_node : long_accum_type_node;
2325       if (mode == TYPE_MODE (long_long_accum_type_node))
2326 	return unsignedp ? sat_long_long_accum_type_node
2327 			 : long_long_accum_type_node;
2328 
2329       if (mode == TYPE_MODE (unsigned_short_accum_type_node))
2330 	return unsignedp ? sat_unsigned_short_accum_type_node
2331 			 : unsigned_short_accum_type_node;
2332       if (mode == TYPE_MODE (unsigned_accum_type_node))
2333 	return unsignedp ? sat_unsigned_accum_type_node
2334 			 : unsigned_accum_type_node;
2335       if (mode == TYPE_MODE (unsigned_long_accum_type_node))
2336 	return unsignedp ? sat_unsigned_long_accum_type_node
2337 			 : unsigned_long_accum_type_node;
2338       if (mode == TYPE_MODE (unsigned_long_long_accum_type_node))
2339 	return unsignedp ? sat_unsigned_long_long_accum_type_node
2340 			 : unsigned_long_long_accum_type_node;
2341 
2342       if (mode == QQmode)
2343 	return unsignedp ? sat_qq_type_node : qq_type_node;
2344       if (mode == HQmode)
2345 	return unsignedp ? sat_hq_type_node : hq_type_node;
2346       if (mode == SQmode)
2347 	return unsignedp ? sat_sq_type_node : sq_type_node;
2348       if (mode == DQmode)
2349 	return unsignedp ? sat_dq_type_node : dq_type_node;
2350       if (mode == TQmode)
2351 	return unsignedp ? sat_tq_type_node : tq_type_node;
2352 
2353       if (mode == UQQmode)
2354 	return unsignedp ? sat_uqq_type_node : uqq_type_node;
2355       if (mode == UHQmode)
2356 	return unsignedp ? sat_uhq_type_node : uhq_type_node;
2357       if (mode == USQmode)
2358 	return unsignedp ? sat_usq_type_node : usq_type_node;
2359       if (mode == UDQmode)
2360 	return unsignedp ? sat_udq_type_node : udq_type_node;
2361       if (mode == UTQmode)
2362 	return unsignedp ? sat_utq_type_node : utq_type_node;
2363 
2364       if (mode == HAmode)
2365 	return unsignedp ? sat_ha_type_node : ha_type_node;
2366       if (mode == SAmode)
2367 	return unsignedp ? sat_sa_type_node : sa_type_node;
2368       if (mode == DAmode)
2369 	return unsignedp ? sat_da_type_node : da_type_node;
2370       if (mode == TAmode)
2371 	return unsignedp ? sat_ta_type_node : ta_type_node;
2372 
2373       if (mode == UHAmode)
2374 	return unsignedp ? sat_uha_type_node : uha_type_node;
2375       if (mode == USAmode)
2376 	return unsignedp ? sat_usa_type_node : usa_type_node;
2377       if (mode == UDAmode)
2378 	return unsignedp ? sat_uda_type_node : uda_type_node;
2379       if (mode == UTAmode)
2380 	return unsignedp ? sat_uta_type_node : uta_type_node;
2381     }
2382 
2383   for (t = registered_builtin_types; t; t = TREE_CHAIN (t))
2384     if (TYPE_MODE (TREE_VALUE (t)) == mode
2385 	&& !!unsignedp == !!TYPE_UNSIGNED (TREE_VALUE (t)))
2386       return TREE_VALUE (t);
2387 
2388   return NULL_TREE;
2389 }
2390 
2391 tree
2392 c_common_unsigned_type (tree type)
2393 {
2394   return c_common_signed_or_unsigned_type (1, type);
2395 }
2396 
2397 /* Return a signed type the same as TYPE in other respects.  */
2398 
2399 tree
2400 c_common_signed_type (tree type)
2401 {
2402   return c_common_signed_or_unsigned_type (0, type);
2403 }
2404 
2405 /* Return a type the same as TYPE except unsigned or
2406    signed according to UNSIGNEDP.  */
2407 
2408 tree
2409 c_common_signed_or_unsigned_type (int unsignedp, tree type)
2410 {
2411   tree type1;
2412   int i;
2413 
2414   /* This block of code emulates the behavior of the old
2415      c_common_unsigned_type. In particular, it returns
2416      long_unsigned_type_node if passed a long, even when a int would
2417      have the same size. This is necessary for warnings to work
2418      correctly in archs where sizeof(int) == sizeof(long) */
2419 
2420   type1 = TYPE_MAIN_VARIANT (type);
2421   if (type1 == signed_char_type_node || type1 == char_type_node || type1 == unsigned_char_type_node)
2422     return unsignedp ? unsigned_char_type_node : signed_char_type_node;
2423   if (type1 == integer_type_node || type1 == unsigned_type_node)
2424     return unsignedp ? unsigned_type_node : integer_type_node;
2425   if (type1 == short_integer_type_node || type1 == short_unsigned_type_node)
2426     return unsignedp ? short_unsigned_type_node : short_integer_type_node;
2427   if (type1 == long_integer_type_node || type1 == long_unsigned_type_node)
2428     return unsignedp ? long_unsigned_type_node : long_integer_type_node;
2429   if (type1 == long_long_integer_type_node || type1 == long_long_unsigned_type_node)
2430     return unsignedp ? long_long_unsigned_type_node : long_long_integer_type_node;
2431 
2432   for (i = 0; i < NUM_INT_N_ENTS; i ++)
2433     if (int_n_enabled_p[i]
2434 	&& (type1 == int_n_trees[i].unsigned_type
2435 	    || type1 == int_n_trees[i].signed_type))
2436       return (unsignedp ? int_n_trees[i].unsigned_type
2437 	      : int_n_trees[i].signed_type);
2438 
2439 #if HOST_BITS_PER_WIDE_INT >= 64
2440   if (type1 == intTI_type_node || type1 == unsigned_intTI_type_node)
2441     return unsignedp ? unsigned_intTI_type_node : intTI_type_node;
2442 #endif
2443   if (type1 == intDI_type_node || type1 == unsigned_intDI_type_node)
2444     return unsignedp ? unsigned_intDI_type_node : intDI_type_node;
2445   if (type1 == intSI_type_node || type1 == unsigned_intSI_type_node)
2446     return unsignedp ? unsigned_intSI_type_node : intSI_type_node;
2447   if (type1 == intHI_type_node || type1 == unsigned_intHI_type_node)
2448     return unsignedp ? unsigned_intHI_type_node : intHI_type_node;
2449   if (type1 == intQI_type_node || type1 == unsigned_intQI_type_node)
2450     return unsignedp ? unsigned_intQI_type_node : intQI_type_node;
2451 
2452 #define C_COMMON_FIXED_TYPES(NAME)	    \
2453   if (type1 == short_ ## NAME ## _type_node \
2454       || type1 == unsigned_short_ ## NAME ## _type_node) \
2455     return unsignedp ? unsigned_short_ ## NAME ## _type_node \
2456 		     : short_ ## NAME ## _type_node; \
2457   if (type1 == NAME ## _type_node \
2458       || type1 == unsigned_ ## NAME ## _type_node) \
2459     return unsignedp ? unsigned_ ## NAME ## _type_node \
2460 		     : NAME ## _type_node; \
2461   if (type1 == long_ ## NAME ## _type_node \
2462       || type1 == unsigned_long_ ## NAME ## _type_node) \
2463     return unsignedp ? unsigned_long_ ## NAME ## _type_node \
2464 		     : long_ ## NAME ## _type_node; \
2465   if (type1 == long_long_ ## NAME ## _type_node \
2466       || type1 == unsigned_long_long_ ## NAME ## _type_node) \
2467     return unsignedp ? unsigned_long_long_ ## NAME ## _type_node \
2468 		     : long_long_ ## NAME ## _type_node;
2469 
2470 #define C_COMMON_FIXED_MODE_TYPES(NAME) \
2471   if (type1 == NAME ## _type_node \
2472       || type1 == u ## NAME ## _type_node) \
2473     return unsignedp ? u ## NAME ## _type_node \
2474 		     : NAME ## _type_node;
2475 
2476 #define C_COMMON_FIXED_TYPES_SAT(NAME) \
2477   if (type1 == sat_ ## short_ ## NAME ## _type_node \
2478       || type1 == sat_ ## unsigned_short_ ## NAME ## _type_node) \
2479     return unsignedp ? sat_ ## unsigned_short_ ## NAME ## _type_node \
2480 		     : sat_ ## short_ ## NAME ## _type_node; \
2481   if (type1 == sat_ ## NAME ## _type_node \
2482       || type1 == sat_ ## unsigned_ ## NAME ## _type_node) \
2483     return unsignedp ? sat_ ## unsigned_ ## NAME ## _type_node \
2484 		     : sat_ ## NAME ## _type_node; \
2485   if (type1 == sat_ ## long_ ## NAME ## _type_node \
2486       || type1 == sat_ ## unsigned_long_ ## NAME ## _type_node) \
2487     return unsignedp ? sat_ ## unsigned_long_ ## NAME ## _type_node \
2488 		     : sat_ ## long_ ## NAME ## _type_node; \
2489   if (type1 == sat_ ## long_long_ ## NAME ## _type_node \
2490       || type1 == sat_ ## unsigned_long_long_ ## NAME ## _type_node) \
2491     return unsignedp ? sat_ ## unsigned_long_long_ ## NAME ## _type_node \
2492 		     : sat_ ## long_long_ ## NAME ## _type_node;
2493 
2494 #define C_COMMON_FIXED_MODE_TYPES_SAT(NAME)	\
2495   if (type1 == sat_ ## NAME ## _type_node \
2496       || type1 == sat_ ## u ## NAME ## _type_node) \
2497     return unsignedp ? sat_ ## u ## NAME ## _type_node \
2498 		     : sat_ ## NAME ## _type_node;
2499 
2500   C_COMMON_FIXED_TYPES (fract);
2501   C_COMMON_FIXED_TYPES_SAT (fract);
2502   C_COMMON_FIXED_TYPES (accum);
2503   C_COMMON_FIXED_TYPES_SAT (accum);
2504 
2505   C_COMMON_FIXED_MODE_TYPES (qq);
2506   C_COMMON_FIXED_MODE_TYPES (hq);
2507   C_COMMON_FIXED_MODE_TYPES (sq);
2508   C_COMMON_FIXED_MODE_TYPES (dq);
2509   C_COMMON_FIXED_MODE_TYPES (tq);
2510   C_COMMON_FIXED_MODE_TYPES_SAT (qq);
2511   C_COMMON_FIXED_MODE_TYPES_SAT (hq);
2512   C_COMMON_FIXED_MODE_TYPES_SAT (sq);
2513   C_COMMON_FIXED_MODE_TYPES_SAT (dq);
2514   C_COMMON_FIXED_MODE_TYPES_SAT (tq);
2515   C_COMMON_FIXED_MODE_TYPES (ha);
2516   C_COMMON_FIXED_MODE_TYPES (sa);
2517   C_COMMON_FIXED_MODE_TYPES (da);
2518   C_COMMON_FIXED_MODE_TYPES (ta);
2519   C_COMMON_FIXED_MODE_TYPES_SAT (ha);
2520   C_COMMON_FIXED_MODE_TYPES_SAT (sa);
2521   C_COMMON_FIXED_MODE_TYPES_SAT (da);
2522   C_COMMON_FIXED_MODE_TYPES_SAT (ta);
2523 
2524   /* For ENUMERAL_TYPEs in C++, must check the mode of the types, not
2525      the precision; they have precision set to match their range, but
2526      may use a wider mode to match an ABI.  If we change modes, we may
2527      wind up with bad conversions.  For INTEGER_TYPEs in C, must check
2528      the precision as well, so as to yield correct results for
2529      bit-field types.  C++ does not have these separate bit-field
2530      types, and producing a signed or unsigned variant of an
2531      ENUMERAL_TYPE may cause other problems as well.  */
2532 
2533   if (!INTEGRAL_TYPE_P (type)
2534       || TYPE_UNSIGNED (type) == unsignedp)
2535     return type;
2536 
2537 #define TYPE_OK(node)							    \
2538   (TYPE_MODE (type) == TYPE_MODE (node)					    \
2539    && TYPE_PRECISION (type) == TYPE_PRECISION (node))
2540   if (TYPE_OK (signed_char_type_node))
2541     return unsignedp ? unsigned_char_type_node : signed_char_type_node;
2542   if (TYPE_OK (integer_type_node))
2543     return unsignedp ? unsigned_type_node : integer_type_node;
2544   if (TYPE_OK (short_integer_type_node))
2545     return unsignedp ? short_unsigned_type_node : short_integer_type_node;
2546   if (TYPE_OK (long_integer_type_node))
2547     return unsignedp ? long_unsigned_type_node : long_integer_type_node;
2548   if (TYPE_OK (long_long_integer_type_node))
2549     return (unsignedp ? long_long_unsigned_type_node
2550 	    : long_long_integer_type_node);
2551 
2552   for (i = 0; i < NUM_INT_N_ENTS; i ++)
2553     if (int_n_enabled_p[i]
2554 	&& TYPE_MODE (type) == int_n_data[i].m
2555 	&& TYPE_PRECISION (type) == int_n_data[i].bitsize)
2556       return (unsignedp ? int_n_trees[i].unsigned_type
2557 	      : int_n_trees[i].signed_type);
2558 
2559 #if HOST_BITS_PER_WIDE_INT >= 64
2560   if (TYPE_OK (intTI_type_node))
2561     return unsignedp ? unsigned_intTI_type_node : intTI_type_node;
2562 #endif
2563   if (TYPE_OK (intDI_type_node))
2564     return unsignedp ? unsigned_intDI_type_node : intDI_type_node;
2565   if (TYPE_OK (intSI_type_node))
2566     return unsignedp ? unsigned_intSI_type_node : intSI_type_node;
2567   if (TYPE_OK (intHI_type_node))
2568     return unsignedp ? unsigned_intHI_type_node : intHI_type_node;
2569   if (TYPE_OK (intQI_type_node))
2570     return unsignedp ? unsigned_intQI_type_node : intQI_type_node;
2571 #undef TYPE_OK
2572 
2573   return build_nonstandard_integer_type (TYPE_PRECISION (type), unsignedp);
2574 }
2575 
2576 /* Build a bit-field integer type for the given WIDTH and UNSIGNEDP.  */
2577 
2578 tree
2579 c_build_bitfield_integer_type (unsigned HOST_WIDE_INT width, int unsignedp)
2580 {
2581   int i;
2582 
2583   /* Extended integer types of the same width as a standard type have
2584      lesser rank, so those of the same width as int promote to int or
2585      unsigned int and are valid for printf formats expecting int or
2586      unsigned int.  To avoid such special cases, avoid creating
2587      extended integer types for bit-fields if a standard integer type
2588      is available.  */
2589   if (width == TYPE_PRECISION (integer_type_node))
2590     return unsignedp ? unsigned_type_node : integer_type_node;
2591   if (width == TYPE_PRECISION (signed_char_type_node))
2592     return unsignedp ? unsigned_char_type_node : signed_char_type_node;
2593   if (width == TYPE_PRECISION (short_integer_type_node))
2594     return unsignedp ? short_unsigned_type_node : short_integer_type_node;
2595   if (width == TYPE_PRECISION (long_integer_type_node))
2596     return unsignedp ? long_unsigned_type_node : long_integer_type_node;
2597   if (width == TYPE_PRECISION (long_long_integer_type_node))
2598     return (unsignedp ? long_long_unsigned_type_node
2599 	    : long_long_integer_type_node);
2600   for (i = 0; i < NUM_INT_N_ENTS; i ++)
2601     if (int_n_enabled_p[i]
2602 	&& width == int_n_data[i].bitsize)
2603       return (unsignedp ? int_n_trees[i].unsigned_type
2604 	      : int_n_trees[i].signed_type);
2605   return build_nonstandard_integer_type (width, unsignedp);
2606 }
2607 
2608 /* The C version of the register_builtin_type langhook.  */
2609 
2610 void
2611 c_register_builtin_type (tree type, const char* name)
2612 {
2613   tree decl;
2614 
2615   decl = build_decl (UNKNOWN_LOCATION,
2616 		     TYPE_DECL, get_identifier (name), type);
2617   DECL_ARTIFICIAL (decl) = 1;
2618   if (!TYPE_NAME (type))
2619     TYPE_NAME (type) = decl;
2620   lang_hooks.decls.pushdecl (decl);
2621 
2622   registered_builtin_types = tree_cons (0, type, registered_builtin_types);
2623 }
2624 
2625 /* Print an error message for invalid operands to arith operation
2626    CODE with TYPE0 for operand 0, and TYPE1 for operand 1.
2627    RICHLOC is a rich location for the message, containing either
2628    three separate locations for each of the operator and operands
2629 
2630       lhs op rhs
2631       ~~~ ^~ ~~~
2632 
2633    (C FE), or one location ranging over all over them
2634 
2635       lhs op rhs
2636       ~~~~^~~~~~
2637 
2638    (C++ FE).  */
2639 
2640 void
2641 binary_op_error (rich_location *richloc, enum tree_code code,
2642 		 tree type0, tree type1)
2643 {
2644   const char *opname;
2645 
2646   switch (code)
2647     {
2648     case PLUS_EXPR:
2649       opname = "+"; break;
2650     case MINUS_EXPR:
2651       opname = "-"; break;
2652     case MULT_EXPR:
2653       opname = "*"; break;
2654     case MAX_EXPR:
2655       opname = "max"; break;
2656     case MIN_EXPR:
2657       opname = "min"; break;
2658     case EQ_EXPR:
2659       opname = "=="; break;
2660     case NE_EXPR:
2661       opname = "!="; break;
2662     case LE_EXPR:
2663       opname = "<="; break;
2664     case GE_EXPR:
2665       opname = ">="; break;
2666     case LT_EXPR:
2667       opname = "<"; break;
2668     case GT_EXPR:
2669       opname = ">"; break;
2670     case LSHIFT_EXPR:
2671       opname = "<<"; break;
2672     case RSHIFT_EXPR:
2673       opname = ">>"; break;
2674     case TRUNC_MOD_EXPR:
2675     case FLOOR_MOD_EXPR:
2676       opname = "%"; break;
2677     case TRUNC_DIV_EXPR:
2678     case FLOOR_DIV_EXPR:
2679       opname = "/"; break;
2680     case BIT_AND_EXPR:
2681       opname = "&"; break;
2682     case BIT_IOR_EXPR:
2683       opname = "|"; break;
2684     case TRUTH_ANDIF_EXPR:
2685       opname = "&&"; break;
2686     case TRUTH_ORIF_EXPR:
2687       opname = "||"; break;
2688     case BIT_XOR_EXPR:
2689       opname = "^"; break;
2690     default:
2691       gcc_unreachable ();
2692     }
2693   error_at (richloc,
2694 	    "invalid operands to binary %s (have %qT and %qT)",
2695 	    opname, type0, type1);
2696 }
2697 
2698 /* Given an expression as a tree, return its original type.  Do this
2699    by stripping any conversion that preserves the sign and precision.  */
2700 static tree
2701 expr_original_type (tree expr)
2702 {
2703   STRIP_SIGN_NOPS (expr);
2704   return TREE_TYPE (expr);
2705 }
2706 
2707 /* Subroutine of build_binary_op, used for comparison operations.
2708    See if the operands have both been converted from subword integer types
2709    and, if so, perhaps change them both back to their original type.
2710    This function is also responsible for converting the two operands
2711    to the proper common type for comparison.
2712 
2713    The arguments of this function are all pointers to local variables
2714    of build_binary_op: OP0_PTR is &OP0, OP1_PTR is &OP1,
2715    RESTYPE_PTR is &RESULT_TYPE and RESCODE_PTR is &RESULTCODE.
2716 
2717    LOC is the location of the comparison.
2718 
2719    If this function returns non-NULL_TREE, it means that the comparison has
2720    a constant value.  What this function returns is an expression for
2721    that value.  */
2722 
2723 tree
2724 shorten_compare (location_t loc, tree *op0_ptr, tree *op1_ptr,
2725 		 tree *restype_ptr, enum tree_code *rescode_ptr)
2726 {
2727   tree type;
2728   tree op0 = *op0_ptr;
2729   tree op1 = *op1_ptr;
2730   int unsignedp0, unsignedp1;
2731   int real1, real2;
2732   tree primop0, primop1;
2733   enum tree_code code = *rescode_ptr;
2734 
2735   /* Throw away any conversions to wider types
2736      already present in the operands.  */
2737 
2738   primop0 = c_common_get_narrower (op0, &unsignedp0);
2739   primop1 = c_common_get_narrower (op1, &unsignedp1);
2740 
2741   /* If primopN is first sign-extended from primopN's precision to opN's
2742      precision, then zero-extended from opN's precision to
2743      *restype_ptr precision, shortenings might be invalid.  */
2744   if (TYPE_PRECISION (TREE_TYPE (primop0)) < TYPE_PRECISION (TREE_TYPE (op0))
2745       && TYPE_PRECISION (TREE_TYPE (op0)) < TYPE_PRECISION (*restype_ptr)
2746       && !unsignedp0
2747       && TYPE_UNSIGNED (TREE_TYPE (op0)))
2748     primop0 = op0;
2749   if (TYPE_PRECISION (TREE_TYPE (primop1)) < TYPE_PRECISION (TREE_TYPE (op1))
2750       && TYPE_PRECISION (TREE_TYPE (op1)) < TYPE_PRECISION (*restype_ptr)
2751       && !unsignedp1
2752       && TYPE_UNSIGNED (TREE_TYPE (op1)))
2753     primop1 = op1;
2754 
2755   /* Handle the case that OP0 does not *contain* a conversion
2756      but it *requires* conversion to FINAL_TYPE.  */
2757 
2758   if (op0 == primop0 && TREE_TYPE (op0) != *restype_ptr)
2759     unsignedp0 = TYPE_UNSIGNED (TREE_TYPE (op0));
2760   if (op1 == primop1 && TREE_TYPE (op1) != *restype_ptr)
2761     unsignedp1 = TYPE_UNSIGNED (TREE_TYPE (op1));
2762 
2763   /* If one of the operands must be floated, we cannot optimize.  */
2764   real1 = TREE_CODE (TREE_TYPE (primop0)) == REAL_TYPE;
2765   real2 = TREE_CODE (TREE_TYPE (primop1)) == REAL_TYPE;
2766 
2767   /* If first arg is constant, swap the args (changing operation
2768      so value is preserved), for canonicalization.  Don't do this if
2769      the second arg is 0.  */
2770 
2771   if (TREE_CONSTANT (primop0)
2772       && !integer_zerop (primop1) && !real_zerop (primop1)
2773       && !fixed_zerop (primop1))
2774     {
2775       std::swap (primop0, primop1);
2776       std::swap (op0, op1);
2777       *op0_ptr = op0;
2778       *op1_ptr = op1;
2779       std::swap (unsignedp0, unsignedp1);
2780       std::swap (real1, real2);
2781 
2782       switch (code)
2783 	{
2784 	case LT_EXPR:
2785 	  code = GT_EXPR;
2786 	  break;
2787 	case GT_EXPR:
2788 	  code = LT_EXPR;
2789 	  break;
2790 	case LE_EXPR:
2791 	  code = GE_EXPR;
2792 	  break;
2793 	case GE_EXPR:
2794 	  code = LE_EXPR;
2795 	  break;
2796 	default:
2797 	  break;
2798 	}
2799       *rescode_ptr = code;
2800     }
2801 
2802   /* If comparing an integer against a constant more bits wide,
2803      maybe we can deduce a value of 1 or 0 independent of the data.
2804      Or else truncate the constant now
2805      rather than extend the variable at run time.
2806 
2807      This is only interesting if the constant is the wider arg.
2808      Also, it is not safe if the constant is unsigned and the
2809      variable arg is signed, since in this case the variable
2810      would be sign-extended and then regarded as unsigned.
2811      Our technique fails in this case because the lowest/highest
2812      possible unsigned results don't follow naturally from the
2813      lowest/highest possible values of the variable operand.
2814      For just EQ_EXPR and NE_EXPR there is another technique that
2815      could be used: see if the constant can be faithfully represented
2816      in the other operand's type, by truncating it and reextending it
2817      and see if that preserves the constant's value.  */
2818 
2819   if (!real1 && !real2
2820       && TREE_CODE (TREE_TYPE (primop0)) != FIXED_POINT_TYPE
2821       && TREE_CODE (primop1) == INTEGER_CST
2822       && TYPE_PRECISION (TREE_TYPE (primop0)) < TYPE_PRECISION (*restype_ptr))
2823     {
2824       int min_gt, max_gt, min_lt, max_lt;
2825       tree maxval, minval;
2826       /* 1 if comparison is nominally unsigned.  */
2827       int unsignedp = TYPE_UNSIGNED (*restype_ptr);
2828       tree val;
2829 
2830       type = c_common_signed_or_unsigned_type (unsignedp0,
2831 					       TREE_TYPE (primop0));
2832 
2833       maxval = TYPE_MAX_VALUE (type);
2834       minval = TYPE_MIN_VALUE (type);
2835 
2836       if (unsignedp && !unsignedp0)
2837 	*restype_ptr = c_common_signed_type (*restype_ptr);
2838 
2839       if (TREE_TYPE (primop1) != *restype_ptr)
2840 	{
2841 	  /* Convert primop1 to target type, but do not introduce
2842 	     additional overflow.  We know primop1 is an int_cst.  */
2843 	  primop1 = force_fit_type (*restype_ptr,
2844 				    wi::to_wide
2845 				     (primop1,
2846 				      TYPE_PRECISION (*restype_ptr)),
2847 				    0, TREE_OVERFLOW (primop1));
2848 	}
2849       if (type != *restype_ptr)
2850 	{
2851 	  minval = convert (*restype_ptr, minval);
2852 	  maxval = convert (*restype_ptr, maxval);
2853 	}
2854 
2855       min_gt = tree_int_cst_lt (primop1, minval);
2856       max_gt = tree_int_cst_lt (primop1, maxval);
2857       min_lt = tree_int_cst_lt (minval, primop1);
2858       max_lt = tree_int_cst_lt (maxval, primop1);
2859 
2860       val = 0;
2861       /* This used to be a switch, but Genix compiler can't handle that.  */
2862       if (code == NE_EXPR)
2863 	{
2864 	  if (max_lt || min_gt)
2865 	    val = truthvalue_true_node;
2866 	}
2867       else if (code == EQ_EXPR)
2868 	{
2869 	  if (max_lt || min_gt)
2870 	    val = truthvalue_false_node;
2871 	}
2872       else if (code == LT_EXPR)
2873 	{
2874 	  if (max_lt)
2875 	    val = truthvalue_true_node;
2876 	  if (!min_lt)
2877 	    val = truthvalue_false_node;
2878 	}
2879       else if (code == GT_EXPR)
2880 	{
2881 	  if (min_gt)
2882 	    val = truthvalue_true_node;
2883 	  if (!max_gt)
2884 	    val = truthvalue_false_node;
2885 	}
2886       else if (code == LE_EXPR)
2887 	{
2888 	  if (!max_gt)
2889 	    val = truthvalue_true_node;
2890 	  if (min_gt)
2891 	    val = truthvalue_false_node;
2892 	}
2893       else if (code == GE_EXPR)
2894 	{
2895 	  if (!min_lt)
2896 	    val = truthvalue_true_node;
2897 	  if (max_lt)
2898 	    val = truthvalue_false_node;
2899 	}
2900 
2901       /* If primop0 was sign-extended and unsigned comparison specd,
2902 	 we did a signed comparison above using the signed type bounds.
2903 	 But the comparison we output must be unsigned.
2904 
2905 	 Also, for inequalities, VAL is no good; but if the signed
2906 	 comparison had *any* fixed result, it follows that the
2907 	 unsigned comparison just tests the sign in reverse
2908 	 (positive values are LE, negative ones GE).
2909 	 So we can generate an unsigned comparison
2910 	 against an extreme value of the signed type.  */
2911 
2912       if (unsignedp && !unsignedp0)
2913 	{
2914 	  if (val != 0)
2915 	    switch (code)
2916 	      {
2917 	      case LT_EXPR:
2918 	      case GE_EXPR:
2919 		primop1 = TYPE_MIN_VALUE (type);
2920 		val = 0;
2921 		break;
2922 
2923 	      case LE_EXPR:
2924 	      case GT_EXPR:
2925 		primop1 = TYPE_MAX_VALUE (type);
2926 		val = 0;
2927 		break;
2928 
2929 	      default:
2930 		break;
2931 	      }
2932 	  type = c_common_unsigned_type (type);
2933 	}
2934 
2935       if (TREE_CODE (primop0) != INTEGER_CST
2936 	  /* Don't warn if it's from a (non-system) macro.  */
2937 	  && !(from_macro_expansion_at
2938 	       (expansion_point_location_if_in_system_header
2939 		(EXPR_LOCATION (primop0)))))
2940 	{
2941 	  if (val == truthvalue_false_node)
2942 	    warning_at (loc, OPT_Wtype_limits,
2943 			"comparison is always false due to limited range of data type");
2944 	  if (val == truthvalue_true_node)
2945 	    warning_at (loc, OPT_Wtype_limits,
2946 			"comparison is always true due to limited range of data type");
2947 	}
2948 
2949       if (val != 0)
2950 	{
2951 	  /* Don't forget to evaluate PRIMOP0 if it has side effects.  */
2952 	  if (TREE_SIDE_EFFECTS (primop0))
2953 	    return build2 (COMPOUND_EXPR, TREE_TYPE (val), primop0, val);
2954 	  return val;
2955 	}
2956 
2957       /* Value is not predetermined, but do the comparison
2958 	 in the type of the operand that is not constant.
2959 	 TYPE is already properly set.  */
2960     }
2961 
2962   /* If either arg is decimal float and the other is float, find the
2963      proper common type to use for comparison.  */
2964   else if (real1 && real2
2965 	   && DECIMAL_FLOAT_MODE_P (TYPE_MODE (TREE_TYPE (primop0)))
2966 	   && DECIMAL_FLOAT_MODE_P (TYPE_MODE (TREE_TYPE (primop1))))
2967     type = common_type (TREE_TYPE (primop0), TREE_TYPE (primop1));
2968 
2969   /* If either arg is decimal float and the other is float, fail.  */
2970   else if (real1 && real2
2971 	   && (DECIMAL_FLOAT_MODE_P (TYPE_MODE (TREE_TYPE (primop0)))
2972 	       || DECIMAL_FLOAT_MODE_P (TYPE_MODE (TREE_TYPE (primop1)))))
2973     return NULL_TREE;
2974 
2975   else if (real1 && real2
2976 	   && (TYPE_PRECISION (TREE_TYPE (primop0))
2977 	       == TYPE_PRECISION (TREE_TYPE (primop1))))
2978     type = TREE_TYPE (primop0);
2979 
2980   /* If args' natural types are both narrower than nominal type
2981      and both extend in the same manner, compare them
2982      in the type of the wider arg.
2983      Otherwise must actually extend both to the nominal
2984      common type lest different ways of extending
2985      alter the result.
