1 /* Process declarations and variables for C++ compiler.
2 Copyright (C) 1988-2018 Free Software Foundation, Inc.
3 Hacked by Michael Tiemann (tiemann@cygnus.com)
4
5 This file is part of GCC.
6
7 GCC is free software; you can redistribute it and/or modify
8 it under the terms of the GNU General Public License as published by
9 the Free Software Foundation; either version 3, or (at your option)
10 any later version.
11
12 GCC is distributed in the hope that it will be useful,
13 but WITHOUT ANY WARRANTY; without even the implied warranty of
14 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
15 GNU General Public License for more details.
16
17 You should have received a copy of the GNU General Public License
18 along with GCC; see the file COPYING3. If not see
19 <http://www.gnu.org/licenses/>. */
20
21
22 /* Process declarations and symbol lookup for C++ front end.
23 Also constructs types; the standard scalar types at initialization,
24 and structure, union, array and enum types when they are declared. */
25
26 /* ??? not all decl nodes are given the most useful possible
27 line numbers. For example, the CONST_DECLs for enum values. */
28
29 #include "config.h"
30 #include "system.h"
31 #include "coretypes.h"
32 #include "memmodel.h"
33 #include "target.h"
34 #include "cp-tree.h"
35 #include "c-family/c-common.h"
36 #include "timevar.h"
37 #include "stringpool.h"
38 #include "cgraph.h"
39 #include "varasm.h"
40 #include "attribs.h"
41 #include "stor-layout.h"
42 #include "calls.h"
43 #include "decl.h"
44 #include "toplev.h"
45 #include "c-family/c-objc.h"
46 #include "c-family/c-pragma.h"
47 #include "dumpfile.h"
48 #include "intl.h"
49 #include "c-family/c-ada-spec.h"
50 #include "asan.h"
51
52 /* Id for dumping the raw trees. */
53 int raw_dump_id;
54
55 extern cpp_reader *parse_in;
56
57 /* This structure contains information about the initializations
58 and/or destructions required for a particular priority level. */
59 typedef struct priority_info_s {
60 /* Nonzero if there have been any initializations at this priority
61 throughout the translation unit. */
62 int initializations_p;
63 /* Nonzero if there have been any destructions at this priority
64 throughout the translation unit. */
65 int destructions_p;
66 } *priority_info;
67
68 static void mark_vtable_entries (tree);
69 static bool maybe_emit_vtables (tree);
70 static tree start_objects (int, int);
71 static void finish_objects (int, int, tree);
72 static tree start_static_storage_duration_function (unsigned);
73 static void finish_static_storage_duration_function (tree);
74 static priority_info get_priority_info (int);
75 static void do_static_initialization_or_destruction (tree, bool);
76 static void one_static_initialization_or_destruction (tree, tree, bool);
77 static void generate_ctor_or_dtor_function (bool, int, location_t *);
78 static int generate_ctor_and_dtor_functions_for_priority (splay_tree_node,
79 void *);
80 static tree prune_vars_needing_no_initialization (tree *);
81 static void write_out_vars (tree);
82 static void import_export_class (tree);
83 static tree get_guard_bits (tree);
84 static void determine_visibility_from_class (tree, tree);
85 static bool determine_hidden_inline (tree);
86 static void maybe_instantiate_decl (tree);
87
88 /* A list of static class variables. This is needed, because a
89 static class variable can be declared inside the class without
90 an initializer, and then initialized, statically, outside the class. */
91 static GTY(()) vec<tree, va_gc> *pending_statics;
92
93 /* A list of functions which were declared inline, but which we
94 may need to emit outline anyway. */
95 static GTY(()) vec<tree, va_gc> *deferred_fns;
96
97 /* A list of decls that use types with no linkage, which we need to make
98 sure are defined. */
99 static GTY(()) vec<tree, va_gc> *no_linkage_decls;
100
101 /* A vector of alternating decls and identifiers, where the latter
102 is to be an alias for the former if the former is defined. */
103 static GTY(()) vec<tree, va_gc> *mangling_aliases;
104
105 /* hash traits for declarations. Hashes single decls via
106 DECL_ASSEMBLER_NAME_RAW. */
107
108 struct mangled_decl_hash : ggc_remove <tree>
109 {
110 typedef tree value_type; /* A DECL. */
111 typedef tree compare_type; /* An identifier. */
112
hashmangled_decl_hash113 static hashval_t hash (const value_type decl)
114 {
115 return IDENTIFIER_HASH_VALUE (DECL_ASSEMBLER_NAME_RAW (decl));
116 }
equalmangled_decl_hash117 static bool equal (const value_type existing, compare_type candidate)
118 {
119 tree name = DECL_ASSEMBLER_NAME_RAW (existing);
120 return candidate == name;
121 }
122
mark_emptymangled_decl_hash123 static inline void mark_empty (value_type &p) {p = NULL_TREE;}
is_emptymangled_decl_hash124 static inline bool is_empty (value_type p) {return !p;}
125
is_deletedmangled_decl_hash126 static bool is_deleted (value_type e)
127 {
128 return e == reinterpret_cast <value_type> (1);
129 }
mark_deletedmangled_decl_hash130 static void mark_deleted (value_type &e)
131 {
132 e = reinterpret_cast <value_type> (1);
133 }
134 };
135
136 /* A hash table of decls keyed by mangled name. Used to figure out if
137 we need compatibility aliases. */
138 static GTY(()) hash_table<mangled_decl_hash> *mangled_decls;
139
140 /* Nonzero if we're done parsing and into end-of-file activities. */
141
142 int at_eof;
143
144 /* True if note_mangling_alias should enqueue mangling aliases for
145 later generation, rather than emitting them right away. */
146
147 bool defer_mangling_aliases = true;
148
149
150 /* Return a member function type (a METHOD_TYPE), given FNTYPE (a
151 FUNCTION_TYPE), CTYPE (class type), and QUALS (the cv-qualifiers
152 that apply to the function). */
153
154 tree
build_memfn_type(tree fntype,tree ctype,cp_cv_quals quals,cp_ref_qualifier rqual)155 build_memfn_type (tree fntype, tree ctype, cp_cv_quals quals,
156 cp_ref_qualifier rqual)
157 {
158 tree raises;
159 tree attrs;
160 int type_quals;
161 bool late_return_type_p;
162
163 if (fntype == error_mark_node || ctype == error_mark_node)
164 return error_mark_node;
165
166 gcc_assert (TREE_CODE (fntype) == FUNCTION_TYPE
167 || TREE_CODE (fntype) == METHOD_TYPE);
168
169 type_quals = quals & ~TYPE_QUAL_RESTRICT;
170 ctype = cp_build_qualified_type (ctype, type_quals);
171 raises = TYPE_RAISES_EXCEPTIONS (fntype);
172 attrs = TYPE_ATTRIBUTES (fntype);
173 late_return_type_p = TYPE_HAS_LATE_RETURN_TYPE (fntype);
174 fntype = build_method_type_directly (ctype, TREE_TYPE (fntype),
175 (TREE_CODE (fntype) == METHOD_TYPE
176 ? TREE_CHAIN (TYPE_ARG_TYPES (fntype))
177 : TYPE_ARG_TYPES (fntype)));
178 if (attrs)
179 fntype = cp_build_type_attribute_variant (fntype, attrs);
180 if (rqual)
181 fntype = build_ref_qualified_type (fntype, rqual);
182 if (raises)
183 fntype = build_exception_variant (fntype, raises);
184 if (late_return_type_p)
185 TYPE_HAS_LATE_RETURN_TYPE (fntype) = 1;
186
187 return fntype;
188 }
189
190 /* Return a variant of FNTYPE, a FUNCTION_TYPE or METHOD_TYPE, with its
191 return type changed to NEW_RET. */
192
193 tree
change_return_type(tree new_ret,tree fntype)194 change_return_type (tree new_ret, tree fntype)
195 {
196 tree newtype;
197 tree args = TYPE_ARG_TYPES (fntype);
198 tree raises = TYPE_RAISES_EXCEPTIONS (fntype);
199 tree attrs = TYPE_ATTRIBUTES (fntype);
200 bool late_return_type_p = TYPE_HAS_LATE_RETURN_TYPE (fntype);
201
202 if (new_ret == error_mark_node)
203 return fntype;
204
205 if (same_type_p (new_ret, TREE_TYPE (fntype)))
206 return fntype;
207
208 if (TREE_CODE (fntype) == FUNCTION_TYPE)
209 {
210 newtype = build_function_type (new_ret, args);
211 newtype = apply_memfn_quals (newtype,
212 type_memfn_quals (fntype),
213 type_memfn_rqual (fntype));
214 }
215 else
216 newtype = build_method_type_directly
217 (class_of_this_parm (fntype), new_ret, TREE_CHAIN (args));
218 if (FUNCTION_REF_QUALIFIED (fntype))
219 newtype = build_ref_qualified_type (newtype, type_memfn_rqual (fntype));
220 if (raises)
221 newtype = build_exception_variant (newtype, raises);
222 if (attrs)
223 newtype = cp_build_type_attribute_variant (newtype, attrs);
224 if (late_return_type_p)
225 TYPE_HAS_LATE_RETURN_TYPE (newtype) = 1;
226
227 return newtype;
228 }
229
230 /* Build a PARM_DECL of FN with NAME and TYPE, and set DECL_ARG_TYPE
231 appropriately. */
232
233 tree
cp_build_parm_decl(tree fn,tree name,tree type)234 cp_build_parm_decl (tree fn, tree name, tree type)
235 {
236 tree parm = build_decl (input_location,
237 PARM_DECL, name, type);
238 DECL_CONTEXT (parm) = fn;
239
240 /* DECL_ARG_TYPE is only used by the back end and the back end never
241 sees templates. */
242 if (!processing_template_decl)
243 DECL_ARG_TYPE (parm) = type_passed_as (type);
244
245 return parm;
246 }
247
248 /* Returns a PARM_DECL of FN for a parameter of the indicated TYPE, with the
249 indicated NAME. */
250
251 tree
build_artificial_parm(tree fn,tree name,tree type)252 build_artificial_parm (tree fn, tree name, tree type)
253 {
254 tree parm = cp_build_parm_decl (fn, name, type);
255 DECL_ARTIFICIAL (parm) = 1;
256 /* All our artificial parms are implicitly `const'; they cannot be
257 assigned to. */
258 TREE_READONLY (parm) = 1;
259 return parm;
260 }
261
262 /* Constructors for types with virtual baseclasses need an "in-charge" flag
263 saying whether this constructor is responsible for initialization of
264 virtual baseclasses or not. All destructors also need this "in-charge"
265 flag, which additionally determines whether or not the destructor should
266 free the memory for the object.
267
268 This function adds the "in-charge" flag to member function FN if
269 appropriate. It is called from grokclassfn and tsubst.
270 FN must be either a constructor or destructor.
271
272 The in-charge flag follows the 'this' parameter, and is followed by the
273 VTT parm (if any), then the user-written parms. */
274
275 void
maybe_retrofit_in_chrg(tree fn)276 maybe_retrofit_in_chrg (tree fn)
277 {
278 tree basetype, arg_types, parms, parm, fntype;
279
280 /* If we've already add the in-charge parameter don't do it again. */
281 if (DECL_HAS_IN_CHARGE_PARM_P (fn))
282 return;
283
284 /* When processing templates we can't know, in general, whether or
285 not we're going to have virtual baseclasses. */
286 if (processing_template_decl)
287 return;
288
289 /* We don't need an in-charge parameter for constructors that don't
290 have virtual bases. */
291 if (DECL_CONSTRUCTOR_P (fn)
292 && !CLASSTYPE_VBASECLASSES (DECL_CONTEXT (fn)))
293 return;
294
295 arg_types = TYPE_ARG_TYPES (TREE_TYPE (fn));
296 basetype = TREE_TYPE (TREE_VALUE (arg_types));
297 arg_types = TREE_CHAIN (arg_types);
298
299 parms = DECL_CHAIN (DECL_ARGUMENTS (fn));
300
301 /* If this is a subobject constructor or destructor, our caller will
302 pass us a pointer to our VTT. */
303 if (CLASSTYPE_VBASECLASSES (DECL_CONTEXT (fn)))
304 {
305 parm = build_artificial_parm (fn, vtt_parm_identifier, vtt_parm_type);
306
307 /* First add it to DECL_ARGUMENTS between 'this' and the real args... */
308 DECL_CHAIN (parm) = parms;
309 parms = parm;
310
311 /* ...and then to TYPE_ARG_TYPES. */
312 arg_types = hash_tree_chain (vtt_parm_type, arg_types);
313
314 DECL_HAS_VTT_PARM_P (fn) = 1;
315 }
316
317 /* Then add the in-charge parm (before the VTT parm). */
318 parm = build_artificial_parm (fn, in_charge_identifier, integer_type_node);
319 DECL_CHAIN (parm) = parms;
320 parms = parm;
321 arg_types = hash_tree_chain (integer_type_node, arg_types);
322
323 /* Insert our new parameter(s) into the list. */
324 DECL_CHAIN (DECL_ARGUMENTS (fn)) = parms;
325
326 /* And rebuild the function type. */
327 fntype = build_method_type_directly (basetype, TREE_TYPE (TREE_TYPE (fn)),
328 arg_types);
329 if (TYPE_RAISES_EXCEPTIONS (TREE_TYPE (fn)))
330 fntype = build_exception_variant (fntype,
331 TYPE_RAISES_EXCEPTIONS (TREE_TYPE (fn)));
332 if (TYPE_ATTRIBUTES (TREE_TYPE (fn)))
333 fntype = (cp_build_type_attribute_variant
334 (fntype, TYPE_ATTRIBUTES (TREE_TYPE (fn))));
335 TREE_TYPE (fn) = fntype;
336
337 /* Now we've got the in-charge parameter. */
338 DECL_HAS_IN_CHARGE_PARM_P (fn) = 1;
339 }
340
341 /* Classes overload their constituent function names automatically.
342 When a function name is declared in a record structure,
343 its name is changed to it overloaded name. Since names for
344 constructors and destructors can conflict, we place a leading
345 '$' for destructors.
346
347 CNAME is the name of the class we are grokking for.
348
349 FUNCTION is a FUNCTION_DECL. It was created by `grokdeclarator'.
350
351 FLAGS contains bits saying what's special about today's
352 arguments. DTOR_FLAG == DESTRUCTOR.
353
354 If FUNCTION is a destructor, then we must add the `auto-delete' field
355 as a second parameter. There is some hair associated with the fact
356 that we must "declare" this variable in the manner consistent with the
357 way the rest of the arguments were declared.
358
359 QUALS are the qualifiers for the this pointer. */
360
361 void
grokclassfn(tree ctype,tree function,enum overload_flags flags)362 grokclassfn (tree ctype, tree function, enum overload_flags flags)
363 {
364 tree fn_name = DECL_NAME (function);
365
366 /* Even within an `extern "C"' block, members get C++ linkage. See
367 [dcl.link] for details. */
368 SET_DECL_LANGUAGE (function, lang_cplusplus);
369
370 if (fn_name == NULL_TREE)
371 {
372 error ("name missing for member function");
373 fn_name = get_identifier ("<anonymous>");
374 DECL_NAME (function) = fn_name;
375 }
376
377 DECL_CONTEXT (function) = ctype;
378
379 if (flags == DTOR_FLAG)
380 DECL_CXX_DESTRUCTOR_P (function) = 1;
381
382 if (flags == DTOR_FLAG || DECL_CONSTRUCTOR_P (function))
383 maybe_retrofit_in_chrg (function);
384 }
385
386 /* Create an ARRAY_REF, checking for the user doing things backwards
387 along the way. DECLTYPE_P is for N3276, as in the parser. */
388
389 tree
grok_array_decl(location_t loc,tree array_expr,tree index_exp,bool decltype_p)390 grok_array_decl (location_t loc, tree array_expr, tree index_exp,
391 bool decltype_p)
392 {
393 tree type;
394 tree expr;
395 tree orig_array_expr = array_expr;
396 tree orig_index_exp = index_exp;
397 tree overload = NULL_TREE;
398
399 if (error_operand_p (array_expr) || error_operand_p (index_exp))
400 return error_mark_node;
401
402 if (processing_template_decl)
403 {
404 if (type_dependent_expression_p (array_expr)
405 || type_dependent_expression_p (index_exp))
406 return build_min_nt_loc (loc, ARRAY_REF, array_expr, index_exp,
407 NULL_TREE, NULL_TREE);
408 array_expr = build_non_dependent_expr (array_expr);
409 index_exp = build_non_dependent_expr (index_exp);
410 }
411
412 type = TREE_TYPE (array_expr);
413 gcc_assert (type);
414 type = non_reference (type);
415
416 /* If they have an `operator[]', use that. */
417 if (MAYBE_CLASS_TYPE_P (type) || MAYBE_CLASS_TYPE_P (TREE_TYPE (index_exp)))
418 {
419 tsubst_flags_t complain = tf_warning_or_error;
420 if (decltype_p)
421 complain |= tf_decltype;
422 expr = build_new_op (loc, ARRAY_REF, LOOKUP_NORMAL, array_expr,
423 index_exp, NULL_TREE, &overload, complain);
424 }
425 else
426 {
427 tree p1, p2, i1, i2;
428
429 /* Otherwise, create an ARRAY_REF for a pointer or array type.
430 It is a little-known fact that, if `a' is an array and `i' is
431 an int, you can write `i[a]', which means the same thing as
432 `a[i]'. */
433 if (TREE_CODE (type) == ARRAY_TYPE || VECTOR_TYPE_P (type))
434 p1 = array_expr;
435 else
436 p1 = build_expr_type_conversion (WANT_POINTER, array_expr, false);
437
438 if (TREE_CODE (TREE_TYPE (index_exp)) == ARRAY_TYPE)
439 p2 = index_exp;
440 else
441 p2 = build_expr_type_conversion (WANT_POINTER, index_exp, false);
442
443 i1 = build_expr_type_conversion (WANT_INT | WANT_ENUM, array_expr,
444 false);
445 i2 = build_expr_type_conversion (WANT_INT | WANT_ENUM, index_exp,
446 false);
447
448 if ((p1 && i2) && (i1 && p2))
449 error ("ambiguous conversion for array subscript");
450
451 if (p1 && i2)
452 array_expr = p1, index_exp = i2;
453 else if (i1 && p2)
454 array_expr = p2, index_exp = i1;
455 else
456 {
457 error ("invalid types %<%T[%T]%> for array subscript",
458 type, TREE_TYPE (index_exp));
459 return error_mark_node;
460 }
461
462 if (array_expr == error_mark_node || index_exp == error_mark_node)
463 error ("ambiguous conversion for array subscript");
464
465 if (TREE_CODE (TREE_TYPE (array_expr)) == POINTER_TYPE)
466 array_expr = mark_rvalue_use (array_expr);
467 else
468 array_expr = mark_lvalue_use_nonread (array_expr);
469 index_exp = mark_rvalue_use (index_exp);
470 expr = build_array_ref (input_location, array_expr, index_exp);
471 }
472 if (processing_template_decl && expr != error_mark_node)
473 {
474 if (overload != NULL_TREE)
475 return (build_min_non_dep_op_overload
476 (ARRAY_REF, expr, overload, orig_array_expr, orig_index_exp));
477
478 return build_min_non_dep (ARRAY_REF, expr, orig_array_expr, orig_index_exp,
479 NULL_TREE, NULL_TREE);
480 }
481 return expr;
482 }
483
484 /* Given the cast expression EXP, checking out its validity. Either return
485 an error_mark_node if there was an unavoidable error, return a cast to
486 void for trying to delete a pointer w/ the value 0, or return the
487 call to delete. If DOING_VEC is true, we handle things differently
488 for doing an array delete.
489 Implements ARM $5.3.4. This is called from the parser. */
490
491 tree
delete_sanity(tree exp,tree size,bool doing_vec,int use_global_delete,tsubst_flags_t complain)492 delete_sanity (tree exp, tree size, bool doing_vec, int use_global_delete,
493 tsubst_flags_t complain)
494 {
495 tree t, type;
496
497 if (exp == error_mark_node)
498 return exp;
499
500 if (processing_template_decl)
501 {
502 t = build_min (DELETE_EXPR, void_type_node, exp, size);
503 DELETE_EXPR_USE_GLOBAL (t) = use_global_delete;
504 DELETE_EXPR_USE_VEC (t) = doing_vec;
505 TREE_SIDE_EFFECTS (t) = 1;
506 return t;
507 }
508
509 /* An array can't have been allocated by new, so complain. */
510 if (TREE_CODE (TREE_TYPE (exp)) == ARRAY_TYPE)
511 warning (0, "deleting array %q#E", exp);
512
513 t = build_expr_type_conversion (WANT_POINTER, exp, true);
514
515 if (t == NULL_TREE || t == error_mark_node)
516 {
517 error ("type %q#T argument given to %<delete%>, expected pointer",
518 TREE_TYPE (exp));
519 return error_mark_node;
520 }
521
522 type = TREE_TYPE (t);
523
524 /* As of Valley Forge, you can delete a pointer to const. */
525
526 /* You can't delete functions. */
527 if (TREE_CODE (TREE_TYPE (type)) == FUNCTION_TYPE)
528 {
529 error ("cannot delete a function. Only pointer-to-objects are "
530 "valid arguments to %<delete%>");
531 return error_mark_node;
532 }
533
534 /* Deleting ptr to void is undefined behavior [expr.delete/3]. */
535 if (VOID_TYPE_P (TREE_TYPE (type)))
536 {
537 warning (OPT_Wdelete_incomplete, "deleting %qT is undefined", type);
538 doing_vec = 0;
539 }
540
541 /* Deleting a pointer with the value zero is valid and has no effect. */
542 if (integer_zerop (t))
543 return build1 (NOP_EXPR, void_type_node, t);
544
545 if (doing_vec)
546 return build_vec_delete (t, /*maxindex=*/NULL_TREE,
547 sfk_deleting_destructor,
548 use_global_delete, complain);
549 else
550 return build_delete (type, t, sfk_deleting_destructor,
551 LOOKUP_NORMAL, use_global_delete,
552 complain);
553 }
554
555 /* Report an error if the indicated template declaration is not the
556 sort of thing that should be a member template. */
557
558 void
check_member_template(tree tmpl)559 check_member_template (tree tmpl)
560 {
561 tree decl;
562
563 gcc_assert (TREE_CODE (tmpl) == TEMPLATE_DECL);
564 decl = DECL_TEMPLATE_RESULT (tmpl);
565
566 if (TREE_CODE (decl) == FUNCTION_DECL
567 || DECL_ALIAS_TEMPLATE_P (tmpl)
568 || (TREE_CODE (decl) == TYPE_DECL
569 && MAYBE_CLASS_TYPE_P (TREE_TYPE (decl))))
570 {
571 /* The parser rejects template declarations in local classes
572 (with the exception of generic lambdas). */
573 gcc_assert (!current_function_decl || LAMBDA_FUNCTION_P (decl));
574 /* The parser rejects any use of virtual in a function template. */
575 gcc_assert (!(TREE_CODE (decl) == FUNCTION_DECL
576 && DECL_VIRTUAL_P (decl)));
577
578 /* The debug-information generating code doesn't know what to do
579 with member templates. */
580 DECL_IGNORED_P (tmpl) = 1;
581 }
582 else if (variable_template_p (tmpl))
583 /* OK */;
584 else
585 error ("template declaration of %q#D", decl);
586 }
587
588 /* Sanity check: report error if this function FUNCTION is not
589 really a member of the class (CTYPE) it is supposed to belong to.