2986      (eg, (short)-1 == (unsigned short)-1  should be 0.)  */
2987 
2988   else if (unsignedp0 == unsignedp1 && real1 == real2
2989 	   && TYPE_PRECISION (TREE_TYPE (primop0)) < TYPE_PRECISION (*restype_ptr)
2990 	   && TYPE_PRECISION (TREE_TYPE (primop1)) < TYPE_PRECISION (*restype_ptr))
2991     {
2992       type = common_type (TREE_TYPE (primop0), TREE_TYPE (primop1));
2993       type = c_common_signed_or_unsigned_type (unsignedp0
2994 					       || TYPE_UNSIGNED (*restype_ptr),
2995 					       type);
2996       /* Make sure shorter operand is extended the right way
2997 	 to match the longer operand.  */
2998       primop0
2999 	= convert (c_common_signed_or_unsigned_type (unsignedp0,
3000 						     TREE_TYPE (primop0)),
3001 		   primop0);
3002       primop1
3003 	= convert (c_common_signed_or_unsigned_type (unsignedp1,
3004 						     TREE_TYPE (primop1)),
3005 		   primop1);
3006     }
3007   else
3008     {
3009       /* Here we must do the comparison on the nominal type
3010 	 using the args exactly as we received them.  */
3011       type = *restype_ptr;
3012       primop0 = op0;
3013       primop1 = op1;
3014 
3015       if (!real1 && !real2 && integer_zerop (primop1)
3016 	  && TYPE_UNSIGNED (*restype_ptr))
3017 	{
3018 	  tree value = NULL_TREE;
3019 	  /* All unsigned values are >= 0, so we warn.  However,
3020 	     if OP0 is a constant that is >= 0, the signedness of
3021 	     the comparison isn't an issue, so suppress the
3022 	     warning.  */
3023 	  bool warn =
3024 	    warn_type_limits && !in_system_header_at (loc)
3025 	    && !(TREE_CODE (primop0) == INTEGER_CST
3026 		 && !TREE_OVERFLOW (convert (c_common_signed_type (type),
3027 					     primop0)))
3028 	    /* Do not warn for enumeration types.  */
3029 	    && (TREE_CODE (expr_original_type (primop0)) != ENUMERAL_TYPE);
3030 
3031 	  switch (code)
3032 	    {
3033 	    case GE_EXPR:
3034 	      if (warn)
3035 		warning_at (loc, OPT_Wtype_limits,
3036 			    "comparison of unsigned expression >= 0 is always true");
3037 	      value = truthvalue_true_node;
3038 	      break;
3039 
3040 	    case LT_EXPR:
3041 	      if (warn)
3042 		warning_at (loc, OPT_Wtype_limits,
3043 			    "comparison of unsigned expression < 0 is always false");
3044 	      value = truthvalue_false_node;
3045 	      break;
3046 
3047 	    default:
3048 	      break;
3049 	    }
3050 
3051 	  if (value != NULL_TREE)
3052 	    {
3053 	      /* Don't forget to evaluate PRIMOP0 if it has side effects.  */
3054 	      if (TREE_SIDE_EFFECTS (primop0))
3055 		return build2 (COMPOUND_EXPR, TREE_TYPE (value),
3056 			       primop0, value);
3057 	      return value;
3058 	    }
3059 	}
3060     }
3061 
3062   *op0_ptr = convert (type, primop0);
3063   *op1_ptr = convert (type, primop1);
3064 
3065   *restype_ptr = truthvalue_type_node;
3066 
3067   return NULL_TREE;
3068 }
3069 
3070 /* Return a tree for the sum or difference (RESULTCODE says which)
3071    of pointer PTROP and integer INTOP.  */
3072 
3073 tree
3074 pointer_int_sum (location_t loc, enum tree_code resultcode,
3075 		 tree ptrop, tree intop, bool complain)
3076 {
3077   tree size_exp, ret;
3078 
3079   /* The result is a pointer of the same type that is being added.  */
3080   tree result_type = TREE_TYPE (ptrop);
3081 
3082   if (TREE_CODE (TREE_TYPE (result_type)) == VOID_TYPE)
3083     {
3084       if (complain && warn_pointer_arith)
3085 	pedwarn (loc, OPT_Wpointer_arith,
3086 		 "pointer of type %<void *%> used in arithmetic");
3087       else if (!complain)
3088 	return error_mark_node;
3089       size_exp = integer_one_node;
3090     }
3091   else if (TREE_CODE (TREE_TYPE (result_type)) == FUNCTION_TYPE)
3092     {
3093       if (complain && warn_pointer_arith)
3094 	pedwarn (loc, OPT_Wpointer_arith,
3095 		 "pointer to a function used in arithmetic");
3096       else if (!complain)
3097 	return error_mark_node;
3098       size_exp = integer_one_node;
3099     }
3100   else
3101     size_exp = size_in_bytes_loc (loc, TREE_TYPE (result_type));
3102 
3103   /* We are manipulating pointer values, so we don't need to warn
3104      about relying on undefined signed overflow.  We disable the
3105      warning here because we use integer types so fold won't know that
3106      they are really pointers.  */
3107   fold_defer_overflow_warnings ();
3108 
3109   /* If what we are about to multiply by the size of the elements
3110      contains a constant term, apply distributive law
3111      and multiply that constant term separately.
3112      This helps produce common subexpressions.  */
3113   if ((TREE_CODE (intop) == PLUS_EXPR || TREE_CODE (intop) == MINUS_EXPR)
3114       && !TREE_CONSTANT (intop)
3115       && TREE_CONSTANT (TREE_OPERAND (intop, 1))
3116       && TREE_CONSTANT (size_exp)
3117       /* If the constant comes from pointer subtraction,
3118 	 skip this optimization--it would cause an error.  */
3119       && TREE_CODE (TREE_TYPE (TREE_OPERAND (intop, 0))) == INTEGER_TYPE
3120       /* If the constant is unsigned, and smaller than the pointer size,
3121 	 then we must skip this optimization.  This is because it could cause
3122 	 an overflow error if the constant is negative but INTOP is not.  */
3123       && (!TYPE_UNSIGNED (TREE_TYPE (intop))
3124 	  || (TYPE_PRECISION (TREE_TYPE (intop))
3125 	      == TYPE_PRECISION (TREE_TYPE (ptrop)))))
3126     {
3127       enum tree_code subcode = resultcode;
3128       tree int_type = TREE_TYPE (intop);
3129       if (TREE_CODE (intop) == MINUS_EXPR)
3130 	subcode = (subcode == PLUS_EXPR ? MINUS_EXPR : PLUS_EXPR);
3131       /* Convert both subexpression types to the type of intop,
3132 	 because weird cases involving pointer arithmetic
3133 	 can result in a sum or difference with different type args.  */
3134       ptrop = build_binary_op (EXPR_LOCATION (TREE_OPERAND (intop, 1)),
3135 			       subcode, ptrop,
3136 			       convert (int_type, TREE_OPERAND (intop, 1)),
3137 			       true);
3138       intop = convert (int_type, TREE_OPERAND (intop, 0));
3139     }
3140 
3141   /* Convert the integer argument to a type the same size as sizetype
3142      so the multiply won't overflow spuriously.  */
3143   if (TYPE_PRECISION (TREE_TYPE (intop)) != TYPE_PRECISION (sizetype)
3144       || TYPE_UNSIGNED (TREE_TYPE (intop)) != TYPE_UNSIGNED (sizetype))
3145     intop = convert (c_common_type_for_size (TYPE_PRECISION (sizetype),
3146 					     TYPE_UNSIGNED (sizetype)), intop);
3147 
3148   /* Replace the integer argument with a suitable product by the object size.
3149      Do this multiplication as signed, then convert to the appropriate type
3150      for the pointer operation and disregard an overflow that occurred only
3151      because of the sign-extension change in the latter conversion.  */
3152   {
3153     tree t = fold_build2_loc (loc, MULT_EXPR, TREE_TYPE (intop), intop,
3154 			      convert (TREE_TYPE (intop), size_exp));
3155     intop = convert (sizetype, t);
3156     if (TREE_OVERFLOW_P (intop) && !TREE_OVERFLOW (t))
3157       intop = wide_int_to_tree (TREE_TYPE (intop), wi::to_wide (intop));
3158   }
3159 
3160   /* Create the sum or difference.  */
3161   if (resultcode == MINUS_EXPR)
3162     intop = fold_build1_loc (loc, NEGATE_EXPR, sizetype, intop);
3163 
3164   ret = fold_build_pointer_plus_loc (loc, ptrop, intop);
3165 
3166   fold_undefer_and_ignore_overflow_warnings ();
3167 
3168   return ret;
3169 }
3170 
3171 /* Wrap a C_MAYBE_CONST_EXPR around an expression that is fully folded
3172    and if NON_CONST is known not to be permitted in an evaluated part
3173    of a constant expression.  */
3174 
3175 tree
3176 c_wrap_maybe_const (tree expr, bool non_const)
3177 {
3178   bool nowarning = TREE_NO_WARNING (expr);
3179   location_t loc = EXPR_LOCATION (expr);
3180 
3181   /* This should never be called for C++.  */
3182   if (c_dialect_cxx ())
3183     gcc_unreachable ();
3184 
3185   /* The result of folding may have a NOP_EXPR to set TREE_NO_WARNING.  */
3186   STRIP_TYPE_NOPS (expr);
3187   expr = build2 (C_MAYBE_CONST_EXPR, TREE_TYPE (expr), NULL, expr);
3188   C_MAYBE_CONST_EXPR_NON_CONST (expr) = non_const;
3189   if (nowarning)
3190     TREE_NO_WARNING (expr) = 1;
3191   protected_set_expr_location (expr, loc);
3192 
3193   return expr;
3194 }
3195 
3196 /* Return whether EXPR is a declaration whose address can never be
3197    NULL.  */
3198 
3199 bool
3200 decl_with_nonnull_addr_p (const_tree expr)
3201 {
3202   return (DECL_P (expr)
3203 	  && (TREE_CODE (expr) == PARM_DECL
3204 	      || TREE_CODE (expr) == LABEL_DECL
3205 	      || !DECL_WEAK (expr)));
3206 }
3207 
3208 /* Prepare expr to be an argument of a TRUTH_NOT_EXPR,
3209    or for an `if' or `while' statement or ?..: exp.  It should already
3210    have been validated to be of suitable type; otherwise, a bad
3211    diagnostic may result.
3212 
3213    The EXPR is located at LOCATION.
3214 
3215    This preparation consists of taking the ordinary
3216    representation of an expression expr and producing a valid tree
3217    boolean expression describing whether expr is nonzero.  We could
3218    simply always do build_binary_op (NE_EXPR, expr, truthvalue_false_node, 1),
3219    but we optimize comparisons, &&, ||, and !.
3220 
3221    The resulting type should always be `truthvalue_type_node'.  */
3222 
3223 tree
3224 c_common_truthvalue_conversion (location_t location, tree expr)
3225 {
3226   switch (TREE_CODE (expr))
3227     {
3228     case EQ_EXPR:   case NE_EXPR:   case UNEQ_EXPR: case LTGT_EXPR:
3229     case LE_EXPR:   case GE_EXPR:   case LT_EXPR:   case GT_EXPR:
3230     case UNLE_EXPR: case UNGE_EXPR: case UNLT_EXPR: case UNGT_EXPR:
3231     case ORDERED_EXPR: case UNORDERED_EXPR:
3232       if (TREE_TYPE (expr) == truthvalue_type_node)
3233 	return expr;
3234       expr = build2 (TREE_CODE (expr), truthvalue_type_node,
3235 		     TREE_OPERAND (expr, 0), TREE_OPERAND (expr, 1));
3236       goto ret;
3237 
3238     case TRUTH_ANDIF_EXPR:
3239     case TRUTH_ORIF_EXPR:
3240     case TRUTH_AND_EXPR:
3241     case TRUTH_OR_EXPR:
3242     case TRUTH_XOR_EXPR:
3243       if (TREE_TYPE (expr) == truthvalue_type_node)
3244 	return expr;
3245       expr = build2 (TREE_CODE (expr), truthvalue_type_node,
3246 		     c_common_truthvalue_conversion (location,
3247 						     TREE_OPERAND (expr, 0)),
3248 		     c_common_truthvalue_conversion (location,
3249 						     TREE_OPERAND (expr, 1)));
3250       goto ret;
3251 
3252     case TRUTH_NOT_EXPR:
3253       if (TREE_TYPE (expr) == truthvalue_type_node)
3254 	return expr;
3255       expr = build1 (TREE_CODE (expr), truthvalue_type_node,
3256 		     c_common_truthvalue_conversion (location,
3257 						     TREE_OPERAND (expr, 0)));
3258       goto ret;
3259 
3260     case ERROR_MARK:
3261       return expr;
3262 
3263     case INTEGER_CST:
3264       if (TREE_CODE (TREE_TYPE (expr)) == ENUMERAL_TYPE
3265 	  && !integer_zerop (expr)
3266 	  && !integer_onep (expr))
3267 	warning_at (location, OPT_Wint_in_bool_context,
3268 		    "enum constant in boolean context");
3269       return integer_zerop (expr) ? truthvalue_false_node
3270 				  : truthvalue_true_node;
3271 
3272     case REAL_CST:
3273       return real_compare (NE_EXPR, &TREE_REAL_CST (expr), &dconst0)
3274 	     ? truthvalue_true_node
3275 	     : truthvalue_false_node;
3276 
3277     case FIXED_CST:
3278       return fixed_compare (NE_EXPR, &TREE_FIXED_CST (expr),
3279 			    &FCONST0 (TYPE_MODE (TREE_TYPE (expr))))
3280 	     ? truthvalue_true_node
3281 	     : truthvalue_false_node;
3282 
3283     case FUNCTION_DECL:
3284       expr = build_unary_op (location, ADDR_EXPR, expr, false);
3285       /* Fall through.  */
3286 
3287     case ADDR_EXPR:
3288       {
3289  	tree inner = TREE_OPERAND (expr, 0);
3290 	if (decl_with_nonnull_addr_p (inner))
3291 	  {
3292 	    /* Common Ada/Pascal programmer's mistake.  */
3293 	    warning_at (location,
3294 			OPT_Waddress,
3295 			"the address of %qD will always evaluate as %<true%>",
3296 			inner);
3297 	    return truthvalue_true_node;
3298 	  }
3299 	break;
3300       }
3301 
3302     case COMPLEX_EXPR:
3303       expr = build_binary_op (EXPR_LOCATION (expr),
3304 			      (TREE_SIDE_EFFECTS (TREE_OPERAND (expr, 1))
3305 			       ? TRUTH_OR_EXPR : TRUTH_ORIF_EXPR),
3306 		c_common_truthvalue_conversion (location,
3307 						TREE_OPERAND (expr, 0)),
3308 		c_common_truthvalue_conversion (location,
3309 						TREE_OPERAND (expr, 1)),
3310 			      false);
3311       goto ret;
3312 
3313     case NEGATE_EXPR:
3314     case ABS_EXPR:
3315     case FLOAT_EXPR:
3316     case EXCESS_PRECISION_EXPR:
3317       /* These don't change whether an object is nonzero or zero.  */
3318       return c_common_truthvalue_conversion (location, TREE_OPERAND (expr, 0));
3319 
3320     case LROTATE_EXPR:
3321     case RROTATE_EXPR:
3322       /* These don't change whether an object is zero or nonzero, but
3323 	 we can't ignore them if their second arg has side-effects.  */
3324       if (TREE_SIDE_EFFECTS (TREE_OPERAND (expr, 1)))
3325 	{
3326 	  expr = build2 (COMPOUND_EXPR, truthvalue_type_node,
3327 			 TREE_OPERAND (expr, 1),
3328 			 c_common_truthvalue_conversion
3329 			 (location, TREE_OPERAND (expr, 0)));
3330 	  goto ret;
3331 	}
3332       else
3333 	return c_common_truthvalue_conversion (location,
3334 					       TREE_OPERAND (expr, 0));
3335 
3336     case MULT_EXPR:
3337       warning_at (EXPR_LOCATION (expr), OPT_Wint_in_bool_context,
3338 		  "%<*%> in boolean context, suggest %<&&%> instead");
3339       break;
3340 
3341     case LSHIFT_EXPR:
3342       /* We will only warn on signed shifts here, because the majority of
3343 	 false positive warnings happen in code where unsigned arithmetic
3344 	 was used in anticipation of a possible overflow.
3345 	 Furthermore, if we see an unsigned type here we know that the
3346 	 result of the shift is not subject to integer promotion rules.  */
3347       if (TREE_CODE (TREE_TYPE (expr)) == INTEGER_TYPE
3348 	  && !TYPE_UNSIGNED (TREE_TYPE (expr)))
3349 	warning_at (EXPR_LOCATION (expr), OPT_Wint_in_bool_context,
3350 		    "%<<<%> in boolean context, did you mean %<<%> ?");
3351       break;
3352 
3353     case COND_EXPR:
3354       if (warn_int_in_bool_context
3355 	  && !from_macro_definition_at (EXPR_LOCATION (expr)))
3356 	{
3357 	  tree val1 = fold_for_warn (TREE_OPERAND (expr, 1));
3358 	  tree val2 = fold_for_warn (TREE_OPERAND (expr, 2));
3359 	  if (TREE_CODE (val1) == INTEGER_CST
3360 	      && TREE_CODE (val2) == INTEGER_CST
3361 	      && !integer_zerop (val1)
3362 	      && !integer_zerop (val2)
3363 	      && (!integer_onep (val1)
3364 		  || !integer_onep (val2)))
3365 	    warning_at (EXPR_LOCATION (expr), OPT_Wint_in_bool_context,
3366 			"?: using integer constants in boolean context, "
3367 			"the expression will always evaluate to %<true%>");
3368 	  else if ((TREE_CODE (val1) == INTEGER_CST
3369 		    && !integer_zerop (val1)
3370 		    && !integer_onep (val1))
3371 		   || (TREE_CODE (val2) == INTEGER_CST
3372 		       && !integer_zerop (val2)
3373 		       && !integer_onep (val2)))
3374 	    warning_at (EXPR_LOCATION (expr), OPT_Wint_in_bool_context,
3375 			"?: using integer constants in boolean context");
3376 	}
3377       /* Distribute the conversion into the arms of a COND_EXPR.  */
3378       if (c_dialect_cxx ())
3379 	/* Avoid premature folding.  */
3380 	break;
3381       else
3382 	{
3383 	  int w = warn_int_in_bool_context;
3384 	  warn_int_in_bool_context = 0;
3385 	  /* Folding will happen later for C.  */
3386 	  expr = build3 (COND_EXPR, truthvalue_type_node,
3387 			 TREE_OPERAND (expr, 0),
3388 			 c_common_truthvalue_conversion (location,
3389 							 TREE_OPERAND (expr, 1)),
3390 			 c_common_truthvalue_conversion (location,
3391 							 TREE_OPERAND (expr, 2)));
3392 	  warn_int_in_bool_context = w;
3393 	  goto ret;
3394 	}
3395 
3396     CASE_CONVERT:
3397       {
3398 	tree totype = TREE_TYPE (expr);
3399 	tree fromtype = TREE_TYPE (TREE_OPERAND (expr, 0));
3400 
3401 	if (POINTER_TYPE_P (totype)
3402 	    && !c_inhibit_evaluation_warnings
3403 	    && TREE_CODE (fromtype) == REFERENCE_TYPE)
3404 	  {
3405 	    tree inner = expr;
3406 	    STRIP_NOPS (inner);
3407 
3408 	    if (DECL_P (inner))
3409 	      warning_at (location,
3410 			  OPT_Waddress,
3411 			  "the compiler can assume that the address of "
3412 			  "%qD will always evaluate to %<true%>",
3413 			  inner);
3414 	  }
3415 
3416 	/* Don't cancel the effect of a CONVERT_EXPR from a REFERENCE_TYPE,
3417 	   since that affects how `default_conversion' will behave.  */
3418 	if (TREE_CODE (totype) == REFERENCE_TYPE
3419 	    || TREE_CODE (fromtype) == REFERENCE_TYPE)
3420 	  break;
3421 	/* Don't strip a conversion from C++0x scoped enum, since they
3422 	   don't implicitly convert to other types.  */
3423 	if (TREE_CODE (fromtype) == ENUMERAL_TYPE
3424 	    && ENUM_IS_SCOPED (fromtype))
3425 	  break;
3426 	/* If this isn't narrowing the argument, we can ignore it.  */
3427 	if (TYPE_PRECISION (totype) >= TYPE_PRECISION (fromtype))
3428 	  return c_common_truthvalue_conversion (location,
3429 						 TREE_OPERAND (expr, 0));
3430       }
3431       break;
3432 
3433     case MODIFY_EXPR:
3434       if (!TREE_NO_WARNING (expr)
3435 	  && warn_parentheses)
3436 	{
3437 	  warning_at (location, OPT_Wparentheses,
3438 		      "suggest parentheses around assignment used as "
3439 		      "truth value");
3440 	  TREE_NO_WARNING (expr) = 1;
3441 	}
3442       break;
3443 
3444     default:
3445       break;
3446     }
3447 
3448   if (TREE_CODE (TREE_TYPE (expr)) == COMPLEX_TYPE)
3449     {
3450       tree t = save_expr (expr);
3451       expr = (build_binary_op
3452 	      (EXPR_LOCATION (expr),
3453 	       (TREE_SIDE_EFFECTS (expr)
3454 		? TRUTH_OR_EXPR : TRUTH_ORIF_EXPR),
3455 	c_common_truthvalue_conversion
3456 	       (location,
3457 		build_unary_op (location, REALPART_EXPR, t, false)),
3458 	c_common_truthvalue_conversion
3459 	       (location,
3460 		build_unary_op (location, IMAGPART_EXPR, t, false)),
3461 	       false));
3462       goto ret;
3463     }
3464 
3465   if (TREE_CODE (TREE_TYPE (expr)) == FIXED_POINT_TYPE)
3466     {
3467       tree fixed_zero_node = build_fixed (TREE_TYPE (expr),
3468 					  FCONST0 (TYPE_MODE
3469 						   (TREE_TYPE (expr))));
3470       return build_binary_op (location, NE_EXPR, expr, fixed_zero_node, true);
3471     }
3472   else
3473     return build_binary_op (location, NE_EXPR, expr, integer_zero_node, true);
3474 
3475  ret:
3476   protected_set_expr_location (expr, location);
3477   return expr;
3478 }
3479 
3480 static void def_builtin_1  (enum built_in_function fncode,
3481 			    const char *name,
3482 			    enum built_in_class fnclass,
3483 			    tree fntype, tree libtype,
3484 			    bool both_p, bool fallback_p, bool nonansi_p,
3485 			    tree fnattrs, bool implicit_p);
3486 
3487 
3488 /* Apply the TYPE_QUALS to the new DECL.  */
3489 
3490 void
3491 c_apply_type_quals_to_decl (int type_quals, tree decl)
3492 {
3493   tree type = TREE_TYPE (decl);
3494 
3495   if (type == error_mark_node)
3496     return;
3497 
3498   if ((type_quals & TYPE_QUAL_CONST)
3499       || (type && TREE_CODE (type) == REFERENCE_TYPE))
3500     /* We used to check TYPE_NEEDS_CONSTRUCTING here, but now a constexpr
3501        constructor can produce constant init, so rely on cp_finish_decl to
3502        clear TREE_READONLY if the variable has non-constant init.  */
3503     TREE_READONLY (decl) = 1;
3504   if (type_quals & TYPE_QUAL_VOLATILE)
3505     {
3506       TREE_SIDE_EFFECTS (decl) = 1;
3507       TREE_THIS_VOLATILE (decl) = 1;
3508     }
3509   if (type_quals & TYPE_QUAL_RESTRICT)
3510     {
3511       while (type && TREE_CODE (type) == ARRAY_TYPE)
3512 	/* Allow 'restrict' on arrays of pointers.
3513 	   FIXME currently we just ignore it.  */
3514 	type = TREE_TYPE (type);
3515       if (!type
3516 	  || !POINTER_TYPE_P (type)
3517 	  || !C_TYPE_OBJECT_OR_INCOMPLETE_P (TREE_TYPE (type)))
3518 	error ("invalid use of %<restrict%>");
3519     }
3520 }
3521 
3522 /* Return the typed-based alias set for T, which may be an expression
3523    or a type.  Return -1 if we don't do anything special.  */
3524 
3525 alias_set_type
3526 c_common_get_alias_set (tree t)
3527 {
3528   /* For VLAs, use the alias set of the element type rather than the
3529      default of alias set 0 for types compared structurally.  */
3530   if (TYPE_P (t) && TYPE_STRUCTURAL_EQUALITY_P (t))
3531     {
3532       if (TREE_CODE (t) == ARRAY_TYPE)
3533 	return get_alias_set (TREE_TYPE (t));
3534       return -1;
3535     }
3536 
3537   /* That's all the expressions we handle specially.  */
3538   if (!TYPE_P (t))
3539     return -1;
3540 
3541   /* The C standard guarantees that any object may be accessed via an
3542      lvalue that has character type.  */
3543   if (t == char_type_node
3544       || t == signed_char_type_node
3545       || t == unsigned_char_type_node)
3546     return 0;
3547 
3548   /* The C standard specifically allows aliasing between signed and
3549      unsigned variants of the same type.  We treat the signed
3550      variant as canonical.  */
3551   if (TREE_CODE (t) == INTEGER_TYPE && TYPE_UNSIGNED (t))
3552     {
3553       tree t1 = c_common_signed_type (t);
3554 
3555       /* t1 == t can happen for boolean nodes which are always unsigned.  */
3556       if (t1 != t)
3557 	return get_alias_set (t1);
3558     }
3559 
3560   return -1;
3561 }
3562 
3563 /* Compute the value of 'sizeof (TYPE)' or '__alignof__ (TYPE)', where
3564    the IS_SIZEOF parameter indicates which operator is being applied.
3565    The COMPLAIN flag controls whether we should diagnose possibly
3566    ill-formed constructs or not.  LOC is the location of the SIZEOF or
3567    TYPEOF operator.  If MIN_ALIGNOF, the least alignment required for
3568    a type in any context should be returned, rather than the normal
3569    alignment for that type.  */
3570 
3571 tree
3572 c_sizeof_or_alignof_type (location_t loc,
3573 			  tree type, bool is_sizeof, bool min_alignof,
3574 			  int complain)
3575 {
3576   const char *op_name;
3577   tree value = NULL;
3578   enum tree_code type_code = TREE_CODE (type);
3579 
3580   op_name = is_sizeof ? "sizeof" : "__alignof__";
3581 
3582   if (type_code == FUNCTION_TYPE)
3583     {
3584       if (is_sizeof)
3585 	{
3586 	  if (complain && warn_pointer_arith)
3587 	    pedwarn (loc, OPT_Wpointer_arith,
3588 		     "invalid application of %<sizeof%> to a function type");
3589           else if (!complain)
3590             return error_mark_node;
3591 	  value = size_one_node;
3592 	}
3593       else
3594 	{
3595 	  if (complain)
3596 	    {
3597 	      if (c_dialect_cxx ())
3598 		pedwarn (loc, OPT_Wpedantic, "ISO C++ does not permit "
3599 			 "%<alignof%> applied to a function type");
3600 	      else
3601 		pedwarn (loc, OPT_Wpedantic, "ISO C does not permit "
3602 			 "%<_Alignof%> applied to a function type");
3603 	    }
3604 	  value = size_int (FUNCTION_BOUNDARY / BITS_PER_UNIT);
3605 	}
3606     }
3607   else if (type_code == VOID_TYPE || type_code == ERROR_MARK)
3608     {
3609       if (type_code == VOID_TYPE
3610 	  && complain && warn_pointer_arith)
3611 	pedwarn (loc, OPT_Wpointer_arith,
3612 		 "invalid application of %qs to a void type", op_name);
3613       else if (!complain)
3614         return error_mark_node;
3615       value = size_one_node;
3616     }
3617   else if (!COMPLETE_TYPE_P (type)
3618 	   && (!c_dialect_cxx () || is_sizeof || type_code != ARRAY_TYPE))
3619     {
3620       if (complain)
3621 	error_at (loc, "invalid application of %qs to incomplete type %qT",
3622 		  op_name, type);
3623       return error_mark_node;
3624     }
3625   else if (c_dialect_cxx () && type_code == ARRAY_TYPE
3626 	   && !COMPLETE_TYPE_P (TREE_TYPE (type)))
3627     {
3628       if (complain)
3629 	error_at (loc, "invalid application of %qs to array type %qT of "
3630 		  "incomplete element type", op_name, type);
3631       return error_mark_node;
3632     }
3633   else
3634     {
3635       if (is_sizeof)
3636 	/* Convert in case a char is more than one unit.  */
3637 	value = size_binop_loc (loc, CEIL_DIV_EXPR, TYPE_SIZE_UNIT (type),
3638 				size_int (TYPE_PRECISION (char_type_node)
3639 					  / BITS_PER_UNIT));
3640       else if (min_alignof)
3641 	value = size_int (min_align_of_type (type));
3642       else
3643 	value = size_int (TYPE_ALIGN_UNIT (type));
3644     }
3645 
3646   /* VALUE will have the middle-end integer type sizetype.
3647      However, we should really return a value of type `size_t',
3648      which is just a typedef for an ordinary integer type.  */
3649   value = fold_convert_loc (loc, size_type_node, value);
3650 
3651   return value;
3652 }
3653 
3654 /* Implement the __alignof keyword: Return the minimum required
3655    alignment of EXPR, measured in bytes.  For VAR_DECLs,
3656    FUNCTION_DECLs and FIELD_DECLs return DECL_ALIGN (which can be set
3657    from an "aligned" __attribute__ specification).  LOC is the
3658    location of the ALIGNOF operator.  */
3659 
3660 tree
3661 c_alignof_expr (location_t loc, tree expr)
3662 {
3663   tree t;
3664 
3665   if (VAR_OR_FUNCTION_DECL_P (expr))
3666     t = size_int (DECL_ALIGN_UNIT (expr));
3667 
3668   else if (TREE_CODE (expr) == COMPONENT_REF
3669 	   && DECL_C_BIT_FIELD (TREE_OPERAND (expr, 1)))
3670     {
3671       error_at (loc, "%<__alignof%> applied to a bit-field");
3672       t = size_one_node;
3673     }
3674   else if (TREE_CODE (expr) == COMPONENT_REF
3675 	   && TREE_CODE (TREE_OPERAND (expr, 1)) == FIELD_DECL)
3676     t = size_int (DECL_ALIGN_UNIT (TREE_OPERAND (expr, 1)));
3677 
3678   else if (INDIRECT_REF_P (expr))
3679     {
3680       tree t = TREE_OPERAND (expr, 0);
3681       tree best = t;
3682       int bestalign = TYPE_ALIGN (TREE_TYPE (TREE_TYPE (t)));
3683 
3684       while (CONVERT_EXPR_P (t)
3685 	     && TREE_CODE (TREE_TYPE (TREE_OPERAND (t, 0))) == POINTER_TYPE)
3686 	{
3687 	  int thisalign;
3688 
3689 	  t = TREE_OPERAND (t, 0);
3690 	  thisalign = TYPE_ALIGN (TREE_TYPE (TREE_TYPE (t)));
3691 	  if (thisalign > bestalign)
3692 	    best = t, bestalign = thisalign;
3693 	}
3694       return c_alignof (loc, TREE_TYPE (TREE_TYPE (best)));
3695     }
3696   else
3697     return c_alignof (loc, TREE_TYPE (expr));
3698 
3699   return fold_convert_loc (loc, size_type_node, t);
3700 }
3701 
3702 /* Handle C and C++ default attributes.  */
3703 
3704 enum built_in_attribute
3705 {
3706 #define DEF_ATTR_NULL_TREE(ENUM) ENUM,
3707 #define DEF_ATTR_INT(ENUM, VALUE) ENUM,
3708 #define DEF_ATTR_STRING(ENUM, VALUE) ENUM,
3709 #define DEF_ATTR_IDENT(ENUM, STRING) ENUM,
3710 #define DEF_ATTR_TREE_LIST(ENUM, PURPOSE, VALUE, CHAIN) ENUM,
3711 #include "builtin-attrs.def"
3712 #undef DEF_ATTR_NULL_TREE
3713 #undef DEF_ATTR_INT
3714 #undef DEF_ATTR_STRING
3715 #undef DEF_ATTR_IDENT
3716 #undef DEF_ATTR_TREE_LIST
3717   ATTR_LAST
3718 };
3719 
3720 static GTY(()) tree built_in_attributes[(int) ATTR_LAST];
3721 
3722 static void c_init_attributes (void);
3723 
3724 enum c_builtin_type
3725 {
3726 #define DEF_PRIMITIVE_TYPE(NAME, VALUE) NAME,
3727 #define DEF_FUNCTION_TYPE_0(NAME, RETURN) NAME,
3728 #define DEF_FUNCTION_TYPE_1(NAME, RETURN, ARG1) NAME,
3729 #define DEF_FUNCTION_TYPE_2(NAME, RETURN, ARG1, ARG2) NAME,
3730 #define DEF_FUNCTION_TYPE_3(NAME, RETURN, ARG1, ARG2, ARG3) NAME,
3731 #define DEF_FUNCTION_TYPE_4(NAME, RETURN, ARG1, ARG2, ARG3, ARG4) NAME,
3732 #define DEF_FUNCTION_TYPE_5(NAME, RETURN, ARG1, ARG2, ARG3, ARG4, ARG5) NAME,
3733 #define DEF_FUNCTION_TYPE_6(NAME, RETURN, ARG1, ARG2, ARG3, ARG4, ARG5, \
3734 			    ARG6) NAME,
3735 #define DEF_FUNCTION_TYPE_7(NAME, RETURN, ARG1, ARG2, ARG3, ARG4, ARG5, \
3736 			    ARG6, ARG7) NAME,
3737 #define DEF_FUNCTION_TYPE_8(NAME, RETURN, ARG1, ARG2, ARG3, ARG4, ARG5, \
3738 			    ARG6, ARG7, ARG8) NAME,
3739 #define DEF_FUNCTION_TYPE_9(NAME, RETURN, ARG1, ARG2, ARG3, ARG4, ARG5, \
3740 			    ARG6, ARG7, ARG8, ARG9) NAME,
3741 #define DEF_FUNCTION_TYPE_10(NAME, RETURN, ARG1, ARG2, ARG3, ARG4, ARG5, \
3742 			     ARG6, ARG7, ARG8, ARG9, ARG10) NAME,
3743 #define DEF_FUNCTION_TYPE_11(NAME, RETURN, ARG1, ARG2, ARG3, ARG4, ARG5, \
3744 			     ARG6, ARG7, ARG8, ARG9, ARG10, ARG11) NAME,
3745 #define DEF_FUNCTION_TYPE_VAR_0(NAME, RETURN) NAME,
3746 #define DEF_FUNCTION_TYPE_VAR_1(NAME, RETURN, ARG1) NAME,
3747 #define DEF_FUNCTION_TYPE_VAR_2(NAME, RETURN, ARG1, ARG2) NAME,
3748 #define DEF_FUNCTION_TYPE_VAR_3(NAME, RETURN, ARG1, ARG2, ARG3) NAME,
3749 #define DEF_FUNCTION_TYPE_VAR_4(NAME, RETURN, ARG1, ARG2, ARG3, ARG4) NAME,
3750 #define DEF_FUNCTION_TYPE_VAR_5(NAME, RETURN, ARG1, ARG2, ARG3, ARG4, ARG5) \
3751 				NAME,
3752 #define DEF_FUNCTION_TYPE_VAR_6(NAME, RETURN, ARG1, ARG2, ARG3, ARG4, ARG5, \
3753 				ARG6) NAME,
3754 #define DEF_FUNCTION_TYPE_VAR_7(NAME, RETURN, ARG1, ARG2, ARG3, ARG4, ARG5, \
3755 				ARG6, ARG7) NAME,
3756 #define DEF_POINTER_TYPE(NAME, TYPE) NAME,
3757 #include "builtin-types.def"
3758 #undef DEF_PRIMITIVE_TYPE
3759 #undef DEF_FUNCTION_TYPE_0
3760 #undef DEF_FUNCTION_TYPE_1
3761 #undef DEF_FUNCTION_TYPE_2
3762 #undef DEF_FUNCTION_TYPE_3
3763 #undef DEF_FUNCTION_TYPE_4
3764 #undef DEF_FUNCTION_TYPE_5
3765 #undef DEF_FUNCTION_TYPE_6
3766 #undef DEF_FUNCTION_TYPE_7
3767 #undef DEF_FUNCTION_TYPE_8
3768 #undef DEF_FUNCTION_TYPE_9
3769 #undef DEF_FUNCTION_TYPE_10
3770 #undef DEF_FUNCTION_TYPE_11
3771 #undef DEF_FUNCTION_TYPE_VAR_0
3772 #undef DEF_FUNCTION_TYPE_VAR_1
3773 #undef DEF_FUNCTION_TYPE_VAR_2
3774 #undef DEF_FUNCTION_TYPE_VAR_3
3775 #undef DEF_FUNCTION_TYPE_VAR_4
3776 #undef DEF_FUNCTION_TYPE_VAR_5
3777 #undef DEF_FUNCTION_TYPE_VAR_6
3778 #undef DEF_FUNCTION_TYPE_VAR_7
3779 #undef DEF_POINTER_TYPE
3780   BT_LAST
3781 };
3782 
3783 typedef enum c_builtin_type builtin_type;
3784 
3785 /* A temporary array for c_common_nodes_and_builtins.  Used in
3786    communication with def_fn_type.  */
3787 static tree builtin_types[(int) BT_LAST + 1];
3788 
3789 /* A helper function for c_common_nodes_and_builtins.  Build function type
3790    for DEF with return type RET and N arguments.  If VAR is true, then the
3791    function should be variadic after those N arguments.