590 TEMPLATE_PARMS is used to specify the template parameters of a member
591 template passed as FUNCTION_DECL. If the member template is passed as a
592 TEMPLATE_DECL, it can be NULL since the parameters can be extracted
593 from the declaration. If the function is not a function template, it
594 must be NULL.
595 It returns the original declaration for the function, NULL_TREE if
596 no declaration was found, error_mark_node if an error was emitted. */
597
598 tree
check_classfn(tree ctype,tree function,tree template_parms)599 check_classfn (tree ctype, tree function, tree template_parms)
600 {
601 if (DECL_USE_TEMPLATE (function)
602 && !(TREE_CODE (function) == TEMPLATE_DECL
603 && DECL_TEMPLATE_SPECIALIZATION (function))
604 && DECL_MEMBER_TEMPLATE_P (DECL_TI_TEMPLATE (function)))
605 /* Since this is a specialization of a member template,
606 we're not going to find the declaration in the class.
607 For example, in:
608
609 struct S { template <typename T> void f(T); };
610 template <> void S::f(int);
611
612 we're not going to find `S::f(int)', but there's no
613 reason we should, either. We let our callers know we didn't
614 find the method, but we don't complain. */
615 return NULL_TREE;
616
617 /* Basic sanity check: for a template function, the template parameters
618 either were not passed, or they are the same of DECL_TEMPLATE_PARMS. */
619 if (TREE_CODE (function) == TEMPLATE_DECL)
620 {
621 if (template_parms
622 && !comp_template_parms (template_parms,
623 DECL_TEMPLATE_PARMS (function)))
624 {
625 error ("template parameter lists provided don%'t match the "
626 "template parameters of %qD", function);
627 return error_mark_node;
628 }
629 template_parms = DECL_TEMPLATE_PARMS (function);
630 }
631
632 /* OK, is this a definition of a member template? */
633 bool is_template = (template_parms != NULL_TREE);
634
635 /* [temp.mem]
636
637 A destructor shall not be a member template. */
638 if (DECL_DESTRUCTOR_P (function) && is_template)
639 {
640 error ("destructor %qD declared as member template", function);
641 return error_mark_node;
642 }
643
644 /* We must enter the scope here, because conversion operators are
645 named by target type, and type equivalence relies on typenames
646 resolving within the scope of CTYPE. */
647 tree pushed_scope = push_scope (ctype);
648 tree matched = NULL_TREE;
649 tree fns = get_class_binding (ctype, DECL_NAME (function));
650
651 for (ovl_iterator iter (fns); !matched && iter; ++iter)
652 {
653 tree fndecl = *iter;
654
655 /* A member template definition only matches a member template
656 declaration. */
657 if (is_template != (TREE_CODE (fndecl) == TEMPLATE_DECL))
658 continue;
659
660 if (!DECL_DECLARES_FUNCTION_P (fndecl))
661 continue;
662
663 tree p1 = TYPE_ARG_TYPES (TREE_TYPE (function));
664 tree p2 = TYPE_ARG_TYPES (TREE_TYPE (fndecl));
665
666 /* We cannot simply call decls_match because this doesn't work
667 for static member functions that are pretending to be
668 methods, and because the name may have been changed by
669 asm("new_name"). */
670
671 /* Get rid of the this parameter on functions that become
672 static. */
673 if (DECL_STATIC_FUNCTION_P (fndecl)
674 && TREE_CODE (TREE_TYPE (function)) == METHOD_TYPE)
675 p1 = TREE_CHAIN (p1);
676
677 /* ref-qualifier or absence of same must match. */
678 if (type_memfn_rqual (TREE_TYPE (function))
679 != type_memfn_rqual (TREE_TYPE (fndecl)))
680 continue;
681
682 // Include constraints in the match.
683 tree c1 = get_constraints (function);
684 tree c2 = get_constraints (fndecl);
685
686 /* While finding a match, same types and params are not enough
687 if the function is versioned. Also check version ("target")
688 attributes. */
689 if (same_type_p (TREE_TYPE (TREE_TYPE (function)),
690 TREE_TYPE (TREE_TYPE (fndecl)))
691 && compparms (p1, p2)
692 && !targetm.target_option.function_versions (function, fndecl)
693 && (!is_template
694 || comp_template_parms (template_parms,
695 DECL_TEMPLATE_PARMS (fndecl)))
696 && equivalent_constraints (c1, c2)
697 && (DECL_TEMPLATE_SPECIALIZATION (function)
698 == DECL_TEMPLATE_SPECIALIZATION (fndecl))
699 && (!DECL_TEMPLATE_SPECIALIZATION (function)
700 || (DECL_TI_TEMPLATE (function) == DECL_TI_TEMPLATE (fndecl))))
701 matched = fndecl;
702 }
703
704 if (!matched)
705 {
706 if (!COMPLETE_TYPE_P (ctype))
707 cxx_incomplete_type_error (function, ctype);
708 else
709 {
710 if (DECL_CONV_FN_P (function))
711 fns = get_class_binding (ctype, conv_op_identifier);
712
713 error_at (DECL_SOURCE_LOCATION (function),
714 "no declaration matches %q#D", function);
715 if (fns)
716 print_candidates (fns);
717 else if (DECL_CONV_FN_P (function))
718 inform (DECL_SOURCE_LOCATION (function),
719 "no conversion operators declared");
720 else
721 inform (DECL_SOURCE_LOCATION (function),
722 "no functions named %qD", function);
723 inform (DECL_SOURCE_LOCATION (TYPE_NAME (ctype)),
724 "%#qT defined here", ctype);
725 }
726 matched = error_mark_node;
727 }
728
729 if (pushed_scope)
730 pop_scope (pushed_scope);
731
732 return matched;
733 }
734
735 /* DECL is a function with vague linkage. Remember it so that at the
736 end of the translation unit we can decide whether or not to emit
737 it. */
738
739 void
note_vague_linkage_fn(tree decl)740 note_vague_linkage_fn (tree decl)
741 {
742 if (processing_template_decl)
743 return;
744
745 DECL_DEFER_OUTPUT (decl) = 1;
746 vec_safe_push (deferred_fns, decl);
747 }
748
749 /* As above, but for variable template instantiations. */
750
751 void
note_variable_template_instantiation(tree decl)752 note_variable_template_instantiation (tree decl)
753 {
754 vec_safe_push (pending_statics, decl);
755 }
756
757 /* We have just processed the DECL, which is a static data member.
758 The other parameters are as for cp_finish_decl. */
759
760 void
finish_static_data_member_decl(tree decl,tree init,bool init_const_expr_p,tree asmspec_tree,int flags)761 finish_static_data_member_decl (tree decl,
762 tree init, bool init_const_expr_p,
763 tree asmspec_tree,
764 int flags)
765 {
766 DECL_CONTEXT (decl) = current_class_type;
767
768 /* We cannot call pushdecl here, because that would fill in the
769 TREE_CHAIN of our decl. Instead, we modify cp_finish_decl to do
770 the right thing, namely, to put this decl out straight away. */
771
772 if (! processing_template_decl)
773 vec_safe_push (pending_statics, decl);
774
775 if (LOCAL_CLASS_P (current_class_type)
776 /* We already complained about the template definition. */
777 && !DECL_TEMPLATE_INSTANTIATION (decl))
778 permerror (input_location, "local class %q#T shall not have static data member %q#D",
779 current_class_type, decl);
780 else
781 for (tree t = current_class_type; TYPE_P (t);
782 t = CP_TYPE_CONTEXT (t))
783 if (TYPE_UNNAMED_P (t))
784 {
785 if (permerror (DECL_SOURCE_LOCATION (decl),
786 "static data member %qD in unnamed class", decl))
787 inform (DECL_SOURCE_LOCATION (TYPE_NAME (t)),
788 "unnamed class defined here");
789 break;
790 }
791
792 DECL_IN_AGGR_P (decl) = 1;
793
794 if (TREE_CODE (TREE_TYPE (decl)) == ARRAY_TYPE
795 && TYPE_DOMAIN (TREE_TYPE (decl)) == NULL_TREE)
796 SET_VAR_HAD_UNKNOWN_BOUND (decl);
797
798 if (init)
799 {
800 /* Similarly to start_decl_1, we want to complete the type in order
801 to do the right thing in cp_apply_type_quals_to_decl, possibly
802 clear TYPE_QUAL_CONST (c++/65579). */
803 tree type = TREE_TYPE (decl) = complete_type (TREE_TYPE (decl));
804 cp_apply_type_quals_to_decl (cp_type_quals (type), decl);
805 }
806
807 cp_finish_decl (decl, init, init_const_expr_p, asmspec_tree, flags);
808 }
809
810 /* DECLARATOR and DECLSPECS correspond to a class member. The other
811 parameters are as for cp_finish_decl. Return the DECL for the
812 class member declared. */
813
814 tree
grokfield(const cp_declarator * declarator,cp_decl_specifier_seq * declspecs,tree init,bool init_const_expr_p,tree asmspec_tree,tree attrlist)815 grokfield (const cp_declarator *declarator,
816 cp_decl_specifier_seq *declspecs,
817 tree init, bool init_const_expr_p,
818 tree asmspec_tree,
819 tree attrlist)
820 {
821 tree value;
822 const char *asmspec = 0;
823 int flags;
824 tree name;
825
826 if (init
827 && TREE_CODE (init) == TREE_LIST
828 && TREE_VALUE (init) == error_mark_node
829 && TREE_CHAIN (init) == NULL_TREE)
830 init = NULL_TREE;
831
832 value = grokdeclarator (declarator, declspecs, FIELD, init != 0, &attrlist);
833 if (! value || value == error_mark_node)
834 /* friend or constructor went bad. */
835 return error_mark_node;
836 if (TREE_TYPE (value) == error_mark_node)
837 return value;
838
839 if (TREE_CODE (value) == TYPE_DECL && init)
840 {
841 error ("typedef %qD is initialized (use decltype instead)", value);
842 init = NULL_TREE;
843 }
844
845 /* Pass friendly classes back. */
846 if (value == void_type_node)
847 return value;
848
849
850 name = DECL_NAME (value);
851
852 if (name != NULL_TREE)
853 {
854 if (TREE_CODE (name) == TEMPLATE_ID_EXPR)
855 {
856 error ("explicit template argument list not allowed");
857 return error_mark_node;
858 }
859
860 if (IDENTIFIER_POINTER (name)[0] == '_'
861 && id_equal (name, "_vptr"))
862 error ("member %qD conflicts with virtual function table field name",
863 value);
864 }
865
866 /* Stash away type declarations. */
867 if (TREE_CODE (value) == TYPE_DECL)
868 {
869 DECL_NONLOCAL (value) = 1;
870 DECL_CONTEXT (value) = current_class_type;
871
872 if (attrlist)
873 {
874 int attrflags = 0;
875
876 /* If this is a typedef that names the class for linkage purposes
877 (7.1.3p8), apply any attributes directly to the type. */
878 if (OVERLOAD_TYPE_P (TREE_TYPE (value))
879 && value == TYPE_NAME (TYPE_MAIN_VARIANT (TREE_TYPE (value))))
880 attrflags = ATTR_FLAG_TYPE_IN_PLACE;
881
882 cplus_decl_attributes (&value, attrlist, attrflags);
883 }
884
885 if (decl_spec_seq_has_spec_p (declspecs, ds_typedef)
886 && TREE_TYPE (value) != error_mark_node
887 && TYPE_NAME (TYPE_MAIN_VARIANT (TREE_TYPE (value))) != value)
888 set_underlying_type (value);
889
890 /* It's important that push_template_decl below follows
891 set_underlying_type above so that the created template
892 carries the properly set type of VALUE. */
893 if (processing_template_decl)
894 value = push_template_decl (value);
895
896 record_locally_defined_typedef (value);
897 return value;
898 }
899
900 int friendp = decl_spec_seq_has_spec_p (declspecs, ds_friend);
901
902 if (!friendp && DECL_IN_AGGR_P (value))
903 {
904 error ("%qD is already defined in %qT", value, DECL_CONTEXT (value));
905 return void_type_node;
906 }
907
908 if (asmspec_tree && asmspec_tree != error_mark_node)
909 asmspec = TREE_STRING_POINTER (asmspec_tree);
910
911 if (init)
912 {
913 if (TREE_CODE (value) == FUNCTION_DECL)
914 {
915 if (init == ridpointers[(int)RID_DELETE])
916 {
917 if (friendp && decl_defined_p (value))
918 {
919 error ("redefinition of %q#D", value);
920 inform (DECL_SOURCE_LOCATION (value),
921 "%q#D previously defined here", value);
922 }
923 else
924 {
925 DECL_DELETED_FN (value) = 1;
926 DECL_DECLARED_INLINE_P (value) = 1;
927 DECL_INITIAL (value) = error_mark_node;
928 }
929 }
930 else if (init == ridpointers[(int)RID_DEFAULT])
931 {
932 if (defaultable_fn_check (value))
933 {
934 DECL_DEFAULTED_FN (value) = 1;
935 DECL_INITIALIZED_IN_CLASS_P (value) = 1;
936 DECL_DECLARED_INLINE_P (value) = 1;
937 }
938 }
939 else if (TREE_CODE (init) == DEFAULT_ARG)
940 error ("invalid initializer for member function %qD", value);
941 else if (TREE_CODE (TREE_TYPE (value)) == METHOD_TYPE)
942 {
943 if (integer_zerop (init))
944 DECL_PURE_VIRTUAL_P (value) = 1;
945 else if (error_operand_p (init))
946 ; /* An error has already been reported. */
947 else
948 error ("invalid initializer for member function %qD",
949 value);
950 }
951 else
952 {
953 gcc_assert (TREE_CODE (TREE_TYPE (value)) == FUNCTION_TYPE);
954 if (friendp)
955 error ("initializer specified for friend function %qD",
956 value);
957 else
958 error ("initializer specified for static member function %qD",
959 value);
960 }
961 }
962 else if (TREE_CODE (value) == FIELD_DECL)
963 /* C++11 NSDMI, keep going. */;
964 else if (!VAR_P (value))
965 gcc_unreachable ();
966 }
967
968 /* Pass friend decls back. */
969 if ((TREE_CODE (value) == FUNCTION_DECL
970 || TREE_CODE (value) == TEMPLATE_DECL)
971 && DECL_CONTEXT (value) != current_class_type)
972 return value;
973
974 /* Need to set this before push_template_decl. */
975 if (VAR_P (value))
976 DECL_CONTEXT (value) = current_class_type;
977
978 if (processing_template_decl && VAR_OR_FUNCTION_DECL_P (value))
979 {
980 value = push_template_decl (value);
981 if (error_operand_p (value))
982 return error_mark_node;
983 }
984
985 if (attrlist)
986 cplus_decl_attributes (&value, attrlist, 0);
987
988 if (init && DIRECT_LIST_INIT_P (init))
989 flags = LOOKUP_NORMAL;
990 else
991 flags = LOOKUP_IMPLICIT;
992
993 switch (TREE_CODE (value))
994 {
995 case VAR_DECL:
996 finish_static_data_member_decl (value, init, init_const_expr_p,
997 asmspec_tree, flags);
998 return value;
999
1000 case FIELD_DECL:
1001 if (asmspec)
1002 error ("%<asm%> specifiers are not permitted on non-static data members");
1003 if (DECL_INITIAL (value) == error_mark_node)
1004 init = error_mark_node;
1005 cp_finish_decl (value, init, /*init_const_expr_p=*/false,
1006 NULL_TREE, flags);
1007 DECL_IN_AGGR_P (value) = 1;
1008 return value;
1009
1010 case FUNCTION_DECL:
1011 if (asmspec)
1012 set_user_assembler_name (value, asmspec);
1013
1014 cp_finish_decl (value,
1015 /*init=*/NULL_TREE,
1016 /*init_const_expr_p=*/false,
1017 asmspec_tree, flags);
1018
1019 /* Pass friends back this way. */
1020 if (DECL_FRIEND_P (value))
1021 return void_type_node;
1022
1023 DECL_IN_AGGR_P (value) = 1;
1024 return value;
1025
1026 default:
1027 gcc_unreachable ();
1028 }
1029 return NULL_TREE;
1030 }
1031
1032 /* Like `grokfield', but for bitfields.
1033 WIDTH is the width of the bitfield, a constant expression.
1034 The other parameters are as for grokfield. */
1035
1036 tree
grokbitfield(const cp_declarator * declarator,cp_decl_specifier_seq * declspecs,tree width,tree init,tree attrlist)1037 grokbitfield (const cp_declarator *declarator,
1038 cp_decl_specifier_seq *declspecs, tree width, tree init,
1039 tree attrlist)
1040 {
1041 tree value = grokdeclarator (declarator, declspecs, BITFIELD,
1042 init != NULL_TREE, &attrlist);
1043
1044 if (value == error_mark_node)
1045 return NULL_TREE; /* friends went bad. */
1046 if (TREE_TYPE (value) == error_mark_node)
1047 return value;
1048
1049 /* Pass friendly classes back. */
1050 if (VOID_TYPE_P (value))
1051 return void_type_node;
1052
1053 if (!INTEGRAL_OR_ENUMERATION_TYPE_P (TREE_TYPE (value))
1054 && (POINTER_TYPE_P (value)
1055 || !dependent_type_p (TREE_TYPE (value))))
1056 {
1057 error ("bit-field %qD with non-integral type", value);
1058 return error_mark_node;
1059 }
1060
1061 if (TREE_CODE (value) == TYPE_DECL)
1062 {
1063 error ("cannot declare %qD to be a bit-field type", value);
1064 return NULL_TREE;
1065 }
1066
1067 /* Usually, finish_struct_1 catches bitfields with invalid types.
1068 But, in the case of bitfields with function type, we confuse
1069 ourselves into thinking they are member functions, so we must
1070 check here. */
1071 if (TREE_CODE (value) == FUNCTION_DECL)
1072 {
1073 error ("cannot declare bit-field %qD with function type",
1074 DECL_NAME (value));
1075 return NULL_TREE;
1076 }
1077
1078 if (width && TYPE_WARN_IF_NOT_ALIGN (TREE_TYPE (value)))
1079 {
1080 error ("cannot declare bit-field %qD with %<warn_if_not_aligned%> type",
1081 DECL_NAME (value));
1082 return NULL_TREE;
1083 }
1084
1085 if (DECL_IN_AGGR_P (value))
1086 {
1087 error ("%qD is already defined in the class %qT", value,
1088 DECL_CONTEXT (value));
1089 return void_type_node;
1090 }
1091
1092 if (TREE_STATIC (value))
1093 {
1094 error ("static member %qD cannot be a bit-field", value);
1095 return NULL_TREE;
1096 }
1097
1098 int flags = LOOKUP_IMPLICIT;
1099 if (init && DIRECT_LIST_INIT_P (init))
1100 flags = LOOKUP_NORMAL;
1101 cp_finish_decl (value, init, false, NULL_TREE, flags);
1102
1103 if (width != error_mark_node)
1104 {
1105 /* The width must be an integer type. */
1106 if (!type_dependent_expression_p (width)
1107 && !INTEGRAL_OR_UNSCOPED_ENUMERATION_TYPE_P (TREE_TYPE (width)))
1108 error ("width of bit-field %qD has non-integral type %qT", value,
1109 TREE_TYPE (width));
1110 else
1111 {
1112 /* Temporarily stash the width in DECL_BIT_FIELD_REPRESENTATIVE.