3792 
3793    Takes special care not to ICE if any of the types involved are
3794    error_mark_node, which indicates that said type is not in fact available
3795    (see builtin_type_for_size).  In which case the function type as a whole
3796    should be error_mark_node.  */
3797 
3798 static void
3799 def_fn_type (builtin_type def, builtin_type ret, bool var, int n, ...)
3800 {
3801   tree t;
3802   tree *args = XALLOCAVEC (tree, n);
3803   va_list list;
3804   int i;
3805 
3806   va_start (list, n);
3807   for (i = 0; i < n; ++i)
3808     {
3809       builtin_type a = (builtin_type) va_arg (list, int);
3810       t = builtin_types[a];
3811       if (t == error_mark_node)
3812 	goto egress;
3813       args[i] = t;
3814     }
3815 
3816   t = builtin_types[ret];
3817   if (t == error_mark_node)
3818     goto egress;
3819   if (var)
3820     t = build_varargs_function_type_array (t, n, args);
3821   else
3822     t = build_function_type_array (t, n, args);
3823 
3824  egress:
3825   builtin_types[def] = t;
3826   va_end (list);
3827 }
3828 
3829 /* Build builtin functions common to both C and C++ language
3830    frontends.  */
3831 
3832 static void
3833 c_define_builtins (tree va_list_ref_type_node, tree va_list_arg_type_node)
3834 {
3835 #define DEF_PRIMITIVE_TYPE(ENUM, VALUE) \
3836   builtin_types[ENUM] = VALUE;
3837 #define DEF_FUNCTION_TYPE_0(ENUM, RETURN) \
3838   def_fn_type (ENUM, RETURN, 0, 0);
3839 #define DEF_FUNCTION_TYPE_1(ENUM, RETURN, ARG1) \
3840   def_fn_type (ENUM, RETURN, 0, 1, ARG1);
3841 #define DEF_FUNCTION_TYPE_2(ENUM, RETURN, ARG1, ARG2) \
3842   def_fn_type (ENUM, RETURN, 0, 2, ARG1, ARG2);
3843 #define DEF_FUNCTION_TYPE_3(ENUM, RETURN, ARG1, ARG2, ARG3) \
3844   def_fn_type (ENUM, RETURN, 0, 3, ARG1, ARG2, ARG3);
3845 #define DEF_FUNCTION_TYPE_4(ENUM, RETURN, ARG1, ARG2, ARG3, ARG4) \
3846   def_fn_type (ENUM, RETURN, 0, 4, ARG1, ARG2, ARG3, ARG4);
3847 #define DEF_FUNCTION_TYPE_5(ENUM, RETURN, ARG1, ARG2, ARG3, ARG4, ARG5)	\
3848   def_fn_type (ENUM, RETURN, 0, 5, ARG1, ARG2, ARG3, ARG4, ARG5);
3849 #define DEF_FUNCTION_TYPE_6(ENUM, RETURN, ARG1, ARG2, ARG3, ARG4, ARG5, \
3850 			    ARG6)					\
3851   def_fn_type (ENUM, RETURN, 0, 6, ARG1, ARG2, ARG3, ARG4, ARG5, ARG6);
3852 #define DEF_FUNCTION_TYPE_7(ENUM, RETURN, ARG1, ARG2, ARG3, ARG4, ARG5, \
3853 			    ARG6, ARG7)					\
3854   def_fn_type (ENUM, RETURN, 0, 7, ARG1, ARG2, ARG3, ARG4, ARG5, ARG6, ARG7);
3855 #define DEF_FUNCTION_TYPE_8(ENUM, RETURN, ARG1, ARG2, ARG3, ARG4, ARG5, \
3856 			    ARG6, ARG7, ARG8)				\
3857   def_fn_type (ENUM, RETURN, 0, 8, ARG1, ARG2, ARG3, ARG4, ARG5, ARG6,	\
3858 	       ARG7, ARG8);
3859 #define DEF_FUNCTION_TYPE_9(ENUM, RETURN, ARG1, ARG2, ARG3, ARG4, ARG5, \
3860 			    ARG6, ARG7, ARG8, ARG9)			\
3861   def_fn_type (ENUM, RETURN, 0, 9, ARG1, ARG2, ARG3, ARG4, ARG5, ARG6,	\
3862 	       ARG7, ARG8, ARG9);
3863 #define DEF_FUNCTION_TYPE_10(ENUM, RETURN, ARG1, ARG2, ARG3, ARG4, ARG5, \
3864 			     ARG6, ARG7, ARG8, ARG9, ARG10)		 \
3865   def_fn_type (ENUM, RETURN, 0, 10, ARG1, ARG2, ARG3, ARG4, ARG5, ARG6,	 \
3866 	       ARG7, ARG8, ARG9, ARG10);
3867 #define DEF_FUNCTION_TYPE_11(ENUM, RETURN, ARG1, ARG2, ARG3, ARG4, ARG5, \
3868 			     ARG6, ARG7, ARG8, ARG9, ARG10, ARG11)	 \
3869   def_fn_type (ENUM, RETURN, 0, 11, ARG1, ARG2, ARG3, ARG4, ARG5, ARG6,	 \
3870 	       ARG7, ARG8, ARG9, ARG10, ARG11);
3871 #define DEF_FUNCTION_TYPE_VAR_0(ENUM, RETURN) \
3872   def_fn_type (ENUM, RETURN, 1, 0);
3873 #define DEF_FUNCTION_TYPE_VAR_1(ENUM, RETURN, ARG1) \
3874   def_fn_type (ENUM, RETURN, 1, 1, ARG1);
3875 #define DEF_FUNCTION_TYPE_VAR_2(ENUM, RETURN, ARG1, ARG2) \
3876   def_fn_type (ENUM, RETURN, 1, 2, ARG1, ARG2);
3877 #define DEF_FUNCTION_TYPE_VAR_3(ENUM, RETURN, ARG1, ARG2, ARG3) \
3878   def_fn_type (ENUM, RETURN, 1, 3, ARG1, ARG2, ARG3);
3879 #define DEF_FUNCTION_TYPE_VAR_4(ENUM, RETURN, ARG1, ARG2, ARG3, ARG4) \
3880   def_fn_type (ENUM, RETURN, 1, 4, ARG1, ARG2, ARG3, ARG4);
3881 #define DEF_FUNCTION_TYPE_VAR_5(ENUM, RETURN, ARG1, ARG2, ARG3, ARG4, ARG5) \
3882   def_fn_type (ENUM, RETURN, 1, 5, ARG1, ARG2, ARG3, ARG4, ARG5);
3883 #define DEF_FUNCTION_TYPE_VAR_6(ENUM, RETURN, ARG1, ARG2, ARG3, ARG4, ARG5, \
3884 				ARG6) \
3885   def_fn_type (ENUM, RETURN, 1, 6, ARG1, ARG2, ARG3, ARG4, ARG5, ARG6);
3886 #define DEF_FUNCTION_TYPE_VAR_7(ENUM, RETURN, ARG1, ARG2, ARG3, ARG4, ARG5, \
3887 				ARG6, ARG7)				\
3888   def_fn_type (ENUM, RETURN, 1, 7, ARG1, ARG2, ARG3, ARG4, ARG5, ARG6, ARG7);
3889 #define DEF_POINTER_TYPE(ENUM, TYPE) \
3890   builtin_types[(int) ENUM] = build_pointer_type (builtin_types[(int) TYPE]);
3891 
3892 #include "builtin-types.def"
3893 
3894 #undef DEF_PRIMITIVE_TYPE
3895 #undef DEF_FUNCTION_TYPE_0
3896 #undef DEF_FUNCTION_TYPE_1
3897 #undef DEF_FUNCTION_TYPE_2
3898 #undef DEF_FUNCTION_TYPE_3
3899 #undef DEF_FUNCTION_TYPE_4
3900 #undef DEF_FUNCTION_TYPE_5
3901 #undef DEF_FUNCTION_TYPE_6
3902 #undef DEF_FUNCTION_TYPE_7
3903 #undef DEF_FUNCTION_TYPE_8
3904 #undef DEF_FUNCTION_TYPE_9
3905 #undef DEF_FUNCTION_TYPE_10
3906 #undef DEF_FUNCTION_TYPE_11
3907 #undef DEF_FUNCTION_TYPE_VAR_0
3908 #undef DEF_FUNCTION_TYPE_VAR_1
3909 #undef DEF_FUNCTION_TYPE_VAR_2
3910 #undef DEF_FUNCTION_TYPE_VAR_3
3911 #undef DEF_FUNCTION_TYPE_VAR_4
3912 #undef DEF_FUNCTION_TYPE_VAR_5
3913 #undef DEF_FUNCTION_TYPE_VAR_6
3914 #undef DEF_FUNCTION_TYPE_VAR_7
3915 #undef DEF_POINTER_TYPE
3916   builtin_types[(int) BT_LAST] = NULL_TREE;
3917 
3918   c_init_attributes ();
3919 
3920 #define DEF_BUILTIN(ENUM, NAME, CLASS, TYPE, LIBTYPE, BOTH_P, FALLBACK_P, \
3921 		    NONANSI_P, ATTRS, IMPLICIT, COND)			\
3922   if (NAME && COND)							\
3923     def_builtin_1 (ENUM, NAME, CLASS,                                   \
3924 		   builtin_types[(int) TYPE],                           \
3925 		   builtin_types[(int) LIBTYPE],                        \
3926 		   BOTH_P, FALLBACK_P, NONANSI_P,                       \
3927 		   built_in_attributes[(int) ATTRS], IMPLICIT);
3928 #include "builtins.def"
3929 
3930   targetm.init_builtins ();
3931 
3932   build_common_builtin_nodes ();
3933 }
3934 
3935 /* Like get_identifier, but avoid warnings about null arguments when
3936    the argument may be NULL for targets where GCC lacks stdint.h type
3937    information.  */
3938 
3939 static inline tree
3940 c_get_ident (const char *id)
3941 {
3942   return get_identifier (id);
3943 }
3944 
3945 /* Build tree nodes and builtin functions common to both C and C++ language
3946    frontends.  */
3947 
3948 void
3949 c_common_nodes_and_builtins (void)
3950 {
3951   int char16_type_size;
3952   int char32_type_size;
3953   int wchar_type_size;
3954   tree array_domain_type;
3955   tree va_list_ref_type_node;
3956   tree va_list_arg_type_node;
3957   int i;
3958 
3959   build_common_tree_nodes (flag_signed_char);
3960 
3961   /* Define `int' and `char' first so that dbx will output them first.  */
3962   record_builtin_type (RID_INT, NULL, integer_type_node);
3963   record_builtin_type (RID_CHAR, "char", char_type_node);
3964 
3965   /* `signed' is the same as `int'.  FIXME: the declarations of "signed",
3966      "unsigned long", "long long unsigned" and "unsigned short" were in C++
3967      but not C.  Are the conditionals here needed?  */
3968   if (c_dialect_cxx ())
3969     record_builtin_type (RID_SIGNED, NULL, integer_type_node);
3970   record_builtin_type (RID_LONG, "long int", long_integer_type_node);
3971   record_builtin_type (RID_UNSIGNED, "unsigned int", unsigned_type_node);
3972   record_builtin_type (RID_MAX, "long unsigned int",
3973 		       long_unsigned_type_node);
3974 
3975   for (i = 0; i < NUM_INT_N_ENTS; i ++)
3976     {
3977       char name[25];
3978 
3979       sprintf (name, "__int%d", int_n_data[i].bitsize);
3980       record_builtin_type ((enum rid)(RID_FIRST_INT_N + i), name,
3981 			   int_n_trees[i].signed_type);
3982       sprintf (name, "__int%d unsigned", int_n_data[i].bitsize);
3983       record_builtin_type (RID_MAX, name, int_n_trees[i].unsigned_type);
3984     }
3985 
3986   if (c_dialect_cxx ())
3987     record_builtin_type (RID_MAX, "unsigned long", long_unsigned_type_node);
3988   record_builtin_type (RID_MAX, "long long int",
3989 		       long_long_integer_type_node);
3990   record_builtin_type (RID_MAX, "long long unsigned int",
3991 		       long_long_unsigned_type_node);
3992   if (c_dialect_cxx ())
3993     record_builtin_type (RID_MAX, "long long unsigned",
3994 			 long_long_unsigned_type_node);
3995   record_builtin_type (RID_SHORT, "short int", short_integer_type_node);
3996   record_builtin_type (RID_MAX, "short unsigned int",
3997 		       short_unsigned_type_node);
3998   if (c_dialect_cxx ())
3999     record_builtin_type (RID_MAX, "unsigned short",
4000 			 short_unsigned_type_node);
4001 
4002   /* Define both `signed char' and `unsigned char'.  */
4003   record_builtin_type (RID_MAX, "signed char", signed_char_type_node);
4004   record_builtin_type (RID_MAX, "unsigned char", unsigned_char_type_node);
4005 
4006   /* These are types that c_common_type_for_size and
4007      c_common_type_for_mode use.  */
4008   lang_hooks.decls.pushdecl (build_decl (UNKNOWN_LOCATION,
4009 					 TYPE_DECL, NULL_TREE,
4010 					 intQI_type_node));
4011   lang_hooks.decls.pushdecl (build_decl (UNKNOWN_LOCATION,
4012 					 TYPE_DECL, NULL_TREE,
4013 					 intHI_type_node));
4014   lang_hooks.decls.pushdecl (build_decl (UNKNOWN_LOCATION,
4015 					 TYPE_DECL, NULL_TREE,
4016 					 intSI_type_node));
4017   lang_hooks.decls.pushdecl (build_decl (UNKNOWN_LOCATION,
4018 					 TYPE_DECL, NULL_TREE,
4019 					 intDI_type_node));
4020 #if HOST_BITS_PER_WIDE_INT >= 64
4021   /* Note that this is different than the __int128 type that's part of
4022      the generic __intN support.  */
4023   if (targetm.scalar_mode_supported_p (TImode))
4024     lang_hooks.decls.pushdecl (build_decl (UNKNOWN_LOCATION,
4025 					   TYPE_DECL,
4026 					   get_identifier ("__int128_t"),
4027 					   intTI_type_node));
4028 #endif
4029   lang_hooks.decls.pushdecl (build_decl (UNKNOWN_LOCATION,
4030 					 TYPE_DECL, NULL_TREE,
4031 					 unsigned_intQI_type_node));
4032   lang_hooks.decls.pushdecl (build_decl (UNKNOWN_LOCATION,
4033 					 TYPE_DECL, NULL_TREE,
4034 					 unsigned_intHI_type_node));
4035   lang_hooks.decls.pushdecl (build_decl (UNKNOWN_LOCATION,
4036 					 TYPE_DECL, NULL_TREE,
4037 					 unsigned_intSI_type_node));
4038   lang_hooks.decls.pushdecl (build_decl (UNKNOWN_LOCATION,
4039 					 TYPE_DECL, NULL_TREE,
4040 					 unsigned_intDI_type_node));
4041 #if HOST_BITS_PER_WIDE_INT >= 64
4042   if (targetm.scalar_mode_supported_p (TImode))
4043     lang_hooks.decls.pushdecl (build_decl (UNKNOWN_LOCATION,
4044 					   TYPE_DECL,
4045 					   get_identifier ("__uint128_t"),
4046 					   unsigned_intTI_type_node));
4047 #endif
4048 
4049   /* Create the widest literal types.  */
4050   if (targetm.scalar_mode_supported_p (TImode))
4051     {
4052       widest_integer_literal_type_node = intTI_type_node;
4053       widest_unsigned_literal_type_node = unsigned_intTI_type_node;
4054     }
4055   else
4056     {
4057       widest_integer_literal_type_node = intDI_type_node;
4058       widest_unsigned_literal_type_node = unsigned_intDI_type_node;
4059     }
4060 
4061   signed_size_type_node = c_common_signed_type (size_type_node);
4062 
4063   pid_type_node =
4064     TREE_TYPE (identifier_global_value (get_identifier (PID_TYPE)));
4065 
4066   record_builtin_type (RID_FLOAT, NULL, float_type_node);
4067   record_builtin_type (RID_DOUBLE, NULL, double_type_node);
4068   record_builtin_type (RID_MAX, "long double", long_double_type_node);
4069 
4070   if (!c_dialect_cxx ())
4071     for (i = 0; i < NUM_FLOATN_NX_TYPES; i++)
4072       if (FLOATN_NX_TYPE_NODE (i) != NULL_TREE)
4073 	record_builtin_type ((enum rid) (RID_FLOATN_NX_FIRST + i), NULL,
4074 			     FLOATN_NX_TYPE_NODE (i));
4075 
4076   /* Only supported decimal floating point extension if the target
4077      actually supports underlying modes. */
4078   if (targetm.scalar_mode_supported_p (SDmode)
4079       && targetm.scalar_mode_supported_p (DDmode)
4080       && targetm.scalar_mode_supported_p (TDmode))
4081     {
4082       record_builtin_type (RID_DFLOAT32, NULL, dfloat32_type_node);
4083       record_builtin_type (RID_DFLOAT64, NULL, dfloat64_type_node);
4084       record_builtin_type (RID_DFLOAT128, NULL, dfloat128_type_node);
4085     }
4086 
4087   if (targetm.fixed_point_supported_p ())
4088     {
4089       record_builtin_type (RID_MAX, "short _Fract", short_fract_type_node);
4090       record_builtin_type (RID_FRACT, NULL, fract_type_node);
4091       record_builtin_type (RID_MAX, "long _Fract", long_fract_type_node);
4092       record_builtin_type (RID_MAX, "long long _Fract",
4093 			   long_long_fract_type_node);
4094       record_builtin_type (RID_MAX, "unsigned short _Fract",
4095 			   unsigned_short_fract_type_node);
4096       record_builtin_type (RID_MAX, "unsigned _Fract",
4097 			   unsigned_fract_type_node);
4098       record_builtin_type (RID_MAX, "unsigned long _Fract",
4099 			   unsigned_long_fract_type_node);
4100       record_builtin_type (RID_MAX, "unsigned long long _Fract",
4101 			   unsigned_long_long_fract_type_node);
4102       record_builtin_type (RID_MAX, "_Sat short _Fract",
4103 			   sat_short_fract_type_node);
4104       record_builtin_type (RID_MAX, "_Sat _Fract", sat_fract_type_node);
4105       record_builtin_type (RID_MAX, "_Sat long _Fract",
4106 			   sat_long_fract_type_node);
4107       record_builtin_type (RID_MAX, "_Sat long long _Fract",
4108 			   sat_long_long_fract_type_node);
4109       record_builtin_type (RID_MAX, "_Sat unsigned short _Fract",
4110 			   sat_unsigned_short_fract_type_node);
4111       record_builtin_type (RID_MAX, "_Sat unsigned _Fract",
4112 			   sat_unsigned_fract_type_node);
4113       record_builtin_type (RID_MAX, "_Sat unsigned long _Fract",
4114 			   sat_unsigned_long_fract_type_node);
4115       record_builtin_type (RID_MAX, "_Sat unsigned long long _Fract",
4116 			   sat_unsigned_long_long_fract_type_node);
4117       record_builtin_type (RID_MAX, "short _Accum", short_accum_type_node);
4118       record_builtin_type (RID_ACCUM, NULL, accum_type_node);
4119       record_builtin_type (RID_MAX, "long _Accum", long_accum_type_node);
4120       record_builtin_type (RID_MAX, "long long _Accum",
4121 			   long_long_accum_type_node);
4122       record_builtin_type (RID_MAX, "unsigned short _Accum",
4123 			   unsigned_short_accum_type_node);
4124       record_builtin_type (RID_MAX, "unsigned _Accum",
4125 			   unsigned_accum_type_node);
4126       record_builtin_type (RID_MAX, "unsigned long _Accum",
4127 			   unsigned_long_accum_type_node);
4128       record_builtin_type (RID_MAX, "unsigned long long _Accum",
4129 			   unsigned_long_long_accum_type_node);
4130       record_builtin_type (RID_MAX, "_Sat short _Accum",
4131 			   sat_short_accum_type_node);
4132       record_builtin_type (RID_MAX, "_Sat _Accum", sat_accum_type_node);
4133       record_builtin_type (RID_MAX, "_Sat long _Accum",
4134 			   sat_long_accum_type_node);
4135       record_builtin_type (RID_MAX, "_Sat long long _Accum",
4136 			  sat_long_long_accum_type_node);
4137       record_builtin_type (RID_MAX, "_Sat unsigned short _Accum",
4138 			   sat_unsigned_short_accum_type_node);
4139       record_builtin_type (RID_MAX, "_Sat unsigned _Accum",
4140 			   sat_unsigned_accum_type_node);
4141       record_builtin_type (RID_MAX, "_Sat unsigned long _Accum",
4142 			   sat_unsigned_long_accum_type_node);
4143       record_builtin_type (RID_MAX, "_Sat unsigned long long _Accum",
4144 			   sat_unsigned_long_long_accum_type_node);
4145 
4146     }
4147 
4148   lang_hooks.decls.pushdecl (build_decl (UNKNOWN_LOCATION,
4149 					 TYPE_DECL,
4150 					 get_identifier ("complex int"),
4151 					 complex_integer_type_node));
4152   lang_hooks.decls.pushdecl (build_decl (UNKNOWN_LOCATION,
4153 					 TYPE_DECL,
4154 					 get_identifier ("complex float"),
4155 					 complex_float_type_node));
4156   lang_hooks.decls.pushdecl (build_decl (UNKNOWN_LOCATION,
4157 					 TYPE_DECL,
4158 					 get_identifier ("complex double"),
4159 					 complex_double_type_node));
4160   lang_hooks.decls.pushdecl
4161     (build_decl (UNKNOWN_LOCATION,
4162 		 TYPE_DECL, get_identifier ("complex long double"),
4163 		 complex_long_double_type_node));
4164 
4165   if (!c_dialect_cxx ())
4166     for (i = 0; i < NUM_FLOATN_NX_TYPES; i++)
4167       if (COMPLEX_FLOATN_NX_TYPE_NODE (i) != NULL_TREE)
4168 	{
4169 	  char buf[30];
4170 	  sprintf (buf, "complex _Float%d%s", floatn_nx_types[i].n,
4171 		   floatn_nx_types[i].extended ? "x" : "");
4172 	  lang_hooks.decls.pushdecl
4173 	    (build_decl (UNKNOWN_LOCATION,
4174 			 TYPE_DECL,
4175 			 get_identifier (buf),
4176 			 COMPLEX_FLOATN_NX_TYPE_NODE (i)));
4177 	}
4178 
4179   if (c_dialect_cxx ())
4180     {
4181       /* For C++, make fileptr_type_node a distinct void * type until
4182 	 FILE type is defined.  Likewise for const struct tm*.  */
4183       for (unsigned i = 0;
4184 	   i < sizeof (builtin_structptr_types)
4185 	       / sizeof (builtin_structptr_type);
4186 	   ++i)
4187 	builtin_structptr_types[i].node =
4188 	  build_variant_type_copy (builtin_structptr_types[i].base);
4189 
4190     }
4191 
4192   record_builtin_type (RID_VOID, NULL, void_type_node);
4193 
4194   /* Set the TYPE_NAME for any variants that were built before
4195      record_builtin_type gave names to the built-in types. */
4196   {
4197     tree void_name = TYPE_NAME (void_type_node);
4198     TYPE_NAME (void_type_node) = NULL_TREE;
4199     TYPE_NAME (build_qualified_type (void_type_node, TYPE_QUAL_CONST))
4200       = void_name;
4201     TYPE_NAME (void_type_node) = void_name;
4202   }
4203 
4204   void_list_node = build_void_list_node ();
4205 
4206   /* Make a type to be the domain of a few array types
4207      whose domains don't really matter.
4208      200 is small enough that it always fits in size_t
4209      and large enough that it can hold most function names for the
4210      initializations of __FUNCTION__ and __PRETTY_FUNCTION__.  */
4211   array_domain_type = build_index_type (size_int (200));
4212 
4213   /* Make a type for arrays of characters.