1113 check_bitfield_decl picks it from there later and sets DECL_SIZE
1114 accordingly. */
1115 DECL_BIT_FIELD_REPRESENTATIVE (value) = width;
1116 SET_DECL_C_BIT_FIELD (value);
1117 }
1118 }
1119
1120 DECL_IN_AGGR_P (value) = 1;
1121
1122 if (attrlist)
1123 cplus_decl_attributes (&value, attrlist, /*flags=*/0);
1124
1125 return value;
1126 }
1127
1128
1129 /* Returns true iff ATTR is an attribute which needs to be applied at
1130 instantiation time rather than template definition time. */
1131
1132 static bool
is_late_template_attribute(tree attr,tree decl)1133 is_late_template_attribute (tree attr, tree decl)
1134 {
1135 tree name = get_attribute_name (attr);
1136 tree args = TREE_VALUE (attr);
1137 const struct attribute_spec *spec = lookup_attribute_spec (name);
1138 tree arg;
1139
1140 if (!spec)
1141 /* Unknown attribute. */
1142 return false;
1143
1144 /* Attribute weak handling wants to write out assembly right away. */
1145 if (is_attribute_p ("weak", name))
1146 return true;
1147
1148 /* Attributes used and unused are applied directly to typedefs for the
1149 benefit of maybe_warn_unused_local_typedefs. */
1150 if (TREE_CODE (decl) == TYPE_DECL
1151 && (is_attribute_p ("unused", name)
1152 || is_attribute_p ("used", name)))
1153 return false;
1154
1155 /* Attribute tls_model wants to modify the symtab. */
1156 if (is_attribute_p ("tls_model", name))
1157 return true;
1158
1159 /* #pragma omp declare simd attribute needs to be always deferred. */
1160 if (flag_openmp
1161 && is_attribute_p ("omp declare simd", name))
1162 return true;
1163
1164 /* An attribute pack is clearly dependent. */
1165 if (args && PACK_EXPANSION_P (args))
1166 return true;
1167
1168 /* If any of the arguments are dependent expressions, we can't evaluate
1169 the attribute until instantiation time. */
1170 for (arg = args; arg; arg = TREE_CHAIN (arg))
1171 {
1172 tree t = TREE_VALUE (arg);
1173
1174 /* If the first attribute argument is an identifier, only consider
1175 second and following arguments. Attributes like mode, format,
1176 cleanup and several target specific attributes aren't late
1177 just because they have an IDENTIFIER_NODE as first argument. */
1178 if (arg == args && attribute_takes_identifier_p (name)
1179 && identifier_p (t))
1180 continue;
1181
1182 if (value_dependent_expression_p (t)
1183 || type_dependent_expression_p (t))
1184 return true;
1185 }
1186
1187 if (TREE_CODE (decl) == TYPE_DECL
1188 || TYPE_P (decl)
1189 || spec->type_required)
1190 {
1191 tree type = TYPE_P (decl) ? decl : TREE_TYPE (decl);
1192
1193 /* We can't apply any attributes to a completely unknown type until
1194 instantiation time. */
1195 enum tree_code code = TREE_CODE (type);
1196 if (code == TEMPLATE_TYPE_PARM
1197 || code == BOUND_TEMPLATE_TEMPLATE_PARM
1198 || code == TYPENAME_TYPE)
1199 return true;
1200 /* Also defer most attributes on dependent types. This is not
1201 necessary in all cases, but is the better default. */
1202 else if (dependent_type_p (type)
1203 /* But some attributes specifically apply to templates. */
1204 && !is_attribute_p ("abi_tag", name)
1205 && !is_attribute_p ("deprecated", name)
1206 && !is_attribute_p ("visibility", name))
1207 return true;
1208 else
1209 return false;
1210 }
1211 else
1212 return false;
1213 }
1214
1215 /* ATTR_P is a list of attributes. Remove any attributes which need to be
1216 applied at instantiation time and return them. If IS_DEPENDENT is true,
1217 the declaration itself is dependent, so all attributes should be applied
1218 at instantiation time. */
1219
1220 static tree
splice_template_attributes(tree * attr_p,tree decl)1221 splice_template_attributes (tree *attr_p, tree decl)
1222 {
1223 tree *p = attr_p;
1224 tree late_attrs = NULL_TREE;
1225 tree *q = &late_attrs;
1226
1227 if (!p)
1228 return NULL_TREE;
1229
1230 for (; *p; )
1231 {
1232 if (is_late_template_attribute (*p, decl))
1233 {
1234 ATTR_IS_DEPENDENT (*p) = 1;
1235 *q = *p;
1236 *p = TREE_CHAIN (*p);
1237 q = &TREE_CHAIN (*q);
1238 *q = NULL_TREE;
1239 }
1240 else
1241 p = &TREE_CHAIN (*p);
1242 }
1243
1244 return late_attrs;
1245 }
1246
1247 /* Remove any late attributes from the list in ATTR_P and attach them to
1248 DECL_P. */
1249
1250 static void
save_template_attributes(tree * attr_p,tree * decl_p,int flags)1251 save_template_attributes (tree *attr_p, tree *decl_p, int flags)
1252 {
1253 tree *q;
1254
1255 if (attr_p && *attr_p == error_mark_node)
1256 return;
1257
1258 tree late_attrs = splice_template_attributes (attr_p, *decl_p);
1259 if (!late_attrs)
1260 return;
1261
1262 if (DECL_P (*decl_p))
1263 q = &DECL_ATTRIBUTES (*decl_p);
1264 else
1265 q = &TYPE_ATTRIBUTES (*decl_p);
1266
1267 tree old_attrs = *q;
1268
1269 /* Merge the late attributes at the beginning with the attribute
1270 list. */
1271 late_attrs = merge_attributes (late_attrs, *q);
1272 if (*q != late_attrs
1273 && !DECL_P (*decl_p)
1274 && !(flags & ATTR_FLAG_TYPE_IN_PLACE))
1275 {
1276 if (!dependent_type_p (*decl_p))
1277 *decl_p = cp_build_type_attribute_variant (*decl_p, late_attrs);
1278 else
1279 {
1280 *decl_p = build_variant_type_copy (*decl_p);
1281 TYPE_ATTRIBUTES (*decl_p) = late_attrs;
1282 }
1283 }
1284 else
1285 *q = late_attrs;
1286
1287 if (!DECL_P (*decl_p) && *decl_p == TYPE_MAIN_VARIANT (*decl_p))
1288 {
1289 /* We've added new attributes directly to the main variant, so
1290 now we need to update all of the other variants to include
1291 these new attributes. */
1292 tree variant;
1293 for (variant = TYPE_NEXT_VARIANT (*decl_p); variant;
1294 variant = TYPE_NEXT_VARIANT (variant))
1295 {
1296 gcc_assert (TYPE_ATTRIBUTES (variant) == old_attrs);
1297 TYPE_ATTRIBUTES (variant) = TYPE_ATTRIBUTES (*decl_p);
1298 }
1299 }
1300 }
1301
1302 /* True if ATTRS contains any dependent attributes that affect type
1303 identity. */
1304
1305 bool
any_dependent_type_attributes_p(tree attrs)1306 any_dependent_type_attributes_p (tree attrs)
1307 {
1308 for (tree a = attrs; a; a = TREE_CHAIN (a))
1309 if (ATTR_IS_DEPENDENT (a))
1310 {
1311 const attribute_spec *as = lookup_attribute_spec (TREE_PURPOSE (a));
1312 if (as && as->affects_type_identity)
1313 return true;
1314 }
1315 return false;
1316 }
1317
1318 /* Return true iff ATTRS are acceptable attributes to be applied in-place
1319 to a typedef which gives a previously unnamed class or enum a name for
1320 linkage purposes. */
1321
1322 bool
attributes_naming_typedef_ok(tree attrs)1323 attributes_naming_typedef_ok (tree attrs)
1324 {
1325 for (; attrs; attrs = TREE_CHAIN (attrs))
1326 {
1327 tree name = get_attribute_name (attrs);
1328 if (is_attribute_p ("vector_size", name))
1329 return false;
1330 }
1331 return true;
1332 }
1333
1334 /* Like reconstruct_complex_type, but handle also template trees. */
1335
1336 tree
cp_reconstruct_complex_type(tree type,tree bottom)1337 cp_reconstruct_complex_type (tree type, tree bottom)
1338 {
1339 tree inner, outer;
1340 bool late_return_type_p = false;
1341
1342 if (TYPE_PTR_P (type))
1343 {
1344 inner = cp_reconstruct_complex_type (TREE_TYPE (type), bottom);
1345 outer = build_pointer_type_for_mode (inner, TYPE_MODE (type),
1346 TYPE_REF_CAN_ALIAS_ALL (type));
1347 }
1348 else if (TREE_CODE (type) == REFERENCE_TYPE)
1349 {
1350 inner = cp_reconstruct_complex_type (TREE_TYPE (type), bottom);
1351 outer = build_reference_type_for_mode (inner, TYPE_MODE (type),
1352 TYPE_REF_CAN_ALIAS_ALL (type));
1353 }
1354 else if (TREE_CODE (type) == ARRAY_TYPE)
1355 {
1356 inner = cp_reconstruct_complex_type (TREE_TYPE (type), bottom);
1357 outer = build_cplus_array_type (inner, TYPE_DOMAIN (type));
1358 /* Don't call cp_build_qualified_type on ARRAY_TYPEs, the
1359 element type qualification will be handled by the recursive
1360 cp_reconstruct_complex_type call and cp_build_qualified_type
1361 for ARRAY_TYPEs changes the element type. */
1362 return outer;
1363 }
1364 else if (TREE_CODE (type) == FUNCTION_TYPE)
1365 {
1366 late_return_type_p = TYPE_HAS_LATE_RETURN_TYPE (type);
1367 inner = cp_reconstruct_complex_type (TREE_TYPE (type), bottom);
1368 outer = build_function_type (inner, TYPE_ARG_TYPES (type));
1369 outer = apply_memfn_quals (outer,
1370 type_memfn_quals (type),
1371 type_memfn_rqual (type));
1372 }
1373 else if (TREE_CODE (type) == METHOD_TYPE)
1374 {
1375 late_return_type_p = TYPE_HAS_LATE_RETURN_TYPE (type);
1376 inner = cp_reconstruct_complex_type (TREE_TYPE (type), bottom);
1377 /* The build_method_type_directly() routine prepends 'this' to argument list,
1378 so we must compensate by getting rid of it. */
1379 outer
1380 = build_method_type_directly
1381 (class_of_this_parm (type), inner,
1382 TREE_CHAIN (TYPE_ARG_TYPES (type)));
1383 }
1384 else if (TREE_CODE (type) == OFFSET_TYPE)
1385 {
1386 inner = cp_reconstruct_complex_type (TREE_TYPE (type), bottom);
1387 outer = build_offset_type (TYPE_OFFSET_BASETYPE (type), inner);
1388 }
1389 else
1390 return bottom;
1391
1392 if (TYPE_ATTRIBUTES (type))
1393 outer = cp_build_type_attribute_variant (outer, TYPE_ATTRIBUTES (type));
1394 outer = cp_build_qualified_type (outer, cp_type_quals (type));
1395
1396 if (late_return_type_p)
1397 TYPE_HAS_LATE_RETURN_TYPE (outer) = 1;
1398
1399 return outer;
1400 }
1401
1402 /* Replaces any constexpr expression that may be into the attributes
1403 arguments with their reduced value. */
1404
1405 static void
cp_check_const_attributes(tree attributes)1406 cp_check_const_attributes (tree attributes)
1407 {
1408 if (attributes == error_mark_node)
1409 return;
1410
1411 tree attr;
1412 for (attr = attributes; attr; attr = TREE_CHAIN (attr))
1413 {
1414 tree arg;
1415 for (arg = TREE_VALUE (attr); arg; arg = TREE_CHAIN (arg))
1416 {
1417 tree expr = TREE_VALUE (arg);
1418 if (EXPR_P (expr))
1419 TREE_VALUE (arg) = fold_non_dependent_expr (expr);
1420 }
1421 }
1422 }
1423
1424 /* Return true if TYPE is an OpenMP mappable type. */
1425 bool
cp_omp_mappable_type(tree type)1426 cp_omp_mappable_type (tree type)
1427 {
1428 /* Mappable type has to be complete. */
1429 if (type == error_mark_node || !COMPLETE_TYPE_P (type))
1430 return false;
1431 /* Arrays have mappable type if the elements have mappable type. */
1432 while (TREE_CODE (type) == ARRAY_TYPE)
1433 type = TREE_TYPE (type);
1434 /* A mappable type cannot contain virtual members. */
1435 if (CLASS_TYPE_P (type) && CLASSTYPE_VTABLES (type))
1436 return false;
1437 /* All data members must be non-static. */
1438 if (CLASS_TYPE_P (type))
1439 {
1440 tree field;
1441 for (field = TYPE_FIELDS (type); field; field = DECL_CHAIN (field))
1442 if (VAR_P (field))
1443 return false;
1444 /* All fields must have mappable types. */
1445 else if (TREE_CODE (field) == FIELD_DECL
1446 && !cp_omp_mappable_type (TREE_TYPE (field)))
1447 return false;
1448 }
1449 return true;
1450 }
1451
1452 /* Return the last pushed declaration for the symbol DECL or NULL
1453 when no such declaration exists. */
1454
1455 static tree
find_last_decl(tree decl)1456 find_last_decl (tree decl)
1457 {
1458 tree last_decl = NULL_TREE;
1459
1460 if (tree name = DECL_P (decl) ? DECL_NAME (decl) : NULL_TREE)
1461 {
1462 /* Look up the declaration in its scope. */
1463 tree pushed_scope = NULL_TREE;
1464 if (tree ctype = DECL_CONTEXT (decl))
1465 pushed_scope = push_scope (ctype);
1466
1467 last_decl = lookup_name (name);
1468
1469 if (pushed_scope)
1470 pop_scope (pushed_scope);
1471
1472 /* The declaration may be a member conversion operator
1473 or a bunch of overfloads (handle the latter below). */
1474 if (last_decl && BASELINK_P (last_decl))
1475 last_decl = BASELINK_FUNCTIONS (last_decl);
1476 }
1477
1478 if (!last_decl)
1479 return NULL_TREE;
1480
1481 if (DECL_P (last_decl) || TREE_CODE (last_decl) == OVERLOAD)
1482 {
1483 /* A set of overloads of the same function. */
1484 for (lkp_iterator iter (last_decl); iter; ++iter)
1485 {
1486 if (TREE_CODE (*iter) == OVERLOAD)
1487 continue;
1488
1489 if (decls_match (decl, *iter, /*record_decls=*/false))
1490 return *iter;
1491 }
1492 return NULL_TREE;
1493 }
1494
1495 return NULL_TREE;
1496 }
1497
1498 /* Like decl_attributes, but handle C++ complexity. */
1499
1500 void
cplus_decl_attributes(tree * decl,tree attributes,int flags)1501 cplus_decl_attributes (tree *decl, tree attributes, int flags)
1502 {
1503 if (*decl == NULL_TREE || *decl == void_type_node
1504 || *decl == error_mark_node)
1505 return;
1506
1507 /* Add implicit "omp declare target" attribute if requested. */
1508 if (scope_chain->omp_declare_target_attribute
1509 && ((VAR_P (*decl)
1510 && (TREE_STATIC (*decl) || DECL_EXTERNAL (*decl)))
1511 || TREE_CODE (*decl) == FUNCTION_DECL))
1512 {
1513 if (VAR_P (*decl)
1514 && DECL_CLASS_SCOPE_P (*decl))
1515 error ("%q+D static data member inside of declare target directive",
1516 *decl);
1517 else if (VAR_P (*decl)
1518 && (processing_template_decl
1519 || !cp_omp_mappable_type (TREE_TYPE (*decl))))
1520 attributes = tree_cons (get_identifier ("omp declare target implicit"),
1521 NULL_TREE, attributes);
1522 else
1523 attributes = tree_cons (get_identifier ("omp declare target"),
1524 NULL_TREE, attributes);
1525 }
1526
1527 if (processing_template_decl)
1528 {
1529 if (check_for_bare_parameter_packs (attributes))
1530 return;
1531
1532 save_template_attributes (&attributes, decl, flags);
1533 }
1534
1535 cp_check_const_attributes (attributes);
1536
1537 if (TREE_CODE (*decl) == TEMPLATE_DECL)
1538 decl = &DECL_TEMPLATE_RESULT (*decl);
1539
1540 if (TREE_TYPE (*decl) && TYPE_PTRMEMFUNC_P (TREE_TYPE (*decl)))
1541 {
1542 attributes
1543 = decl_attributes (decl, attributes, flags | ATTR_FLAG_FUNCTION_NEXT);
1544 decl_attributes (&TYPE_PTRMEMFUNC_FN_TYPE_RAW (TREE_TYPE (*decl)),
1545 attributes, flags);
1546 }
1547 else
1548 {
1549 tree last_decl = find_last_decl (*decl);
1550 decl_attributes (decl, attributes, flags, last_decl);
1551 }
1552
1553 if (TREE_CODE (*decl) == TYPE_DECL)
1554 SET_IDENTIFIER_TYPE_VALUE (DECL_NAME (*decl), TREE_TYPE (*decl));
1555
1556 /* Propagate deprecation out to the template. */
1557 if (TREE_DEPRECATED (*decl))
1558 if (tree ti = get_template_info (*decl))
1559 {
1560 tree tmpl = TI_TEMPLATE (ti);
1561 tree pattern = (TYPE_P (*decl) ? TREE_TYPE (tmpl)
1562 : DECL_TEMPLATE_RESULT (tmpl));
1563 if (*decl == pattern)
1564 TREE_DEPRECATED (tmpl) = true;
1565 }
1566 }
1567
1568 /* Walks through the namespace- or function-scope anonymous union
1569 OBJECT, with the indicated TYPE, building appropriate VAR_DECLs.
1570 Returns one of the fields for use in the mangled name. */
1571
1572 static tree
build_anon_union_vars(tree type,tree object)1573 build_anon_union_vars (tree type, tree object)
1574 {
1575 tree main_decl = NULL_TREE;
1576 tree field;
1577
1578 /* Rather than write the code to handle the non-union case,
1579 just give an error. */
1580 if (TREE_CODE (type) != UNION_TYPE)
1581 {
1582 error ("anonymous struct not inside named type");
1583 return error_mark_node;
1584 }
1585
1586 for (field = TYPE_FIELDS (type);
1587 field != NULL_TREE;
1588 field = DECL_CHAIN (field))
1589 {
1590 tree decl;
1591 tree ref;
1592
1593 if (DECL_ARTIFICIAL (field))
1594 continue;
1595 if (TREE_CODE (field) != FIELD_DECL)
1596 {
1597 permerror (DECL_SOURCE_LOCATION (field),
1598 "%q#D invalid; an anonymous union can only "
1599 "have non-static data members", field);
1600 continue;
1601 }
1602
1603 if (TREE_PRIVATE (field))
1604 permerror (DECL_SOURCE_LOCATION (field),
1605 "private member %q#D in anonymous union", field);
1606 else if (TREE_PROTECTED (field))
1607 permerror (DECL_SOURCE_LOCATION (field),
1608 "protected member %q#D in anonymous union", field);
1609
1610 if (processing_template_decl)
1611 ref = build_min_nt_loc (UNKNOWN_LOCATION, COMPONENT_REF, object,
1612 DECL_NAME (field), NULL_TREE);
1613 else
1614 ref = build_class_member_access_expr (object, field, NULL_TREE,
1615 false, tf_warning_or_error);
1616
1617 if (DECL_NAME (field))
1618 {
1619 tree base;
1620
1621 decl = build_decl (input_location,
1622 VAR_DECL, DECL_NAME (field), TREE_TYPE (field));
1623 DECL_ANON_UNION_VAR_P (decl) = 1;
1624 DECL_ARTIFICIAL (decl) = 1;
1625
1626 base = get_base_address (object);
1627 TREE_PUBLIC (decl) = TREE_PUBLIC (base);
1628 TREE_STATIC (decl) = TREE_STATIC (base);
1629 DECL_EXTERNAL (decl) = DECL_EXTERNAL (base);
1630
1631 SET_DECL_VALUE_EXPR (decl, ref);
1632 DECL_HAS_VALUE_EXPR_P (decl) = 1;
1633
1634 decl = pushdecl (decl);
1635 }
1636 else if (ANON_AGGR_TYPE_P (TREE_TYPE (field)))
1637 decl = build_anon_union_vars (TREE_TYPE (field), ref);
1638 else
1639 decl = 0;
1640
1641 if (main_decl == NULL_TREE)
1642 main_decl = decl;
1643 }
1644
1645 return main_decl;
1646 }
1647
1648 /* Finish off the processing of a UNION_TYPE structure. If the union is an
1649 anonymous union, then all members must be laid out together. PUBLIC_P
1650 is nonzero if this union is not declared static. */
1651
1652 void
finish_anon_union(tree anon_union_decl)1653 finish_anon_union (tree anon_union_decl)
1654 {
1655 tree type;
1656 tree main_decl;
1657 bool public_p;
1658
1659 if (anon_union_decl == error_mark_node)
1660 return;
1661
1662 type = TREE_TYPE (anon_union_decl);
1663 public_p = TREE_PUBLIC (anon_union_decl);
1664
1665 /* The VAR_DECL's context is the same as the TYPE's context. */
1666 DECL_CONTEXT (anon_union_decl) = DECL_CONTEXT (TYPE_NAME (type));
1667
1668 if (TYPE_FIELDS (type) == NULL_TREE)
1669 return;
1670
1671 if (public_p)
1672 {
1673 error ("namespace-scope anonymous aggregates must be static");
1674 return;
1675 }
1676
1677 main_decl = build_anon_union_vars (type, anon_union_decl);
1678 if (main_decl == error_mark_node)
1679 return;
1680 if (main_decl == NULL_TREE)
1681 {
1682 pedwarn (input_location, 0, "anonymous union with no members");
1683 return;
1684 }
1685
1686 if (!processing_template_decl)
1687 {
1688 /* Use main_decl to set the mangled name. */
1689 DECL_NAME (anon_union_decl) = DECL_NAME (main_decl);
1690 maybe_commonize_var (anon_union_decl);
1691 if (TREE_STATIC (anon_union_decl) || DECL_EXTERNAL (anon_union_decl))
1692 mangle_decl (anon_union_decl);
1693 DECL_NAME (anon_union_decl) = NULL_TREE;
1694 }
1695
1696 pushdecl (anon_union_decl);
1697 cp_finish_decl (anon_union_decl, NULL_TREE, false, NULL_TREE, 0);
1698 }
1699
1700 /* Auxiliary functions to make type signatures for
1701 `operator new' and `operator delete' correspond to
1702 what compiler will be expecting. */
1703
1704 tree
coerce_new_type(tree type)1705 coerce_new_type (tree type)
1706 {
1707 int e = 0;
1708 tree args = TYPE_ARG_TYPES (type);
1709
1710 gcc_assert (TREE_CODE (type) == FUNCTION_TYPE);
1711
1712 if (!same_type_p (TREE_TYPE (type), ptr_type_node))
1713 {
1714 e = 1;
1715 error ("%<operator new%> must return type %qT", ptr_type_node);
1716 }
1717
1718 if (args && args != void_list_node)
1719 {
1720 if (TREE_PURPOSE (args))
1721 {
1722 /* [basic.stc.dynamic.allocation]
1723
1724 The first parameter shall not have an associated default
1725 argument. */
1726 error ("the first parameter of %<operator new%> cannot "
1727 "have a default argument");
1728 /* Throw away the default argument. */
1729 TREE_PURPOSE (args) = NULL_TREE;
1730 }
1731
1732 if (!same_type_p (TREE_VALUE (args), size_type_node))
1733 {
1734 e = 2;
1735 args = TREE_CHAIN (args);
1736 }
1737 }
1738 else
1739 e = 2;
1740
1741 if (e == 2)
1742 permerror (input_location, "%<operator new%> takes type %<size_t%> (%qT) "
1743 "as first parameter", size_type_node);
1744
1745 switch (e)
1746 {
1747 case 2:
1748 args = tree_cons (NULL_TREE, size_type_node, args);
1749 /* Fall through. */
1750 case 1:
1751 type = build_exception_variant
1752 (build_function_type (ptr_type_node, args),
1753 TYPE_RAISES_EXCEPTIONS (type));
1754 /* Fall through. */
1755 default:;
1756 }
1757 return type;
1758 }
1759
1760 tree
coerce_delete_type(tree type)1761 coerce_delete_type (tree type)
1762 {
1763 int e = 0;
1764 tree args = TYPE_ARG_TYPES (type);
1765
1766 gcc_assert (TREE_CODE (type) == FUNCTION_TYPE);
1767
1768 if (!same_type_p (TREE_TYPE (type), void_type_node))
1769 {
1770 e = 1;
1771 error ("%<operator delete%> must return type %qT", void_type_node);
1772 }
1773
1774 if (!args || args == void_list_node
1775 || !same_type_p (TREE_VALUE (args), ptr_type_node))
1776 {
1777 e = 2;
1778 if (args && args != void_list_node)
1779 args = TREE_CHAIN (args);
1780 error ("%<operator delete%> takes type %qT as first parameter",
1781 ptr_type_node);
1782 }
1783 switch (e)
1784 {
1785 case 2:
1786 args = tree_cons (NULL_TREE, ptr_type_node, args);
1787 /* Fall through. */
1788 case 1:
1789 type = build_exception_variant
1790 (build_function_type (void_type_node, args),
1791 TYPE_RAISES_EXCEPTIONS (type));
1792 /* Fall through. */
1793 default:;
1794 }
1795
1796 return type;
1797 }
1798
1799 /* DECL is a VAR_DECL for a vtable: walk through the entries in the vtable
1800 and mark them as needed. */
1801
1802 static void
mark_vtable_entries(tree decl)1803 mark_vtable_entries (tree decl)
1804 {
1805 tree fnaddr;
1806 unsigned HOST_WIDE_INT idx;
1807
1808 /* It's OK for the vtable to refer to deprecated virtual functions. */
1809 warning_sentinel w(warn_deprecated_decl);
1810
1811 FOR_EACH_CONSTRUCTOR_VALUE (CONSTRUCTOR_ELTS (DECL_INITIAL (decl)),
1812 idx, fnaddr)
1813 {
1814 tree fn;
1815
1816 STRIP_NOPS (fnaddr);
1817
1818 if (TREE_CODE (fnaddr) != ADDR_EXPR
1819 && TREE_CODE (fnaddr) != FDESC_EXPR)
1820 /* This entry is an offset: a virtual base class offset, a
1821 virtual call offset, an RTTI offset, etc. */
1822 continue;
1823
1824 fn = TREE_OPERAND (fnaddr, 0);
1825 TREE_ADDRESSABLE (fn) = 1;
1826 /* When we don't have vcall offsets, we output thunks whenever
1827 we output the vtables that contain them. With vcall offsets,
1828 we know all the thunks we'll need when we emit a virtual
1829 function, so we emit the thunks there instead. */
1830 if (DECL_THUNK_P (fn))
1831 use_thunk (fn, /*emit_p=*/0);
1832 /* Set the location, as marking the function could cause
1833 instantiation. We do not need to preserve the incoming
1834 location, as we're called from c_parse_final_cleanups, which
1835 takes care of that. */
1836 input_location = DECL_SOURCE_LOCATION (fn);
1837 mark_used (fn);
1838 }
1839 }
1840
1841 /* Set DECL up to have the closest approximation of "initialized common"
1842 linkage available. */
1843
1844 void
comdat_linkage(tree decl)1845 comdat_linkage (tree decl)
1846 {
1847 if (flag_weak)
1848 make_decl_one_only (decl, cxx_comdat_group (decl));
1849 else if (TREE_CODE (decl) == FUNCTION_DECL
1850 || (VAR_P (decl) && DECL_ARTIFICIAL (decl)))
1851 /* We can just emit function and compiler-generated variables
1852 statically; having multiple copies is (for the most part) only
1853 a waste of space.