4214      With luck nothing will ever really depend on the length of this
4215      array type.  */
4216   char_array_type_node
4217     = build_array_type (char_type_node, array_domain_type);
4218 
4219   string_type_node = build_pointer_type (char_type_node);
4220   const_string_type_node
4221     = build_pointer_type (build_qualified_type
4222 			  (char_type_node, TYPE_QUAL_CONST));
4223 
4224   /* This is special for C++ so functions can be overloaded.  */
4225   wchar_type_node = get_identifier (MODIFIED_WCHAR_TYPE);
4226   wchar_type_node = TREE_TYPE (identifier_global_value (wchar_type_node));
4227   wchar_type_size = TYPE_PRECISION (wchar_type_node);
4228   underlying_wchar_type_node = wchar_type_node;
4229   if (c_dialect_cxx ())
4230     {
4231       if (TYPE_UNSIGNED (wchar_type_node))
4232 	wchar_type_node = make_unsigned_type (wchar_type_size);
4233       else
4234 	wchar_type_node = make_signed_type (wchar_type_size);
4235       record_builtin_type (RID_WCHAR, "wchar_t", wchar_type_node);
4236     }
4237 
4238   /* This is for wide string constants.  */
4239   wchar_array_type_node
4240     = build_array_type (wchar_type_node, array_domain_type);
4241 
4242   /* Define 'char16_t'.  */
4243   char16_type_node = get_identifier (CHAR16_TYPE);
4244   char16_type_node = TREE_TYPE (identifier_global_value (char16_type_node));
4245   char16_type_size = TYPE_PRECISION (char16_type_node);
4246   if (c_dialect_cxx ())
4247     {
4248       char16_type_node = make_unsigned_type (char16_type_size);
4249 
4250       if (cxx_dialect >= cxx11)
4251 	record_builtin_type (RID_CHAR16, "char16_t", char16_type_node);
4252     }
4253 
4254   /* This is for UTF-16 string constants.  */
4255   char16_array_type_node
4256     = build_array_type (char16_type_node, array_domain_type);
4257 
4258   /* Define 'char32_t'.  */
4259   char32_type_node = get_identifier (CHAR32_TYPE);
4260   char32_type_node = TREE_TYPE (identifier_global_value (char32_type_node));
4261   char32_type_size = TYPE_PRECISION (char32_type_node);
4262   if (c_dialect_cxx ())
4263     {
4264       char32_type_node = make_unsigned_type (char32_type_size);
4265 
4266       if (cxx_dialect >= cxx11)
4267 	record_builtin_type (RID_CHAR32, "char32_t", char32_type_node);
4268     }
4269 
4270   /* This is for UTF-32 string constants.  */
4271   char32_array_type_node
4272     = build_array_type (char32_type_node, array_domain_type);
4273 
4274   wint_type_node =
4275     TREE_TYPE (identifier_global_value (get_identifier (WINT_TYPE)));
4276 
4277   intmax_type_node =
4278     TREE_TYPE (identifier_global_value (get_identifier (INTMAX_TYPE)));
4279   uintmax_type_node =
4280     TREE_TYPE (identifier_global_value (get_identifier (UINTMAX_TYPE)));
4281 
4282   if (SIG_ATOMIC_TYPE)
4283     sig_atomic_type_node =
4284       TREE_TYPE (identifier_global_value (c_get_ident (SIG_ATOMIC_TYPE)));
4285   if (INT8_TYPE)
4286     int8_type_node =
4287       TREE_TYPE (identifier_global_value (c_get_ident (INT8_TYPE)));
4288   if (INT16_TYPE)
4289     int16_type_node =
4290       TREE_TYPE (identifier_global_value (c_get_ident (INT16_TYPE)));
4291   if (INT32_TYPE)
4292     int32_type_node =
4293       TREE_TYPE (identifier_global_value (c_get_ident (INT32_TYPE)));
4294   if (INT64_TYPE)
4295     int64_type_node =
4296       TREE_TYPE (identifier_global_value (c_get_ident (INT64_TYPE)));
4297   if (UINT8_TYPE)
4298     uint8_type_node =
4299       TREE_TYPE (identifier_global_value (c_get_ident (UINT8_TYPE)));
4300   if (UINT16_TYPE)
4301     c_uint16_type_node = uint16_type_node =
4302       TREE_TYPE (identifier_global_value (c_get_ident (UINT16_TYPE)));
4303   if (UINT32_TYPE)
4304     c_uint32_type_node = uint32_type_node =
4305       TREE_TYPE (identifier_global_value (c_get_ident (UINT32_TYPE)));
4306   if (UINT64_TYPE)
4307     c_uint64_type_node = uint64_type_node =
4308       TREE_TYPE (identifier_global_value (c_get_ident (UINT64_TYPE)));
4309   if (INT_LEAST8_TYPE)
4310     int_least8_type_node =
4311       TREE_TYPE (identifier_global_value (c_get_ident (INT_LEAST8_TYPE)));
4312   if (INT_LEAST16_TYPE)
4313     int_least16_type_node =
4314       TREE_TYPE (identifier_global_value (c_get_ident (INT_LEAST16_TYPE)));
4315   if (INT_LEAST32_TYPE)
4316     int_least32_type_node =
4317       TREE_TYPE (identifier_global_value (c_get_ident (INT_LEAST32_TYPE)));
4318   if (INT_LEAST64_TYPE)
4319     int_least64_type_node =
4320       TREE_TYPE (identifier_global_value (c_get_ident (INT_LEAST64_TYPE)));
4321   if (UINT_LEAST8_TYPE)
4322     uint_least8_type_node =
4323       TREE_TYPE (identifier_global_value (c_get_ident (UINT_LEAST8_TYPE)));
4324   if (UINT_LEAST16_TYPE)
4325     uint_least16_type_node =
4326       TREE_TYPE (identifier_global_value (c_get_ident (UINT_LEAST16_TYPE)));
4327   if (UINT_LEAST32_TYPE)
4328     uint_least32_type_node =
4329       TREE_TYPE (identifier_global_value (c_get_ident (UINT_LEAST32_TYPE)));
4330   if (UINT_LEAST64_TYPE)
4331     uint_least64_type_node =
4332       TREE_TYPE (identifier_global_value (c_get_ident (UINT_LEAST64_TYPE)));
4333   if (INT_FAST8_TYPE)
4334     int_fast8_type_node =
4335       TREE_TYPE (identifier_global_value (c_get_ident (INT_FAST8_TYPE)));
4336   if (INT_FAST16_TYPE)
4337     int_fast16_type_node =
4338       TREE_TYPE (identifier_global_value (c_get_ident (INT_FAST16_TYPE)));
4339   if (INT_FAST32_TYPE)
4340     int_fast32_type_node =
4341       TREE_TYPE (identifier_global_value (c_get_ident (INT_FAST32_TYPE)));
4342   if (INT_FAST64_TYPE)
4343     int_fast64_type_node =
4344       TREE_TYPE (identifier_global_value (c_get_ident (INT_FAST64_TYPE)));
4345   if (UINT_FAST8_TYPE)
4346     uint_fast8_type_node =
4347       TREE_TYPE (identifier_global_value (c_get_ident (UINT_FAST8_TYPE)));
4348   if (UINT_FAST16_TYPE)
4349     uint_fast16_type_node =
4350       TREE_TYPE (identifier_global_value (c_get_ident (UINT_FAST16_TYPE)));
4351   if (UINT_FAST32_TYPE)
4352     uint_fast32_type_node =
4353       TREE_TYPE (identifier_global_value (c_get_ident (UINT_FAST32_TYPE)));
4354   if (UINT_FAST64_TYPE)
4355     uint_fast64_type_node =
4356       TREE_TYPE (identifier_global_value (c_get_ident (UINT_FAST64_TYPE)));
4357   if (INTPTR_TYPE)
4358     intptr_type_node =
4359       TREE_TYPE (identifier_global_value (c_get_ident (INTPTR_TYPE)));
4360   if (UINTPTR_TYPE)
4361     uintptr_type_node =
4362       TREE_TYPE (identifier_global_value (c_get_ident (UINTPTR_TYPE)));
4363 
4364   default_function_type
4365     = build_varargs_function_type_list (integer_type_node, NULL_TREE);
4366   unsigned_ptrdiff_type_node = c_common_unsigned_type (ptrdiff_type_node);
4367 
4368   lang_hooks.decls.pushdecl
4369     (build_decl (UNKNOWN_LOCATION,
4370 		 TYPE_DECL, get_identifier ("__builtin_va_list"),
4371 		 va_list_type_node));
4372   if (targetm.enum_va_list_p)
4373     {
4374       int l;
4375       const char *pname;
4376       tree ptype;
4377 
4378       for (l = 0; targetm.enum_va_list_p (l, &pname, &ptype); ++l)
4379 	{
4380 	  lang_hooks.decls.pushdecl
4381 	    (build_decl (UNKNOWN_LOCATION,
4382 		         TYPE_DECL, get_identifier (pname),
4383 	  	         ptype));
4384 
4385 	}
4386     }
4387 
4388   if (TREE_CODE (va_list_type_node) == ARRAY_TYPE)
4389     {
4390       va_list_arg_type_node = va_list_ref_type_node =
4391 	build_pointer_type (TREE_TYPE (va_list_type_node));
4392     }
4393   else
4394     {
4395       va_list_arg_type_node = va_list_type_node;
4396       va_list_ref_type_node = build_reference_type (va_list_type_node);
4397     }
4398 
4399   if (!flag_preprocess_only)
4400     c_define_builtins (va_list_ref_type_node, va_list_arg_type_node);
4401 
4402   main_identifier_node = get_identifier ("main");
4403 
4404   /* Create the built-in __null node.  It is important that this is
4405      not shared.  */
4406   null_node = make_int_cst (1, 1);
4407   TREE_TYPE (null_node) = c_common_type_for_size (POINTER_SIZE, 0);
4408 
4409   /* Since builtin_types isn't gc'ed, don't export these nodes.  */
4410   memset (builtin_types, 0, sizeof (builtin_types));
4411 }
4412 
4413 /* The number of named compound-literals generated thus far.  */
4414 static GTY(()) int compound_literal_number;
4415 
4416 /* Set DECL_NAME for DECL, a VAR_DECL for a compound-literal.  */
4417 
4418 void
4419 set_compound_literal_name (tree decl)
4420 {
4421   char *name;
4422   ASM_FORMAT_PRIVATE_NAME (name, "__compound_literal",
4423 			   compound_literal_number);
4424   compound_literal_number++;
4425   DECL_NAME (decl) = get_identifier (name);
4426 }
4427 
4428 /* build_va_arg helper function.  Return a VA_ARG_EXPR with location LOC, type
4429    TYPE and operand OP.  */
4430 
4431 static tree
4432 build_va_arg_1 (location_t loc, tree type, tree op)
4433 {
4434   tree expr = build1 (VA_ARG_EXPR, type, op);
4435   SET_EXPR_LOCATION (expr, loc);
4436   return expr;
4437 }
4438 
4439 /* Return a VA_ARG_EXPR corresponding to a source-level expression
4440    va_arg (EXPR, TYPE) at source location LOC.  */
4441 
4442 tree
4443 build_va_arg (location_t loc, tree expr, tree type)
4444 {
4445   tree va_type = TREE_TYPE (expr);
4446   tree canon_va_type = (va_type == error_mark_node
4447 			? error_mark_node
4448 			: targetm.canonical_va_list_type (va_type));
4449 
4450   if (va_type == error_mark_node
4451       || canon_va_type == NULL_TREE)
4452     {
4453       if (canon_va_type == NULL_TREE)
4454 	error_at (loc, "first argument to %<va_arg%> not of type %<va_list%>");
4455 
4456       /* Let's handle things neutrallly, if expr:
4457 	 - has undeclared type, or
4458 	 - is not an va_list type.  */
4459       return build_va_arg_1 (loc, type, error_mark_node);
4460     }
4461 
4462   if (TREE_CODE (canon_va_type) != ARRAY_TYPE)
4463     {
4464       /* Case 1: Not an array type.  */
4465 
4466       /* Take the address, to get '&ap'.  Note that &ap is not a va_list
4467 	 type.  */
4468       mark_addressable (expr);
4469       expr = build1 (ADDR_EXPR, build_pointer_type (TREE_TYPE (expr)), expr);
4470 
4471       return build_va_arg_1 (loc, type, expr);
4472     }
4473 
4474   /* Case 2: Array type.
4475 
4476      Background:
4477 
4478      For contrast, let's start with the simple case (case 1).  If
4479      canon_va_type is not an array type, but say a char *, then when
4480      passing-by-value a va_list, the type of the va_list param decl is
4481      the same as for another va_list decl (all ap's are char *):
4482 
4483      f2_1 (char * ap)
4484        D.1815 = VA_ARG (&ap, 0B, 1);
4485        return D.1815;
4486 
4487      f2 (int i)
4488        char * ap.0;
4489        char * ap;
4490        __builtin_va_start (&ap, 0);
4491        ap.0 = ap;
4492        res = f2_1 (ap.0);
4493        __builtin_va_end (&ap);
4494        D.1812 = res;
4495        return D.1812;
4496 
4497      However, if canon_va_type is ARRAY_TYPE, then when passing-by-value a
4498      va_list the type of the va_list param decl (case 2b, struct * ap) is not
4499      the same as for another va_list decl (case 2a, struct ap[1]).
4500 
4501      f2_1 (struct  * ap)
4502        D.1844 = VA_ARG (ap, 0B, 0);
4503        return D.1844;
4504 
4505      f2 (int i)
4506        struct  ap[1];
4507        __builtin_va_start (&ap, 0);
4508        res = f2_1 (&ap);
4509        __builtin_va_end (&ap);
4510        D.1841 = res;
4511        return D.1841;
4512 
4513      Case 2b is different because:
4514      - on the callee side, the parm decl has declared type va_list, but
4515        grokdeclarator changes the type of the parm decl to a pointer to the
4516        array elem type.
4517      - on the caller side, the pass-by-value uses &ap.
4518 
4519      We unify these two cases (case 2a: va_list is array type,
4520      case 2b: va_list is pointer to array elem type), by adding '&' for the
4521      array type case, such that we have a pointer to array elem in both
4522      cases.  */
4523 
4524   if (TREE_CODE (va_type) == ARRAY_TYPE)
4525     {
4526       /* Case 2a: va_list is array type.  */
4527 
4528       /* Take the address, to get '&ap'.  Make sure it's a pointer to array
4529 	 elem type.  */
4530       mark_addressable (expr);
4531       expr = build1 (ADDR_EXPR, build_pointer_type (TREE_TYPE (canon_va_type)),
4532 		     expr);
4533 
4534       /* Verify that &ap is still recognized as having va_list type.  */
4535       tree canon_expr_type
4536 	= targetm.canonical_va_list_type (TREE_TYPE (expr));
4537       gcc_assert (canon_expr_type != NULL_TREE);
4538     }
4539   else
4540     {
4541       /* Case 2b: va_list is pointer to array elem type.  */
4542       gcc_assert (POINTER_TYPE_P (va_type));
4543 
4544       /* Comparison as in std_canonical_va_list_type.  */
4545       gcc_assert (TYPE_MAIN_VARIANT (TREE_TYPE (va_type))
4546 		  == TYPE_MAIN_VARIANT (TREE_TYPE (canon_va_type)));
4547 
4548       /* Don't take the address.  We've already got '&ap'.  */
4549       ;
4550     }
4551 
4552   return build_va_arg_1 (loc, type, expr);
4553 }
4554 
4555 
4556 /* Linked list of disabled built-in functions.  */
4557 
4558 struct disabled_builtin
4559 {
4560   const char *name;
4561   struct disabled_builtin *next;
4562 };
4563 static disabled_builtin *disabled_builtins = NULL;
4564 
4565 static bool builtin_function_disabled_p (const char *);
4566 
4567 /* Disable a built-in function specified by -fno-builtin-NAME.  If NAME
4568    begins with "__builtin_", give an error.  */
4569 
4570 void
4571 disable_builtin_function (const char *name)
4572 {
4573   if (strncmp (name, "__builtin_", strlen ("__builtin_")) == 0)
4574     error ("cannot disable built-in function %qs", name);
4575   else
4576     {
4577       disabled_builtin *new_disabled_builtin = XNEW (disabled_builtin);
4578       new_disabled_builtin->name = name;
4579       new_disabled_builtin->next = disabled_builtins;
4580       disabled_builtins = new_disabled_builtin;
4581     }
4582 }
4583 
4584 
4585 /* Return true if the built-in function NAME has been disabled, false
4586    otherwise.  */
4587 
4588 static bool
4589 builtin_function_disabled_p (const char *name)
4590 {
4591   disabled_builtin *p;
4592   for (p = disabled_builtins; p != NULL; p = p->next)
4593     {
4594       if (strcmp (name, p->name) == 0)
4595 	return true;
4596     }
4597   return false;
4598 }
4599 
4600 
4601 /* Worker for DEF_BUILTIN.
4602    Possibly define a builtin function with one or two names.
4603    Does not declare a non-__builtin_ function if flag_no_builtin, or if
4604    nonansi_p and flag_no_nonansi_builtin.  */
4605 
4606 static void
4607 def_builtin_1 (enum built_in_function fncode,
4608 	       const char *name,
4609 	       enum built_in_class fnclass,
4610 	       tree fntype, tree libtype,
4611 	       bool both_p, bool fallback_p, bool nonansi_p,
4612 	       tree fnattrs, bool implicit_p)
4613 {
4614   tree decl;
4615   const char *libname;
4616 
4617   if (fntype == error_mark_node)
4618     return;
4619 
4620   gcc_assert ((!both_p && !fallback_p)
4621 	      || !strncmp (name, "__builtin_",
4622 			   strlen ("__builtin_")));
4623 
4624   libname = name + strlen ("__builtin_");
4625   decl = add_builtin_function (name, fntype, fncode, fnclass,
4626 			       (fallback_p ? libname : NULL),
4627 			       fnattrs);
4628 
4629   set_builtin_decl (fncode, decl, implicit_p);
4630 
4631   if (both_p
4632       && !flag_no_builtin && !builtin_function_disabled_p (libname)
4633       && !(nonansi_p && flag_no_nonansi_builtin))
4634     add_builtin_function (libname, libtype, fncode, fnclass,
4635 			  NULL, fnattrs);
4636 }
4637 
4638 /* Nonzero if the type T promotes to int.  This is (nearly) the
4639    integral promotions defined in ISO C99 6.3.1.1/2.  */
4640 
4641 bool
4642 c_promoting_integer_type_p (const_tree t)
4643 {
4644   switch (TREE_CODE (t))
4645     {
4646     case INTEGER_TYPE:
4647       return (TYPE_MAIN_VARIANT (t) == char_type_node
4648 	      || TYPE_MAIN_VARIANT (t) == signed_char_type_node
4649 	      || TYPE_MAIN_VARIANT (t) == unsigned_char_type_node
4650 	      || TYPE_MAIN_VARIANT (t) == short_integer_type_node
4651 	      || TYPE_MAIN_VARIANT (t) == short_unsigned_type_node
4652 	      || TYPE_PRECISION (t) < TYPE_PRECISION (integer_type_node));
4653 
4654     case ENUMERAL_TYPE:
4655       /* ??? Technically all enumerations not larger than an int
4656 	 promote to an int.  But this is used along code paths
4657 	 that only want to notice a size change.  */
4658       return TYPE_PRECISION (t) < TYPE_PRECISION (integer_type_node);
4659 
4660     case BOOLEAN_TYPE:
4661       return true;
4662 
4663     default:
4664       return false;
4665     }
4666 }
4667 
4668 /* Return 1 if PARMS specifies a fixed number of parameters
4669    and none of their types is affected by default promotions.  */
4670 
4671 bool
4672 self_promoting_args_p (const_tree parms)
4673 {
4674   const_tree t;
4675   for (t = parms; t; t = TREE_CHAIN (t))
4676     {
4677       tree type = TREE_VALUE (t);
4678 
4679       if (type == error_mark_node)
4680 	continue;
4681 
4682       if (TREE_CHAIN (t) == NULL_TREE && type != void_type_node)
4683 	return false;
4684 
4685       if (type == NULL_TREE)
4686 	return false;
4687 
4688       if (TYPE_MAIN_VARIANT (type) == float_type_node)
4689 	return false;
4690 
4691       if (c_promoting_integer_type_p (type))
4692 	return false;
4693     }
4694   return true;
4695 }
4696 
4697 /* Recursively remove any '*' or '&' operator from TYPE.  */
4698 tree
4699 strip_pointer_operator (tree t)
4700 {
4701   while (POINTER_TYPE_P (t))
4702     t = TREE_TYPE (t);
4703   return t;
4704 }
4705 
4706 /* Recursively remove pointer or array type from TYPE. */
4707 tree
4708 strip_pointer_or_array_types (tree t)
4709 {
4710   while (TREE_CODE (t) == ARRAY_TYPE || POINTER_TYPE_P (t))
4711     t = TREE_TYPE (t);
4712   return t;
4713 }
4714 
4715 /* Used to compare case labels.  K1 and K2 are actually tree nodes
4716    representing case labels, or NULL_TREE for a `default' label.
4717    Returns -1 if K1 is ordered before K2, -1 if K1 is ordered after
4718    K2, and 0 if K1 and K2 are equal.  */
4719 
4720 int
4721 case_compare (splay_tree_key k1, splay_tree_key k2)
4722 {
4723   /* Consider a NULL key (such as arises with a `default' label) to be
4724      smaller than anything else.  */
4725   if (!k1)
4726     return k2 ? -1 : 0;
4727   else if (!k2)
4728     return k1 ? 1 : 0;
4729 
4730   return tree_int_cst_compare ((tree) k1, (tree) k2);
4731 }
4732 
4733 /* Process a case label, located at LOC, for the range LOW_VALUE
4734    ... HIGH_VALUE.  If LOW_VALUE and HIGH_VALUE are both NULL_TREE
4735    then this case label is actually a `default' label.  If only
4736    HIGH_VALUE is NULL_TREE, then case label was declared using the
4737    usual C/C++ syntax, rather than the GNU case range extension.
4738    CASES is a tree containing all the case ranges processed so far;
4739    COND is the condition for the switch-statement itself.
4740    OUTSIDE_RANGE_P says whether there was a case value that doesn't
4741    fit into the range of the ORIG_TYPE.  Returns the CASE_LABEL_EXPR
4742    created, or ERROR_MARK_NODE if no CASE_LABEL_EXPR is created.  */
4743 
4744 tree
4745 c_add_case_label (location_t loc, splay_tree cases, tree cond, tree orig_type,
4746 		  tree low_value, tree high_value, bool *outside_range_p)
4747 {
4748   tree type;
4749   tree label;
4750   tree case_label;
4751   splay_tree_node node;
4752 
4753   /* Create the LABEL_DECL itself.  */
4754   label = create_artificial_label (loc);
4755 
4756   /* If there was an error processing the switch condition, bail now
4757      before we get more confused.  */
4758   if (!cond || cond == error_mark_node)
4759     goto error_out;
4760 
4761   if ((low_value && TREE_TYPE (low_value)
4762        && POINTER_TYPE_P (TREE_TYPE (low_value)))
4763       || (high_value && TREE_TYPE (high_value)
4764 	  && POINTER_TYPE_P (TREE_TYPE (high_value))))
4765     {
4766       error_at (loc, "pointers are not permitted as case values");
4767       goto error_out;
4768     }
4769 
4770   /* Case ranges are a GNU extension.  */
4771   if (high_value)
4772     pedwarn (loc, OPT_Wpedantic,
4773 	     "range expressions in switch statements are non-standard");
4774 
4775   type = TREE_TYPE (cond);
4776   if (low_value)
4777     {
4778       low_value = check_case_value (loc, low_value);
4779       low_value = convert_and_check (loc, type, low_value);
4780       if (low_value == error_mark_node)
4781 	goto error_out;
4782     }
4783   if (high_value)
4784     {
4785       high_value = check_case_value (loc, high_value);
4786       high_value = convert_and_check (loc, type, high_value);
4787       if (high_value == error_mark_node)
4788 	goto error_out;
4789     }
4790 
4791   if (low_value && high_value)
4792     {
4793       /* If the LOW_VALUE and HIGH_VALUE are the same, then this isn't
4794 	 really a case range, even though it was written that way.
4795 	 Remove the HIGH_VALUE to simplify later processing.  */
4796       if (tree_int_cst_equal (low_value, high_value))
4797 	high_value = NULL_TREE;
4798       else if (!tree_int_cst_lt (low_value, high_value))
4799 	warning_at (loc, 0, "empty range specified");
4800     }
4801 
4802   /* See if the case is in range of the type of the original testing
4803      expression.  If both low_value and high_value are out of range,
4804      don't insert the case label and return NULL_TREE.  */
4805   if (low_value
4806       && !check_case_bounds (loc, type, orig_type,
4807 			     &low_value, high_value ? &high_value : NULL,
4808 			     outside_range_p))
4809     return NULL_TREE;
4810 
4811   /* Look up the LOW_VALUE in the table of case labels we already
4812      have.  */
4813   node = splay_tree_lookup (cases, (splay_tree_key) low_value);
4814   /* If there was not an exact match, check for overlapping ranges.
4815      There's no need to do this if there's no LOW_VALUE or HIGH_VALUE;
4816      that's a `default' label and the only overlap is an exact match.  */
4817   if (!node && (low_value || high_value))
4818     {
4819       splay_tree_node low_bound;
4820       splay_tree_node high_bound;
4821 
4822       /* Even though there wasn't an exact match, there might be an
4823 	 overlap between this case range and another case range.
4824 	 Since we've (inductively) not allowed any overlapping case
4825 	 ranges, we simply need to find the greatest low case label
4826 	 that is smaller that LOW_VALUE, and the smallest low case
4827 	 label that is greater than LOW_VALUE.  If there is an overlap
4828 	 it will occur in one of these two ranges.  */
4829       low_bound = splay_tree_predecessor (cases,
4830 					  (splay_tree_key) low_value);
4831       high_bound = splay_tree_successor (cases,
4832 					 (splay_tree_key) low_value);
4833 
4834       /* Check to see if the LOW_BOUND overlaps.  It is smaller than
4835 	 the LOW_VALUE, so there is no need to check unless the
4836 	 LOW_BOUND is in fact itself a case range.  */
4837       if (low_bound
4838 	  && CASE_HIGH ((tree) low_bound->value)
4839 	  && tree_int_cst_compare (CASE_HIGH ((tree) low_bound->value),
4840 				    low_value) >= 0)
4841 	node = low_bound;
4842       /* Check to see if the HIGH_BOUND overlaps.  The low end of that
4843 	 range is bigger than the low end of the current range, so we
4844 	 are only interested if the current range is a real range, and
4845 	 not an ordinary case label.  */
4846       else if (high_bound
4847 	       && high_value
4848 	       && (tree_int_cst_compare ((tree) high_bound->key,
4849 					 high_value)
4850 		   <= 0))
4851 	node = high_bound;
4852     }
4853   /* If there was an overlap, issue an error.  */
4854   if (node)
4855     {
4856       tree duplicate = CASE_LABEL ((tree) node->value);
4857 
4858       if (high_value)
4859 	{
4860 	  error_at (loc, "duplicate (or overlapping) case value");
4861 	  inform (DECL_SOURCE_LOCATION (duplicate),
4862 		  "this is the first entry overlapping that value");
4863 	}
4864       else if (low_value)
4865 	{
4866 	  error_at (loc, "duplicate case value") ;
4867 	  inform (DECL_SOURCE_LOCATION (duplicate), "previously used here");
4868 	}
4869       else
4870 	{
4871 	  error_at (loc, "multiple default labels in one switch");
4872 	  inform (DECL_SOURCE_LOCATION (duplicate),
4873 		  "this is the first default label");
4874 	}
4875       goto error_out;
4876     }
4877 
4878   /* Add a CASE_LABEL to the statement-tree.  */
4879   case_label = add_stmt (build_case_label (low_value, high_value, label));
4880   /* Register this case label in the splay tree.  */
4881   splay_tree_insert (cases,
4882 		     (splay_tree_key) low_value,
4883 		     (splay_tree_value) case_label);
4884 
4885   return case_label;
4886 
4887  error_out:
4888   /* Add a label so that the back-end doesn't think that the beginning of
4889      the switch is unreachable.  Note that we do not add a case label, as
4890      that just leads to duplicates and thence to failure later on.  */
4891   if (!cases->root)
4892     {
4893       tree t = create_artificial_label (loc);
4894       add_stmt (build_stmt (loc, LABEL_EXPR, t));
4895     }
4896   return error_mark_node;
4897 }
4898 
4899 /* Subroutine of c_switch_covers_all_cases_p, called via
4900    splay_tree_foreach.  Return 1 if it doesn't cover all the cases.
4901    ARGS[0] is initially NULL and after the first iteration is the
4902    so far highest case label.  ARGS[1] is the minimum of SWITCH_COND's
4903    type.  */
4904 
4905 static int
4906 c_switch_covers_all_cases_p_1 (splay_tree_node node, void *data)
4907 {
4908   tree label = (tree) node->value;
4909   tree *args = (tree *) data;
4910 
4911   /* If there is a default case, we shouldn't have called this.  */
4912   gcc_assert (CASE_LOW (label));
4913 
4914   if (args[0] == NULL_TREE)
4915     {
4916       if (wi::to_widest (args[1]) < wi::to_widest (CASE_LOW (label)))
4917 	return 1;
4918     }
4919   else if (wi::add (wi::to_widest (args[0]), 1)
4920 	   != wi::to_widest (CASE_LOW (label)))
4921     return 1;
4922   if (CASE_HIGH (label))
4923     args[0] = CASE_HIGH (label);
4924   else
4925     args[0] = CASE_LOW (label);
4926   return 0;
4927 }
4928 
4929 /* Return true if switch with CASES and switch condition with type
4930    covers all possible values in the case labels.  */
4931 
4932 bool
4933 c_switch_covers_all_cases_p (splay_tree cases, tree type)
4934 {
4935   /* If there is default:, this is always the case.  */
4936   splay_tree_node default_node
4937     = splay_tree_lookup (cases, (splay_tree_key) NULL);
4938   if (default_node)
4939     return true;
4940 
4941   if (!INTEGRAL_TYPE_P (type))
4942     return false;
4943 
4944   tree args[2] = { NULL_TREE, TYPE_MIN_VALUE (type) };
4945   if (splay_tree_foreach (cases, c_switch_covers_all_cases_p_1, args))
4946     return false;
4947 
4948   /* If there are no cases at all, or if the highest case label
4949      is smaller than TYPE_MAX_VALUE, return false.  */
4950   if (args[0] == NULL_TREE
4951       || wi::to_widest (args[0]) < wi::to_widest (TYPE_MAX_VALUE (type)))
4952     return false;
4953 
4954   return true;
4955 }
4956 
4957 /* Finish an expression taking the address of LABEL (an
4958    IDENTIFIER_NODE).  Returns an expression for the address.
4959 
4960    LOC is the location for the expression returned.  */
4961 
4962 tree
4963 finish_label_address_expr (tree label, location_t loc)
4964 {
4965   tree result;
4966 
4967   pedwarn (input_location, OPT_Wpedantic, "taking the address of a label is non-standard");
4968 
4969   if (label == error_mark_node)
4970     return error_mark_node;
4971 
4972   label = lookup_label (label);
4973   if (label == NULL_TREE)
4974     result = null_pointer_node;
4975   else
4976     {
4977       TREE_USED (label) = 1;
4978       result = build1 (ADDR_EXPR, ptr_type_node, label);
4979       /* The current function is not necessarily uninlinable.
4980 	 Computed gotos are incompatible with inlining, but the value
4981 	 here could be used only in a diagnostic, for example.  */
4982       protected_set_expr_location (result, loc);
4983     }
4984 
4985   return result;
4986 }
4987 
4988 
4989 /* Given a boolean expression ARG, return a tree representing an increment
4990    or decrement (as indicated by CODE) of ARG.  The front end must check for
4991    invalid cases (e.g., decrement in C++).  */
4992 tree
4993 boolean_increment (enum tree_code code, tree arg)
4994 {
4995   tree val;
4996   tree true_res = build_int_cst (TREE_TYPE (arg), 1);
4997 
4998   arg = stabilize_reference (arg);
4999   switch (code)
5000     {
5001     case PREINCREMENT_EXPR:
5002       val = build2 (MODIFY_EXPR, TREE_TYPE (arg), arg, true_res);
5003       break;
5004     case POSTINCREMENT_EXPR:
5005       val = build2 (MODIFY_EXPR, TREE_TYPE (arg), arg, true_res);
5006       arg = save_expr (arg);
5007       val = build2 (COMPOUND_EXPR, TREE_TYPE (arg), val, arg);
5008       val = build2 (COMPOUND_EXPR, TREE_TYPE (arg), arg, val);
5009       break;
5010     case PREDECREMENT_EXPR:
5011       val = build2 (MODIFY_EXPR, TREE_TYPE (arg), arg,
5012 		    invert_truthvalue_loc (input_location, arg));
5013       break;
5014     case POSTDECREMENT_EXPR:
5015       val = build2 (MODIFY_EXPR, TREE_TYPE (arg), arg,
5016 		    invert_truthvalue_loc (input_location, arg));
5017       arg = save_expr (arg);
5018       val = build2 (COMPOUND_EXPR, TREE_TYPE (arg), val, arg);
5019       val = build2 (COMPOUND_EXPR, TREE_TYPE (arg), arg, val);
5020       break;
5021     default:
5022       gcc_unreachable ();
5023     }
5024   TREE_SIDE_EFFECTS (val) = 1;
5025   return val;
5026 }
5027 
5028 /* Built-in macros for stddef.h and stdint.h, that require macros
5029    defined in this file.  */
5030 void
5031 c_stddef_cpp_builtins(void)
5032 {
5033   builtin_define_with_value ("__SIZE_TYPE__", SIZE_TYPE, 0);
5034   builtin_define_with_value ("__PTRDIFF_TYPE__", PTRDIFF_TYPE, 0);
5035   builtin_define_with_value ("__WCHAR_TYPE__", MODIFIED_WCHAR_TYPE, 0);
5036   builtin_define_with_value ("__WINT_TYPE__", WINT_TYPE, 0);
5037   builtin_define_with_value ("__INTMAX_TYPE__", INTMAX_TYPE, 0);
5038   builtin_define_with_value ("__UINTMAX_TYPE__", UINTMAX_TYPE, 0);
5039   builtin_define_with_value ("__CHAR16_TYPE__", CHAR16_TYPE, 0);
5040   builtin_define_with_value ("__CHAR32_TYPE__", CHAR32_TYPE, 0);
5041   if (SIG_ATOMIC_TYPE)
5042     builtin_define_with_value ("__SIG_ATOMIC_TYPE__", SIG_ATOMIC_TYPE, 0);
5043   if (INT8_TYPE)
5044     builtin_define_with_value ("__INT8_TYPE__", INT8_TYPE, 0);
5045   if (INT16_TYPE)
5046     builtin_define_with_value ("__INT16_TYPE__", INT16_TYPE, 0);
5047   if (INT32_TYPE)
5048     builtin_define_with_value ("__INT32_TYPE__", INT32_TYPE, 0);
5049   if (INT64_TYPE)
5050     builtin_define_with_value ("__INT64_TYPE__", INT64_TYPE, 0);
5051   if (UINT8_TYPE)
5052     builtin_define_with_value ("__UINT8_TYPE__", UINT8_TYPE, 0);
5053   if (UINT16_TYPE)
5054     builtin_define_with_value ("__UINT16_TYPE__", UINT16_TYPE, 0);
5055   if (UINT32_TYPE)
5056     builtin_define_with_value ("__UINT32_TYPE__", UINT32_TYPE, 0);
5057   if (UINT64_TYPE)
5058     builtin_define_with_value ("__UINT64_TYPE__", UINT64_TYPE, 0);
5059   if (INT_LEAST8_TYPE)
5060     builtin_define_with_value ("__INT_LEAST8_TYPE__", INT_LEAST8_TYPE, 0);
5061   if (INT_LEAST16_TYPE)
5062     builtin_define_with_value ("__INT_LEAST16_TYPE__", INT_LEAST16_TYPE, 0);
5063   if (INT_LEAST32_TYPE)
5064     builtin_define_with_value ("__INT_LEAST32_TYPE__", INT_LEAST32_TYPE, 0);
5065   if (INT_LEAST64_TYPE)
5066     builtin_define_with_value ("__INT_LEAST64_TYPE__", INT_LEAST64_TYPE, 0);
5067   if (UINT_LEAST8_TYPE)
5068     builtin_define_with_value ("__UINT_LEAST8_TYPE__", UINT_LEAST8_TYPE, 0);
5069   if (UINT_LEAST16_TYPE)
5070     builtin_define_with_value ("__UINT_LEAST16_TYPE__", UINT_LEAST16_TYPE, 0);
5071   if (UINT_LEAST32_TYPE)
5072     builtin_define_with_value ("__UINT_LEAST32_TYPE__", UINT_LEAST32_TYPE, 0);
5073   if (UINT_LEAST64_TYPE)
5074     builtin_define_with_value ("__UINT_LEAST64_TYPE__", UINT_LEAST64_TYPE, 0);
5075   if (INT_FAST8_TYPE)
5076     builtin_define_with_value ("__INT_FAST8_TYPE__", INT_FAST8_TYPE, 0);
5077   if (INT_FAST16_TYPE)
5078     builtin_define_with_value ("__INT_FAST16_TYPE__", INT_FAST16_TYPE, 0);
5079   if (INT_FAST32_TYPE)
5080     builtin_define_with_value ("__INT_FAST32_TYPE__", INT_FAST32_TYPE, 0);
5081   if (INT_FAST64_TYPE)
5082     builtin_define_with_value ("__INT_FAST64_TYPE__", INT_FAST64_TYPE, 0);
5083   if (UINT_FAST8_TYPE)
5084     builtin_define_with_value ("__UINT_FAST8_TYPE__", UINT_FAST8_TYPE, 0);
5085   if (UINT_FAST16_TYPE)
5086     builtin_define_with_value ("__UINT_FAST16_TYPE__", UINT_FAST16_TYPE, 0);
5087   if (UINT_FAST32_TYPE)
5088     builtin_define_with_value ("__UINT_FAST32_TYPE__", UINT_FAST32_TYPE, 0);
5089   if (UINT_FAST64_TYPE)
5090     builtin_define_with_value ("__UINT_FAST64_TYPE__", UINT_FAST64_TYPE, 0);
5091   if (INTPTR_TYPE)
5092     builtin_define_with_value ("__INTPTR_TYPE__", INTPTR_TYPE, 0);
5093   if (UINTPTR_TYPE)
5094     builtin_define_with_value ("__UINTPTR_TYPE__", UINTPTR_TYPE, 0);
5095 }
5096 
5097 static void
5098 c_init_attributes (void)
5099 {
5100   /* Fill in the built_in_attributes array.  */
5101 #define DEF_ATTR_NULL_TREE(ENUM)				\
5102   built_in_attributes[(int) ENUM] = NULL_TREE;
5103 #define DEF_ATTR_INT(ENUM, VALUE)				\
5104   built_in_attributes[(int) ENUM] = build_int_cst (integer_type_node, VALUE);
5105 #define DEF_ATTR_STRING(ENUM, VALUE)				\
5106   built_in_attributes[(int) ENUM] = build_string (strlen (VALUE), VALUE);
5107 #define DEF_ATTR_IDENT(ENUM, STRING)				\
5108   built_in_attributes[(int) ENUM] = get_identifier (STRING);
5109 #define DEF_ATTR_TREE_LIST(ENUM, PURPOSE, VALUE, CHAIN)	\
5110   built_in_attributes[(int) ENUM]			\
5111     = tree_cons (built_in_attributes[(int) PURPOSE],	\
5112 		 built_in_attributes[(int) VALUE],	\
5113 		 built_in_attributes[(int) CHAIN]);
5114 #include "builtin-attrs.def"
5115 #undef DEF_ATTR_NULL_TREE
5116 #undef DEF_ATTR_INT
5117 #undef DEF_ATTR_IDENT
5118 #undef DEF_ATTR_TREE_LIST
5119 }
5120 
5121 /* Check whether ALIGN is a valid user-specified alignment.  If so,
5122    return its base-2 log; if not, output an error and return -1.  If
5123    ALLOW_ZERO then 0 is valid and should result in a return of -1 with
5124    no error.  */
5125 int
5126 check_user_alignment (const_tree align, bool allow_zero)
5127 {
5128   int i;
5129 
5130   if (error_operand_p (align))
5131     return -1;
5132   if (TREE_CODE (align) != INTEGER_CST
5133       || !INTEGRAL_TYPE_P (TREE_TYPE (align)))
5134     {
5135       error ("requested alignment is not an integer constant");
5136       return -1;
5137     }
5138   else if (allow_zero && integer_zerop (align))
5139     return -1;
5140   else if (tree_int_cst_sgn (align) == -1
5141            || (i = tree_log2 (align)) == -1)
5142     {
5143       error ("requested alignment is not a positive power of 2");
5144       return -1;
5145     }
5146   else if (i >= HOST_BITS_PER_INT - LOG2_BITS_PER_UNIT)
5147     {
5148       error ("requested alignment is too large");
5149       return -1;
5150     }
5151   return i;
5152 }
5153 
5154 /* Determine the ELF symbol visibility for DECL, which is either a
5155    variable or a function.  It is an error to use this function if a
5156    definition of DECL is not available in this translation unit.
5157    Returns true if the final visibility has been determined by this
5158    function; false if the caller is free to make additional
5159    modifications.  */
5160 
5161 bool
5162 c_determine_visibility (tree decl)
5163 {
5164   gcc_assert (VAR_OR_FUNCTION_DECL_P (decl));
5165 
5166   /* If the user explicitly specified the visibility with an
5167      attribute, honor that.  DECL_VISIBILITY will have been set during
5168      the processing of the attribute.  We check for an explicit
5169      attribute, rather than just checking DECL_VISIBILITY_SPECIFIED,
5170      to distinguish the use of an attribute from the use of a "#pragma
5171      GCC visibility push(...)"; in the latter case we still want other
5172      considerations to be able to overrule the #pragma.  */
5173   if (lookup_attribute ("visibility", DECL_ATTRIBUTES (decl))
5174       || (TARGET_DLLIMPORT_DECL_ATTRIBUTES
5175 	  && (lookup_attribute ("dllimport", DECL_ATTRIBUTES (decl))
5176 	      || lookup_attribute ("dllexport", DECL_ATTRIBUTES (decl)))))
5177     return true;
5178 
5179   /* Set default visibility to whatever the user supplied with
5180      visibility_specified depending on #pragma GCC visibility.  */
5181   if (!DECL_VISIBILITY_SPECIFIED (decl))
5182     {
5183       if (visibility_options.inpragma
5184 	  || DECL_VISIBILITY (decl) != default_visibility)
5185 	{
5186 	  DECL_VISIBILITY (decl) = default_visibility;
5187 	  DECL_VISIBILITY_SPECIFIED (decl) = visibility_options.inpragma;
5188 	  /* If visibility changed and DECL already has DECL_RTL, ensure
5189 	     symbol flags are updated.  */
5190 	  if (((VAR_P (decl) && TREE_STATIC (decl))
5191 	       || TREE_CODE (decl) == FUNCTION_DECL)
5192 	      && DECL_RTL_SET_P (decl))
5193 	    make_decl_rtl (decl);
5194 	}
5195     }
5196   return false;
5197 }
5198 
5199 /* Data to communicate through check_function_arguments_recurse between
5200    check_function_nonnull and check_nonnull_arg.  */
5201 
5202 struct nonnull_arg_ctx
5203 {
5204   location_t loc;
5205   bool warned_p;
5206 };
5207 
5208 /* Check the argument list of a function call for null in argument slots
5209    that are marked as requiring a non-null pointer argument.  The NARGS
5210    arguments are passed in the array ARGARRAY.  Return true if we have
5211    warned.  */
5212 
5213 static bool
5214 check_function_nonnull (location_t loc, tree attrs, int nargs, tree *argarray)
5215 {
5216   tree a;
5217   int i;
5218 
5219   attrs = lookup_attribute ("nonnull", attrs);
5220   if (attrs == NULL_TREE)
5221     return false;
5222 
5223   a = attrs;
5224   /* See if any of the nonnull attributes has no arguments.  If so,
5225      then every pointer argument is checked (in which case the check
5226      for pointer type is done in check_nonnull_arg).  */
5227   if (TREE_VALUE (a) != NULL_TREE)
5228     do
5229       a = lookup_attribute ("nonnull", TREE_CHAIN (a));
5230     while (a != NULL_TREE && TREE_VALUE (a) != NULL_TREE);
5231 
5232   struct nonnull_arg_ctx ctx = { loc, false };
5233   if (a != NULL_TREE)
5234     for (i = 0; i < nargs; i++)
5235       check_function_arguments_recurse (check_nonnull_arg, &ctx, argarray[i],
5236 					i + 1);
5237   else
5238     {
5239       /* Walk the argument list.  If we encounter an argument number we
5240 	 should check for non-null, do it.  */
5241       for (i = 0; i < nargs; i++)
5242 	{
5243 	  for (a = attrs; ; a = TREE_CHAIN (a))
5244 	    {
5245 	      a = lookup_attribute ("nonnull", a);
5246 	      if (a == NULL_TREE || nonnull_check_p (TREE_VALUE (a), i + 1))
5247 		break;
5248 	    }
5249 
5250 	  if (a != NULL_TREE)
5251 	    check_function_arguments_recurse (check_nonnull_arg, &ctx,
5252 					      argarray[i], i + 1);
5253 	}
5254     }
5255   return ctx.warned_p;
5256 }
5257 
5258 /* Check that the Nth argument of a function call (counting backwards
5259    from the end) is a (pointer)0.  The NARGS arguments are passed in the
5260    array ARGARRAY.  */
5261 
5262 static void
5263 check_function_sentinel (const_tree fntype, int nargs, tree *argarray)
5264 {
5265   tree attr = lookup_attribute ("sentinel", TYPE_ATTRIBUTES (fntype));
5266 
5267   if (attr)
5268     {
5269       int len = 0;
5270       int pos = 0;
5271       tree sentinel;
5272       function_args_iterator iter;
5273       tree t;
5274 
5275       /* Skip over the named arguments.  */
5276       FOREACH_FUNCTION_ARGS (fntype, t, iter)
5277 	{
5278 	  if (len == nargs)
5279 	    break;
5280 	  len++;
5281 	}
5282 
5283       if (TREE_VALUE (attr))
5284 	{
5285 	  tree p = TREE_VALUE (TREE_VALUE (attr));
5286 	  pos = TREE_INT_CST_LOW (p);
5287 	}
5288 
5289       /* The sentinel must be one of the varargs, i.e.
5290 	 in position >= the number of fixed arguments.  */
5291       if ((nargs - 1 - pos) < len)
5292 	{
5293 	  warning (OPT_Wformat_,
5294 		   "not enough variable arguments to fit a sentinel");
5295 	  return;
5296 	}
5297 
5298       /* Validate the sentinel.  */
5299       sentinel = argarray[nargs - 1 - pos];
5300       if ((!POINTER_TYPE_P (TREE_TYPE (sentinel))
5301 	   || !integer_zerop (sentinel))
5302 	  /* Although __null (in C++) is only an integer we allow it
5303 	     nevertheless, as we are guaranteed that it's exactly
5304 	     as wide as a pointer, and we don't want to force
5305 	     users to cast the NULL they have written there.
5306 	     We warn with -Wstrict-null-sentinel, though.  */
5307 	  && (warn_strict_null_sentinel || null_node != sentinel))
5308 	warning (OPT_Wformat_, "missing sentinel in function call");
5309     }
5310 }
5311 
5312 /* Check that the same argument isn't passed to two or more
5313    restrict-qualified formal and issue a -Wrestrict warning
5314    if it is.  Return true if a warning has been issued.  */
5315 
5316 static bool
5317 check_function_restrict (const_tree fndecl, const_tree fntype,
5318 			 int nargs, tree *argarray)
5319 {
5320   int i;
5321   tree parms = TYPE_ARG_TYPES (fntype);
5322 
5323   if (fndecl
5324       && TREE_CODE (fndecl) == FUNCTION_DECL)
5325     {
5326       /* Avoid diagnosing calls built-ins with a zero size/bound
5327 	 here.  They are checked in more detail elsewhere.  */
5328       if (DECL_BUILT_IN (fndecl)
5329 	  && DECL_BUILT_IN_CLASS (fndecl) == BUILT_IN_NORMAL
5330 	  && nargs == 3
5331 	  && TREE_CODE (argarray[2]) == INTEGER_CST
5332 	  && integer_zerop (argarray[2]))
5333 	return false;
5334 
5335       if (DECL_ARGUMENTS (fndecl))
5336 	parms = DECL_ARGUMENTS (fndecl);
5337     }
5338 
5339   for (i = 0; i < nargs; i++)
5340     TREE_VISITED (argarray[i]) = 0;
5341 
5342   bool warned = false;
5343 
5344   for (i = 0; i < nargs && parms && parms != void_list_node; i++)
5345     {
5346       tree type;
5347       if (TREE_CODE (parms) == PARM_DECL)
5348 	{
5349 	  type = TREE_TYPE (parms);
5350 	  parms = DECL_CHAIN (parms);
5351 	}
5352       else
5353 	{
5354 	  type = TREE_VALUE (parms);
5355 	  parms = TREE_CHAIN (parms);
5356 	}
5357       if (POINTER_TYPE_P (type)
5358 	  && TYPE_RESTRICT (type)
5359 	  && !TYPE_READONLY (TREE_TYPE (type)))
5360 	warned |= warn_for_restrict (i, argarray, nargs);
5361     }
5362 
5363   for (i = 0; i < nargs; i++)
5364     TREE_VISITED (argarray[i]) = 0;
5365 
5366   return warned;
5367 }
5368 
5369 /* Helper for check_function_nonnull; given a list of operands which
5370    must be non-null in ARGS, determine if operand PARAM_NUM should be
5371    checked.  */
5372 
5373 static bool
5374 nonnull_check_p (tree args, unsigned HOST_WIDE_INT param_num)
5375 {
5376   unsigned HOST_WIDE_INT arg_num = 0;
5377 
5378   for (; args; args = TREE_CHAIN (args))
5379     {
5380       bool found = get_nonnull_operand (TREE_VALUE (args), &arg_num);
5381 
5382       gcc_assert (found);
5383 
5384       if (arg_num == param_num)
5385 	return true;
5386     }
5387   return false;
5388 }
5389 
5390 /* Check that the function argument PARAM (which is operand number
5391    PARAM_NUM) is non-null.  This is called by check_function_nonnull
5392    via check_function_arguments_recurse.  */
5393 
5394 static void
5395 check_nonnull_arg (void *ctx, tree param, unsigned HOST_WIDE_INT param_num)
5396 {
5397   struct nonnull_arg_ctx *pctx = (struct nonnull_arg_ctx *) ctx;
5398 
5399   /* Just skip checking the argument if it's not a pointer.  This can
5400      happen if the "nonnull" attribute was given without an operand
5401      list (which means to check every pointer argument).  */
5402 
5403   if (TREE_CODE (TREE_TYPE (param)) != POINTER_TYPE)
5404     return;
5405 
5406   /* Diagnose the simple cases of null arguments.  */
5407   if (integer_zerop (fold_for_warn (param)))
5408     {
5409       warning_at (pctx->loc, OPT_Wnonnull, "null argument where non-null "
5410 		  "required (argument %lu)", (unsigned long) param_num);
5411       pctx->warned_p = true;
5412     }
5413 }
5414 
5415 /* Helper for nonnull attribute handling; fetch the operand number
5416    from the attribute argument list.  */
5417 
5418 bool
5419 get_nonnull_operand (tree arg_num_expr, unsigned HOST_WIDE_INT *valp)
5420 {
5421   /* Verify the arg number is a small constant.  */
5422   if (tree_fits_uhwi_p (arg_num_expr))
5423     {
5424       *valp = tree_to_uhwi (arg_num_expr);
5425       return true;
5426     }
5427   else
5428     return false;
5429 }
5430 
5431 /* Arguments being collected for optimization.  */
5432 typedef const char *const_char_p;		/* For DEF_VEC_P.  */
5433 static GTY(()) vec<const_char_p, va_gc> *optimize_args;
5434 
5435 
5436 /* Inner function to convert a TREE_LIST to argv string to parse the optimize
5437    options in ARGS.  ATTR_P is true if this is for attribute(optimize), and
5438    false for #pragma GCC optimize.  */
5439 
5440 bool
5441 parse_optimize_options (tree args, bool attr_p)
5442 {
5443   bool ret = true;
5444   unsigned opt_argc;
5445   unsigned i;
5446   const char **opt_argv;
5447   struct cl_decoded_option *decoded_options;
5448   unsigned int decoded_options_count;
5449   tree ap;
5450 
5451   /* Build up argv vector.  Just in case the string is stored away, use garbage
5452      collected strings.  */
5453   vec_safe_truncate (optimize_args, 0);
5454   vec_safe_push (optimize_args, (const char *) NULL);
5455 
5456   for (ap = args; ap != NULL_TREE; ap = TREE_CHAIN (ap))
5457     {
5458       tree value = TREE_VALUE (ap);
5459 
5460       if (TREE_CODE (value) == INTEGER_CST)
5461 	{
5462 	  char buffer[20];
5463 	  sprintf (buffer, "-O%ld", (long) TREE_INT_CST_LOW (value));
5464 	  vec_safe_push (optimize_args, ggc_strdup (buffer));
5465 	}
5466 
5467       else if (TREE_CODE (value) == STRING_CST)
5468 	{
5469 	  /* Split string into multiple substrings.  */
5470 	  size_t len = TREE_STRING_LENGTH (value);
5471 	  char *p = ASTRDUP (TREE_STRING_POINTER (value));
5472 	  char *end = p + len;
5473 	  char *comma;
5474 	  char *next_p = p;
5475 
5476 	  while (next_p != NULL)
5477 	    {
5478 	      size_t len2;
5479 	      char *q, *r;
5480 
5481 	      p = next_p;
5482 	      comma = strchr (p, ',');
5483 	      if (comma)
5484 		{
5485 		  len2 = comma - p;
5486 		  *comma = '\0';
5487 		  next_p = comma+1;
5488 		}
5489 	      else
5490 		{
5491 		  len2 = end - p;
5492 		  next_p = NULL;
5493 		}
5494 
5495 	      r = q = (char *) ggc_alloc_atomic (len2 + 3);
5496 
5497 	      /* If the user supplied -Oxxx or -fxxx, only allow -Oxxx or -fxxx
5498 		 options.  */
5499 	      if (*p == '-' && p[1] != 'O' && p[1] != 'f')
5500 		{
5501 		  ret = false;
5502 		  if (attr_p)
5503 		    warning (OPT_Wattributes,
5504 			     "bad option %qs to attribute %<optimize%>", p);
5505 		  else
5506 		    warning (OPT_Wpragmas,
5507 			     "bad option %qs to pragma %<optimize%>", p);
5508 		  continue;
5509 		}
5510 
5511 	      if (*p != '-')
5512 		{
5513 		  *r++ = '-';
5514 
5515 		  /* Assume that Ox is -Ox, a numeric value is -Ox, a s by
5516 		     itself is -Os, and any other switch begins with a -f.  */
5517 		  if ((*p >= '0' && *p <= '9')
5518 		      || (p[0] == 's' && p[1] == '\0'))
5519 		    *r++ = 'O';
5520 		  else if (*p != 'O')
5521 		    *r++ = 'f';
5522 		}
5523 
5524 	      memcpy (r, p, len2);
5525 	      r[len2] = '\0';
5526 	      vec_safe_push (optimize_args, (const char *) q);
5527 	    }
5528 
5529 	}
5530     }
5531 
5532   opt_argc = optimize_args->length ();
5533   opt_argv = (const char **) alloca (sizeof (char *) * (opt_argc + 1));
5534 
5535   for (i = 1; i < opt_argc; i++)
5536     opt_argv[i] = (*optimize_args)[i];
5537 
5538   /* Now parse the options.  */
5539   decode_cmdline_options_to_array_default_mask (opt_argc, opt_argv,
5540 						&decoded_options,
5541 						&decoded_options_count);
5542   /* Drop non-Optimization options.  */
5543   unsigned j = 1;
5544   for (i = 1; i < decoded_options_count; ++i)
5545     {
5546       if (! (cl_options[decoded_options[i].opt_index].flags & CL_OPTIMIZATION))
5547 	{
5548 	  ret = false;
5549 	  if (attr_p)
5550 	    warning (OPT_Wattributes,
5551 		     "bad option %qs to attribute %<optimize%>",
5552 		     decoded_options[i].orig_option_with_args_text);
5553 	  else
5554 	    warning (OPT_Wpragmas,
5555 		     "bad option %qs to pragma %<optimize%>",
5556 		     decoded_options[i].orig_option_with_args_text);
5557 	  continue;
5558 	}
5559       if (i != j)
5560 	decoded_options[j] = decoded_options[i];
5561       j++;
5562     }
5563   decoded_options_count = j;
5564   /* And apply them.  */
5565   decode_options (&global_options, &global_options_set,
5566 		  decoded_options, decoded_options_count,
5567 		  input_location, global_dc, NULL);
5568 
5569   targetm.override_options_after_change();
5570 
5571   optimize_args->truncate (0);
5572   return ret;
5573 }
5574 
5575 /* Check whether ATTR is a valid attribute fallthrough.  */
5576 
5577 bool
5578 attribute_fallthrough_p (tree attr)
5579 {
5580   if (attr == error_mark_node)
5581    return false;
5582   tree t = lookup_attribute ("fallthrough", attr);
5583   if (t == NULL_TREE)
5584     return false;
5585   /* This attribute shall appear at most once in each attribute-list.  */
5586   if (lookup_attribute ("fallthrough", TREE_CHAIN (t)))
5587     warning (OPT_Wattributes, "%<fallthrough%> attribute specified multiple "
5588 	     "times");
5589   /* No attribute-argument-clause shall be present.  */
5590   else if (TREE_VALUE (t) != NULL_TREE)
5591     warning (OPT_Wattributes, "%<fallthrough%> attribute specified with "
5592 	     "a parameter");
5593   /* Warn if other attributes are found.  */
5594   for (t = attr; t != NULL_TREE; t = TREE_CHAIN (t))
5595     {
5596       tree name = get_attribute_name (t);
5597       if (!is_attribute_p ("fallthrough", name))
5598 	warning (OPT_Wattributes, "%qE attribute ignored", name);
5599     }
5600   return true;
5601 }
5602 
5603 
5604 /* Check for valid arguments being passed to a function with FNTYPE.
5605    There are NARGS arguments in the array ARGARRAY.  LOC should be used
5606    for diagnostics.  Return true if either -Wnonnull or -Wrestrict has
5607    been issued.  */
5608 
5609 bool
5610 check_function_arguments (location_t loc, const_tree fndecl, const_tree fntype,
5611 			  int nargs, tree *argarray, vec<location_t> *arglocs)
5612 {
5613   bool warned_p = false;
5614 
5615   /* Check for null being passed in a pointer argument that must be
5616      non-null.  We also need to do this if format checking is enabled.  */
5617 
5618   if (warn_nonnull)
5619     warned_p = check_function_nonnull (loc, TYPE_ATTRIBUTES (fntype),
5620 				       nargs, argarray);
5621 
5622   /* Check for errors in format strings.  */
5623 
5624   if (warn_format || warn_suggest_attribute_format)
5625     check_function_format (TYPE_ATTRIBUTES (fntype), nargs, argarray, arglocs);
5626 
5627   if (warn_format)
5628     check_function_sentinel (fntype, nargs, argarray);
5629 
5630   if (warn_restrict)
5631     warned_p |= check_function_restrict (fndecl, fntype, nargs, argarray);
5632   return warned_p;
5633 }
5634 
5635 /* Generic argument checking recursion routine.  PARAM is the argument to
5636    be checked.  PARAM_NUM is the number of the argument.  CALLBACK is invoked
5637    once the argument is resolved.  CTX is context for the callback.  */
5638 void
5639 check_function_arguments_recurse (void (*callback)
5640 				  (void *, tree, unsigned HOST_WIDE_INT),
5641 				  void *ctx, tree param,
5642 				  unsigned HOST_WIDE_INT param_num)
5643 {
5644   if (CONVERT_EXPR_P (param)
5645       && (TYPE_PRECISION (TREE_TYPE (param))
5646 	  == TYPE_PRECISION (TREE_TYPE (TREE_OPERAND (param, 0)))))
5647     {
5648       /* Strip coercion.  */
5649       check_function_arguments_recurse (callback, ctx,
5650 					TREE_OPERAND (param, 0), param_num);
5651       return;
5652     }
5653 
5654   if (TREE_CODE (param) == CALL_EXPR)
5655     {
5656       tree type = TREE_TYPE (TREE_TYPE (CALL_EXPR_FN (param)));
5657       tree attrs;
5658       bool found_format_arg = false;
5659 
5660       /* See if this is a call to a known internationalization function
5661 	 that modifies a format arg.  Such a function may have multiple
5662 	 format_arg attributes (for example, ngettext).  */
5663 
5664       for (attrs = TYPE_ATTRIBUTES (type);
5665 	   attrs;
5666 	   attrs = TREE_CHAIN (attrs))
5667 	if (is_attribute_p ("format_arg", TREE_PURPOSE (attrs)))
5668 	  {
5669 	    tree inner_arg;
5670 	    tree format_num_expr;
5671 	    int format_num;
5672 	    int i;
5673 	    call_expr_arg_iterator iter;
5674 
5675 	    /* Extract the argument number, which was previously checked
5676 	       to be valid.  */
5677 	    format_num_expr = TREE_VALUE (TREE_VALUE (attrs));
5678 
5679 	    format_num = tree_to_uhwi (format_num_expr);
5680 
5681 	    for (inner_arg = first_call_expr_arg (param, &iter), i = 1;
5682 		 inner_arg != NULL_TREE;
5683 		 inner_arg = next_call_expr_arg (&iter), i++)
5684 	      if (i == format_num)
5685 		{
5686 		  check_function_arguments_recurse (callback, ctx,
5687 						    inner_arg, param_num);
5688 		  found_format_arg = true;
5689 		  break;
5690 		}
5691 	  }
5692 
5693       /* If we found a format_arg attribute and did a recursive check,
5694 	 we are done with checking this argument.  Otherwise, we continue
5695 	 and this will be considered a non-literal.  */
5696       if (found_format_arg)
5697 	return;
5698     }
5699 
5700   if (TREE_CODE (param) == COND_EXPR)
5701     {
5702       /* Simplify to avoid warning for an impossible case.  */
5703       param = fold_for_warn (param);
5704       if (TREE_CODE (param) == COND_EXPR)
5705 	{
5706 	  /* Check both halves of the conditional expression.  */
5707 	  check_function_arguments_recurse (callback, ctx,
5708 					    TREE_OPERAND (param, 1),
5709 					    param_num);
5710 	  check_function_arguments_recurse (callback, ctx,
5711 					    TREE_OPERAND (param, 2),
5712 					    param_num);
5713 	  return;
5714 	}
5715     }
5716 
5717   (*callback) (ctx, param, param_num);
5718 }
5719 
5720 /* Checks for a builtin function FNDECL that the number of arguments
5721    NARGS against the required number REQUIRED and issues an error if
5722    there is a mismatch.  Returns true if the number of arguments is
5723    correct, otherwise false.  LOC is the location of FNDECL.  */
5724 
5725 static bool
5726 builtin_function_validate_nargs (location_t loc, tree fndecl, int nargs,
5727 				 int required)
5728 {
5729   if (nargs < required)
5730     {
5731       error_at (loc, "too few arguments to function %qE", fndecl);
5732       return false;
5733     }
5734   else if (nargs > required)
5735     {
5736       error_at (loc, "too many arguments to function %qE", fndecl);
5737       return false;
5738     }
5739   return true;
5740 }
5741 
5742 /* Helper macro for check_builtin_function_arguments.  */
5743 #define ARG_LOCATION(N)					\
5744   (arg_loc.is_empty ()					\
5745    ? EXPR_LOC_OR_LOC (args[(N)], input_location)	\
5746    : expansion_point_location (arg_loc[(N)]))
5747 
5748 /* Verifies the NARGS arguments ARGS to the builtin function FNDECL.
5749    Returns false if there was an error, otherwise true.  LOC is the
5750    location of the function; ARG_LOC is a vector of locations of the
5751    arguments.  */
5752 
5753 bool
5754 check_builtin_function_arguments (location_t loc, vec<location_t> arg_loc,
5755 				  tree fndecl, int nargs, tree *args)
5756 {
5757   if (!DECL_BUILT_IN (fndecl)
5758       || DECL_BUILT_IN_CLASS (fndecl) != BUILT_IN_NORMAL)
5759     return true;
5760 
5761   switch (DECL_FUNCTION_CODE (fndecl))
5762     {
5763     case BUILT_IN_ALLOCA_WITH_ALIGN_AND_MAX:
5764       if (!tree_fits_uhwi_p (args[2]))
5765 	{
5766 	  error_at (ARG_LOCATION (2),
5767 		    "third argument to function %qE must be a constant integer",
5768 		    fndecl);
5769 	  return false;
5770 	}
5771       /* fall through */
5772 
5773     case BUILT_IN_ALLOCA_WITH_ALIGN:
5774       {
5775 	/* Get the requested alignment (in bits) if it's a constant
5776 	   integer expression.  */
5777 	unsigned HOST_WIDE_INT align
5778 	  = tree_fits_uhwi_p (args[1]) ? tree_to_uhwi (args[1]) : 0;
5779 
5780 	/* Determine if the requested alignment is a power of 2.  */
5781 	if ((align & (align - 1)))
5782 	  align = 0;
5783 
5784 	/* The maximum alignment in bits corresponding to the same
5785 	   maximum in bytes enforced in check_user_alignment().  */
5786 	unsigned maxalign = (UINT_MAX >> 1) + 1;
5787 
5788 	/* Reject invalid alignments.  */
5789 	if (align < BITS_PER_UNIT || maxalign < align)
5790 	  {
5791 	    error_at (ARG_LOCATION (1),
5792 		      "second argument to function %qE must be a constant "
5793 		      "integer power of 2 between %qi and %qu bits",
5794 		      fndecl, BITS_PER_UNIT, maxalign);
5795 	    return false;
5796 	  }
5797 	return true;
5798       }
5799 
5800     case BUILT_IN_CONSTANT_P:
5801       return builtin_function_validate_nargs (loc, fndecl, nargs, 1);
5802 
5803     case BUILT_IN_ISFINITE:
5804     case BUILT_IN_ISINF:
5805     case BUILT_IN_ISINF_SIGN:
5806     case BUILT_IN_ISNAN:
5807     case BUILT_IN_ISNORMAL:
5808     case BUILT_IN_SIGNBIT:
5809       if (builtin_function_validate_nargs (loc, fndecl, nargs, 1))
5810 	{
5811 	  if (TREE_CODE (TREE_TYPE (args[0])) != REAL_TYPE)
5812 	    {
5813 	      error_at (ARG_LOCATION (0), "non-floating-point argument in "
5814 			"call to function %qE", fndecl);
5815 	      return false;
5816 	    }
5817 	  return true;
5818 	}
5819       return false;
5820 
5821     case BUILT_IN_ISGREATER:
5822     case BUILT_IN_ISGREATEREQUAL:
5823     case BUILT_IN_ISLESS:
5824     case BUILT_IN_ISLESSEQUAL:
5825     case BUILT_IN_ISLESSGREATER:
5826     case BUILT_IN_ISUNORDERED:
5827       if (builtin_function_validate_nargs (loc, fndecl, nargs, 2))
5828 	{
5829 	  enum tree_code code0, code1;
5830 	  code0 = TREE_CODE (TREE_TYPE (args[0]));
5831 	  code1 = TREE_CODE (TREE_TYPE (args[1]));
5832 	  if (!((code0 == REAL_TYPE && code1 == REAL_TYPE)
5833 		|| (code0 == REAL_TYPE && code1 == INTEGER_TYPE)
5834 		|| (code0 == INTEGER_TYPE && code1 == REAL_TYPE)))
5835 	    {
5836 	      error_at (loc, "non-floating-point arguments in call to "
5837 			"function %qE", fndecl);
5838 	      return false;
5839 	    }
5840 	  return true;
5841 	}
5842       return false;
5843 
5844     case BUILT_IN_FPCLASSIFY:
5845       if (builtin_function_validate_nargs (loc, fndecl, nargs, 6))
5846 	{
5847 	  for (unsigned int i = 0; i < 5; i++)
5848 	    if (TREE_CODE (args[i]) != INTEGER_CST)
5849 	      {
5850 		error_at (ARG_LOCATION (i), "non-const integer argument %u in "
5851 			  "call to function %qE", i + 1, fndecl);
5852 		return false;
5853 	      }
5854 
5855 	  if (TREE_CODE (TREE_TYPE (args[5])) != REAL_TYPE)
5856 	    {
5857 	      error_at (ARG_LOCATION (5), "non-floating-point argument in "
5858 			"call to function %qE", fndecl);
5859 	      return false;
5860 	    }
5861 	  return true;
5862 	}
5863       return false;
5864 
5865     case BUILT_IN_ASSUME_ALIGNED:
5866       if (builtin_function_validate_nargs (loc, fndecl, nargs, 2 + (nargs > 2)))
5867 	{
5868 	  if (nargs >= 3 && TREE_CODE (TREE_TYPE (args[2])) != INTEGER_TYPE)
5869 	    {
5870 	      error_at (ARG_LOCATION (2), "non-integer argument 3 in call to "
5871 			"function %qE", fndecl);
5872 	      return false;
5873 	    }
5874 	  return true;
5875 	}
5876       return false;
5877 
5878     case BUILT_IN_ADD_OVERFLOW:
5879     case BUILT_IN_SUB_OVERFLOW:
5880     case BUILT_IN_MUL_OVERFLOW:
5881       if (builtin_function_validate_nargs (loc, fndecl, nargs, 3))
5882 	{
5883 	  unsigned i;
5884 	  for (i = 0; i < 2; i++)
5885 	    if (!INTEGRAL_TYPE_P (TREE_TYPE (args[i])))
5886 	      {
5887 		error_at (ARG_LOCATION (i), "argument %u in call to function "
5888 			  "%qE does not have integral type", i + 1, fndecl);
5889 		return false;
5890 	      }
5891 	  if (TREE_CODE (TREE_TYPE (args[2])) != POINTER_TYPE
5892 	      || !INTEGRAL_TYPE_P (TREE_TYPE (TREE_TYPE (args[2]))))
5893 	    {
5894 	      error_at (ARG_LOCATION (2), "argument 3 in call to function %qE "
5895 			"does not have pointer to integral type", fndecl);
5896 	      return false;
5897 	    }
5898 	  else if (TREE_CODE (TREE_TYPE (TREE_TYPE (args[2]))) == ENUMERAL_TYPE)
5899 	    {
5900 	      error_at (ARG_LOCATION (2), "argument 3 in call to function %qE "
5901 			"has pointer to enumerated type", fndecl);
5902 	      return false;
5903 	    }
5904 	  else if (TREE_CODE (TREE_TYPE (TREE_TYPE (args[2]))) == BOOLEAN_TYPE)
5905 	    {
5906 	      error_at (ARG_LOCATION (2), "argument 3 in call to function %qE "
5907 			"has pointer to boolean type", fndecl);
5908 	      return false;
5909 	    }
5910 	  return true;
5911 	}
5912       return false;
5913 
5914     case BUILT_IN_ADD_OVERFLOW_P:
5915     case BUILT_IN_SUB_OVERFLOW_P:
5916     case BUILT_IN_MUL_OVERFLOW_P:
5917       if (builtin_function_validate_nargs (loc, fndecl, nargs, 3))
5918 	{
5919 	  unsigned i;
5920 	  for (i = 0; i < 3; i++)
5921 	    if (!INTEGRAL_TYPE_P (TREE_TYPE (args[i])))
5922 	      {
5923 		error_at (ARG_LOCATION (i), "argument %u in call to function "
5924 			  "%qE does not have integral type", i + 1, fndecl);
5925 		return false;
5926 	      }
5927 	  if (TREE_CODE (TREE_TYPE (args[2])) == ENUMERAL_TYPE)
5928 	    {
5929 	      error_at (ARG_LOCATION (2), "argument 3 in call to function "
5930 			"%qE has enumerated type", fndecl);
5931 	      return false;
5932 	    }
5933 	  else if (TREE_CODE (TREE_TYPE (args[2])) == BOOLEAN_TYPE)
5934 	    {
5935 	      error_at (ARG_LOCATION (2), "argument 3 in call to function "
5936 			"%qE has boolean type", fndecl);
5937 	      return false;
5938 	    }
5939 	  return true;
5940 	}
5941       return false;
5942 
5943     default:
5944       return true;
5945     }
5946 }
5947 
5948 /* Subroutine of c_parse_error.