1854
1855 There are two correctness issues, however: the address of a
1856 template instantiation with external linkage should be the
1857 same, independent of what translation unit asks for the
1858 address, and this will not hold when we emit multiple copies of
1859 the function. However, there's little else we can do.
1860
1861 Also, by default, the typeinfo implementation assumes that
1862 there will be only one copy of the string used as the name for
1863 each type. Therefore, if weak symbols are unavailable, the
1864 run-time library should perform a more conservative check; it
1865 should perform a string comparison, rather than an address
1866 comparison. */
1867 TREE_PUBLIC (decl) = 0;
1868 else
1869 {
1870 /* Static data member template instantiations, however, cannot
1871 have multiple copies. */
1872 if (DECL_INITIAL (decl) == 0
1873 || DECL_INITIAL (decl) == error_mark_node)
1874 DECL_COMMON (decl) = 1;
1875 else if (EMPTY_CONSTRUCTOR_P (DECL_INITIAL (decl)))
1876 {
1877 DECL_COMMON (decl) = 1;
1878 DECL_INITIAL (decl) = error_mark_node;
1879 }
1880 else if (!DECL_EXPLICIT_INSTANTIATION (decl))
1881 {
1882 /* We can't do anything useful; leave vars for explicit
1883 instantiation. */
1884 DECL_EXTERNAL (decl) = 1;
1885 DECL_NOT_REALLY_EXTERN (decl) = 0;
1886 }
1887 }
1888
1889 if (TREE_PUBLIC (decl))
1890 DECL_COMDAT (decl) = 1;
1891 }
1892
1893 /* For win32 we also want to put explicit instantiations in
1894 linkonce sections, so that they will be merged with implicit
1895 instantiations; otherwise we get duplicate symbol errors.
1896 For Darwin we do not want explicit instantiations to be
1897 linkonce. */
1898
1899 void
maybe_make_one_only(tree decl)1900 maybe_make_one_only (tree decl)
1901 {
1902 /* We used to say that this was not necessary on targets that support weak
1903 symbols, because the implicit instantiations will defer to the explicit
1904 one. However, that's not actually the case in SVR4; a strong definition
1905 after a weak one is an error. Also, not making explicit
1906 instantiations one_only means that we can end up with two copies of
1907 some template instantiations. */
1908 if (! flag_weak)
1909 return;
1910
1911 /* We can't set DECL_COMDAT on functions, or cp_finish_file will think
1912 we can get away with not emitting them if they aren't used. We need
1913 to for variables so that cp_finish_decl will update their linkage,
1914 because their DECL_INITIAL may not have been set properly yet. */
1915
1916 if (!TARGET_WEAK_NOT_IN_ARCHIVE_TOC
1917 || (! DECL_EXPLICIT_INSTANTIATION (decl)
1918 && ! DECL_TEMPLATE_SPECIALIZATION (decl)))
1919 {
1920 make_decl_one_only (decl, cxx_comdat_group (decl));
1921
1922 if (VAR_P (decl))
1923 {
1924 varpool_node *node = varpool_node::get_create (decl);
1925 DECL_COMDAT (decl) = 1;
1926 /* Mark it needed so we don't forget to emit it. */
1927 node->forced_by_abi = true;
1928 TREE_USED (decl) = 1;
1929 }
1930 }
1931 }
1932
1933 /* Returns true iff DECL, a FUNCTION_DECL or VAR_DECL, has vague linkage.
1934 This predicate will give the right answer during parsing of the
1935 function, which other tests may not. */
1936
1937 bool
vague_linkage_p(tree decl)1938 vague_linkage_p (tree decl)
1939 {
1940 if (!TREE_PUBLIC (decl))
1941 {
1942 /* maybe_thunk_body clears TREE_PUBLIC and DECL_ABSTRACT_P on the
1943 maybe-in-charge 'tor variants; in that case we need to check one of
1944 the "clones" for the real linkage. But only in that case; before
1945 maybe_clone_body we haven't yet copied the linkage to the clones. */
1946 if ((DECL_MAYBE_IN_CHARGE_DESTRUCTOR_P (decl)
1947 || DECL_MAYBE_IN_CHARGE_CONSTRUCTOR_P (decl))
1948 && !DECL_ABSTRACT_P (decl)
1949 && DECL_CHAIN (decl)
1950 && DECL_CLONED_FUNCTION_P (DECL_CHAIN (decl)))
1951 return vague_linkage_p (DECL_CHAIN (decl));
1952
1953 gcc_checking_assert (!DECL_COMDAT (decl));
1954 return false;
1955 }
1956 /* Unfortunately, import_export_decl has not always been called
1957 before the function is processed, so we cannot simply check
1958 DECL_COMDAT. */
1959 if (DECL_COMDAT (decl)
1960 || (TREE_CODE (decl) == FUNCTION_DECL
1961 && DECL_DECLARED_INLINE_P (decl))
1962 || (DECL_LANG_SPECIFIC (decl)
1963 && DECL_TEMPLATE_INSTANTIATION (decl))
1964 || (VAR_P (decl) && DECL_INLINE_VAR_P (decl)))
1965 return true;
1966 else if (DECL_FUNCTION_SCOPE_P (decl))
1967 /* A local static in an inline effectively has vague linkage. */
1968 return (TREE_STATIC (decl)
1969 && vague_linkage_p (DECL_CONTEXT (decl)));
1970 else
1971 return false;
1972 }
1973
1974 /* Determine whether or not we want to specifically import or export CTYPE,
1975 using various heuristics. */
1976
1977 static void
import_export_class(tree ctype)1978 import_export_class (tree ctype)
1979 {
1980 /* -1 for imported, 1 for exported. */
1981 int import_export = 0;
1982
1983 /* It only makes sense to call this function at EOF. The reason is
1984 that this function looks at whether or not the first non-inline
1985 non-abstract virtual member function has been defined in this
1986 translation unit. But, we can't possibly know that until we've
1987 seen the entire translation unit. */
1988 gcc_assert (at_eof);
1989
1990 if (CLASSTYPE_INTERFACE_KNOWN (ctype))
1991 return;
1992
1993 /* If MULTIPLE_SYMBOL_SPACES is set and we saw a #pragma interface,
1994 we will have CLASSTYPE_INTERFACE_ONLY set but not
1995 CLASSTYPE_INTERFACE_KNOWN. In that case, we don't want to use this
1996 heuristic because someone will supply a #pragma implementation
1997 elsewhere, and deducing it here would produce a conflict. */
1998 if (CLASSTYPE_INTERFACE_ONLY (ctype))
1999 return;
2000
2001 if (lookup_attribute ("dllimport", TYPE_ATTRIBUTES (ctype)))
2002 import_export = -1;
2003 else if (lookup_attribute ("dllexport", TYPE_ATTRIBUTES (ctype)))
2004 import_export = 1;
2005 else if (CLASSTYPE_IMPLICIT_INSTANTIATION (ctype)
2006 && !flag_implicit_templates)
2007 /* For a template class, without -fimplicit-templates, check the
2008 repository. If the virtual table is assigned to this
2009 translation unit, then export the class; otherwise, import
2010 it. */
2011 import_export = repo_export_class_p (ctype) ? 1 : -1;
2012 else if (TYPE_POLYMORPHIC_P (ctype))
2013 {
2014 /* The ABI specifies that the virtual table and associated
2015 information are emitted with the key method, if any. */
2016 tree method = CLASSTYPE_KEY_METHOD (ctype);
2017 /* If weak symbol support is not available, then we must be
2018 careful not to emit the vtable when the key function is
2019 inline. An inline function can be defined in multiple
2020 translation units. If we were to emit the vtable in each
2021 translation unit containing a definition, we would get
2022 multiple definition errors at link-time. */
2023 if (method && (flag_weak || ! DECL_DECLARED_INLINE_P (method)))
2024 import_export = (DECL_REALLY_EXTERN (method) ? -1 : 1);
2025 }
2026
2027 /* When MULTIPLE_SYMBOL_SPACES is set, we cannot count on seeing
2028 a definition anywhere else. */
2029 if (MULTIPLE_SYMBOL_SPACES && import_export == -1)
2030 import_export = 0;
2031
2032 /* Allow back ends the chance to overrule the decision. */
2033 if (targetm.cxx.import_export_class)
2034 import_export = targetm.cxx.import_export_class (ctype, import_export);
2035
2036 if (import_export)
2037 {
2038 SET_CLASSTYPE_INTERFACE_KNOWN (ctype);
2039 CLASSTYPE_INTERFACE_ONLY (ctype) = (import_export < 0);
2040 }
2041 }
2042
2043 /* Return true if VAR has already been provided to the back end; in that
2044 case VAR should not be modified further by the front end. */
2045 static bool
var_finalized_p(tree var)2046 var_finalized_p (tree var)
2047 {
2048 return varpool_node::get_create (var)->definition;
2049 }
2050
2051 /* DECL is a VAR_DECL or FUNCTION_DECL which, for whatever reason,
2052 must be emitted in this translation unit. Mark it as such. */
2053
2054 void
mark_needed(tree decl)2055 mark_needed (tree decl)
2056 {
2057 TREE_USED (decl) = 1;
2058 if (TREE_CODE (decl) == FUNCTION_DECL)
2059 {
2060 /* Extern inline functions don't become needed when referenced.
2061 If we know a method will be emitted in other TU and no new
2062 functions can be marked reachable, just use the external
2063 definition. */
2064 struct cgraph_node *node = cgraph_node::get_create (decl);
2065 node->forced_by_abi = true;
2066
2067 /* #pragma interface and -frepo code can call mark_needed for
2068 maybe-in-charge 'tors; mark the clones as well. */
2069 tree clone;
2070 FOR_EACH_CLONE (clone, decl)
2071 mark_needed (clone);
2072 }
2073 else if (VAR_P (decl))
2074 {
2075 varpool_node *node = varpool_node::get_create (decl);
2076 /* C++ frontend use mark_decl_references to force COMDAT variables
2077 to be output that might appear dead otherwise. */
2078 node->forced_by_abi = true;
2079 }
2080 }
2081
2082 /* DECL is either a FUNCTION_DECL or a VAR_DECL. This function
2083 returns true if a definition of this entity should be provided in
2084 this object file. Callers use this function to determine whether
2085 or not to let the back end know that a definition of DECL is
2086 available in this translation unit. */
2087
2088 bool
decl_needed_p(tree decl)2089 decl_needed_p (tree decl)
2090 {
2091 gcc_assert (VAR_OR_FUNCTION_DECL_P (decl));
2092 /* This function should only be called at the end of the translation
2093 unit. We cannot be sure of whether or not something will be
2094 COMDAT until that point. */
2095 gcc_assert (at_eof);
2096
2097 /* All entities with external linkage that are not COMDAT/EXTERN should be
2098 emitted; they may be referred to from other object files. */
2099 if (TREE_PUBLIC (decl) && !DECL_COMDAT (decl) && !DECL_REALLY_EXTERN (decl))
2100 return true;
2101 /* Functions marked "dllexport" must be emitted so that they are
2102 visible to other DLLs. */
2103 if (flag_keep_inline_dllexport
2104 && lookup_attribute ("dllexport", DECL_ATTRIBUTES (decl)))
2105 return true;
2106
2107 /* When not optimizing, do not bother to produce definitions for extern
2108 symbols. */
2109 if (DECL_REALLY_EXTERN (decl)
2110 && ((TREE_CODE (decl) != FUNCTION_DECL
2111 && !optimize)
2112 || (TREE_CODE (decl) == FUNCTION_DECL
2113 && !opt_for_fn (decl, optimize)))
2114 && !lookup_attribute ("always_inline", decl))
2115 return false;
2116
2117 /* If this entity was used, let the back end see it; it will decide
2118 whether or not to emit it into the object file. */
2119 if (TREE_USED (decl))
2120 return true;
2121
2122 /* Virtual functions might be needed for devirtualization. */
2123 if (flag_devirtualize
2124 && TREE_CODE (decl) == FUNCTION_DECL
2125 && DECL_VIRTUAL_P (decl))
2126 return true;
2127
2128 /* Otherwise, DECL does not need to be emitted -- yet. A subsequent
2129 reference to DECL might cause it to be emitted later. */
2130 return false;
2131 }
2132
2133 /* If necessary, write out the vtables for the dynamic class CTYPE.
2134 Returns true if any vtables were emitted. */
2135
2136 static bool
maybe_emit_vtables(tree ctype)2137 maybe_emit_vtables (tree ctype)
2138 {
2139 tree vtbl;
2140 tree primary_vtbl;
2141 int needed = 0;
2142 varpool_node *current = NULL, *last = NULL;
2143
2144 /* If the vtables for this class have already been emitted there is
2145 nothing more to do. */
2146 primary_vtbl = CLASSTYPE_VTABLES (ctype);
2147 if (var_finalized_p (primary_vtbl))
2148 return false;
2149 /* Ignore dummy vtables made by get_vtable_decl. */
2150 if (TREE_TYPE (primary_vtbl) == void_type_node)
2151 return false;
2152
2153 /* On some targets, we cannot determine the key method until the end
2154 of the translation unit -- which is when this function is
2155 called. */
2156 if (!targetm.cxx.key_method_may_be_inline ())
2157 determine_key_method (ctype);
2158
2159 /* See if any of the vtables are needed. */
2160 for (vtbl = CLASSTYPE_VTABLES (ctype); vtbl; vtbl = DECL_CHAIN (vtbl))
2161 {
2162 import_export_decl (vtbl);
2163 if (DECL_NOT_REALLY_EXTERN (vtbl) && decl_needed_p (vtbl))
2164 needed = 1;
2165 }
2166 if (!needed)
2167 {
2168 /* If the references to this class' vtables are optimized away,
2169 still emit the appropriate debugging information. See
2170 dfs_debug_mark. */
2171 if (DECL_COMDAT (primary_vtbl)
2172 && CLASSTYPE_DEBUG_REQUESTED (ctype))
2173 note_debug_info_needed (ctype);
2174 return false;
2175 }
2176
2177 /* The ABI requires that we emit all of the vtables if we emit any
2178 of them. */
2179 for (vtbl = CLASSTYPE_VTABLES (ctype); vtbl; vtbl = DECL_CHAIN (vtbl))
2180 {
2181 /* Mark entities references from the virtual table as used. */
2182 mark_vtable_entries (vtbl);
2183
2184 if (TREE_TYPE (DECL_INITIAL (vtbl)) == 0)
2185 {
2186 vec<tree, va_gc> *cleanups = NULL;
2187 tree expr = store_init_value (vtbl, DECL_INITIAL (vtbl), &cleanups,
2188 LOOKUP_NORMAL);
2189
2190 /* It had better be all done at compile-time. */
2191 gcc_assert (!expr && !cleanups);
2192 }
2193
2194 /* Write it out. */
2195 DECL_EXTERNAL (vtbl) = 0;
2196 rest_of_decl_compilation (vtbl, 1, 1);
2197
2198 /* Because we're only doing syntax-checking, we'll never end up
2199 actually marking the variable as written. */
2200 if (flag_syntax_only)
2201 TREE_ASM_WRITTEN (vtbl) = 1;
2202 else if (DECL_ONE_ONLY (vtbl))
2203 {
2204 current = varpool_node::get_create (vtbl);
2205 if (last)
2206 current->add_to_same_comdat_group (last);
2207 last = current;
2208 }
2209 }
2210
2211 /* Since we're writing out the vtable here, also write the debug
2212 info. */
2213 note_debug_info_needed (ctype);
2214
2215 return true;
2216 }
2217
2218 /* A special return value from type_visibility meaning internal
2219 linkage. */
2220
2221 enum { VISIBILITY_ANON = VISIBILITY_INTERNAL+1 };
2222
2223 /* walk_tree helper function for type_visibility. */
2224
2225 static tree
min_vis_r(tree * tp,int * walk_subtrees,void * data)2226 min_vis_r (tree *tp, int *walk_subtrees, void *data)
2227 {
2228 int *vis_p = (int *)data;
2229 if (! TYPE_P (*tp))
2230 {
2231 *walk_subtrees = 0;
2232 }
2233 else if (OVERLOAD_TYPE_P (*tp)
2234 && !TREE_PUBLIC (TYPE_MAIN_DECL (*tp)))
2235 {
2236 *vis_p = VISIBILITY_ANON;
2237 return *tp;
2238 }
2239 else if (CLASS_TYPE_P (*tp)
2240 && CLASSTYPE_VISIBILITY (*tp) > *vis_p)
2241 *vis_p = CLASSTYPE_VISIBILITY (*tp);
2242 return NULL;
2243 }
2244
2245 /* Returns the visibility of TYPE, which is the minimum visibility of its
2246 component types. */
2247
2248 static int
type_visibility(tree type)2249 type_visibility (tree type)
2250 {
2251 int vis = VISIBILITY_DEFAULT;
2252 cp_walk_tree_without_duplicates (&type, min_vis_r, &vis);
2253 return vis;
2254 }
2255
2256 /* Limit the visibility of DECL to VISIBILITY, if not explicitly
2257 specified (or if VISIBILITY is static). If TMPL is true, this
2258 constraint is for a template argument, and takes precedence
2259 over explicitly-specified visibility on the template. */
2260
2261 static void
constrain_visibility(tree decl,int visibility,bool tmpl)2262 constrain_visibility (tree decl, int visibility, bool tmpl)
2263 {
2264 if (visibility == VISIBILITY_ANON)
2265 {
2266 /* extern "C" declarations aren't affected by the anonymous
2267 namespace. */
2268 if (!DECL_EXTERN_C_P (decl))
2269 {
2270 TREE_PUBLIC (decl) = 0;
2271 DECL_WEAK (decl) = 0;
2272 DECL_COMMON (decl) = 0;
2273 DECL_COMDAT (decl) = false;
2274 if (VAR_OR_FUNCTION_DECL_P (decl))
2275 {
2276 struct symtab_node *snode = symtab_node::get (decl);
2277
2278 if (snode)
2279 snode->set_comdat_group (NULL);
2280 }
2281 DECL_INTERFACE_KNOWN (decl) = 1;
2282 if (DECL_LANG_SPECIFIC (decl))
2283 DECL_NOT_REALLY_EXTERN (decl) = 1;
2284 }
2285 }
2286 else if (visibility > DECL_VISIBILITY (decl)
2287 && (tmpl || !DECL_VISIBILITY_SPECIFIED (decl)))
2288 {
2289 DECL_VISIBILITY (decl) = (enum symbol_visibility) visibility;
2290 /* This visibility was not specified. */
2291 DECL_VISIBILITY_SPECIFIED (decl) = false;
2292 }
2293 }
2294
2295 /* Constrain the visibility of DECL based on the visibility of its template
2296 arguments. */
2297
2298 static void
constrain_visibility_for_template(tree decl,tree targs)2299 constrain_visibility_for_template (tree decl, tree targs)
2300 {
2301 /* If this is a template instantiation, check the innermost
2302 template args for visibility constraints. The outer template
2303 args are covered by the class check. */
2304 tree args = INNERMOST_TEMPLATE_ARGS (targs);
2305 int i;
2306 for (i = TREE_VEC_LENGTH (args); i > 0; --i)
2307 {
2308 int vis = 0;
2309
2310 tree arg = TREE_VEC_ELT (args, i-1);
2311 if (TYPE_P (arg))
2312 vis = type_visibility (arg);
2313 else
2314 {
2315 if (REFERENCE_REF_P (arg))
2316 arg = TREE_OPERAND (arg, 0);
2317 if (TREE_TYPE (arg))
2318 STRIP_NOPS (arg);
2319 if (TREE_CODE (arg) == ADDR_EXPR)
2320 arg = TREE_OPERAND (arg, 0);
2321 if (VAR_OR_FUNCTION_DECL_P (arg))
2322 {
2323 if (! TREE_PUBLIC (arg))
2324 vis = VISIBILITY_ANON;
2325 else
2326 vis = DECL_VISIBILITY (arg);
2327 }
2328 }
2329 if (vis)
2330 constrain_visibility (decl, vis, true);
2331 }
2332 }
2333
2334 /* Like c_determine_visibility, but with additional C++-specific
2335 behavior.
2336
2337 Function-scope entities can rely on the function's visibility because
2338 it is set in start_preparsed_function.
2339
2340 Class-scope entities cannot rely on the class's visibility until the end
2341 of the enclosing class definition.
2342
2343 Note that because namespaces have multiple independent definitions,
2344 namespace visibility is handled elsewhere using the #pragma visibility
2345 machinery rather than by decorating the namespace declaration.