5949    Return the result of concatenating LHS and RHS. RHS is really
5950    a string literal, its first character is indicated by RHS_START and
5951    RHS_SIZE is its length (including the terminating NUL character).
5952 
5953    The caller is responsible for deleting the returned pointer.  */
5954 
5955 static char *
5956 catenate_strings (const char *lhs, const char *rhs_start, int rhs_size)
5957 {
5958   const size_t lhs_size = strlen (lhs);
5959   char *result = XNEWVEC (char, lhs_size + rhs_size);
5960   memcpy (result, lhs, lhs_size);
5961   memcpy (result + lhs_size, rhs_start, rhs_size);
5962   return result;
5963 }
5964 
5965 /* Issue the error given by GMSGID at RICHLOC, indicating that it occurred
5966    before TOKEN, which had the associated VALUE.  */
5967 
5968 void
5969 c_parse_error (const char *gmsgid, enum cpp_ttype token_type,
5970 	       tree value, unsigned char token_flags,
5971 	       rich_location *richloc)
5972 {
5973 #define catenate_messages(M1, M2) catenate_strings ((M1), (M2), sizeof (M2))
5974 
5975   char *message = NULL;
5976 
5977   if (token_type == CPP_EOF)
5978     message = catenate_messages (gmsgid, " at end of input");
5979   else if (token_type == CPP_CHAR
5980 	   || token_type == CPP_WCHAR
5981 	   || token_type == CPP_CHAR16
5982 	   || token_type == CPP_CHAR32
5983 	   || token_type == CPP_UTF8CHAR)
5984     {
5985       unsigned int val = TREE_INT_CST_LOW (value);
5986       const char *prefix;
5987 
5988       switch (token_type)
5989 	{
5990 	default:
5991 	  prefix = "";
5992 	  break;
5993 	case CPP_WCHAR:
5994 	  prefix = "L";
5995 	  break;
5996 	case CPP_CHAR16:
5997 	  prefix = "u";
5998 	  break;
5999 	case CPP_CHAR32:
6000 	  prefix = "U";
6001 	  break;
6002 	case CPP_UTF8CHAR:
6003 	  prefix = "u8";
6004 	  break;
6005         }
6006 
6007       if (val <= UCHAR_MAX && ISGRAPH (val))
6008 	message = catenate_messages (gmsgid, " before %s'%c'");
6009       else
6010 	message = catenate_messages (gmsgid, " before %s'\\x%x'");
6011 
6012       error_at (richloc, message, prefix, val);
6013       free (message);
6014       message = NULL;
6015     }
6016   else if (token_type == CPP_CHAR_USERDEF
6017 	   || token_type == CPP_WCHAR_USERDEF
6018 	   || token_type == CPP_CHAR16_USERDEF
6019 	   || token_type == CPP_CHAR32_USERDEF
6020 	   || token_type == CPP_UTF8CHAR_USERDEF)
6021     message = catenate_messages (gmsgid,
6022 				 " before user-defined character literal");
6023   else if (token_type == CPP_STRING_USERDEF
6024 	   || token_type == CPP_WSTRING_USERDEF
6025 	   || token_type == CPP_STRING16_USERDEF
6026 	   || token_type == CPP_STRING32_USERDEF
6027 	   || token_type == CPP_UTF8STRING_USERDEF)
6028     message = catenate_messages (gmsgid, " before user-defined string literal");
6029   else if (token_type == CPP_STRING
6030 	   || token_type == CPP_WSTRING
6031 	   || token_type == CPP_STRING16
6032 	   || token_type == CPP_STRING32
6033 	   || token_type == CPP_UTF8STRING)
6034     message = catenate_messages (gmsgid, " before string constant");
6035   else if (token_type == CPP_NUMBER)
6036     message = catenate_messages (gmsgid, " before numeric constant");
6037   else if (token_type == CPP_NAME)
6038     {
6039       message = catenate_messages (gmsgid, " before %qE");
6040       error_at (richloc, message, value);
6041       free (message);
6042       message = NULL;
6043     }
6044   else if (token_type == CPP_PRAGMA)
6045     message = catenate_messages (gmsgid, " before %<#pragma%>");
6046   else if (token_type == CPP_PRAGMA_EOL)
6047     message = catenate_messages (gmsgid, " before end of line");
6048   else if (token_type == CPP_DECLTYPE)
6049     message = catenate_messages (gmsgid, " before %<decltype%>");
6050   else if (token_type < N_TTYPES)
6051     {
6052       message = catenate_messages (gmsgid, " before %qs token");
6053       error_at (richloc, message, cpp_type2name (token_type, token_flags));
6054       free (message);
6055       message = NULL;
6056     }
6057   else
6058     error_at (richloc, gmsgid);
6059 
6060   if (message)
6061     {
6062       error_at (richloc, message);
6063       free (message);
6064     }
6065 #undef catenate_messages
6066 }
6067 
6068 /* Return the gcc option code associated with the reason for a cpp
6069    message, or 0 if none.  */
6070 
6071 static int
6072 c_option_controlling_cpp_error (int reason)
6073 {
6074   const struct cpp_reason_option_codes_t *entry;
6075 
6076   for (entry = cpp_reason_option_codes; entry->reason != CPP_W_NONE; entry++)
6077     {
6078       if (entry->reason == reason)
6079 	return entry->option_code;
6080     }
6081   return 0;
6082 }
6083 
6084 /* Callback from cpp_error for PFILE to print diagnostics from the
6085    preprocessor.  The diagnostic is of type LEVEL, with REASON set
6086    to the reason code if LEVEL is represents a warning, at location
6087    RICHLOC unless this is after lexing and the compiler's location
6088    should be used instead; MSG is the translated message and AP
6089    the arguments.  Returns true if a diagnostic was emitted, false
6090    otherwise.  */
6091 
6092 bool
6093 c_cpp_error (cpp_reader *pfile ATTRIBUTE_UNUSED, int level, int reason,
6094 	     rich_location *richloc,
6095 	     const char *msg, va_list *ap)
6096 {
6097   diagnostic_info diagnostic;
6098   diagnostic_t dlevel;
6099   bool save_warn_system_headers = global_dc->dc_warn_system_headers;
6100   bool ret;
6101 
6102   switch (level)
6103     {
6104     case CPP_DL_WARNING_SYSHDR:
6105       if (flag_no_output)
6106 	return false;
6107       global_dc->dc_warn_system_headers = 1;
6108       /* Fall through.  */
6109     case CPP_DL_WARNING:
6110       if (flag_no_output)
6111 	return false;
6112       dlevel = DK_WARNING;
6113       break;
6114     case CPP_DL_PEDWARN:
6115       if (flag_no_output && !flag_pedantic_errors)
6116 	return false;
6117       dlevel = DK_PEDWARN;
6118       break;
6119     case CPP_DL_ERROR:
6120       dlevel = DK_ERROR;
6121       break;
6122     case CPP_DL_ICE:
6123       dlevel = DK_ICE;
6124       break;
6125     case CPP_DL_NOTE:
6126       dlevel = DK_NOTE;
6127       break;
6128     case CPP_DL_FATAL:
6129       dlevel = DK_FATAL;
6130       break;
6131     default:
6132       gcc_unreachable ();
6133     }
6134   if (done_lexing)
6135     richloc->set_range (line_table, 0, input_location, true);
6136   diagnostic_set_info_translated (&diagnostic, msg, ap,
6137 				  richloc, dlevel);
6138   diagnostic_override_option_index (&diagnostic,
6139                                     c_option_controlling_cpp_error (reason));
6140   ret = diagnostic_report_diagnostic (global_dc, &diagnostic);
6141   if (level == CPP_DL_WARNING_SYSHDR)
6142     global_dc->dc_warn_system_headers = save_warn_system_headers;
6143   return ret;
6144 }
6145 
6146 /* Convert a character from the host to the target execution character
6147    set.  cpplib handles this, mostly.  */
6148 
6149 HOST_WIDE_INT
6150 c_common_to_target_charset (HOST_WIDE_INT c)
6151 {
6152   /* Character constants in GCC proper are sign-extended under -fsigned-char,
6153      zero-extended under -fno-signed-char.  cpplib insists that characters
6154      and character constants are always unsigned.  Hence we must convert
6155      back and forth.  */
6156   cppchar_t uc = ((cppchar_t)c) & ((((cppchar_t)1) << CHAR_BIT)-1);
6157 
6158   uc = cpp_host_to_exec_charset (parse_in, uc);
6159 
6160   if (flag_signed_char)
6161     return ((HOST_WIDE_INT)uc) << (HOST_BITS_PER_WIDE_INT - CHAR_TYPE_SIZE)
6162 			       >> (HOST_BITS_PER_WIDE_INT - CHAR_TYPE_SIZE);
6163   else
6164     return uc;
6165 }
6166 
6167 /* Fold an offsetof-like expression.  EXPR is a nested sequence of component
6168    references with an INDIRECT_REF of a constant at the bottom; much like the
6169    traditional rendering of offsetof as a macro.  TYPE is the desired type of
6170    the whole expression.  Return the folded result.  */
6171 
6172 tree
6173 fold_offsetof (tree expr, tree type, enum tree_code ctx)
6174 {
6175   tree base, off, t;
6176   tree_code code = TREE_CODE (expr);
6177   switch (code)
6178     {
6179     case ERROR_MARK:
6180       return expr;
6181 
6182     case VAR_DECL:
6183       error ("cannot apply %<offsetof%> to static data member %qD", expr);
6184       return error_mark_node;
6185 
6186     case CALL_EXPR:
6187     case TARGET_EXPR:
6188       error ("cannot apply %<offsetof%> when %<operator[]%> is overloaded");
6189       return error_mark_node;
6190 
6191     case NOP_EXPR:
6192     case INDIRECT_REF:
6193       if (!TREE_CONSTANT (TREE_OPERAND (expr, 0)))
6194 	{
6195 	  error ("cannot apply %<offsetof%> to a non constant address");
6196 	  return error_mark_node;
6197 	}
6198       return convert (type, TREE_OPERAND (expr, 0));
6199 
6200     case COMPONENT_REF:
6201       base = fold_offsetof (TREE_OPERAND (expr, 0), type, code);
6202       if (base == error_mark_node)
6203 	return base;
6204 
6205       t = TREE_OPERAND (expr, 1);
6206       if (DECL_C_BIT_FIELD (t))
6207 	{
6208 	  error ("attempt to take address of bit-field structure "
6209 		 "member %qD", t);
6210 	  return error_mark_node;
6211 	}
6212       off = size_binop_loc (input_location, PLUS_EXPR, DECL_FIELD_OFFSET (t),
6213 			    size_int (tree_to_uhwi (DECL_FIELD_BIT_OFFSET (t))
6214 				      / BITS_PER_UNIT));
6215       break;
6216 
6217     case ARRAY_REF:
6218       base = fold_offsetof (TREE_OPERAND (expr, 0), type, code);
6219       if (base == error_mark_node)
6220 	return base;
6221 
6222       t = TREE_OPERAND (expr, 1);
6223 
6224       /* Check if the offset goes beyond the upper bound of the array.  */
6225       if (TREE_CODE (t) == INTEGER_CST && tree_int_cst_sgn (t) >= 0)
6226 	{
6227 	  tree upbound = array_ref_up_bound (expr);
6228 	  if (upbound != NULL_TREE
6229 	      && TREE_CODE (upbound) == INTEGER_CST
6230 	      && !tree_int_cst_equal (upbound,
6231 				      TYPE_MAX_VALUE (TREE_TYPE (upbound))))
6232 	    {
6233 	      if (ctx != ARRAY_REF && ctx != COMPONENT_REF)
6234 	        upbound = size_binop (PLUS_EXPR, upbound,
6235 				      build_int_cst (TREE_TYPE (upbound), 1));
6236 	      if (tree_int_cst_lt (upbound, t))
6237 		{
6238 		  tree v;
6239 
6240 		  for (v = TREE_OPERAND (expr, 0);
6241 		       TREE_CODE (v) == COMPONENT_REF;
6242 		       v = TREE_OPERAND (v, 0))
6243 		    if (TREE_CODE (TREE_TYPE (TREE_OPERAND (v, 0)))
6244 			== RECORD_TYPE)
6245 		      {
6246 			tree fld_chain = DECL_CHAIN (TREE_OPERAND (v, 1));
6247 			for (; fld_chain; fld_chain = DECL_CHAIN (fld_chain))
6248 			  if (TREE_CODE (fld_chain) == FIELD_DECL)
6249 			    break;
6250 
6251 			if (fld_chain)
6252 			  break;
6253 		      }
6254 		  /* Don't warn if the array might be considered a poor
6255 		     man's flexible array member with a very permissive
6256 		     definition thereof.  */
6257 		  if (TREE_CODE (v) == ARRAY_REF
6258 		      || TREE_CODE (v) == COMPONENT_REF)
6259 		    warning (OPT_Warray_bounds,
6260 			     "index %E denotes an offset "
6261 			     "greater than size of %qT",
6262 			     t, TREE_TYPE (TREE_OPERAND (expr, 0)));
6263 		}
6264 	    }
6265 	}
6266 
6267       t = convert (sizetype, t);
6268       off = size_binop (MULT_EXPR, TYPE_SIZE_UNIT (TREE_TYPE (expr)), t);
6269       break;
6270 
6271     case COMPOUND_EXPR:
6272       /* Handle static members of volatile structs.  */
6273       t = TREE_OPERAND (expr, 1);
6274       gcc_checking_assert (VAR_P (get_base_address (t)));
6275       return fold_offsetof (t, type);
6276 
6277     default:
6278       gcc_unreachable ();
6279     }
6280 
6281   if (!POINTER_TYPE_P (type))
6282     return size_binop (PLUS_EXPR, base, convert (type, off));
6283   return fold_build_pointer_plus (base, off);
6284 }
6285 
6286 /* *PTYPE is an incomplete array.  Complete it with a domain based on
6287    INITIAL_VALUE.  If INITIAL_VALUE is not present, use 1 if DO_DEFAULT
6288    is true.  Return 0 if successful, 1 if INITIAL_VALUE can't be deciphered,
6289    2 if INITIAL_VALUE was NULL, and 3 if INITIAL_VALUE was empty.  */
6290 
6291 int
6292 complete_array_type (tree *ptype, tree initial_value, bool do_default)
6293 {
6294   tree maxindex, type, main_type, elt, unqual_elt;
6295   int failure = 0, quals;
6296   bool overflow_p = false;
6297 
6298   maxindex = size_zero_node;
6299   if (initial_value)
6300     {
6301       if (TREE_CODE (initial_value) == STRING_CST)
6302 	{
6303 	  int eltsize
6304 	    = int_size_in_bytes (TREE_TYPE (TREE_TYPE (initial_value)));
6305 	  maxindex = size_int (TREE_STRING_LENGTH (initial_value)/eltsize - 1);
6306 	}
6307       else if (TREE_CODE (initial_value) == CONSTRUCTOR)
6308 	{
6309 	  vec<constructor_elt, va_gc> *v = CONSTRUCTOR_ELTS (initial_value);
6310 
6311 	  if (vec_safe_is_empty (v))
6312 	    {
6313 	      if (pedantic)
6314 		failure = 3;
6315 	      maxindex = ssize_int (-1);
6316 	    }
6317 	  else
6318 	    {
6319 	      tree curindex;
6320 	      unsigned HOST_WIDE_INT cnt;
6321 	      constructor_elt *ce;
6322 	      bool fold_p = false;
6323 
6324 	      if ((*v)[0].index)
6325 		maxindex = (*v)[0].index, fold_p = true;
6326 
6327 	      curindex = maxindex;
6328 
6329 	      for (cnt = 1; vec_safe_iterate (v, cnt, &ce); cnt++)
6330 		{
6331 		  bool curfold_p = false;
6332 		  if (ce->index)
6333 		    curindex = ce->index, curfold_p = true;
6334 		  else
6335 		    {
6336 		      if (fold_p)
6337 			{
6338 			  /* Since we treat size types now as ordinary
6339 			     unsigned types, we need an explicit overflow
6340 			     check.  */
6341 			  tree orig = curindex;
6342 		          curindex = fold_convert (sizetype, curindex);
6343 			  overflow_p |= tree_int_cst_lt (curindex, orig);
6344 			}
6345 		      curindex = size_binop (PLUS_EXPR, curindex,
6346 					     size_one_node);
6347 		    }
6348 		  if (tree_int_cst_lt (maxindex, curindex))
6349 		    maxindex = curindex, fold_p = curfold_p;
6350 		}
6351 	      if (fold_p)
6352 		{
6353 		  tree orig = maxindex;
6354 	          maxindex = fold_convert (sizetype, maxindex);
6355 		  overflow_p |= tree_int_cst_lt (maxindex, orig);
6356 		}
6357 	    }
6358 	}
6359       else
6360 	{
6361 	  /* Make an error message unless that happened already.  */
6362 	  if (initial_value != error_mark_node)
6363 	    failure = 1;
6364 	}
6365     }
6366   else
6367     {
6368       failure = 2;
6369       if (!do_default)
6370 	return failure;
6371     }
6372 
6373   type = *ptype;
6374   elt = TREE_TYPE (type);
6375   quals = TYPE_QUALS (strip_array_types (elt));
6376   if (quals == 0)
6377     unqual_elt = elt;
6378   else
6379     unqual_elt = c_build_qualified_type (elt, KEEP_QUAL_ADDR_SPACE (quals));
6380 
6381   /* Using build_distinct_type_copy and modifying things afterward instead
6382      of using build_array_type to create a new type preserves all of the
6383      TYPE_LANG_FLAG_? bits that the front end may have set.  */
6384   main_type = build_distinct_type_copy (TYPE_MAIN_VARIANT (type));
6385   TREE_TYPE (main_type) = unqual_elt;
6386   TYPE_DOMAIN (main_type)
6387     = build_range_type (TREE_TYPE (maxindex),
6388 			build_int_cst (TREE_TYPE (maxindex), 0), maxindex);
6389   TYPE_TYPELESS_STORAGE (main_type) = TYPE_TYPELESS_STORAGE (type);
6390   layout_type (main_type);
6391 
6392   /* Make sure we have the canonical MAIN_TYPE. */
6393   hashval_t hashcode = type_hash_canon_hash (main_type);
6394   main_type = type_hash_canon (hashcode, main_type);
6395 
6396   /* Fix the canonical type.  */
6397   if (TYPE_STRUCTURAL_EQUALITY_P (TREE_TYPE (main_type))
6398       || TYPE_STRUCTURAL_EQUALITY_P (TYPE_DOMAIN (main_type)))
6399     SET_TYPE_STRUCTURAL_EQUALITY (main_type);
6400   else if (TYPE_CANONICAL (TREE_TYPE (main_type)) != TREE_TYPE (main_type)
6401 	   || (TYPE_CANONICAL (TYPE_DOMAIN (main_type))
6402 	       != TYPE_DOMAIN (main_type)))
6403     TYPE_CANONICAL (main_type)
6404       = build_array_type (TYPE_CANONICAL (TREE_TYPE (main_type)),
6405 			  TYPE_CANONICAL (TYPE_DOMAIN (main_type)),
6406 			  TYPE_TYPELESS_STORAGE (main_type));
6407   else
6408     TYPE_CANONICAL (main_type) = main_type;
6409 
6410   if (quals == 0)
6411     type = main_type;
6412   else
6413     type = c_build_qualified_type (main_type, quals);
6414 
6415   if (COMPLETE_TYPE_P (type)
6416       && TREE_CODE (TYPE_SIZE_UNIT (type)) == INTEGER_CST
6417       && (overflow_p || TREE_OVERFLOW (TYPE_SIZE_UNIT (type))))
6418     {
6419       error ("size of array is too large");
6420       /* If we proceed with the array type as it is, we'll eventually
6421 	 crash in tree_to_[su]hwi().  */
6422       type = error_mark_node;
6423     }
6424 
6425   *ptype = type;
6426   return failure;
6427 }
6428 
6429 /* Like c_mark_addressable but don't check register qualifier.  */
6430 void
6431 c_common_mark_addressable_vec (tree t)
6432 {
6433   if (TREE_CODE (t) == C_MAYBE_CONST_EXPR)
6434     t = C_MAYBE_CONST_EXPR_EXPR (t);
6435   while (handled_component_p (t))
6436     t = TREE_OPERAND (t, 0);
6437   if (!VAR_P (t)
6438       && TREE_CODE (t) != PARM_DECL
6439       && TREE_CODE (t) != COMPOUND_LITERAL_EXPR)
6440     return;
6441   if (!VAR_P (t) || !DECL_HARD_REGISTER (t))
6442     TREE_ADDRESSABLE (t) = 1;
6443 }
6444 
6445 
6446 
6447 /* Used to help initialize the builtin-types.def table.  When a type of
6448    the correct size doesn't exist, use error_mark_node instead of NULL.
6449    The later results in segfaults even when a decl using the type doesn't
6450    get invoked.  */
6451 
6452 tree
6453 builtin_type_for_size (int size, bool unsignedp)
6454 {
6455   tree type = c_common_type_for_size (size, unsignedp);
6456   return type ? type : error_mark_node;
6457 }
6458 
6459 /* A helper function for resolve_overloaded_builtin in resolving the
6460    overloaded __sync_ builtins.  Returns a positive power of 2 if the
6461    first operand of PARAMS is a pointer to a supported data type.
6462    Returns 0 if an error is encountered.
6463    FETCH is true when FUNCTION is one of the _FETCH_OP_ or _OP_FETCH_
6464    built-ins.  */
6465 
6466 static int
6467 sync_resolve_size (tree function, vec<tree, va_gc> *params, bool fetch)
6468 {
6469   /* Type of the argument.  */
6470   tree argtype;
6471   /* Type the argument points to.  */
6472   tree type;
6473   int size;
6474 
6475   if (vec_safe_is_empty (params))
6476     {
6477       error ("too few arguments to function %qE", function);
6478       return 0;
6479     }
6480 
6481   argtype = type = TREE_TYPE ((*params)[0]);
6482   if (TREE_CODE (type) == ARRAY_TYPE && c_dialect_cxx ())
6483     {
6484       /* Force array-to-pointer decay for C++.  */
6485       (*params)[0] = default_conversion ((*params)[0]);
6486       type = TREE_TYPE ((*params)[0]);
6487     }
6488   if (TREE_CODE (type) != POINTER_TYPE)
6489     goto incompatible;
6490 
6491   type = TREE_TYPE (type);
6492   if (!INTEGRAL_TYPE_P (type) && !POINTER_TYPE_P (type))
6493     goto incompatible;
6494 
6495   if (!COMPLETE_TYPE_P (type))
6496     goto incompatible;
6497 
6498   if (fetch && TREE_CODE (type) == BOOLEAN_TYPE)
6499     goto incompatible;
6500 
6501   size = tree_to_uhwi (TYPE_SIZE_UNIT (type));
6502   if (size == 1 || size == 2 || size == 4 || size == 8 || size == 16)
6503     return size;
6504 
6505  incompatible:
6506   /* Issue the diagnostic only if the argument is valid, otherwise
6507      it would be redundant at best and could be misleading.  */
6508   if (argtype != error_mark_node)
6509     error ("operand type %qT is incompatible with argument %d of %qE",
6510 	   argtype, 1, function);
6511   return 0;
6512 }
6513 
6514 /* A helper function for resolve_overloaded_builtin.  Adds casts to
6515    PARAMS to make arguments match up with those of FUNCTION.  Drops
6516    the variadic arguments at the end.  Returns false if some error
6517    was encountered; true on success.  */
6518 
6519 static bool
6520 sync_resolve_params (location_t loc, tree orig_function, tree function,
6521 		     vec<tree, va_gc> *params, bool orig_format)
6522 {
6523   function_args_iterator iter;
6524   tree ptype;
6525   unsigned int parmnum;
6526 
6527   function_args_iter_init (&iter, TREE_TYPE (function));
6528   /* We've declared the implementation functions to use "volatile void *"
6529      as the pointer parameter, so we shouldn't get any complaints from the
6530      call to check_function_arguments what ever type the user used.  */
6531   function_args_iter_next (&iter);
6532   ptype = TREE_TYPE (TREE_TYPE ((*params)[0]));
6533   ptype = TYPE_MAIN_VARIANT (ptype);
6534 
6535   /* For the rest of the values, we need to cast these to FTYPE, so that we
6536      don't get warnings for passing pointer types, etc.  */
6537   parmnum = 0;
6538   while (1)
6539     {
6540       tree val, arg_type;
6541 
6542       arg_type = function_args_iter_cond (&iter);
6543       /* XXX void_type_node belies the abstraction.  */
6544       if (arg_type == void_type_node)
6545 	break;
6546 
6547       ++parmnum;
6548       if (params->length () <= parmnum)
6549 	{
6550 	  error_at (loc, "too few arguments to function %qE", orig_function);
6551 	  return false;
6552 	}
6553 
6554       /* Only convert parameters if arg_type is unsigned integer type with
6555 	 new format sync routines, i.e. don't attempt to convert pointer
6556 	 arguments (e.g. EXPECTED argument of __atomic_compare_exchange_n),
6557 	 bool arguments (e.g. WEAK argument) or signed int arguments (memmodel
6558 	 kinds).  */
6559       if (TREE_CODE (arg_type) == INTEGER_TYPE && TYPE_UNSIGNED (arg_type))
6560 	{
6561 	  /* Ideally for the first conversion we'd use convert_for_assignment
6562 	     so that we get warnings for anything that doesn't match the pointer
6563 	     type.  This isn't portable across the C and C++ front ends atm.  */
6564 	  val = (*params)[parmnum];
6565 	  val = convert (ptype, val);
6566 	  val = convert (arg_type, val);
6567 	  (*params)[parmnum] = val;
6568 	}
6569 
6570       function_args_iter_next (&iter);
6571     }
6572 
6573   /* __atomic routines are not variadic.  */
6574   if (!orig_format && params->length () != parmnum + 1)
6575     {
6576       error_at (loc, "too many arguments to function %qE", orig_function);
6577       return false;
6578     }
6579 
6580   /* The definition of these primitives is variadic, with the remaining
6581      being "an optional list of variables protected by the memory barrier".
6582      No clue what that's supposed to mean, precisely, but we consider all
6583      call-clobbered variables to be protected so we're safe.  */
6584   params->truncate (parmnum + 1);
6585 
6586   return true;
6587 }
6588 
6589 /* A helper function for resolve_overloaded_builtin.  Adds a cast to
6590    RESULT to make it match the type of the first pointer argument in
6591    PARAMS.  */
6592 
6593 static tree
6594 sync_resolve_return (tree first_param, tree result, bool orig_format)
6595 {
6596   tree ptype = TREE_TYPE (TREE_TYPE (first_param));
6597   tree rtype = TREE_TYPE (result);
6598   ptype = TYPE_MAIN_VARIANT (ptype);
6599 
6600   /* New format doesn't require casting unless the types are the same size.  */
6601   if (orig_format || tree_int_cst_equal (TYPE_SIZE (ptype), TYPE_SIZE (rtype)))
6602     return convert (ptype, result);
6603   else
6604     return result;
6605 }
6606 
6607 /* This function verifies the PARAMS to generic atomic FUNCTION.
6608    It returns the size if all the parameters are the same size, otherwise
6609    0 is returned if the parameters are invalid.  */
6610 
6611 static int
6612 get_atomic_generic_size (location_t loc, tree function,
6613 			 vec<tree, va_gc> *params)
6614 {
6615   unsigned int n_param;
6616   unsigned int n_model;
6617   unsigned int x;
6618   int size_0;
6619   tree type_0;
6620 
6621   /* Determine the parameter makeup.  */
6622   switch (DECL_FUNCTION_CODE (function))
6623     {
6624     case BUILT_IN_ATOMIC_EXCHANGE:
6625       n_param = 4;
6626       n_model = 1;
6627       break;
6628     case BUILT_IN_ATOMIC_LOAD:
6629     case BUILT_IN_ATOMIC_STORE:
6630       n_param = 3;
6631       n_model = 1;
6632       break;
6633     case BUILT_IN_ATOMIC_COMPARE_EXCHANGE:
6634       n_param = 6;
6635       n_model = 2;
6636       break;
6637     default:
6638       gcc_unreachable ();
6639     }
6640 
6641   if (vec_safe_length (params) != n_param)
6642     {
6643       error_at (loc, "incorrect number of arguments to function %qE", function);
6644       return 0;
6645     }
6646 
6647   /* Get type of first parameter, and determine its size.  */
6648   type_0 = TREE_TYPE ((*params)[0]);
6649   if (TREE_CODE (type_0) == ARRAY_TYPE && c_dialect_cxx ())
6650     {
6651       /* Force array-to-pointer decay for C++.  */
6652       (*params)[0] = default_conversion ((*params)[0]);
6653       type_0 = TREE_TYPE ((*params)[0]);
6654     }
6655   if (TREE_CODE (type_0) != POINTER_TYPE || VOID_TYPE_P (TREE_TYPE (type_0)))
6656     {
6657       error_at (loc, "argument 1 of %qE must be a non-void pointer type",
6658 		function);
6659       return 0;
6660     }
6661 
6662   /* Types must be compile time constant sizes. */
6663   if (TREE_CODE ((TYPE_SIZE_UNIT (TREE_TYPE (type_0)))) != INTEGER_CST)
6664     {
6665       error_at (loc,
6666 		"argument 1 of %qE must be a pointer to a constant size type",
6667 		function);
6668       return 0;
6669     }
6670 
6671   size_0 = tree_to_uhwi (TYPE_SIZE_UNIT (TREE_TYPE (type_0)));
6672 
6673   /* Zero size objects are not allowed.  */
6674   if (size_0 == 0)
6675     {
6676       error_at (loc,
6677 		"argument 1 of %qE must be a pointer to a nonzero size object",
6678 		function);
6679       return 0;
6680     }
6681 
6682   /* Check each other parameter is a pointer and the same size.  */
6683   for (x = 0; x < n_param - n_model; x++)
6684     {
6685       int size;
6686       tree type = TREE_TYPE ((*params)[x]);
6687       /* __atomic_compare_exchange has a bool in the 4th position, skip it.  */
6688       if (n_param == 6 && x == 3)
6689         continue;
6690       if (TREE_CODE (type) == ARRAY_TYPE && c_dialect_cxx ())
6691 	{
6692 	  /* Force array-to-pointer decay for C++.  */
6693 	  (*params)[x] = default_conversion ((*params)[x]);
6694 	  type = TREE_TYPE ((*params)[x]);
6695 	}
6696       if (!POINTER_TYPE_P (type))
6697 	{
6698 	  error_at (loc, "argument %d of %qE must be a pointer type", x + 1,
6699 		    function);
6700 	  return 0;
6701 	}
6702       else if (TYPE_SIZE_UNIT (TREE_TYPE (type))
6703 	       && TREE_CODE ((TYPE_SIZE_UNIT (TREE_TYPE (type))))
6704 		  != INTEGER_CST)
6705 	{
6706 	  error_at (loc, "argument %d of %qE must be a pointer to a constant "
6707 		    "size type", x + 1, function);
6708 	  return 0;
6709 	}
6710       else if (FUNCTION_POINTER_TYPE_P (type))
6711 	{
6712 	  error_at (loc, "argument %d of %qE must not be a pointer to a "
6713 		    "function", x + 1, function);
6714 	  return 0;
6715 	}
6716       tree type_size = TYPE_SIZE_UNIT (TREE_TYPE (type));
6717       size = type_size ? tree_to_uhwi (type_size) : 0;
6718       if (size != size_0)
6719 	{
6720 	  error_at (loc, "size mismatch in argument %d of %qE", x + 1,
6721 		    function);
6722 	  return 0;
6723 	}
6724     }
6725 
6726   /* Check memory model parameters for validity.  */
6727   for (x = n_param - n_model ; x < n_param; x++)
6728     {
6729       tree p = (*params)[x];
6730       if (!INTEGRAL_TYPE_P (TREE_TYPE (p)))
6731 	{
6732 	  error_at (loc, "non-integer memory model argument %d of %qE", x + 1,
6733 		    function);
6734 	  return 0;
6735 	}
6736       p = fold_for_warn (p);
6737       if (TREE_CODE (p) == INTEGER_CST)
6738 	{
6739 	  /* memmodel_base masks the low 16 bits, thus ignore any bits above
6740 	     it by using TREE_INT_CST_LOW instead of tree_to_*hwi.  Those high
6741 	     bits will be checked later during expansion in target specific
6742 	     way.  */
6743 	  if (memmodel_base (TREE_INT_CST_LOW (p)) >= MEMMODEL_LAST)
6744 	    warning_at (loc, OPT_Winvalid_memory_model,
6745 			"invalid memory model argument %d of %qE", x + 1,
6746 			function);
6747 	}
6748     }
6749 
6750   return size_0;
6751 }
6752 
6753 
6754 /* This will take an __atomic_ generic FUNCTION call, and add a size parameter N
6755    at the beginning of the parameter list PARAMS representing the size of the
6756    objects.  This is to match the library ABI requirement.  LOC is the location
6757    of the function call.