2346
2347 The goal is for constraints from the type to give a diagnostic, and
2348 other constraints to be applied silently. */
2349
2350 void
determine_visibility(tree decl)2351 determine_visibility (tree decl)
2352 {
2353 /* Remember that all decls get VISIBILITY_DEFAULT when built. */
2354
2355 /* Only relevant for names with external linkage. */
2356 if (!TREE_PUBLIC (decl))
2357 return;
2358
2359 /* Cloned constructors and destructors get the same visibility as
2360 the underlying function. That should be set up in
2361 maybe_clone_body. */
2362 gcc_assert (!DECL_CLONED_FUNCTION_P (decl));
2363
2364 bool orig_visibility_specified = DECL_VISIBILITY_SPECIFIED (decl);
2365 enum symbol_visibility orig_visibility = DECL_VISIBILITY (decl);
2366
2367 /* The decl may be a template instantiation, which could influence
2368 visibilty. */
2369 tree template_decl = NULL_TREE;
2370 if (TREE_CODE (decl) == TYPE_DECL)
2371 {
2372 if (CLASS_TYPE_P (TREE_TYPE (decl)))
2373 {
2374 if (CLASSTYPE_USE_TEMPLATE (TREE_TYPE (decl)))
2375 template_decl = decl;
2376 }
2377 else if (TYPE_TEMPLATE_INFO (TREE_TYPE (decl)))
2378 template_decl = decl;
2379 }
2380 else if (DECL_LANG_SPECIFIC (decl) && DECL_USE_TEMPLATE (decl))
2381 template_decl = decl;
2382
2383 /* If DECL is a member of a class, visibility specifiers on the
2384 class can influence the visibility of the DECL. */
2385 tree class_type = NULL_TREE;
2386 if (DECL_CLASS_SCOPE_P (decl))
2387 class_type = DECL_CONTEXT (decl);
2388 else
2389 {
2390 /* Not a class member. */
2391
2392 /* Virtual tables have DECL_CONTEXT set to their associated class,
2393 so they are automatically handled above. */
2394 gcc_assert (!VAR_P (decl)
2395 || !DECL_VTABLE_OR_VTT_P (decl));
2396
2397 if (DECL_FUNCTION_SCOPE_P (decl) && ! DECL_VISIBILITY_SPECIFIED (decl))
2398 {
2399 /* Local statics and classes get the visibility of their
2400 containing function by default, except that
2401 -fvisibility-inlines-hidden doesn't affect them. */
2402 tree fn = DECL_CONTEXT (decl);
2403 if (DECL_VISIBILITY_SPECIFIED (fn))
2404 {
2405 DECL_VISIBILITY (decl) = DECL_VISIBILITY (fn);
2406 DECL_VISIBILITY_SPECIFIED (decl) =
2407 DECL_VISIBILITY_SPECIFIED (fn);
2408 }
2409 else
2410 {
2411 if (DECL_CLASS_SCOPE_P (fn))
2412 determine_visibility_from_class (decl, DECL_CONTEXT (fn));
2413 else if (determine_hidden_inline (fn))
2414 {
2415 DECL_VISIBILITY (decl) = default_visibility;
2416 DECL_VISIBILITY_SPECIFIED (decl) =
2417 visibility_options.inpragma;
2418 }
2419 else
2420 {
2421 DECL_VISIBILITY (decl) = DECL_VISIBILITY (fn);
2422 DECL_VISIBILITY_SPECIFIED (decl) =
2423 DECL_VISIBILITY_SPECIFIED (fn);
2424 }
2425 }
2426
2427 /* Local classes in templates have CLASSTYPE_USE_TEMPLATE set,
2428 but have no TEMPLATE_INFO, so don't try to check it. */
2429 template_decl = NULL_TREE;
2430 }
2431 else if (VAR_P (decl) && DECL_TINFO_P (decl)
2432 && flag_visibility_ms_compat)
2433 {
2434 /* Under -fvisibility-ms-compat, types are visible by default,
2435 even though their contents aren't. */
2436 tree underlying_type = TREE_TYPE (DECL_NAME (decl));
2437 int underlying_vis = type_visibility (underlying_type);
2438 if (underlying_vis == VISIBILITY_ANON
2439 || (CLASS_TYPE_P (underlying_type)
2440 && CLASSTYPE_VISIBILITY_SPECIFIED (underlying_type)))
2441 constrain_visibility (decl, underlying_vis, false);
2442 else
2443 DECL_VISIBILITY (decl) = VISIBILITY_DEFAULT;
2444 }
2445 else if (VAR_P (decl) && DECL_TINFO_P (decl))
2446 {
2447 /* tinfo visibility is based on the type it's for. */
2448 constrain_visibility
2449 (decl, type_visibility (TREE_TYPE (DECL_NAME (decl))), false);
2450
2451 /* Give the target a chance to override the visibility associated
2452 with DECL. */
2453 if (TREE_PUBLIC (decl)
2454 && !DECL_REALLY_EXTERN (decl)
2455 && CLASS_TYPE_P (TREE_TYPE (DECL_NAME (decl)))
2456 && !CLASSTYPE_VISIBILITY_SPECIFIED (TREE_TYPE (DECL_NAME (decl))))
2457 targetm.cxx.determine_class_data_visibility (decl);
2458 }
2459 else if (template_decl)
2460 /* Template instantiations and specializations get visibility based
2461 on their template unless they override it with an attribute. */;
2462 else if (! DECL_VISIBILITY_SPECIFIED (decl))
2463 {
2464 if (determine_hidden_inline (decl))
2465 DECL_VISIBILITY (decl) = VISIBILITY_HIDDEN;
2466 else
2467 {
2468 /* Set default visibility to whatever the user supplied with
2469 #pragma GCC visibility or a namespace visibility attribute. */
2470 DECL_VISIBILITY (decl) = default_visibility;
2471 DECL_VISIBILITY_SPECIFIED (decl) = visibility_options.inpragma;
2472 }
2473 }
2474 }
2475
2476 if (template_decl)
2477 {
2478 /* If the specialization doesn't specify visibility, use the
2479 visibility from the template. */
2480 tree tinfo = get_template_info (template_decl);
2481 tree args = TI_ARGS (tinfo);
2482 tree attribs = (TREE_CODE (decl) == TYPE_DECL
2483 ? TYPE_ATTRIBUTES (TREE_TYPE (decl))
2484 : DECL_ATTRIBUTES (decl));
2485
2486 if (args != error_mark_node)
2487 {
2488 tree pattern = DECL_TEMPLATE_RESULT (TI_TEMPLATE (tinfo));
2489
2490 if (!DECL_VISIBILITY_SPECIFIED (decl))
2491 {
2492 if (!DECL_VISIBILITY_SPECIFIED (pattern)
2493 && determine_hidden_inline (decl))
2494 DECL_VISIBILITY (decl) = VISIBILITY_HIDDEN;
2495 else
2496 {
2497 DECL_VISIBILITY (decl) = DECL_VISIBILITY (pattern);
2498 DECL_VISIBILITY_SPECIFIED (decl)
2499 = DECL_VISIBILITY_SPECIFIED (pattern);
2500 }
2501 }
2502
2503 if (args
2504 /* Template argument visibility outweighs #pragma or namespace
2505 visibility, but not an explicit attribute. */
2506 && !lookup_attribute ("visibility", attribs))
2507 {
2508 int depth = TMPL_ARGS_DEPTH (args);
2509 if (DECL_VISIBILITY_SPECIFIED (decl))
2510 {
2511 /* A class template member with explicit visibility
2512 overrides the class visibility, so we need to apply
2513 all the levels of template args directly. */
2514 int i;
2515 for (i = 1; i <= depth; ++i)
2516 {
2517 tree lev = TMPL_ARGS_LEVEL (args, i);
2518 constrain_visibility_for_template (decl, lev);
2519 }
2520 }
2521 else if (PRIMARY_TEMPLATE_P (TI_TEMPLATE (tinfo)))
2522 /* Limit visibility based on its template arguments. */
2523 constrain_visibility_for_template (decl, args);
2524 }
2525 }
2526 }
2527
2528 if (class_type)
2529 determine_visibility_from_class (decl, class_type);
2530
2531 if (decl_anon_ns_mem_p (decl))
2532 /* Names in an anonymous namespace get internal linkage.
2533 This might change once we implement export. */
2534 constrain_visibility (decl, VISIBILITY_ANON, false);
2535 else if (TREE_CODE (decl) != TYPE_DECL)
2536 {
2537 /* Propagate anonymity from type to decl. */
2538 int tvis = type_visibility (TREE_TYPE (decl));
2539 if (tvis == VISIBILITY_ANON
2540 || ! DECL_VISIBILITY_SPECIFIED (decl))
2541 constrain_visibility (decl, tvis, false);
2542 }
2543 else if (no_linkage_check (TREE_TYPE (decl), /*relaxed_p=*/true))
2544 /* DR 757: A type without linkage shall not be used as the type of a
2545 variable or function with linkage, unless
2546 o the variable or function has extern "C" linkage (7.5 [dcl.link]), or
2547 o the variable or function is not used (3.2 [basic.def.odr]) or is
2548 defined in the same translation unit.
2549
2550 Since non-extern "C" decls need to be defined in the same
2551 translation unit, we can make the type internal. */
2552 constrain_visibility (decl, VISIBILITY_ANON, false);
2553
2554 /* If visibility changed and DECL already has DECL_RTL, ensure
2555 symbol flags are updated. */
2556 if ((DECL_VISIBILITY (decl) != orig_visibility
2557 || DECL_VISIBILITY_SPECIFIED (decl) != orig_visibility_specified)
2558 && ((VAR_P (decl) && TREE_STATIC (decl))
2559 || TREE_CODE (decl) == FUNCTION_DECL)
2560 && DECL_RTL_SET_P (decl))
2561 make_decl_rtl (decl);
2562 }
2563
2564 /* By default, static data members and function members receive
2565 the visibility of their containing class. */
2566
2567 static void
determine_visibility_from_class(tree decl,tree class_type)2568 determine_visibility_from_class (tree decl, tree class_type)
2569 {
2570 if (DECL_VISIBILITY_SPECIFIED (decl))
2571 return;
2572
2573 if (determine_hidden_inline (decl))
2574 DECL_VISIBILITY (decl) = VISIBILITY_HIDDEN;
2575 else
2576 {
2577 /* Default to the class visibility. */
2578 DECL_VISIBILITY (decl) = CLASSTYPE_VISIBILITY (class_type);
2579 DECL_VISIBILITY_SPECIFIED (decl)
2580 = CLASSTYPE_VISIBILITY_SPECIFIED (class_type);
2581 }
2582
2583 /* Give the target a chance to override the visibility associated
2584 with DECL. */
2585 if (VAR_P (decl)
2586 && (DECL_TINFO_P (decl)
2587 || (DECL_VTABLE_OR_VTT_P (decl)
2588 /* Construction virtual tables are not exported because
2589 they cannot be referred to from other object files;
2590 their name is not standardized by the ABI. */
2591 && !DECL_CONSTRUCTION_VTABLE_P (decl)))
2592 && TREE_PUBLIC (decl)
2593 && !DECL_REALLY_EXTERN (decl)
2594 && !CLASSTYPE_VISIBILITY_SPECIFIED (class_type))
2595 targetm.cxx.determine_class_data_visibility (decl);
2596 }
2597
2598 /* Returns true iff DECL is an inline that should get hidden visibility
2599 because of -fvisibility-inlines-hidden. */
2600
2601 static bool
determine_hidden_inline(tree decl)2602 determine_hidden_inline (tree decl)
2603 {
2604 return (visibility_options.inlines_hidden
2605 /* Don't do this for inline templates; specializations might not be
2606 inline, and we don't want them to inherit the hidden
2607 visibility. We'll set it here for all inline instantiations. */
2608 && !processing_template_decl
2609 && TREE_CODE (decl) == FUNCTION_DECL
2610 && DECL_DECLARED_INLINE_P (decl)
2611 && (! DECL_LANG_SPECIFIC (decl)
2612 || ! DECL_EXPLICIT_INSTANTIATION (decl)));
2613 }
2614
2615 /* Constrain the visibility of a class TYPE based on the visibility of its
2616 field types. Warn if any fields require lesser visibility. */
2617
2618 void
constrain_class_visibility(tree type)2619 constrain_class_visibility (tree type)
2620 {
2621 tree binfo;
2622 tree t;
2623 int i;
2624
2625 int vis = type_visibility (type);
2626
2627 if (vis == VISIBILITY_ANON
2628 || DECL_IN_SYSTEM_HEADER (TYPE_MAIN_DECL (type)))
2629 return;
2630
2631 /* Don't warn about visibility if the class has explicit visibility. */
2632 if (CLASSTYPE_VISIBILITY_SPECIFIED (type))
2633 vis = VISIBILITY_INTERNAL;
2634
2635 for (t = TYPE_FIELDS (type); t; t = DECL_CHAIN (t))
2636 if (TREE_CODE (t) == FIELD_DECL && TREE_TYPE (t) != error_mark_node
2637 && !DECL_ARTIFICIAL (t))
2638 {
2639 tree ftype = strip_pointer_or_array_types (TREE_TYPE (t));
2640 int subvis = type_visibility (ftype);
2641
2642 if (subvis == VISIBILITY_ANON)
2643 {
2644 if (!in_main_input_context())
2645 {
2646 tree nlt = no_linkage_check (ftype, /*relaxed_p=*/false);
2647 if (nlt)
2648 {
2649 if (same_type_p (TREE_TYPE (t), nlt))
2650 warning (OPT_Wsubobject_linkage, "\
2651 %qT has a field %qD whose type has no linkage",
2652 type, t);
2653 else
2654 warning (OPT_Wsubobject_linkage, "\
2655 %qT has a field %qD whose type depends on the type %qT which has no linkage",
2656 type, t, nlt);
2657 }
2658 else
2659 warning (OPT_Wsubobject_linkage, "\
2660 %qT has a field %qD whose type uses the anonymous namespace",
2661 type, t);
2662 }
2663 }
2664 else if (MAYBE_CLASS_TYPE_P (ftype)
2665 && vis < VISIBILITY_HIDDEN
2666 && subvis >= VISIBILITY_HIDDEN)
2667 warning (OPT_Wattributes, "\
2668 %qT declared with greater visibility than the type of its field %qD",
2669 type, t);
2670 }
2671
2672 binfo = TYPE_BINFO (type);
2673 for (i = 0; BINFO_BASE_ITERATE (binfo, i, t); ++i)
2674 {
2675 int subvis = type_visibility (TREE_TYPE (t));
2676
2677 if (subvis == VISIBILITY_ANON)
2678 {
2679 if (!in_main_input_context())
2680 {
2681 tree nlt = no_linkage_check (TREE_TYPE (t), /*relaxed_p=*/false);
2682 if (nlt)
2683 {
2684 if (same_type_p (TREE_TYPE (t), nlt))
2685 warning (OPT_Wsubobject_linkage, "\
2686 %qT has a base %qT whose type has no linkage",
2687 type, TREE_TYPE (t));
2688 else
2689 warning (OPT_Wsubobject_linkage, "\
2690 %qT has a base %qT whose type depends on the type %qT which has no linkage",
2691 type, TREE_TYPE (t), nlt);
2692 }
2693 else
2694 warning (OPT_Wsubobject_linkage, "\
2695 %qT has a base %qT whose type uses the anonymous namespace",
2696 type, TREE_TYPE (t));
2697 }
2698 }
2699 else if (vis < VISIBILITY_HIDDEN
2700 && subvis >= VISIBILITY_HIDDEN)
2701 warning (OPT_Wattributes, "\
2702 %qT declared with greater visibility than its base %qT",
2703 type, TREE_TYPE (t));
2704 }
2705 }
2706
2707 /* Functions for adjusting the visibility of a tagged type and its nested
2708 types and declarations when it gets a name for linkage purposes from a
2709 typedef. */
2710
2711 static void bt_reset_linkage_1 (binding_entry, void *);
2712 static void bt_reset_linkage_2 (binding_entry, void *);
2713
2714 /* First reset the visibility of all the types. */
2715
2716 static void
reset_type_linkage_1(tree type)2717 reset_type_linkage_1 (tree type)
2718 {
2719 set_linkage_according_to_type (type, TYPE_MAIN_DECL (type));
2720 if (CLASS_TYPE_P (type))
2721 binding_table_foreach (CLASSTYPE_NESTED_UTDS (type),
2722 bt_reset_linkage_1, NULL);
2723 }
2724 static void
bt_reset_linkage_1(binding_entry b,void *)2725 bt_reset_linkage_1 (binding_entry b, void */*data*/)
2726 {
2727 reset_type_linkage_1 (b->type);
2728 }
2729
2730 /* Then reset the visibility of any static data members or member
2731 functions that use those types. */
2732
2733 static void
reset_decl_linkage(tree decl)2734 reset_decl_linkage (tree decl)
2735 {
2736 if (TREE_PUBLIC (decl))
2737 return;
2738 if (DECL_CLONED_FUNCTION_P (decl))
2739 return;
2740 TREE_PUBLIC (decl) = true;
2741 DECL_INTERFACE_KNOWN (decl) = false;
2742 determine_visibility (decl);
2743 tentative_decl_linkage (decl);
2744 }
2745
2746 static void
reset_type_linkage_2(tree type)2747 reset_type_linkage_2 (tree type)
2748 {
2749 if (CLASS_TYPE_P (type))
2750 {
2751 if (tree vt = CLASSTYPE_VTABLES (type))
2752 {
2753 tree name = mangle_vtbl_for_type (type);
2754 DECL_NAME (vt) = name;
2755 SET_DECL_ASSEMBLER_NAME (vt, name);
2756 reset_decl_linkage (vt);
2757 }
2758 if (tree ti = CLASSTYPE_TYPEINFO_VAR (type))
2759 {
2760 tree name = mangle_typeinfo_for_type (type);
2761 DECL_NAME (ti) = name;
2762 SET_DECL_ASSEMBLER_NAME (ti, name);
2763 TREE_TYPE (name) = type;
2764 reset_decl_linkage (ti);
2765 }
2766 for (tree m = TYPE_FIELDS (type); m; m = DECL_CHAIN (m))
2767 {
2768 tree mem = STRIP_TEMPLATE (m);
2769 if (TREE_CODE (mem) == VAR_DECL || TREE_CODE (mem) == FUNCTION_DECL)
2770 reset_decl_linkage (mem);
2771 }
2772 binding_table_foreach (CLASSTYPE_NESTED_UTDS (type),
2773 bt_reset_linkage_2, NULL);
2774 }
2775 }
2776
2777 static void
bt_reset_linkage_2(binding_entry b,void *)2778 bt_reset_linkage_2 (binding_entry b, void */*data*/)
2779 {
2780 reset_type_linkage_2 (b->type);
2781 }
2782 void
reset_type_linkage(tree type)2783 reset_type_linkage (tree type)
2784 {
2785 reset_type_linkage_1 (type);
2786 reset_type_linkage_2 (type);
2787 }
2788
2789 /* Set up our initial idea of what the linkage of DECL should be. */
2790
2791 void
tentative_decl_linkage(tree decl)2792 tentative_decl_linkage (tree decl)
2793 {
2794 if (DECL_INTERFACE_KNOWN (decl))
2795 /* We've already made a decision as to how this function will
2796 be handled. */;
2797 else if (vague_linkage_p (decl))
2798 {
2799 if (TREE_CODE (decl) == FUNCTION_DECL
2800 && decl_defined_p (decl))
2801 {
2802 DECL_EXTERNAL (decl) = 1;
2803 DECL_NOT_REALLY_EXTERN (decl) = 1;
2804 note_vague_linkage_fn (decl);
2805 /* A non-template inline function with external linkage will
2806 always be COMDAT. As we must eventually determine the
2807 linkage of all functions, and as that causes writes to
2808 the data mapped in from the PCH file, it's advantageous
2809 to mark the functions at this point. */
2810 if (DECL_DECLARED_INLINE_P (decl)
2811 && (!DECL_IMPLICIT_INSTANTIATION (decl)
2812 || DECL_DEFAULTED_FN (decl)))
2813 {
2814 /* This function must have external linkage, as
2815 otherwise DECL_INTERFACE_KNOWN would have been
2816 set. */
2817 gcc_assert (TREE_PUBLIC (decl));
2818 comdat_linkage (decl);
2819 DECL_INTERFACE_KNOWN (decl) = 1;
2820 }
2821 }
2822 else if (VAR_P (decl))
2823 maybe_commonize_var (decl);
2824 }
2825 }
2826
2827 /* DECL is a FUNCTION_DECL or VAR_DECL. If the object file linkage
2828 for DECL has not already been determined, do so now by setting
2829 DECL_EXTERNAL, DECL_COMDAT and other related flags. Until this
2830 function is called entities with vague linkage whose definitions
2831 are available must have TREE_PUBLIC set.
2832
2833 If this function decides to place DECL in COMDAT, it will set
2834 appropriate flags -- but will not clear DECL_EXTERNAL. It is up to
2835 the caller to decide whether or not to clear DECL_EXTERNAL. Some
2836 callers defer that decision until it is clear that DECL is actually
2837 required. */
2838
2839 void
import_export_decl(tree decl)2840 import_export_decl (tree decl)
2841 {
2842 int emit_p;
2843 bool comdat_p;
2844 bool import_p;
2845 tree class_type = NULL_TREE;
2846
2847 if (DECL_INTERFACE_KNOWN (decl))
2848 return;
2849
2850 /* We cannot determine what linkage to give to an entity with vague
2851 linkage until the end of the file. For example, a virtual table
2852 for a class will be defined if and only if the key method is
2853 defined in this translation unit. As a further example, consider
2854 that when compiling a translation unit that uses PCH file with
2855 "-frepo" it would be incorrect to make decisions about what
2856 entities to emit when building the PCH; those decisions must be
2857 delayed until the repository information has been processed. */
2858 gcc_assert (at_eof);
2859 /* Object file linkage for explicit instantiations is handled in
2860 mark_decl_instantiated. For static variables in functions with
2861 vague linkage, maybe_commonize_var is used.
2862
2863 Therefore, the only declarations that should be provided to this
2864 function are those with external linkage that are:
2865
2866 * implicit instantiations of function templates
2867
2868 * inline function
2869
2870 * implicit instantiations of static data members of class
2871 templates
2872
2873 * virtual tables
2874
2875 * typeinfo objects
2876
2877 Furthermore, all entities that reach this point must have a
2878 definition available in this translation unit.