6758    The new function is returned if it needed rebuilding, otherwise NULL_TREE is
6759    returned to allow the external call to be constructed.  */
6760 
6761 static tree
6762 add_atomic_size_parameter (unsigned n, location_t loc, tree function,
6763 			   vec<tree, va_gc> *params)
6764 {
6765   tree size_node;
6766 
6767   /* Insert a SIZE_T parameter as the first param.  If there isn't
6768      enough space, allocate a new vector and recursively re-build with that.  */
6769   if (!params->space (1))
6770     {
6771       unsigned int z, len;
6772       vec<tree, va_gc> *v;
6773       tree f;
6774 
6775       len = params->length ();
6776       vec_alloc (v, len + 1);
6777       v->quick_push (build_int_cst (size_type_node, n));
6778       for (z = 0; z < len; z++)
6779 	v->quick_push ((*params)[z]);
6780       f = build_function_call_vec (loc, vNULL, function, v, NULL);
6781       vec_free (v);
6782       return f;
6783     }
6784 
6785   /* Add the size parameter and leave as a function call for processing.  */
6786   size_node = build_int_cst (size_type_node, n);
6787   params->quick_insert (0, size_node);
6788   return NULL_TREE;
6789 }
6790 
6791 
6792 /* Return whether atomic operations for naturally aligned N-byte
6793    arguments are supported, whether inline or through libatomic.  */
6794 static bool
6795 atomic_size_supported_p (int n)
6796 {
6797   switch (n)
6798     {
6799     case 1:
6800     case 2:
6801     case 4:
6802     case 8:
6803       return true;
6804 
6805     case 16:
6806       return targetm.scalar_mode_supported_p (TImode);
6807 
6808     default:
6809       return false;
6810     }
6811 }
6812 
6813 /* This will process an __atomic_exchange function call, determine whether it
6814    needs to be mapped to the _N variation, or turned into a library call.
6815    LOC is the location of the builtin call.
6816    FUNCTION is the DECL that has been invoked;
6817    PARAMS is the argument list for the call.  The return value is non-null
6818    TRUE is returned if it is translated into the proper format for a call to the
6819    external library, and NEW_RETURN is set the tree for that function.
6820    FALSE is returned if processing for the _N variation is required, and
6821    NEW_RETURN is set to the return value the result is copied into.  */
6822 static bool
6823 resolve_overloaded_atomic_exchange (location_t loc, tree function,
6824 				    vec<tree, va_gc> *params, tree *new_return)
6825 {
6826   tree p0, p1, p2, p3;
6827   tree I_type, I_type_ptr;
6828   int n = get_atomic_generic_size (loc, function, params);
6829 
6830   /* Size of 0 is an error condition.  */
6831   if (n == 0)
6832     {
6833       *new_return = error_mark_node;
6834       return true;
6835     }
6836 
6837   /* If not a lock-free size, change to the library generic format.  */
6838   if (!atomic_size_supported_p (n))
6839     {
6840       *new_return = add_atomic_size_parameter (n, loc, function, params);
6841       return true;
6842     }
6843 
6844   /* Otherwise there is a lockfree match, transform the call from:
6845        void fn(T* mem, T* desired, T* return, model)
6846      into
6847        *return = (T) (fn (In* mem, (In) *desired, model))  */
6848 
6849   p0 = (*params)[0];
6850   p1 = (*params)[1];
6851   p2 = (*params)[2];
6852   p3 = (*params)[3];
6853 
6854   /* Create pointer to appropriate size.  */
6855   I_type = builtin_type_for_size (BITS_PER_UNIT * n, 1);
6856   I_type_ptr = build_pointer_type (I_type);
6857 
6858   /* Convert object pointer to required type.  */
6859   p0 = build1 (VIEW_CONVERT_EXPR, I_type_ptr, p0);
6860   (*params)[0] = p0;
6861   /* Convert new value to required type, and dereference it.  */
6862   p1 = build_indirect_ref (loc, p1, RO_UNARY_STAR);
6863   p1 = build1 (VIEW_CONVERT_EXPR, I_type, p1);
6864   (*params)[1] = p1;
6865 
6866   /* Move memory model to the 3rd position, and end param list.  */
6867   (*params)[2] = p3;
6868   params->truncate (3);
6869 
6870   /* Convert return pointer and dereference it for later assignment.  */
6871   *new_return = build_indirect_ref (loc, p2, RO_UNARY_STAR);
6872 
6873   return false;
6874 }
6875 
6876 
6877 /* This will process an __atomic_compare_exchange function call, determine
6878    whether it needs to be mapped to the _N variation, or turned into a lib call.
6879    LOC is the location of the builtin call.
6880    FUNCTION is the DECL that has been invoked;
6881    PARAMS is the argument list for the call.  The return value is non-null
6882    TRUE is returned if it is translated into the proper format for a call to the
6883    external library, and NEW_RETURN is set the tree for that function.
6884    FALSE is returned if processing for the _N variation is required.  */
6885 
6886 static bool
6887 resolve_overloaded_atomic_compare_exchange (location_t loc, tree function,
6888 					    vec<tree, va_gc> *params,
6889 					    tree *new_return)
6890 {
6891   tree p0, p1, p2;
6892   tree I_type, I_type_ptr;
6893   int n = get_atomic_generic_size (loc, function, params);
6894 
6895   /* Size of 0 is an error condition.  */
6896   if (n == 0)
6897     {
6898       *new_return = error_mark_node;
6899       return true;
6900     }
6901 
6902   /* If not a lock-free size, change to the library generic format.  */
6903   if (!atomic_size_supported_p (n))
6904     {
6905       /* The library generic format does not have the weak parameter, so
6906 	 remove it from the param list.  Since a parameter has been removed,
6907 	 we can be sure that there is room for the SIZE_T parameter, meaning
6908 	 there will not be a recursive rebuilding of the parameter list, so
6909 	 there is no danger this will be done twice.  */
6910       if (n > 0)
6911         {
6912 	  (*params)[3] = (*params)[4];
6913 	  (*params)[4] = (*params)[5];
6914 	  params->truncate (5);
6915 	}
6916       *new_return = add_atomic_size_parameter (n, loc, function, params);
6917       return true;
6918     }
6919 
6920   /* Otherwise, there is a match, so the call needs to be transformed from:
6921        bool fn(T* mem, T* desired, T* return, weak, success, failure)
6922      into
6923        bool fn ((In *)mem, (In *)expected, (In) *desired, weak, succ, fail)  */
6924 
6925   p0 = (*params)[0];
6926   p1 = (*params)[1];
6927   p2 = (*params)[2];
6928 
6929   /* Create pointer to appropriate size.  */
6930   I_type = builtin_type_for_size (BITS_PER_UNIT * n, 1);
6931   I_type_ptr = build_pointer_type (I_type);
6932 
6933   /* Convert object pointer to required type.  */
6934   p0 = build1 (VIEW_CONVERT_EXPR, I_type_ptr, p0);
6935   (*params)[0] = p0;
6936 
6937   /* Convert expected pointer to required type.  */
6938   p1 = build1 (VIEW_CONVERT_EXPR, I_type_ptr, p1);
6939   (*params)[1] = p1;
6940 
6941   /* Convert desired value to required type, and dereference it.  */
6942   p2 = build_indirect_ref (loc, p2, RO_UNARY_STAR);
6943   p2 = build1 (VIEW_CONVERT_EXPR, I_type, p2);
6944   (*params)[2] = p2;
6945 
6946   /* The rest of the parameters are fine. NULL means no special return value
6947      processing.*/
6948   *new_return = NULL;
6949   return false;
6950 }
6951 
6952 
6953 /* This will process an __atomic_load function call, determine whether it
6954    needs to be mapped to the _N variation, or turned into a library call.
6955    LOC is the location of the builtin call.
6956    FUNCTION is the DECL that has been invoked;
6957    PARAMS is the argument list for the call.  The return value is non-null
6958    TRUE is returned if it is translated into the proper format for a call to the
6959    external library, and NEW_RETURN is set the tree for that function.
6960    FALSE is returned if processing for the _N variation is required, and
6961    NEW_RETURN is set to the return value the result is copied into.  */
6962 
6963 static bool
6964 resolve_overloaded_atomic_load (location_t loc, tree function,
6965 				vec<tree, va_gc> *params, tree *new_return)
6966 {
6967   tree p0, p1, p2;
6968   tree I_type, I_type_ptr;
6969   int n = get_atomic_generic_size (loc, function, params);
6970 
6971   /* Size of 0 is an error condition.  */
6972   if (n == 0)
6973     {
6974       *new_return = error_mark_node;
6975       return true;
6976     }
6977 
6978   /* If not a lock-free size, change to the library generic format.  */
6979   if (!atomic_size_supported_p (n))
6980     {
6981       *new_return = add_atomic_size_parameter (n, loc, function, params);
6982       return true;
6983     }
6984 
6985   /* Otherwise, there is a match, so the call needs to be transformed from:
6986        void fn(T* mem, T* return, model)
6987      into
6988        *return = (T) (fn ((In *) mem, model))  */
6989 
6990   p0 = (*params)[0];
6991   p1 = (*params)[1];
6992   p2 = (*params)[2];
6993 
6994   /* Create pointer to appropriate size.  */
6995   I_type = builtin_type_for_size (BITS_PER_UNIT * n, 1);
6996   I_type_ptr = build_pointer_type (I_type);
6997 
6998   /* Convert object pointer to required type.  */
6999   p0 = build1 (VIEW_CONVERT_EXPR, I_type_ptr, p0);
7000   (*params)[0] = p0;
7001 
7002   /* Move memory model to the 2nd position, and end param list.  */
7003   (*params)[1] = p2;
7004   params->truncate (2);
7005 
7006   /* Convert return pointer and dereference it for later assignment.  */
7007   *new_return = build_indirect_ref (loc, p1, RO_UNARY_STAR);
7008 
7009   return false;
7010 }
7011 
7012 
7013 /* This will process an __atomic_store function call, determine whether it
7014    needs to be mapped to the _N variation, or turned into a library call.
7015    LOC is the location of the builtin call.
7016    FUNCTION is the DECL that has been invoked;
7017    PARAMS is the argument list for the call.  The return value is non-null
7018    TRUE is returned if it is translated into the proper format for a call to the
7019    external library, and NEW_RETURN is set the tree for that function.
7020    FALSE is returned if processing for the _N variation is required, and
7021    NEW_RETURN is set to the return value the result is copied into.  */
7022 
7023 static bool
7024 resolve_overloaded_atomic_store (location_t loc, tree function,
7025 				 vec<tree, va_gc> *params, tree *new_return)
7026 {
7027   tree p0, p1;
7028   tree I_type, I_type_ptr;
7029   int n = get_atomic_generic_size (loc, function, params);
7030 
7031   /* Size of 0 is an error condition.  */
7032   if (n == 0)
7033     {
7034       *new_return = error_mark_node;
7035       return true;
7036     }
7037 
7038   /* If not a lock-free size, change to the library generic format.  */
7039   if (!atomic_size_supported_p (n))
7040     {
7041       *new_return = add_atomic_size_parameter (n, loc, function, params);
7042       return true;
7043     }
7044 
7045   /* Otherwise, there is a match, so the call needs to be transformed from:
7046        void fn(T* mem, T* value, model)
7047      into
7048        fn ((In *) mem, (In) *value, model)  */
7049 
7050   p0 = (*params)[0];
7051   p1 = (*params)[1];
7052 
7053   /* Create pointer to appropriate size.  */
7054   I_type = builtin_type_for_size (BITS_PER_UNIT * n, 1);
7055   I_type_ptr = build_pointer_type (I_type);
7056 
7057   /* Convert object pointer to required type.  */
7058   p0 = build1 (VIEW_CONVERT_EXPR, I_type_ptr, p0);
7059   (*params)[0] = p0;
7060 
7061   /* Convert new value to required type, and dereference it.  */
7062   p1 = build_indirect_ref (loc, p1, RO_UNARY_STAR);
7063   p1 = build1 (VIEW_CONVERT_EXPR, I_type, p1);
7064   (*params)[1] = p1;
7065 
7066   /* The memory model is in the right spot already. Return is void.  */
7067   *new_return = NULL_TREE;
7068 
7069   return false;
7070 }
7071 
7072 
7073 /* Some builtin functions are placeholders for other expressions.  This
7074    function should be called immediately after parsing the call expression
7075    before surrounding code has committed to the type of the expression.
7076 
7077    LOC is the location of the builtin call.
7078 
7079    FUNCTION is the DECL that has been invoked; it is known to be a builtin.
7080    PARAMS is the argument list for the call.  The return value is non-null
7081    when expansion is complete, and null if normal processing should
7082    continue.  */
7083 
7084 tree
7085 resolve_overloaded_builtin (location_t loc, tree function,
7086 			    vec<tree, va_gc> *params)
7087 {
7088   enum built_in_function orig_code = DECL_FUNCTION_CODE (function);
7089 
7090   /* Is function one of the _FETCH_OP_ or _OP_FETCH_ built-ins?
7091      Those are not valid to call with a pointer to _Bool (or C++ bool)
7092      and so must be rejected.  */
7093   bool fetch_op = true;
7094   bool orig_format = true;
7095   tree new_return = NULL_TREE;
7096 
7097   switch (DECL_BUILT_IN_CLASS (function))
7098     {
7099     case BUILT_IN_NORMAL:
7100       break;
7101     case BUILT_IN_MD:
7102       if (targetm.resolve_overloaded_builtin)
7103 	return targetm.resolve_overloaded_builtin (loc, function, params);
7104       else
7105 	return NULL_TREE;
7106     default:
7107       return NULL_TREE;
7108     }
7109 
7110   /* Handle BUILT_IN_NORMAL here.  */
7111   switch (orig_code)
7112     {
7113     case BUILT_IN_ATOMIC_EXCHANGE:
7114     case BUILT_IN_ATOMIC_COMPARE_EXCHANGE:
7115     case BUILT_IN_ATOMIC_LOAD:
7116     case BUILT_IN_ATOMIC_STORE:
7117       {
7118 	/* Handle these 4 together so that they can fall through to the next
7119 	   case if the call is transformed to an _N variant.  */
7120         switch (orig_code)
7121 	  {
7122 	  case BUILT_IN_ATOMIC_EXCHANGE:
7123 	    {
7124 	      if (resolve_overloaded_atomic_exchange (loc, function, params,
7125 						      &new_return))
7126 		return new_return;
7127 	      /* Change to the _N variant.  */
7128 	      orig_code = BUILT_IN_ATOMIC_EXCHANGE_N;
7129 	      break;
7130 	    }
7131 
7132 	  case BUILT_IN_ATOMIC_COMPARE_EXCHANGE:
7133 	    {
7134 	      if (resolve_overloaded_atomic_compare_exchange (loc, function,
7135 							      params,
7136 							      &new_return))
7137 		return new_return;
7138 	      /* Change to the _N variant.  */
7139 	      orig_code = BUILT_IN_ATOMIC_COMPARE_EXCHANGE_N;
7140 	      break;
7141 	    }
7142 	  case BUILT_IN_ATOMIC_LOAD:
7143 	    {
7144 	      if (resolve_overloaded_atomic_load (loc, function, params,
7145 						  &new_return))
7146 		return new_return;
7147 	      /* Change to the _N variant.  */
7148 	      orig_code = BUILT_IN_ATOMIC_LOAD_N;
7149 	      break;
7150 	    }
7151 	  case BUILT_IN_ATOMIC_STORE:
7152 	    {
7153 	      if (resolve_overloaded_atomic_store (loc, function, params,
7154 						   &new_return))
7155 		return new_return;
7156 	      /* Change to the _N variant.  */
7157 	      orig_code = BUILT_IN_ATOMIC_STORE_N;
7158 	      break;
7159 	    }
7160 	  default:
7161 	    gcc_unreachable ();
7162 	  }
7163       }
7164       /* FALLTHRU */
7165     case BUILT_IN_ATOMIC_EXCHANGE_N:
7166     case BUILT_IN_ATOMIC_COMPARE_EXCHANGE_N:
7167     case BUILT_IN_ATOMIC_LOAD_N:
7168     case BUILT_IN_ATOMIC_STORE_N:
7169       fetch_op = false;
7170       /* FALLTHRU */
7171     case BUILT_IN_ATOMIC_ADD_FETCH_N:
7172     case BUILT_IN_ATOMIC_SUB_FETCH_N:
7173     case BUILT_IN_ATOMIC_AND_FETCH_N:
7174     case BUILT_IN_ATOMIC_NAND_FETCH_N:
7175     case BUILT_IN_ATOMIC_XOR_FETCH_N:
7176     case BUILT_IN_ATOMIC_OR_FETCH_N:
7177     case BUILT_IN_ATOMIC_FETCH_ADD_N:
7178     case BUILT_IN_ATOMIC_FETCH_SUB_N:
7179     case BUILT_IN_ATOMIC_FETCH_AND_N:
7180     case BUILT_IN_ATOMIC_FETCH_NAND_N:
7181     case BUILT_IN_ATOMIC_FETCH_XOR_N:
7182     case BUILT_IN_ATOMIC_FETCH_OR_N:
7183       orig_format = false;
7184       /* FALLTHRU */
7185     case BUILT_IN_SYNC_FETCH_AND_ADD_N:
7186     case BUILT_IN_SYNC_FETCH_AND_SUB_N:
7187     case BUILT_IN_SYNC_FETCH_AND_OR_N:
7188     case BUILT_IN_SYNC_FETCH_AND_AND_N:
7189     case BUILT_IN_SYNC_FETCH_AND_XOR_N:
7190     case BUILT_IN_SYNC_FETCH_AND_NAND_N:
7191     case BUILT_IN_SYNC_ADD_AND_FETCH_N:
7192     case BUILT_IN_SYNC_SUB_AND_FETCH_N:
7193     case BUILT_IN_SYNC_OR_AND_FETCH_N:
7194     case BUILT_IN_SYNC_AND_AND_FETCH_N:
7195     case BUILT_IN_SYNC_XOR_AND_FETCH_N:
7196     case BUILT_IN_SYNC_NAND_AND_FETCH_N:
7197     case BUILT_IN_SYNC_BOOL_COMPARE_AND_SWAP_N:
7198     case BUILT_IN_SYNC_VAL_COMPARE_AND_SWAP_N:
7199     case BUILT_IN_SYNC_LOCK_TEST_AND_SET_N:
7200     case BUILT_IN_SYNC_LOCK_RELEASE_N:
7201       {
7202 	/* The following are not _FETCH_OPs and must be accepted with
7203 	   pointers to _Bool (or C++ bool).  */
7204 	if (fetch_op)
7205 	  fetch_op =
7206 	    (orig_code != BUILT_IN_SYNC_BOOL_COMPARE_AND_SWAP_N
7207 	     && orig_code != BUILT_IN_SYNC_VAL_COMPARE_AND_SWAP_N
7208 	     && orig_code != BUILT_IN_SYNC_LOCK_TEST_AND_SET_N
7209 	     && orig_code != BUILT_IN_SYNC_LOCK_RELEASE_N);
7210 
7211 	int n = sync_resolve_size (function, params, fetch_op);
7212 	tree new_function, first_param, result;
7213 	enum built_in_function fncode;
7214 
7215 	if (n == 0)
7216 	  return error_mark_node;
7217 
7218 	fncode = (enum built_in_function)((int)orig_code + exact_log2 (n) + 1);
7219 	new_function = builtin_decl_explicit (fncode);
7220 	if (!sync_resolve_params (loc, function, new_function, params,
7221 				  orig_format))
7222 	  return error_mark_node;
7223 
7224 	first_param = (*params)[0];
7225 	result = build_function_call_vec (loc, vNULL, new_function, params,
7226 					  NULL);
7227 	if (result == error_mark_node)
7228 	  return result;
7229 	if (orig_code != BUILT_IN_SYNC_BOOL_COMPARE_AND_SWAP_N
7230 	    && orig_code != BUILT_IN_SYNC_LOCK_RELEASE_N
7231 	    && orig_code != BUILT_IN_ATOMIC_STORE_N
7232 	    && orig_code != BUILT_IN_ATOMIC_COMPARE_EXCHANGE_N)
7233 	  result = sync_resolve_return (first_param, result, orig_format);
7234 
7235 	if (fetch_op)
7236 	  /* Prevent -Wunused-value warning.  */
7237 	  TREE_USED (result) = true;
7238 
7239 	/* If new_return is set, assign function to that expr and cast the
7240 	   result to void since the generic interface returned void.  */
7241 	if (new_return)
7242 	  {
7243 	    /* Cast function result from I{1,2,4,8,16} to the required type.  */
7244 	    result = build1 (VIEW_CONVERT_EXPR, TREE_TYPE (new_return), result);
7245 	    result = build2 (MODIFY_EXPR, TREE_TYPE (new_return), new_return,
7246 			     result);
7247 	    TREE_SIDE_EFFECTS (result) = 1;
7248 	    protected_set_expr_location (result, loc);
7249 	    result = convert (void_type_node, result);
7250 	  }
7251 	return result;
7252       }
7253 
7254     default:
7255       return NULL_TREE;
7256     }
7257 }
7258 
7259 /* vector_types_compatible_elements_p is used in type checks of vectors
7260    values used as operands of binary operators.  Where it returns true, and
7261    the other checks of the caller succeed (being vector types in he first
7262    place, and matching number of elements), we can just treat the types
7263    as essentially the same.
7264    Contrast with vector_targets_convertible_p, which is used for vector
7265    pointer types,  and vector_types_convertible_p, which will allow
7266    language-specific matches under the control of flag_lax_vector_conversions,
7267    and might still require a conversion.  */
7268 /* True if vector types T1 and T2 can be inputs to the same binary
7269    operator without conversion.
7270    We don't check the overall vector size here because some of our callers
7271    want to give different error messages when the vectors are compatible
7272    except for the element count.  */
7273 
7274 bool
7275 vector_types_compatible_elements_p (tree t1, tree t2)
7276 {
7277   bool opaque = TYPE_VECTOR_OPAQUE (t1) || TYPE_VECTOR_OPAQUE (t2);
7278   t1 = TREE_TYPE (t1);
7279   t2 = TREE_TYPE (t2);
7280 
7281   enum tree_code c1 = TREE_CODE (t1), c2 = TREE_CODE (t2);
7282 
7283   gcc_assert ((c1 == INTEGER_TYPE || c1 == REAL_TYPE || c1 == FIXED_POINT_TYPE)
7284 	      && (c2 == INTEGER_TYPE || c2 == REAL_TYPE
7285 		  || c2 == FIXED_POINT_TYPE));
7286 
7287   t1 = c_common_signed_type (t1);
7288   t2 = c_common_signed_type (t2);
7289   /* Equality works here because c_common_signed_type uses
7290      TYPE_MAIN_VARIANT.  */
7291   if (t1 == t2)
7292     return true;
7293   if (opaque && c1 == c2
7294       && (c1 == INTEGER_TYPE || c1 == REAL_TYPE)
7295       && TYPE_PRECISION (t1) == TYPE_PRECISION (t2))
7296     return true;
7297   return false;
7298 }
7299 
7300 /* Check for missing format attributes on function pointers.  LTYPE is
7301    the new type or left-hand side type.  RTYPE is the old type or
7302    right-hand side type.  Returns TRUE if LTYPE is missing the desired
7303    attribute.  */
7304 
7305 bool
7306 check_missing_format_attribute (tree ltype, tree rtype)
7307 {
7308   tree const ttr = TREE_TYPE (rtype), ttl = TREE_TYPE (ltype);
7309   tree ra;
7310 
7311   for (ra = TYPE_ATTRIBUTES (ttr); ra; ra = TREE_CHAIN (ra))
7312     if (is_attribute_p ("format", TREE_PURPOSE (ra)))
7313       break;
7314   if (ra)
7315     {
7316       tree la;
7317       for (la = TYPE_ATTRIBUTES (ttl); la; la = TREE_CHAIN (la))
7318 	if (is_attribute_p ("format", TREE_PURPOSE (la)))
7319 	  break;
7320       return !la;
7321     }
7322   else
7323     return false;
7324 }
7325 
7326 /* Setup a TYPE_DECL node as a typedef representation.
7327 
7328    X is a TYPE_DECL for a typedef statement.  Create a brand new
7329    ..._TYPE node (which will be just a variant of the existing
7330    ..._TYPE node with identical properties) and then install X
7331    as the TYPE_NAME of this brand new (duplicate) ..._TYPE node.
7332 
7333    The whole point here is to end up with a situation where each
7334    and every ..._TYPE node the compiler creates will be uniquely
7335    associated with AT MOST one node representing a typedef name.
7336    This way, even though the compiler substitutes corresponding
7337    ..._TYPE nodes for TYPE_DECL (i.e. "typedef name") nodes very
7338    early on, later parts of the compiler can always do the reverse
7339    translation and get back the corresponding typedef name.  For
7340    example, given:
7341 
7342 	typedef struct S MY_TYPE;
7343 	MY_TYPE object;
7344 
7345    Later parts of the compiler might only know that `object' was of
7346    type `struct S' if it were not for code just below.  With this
7347    code however, later parts of the compiler see something like:
7348 
7349 	struct S' == struct S
7350 	typedef struct S' MY_TYPE;
7351 	struct S' object;
7352 
7353     And they can then deduce (from the node for type struct S') that
7354     the original object declaration was:
7355 
7356 		MY_TYPE object;
7357 
7358     Being able to do this is important for proper support of protoize,
7359     and also for generating precise symbolic debugging information
7360     which takes full account of the programmer's (typedef) vocabulary.
7361 
7362     Obviously, we don't want to generate a duplicate ..._TYPE node if
7363     the TYPE_DECL node that we are now processing really represents a
7364     standard built-in type.  */
7365 
7366 void
7367 set_underlying_type (tree x)
7368 {
7369   if (x == error_mark_node)
7370     return;
7371   if (DECL_IS_BUILTIN (x) && TREE_CODE (TREE_TYPE (x)) != ARRAY_TYPE)
7372     {
7373       if (TYPE_NAME (TREE_TYPE (x)) == 0)
7374 	TYPE_NAME (TREE_TYPE (x)) = x;
7375     }
7376   else if (TREE_TYPE (x) != error_mark_node
7377 	   && DECL_ORIGINAL_TYPE (x) == NULL_TREE)
7378     {
7379       tree tt = TREE_TYPE (x);
7380       DECL_ORIGINAL_TYPE (x) = tt;
7381       tt = build_variant_type_copy (tt);
7382       TYPE_STUB_DECL (tt) = TYPE_STUB_DECL (DECL_ORIGINAL_TYPE (x));
7383       TYPE_NAME (tt) = x;
7384 
7385       /* Mark the type as used only when its type decl is decorated
7386 	 with attribute unused.  */
7387       if (lookup_attribute ("unused", DECL_ATTRIBUTES (x)))
7388 	TREE_USED (tt) = 1;
7389 
7390       TREE_TYPE (x) = tt;
7391     }
7392 }
7393 
7394 /* Record the types used by the current global variable declaration
7395    being parsed, so that we can decide later to emit their debug info.
7396    Those types are in types_used_by_cur_var_decl, and we are going to
7397    store them in the types_used_by_vars_hash hash table.
7398    DECL is the declaration of the global variable that has been parsed.  */
7399 
7400 void
7401 record_types_used_by_current_var_decl (tree decl)
7402 {
7403   gcc_assert (decl && DECL_P (decl) && TREE_STATIC (decl));
7404 
7405   while (types_used_by_cur_var_decl && !types_used_by_cur_var_decl->is_empty ())
7406     {
7407       tree type = types_used_by_cur_var_decl->pop ();
7408       types_used_by_var_decl_insert (type, decl);
7409     }
7410 }
7411 
7412 /* The C and C++ parsers both use vectors to hold function arguments.