2879
2880 The following assertions check these conditions. */
2881 gcc_assert (VAR_OR_FUNCTION_DECL_P (decl));
2882 /* Any code that creates entities with TREE_PUBLIC cleared should
2883 also set DECL_INTERFACE_KNOWN. */
2884 gcc_assert (TREE_PUBLIC (decl));
2885 if (TREE_CODE (decl) == FUNCTION_DECL)
2886 gcc_assert (DECL_IMPLICIT_INSTANTIATION (decl)
2887 || DECL_FRIEND_PSEUDO_TEMPLATE_INSTANTIATION (decl)
2888 || DECL_DECLARED_INLINE_P (decl));
2889 else
2890 gcc_assert (DECL_IMPLICIT_INSTANTIATION (decl)
2891 || DECL_VTABLE_OR_VTT_P (decl)
2892 || DECL_TINFO_P (decl));
2893 /* Check that a definition of DECL is available in this translation
2894 unit. */
2895 gcc_assert (!DECL_REALLY_EXTERN (decl));
2896
2897 /* Assume that DECL will not have COMDAT linkage. */
2898 comdat_p = false;
2899 /* Assume that DECL will not be imported into this translation
2900 unit. */
2901 import_p = false;
2902
2903 /* See if the repository tells us whether or not to emit DECL in
2904 this translation unit. */
2905 emit_p = repo_emit_p (decl);
2906 if (emit_p == 0)
2907 import_p = true;
2908 else if (emit_p == 1)
2909 {
2910 /* The repository indicates that this entity should be defined
2911 here. Make sure the back end honors that request. */
2912 mark_needed (decl);
2913 /* Output the definition as an ordinary strong definition. */
2914 DECL_EXTERNAL (decl) = 0;
2915 DECL_INTERFACE_KNOWN (decl) = 1;
2916 return;
2917 }
2918
2919 if (import_p)
2920 /* We have already decided what to do with this DECL; there is no
2921 need to check anything further. */
2922 ;
2923 else if (VAR_P (decl) && DECL_VTABLE_OR_VTT_P (decl))
2924 {
2925 class_type = DECL_CONTEXT (decl);
2926 import_export_class (class_type);
2927 if (CLASSTYPE_INTERFACE_KNOWN (class_type)
2928 && CLASSTYPE_INTERFACE_ONLY (class_type))
2929 import_p = true;
2930 else if ((!flag_weak || TARGET_WEAK_NOT_IN_ARCHIVE_TOC)
2931 && !CLASSTYPE_USE_TEMPLATE (class_type)
2932 && CLASSTYPE_KEY_METHOD (class_type)
2933 && !DECL_DECLARED_INLINE_P (CLASSTYPE_KEY_METHOD (class_type)))
2934 /* The ABI requires that all virtual tables be emitted with
2935 COMDAT linkage. However, on systems where COMDAT symbols
2936 don't show up in the table of contents for a static
2937 archive, or on systems without weak symbols (where we
2938 approximate COMDAT linkage by using internal linkage), the
2939 linker will report errors about undefined symbols because
2940 it will not see the virtual table definition. Therefore,
2941 in the case that we know that the virtual table will be
2942 emitted in only one translation unit, we make the virtual
2943 table an ordinary definition with external linkage. */
2944 DECL_EXTERNAL (decl) = 0;
2945 else if (CLASSTYPE_INTERFACE_KNOWN (class_type))
2946 {
2947 /* CLASS_TYPE is being exported from this translation unit,
2948 so DECL should be defined here. */
2949 if (!flag_weak && CLASSTYPE_EXPLICIT_INSTANTIATION (class_type))
2950 /* If a class is declared in a header with the "extern
2951 template" extension, then it will not be instantiated,
2952 even in translation units that would normally require
2953 it. Often such classes are explicitly instantiated in
2954 one translation unit. Therefore, the explicit
2955 instantiation must be made visible to other translation
2956 units. */
2957 DECL_EXTERNAL (decl) = 0;
2958 else
2959 {
2960 /* The generic C++ ABI says that class data is always
2961 COMDAT, even if there is a key function. Some
2962 variants (e.g., the ARM EABI) says that class data
2963 only has COMDAT linkage if the class data might be
2964 emitted in more than one translation unit. When the
2965 key method can be inline and is inline, we still have
2966 to arrange for comdat even though
2967 class_data_always_comdat is false. */
2968 if (!CLASSTYPE_KEY_METHOD (class_type)
2969 || DECL_DECLARED_INLINE_P (CLASSTYPE_KEY_METHOD (class_type))
2970 || targetm.cxx.class_data_always_comdat ())
2971 {
2972 /* The ABI requires COMDAT linkage. Normally, we
2973 only emit COMDAT things when they are needed;
2974 make sure that we realize that this entity is
2975 indeed needed. */
2976 comdat_p = true;
2977 mark_needed (decl);
2978 }
2979 }
2980 }
2981 else if (!flag_implicit_templates
2982 && CLASSTYPE_IMPLICIT_INSTANTIATION (class_type))
2983 import_p = true;
2984 else
2985 comdat_p = true;
2986 }
2987 else if (VAR_P (decl) && DECL_TINFO_P (decl))
2988 {
2989 tree type = TREE_TYPE (DECL_NAME (decl));
2990 if (CLASS_TYPE_P (type))
2991 {
2992 class_type = type;
2993 import_export_class (type);
2994 if (CLASSTYPE_INTERFACE_KNOWN (type)
2995 && TYPE_POLYMORPHIC_P (type)
2996 && CLASSTYPE_INTERFACE_ONLY (type)
2997 /* If -fno-rtti was specified, then we cannot be sure
2998 that RTTI information will be emitted with the
2999 virtual table of the class, so we must emit it
3000 wherever it is used. */
3001 && flag_rtti)
3002 import_p = true;
3003 else
3004 {
3005 if (CLASSTYPE_INTERFACE_KNOWN (type)
3006 && !CLASSTYPE_INTERFACE_ONLY (type))
3007 {
3008 comdat_p = (targetm.cxx.class_data_always_comdat ()
3009 || (CLASSTYPE_KEY_METHOD (type)
3010 && DECL_DECLARED_INLINE_P (CLASSTYPE_KEY_METHOD (type))));
3011 mark_needed (decl);
3012 if (!flag_weak)
3013 {
3014 comdat_p = false;
3015 DECL_EXTERNAL (decl) = 0;
3016 }
3017 }
3018 else
3019 comdat_p = true;
3020 }
3021 }
3022 else
3023 comdat_p = true;
3024 }
3025 else if (DECL_TEMPLOID_INSTANTIATION (decl))
3026 {
3027 /* DECL is an implicit instantiation of a function or static
3028 data member. */
3029 if ((flag_implicit_templates
3030 && !flag_use_repository)
3031 || (flag_implicit_inline_templates
3032 && TREE_CODE (decl) == FUNCTION_DECL
3033 && DECL_DECLARED_INLINE_P (decl)))
3034 comdat_p = true;
3035 else
3036 /* If we are not implicitly generating templates, then mark
3037 this entity as undefined in this translation unit. */
3038 import_p = true;
3039 }
3040 else if (DECL_FUNCTION_MEMBER_P (decl))
3041 {
3042 if (!DECL_DECLARED_INLINE_P (decl))
3043 {
3044 tree ctype = DECL_CONTEXT (decl);
3045 import_export_class (ctype);
3046 if (CLASSTYPE_INTERFACE_KNOWN (ctype))
3047 {
3048 DECL_NOT_REALLY_EXTERN (decl)
3049 = ! (CLASSTYPE_INTERFACE_ONLY (ctype)
3050 || (DECL_DECLARED_INLINE_P (decl)
3051 && ! flag_implement_inlines
3052 && !DECL_VINDEX (decl)));
3053
3054 if (!DECL_NOT_REALLY_EXTERN (decl))
3055 DECL_EXTERNAL (decl) = 1;
3056
3057 /* Always make artificials weak. */
3058 if (DECL_ARTIFICIAL (decl) && flag_weak)
3059 comdat_p = true;
3060 else
3061 maybe_make_one_only (decl);
3062 }
3063 }
3064 else
3065 comdat_p = true;
3066 }
3067 else
3068 comdat_p = true;
3069
3070 if (import_p)
3071 {
3072 /* If we are importing DECL into this translation unit, mark is
3073 an undefined here. */
3074 DECL_EXTERNAL (decl) = 1;
3075 DECL_NOT_REALLY_EXTERN (decl) = 0;
3076 }
3077 else if (comdat_p)
3078 {
3079 /* If we decided to put DECL in COMDAT, mark it accordingly at
3080 this point. */
3081 comdat_linkage (decl);
3082 }
3083
3084 DECL_INTERFACE_KNOWN (decl) = 1;
3085 }
3086
3087 /* Return an expression that performs the destruction of DECL, which
3088 must be a VAR_DECL whose type has a non-trivial destructor, or is
3089 an array whose (innermost) elements have a non-trivial destructor. */
3090
3091 tree
build_cleanup(tree decl)3092 build_cleanup (tree decl)
3093 {
3094 tree clean = cxx_maybe_build_cleanup (decl, tf_warning_or_error);
3095 gcc_assert (clean != NULL_TREE);
3096 return clean;
3097 }
3098
3099 /* Returns the initialization guard variable for the variable DECL,
3100 which has static storage duration. */
3101
3102 tree
get_guard(tree decl)3103 get_guard (tree decl)
3104 {
3105 tree sname;
3106 tree guard;
3107
3108 sname = mangle_guard_variable (decl);
3109 guard = get_global_binding (sname);
3110 if (! guard)
3111 {
3112 tree guard_type;
3113
3114 /* We use a type that is big enough to contain a mutex as well
3115 as an integer counter. */
3116 guard_type = targetm.cxx.guard_type ();
3117 guard = build_decl (DECL_SOURCE_LOCATION (decl),
3118 VAR_DECL, sname, guard_type);
3119
3120 /* The guard should have the same linkage as what it guards. */
3121 TREE_PUBLIC (guard) = TREE_PUBLIC (decl);
3122 TREE_STATIC (guard) = TREE_STATIC (decl);
3123 DECL_COMMON (guard) = DECL_COMMON (decl);
3124 DECL_COMDAT (guard) = DECL_COMDAT (decl);
3125 CP_DECL_THREAD_LOCAL_P (guard) = CP_DECL_THREAD_LOCAL_P (decl);
3126 set_decl_tls_model (guard, DECL_TLS_MODEL (decl));
3127 if (DECL_ONE_ONLY (decl))
3128 make_decl_one_only (guard, cxx_comdat_group (guard));
3129 if (TREE_PUBLIC (decl))
3130 DECL_WEAK (guard) = DECL_WEAK (decl);
3131 DECL_VISIBILITY (guard) = DECL_VISIBILITY (decl);
3132 DECL_VISIBILITY_SPECIFIED (guard) = DECL_VISIBILITY_SPECIFIED (decl);
3133
3134 DECL_ARTIFICIAL (guard) = 1;
3135 DECL_IGNORED_P (guard) = 1;
3136 TREE_USED (guard) = 1;
3137 pushdecl_top_level_and_finish (guard, NULL_TREE);
3138 }
3139 return guard;
3140 }
3141
3142 /* Return an atomic load of src with the appropriate memory model. */
3143
3144 static tree
build_atomic_load_byte(tree src,HOST_WIDE_INT model)3145 build_atomic_load_byte (tree src, HOST_WIDE_INT model)
3146 {
3147 tree ptr_type = build_pointer_type (char_type_node);
3148 tree mem_model = build_int_cst (integer_type_node, model);
3149 tree t, addr, val;
3150 unsigned int size;
3151 int fncode;
3152
3153 size = tree_to_uhwi (TYPE_SIZE_UNIT (char_type_node));
3154
3155 fncode = BUILT_IN_ATOMIC_LOAD_N + exact_log2 (size) + 1;
3156 t = builtin_decl_implicit ((enum built_in_function) fncode);
3157
3158 addr = build1 (ADDR_EXPR, ptr_type, src);
3159 val = build_call_expr (t, 2, addr, mem_model);
3160 return val;
3161 }
3162
3163 /* Return those bits of the GUARD variable that should be set when the
3164 guarded entity is actually initialized. */
3165
3166 static tree
get_guard_bits(tree guard)3167 get_guard_bits (tree guard)
3168 {
3169 if (!targetm.cxx.guard_mask_bit ())
3170 {
3171 /* We only set the first byte of the guard, in order to leave room
3172 for a mutex in the high-order bits. */
3173 guard = build1 (ADDR_EXPR,
3174 build_pointer_type (TREE_TYPE (guard)),
3175 guard);
3176 guard = build1 (NOP_EXPR,
3177 build_pointer_type (char_type_node),
3178 guard);
3179 guard = build1 (INDIRECT_REF, char_type_node, guard);
3180 }
3181
3182 return guard;
3183 }
3184
3185 /* Return an expression which determines whether or not the GUARD
3186 variable has already been initialized. */
3187
3188 tree
get_guard_cond(tree guard,bool thread_safe)3189 get_guard_cond (tree guard, bool thread_safe)
3190 {
3191 tree guard_value;
3192
3193 if (!thread_safe)
3194 guard = get_guard_bits (guard);
3195 else
3196 guard = build_atomic_load_byte (guard, MEMMODEL_ACQUIRE);
3197
3198 /* Mask off all but the low bit. */
3199 if (targetm.cxx.guard_mask_bit ())
3200 {
3201 guard_value = integer_one_node;
3202 if (!same_type_p (TREE_TYPE (guard_value), TREE_TYPE (guard)))
3203 guard_value = fold_convert (TREE_TYPE (guard), guard_value);
3204 guard = cp_build_binary_op (input_location,
3205 BIT_AND_EXPR, guard, guard_value,
3206 tf_warning_or_error);
3207 }
3208
3209 guard_value = integer_zero_node;
3210 if (!same_type_p (TREE_TYPE (guard_value), TREE_TYPE (guard)))
3211 guard_value = fold_convert (TREE_TYPE (guard), guard_value);
3212 return cp_build_binary_op (input_location,
3213 EQ_EXPR, guard, guard_value,
3214 tf_warning_or_error);
3215 }
3216
3217 /* Return an expression which sets the GUARD variable, indicating that
3218 the variable being guarded has been initialized. */
3219
3220 tree
set_guard(tree guard)3221 set_guard (tree guard)
3222 {
3223 tree guard_init;
3224
3225 /* Set the GUARD to one. */
3226 guard = get_guard_bits (guard);
3227 guard_init = integer_one_node;
3228 if (!same_type_p (TREE_TYPE (guard_init), TREE_TYPE (guard)))
3229 guard_init = fold_convert (TREE_TYPE (guard), guard_init);
3230 return cp_build_modify_expr (input_location, guard, NOP_EXPR, guard_init,
3231 tf_warning_or_error);
3232 }
3233
3234 /* Returns true iff we can tell that VAR does not have a dynamic
3235 initializer. */
3236
3237 static bool
var_defined_without_dynamic_init(tree var)3238 var_defined_without_dynamic_init (tree var)
3239 {
3240 /* If it's defined in another TU, we can't tell. */
3241 if (DECL_EXTERNAL (var))
3242 return false;
3243 /* If it has a non-trivial destructor, registering the destructor
3244 counts as dynamic initialization. */
3245 if (TYPE_HAS_NONTRIVIAL_DESTRUCTOR (TREE_TYPE (var)))
3246 return false;
3247 /* If it's in this TU, its initializer has been processed, unless
3248 it's a case of self-initialization, then DECL_INITIALIZED_P is
3249 false while the initializer is handled by finish_id_expression. */
3250 if (!DECL_INITIALIZED_P (var))
3251 return false;
3252 /* If it has no initializer or a constant one, it's not dynamic. */
3253 return (!DECL_NONTRIVIALLY_INITIALIZED_P (var)
3254 || DECL_INITIALIZED_BY_CONSTANT_EXPRESSION_P (var));
3255 }
3256
3257 /* Returns true iff VAR is a variable that needs uses to be
3258 wrapped for possible dynamic initialization. */
3259
3260 static bool
var_needs_tls_wrapper(tree var)3261 var_needs_tls_wrapper (tree var)
3262 {
3263 return (!error_operand_p (var)
3264 && CP_DECL_THREAD_LOCAL_P (var)
3265 && !DECL_GNU_TLS_P (var)
3266 && !DECL_FUNCTION_SCOPE_P (var)
3267 && !var_defined_without_dynamic_init (var));
3268 }
3269
3270 /* Get the FUNCTION_DECL for the shared TLS init function for this
3271 translation unit. */
3272
3273 static tree
get_local_tls_init_fn(void)3274 get_local_tls_init_fn (void)
3275 {
3276 tree sname = get_identifier ("__tls_init");
3277 tree fn = get_global_binding (sname);
3278 if (!fn)
3279 {
3280 fn = build_lang_decl (FUNCTION_DECL, sname,
3281 build_function_type (void_type_node,
3282 void_list_node));
3283 SET_DECL_LANGUAGE (fn, lang_c);
3284 TREE_PUBLIC (fn) = false;
3285 DECL_ARTIFICIAL (fn) = true;
3286 mark_used (fn);
3287 set_global_binding (fn);
3288 }
3289 return fn;
3290 }
3291
3292 /* Get a FUNCTION_DECL for the init function for the thread_local
3293 variable VAR. The init function will be an alias to the function
3294 that initializes all the non-local TLS variables in the translation
3295 unit. The init function is only used by the wrapper function. */
3296
3297 static tree
get_tls_init_fn(tree var)3298 get_tls_init_fn (tree var)
3299 {
3300 /* Only C++11 TLS vars need this init fn. */
3301 if (!var_needs_tls_wrapper (var))
3302 return NULL_TREE;
3303
3304 /* If -fno-extern-tls-init, assume that we don't need to call
3305 a tls init function for a variable defined in another TU. */
3306 if (!flag_extern_tls_init && DECL_EXTERNAL (var))
3307 return NULL_TREE;
3308
3309 /* If the variable is internal, or if we can't generate aliases,
3310 call the local init function directly. */
3311 if (!TREE_PUBLIC (var) || !TARGET_SUPPORTS_ALIASES)
3312 return get_local_tls_init_fn ();
3313
3314 tree sname = mangle_tls_init_fn (var);
3315 tree fn = get_global_binding (sname);
3316 if (!fn)
3317 {
3318 fn = build_lang_decl (FUNCTION_DECL, sname,
3319 build_function_type (void_type_node,
3320 void_list_node));
3321 SET_DECL_LANGUAGE (fn, lang_c);
3322 TREE_PUBLIC (fn) = TREE_PUBLIC (var);
3323 DECL_ARTIFICIAL (fn) = true;
3324 DECL_COMDAT (fn) = DECL_COMDAT (var);
3325 DECL_EXTERNAL (fn) = DECL_EXTERNAL (var);
3326 if (DECL_ONE_ONLY (var))
3327 make_decl_one_only (fn, cxx_comdat_group (fn));
3328 if (TREE_PUBLIC (var))
3329 {
3330 tree obtype = strip_array_types (non_reference (TREE_TYPE (var)));
3331 /* If the variable is defined somewhere else and might have static
3332 initialization, make the init function a weak reference. */
3333 if ((!TYPE_NEEDS_CONSTRUCTING (obtype)
3334 || TYPE_HAS_CONSTEXPR_CTOR (obtype)
3335 || TYPE_HAS_TRIVIAL_DFLT (obtype))
3336 && TYPE_HAS_TRIVIAL_DESTRUCTOR (obtype)
3337 && DECL_EXTERNAL (var))
3338 declare_weak (fn);
3339 else
3340 DECL_WEAK (fn) = DECL_WEAK (var);
3341 }
3342 DECL_VISIBILITY (fn) = DECL_VISIBILITY (var);
3343 DECL_VISIBILITY_SPECIFIED (fn) = DECL_VISIBILITY_SPECIFIED (var);
3344 DECL_DLLIMPORT_P (fn) = DECL_DLLIMPORT_P (var);
3345 DECL_IGNORED_P (fn) = 1;
3346 mark_used (fn);
3347
3348 DECL_BEFRIENDING_CLASSES (fn) = var;
3349
3350 set_global_binding (fn);
3351 }
3352 return fn;
3353 }
3354
3355 /* Get a FUNCTION_DECL for the init wrapper function for the thread_local
3356 variable VAR. The wrapper function calls the init function (if any) for
3357 VAR and then returns a reference to VAR. The wrapper function is used
3358 in place of VAR everywhere VAR is mentioned. */
3359
3360 tree
get_tls_wrapper_fn(tree var)3361 get_tls_wrapper_fn (tree var)
3362 {
3363 /* Only C++11 TLS vars need this wrapper fn. */
3364 if (!var_needs_tls_wrapper (var))
3365 return NULL_TREE;
3366
3367 tree sname = mangle_tls_wrapper_fn (var);
3368 tree fn = get_global_binding (sname);
3369 if (!fn)
3370 {
3371 /* A named rvalue reference is an lvalue, so the wrapper should
3372 always return an lvalue reference. */
3373 tree type = non_reference (TREE_TYPE (var));
3374 type = build_reference_type (type);
3375 tree fntype = build_function_type (type, void_list_node);
3376 fn = build_lang_decl (FUNCTION_DECL, sname, fntype);
3377 SET_DECL_LANGUAGE (fn, lang_c);
3378 TREE_PUBLIC (fn) = TREE_PUBLIC (var);
3379 DECL_ARTIFICIAL (fn) = true;
3380 DECL_IGNORED_P (fn) = 1;
3381 /* The wrapper is inline and emitted everywhere var is used. */
3382 DECL_DECLARED_INLINE_P (fn) = true;
3383 if (TREE_PUBLIC (var))
3384 {
3385 comdat_linkage (fn);
3386 #ifdef HAVE_GAS_HIDDEN
3387 /* Make the wrapper bind locally; there's no reason to share
3388 the wrapper between multiple shared objects. */
3389 DECL_VISIBILITY (fn) = VISIBILITY_INTERNAL;
3390 DECL_VISIBILITY_SPECIFIED (fn) = true;
3391 #endif
3392 }
3393 if (!TREE_PUBLIC (fn))
3394 DECL_INTERFACE_KNOWN (fn) = true;
3395 mark_used (fn);
3396 note_vague_linkage_fn (fn);
3397
3398 #if 0
3399 /* We want CSE to commonize calls to the wrapper, but marking it as
3400 pure is unsafe since it has side-effects. I guess we need a new
3401 ECF flag even weaker than ECF_PURE. FIXME! */
3402 DECL_PURE_P (fn) = true;
3403 #endif
3404
3405 DECL_BEFRIENDING_CLASSES (fn) = var;
3406
3407 set_global_binding (fn);
3408 }
3409 return fn;
3410 }
3411
3412 /* At EOF, generate the definition for the TLS wrapper function FN:
3413
3414 T& var_wrapper() {
3415 if (init_fn) init_fn();
3416 return var;
3417 } */
3418
3419 static void
generate_tls_wrapper(tree fn)3420 generate_tls_wrapper (tree fn)
3421 {
3422 tree var = DECL_BEFRIENDING_CLASSES (fn);
3423
3424 start_preparsed_function (fn, NULL_TREE, SF_DEFAULT | SF_PRE_PARSED);
3425 tree body = begin_function_body ();
3426 /* Only call the init fn if there might be one. */
3427 if (tree init_fn = get_tls_init_fn (var))
3428 {
3429 tree if_stmt = NULL_TREE;
3430 /* If init_fn is a weakref, make sure it exists before calling. */
3431 if (lookup_attribute ("weak", DECL_ATTRIBUTES (init_fn)))
3432 {
3433 if_stmt = begin_if_stmt ();
3434 tree addr = cp_build_addr_expr (init_fn, tf_warning_or_error);
3435 tree cond = cp_build_binary_op (DECL_SOURCE_LOCATION (var),
3436 NE_EXPR, addr, nullptr_node,
3437 tf_warning_or_error);
3438 finish_if_stmt_cond (cond, if_stmt);
3439 }
3440 finish_expr_stmt (build_cxx_call
3441 (init_fn, 0, NULL, tf_warning_or_error));
3442 if (if_stmt)
3443 {
3444 finish_then_clause (if_stmt);
3445 finish_if_stmt (if_stmt);
3446 }
3447 }
3448 else
3449 /* If there's no initialization, the wrapper is a constant function. */
3450 TREE_READONLY (fn) = true;
3451 finish_return_stmt (convert_from_reference (var));
3452 finish_function_body (body);
3453 expand_or_defer_fn (finish_function (/*inline_p=*/false));
3454 }
3455
3456 /* Start the process of running a particular set of global constructors
3457 or destructors. Subroutine of do_[cd]tors. Also called from
3458 vtv_start_verification_constructor_init_function. */
3459
3460 static tree
start_objects(int method_type,int initp)3461 start_objects (int method_type, int initp)
3462 {
3463 tree body;
3464 tree fndecl;
3465 char type[14];
3466
3467 /* Make ctor or dtor function. METHOD_TYPE may be 'I' or 'D'. */
3468
3469 if (initp != DEFAULT_INIT_PRIORITY)
3470 {
3471 char joiner;
3472
3473 #ifdef JOINER
3474 joiner = JOINER;
3475 #else
3476 joiner = '_';
3477 #endif
3478
3479 sprintf (type, "sub_%c%c%.5u", method_type, joiner, initp);
3480 }
3481 else
3482 sprintf (type, "sub_%c", method_type);
3483
3484 fndecl = build_lang_decl (FUNCTION_DECL,
3485 get_file_function_name (type),
3486 build_function_type_list (void_type_node,
3487 NULL_TREE));
3488 start_preparsed_function (fndecl, /*attrs=*/NULL_TREE, SF_PRE_PARSED);
3489
3490 TREE_PUBLIC (current_function_decl) = 0;
3491
3492 /* Mark as artificial because it's not explicitly in the user's
3493 source code. */
3494 DECL_ARTIFICIAL (current_function_decl) = 1;
3495
3496 /* Mark this declaration as used to avoid spurious warnings. */
3497 TREE_USED (current_function_decl) = 1;
3498
3499 /* Mark this function as a global constructor or destructor. */
3500 if (method_type == 'I')
3501 DECL_GLOBAL_CTOR_P (current_function_decl) = 1;
3502 else
3503 DECL_GLOBAL_DTOR_P (current_function_decl) = 1;
3504
3505 body = begin_compound_stmt (BCS_FN_BODY);
3506
3507 return body;
3508 }
3509
3510 /* Finish the process of running a particular set of global constructors
3511 or destructors. Subroutine of do_[cd]tors. */
3512
3513 static void
finish_objects(int method_type,int initp,tree body)3514 finish_objects (int method_type, int initp, tree body)
3515 {
3516 tree fn;
3517
3518 /* Finish up. */
3519 finish_compound_stmt (body);
3520 fn = finish_function (/*inline_p=*/false);
3521
3522 if (method_type == 'I')
3523 {
3524 DECL_STATIC_CONSTRUCTOR (fn) = 1;
3525 decl_init_priority_insert (fn, initp);
3526 }
3527 else
3528 {
3529 DECL_STATIC_DESTRUCTOR (fn) = 1;
3530 decl_fini_priority_insert (fn, initp);
3531 }
3532
3533 expand_or_defer_fn (fn);
3534 }
3535
3536 /* The names of the parameters to the function created to handle
3537 initializations and destructions for objects with static storage
3538 duration. */
3539 #define INITIALIZE_P_IDENTIFIER "__initialize_p"
3540 #define PRIORITY_IDENTIFIER "__priority"
3541
3542 /* The name of the function we create to handle initializations and
3543 destructions for objects with static storage duration. */
3544 #define SSDF_IDENTIFIER "__static_initialization_and_destruction"
3545
3546 /* The declaration for the __INITIALIZE_P argument. */
3547 static GTY(()) tree initialize_p_decl;
3548
3549 /* The declaration for the __PRIORITY argument. */
3550 static GTY(()) tree priority_decl;
3551
3552 /* The declaration for the static storage duration function. */
3553 static GTY(()) tree ssdf_decl;
3554
3555 /* All the static storage duration functions created in this
3556 translation unit. */
3557 static GTY(()) vec<tree, va_gc> *ssdf_decls;
3558
3559 /* A map from priority levels to information about that priority
3560 level. There may be many such levels, so efficient lookup is
3561 important. */
3562 static splay_tree priority_info_map;
3563
3564 /* Begins the generation of the function that will handle all
3565 initialization and destruction of objects with static storage
3566 duration. The function generated takes two parameters of type
3567 `int': __INITIALIZE_P and __PRIORITY. If __INITIALIZE_P is
3568 nonzero, it performs initializations. Otherwise, it performs
3569 destructions. It only performs those initializations or
3570 destructions with the indicated __PRIORITY. The generated function
3571 returns no value.
3572
3573 It is assumed that this function will only be called once per
3574 translation unit. */
3575
3576 static tree
start_static_storage_duration_function(unsigned count)3577 start_static_storage_duration_function (unsigned count)
3578 {
3579 tree type;
3580 tree body;
3581 char id[sizeof (SSDF_IDENTIFIER) + 1 /* '\0' */ + 32];
3582
3583 /* Create the identifier for this function. It will be of the form
3584 SSDF_IDENTIFIER_<number>. */
3585 sprintf (id, "%s_%u", SSDF_IDENTIFIER, count);
3586
3587 type = build_function_type_list (void_type_node,
3588 integer_type_node, integer_type_node,
3589 NULL_TREE);
3590
3591 /* Create the FUNCTION_DECL itself. */
3592 ssdf_decl = build_lang_decl (FUNCTION_DECL,
3593 get_identifier (id),
3594 type);
3595 TREE_PUBLIC (ssdf_decl) = 0;
3596 DECL_ARTIFICIAL (ssdf_decl) = 1;
3597
3598 /* Put this function in the list of functions to be called from the
3599 static constructors and destructors. */
3600 if (!ssdf_decls)
3601 {
3602 vec_alloc (ssdf_decls, 32);
3603
3604 /* Take this opportunity to initialize the map from priority
3605 numbers to information about that priority level. */
3606 priority_info_map = splay_tree_new (splay_tree_compare_ints,
3607 /*delete_key_fn=*/0,
3608 /*delete_value_fn=*/
3609 (splay_tree_delete_value_fn)
3610 (void (*) (void)) free);
3611
3612 /* We always need to generate functions for the
3613 DEFAULT_INIT_PRIORITY so enter it now. That way when we walk
3614 priorities later, we'll be sure to find the
3615 DEFAULT_INIT_PRIORITY. */
3616 get_priority_info (DEFAULT_INIT_PRIORITY);
3617 }
3618
3619 vec_safe_push (ssdf_decls, ssdf_decl);
3620
3621 /* Create the argument list. */
3622 initialize_p_decl = cp_build_parm_decl
3623 (ssdf_decl, get_identifier (INITIALIZE_P_IDENTIFIER), integer_type_node);
3624 TREE_USED (initialize_p_decl) = 1;
3625 priority_decl = cp_build_parm_decl
3626 (ssdf_decl, get_identifier (PRIORITY_IDENTIFIER), integer_type_node);
3627 TREE_USED (priority_decl) = 1;
3628
3629 DECL_CHAIN (initialize_p_decl) = priority_decl;
3630 DECL_ARGUMENTS (ssdf_decl) = initialize_p_decl;
3631
3632 /* Put the function in the global scope. */
3633 pushdecl (ssdf_decl);
3634
3635 /* Start the function itself. This is equivalent to declaring the
3636 function as:
3637
3638 static void __ssdf (int __initialize_p, init __priority_p);
3639
3640 It is static because we only need to call this function from the
3641 various constructor and destructor functions for this module. */
3642 start_preparsed_function (ssdf_decl,
3643 /*attrs=*/NULL_TREE,
3644 SF_PRE_PARSED);
3645
3646 /* Set up the scope of the outermost block in the function. */
3647 body = begin_compound_stmt (BCS_FN_BODY);
3648
3649 return body;
3650 }
3651
3652 /* Finish the generation of the function which performs initialization
3653 and destruction of objects with static storage duration. After
3654 this point, no more such objects can be created. */
3655
3656 static void
finish_static_storage_duration_function(tree body)3657 finish_static_storage_duration_function (tree body)
3658 {
3659 /* Close out the function. */
3660 finish_compound_stmt (body);
3661 expand_or_defer_fn (finish_function (/*inline_p=*/false));
3662 }
3663
3664 /* Return the information about the indicated PRIORITY level. If no
3665 code to handle this level has yet been generated, generate the
3666 appropriate prologue. */
3667
3668 static priority_info
get_priority_info(int priority)3669 get_priority_info (int priority)
3670 {
3671 priority_info pi;
3672 splay_tree_node n;
3673
3674 n = splay_tree_lookup (priority_info_map,
3675 (splay_tree_key) priority);
3676 if (!n)
3677 {
3678 /* Create a new priority information structure, and insert it
3679 into the map. */
3680 pi = XNEW (struct priority_info_s);
3681 pi->initializations_p = 0;
3682 pi->destructions_p = 0;
3683 splay_tree_insert (priority_info_map,
3684 (splay_tree_key) priority,
3685 (splay_tree_value) pi);
3686 }
3687 else
3688 pi = (priority_info) n->value;
3689
3690 return pi;
3691 }
3692
3693 /* The effective initialization priority of a DECL. */
3694
3695 #define DECL_EFFECTIVE_INIT_PRIORITY(decl) \
3696 ((!DECL_HAS_INIT_PRIORITY_P (decl) || DECL_INIT_PRIORITY (decl) == 0) \
3697 ? DEFAULT_INIT_PRIORITY : DECL_INIT_PRIORITY (decl))
3698
3699 /* Whether a DECL needs a guard to protect it against multiple
3700 initialization. */
3701
3702 #define NEEDS_GUARD_P(decl) (TREE_PUBLIC (decl) && (DECL_COMMON (decl) \
3703 || DECL_ONE_ONLY (decl) \
3704 || DECL_WEAK (decl)))
3705
3706 /* Called from one_static_initialization_or_destruction(),
3707 via walk_tree.
3708 Walks the initializer list of a global variable and looks for
3709 temporary variables (DECL_NAME() == NULL and DECL_ARTIFICIAL != 0)
3710 and that have their DECL_CONTEXT() == NULL.
3711 For each such temporary variable, set their DECL_CONTEXT() to
3712 the current function. This is necessary because otherwise
3713 some optimizers (enabled by -O2 -fprofile-arcs) might crash
3714 when trying to refer to a temporary variable that does not have
3715 it's DECL_CONTECT() properly set. */
3716 static tree
fix_temporary_vars_context_r(tree * node,int *,void *)3717 fix_temporary_vars_context_r (tree *node,
3718 int * /*unused*/,
3719 void * /*unused1*/)
3720 {
3721 gcc_assert (current_function_decl);
3722
3723 if (TREE_CODE (*node) == BIND_EXPR)
3724 {
3725 tree var;
3726
3727 for (var = BIND_EXPR_VARS (*node); var; var = DECL_CHAIN (var))
3728 if (VAR_P (var)
3729 && !DECL_NAME (var)
3730 && DECL_ARTIFICIAL (var)
3731 && !DECL_CONTEXT (var))
3732 DECL_CONTEXT (var) = current_function_decl;
3733 }
3734
3735 return NULL_TREE;
3736 }
3737
3738 /* Set up to handle the initialization or destruction of DECL. If
3739 INITP is nonzero, we are initializing the variable. Otherwise, we
3740 are destroying it. */
3741
3742 static void
one_static_initialization_or_destruction(tree decl,tree init,bool initp)3743 one_static_initialization_or_destruction (tree decl, tree init, bool initp)
3744 {
3745 tree guard_if_stmt = NULL_TREE;
3746 tree guard;
3747
3748 /* If we are supposed to destruct and there's a trivial destructor,
3749 nothing has to be done. */
3750 if (!initp
3751 && TYPE_HAS_TRIVIAL_DESTRUCTOR (TREE_TYPE (decl)))
3752 return;
3753
3754 /* Trick the compiler into thinking we are at the file and line
3755 where DECL was declared so that error-messages make sense, and so
3756 that the debugger will show somewhat sensible file and line
3757 information. */
3758 input_location = DECL_SOURCE_LOCATION (decl);
3759
3760 /* Make sure temporary variables in the initialiser all have
3761 their DECL_CONTEXT() set to a value different from NULL_TREE.
3762 This can happen when global variables initializers are built.
3763 In that case, the DECL_CONTEXT() of the global variables _AND_ of all
3764 the temporary variables that might have been generated in the
3765 accompanying initializers is NULL_TREE, meaning the variables have been
3766 declared in the global namespace.
3767 What we want to do here is to fix that and make sure the DECL_CONTEXT()
3768 of the temporaries are set to the current function decl. */
3769 cp_walk_tree_without_duplicates (&init,
3770 fix_temporary_vars_context_r,
3771 NULL);
3772
3773 /* Because of:
3774
3775 [class.access.spec]
3776
3777 Access control for implicit calls to the constructors,
3778 the conversion functions, or the destructor called to
3779 create and destroy a static data member is performed as
3780 if these calls appeared in the scope of the member's
3781 class.
3782
3783 we pretend we are in a static member function of the class of
3784 which the DECL is a member. */
3785 if (member_p (decl))
3786 {
3787 DECL_CONTEXT (current_function_decl) = DECL_CONTEXT (decl);
3788 DECL_STATIC_FUNCTION_P (current_function_decl) = 1;
3789 }
3790
3791 /* Assume we don't need a guard. */
3792 guard = NULL_TREE;
3793 /* We need a guard if this is an object with external linkage that
3794 might be initialized in more than one place. (For example, a
3795 static data member of a template, when the data member requires
3796 construction.) */
3797 if (NEEDS_GUARD_P (decl))
3798 {
3799 tree guard_cond;
3800
3801 guard = get_guard (decl);
3802
3803 /* When using __cxa_atexit, we just check the GUARD as we would
3804 for a local static. */
3805 if (flag_use_cxa_atexit)
3806 {
3807 /* When using __cxa_atexit, we never try to destroy
3808 anything from a static destructor. */
3809 gcc_assert (initp);
3810 guard_cond = get_guard_cond (guard, false);
3811 }
3812 /* If we don't have __cxa_atexit, then we will be running
3813 destructors from .fini sections, or their equivalents. So,
3814 we need to know how many times we've tried to initialize this
3815 object. We do initializations only if the GUARD is zero,
3816 i.e., if we are the first to initialize the variable. We do
3817 destructions only if the GUARD is one, i.e., if we are the
3818 last to destroy the variable. */
3819 else if (initp)
3820 guard_cond
3821 = cp_build_binary_op (input_location,
3822 EQ_EXPR,
3823 cp_build_unary_op (PREINCREMENT_EXPR,
3824 guard,
3825 /*noconvert=*/true,
3826 tf_warning_or_error),
3827 integer_one_node,
3828 tf_warning_or_error);
3829 else
3830 guard_cond
3831 = cp_build_binary_op (input_location,
3832 EQ_EXPR,
3833 cp_build_unary_op (PREDECREMENT_EXPR,
3834 guard,
3835 /*noconvert=*/true,
3836 tf_warning_or_error),
3837 integer_zero_node,
3838 tf_warning_or_error);
3839
3840 guard_if_stmt = begin_if_stmt ();
3841 finish_if_stmt_cond (guard_cond, guard_if_stmt);
3842 }
3843
3844
3845 /* If we're using __cxa_atexit, we have not already set the GUARD,
3846 so we must do so now. */
3847 if (guard && initp && flag_use_cxa_atexit)
3848 finish_expr_stmt (set_guard (guard));
3849
3850 /* Perform the initialization or destruction. */
3851 if (initp)
3852 {
3853 if (init)
3854 {
3855 finish_expr_stmt (init);
3856 if (sanitize_flags_p (SANITIZE_ADDRESS, decl))
3857 {
3858 varpool_node *vnode = varpool_node::get (decl);
3859 if (vnode)
3860 vnode->dynamically_initialized = 1;
3861 }
3862 }
3863
3864 /* If we're using __cxa_atexit, register a function that calls the
3865 destructor for the object. */
3866 if (flag_use_cxa_atexit)
3867 finish_expr_stmt (register_dtor_fn (decl));
3868 }
3869 else
3870 finish_expr_stmt (build_cleanup (decl));
3871
3872 /* Finish the guard if-stmt, if necessary. */
3873 if (guard)
3874 {
3875 finish_then_clause (guard_if_stmt);
3876 finish_if_stmt (guard_if_stmt);
3877 }
3878
3879 /* Now that we're done with DECL we don't need to pretend to be a
3880 member of its class any longer. */
3881 DECL_CONTEXT (current_function_decl) = NULL_TREE;
3882 DECL_STATIC_FUNCTION_P (current_function_decl) = 0;
3883 }
3884
3885 /* Generate code to do the initialization or destruction of the decls in VARS,
3886 a TREE_LIST of VAR_DECL with static storage duration.
3887 Whether initialization or destruction is performed is specified by INITP. */
3888
3889 static void
do_static_initialization_or_destruction(tree vars,bool initp)3890 do_static_initialization_or_destruction (tree vars, bool initp)
3891 {
3892 tree node, init_if_stmt, cond;
3893
3894 /* Build the outer if-stmt to check for initialization or destruction. */
3895 init_if_stmt = begin_if_stmt ();
3896 cond = initp ? integer_one_node : integer_zero_node;
3897 cond = cp_build_binary_op (input_location,
3898 EQ_EXPR,
3899 initialize_p_decl,
3900 cond,
3901 tf_warning_or_error);
3902 finish_if_stmt_cond (cond, init_if_stmt);
3903
3904 /* To make sure dynamic construction doesn't access globals from other
3905 compilation units where they might not be yet constructed, for
3906 -fsanitize=address insert __asan_before_dynamic_init call that
3907 prevents access to either all global variables that need construction
3908 in other compilation units, or at least those that haven't been
3909 initialized yet. Variables that need dynamic construction in
3910 the current compilation unit are kept accessible. */
3911 if (initp && (flag_sanitize & SANITIZE_ADDRESS))
3912 finish_expr_stmt (asan_dynamic_init_call (/*after_p=*/false));
3913
3914 node = vars;
3915 do {
3916 tree decl = TREE_VALUE (node);
3917 tree priority_if_stmt;
3918 int priority;
3919 priority_info pi;
3920
3921 /* If we don't need a destructor, there's nothing to do. Avoid
3922 creating a possibly empty if-stmt. */
3923 if (!initp && TYPE_HAS_TRIVIAL_DESTRUCTOR (TREE_TYPE (decl)))
3924 {
3925 node = TREE_CHAIN (node);
3926 continue;
3927 }
3928
3929 /* Remember that we had an initialization or finalization at this
3930 priority. */
3931 priority = DECL_EFFECTIVE_INIT_PRIORITY (decl);
3932 pi = get_priority_info (priority);
3933 if (initp)
3934 pi->initializations_p = 1;
3935 else
3936 pi->destructions_p = 1;
3937
3938 /* Conditionalize this initialization on being in the right priority
3939 and being initializing/finalizing appropriately. */
3940 priority_if_stmt = begin_if_stmt ();
3941 cond = cp_build_binary_op (input_location,
3942 EQ_EXPR,
3943 priority_decl,
3944 build_int_cst (NULL_TREE, priority),
3945 tf_warning_or_error);
3946 finish_if_stmt_cond (cond, priority_if_stmt);
3947
3948 /* Process initializers with same priority. */
3949 for (; node
3950 && DECL_EFFECTIVE_INIT_PRIORITY (TREE_VALUE (node)) == priority;
3951 node = TREE_CHAIN (node))
3952 /* Do one initialization or destruction. */
3953 one_static_initialization_or_destruction (TREE_VALUE (node),
3954 TREE_PURPOSE (node), initp);
3955
3956 /* Finish up the priority if-stmt body. */
3957 finish_then_clause (priority_if_stmt);
3958 finish_if_stmt (priority_if_stmt);
3959
3960 } while (node);
3961
3962 /* Revert what __asan_before_dynamic_init did by calling
3963 __asan_after_dynamic_init. */
3964 if (initp && (flag_sanitize & SANITIZE_ADDRESS))
3965 finish_expr_stmt (asan_dynamic_init_call (/*after_p=*/true));
3966
3967 /* Finish up the init/destruct if-stmt body. */
3968 finish_then_clause (init_if_stmt);
3969 finish_if_stmt (init_if_stmt);
3970 }
3971
3972 /* VARS is a list of variables with static storage duration which may
3973 need initialization and/or finalization. Remove those variables
3974 that don't really need to be initialized or finalized, and return
3975 the resulting list. The order in which the variables appear in
3976 VARS is in reverse order of the order in which they should actually
3977 be initialized. The list we return is in the unreversed order;
3978 i.e., the first variable should be initialized first. */
3979
3980 static tree
prune_vars_needing_no_initialization(tree * vars)3981 prune_vars_needing_no_initialization (tree *vars)
3982 {
3983 tree *var = vars;
3984 tree result = NULL_TREE;
3985
3986 while (*var)
3987 {
3988 tree t = *var;
3989 tree decl = TREE_VALUE (t);
3990 tree init = TREE_PURPOSE (t);
3991
3992 /* Deal gracefully with error. */
3993 if (error_operand_p (decl))
3994 {
3995 var = &TREE_CHAIN (t);
3996 continue;
3997 }
3998
3999 /* The only things that can be initialized are variables. */
4000 gcc_assert (VAR_P (decl));
4001
4002 /* If this object is not defined, we don't need to do anything
4003 here. */
4004 if (DECL_EXTERNAL (decl))
4005 {
4006 var = &TREE_CHAIN (t);
4007 continue;
4008 }
4009
4010 /* Also, if the initializer already contains errors, we can bail
4011 out now. */
4012 if (init && TREE_CODE (init) == TREE_LIST
4013 && value_member (error_mark_node, init))
4014 {
4015 var = &TREE_CHAIN (t);
4016 continue;
4017 }
4018
4019 /* This variable is going to need initialization and/or
4020 finalization, so we add it to the list. */
4021 *var = TREE_CHAIN (t);
4022 TREE_CHAIN (t) = result;
4023 result = t;
4024 }
4025
4026 return result;
4027 }
4028
4029 /* Make sure we have told the back end about all the variables in
4030 VARS. */
4031
4032 static void
write_out_vars(tree vars)4033 write_out_vars (tree vars)
4034 {
4035 tree v;
4036
4037 for (v = vars; v; v = TREE_CHAIN (v))
4038 {
4039 tree var = TREE_VALUE (v);
4040 if (!var_finalized_p (var))
4041 {
4042 import_export_decl (var);
4043 rest_of_decl_compilation (var, 1, 1);
4044 }
4045 }
4046 }
4047
4048 /* Generate a static constructor (if CONSTRUCTOR_P) or destructor
4049 (otherwise) that will initialize all global objects with static
4050 storage duration having the indicated PRIORITY. */
4051
4052 static void
generate_ctor_or_dtor_function(bool constructor_p,int priority,location_t * locus)4053 generate_ctor_or_dtor_function (bool constructor_p, int priority,
4054 location_t *locus)
4055 {
4056 char function_key;
4057 tree fndecl;
4058 tree body;
4059 size_t i;
4060
4061 input_location = *locus;
4062 /* ??? */
4063 /* Was: locus->line++; */
4064
4065 /* We use `I' to indicate initialization and `D' to indicate
4066 destruction. */
4067 function_key = constructor_p ? 'I' : 'D';
4068
4069 /* We emit the function lazily, to avoid generating empty
4070 global constructors and destructors. */
4071 body = NULL_TREE;
4072
4073 /* For Objective-C++, we may need to initialize metadata found in this module.