7413    For efficiency, we keep a cache of unused vectors.  This is the
7414    cache.  */
7415 
7416 typedef vec<tree, va_gc> *tree_gc_vec;
7417 static GTY((deletable)) vec<tree_gc_vec, va_gc> *tree_vector_cache;
7418 
7419 /* Return a new vector from the cache.  If the cache is empty,
7420    allocate a new vector.  These vectors are GC'ed, so it is OK if the
7421    pointer is not released..  */
7422 
7423 vec<tree, va_gc> *
7424 make_tree_vector (void)
7425 {
7426   if (tree_vector_cache && !tree_vector_cache->is_empty ())
7427     return tree_vector_cache->pop ();
7428   else
7429     {
7430       /* Passing 0 to vec::alloc returns NULL, and our callers require
7431 	 that we always return a non-NULL value.  The vector code uses
7432 	 4 when growing a NULL vector, so we do too.  */
7433       vec<tree, va_gc> *v;
7434       vec_alloc (v, 4);
7435       return v;
7436     }
7437 }
7438 
7439 /* Release a vector of trees back to the cache.  */
7440 
7441 void
7442 release_tree_vector (vec<tree, va_gc> *vec)
7443 {
7444   if (vec != NULL)
7445     {
7446       vec->truncate (0);
7447       vec_safe_push (tree_vector_cache, vec);
7448     }
7449 }
7450 
7451 /* Get a new tree vector holding a single tree.  */
7452 
7453 vec<tree, va_gc> *
7454 make_tree_vector_single (tree t)
7455 {
7456   vec<tree, va_gc> *ret = make_tree_vector ();
7457   ret->quick_push (t);
7458   return ret;
7459 }
7460 
7461 /* Get a new tree vector of the TREE_VALUEs of a TREE_LIST chain.  */
7462 
7463 vec<tree, va_gc> *
7464 make_tree_vector_from_list (tree list)
7465 {
7466   vec<tree, va_gc> *ret = make_tree_vector ();
7467   for (; list; list = TREE_CHAIN (list))
7468     vec_safe_push (ret, TREE_VALUE (list));
7469   return ret;
7470 }
7471 
7472 /* Get a new tree vector of the values of a CONSTRUCTOR.  */
7473 
7474 vec<tree, va_gc> *
7475 make_tree_vector_from_ctor (tree ctor)
7476 {
7477   vec<tree,va_gc> *ret = make_tree_vector ();
7478   vec_safe_reserve (ret, CONSTRUCTOR_NELTS (ctor));
7479   for (unsigned i = 0; i < CONSTRUCTOR_NELTS (ctor); ++i)
7480     ret->quick_push (CONSTRUCTOR_ELT (ctor, i)->value);
7481   return ret;
7482 }
7483 
7484 /* Get a new tree vector which is a copy of an existing one.  */
7485 
7486 vec<tree, va_gc> *
7487 make_tree_vector_copy (const vec<tree, va_gc> *orig)
7488 {
7489   vec<tree, va_gc> *ret;
7490   unsigned int ix;
7491   tree t;
7492 
7493   ret = make_tree_vector ();
7494   vec_safe_reserve (ret, vec_safe_length (orig));
7495   FOR_EACH_VEC_SAFE_ELT (orig, ix, t)
7496     ret->quick_push (t);
7497   return ret;
7498 }
7499 
7500 /* Return true if KEYWORD starts a type specifier.  */
7501 
7502 bool
7503 keyword_begins_type_specifier (enum rid keyword)
7504 {
7505   switch (keyword)
7506     {
7507     case RID_AUTO_TYPE:
7508     case RID_INT:
7509     case RID_CHAR:
7510     case RID_FLOAT:
7511     case RID_DOUBLE:
7512     case RID_VOID:
7513     case RID_UNSIGNED:
7514     case RID_LONG:
7515     case RID_SHORT:
7516     case RID_SIGNED:
7517     CASE_RID_FLOATN_NX:
7518     case RID_DFLOAT32:
7519     case RID_DFLOAT64:
7520     case RID_DFLOAT128:
7521     case RID_FRACT:
7522     case RID_ACCUM:
7523     case RID_BOOL:
7524     case RID_WCHAR:
7525     case RID_CHAR16:
7526     case RID_CHAR32:
7527     case RID_SAT:
7528     case RID_COMPLEX:
7529     case RID_TYPEOF:
7530     case RID_STRUCT:
7531     case RID_CLASS:
7532     case RID_UNION:
7533     case RID_ENUM:
7534       return true;
7535     default:
7536       if (keyword >= RID_FIRST_INT_N
7537 	  && keyword < RID_FIRST_INT_N + NUM_INT_N_ENTS
7538 	  && int_n_enabled_p[keyword-RID_FIRST_INT_N])
7539 	return true;
7540       return false;
7541     }
7542 }
7543 
7544 /* Return true if KEYWORD names a type qualifier.  */
7545 
7546 bool
7547 keyword_is_type_qualifier (enum rid keyword)
7548 {
7549   switch (keyword)
7550     {
7551     case RID_CONST:
7552     case RID_VOLATILE:
7553     case RID_RESTRICT:
7554     case RID_ATOMIC:
7555       return true;
7556     default:
7557       return false;
7558     }
7559 }
7560 
7561 /* Return true if KEYWORD names a storage class specifier.
7562 
7563    RID_TYPEDEF is not included in this list despite `typedef' being
7564    listed in C99 6.7.1.1.  6.7.1.3 indicates that `typedef' is listed as
7565    such for syntactic convenience only.  */
7566 
7567 bool
7568 keyword_is_storage_class_specifier (enum rid keyword)
7569 {
7570   switch (keyword)
7571     {
7572     case RID_STATIC:
7573     case RID_EXTERN:
7574     case RID_REGISTER:
7575     case RID_AUTO:
7576     case RID_MUTABLE:
7577     case RID_THREAD:
7578       return true;
7579     default:
7580       return false;
7581     }
7582 }
7583 
7584 /* Return true if KEYWORD names a function-specifier [dcl.fct.spec].  */
7585 
7586 static bool
7587 keyword_is_function_specifier (enum rid keyword)
7588 {
7589   switch (keyword)
7590     {
7591     case RID_INLINE:
7592     case RID_NORETURN:
7593     case RID_VIRTUAL:
7594     case RID_EXPLICIT:
7595       return true;
7596     default:
7597       return false;
7598     }
7599 }
7600 
7601 /* Return true if KEYWORD names a decl-specifier [dcl.spec] or a
7602    declaration-specifier (C99 6.7).  */
7603 
7604 bool
7605 keyword_is_decl_specifier (enum rid keyword)
7606 {
7607   if (keyword_is_storage_class_specifier (keyword)
7608       || keyword_is_type_qualifier (keyword)
7609       || keyword_is_function_specifier (keyword))
7610     return true;
7611 
7612   switch (keyword)
7613     {
7614     case RID_TYPEDEF:
7615     case RID_FRIEND:
7616     case RID_CONSTEXPR:
7617       return true;
7618     default:
7619       return false;
7620     }
7621 }
7622 
7623 /* Initialize language-specific-bits of tree_contains_struct.  */
7624 
7625 void
7626 c_common_init_ts (void)
7627 {
7628   MARK_TS_TYPED (C_MAYBE_CONST_EXPR);
7629   MARK_TS_TYPED (EXCESS_PRECISION_EXPR);
7630 }
7631 
7632 /* Build a user-defined numeric literal out of an integer constant type VALUE
7633    with identifier SUFFIX.  */
7634 
7635 tree
7636 build_userdef_literal (tree suffix_id, tree value,
7637 		       enum overflow_type overflow, tree num_string)
7638 {
7639   tree literal = make_node (USERDEF_LITERAL);
7640   USERDEF_LITERAL_SUFFIX_ID (literal) = suffix_id;
7641   USERDEF_LITERAL_VALUE (literal) = value;
7642   USERDEF_LITERAL_OVERFLOW (literal) = overflow;
7643   USERDEF_LITERAL_NUM_STRING (literal) = num_string;
7644   return literal;
7645 }
7646 
7647 /* For vector[index], convert the vector to an array of the underlying type.
7648    Return true if the resulting ARRAY_REF should not be an lvalue.  */
7649 
7650 bool
7651 convert_vector_to_array_for_subscript (location_t loc,
7652 				       tree *vecp, tree index)
7653 {
7654   bool ret = false;
7655   if (VECTOR_TYPE_P (TREE_TYPE (*vecp)))
7656     {
7657       tree type = TREE_TYPE (*vecp);
7658 
7659       ret = !lvalue_p (*vecp);
7660 
7661       if (TREE_CODE (index) == INTEGER_CST)
7662         if (!tree_fits_uhwi_p (index)
7663 	    || maybe_ge (tree_to_uhwi (index), TYPE_VECTOR_SUBPARTS (type)))
7664           warning_at (loc, OPT_Warray_bounds, "index value is out of bound");
7665 
7666       /* We are building an ARRAY_REF so mark the vector as addressable
7667          to not run into the gimplifiers premature setting of DECL_GIMPLE_REG_P
7668 	 for function parameters.  */
7669       c_common_mark_addressable_vec (*vecp);
7670 
7671       *vecp = build1 (VIEW_CONVERT_EXPR,
7672 		      build_array_type_nelts (TREE_TYPE (type),
7673 					      TYPE_VECTOR_SUBPARTS (type)),
7674 		      *vecp);
7675     }
7676   return ret;
7677 }
7678 
7679 /* Determine which of the operands, if any, is a scalar that needs to be
7680    converted to a vector, for the range of operations.  */
7681 enum stv_conv
7682 scalar_to_vector (location_t loc, enum tree_code code, tree op0, tree op1,
7683 		  bool complain)
7684 {
7685   tree type0 = TREE_TYPE (op0);
7686   tree type1 = TREE_TYPE (op1);
7687   bool integer_only_op = false;
7688   enum stv_conv ret = stv_firstarg;
7689 
7690   gcc_assert (VECTOR_TYPE_P (type0) || VECTOR_TYPE_P (type1));
7691   switch (code)
7692     {
7693       /* Most GENERIC binary expressions require homogeneous arguments.
7694 	 LSHIFT_EXPR and RSHIFT_EXPR are exceptions and accept a first
7695 	 argument that is a vector and a second one that is a scalar, so
7696 	 we never return stv_secondarg for them.  */
7697       case RSHIFT_EXPR:
7698       case LSHIFT_EXPR:
7699 	if (TREE_CODE (type0) == INTEGER_TYPE
7700 	    && TREE_CODE (TREE_TYPE (type1)) == INTEGER_TYPE)
7701 	  {
7702 	    if (unsafe_conversion_p (loc, TREE_TYPE (type1), op0,
7703 				     NULL_TREE, false))
7704 	      {
7705 		if (complain)
7706 		  error_at (loc, "conversion of scalar %qT to vector %qT "
7707 			    "involves truncation", type0, type1);
7708 		return stv_error;
7709 	      }
7710 	    else
7711 	      return stv_firstarg;
7712 	  }
7713 	break;
7714 
7715       case BIT_IOR_EXPR:
7716       case BIT_XOR_EXPR:
7717       case BIT_AND_EXPR:
7718 	integer_only_op = true;
7719 	/* fall through */
7720 
7721       case VEC_COND_EXPR:
7722 
7723       case PLUS_EXPR:
7724       case MINUS_EXPR:
7725       case MULT_EXPR:
7726       case TRUNC_DIV_EXPR:
7727       case CEIL_DIV_EXPR:
7728       case FLOOR_DIV_EXPR:
7729       case ROUND_DIV_EXPR:
7730       case EXACT_DIV_EXPR:
7731       case TRUNC_MOD_EXPR:
7732       case FLOOR_MOD_EXPR:
7733       case RDIV_EXPR:
7734       case EQ_EXPR:
7735       case NE_EXPR:
7736       case LE_EXPR:
7737       case GE_EXPR:
7738       case LT_EXPR:
7739       case GT_EXPR:
7740       /* What about UNLT_EXPR?  */
7741 	if (VECTOR_TYPE_P (type0))
7742 	  {
7743 	    ret = stv_secondarg;
7744 	    std::swap (type0, type1);
7745 	    std::swap (op0, op1);
7746 	  }
7747 
7748 	if (TREE_CODE (type0) == INTEGER_TYPE
7749 	    && TREE_CODE (TREE_TYPE (type1)) == INTEGER_TYPE)
7750 	  {
7751 	    if (unsafe_conversion_p (loc, TREE_TYPE (type1), op0,
7752 				     NULL_TREE, false))
7753 	      {
7754 		if (complain)
7755 		  error_at (loc, "conversion of scalar %qT to vector %qT "
7756 			    "involves truncation", type0, type1);
7757 		return stv_error;
7758 	      }
7759 	    return ret;
7760 	  }
7761 	else if (!integer_only_op
7762 		    /* Allow integer --> real conversion if safe.  */
7763 		 && (TREE_CODE (type0) == REAL_TYPE
7764 		     || TREE_CODE (type0) == INTEGER_TYPE)
7765 		 && SCALAR_FLOAT_TYPE_P (TREE_TYPE (type1)))
7766 	  {
7767 	    if (unsafe_conversion_p (loc, TREE_TYPE (type1), op0,
7768 				     NULL_TREE, false))
7769 	      {
7770 		if (complain)
7771 		  error_at (loc, "conversion of scalar %qT to vector %qT "
7772 			    "involves truncation", type0, type1);
7773 		return stv_error;
7774 	      }
7775 	    return ret;
7776 	  }
7777       default:
7778 	break;
7779     }
7780 
7781   return stv_nothing;
7782 }
7783 
7784 /* Return the alignment of std::max_align_t.
7785 
7786    [support.types.layout] The type max_align_t is a POD type whose alignment
7787    requirement is at least as great as that of every scalar type, and whose
7788    alignment requirement is supported in every context.  */
7789 
7790 unsigned
7791 max_align_t_align ()
7792 {
7793   unsigned int max_align = MAX (TYPE_ALIGN (long_long_integer_type_node),
7794 				TYPE_ALIGN (long_double_type_node));
7795   if (float128_type_node != NULL_TREE)
7796     max_align = MAX (max_align, TYPE_ALIGN (float128_type_node));
7797   return max_align;
7798 }
7799 
7800 /* Return true iff ALIGN is an integral constant that is a fundamental
7801    alignment, as defined by [basic.align] in the c++-11
7802    specifications.
7803 
7804    That is:
7805 
7806        [A fundamental alignment is represented by an alignment less than or
7807         equal to the greatest alignment supported by the implementation
7808         in all contexts, which is equal to alignof(max_align_t)].  */
7809 
7810 bool
7811 cxx_fundamental_alignment_p (unsigned align)
7812 {
7813   return (align <= max_align_t_align ());
7814 }
7815 
7816 /* Return true if T is a pointer to a zero-sized aggregate.  */
7817 
7818 bool
7819 pointer_to_zero_sized_aggr_p (tree t)
7820 {
7821   if (!POINTER_TYPE_P (t))
7822     return false;
7823   t = TREE_TYPE (t);
7824   return (TYPE_SIZE (t) && integer_zerop (TYPE_SIZE (t)));
7825 }
7826 
7827 /* For an EXPR of a FUNCTION_TYPE that references a GCC built-in function
7828    with no library fallback or for an ADDR_EXPR whose operand is such type
7829    issues an error pointing to the location LOC.
7830    Returns true when the expression has been diagnosed and false
7831    otherwise.  */
7832 
7833 bool
7834 reject_gcc_builtin (const_tree expr, location_t loc /* = UNKNOWN_LOCATION */)
7835 {
7836   if (TREE_CODE (expr) == ADDR_EXPR)
7837     expr = TREE_OPERAND (expr, 0);
7838 
7839   STRIP_ANY_LOCATION_WRAPPER (expr);
7840 
7841   if (TREE_TYPE (expr)
7842       && TREE_CODE (TREE_TYPE (expr)) == FUNCTION_TYPE
7843       && TREE_CODE (expr) == FUNCTION_DECL
7844       /* The intersection of DECL_BUILT_IN and DECL_IS_BUILTIN avoids
7845 	 false positives for user-declared built-ins such as abs or
7846 	 strlen, and for C++ operators new and delete.
7847 	 The c_decl_implicit() test avoids false positives for implicitly
7848 	 declared built-ins with library fallbacks (such as abs).  */
7849       && DECL_BUILT_IN (expr)
7850       && DECL_IS_BUILTIN (expr)
7851       && !c_decl_implicit (expr)
7852       && !DECL_ASSEMBLER_NAME_SET_P (expr))
7853     {
7854       if (loc == UNKNOWN_LOCATION)
7855 	loc = EXPR_LOC_OR_LOC (expr, input_location);
7856 
7857       /* Reject arguments that are built-in functions with
7858 	 no library fallback.  */
7859       error_at (loc, "built-in function %qE must be directly called", expr);
7860 
7861       return true;
7862     }
7863 
7864   return false;
7865 }
7866 
7867 /* Check if array size calculations overflow or if the array covers more
7868    than half of the address space.  Return true if the size of the array
7869    is valid, false otherwise.  TYPE is the type of the array and NAME is
7870    the name of the array, or NULL_TREE for unnamed arrays.  */
7871 
7872 bool
7873 valid_array_size_p (location_t loc, tree type, tree name)
7874 {
7875   if (type != error_mark_node
7876       && COMPLETE_TYPE_P (type)
7877       && TREE_CODE (TYPE_SIZE_UNIT (type)) == INTEGER_CST
7878       && !valid_constant_size_p (TYPE_SIZE_UNIT (type)))
7879     {
7880       if (name)
7881 	error_at (loc, "size of array %qE is too large", name);
7882       else
7883 	error_at (loc, "size of unnamed array is too large");
7884       return false;
7885     }
7886   return true;
7887 }
7888 
7889 /* Read SOURCE_DATE_EPOCH from environment to have a deterministic
7890    timestamp to replace embedded current dates to get reproducible
7891    results.  Returns -1 if SOURCE_DATE_EPOCH is not defined.  */
7892 
7893 time_t
7894 cb_get_source_date_epoch (cpp_reader *pfile ATTRIBUTE_UNUSED)
7895 {
7896   char *source_date_epoch;
7897   int64_t epoch;
7898   char *endptr;
7899 
7900   source_date_epoch = getenv ("SOURCE_DATE_EPOCH");
7901   if (!source_date_epoch)
7902     return (time_t) -1;
7903 
7904   errno = 0;
7905 #if defined(INT64_T_IS_LONG)
7906   epoch = strtol (source_date_epoch, &endptr, 10);
7907 #else
7908   epoch = strtoll (source_date_epoch, &endptr, 10);
7909 #endif
7910   if (errno != 0 || endptr == source_date_epoch || *endptr != '\0'
7911       || epoch < 0 || epoch > MAX_SOURCE_DATE_EPOCH)
7912     {
7913       error_at (input_location, "environment variable SOURCE_DATE_EPOCH must "
7914 	        "expand to a non-negative integer less than or equal to %wd",
7915 		MAX_SOURCE_DATE_EPOCH);
7916       return (time_t) -1;
7917     }
7918 
7919   return (time_t) epoch;
7920 }
7921 
7922 /* Callback for libcpp for offering spelling suggestions for misspelled
7923    directives.  GOAL is an unrecognized string; CANDIDATES is a
7924    NULL-terminated array of candidate strings.  Return the closest
7925    match to GOAL within CANDIDATES, or NULL if none are good
7926    suggestions.  */
7927 
7928 const char *
7929 cb_get_suggestion (cpp_reader *, const char *goal,
7930 		   const char *const *candidates)
7931 {
7932   best_match<const char *, const char *> bm (goal);
7933   while (*candidates)
7934     bm.consider (*candidates++);
7935   return bm.get_best_meaningful_candidate ();
7936 }
7937 
7938 /* Return the latice point which is the wider of the two FLT_EVAL_METHOD
7939    modes X, Y.  This isn't just  >, as the FLT_EVAL_METHOD values added
7940    by C TS 18661-3 for interchange  types that are computed in their
7941    native precision are larger than the C11 values for evaluating in the
7942    precision of float/double/long double.  If either mode is
7943    FLT_EVAL_METHOD_UNPREDICTABLE, return that.  */
7944 
7945 enum flt_eval_method
7946 excess_precision_mode_join (enum flt_eval_method x,
7947 			    enum flt_eval_method y)
7948 {
7949   if (x == FLT_EVAL_METHOD_UNPREDICTABLE
7950       || y == FLT_EVAL_METHOD_UNPREDICTABLE)
7951     return FLT_EVAL_METHOD_UNPREDICTABLE;
7952 
7953   /* GCC only supports one interchange type right now, _Float16.  If
7954      we're evaluating _Float16 in 16-bit precision, then flt_eval_method
7955      will be FLT_EVAL_METHOD_PROMOTE_TO_FLOAT16.  */
7956   if (x == FLT_EVAL_METHOD_PROMOTE_TO_FLOAT16)
7957     return y;
7958   if (y == FLT_EVAL_METHOD_PROMOTE_TO_FLOAT16)
7959     return x;
7960 
7961   /* Other values for flt_eval_method are directly comparable, and we want
7962      the maximum.  */
7963   return MAX (x, y);
7964 }
7965 
7966 /* Return the value that should be set for FLT_EVAL_METHOD in the
7967    context of ISO/IEC TS 18861-3.
7968 
7969    This relates to the effective excess precision seen by the user,
7970    which is the join point of the precision the target requests for
7971    -fexcess-precision={standard,fast} and the implicit excess precision
7972    the target uses.  */
7973 
7974 static enum flt_eval_method
7975 c_ts18661_flt_eval_method (void)
7976 {
7977   enum flt_eval_method implicit
7978     = targetm.c.excess_precision (EXCESS_PRECISION_TYPE_IMPLICIT);
7979 
7980   enum excess_precision_type flag_type
7981     = (flag_excess_precision_cmdline == EXCESS_PRECISION_STANDARD
7982        ? EXCESS_PRECISION_TYPE_STANDARD
7983        : EXCESS_PRECISION_TYPE_FAST);
7984 
7985   enum flt_eval_method requested
7986     = targetm.c.excess_precision (flag_type);
7987 
7988   return excess_precision_mode_join (implicit, requested);
7989 }
7990 
7991 /* As c_cpp_ts18661_flt_eval_method, but clamps the expected values to
7992    those that were permitted by C11.  That is to say, eliminates
7993    FLT_EVAL_METHOD_PROMOTE_TO_FLOAT16.  */
7994 
7995 static enum flt_eval_method
7996 c_c11_flt_eval_method (void)
7997 {
7998   return excess_precision_mode_join (c_ts18661_flt_eval_method (),
7999 				     FLT_EVAL_METHOD_PROMOTE_TO_FLOAT);
8000 }
8001 
8002 /* Return the value that should be set for FLT_EVAL_METHOD.
8003    MAYBE_C11_ONLY_P is TRUE if we should check
8004    FLAG_PERMITTED_EVAL_METHODS as to whether we should limit the possible
8005    values we can return to those from C99/C11, and FALSE otherwise.
8006    See the comments on c_ts18661_flt_eval_method for what value we choose
8007    to set here.  */
8008 
8009 int
8010 c_flt_eval_method (bool maybe_c11_only_p)
8011 {
8012   if (maybe_c11_only_p
8013       && flag_permitted_flt_eval_methods
8014 	  == PERMITTED_FLT_EVAL_METHODS_C11)
8015     return c_c11_flt_eval_method ();
8016   else
8017     return c_ts18661_flt_eval_method ();
8018 }
8019 
8020 /* An enum for get_missing_token_insertion_kind for describing the best
8021    place to insert a missing token, if there is one.  */
8022 
8023 enum missing_token_insertion_kind
8024 {
8025   MTIK_IMPOSSIBLE,
8026   MTIK_INSERT_BEFORE_NEXT,
8027   MTIK_INSERT_AFTER_PREV
8028 };
8029 
8030 /* Given a missing token of TYPE, determine if it is reasonable to
8031    emit a fix-it hint suggesting the insertion of the token, and,
8032    if so, where the token should be inserted relative to other tokens.
8033 
8034    It only makes sense to do this for values of TYPE that are symbols.
8035 
8036    Some symbols should go before the next token, e.g. in:
8037      if flag)
8038    we want to insert the missing '(' immediately before "flag",
8039    giving:
8040      if (flag)
8041    rather than:
8042      if( flag)
8043    These use MTIK_INSERT_BEFORE_NEXT.
8044 
8045    Other symbols should go after the previous token, e.g. in:
8046      if (flag
8047        do_something ();
8048    we want to insert the missing ')' immediately after the "flag",
8049    giving:
8050      if (flag)
8051        do_something ();
8052    rather than:
8053      if (flag
8054        )do_something ();
8055    These use MTIK_INSERT_AFTER_PREV.  */
8056 
8057 static enum missing_token_insertion_kind
8058 get_missing_token_insertion_kind (enum cpp_ttype type)
8059 {
8060   switch (type)
8061     {
8062       /* Insert missing "opening" brackets immediately
8063 	 before the next token.  */
8064     case CPP_OPEN_SQUARE:
8065     case CPP_OPEN_PAREN:
8066       return MTIK_INSERT_BEFORE_NEXT;
8067 
8068       /* Insert other missing symbols immediately after
8069 	 the previous token.  */
8070     case CPP_CLOSE_PAREN:
8071     case CPP_CLOSE_SQUARE:
8072     case CPP_SEMICOLON:
8073     case CPP_COMMA:
8074     case CPP_COLON:
8075       return MTIK_INSERT_AFTER_PREV;
8076 
8077       /* Other kinds of token don't get fix-it hints.  */
8078     default:
8079       return MTIK_IMPOSSIBLE;
8080     }
8081 }
8082 
8083 /* Given RICHLOC, a location for a diagnostic describing a missing token
8084    of kind TOKEN_TYPE, potentially add a fix-it hint suggesting the
8085    insertion of the token.
8086 
8087    The location of the attempted fix-it hint depends on TOKEN_TYPE:
8088    it will either be:
8089      (a) immediately after PREV_TOKEN_LOC, or
8090 
8091      (b) immediately before the primary location within RICHLOC (taken to
8092 	 be that of the token following where the token was expected).
8093 
8094    If we manage to add a fix-it hint, then the location of the
8095    fix-it hint is likely to be more useful as the primary location
8096    of the diagnostic than that of the following token, so we swap
8097    these locations.
8098 
8099    For example, given this bogus code:
8100        123456789012345678901234567890
8101    1 | int missing_semicolon (void)
8102    2 | {
8103    3 |   return 42
8104    4 | }
8105 
8106    we will emit:
8107 
8108      "expected ';' before '}'"
8109 
8110    RICHLOC's primary location is at the closing brace, so before "swapping"
8111    we would emit the error at line 4 column 1:
8112 
8113        123456789012345678901234567890
8114    3 |   return 42  |< fix-it hint emitted for this line
8115      |            ; |
8116    4 | }            |< "expected ';' before '}'" emitted at this line
8117      | ^            |
8118 
8119    It's more useful for the location of the diagnostic to be at the
8120    fix-it hint, so we swap the locations, so the primary location
8121    is at the fix-it hint, with the old primary location inserted
8122    as a secondary location, giving this, with the error at line 3
8123    column 12:
8124 
8125        123456789012345678901234567890
8126    3 |   return 42   |< "expected ';' before '}'" emitted at this line,
8127      |            ^  |   with fix-it hint
8128    4 |            ;  |
8129      | }             |< secondary range emitted here
8130      | ~             |.  */
8131 
8132 void
8133 maybe_suggest_missing_token_insertion (rich_location *richloc,
8134 				       enum cpp_ttype token_type,
8135 				       location_t prev_token_loc)
8136 {
8137   gcc_assert (richloc);
8138 
8139   enum missing_token_insertion_kind mtik
8140     = get_missing_token_insertion_kind (token_type);
8141 
8142   switch (mtik)
8143     {
8144     default:
8145       gcc_unreachable ();
8146       break;
8147 
8148     case MTIK_IMPOSSIBLE:
8149       return;
8150 
8151     case MTIK_INSERT_BEFORE_NEXT:
8152       /* Attempt to add the fix-it hint before the primary location
8153 	 of RICHLOC.  */
8154       richloc->add_fixit_insert_before (cpp_type2name (token_type, 0));
8155       break;
8156 
8157     case MTIK_INSERT_AFTER_PREV:
8158       /* Attempt to add the fix-it hint after PREV_TOKEN_LOC.  */
8159       richloc->add_fixit_insert_after (prev_token_loc,
8160 				       cpp_type2name (token_type, 0));
8161       break;
8162     }
8163 
8164   /* If we were successful, use the fix-it hint's location as the
8165      primary location within RICHLOC, adding the old primary location
8166      back as a secondary location.  */
8167   if (!richloc->seen_impossible_fixit_p ())
8168     {
8169       fixit_hint *hint = richloc->get_last_fixit_hint ();
8170       location_t hint_loc = hint->get_start_loc ();
8171       location_t old_loc = richloc->get_loc ();
8172 
8173       richloc->set_range (line_table, 0, hint_loc, true);
8174       richloc->add_range (old_loc, false);
8175     }
8176 }
8177 
8178 #if CHECKING_P
8179 
8180 namespace selftest {
8181 
8182 /* Verify that fold_for_warn on error_mark_node is safe.  */
8183 
8184 static void
8185 test_fold_for_warn ()
8186 {
8187   ASSERT_EQ (error_mark_node, fold_for_warn (error_mark_node));
8188 }
8189 
8190 /* Run all of the selftests within this file.  */
8191 
8192 static void
8193 c_common_c_tests ()
8194 {
8195   test_fold_for_warn ();
8196 }
8197 
8198 /* Run all of the tests within c-family.  */
8199 
8200 void
8201 c_family_tests (void)
8202 {
8203   c_common_c_tests ();
8204   c_format_c_tests ();
8205   c_pretty_print_c_tests ();
8206   c_spellcheck_cc_tests ();
8207 }
8208 
8209 } // namespace selftest
8210 
8211 #endif /* #if CHECKING_P */
8212 
8213 /* Attempt to locate a suitable location within FILE for a
8214    #include directive to be inserted before.  FILE should
8215    be a string from libcpp (pointer equality is used).
8216    LOC is the location of the relevant diagnostic.
8217 
8218    Attempt to return the location within FILE immediately
8219    after the last #include within that file, or the start of
8220    that file if it has no #include directives.
8221 
8222    Return UNKNOWN_LOCATION if no suitable location is found,
8223    or if an error occurs.  */
8224 
8225 static location_t
8226 try_to_locate_new_include_insertion_point (const char *file, location_t loc)
8227 {
8228   /* Locate the last ordinary map within FILE that ended with a #include.  */
8229   const line_map_ordinary *last_include_ord_map = NULL;
8230 
8231   /* ...and the next ordinary map within FILE after that one.  */
8232   const line_map_ordinary *last_ord_map_after_include = NULL;
8233 
8234   /* ...and the first ordinary map within FILE.  */
8235   const line_map_ordinary *first_ord_map_in_file = NULL;
8236 
8237   /*  Get ordinary map containing LOC (or its expansion).  */
8238   const line_map_ordinary *ord_map_for_loc = NULL;
8239   loc = linemap_resolve_location (line_table, loc, LRK_MACRO_EXPANSION_POINT,
8240 				  &ord_map_for_loc);
8241   gcc_assert (ord_map_for_loc);
8242 
8243   for (unsigned int i = 0; i < LINEMAPS_ORDINARY_USED (line_table); i++)
8244     {
8245       const line_map_ordinary *ord_map
8246 	= LINEMAPS_ORDINARY_MAP_AT (line_table, i);
8247 
8248       const line_map_ordinary *from = INCLUDED_FROM (line_table, ord_map);
8249       if (from)
8250 	if (from->to_file == file)
8251 	  {
8252 	    last_include_ord_map = from;
8253 	    last_ord_map_after_include = NULL;
8254 	  }
8255 
8256       if (ord_map->to_file == file)
8257 	{
8258 	  if (!first_ord_map_in_file)
8259 	    first_ord_map_in_file = ord_map;
8260 	  if (last_include_ord_map && !last_ord_map_after_include)
8261 	    last_ord_map_after_include = ord_map;
8262 	}
8263 
8264       /* Stop searching when reaching the ord_map containing LOC,
8265 	 as it makes no sense to provide fix-it hints that appear
8266 	 after the diagnostic in question.  */
8267       if (ord_map == ord_map_for_loc)
8268 	break;
8269     }
8270 
8271   /* Determine where to insert the #include.  */
8272   const line_map_ordinary *ord_map_for_insertion;
8273 
8274   /* We want the next ordmap in the file after the last one that's a
8275      #include, but failing that, the start of the file.  */
8276   if (last_ord_map_after_include)
8277     ord_map_for_insertion = last_ord_map_after_include;
8278   else
8279     ord_map_for_insertion = first_ord_map_in_file;
8280 
8281   if (!ord_map_for_insertion)
8282     return UNKNOWN_LOCATION;
8283 
8284   /* The "start_location" is column 0, meaning "the whole line".
8285      rich_location and edit_context can't cope with this, so use
8286      column 1 instead.  */
8287   location_t col_0 = ord_map_for_insertion->start_location;
8288   return linemap_position_for_loc_and_offset (line_table, col_0, 1);
8289 }
8290 
8291 /* A map from filenames to sets of headers added to them, for
8292    ensuring idempotency within maybe_add_include_fixit.  */
8293 
8294 /* The values within the map.  We need string comparison as there's
8295    no guarantee that two different diagnostics that are recommending
8296    adding e.g. "<stdio.h>" are using the same buffer.  */
8297 
8298 typedef hash_set <const char *, nofree_string_hash> per_file_includes_t;
8299 
8300 /* The map itself.  We don't need string comparison for the filename keys,
8301    as they come from libcpp.  */
8302 
8303 typedef hash_map <const char *, per_file_includes_t *> added_includes_t;
8304 static added_includes_t *added_includes;
8305 
8306 /* Attempt to add a fix-it hint to RICHLOC, adding "#include HEADER\n"
8307    in a suitable location within the file of RICHLOC's primary
8308    location.
8309 
8310    This function is idempotent: a header will be added at most once to
8311    any given file.  */
8312 
8313 void
8314 maybe_add_include_fixit (rich_location *richloc, const char *header)
8315 {
8316   location_t loc = richloc->get_loc ();
8317   const char *file = LOCATION_FILE (loc);
8318   if (!file)
8319     return;
8320 
8321   /* Idempotency: don't add the same header more than once to a given file.  */
8322   if (!added_includes)
8323     added_includes = new added_includes_t ();
8324   per_file_includes_t *&set = added_includes->get_or_insert (file);
8325   if (set)
8326     if (set->contains (header))
8327       /* ...then we've already added HEADER to that file.  */
8328       return;
8329   if (!set)
8330     set = new per_file_includes_t ();
8331   set->add (header);
8332 
8333   /* Attempt to locate a suitable place for the new directive.  */
8334   location_t include_insert_loc
8335     = try_to_locate_new_include_insertion_point (file, loc);
8336   if (include_insert_loc == UNKNOWN_LOCATION)
8337     return;
8338 
8339   char *text = xasprintf ("#include %s\n", header);
8340   richloc->add_fixit_insert_before (include_insert_loc, text);
8341   free (text);
8342 }
8343 
8344 #include "gt-c-family-c-common.h"
8345