4074 This must be done _before_ any other static initializations. */
4075 if (c_dialect_objc () && (priority == DEFAULT_INIT_PRIORITY)
4076 && constructor_p && objc_static_init_needed_p ())
4077 {
4078 body = start_objects (function_key, priority);
4079 objc_generate_static_init_call (NULL_TREE);
4080 }
4081
4082 /* Call the static storage duration function with appropriate
4083 arguments. */
4084 FOR_EACH_VEC_SAFE_ELT (ssdf_decls, i, fndecl)
4085 {
4086 /* Calls to pure or const functions will expand to nothing. */
4087 if (! (flags_from_decl_or_type (fndecl) & (ECF_CONST | ECF_PURE)))
4088 {
4089 tree call;
4090
4091 if (! body)
4092 body = start_objects (function_key, priority);
4093
4094 call = cp_build_function_call_nary (fndecl, tf_warning_or_error,
4095 build_int_cst (NULL_TREE,
4096 constructor_p),
4097 build_int_cst (NULL_TREE,
4098 priority),
4099 NULL_TREE);
4100 finish_expr_stmt (call);
4101 }
4102 }
4103
4104 /* Close out the function. */
4105 if (body)
4106 finish_objects (function_key, priority, body);
4107 }
4108
4109 /* Generate constructor and destructor functions for the priority
4110 indicated by N. */
4111
4112 static int
generate_ctor_and_dtor_functions_for_priority(splay_tree_node n,void * data)4113 generate_ctor_and_dtor_functions_for_priority (splay_tree_node n, void * data)
4114 {
4115 location_t *locus = (location_t *) data;
4116 int priority = (int) n->key;
4117 priority_info pi = (priority_info) n->value;
4118
4119 /* Generate the functions themselves, but only if they are really
4120 needed. */
4121 if (pi->initializations_p)
4122 generate_ctor_or_dtor_function (/*constructor_p=*/true, priority, locus);
4123 if (pi->destructions_p)
4124 generate_ctor_or_dtor_function (/*constructor_p=*/false, priority, locus);
4125
4126 /* Keep iterating. */
4127 return 0;
4128 }
4129
4130 /* Return C++ property of T, based on given operation OP. */
4131
4132 static int
cpp_check(tree t,cpp_operation op)4133 cpp_check (tree t, cpp_operation op)
4134 {
4135 switch (op)
4136 {
4137 case HAS_DEPENDENT_TEMPLATE_ARGS:
4138 {
4139 tree ti = CLASSTYPE_TEMPLATE_INFO (t);
4140 if (!ti)
4141 return 0;
4142 ++processing_template_decl;
4143 const bool dep = any_dependent_template_arguments_p (TI_ARGS (ti));
4144 --processing_template_decl;
4145 return dep;
4146 }
4147 case IS_ABSTRACT:
4148 return DECL_PURE_VIRTUAL_P (t);
4149 case IS_CONSTRUCTOR:
4150 return DECL_CONSTRUCTOR_P (t);
4151 case IS_DESTRUCTOR:
4152 return DECL_DESTRUCTOR_P (t);
4153 case IS_COPY_CONSTRUCTOR:
4154 return DECL_COPY_CONSTRUCTOR_P (t);
4155 case IS_MOVE_CONSTRUCTOR:
4156 return DECL_MOVE_CONSTRUCTOR_P (t);
4157 case IS_TEMPLATE:
4158 return TREE_CODE (t) == TEMPLATE_DECL;
4159 case IS_TRIVIAL:
4160 return trivial_type_p (t);
4161 default:
4162 return 0;
4163 }
4164 }
4165
4166 /* Collect source file references recursively, starting from NAMESPC. */
4167
4168 static void
collect_source_refs(tree namespc)4169 collect_source_refs (tree namespc)
4170 {
4171 /* Iterate over names in this name space. */
4172 for (tree t = NAMESPACE_LEVEL (namespc)->names; t; t = TREE_CHAIN (t))
4173 if (DECL_IS_BUILTIN (t))
4174 ;
4175 else if (TREE_CODE (t) == NAMESPACE_DECL && !DECL_NAMESPACE_ALIAS (t))
4176 collect_source_refs (t);
4177 else
4178 collect_source_ref (DECL_SOURCE_FILE (t));
4179 }
4180
4181 /* Collect decls relevant to SOURCE_FILE from all namespaces recursively,
4182 starting from NAMESPC. */
4183
4184 static void
collect_ada_namespace(tree namespc,const char * source_file)4185 collect_ada_namespace (tree namespc, const char *source_file)
4186 {
4187 tree decl = NAMESPACE_LEVEL (namespc)->names;
4188
4189 /* Collect decls from this namespace. This will skip
4190 NAMESPACE_DECLs (both aliases and regular, it cannot tell). */
4191 collect_ada_nodes (decl, source_file);
4192
4193 /* Now scan for namespace children, and dump them. */
4194 for (; decl; decl = TREE_CHAIN (decl))
4195 if (TREE_CODE (decl) == NAMESPACE_DECL && !DECL_NAMESPACE_ALIAS (decl))
4196 collect_ada_namespace (decl, source_file);
4197 }
4198
4199 /* Returns true iff there is a definition available for variable or
4200 function DECL. */
4201
4202 bool
decl_defined_p(tree decl)4203 decl_defined_p (tree decl)
4204 {
4205 if (TREE_CODE (decl) == FUNCTION_DECL)
4206 return (DECL_INITIAL (decl) != NULL_TREE
4207 /* A pending instantiation of a friend temploid is defined. */
4208 || (DECL_FRIEND_PSEUDO_TEMPLATE_INSTANTIATION (decl)
4209 && DECL_INITIAL (DECL_TEMPLATE_RESULT
4210 (DECL_TI_TEMPLATE (decl)))));
4211 else
4212 {
4213 gcc_assert (VAR_P (decl));
4214 return !DECL_EXTERNAL (decl);
4215 }
4216 }
4217
4218 /* Nonzero for a VAR_DECL whose value can be used in a constant expression.
4219
4220 [expr.const]
4221
4222 An integral constant-expression can only involve ... const
4223 variables of integral or enumeration types initialized with
4224 constant expressions ...
4225
4226 C++0x also allows constexpr variables and temporaries initialized
4227 with constant expressions. We handle the former here, but the latter
4228 are just folded away in cxx_eval_constant_expression.
4229
4230 The standard does not require that the expression be non-volatile.
4231 G++ implements the proposed correction in DR 457. */
4232
4233 bool
decl_constant_var_p(tree decl)4234 decl_constant_var_p (tree decl)
4235 {
4236 if (!decl_maybe_constant_var_p (decl))
4237 return false;
4238
4239 /* We don't know if a template static data member is initialized with
4240 a constant expression until we instantiate its initializer. Even
4241 in the case of a constexpr variable, we can't treat it as a
4242 constant until its initializer is complete in case it's used in
4243 its own initializer. */
4244 maybe_instantiate_decl (decl);
4245 return DECL_INITIALIZED_BY_CONSTANT_EXPRESSION_P (decl);
4246 }
4247
4248 /* Returns true if DECL could be a symbolic constant variable, depending on
4249 its initializer. */
4250
4251 bool
decl_maybe_constant_var_p(tree decl)4252 decl_maybe_constant_var_p (tree decl)
4253 {
4254 tree type = TREE_TYPE (decl);
4255 if (!VAR_P (decl))
4256 return false;
4257 if (DECL_DECLARED_CONSTEXPR_P (decl))
4258 return true;
4259 if (DECL_HAS_VALUE_EXPR_P (decl))
4260 /* A proxy isn't constant. */
4261 return false;
4262 if (TREE_CODE (type) == REFERENCE_TYPE)
4263 /* References can be constant. */;
4264 else if (CP_TYPE_CONST_NON_VOLATILE_P (type)
4265 && INTEGRAL_OR_ENUMERATION_TYPE_P (type))
4266 /* And const integers. */;
4267 else
4268 return false;
4269
4270 if (DECL_INITIAL (decl)
4271 && !DECL_INITIALIZED_BY_CONSTANT_EXPRESSION_P (decl))
4272 /* We know the initializer, and it isn't constant. */
4273 return false;
4274 else
4275 return true;
4276 }
4277
4278 /* Complain that DECL uses a type with no linkage. In C++98 mode this is
4279 called from grokfndecl and grokvardecl; in all modes it is called from
4280 cp_write_global_declarations. */
4281
4282 void
no_linkage_error(tree decl)4283 no_linkage_error (tree decl)
4284 {
4285 if (cxx_dialect >= cxx11 && decl_defined_p (decl))
4286 /* In C++11 it's ok if the decl is defined. */
4287 return;
4288 tree t = no_linkage_check (TREE_TYPE (decl), /*relaxed_p=*/false);
4289 if (t == NULL_TREE)
4290 /* The type that got us on no_linkage_decls must have gotten a name for
4291 linkage purposes. */;
4292 else if (CLASS_TYPE_P (t) && TYPE_BEING_DEFINED (t))
4293 /* The type might end up having a typedef name for linkage purposes. */
4294 vec_safe_push (no_linkage_decls, decl);
4295 else if (TYPE_UNNAMED_P (t))
4296 {
4297 bool d = false;
4298 if (cxx_dialect >= cxx11)
4299 d = permerror (DECL_SOURCE_LOCATION (decl), "%q#D, declared using "
4300 "unnamed type, is used but never defined", decl);
4301 else if (DECL_EXTERN_C_P (decl))
4302 /* Allow this; it's pretty common in C. */;
4303 else if (VAR_P (decl))
4304 /* DRs 132, 319 and 389 seem to indicate types with
4305 no linkage can only be used to declare extern "C"
4306 entities. Since it's not always an error in the
4307 ISO C++ 90 Standard, we only issue a warning. */
4308 d = warning_at (DECL_SOURCE_LOCATION (decl), 0, "unnamed type "
4309 "with no linkage used to declare variable %q#D with "
4310 "linkage", decl);
4311 else
4312 d = permerror (DECL_SOURCE_LOCATION (decl), "unnamed type with no "
4313 "linkage used to declare function %q#D with linkage",
4314 decl);
4315 if (d && is_typedef_decl (TYPE_NAME (t)))
4316 inform (DECL_SOURCE_LOCATION (TYPE_NAME (t)), "%q#D does not refer "
4317 "to the unqualified type, so it is not used for linkage",
4318 TYPE_NAME (t));
4319 }
4320 else if (cxx_dialect >= cxx11)
4321 {
4322 if (VAR_P (decl) || !DECL_PURE_VIRTUAL_P (decl))
4323 permerror (DECL_SOURCE_LOCATION (decl),
4324 "%q#D, declared using local type "
4325 "%qT, is used but never defined", decl, t);
4326 }
4327 else if (VAR_P (decl))
4328 warning_at (DECL_SOURCE_LOCATION (decl), 0, "type %qT with no linkage "
4329 "used to declare variable %q#D with linkage", t, decl);
4330 else
4331 permerror (DECL_SOURCE_LOCATION (decl), "type %qT with no linkage used "
4332 "to declare function %q#D with linkage", t, decl);
4333 }
4334
4335 /* Collect declarations from all namespaces relevant to SOURCE_FILE. */
4336
4337 static void
collect_all_refs(const char * source_file)4338 collect_all_refs (const char *source_file)
4339 {
4340 collect_ada_namespace (global_namespace, source_file);
4341 }
4342
4343 /* Clear DECL_EXTERNAL for NODE. */
4344
4345 static bool
clear_decl_external(struct cgraph_node * node,void *)4346 clear_decl_external (struct cgraph_node *node, void * /*data*/)
4347 {
4348 DECL_EXTERNAL (node->decl) = 0;
4349 return false;
4350 }
4351
4352 /* Build up the function to run dynamic initializers for thread_local
4353 variables in this translation unit and alias the init functions for the
4354 individual variables to it. */
4355
4356 static void
handle_tls_init(void)4357 handle_tls_init (void)
4358 {
4359 tree vars = prune_vars_needing_no_initialization (&tls_aggregates);
4360 if (vars == NULL_TREE)
4361 return;
4362
4363 location_t loc = DECL_SOURCE_LOCATION (TREE_VALUE (vars));
4364
4365 write_out_vars (vars);
4366
4367 tree guard = build_decl (loc, VAR_DECL, get_identifier ("__tls_guard"),
4368 boolean_type_node);
4369 TREE_PUBLIC (guard) = false;
4370 TREE_STATIC (guard) = true;
4371 DECL_ARTIFICIAL (guard) = true;
4372 DECL_IGNORED_P (guard) = true;
4373 TREE_USED (guard) = true;
4374 CP_DECL_THREAD_LOCAL_P (guard) = true;
4375 set_decl_tls_model (guard, decl_default_tls_model (guard));
4376 pushdecl_top_level_and_finish (guard, NULL_TREE);
4377
4378 tree fn = get_local_tls_init_fn ();
4379 start_preparsed_function (fn, NULL_TREE, SF_PRE_PARSED);
4380 tree body = begin_function_body ();
4381 tree if_stmt = begin_if_stmt ();
4382 tree cond = cp_build_unary_op (TRUTH_NOT_EXPR, guard, false,
4383 tf_warning_or_error);
4384 finish_if_stmt_cond (cond, if_stmt);
4385 finish_expr_stmt (cp_build_modify_expr (loc, guard, NOP_EXPR,
4386 boolean_true_node,
4387 tf_warning_or_error));
4388 for (; vars; vars = TREE_CHAIN (vars))
4389 {
4390 tree var = TREE_VALUE (vars);
4391 tree init = TREE_PURPOSE (vars);
4392 one_static_initialization_or_destruction (var, init, true);
4393
4394 /* Output init aliases even with -fno-extern-tls-init. */
4395 if (TARGET_SUPPORTS_ALIASES && TREE_PUBLIC (var))
4396 {
4397 tree single_init_fn = get_tls_init_fn (var);
4398 if (single_init_fn == NULL_TREE)
4399 continue;
4400 cgraph_node *alias
4401 = cgraph_node::get_create (fn)->create_same_body_alias
4402 (single_init_fn, fn);
4403 gcc_assert (alias != NULL);
4404 }
4405 }
4406
4407 finish_then_clause (if_stmt);
4408 finish_if_stmt (if_stmt);
4409 finish_function_body (body);
4410 expand_or_defer_fn (finish_function (/*inline_p=*/false));
4411 }
4412
4413 /* We're at the end of compilation, so generate any mangling aliases that
4414 we've been saving up, if DECL is going to be output and ID2 isn't
4415 already taken by another declaration. */
4416
4417 static void
generate_mangling_alias(tree decl,tree id2)4418 generate_mangling_alias (tree decl, tree id2)
4419 {
4420 struct cgraph_node *n = NULL;
4421
4422 if (TREE_CODE (decl) == FUNCTION_DECL)
4423 {
4424 n = cgraph_node::get (decl);
4425 if (!n)
4426 /* Don't create an alias to an unreferenced function. */
4427 return;
4428 }
4429
4430 tree *slot
4431 = mangled_decls->find_slot_with_hash (id2, IDENTIFIER_HASH_VALUE (id2),
4432 INSERT);
4433
4434 /* If there's a declaration already using this mangled name,
4435 don't create a compatibility alias that conflicts. */
4436 if (*slot)
4437 return;
4438
4439 tree alias = make_alias_for (decl, id2);
4440 *slot = alias;
4441
4442 DECL_IGNORED_P (alias) = 1;
4443 TREE_PUBLIC (alias) = TREE_PUBLIC (decl);
4444 DECL_VISIBILITY (alias) = DECL_VISIBILITY (decl);
4445 if (vague_linkage_p (decl))
4446 DECL_WEAK (alias) = 1;
4447
4448 if (n)
4449 n->create_same_body_alias (alias, decl);
4450 else
4451 varpool_node::create_extra_name_alias (alias, decl);
4452 }
4453
4454 /* Note that we might want to emit an alias with the symbol ID2 for DECL at
4455 the end of translation, for compatibility across bugs in the mangling
4456 implementation. */
4457
4458 void
note_mangling_alias(tree decl,tree id2)4459 note_mangling_alias (tree decl, tree id2)
4460 {
4461 if (TARGET_SUPPORTS_ALIASES)
4462 {
4463 if (!defer_mangling_aliases)
4464 generate_mangling_alias (decl, id2);
4465 else
4466 {
4467 vec_safe_push (mangling_aliases, decl);
4468 vec_safe_push (mangling_aliases, id2);
4469 }
4470 }
4471 }
4472
4473 /* Emit all mangling aliases that were deferred up to this point. */
4474
4475 void
generate_mangling_aliases()4476 generate_mangling_aliases ()
4477 {
4478 while (!vec_safe_is_empty (mangling_aliases))
4479 {
4480 tree id2 = mangling_aliases->pop();
4481 tree decl = mangling_aliases->pop();
4482 generate_mangling_alias (decl, id2);
4483 }
4484 defer_mangling_aliases = false;
4485 }
4486
4487 /* Record a mangling of DECL, whose DECL_ASSEMBLER_NAME has just been
4488 set. NEED_WARNING is true if we must warn about collisions. We do
4489 this to spot changes in mangling that may require compatibility
4490 aliases. */
4491
4492 void
record_mangling(tree decl,bool need_warning)4493 record_mangling (tree decl, bool need_warning)
4494 {
4495 if (!mangled_decls)
4496 mangled_decls = hash_table<mangled_decl_hash>::create_ggc (499);
4497
4498 gcc_checking_assert (DECL_ASSEMBLER_NAME_SET_P (decl));
4499 tree id = DECL_ASSEMBLER_NAME_RAW (decl);
4500 tree *slot
4501 = mangled_decls->find_slot_with_hash (id, IDENTIFIER_HASH_VALUE (id),
4502 INSERT);
4503
4504 /* If this is already an alias, remove the alias, because the real
4505 decl takes precedence. */
4506 if (*slot && DECL_ARTIFICIAL (*slot) && DECL_IGNORED_P (*slot))
4507 if (symtab_node *n = symtab_node::get (*slot))
4508 if (n->cpp_implicit_alias)
4509 {
4510 n->remove ();
4511 *slot = NULL_TREE;
4512 }
4513
4514 if (!*slot)
4515 *slot = decl;
4516 else if (need_warning)
4517 {
4518 error_at (DECL_SOURCE_LOCATION (decl),
4519 "mangling of %q#D as %qE conflicts with a previous mangle",
4520 decl, id);
4521 inform (DECL_SOURCE_LOCATION (*slot),
4522 "previous mangling %q#D", *slot);
4523 inform (DECL_SOURCE_LOCATION (decl),
4524 "a later -fabi-version= (or =0)"
4525 " avoids this error with a change in mangling");
4526 *slot = decl;
4527 }
4528 }
4529
4530 /* The mangled name of DECL is being forcibly changed to NAME. Remove
4531 any existing knowledge of DECL's mangled name meaning DECL. */
4532
4533 void
overwrite_mangling(tree decl,tree name)4534 overwrite_mangling (tree decl, tree name)
4535 {
4536 if (tree id = DECL_ASSEMBLER_NAME_RAW (decl))
4537 if ((TREE_CODE (decl) == VAR_DECL
4538 || TREE_CODE (decl) == FUNCTION_DECL)
4539 && mangled_decls)
4540 if (tree *slot
4541 = mangled_decls->find_slot_with_hash (id, IDENTIFIER_HASH_VALUE (id),
4542 NO_INSERT))
4543 if (*slot == decl)
4544 {
4545 mangled_decls->clear_slot (slot);
4546
4547 /* If this is an alias, remove it from the symbol table. */
4548 if (DECL_ARTIFICIAL (decl) && DECL_IGNORED_P (decl))
4549 if (symtab_node *n = symtab_node::get (decl))
4550 if (n->cpp_implicit_alias)
4551 n->remove ();
4552 }
4553
4554 DECL_ASSEMBLER_NAME_RAW (decl) = name;
4555 }
4556
4557 /* The entire file is now complete. If requested, dump everything
4558 to a file. */
4559
4560 static void
dump_tu(void)4561 dump_tu (void)
4562 {
4563 dump_flags_t flags;
4564 if (FILE *stream = dump_begin (raw_dump_id, &flags))
4565 {
4566 dump_node (global_namespace, flags & ~TDF_SLIM, stream);
4567 dump_end (raw_dump_id, stream);
4568 }
4569 }
4570
4571 static location_t locus_at_end_of_parsing;
4572
4573 /* Check the deallocation functions for CODE to see if we want to warn that
4574 only one was defined. */
4575
4576 static void
maybe_warn_sized_delete(enum tree_code code)4577 maybe_warn_sized_delete (enum tree_code code)
4578 {
4579 tree sized = NULL_TREE;
4580 tree unsized = NULL_TREE;
4581
4582 for (ovl_iterator iter (get_global_binding (ovl_op_identifier (false, code)));
4583 iter; ++iter)
4584 {
4585 tree fn = *iter;
4586 /* We're only interested in usual deallocation functions. */
4587 if (!usual_deallocation_fn_p (fn))
4588 continue;
4589 if (FUNCTION_ARG_CHAIN (fn) == void_list_node)
4590 unsized = fn;
4591 else
4592 sized = fn;
4593 }
4594 if (DECL_INITIAL (unsized) && !DECL_INITIAL (sized))
4595 warning_at (DECL_SOURCE_LOCATION (unsized), OPT_Wsized_deallocation,
4596 "the program should also define %qD", sized);
4597 else if (!DECL_INITIAL (unsized) && DECL_INITIAL (sized))
4598 warning_at (DECL_SOURCE_LOCATION (sized), OPT_Wsized_deallocation,
4599 "the program should also define %qD", unsized);
4600 }
4601
4602 /* Check the global deallocation functions to see if we want to warn about
4603 defining unsized without sized (or vice versa). */
4604
4605 static void
maybe_warn_sized_delete()4606 maybe_warn_sized_delete ()
4607 {
4608 if (!flag_sized_deallocation || !warn_sized_deallocation)
4609 return;
4610 maybe_warn_sized_delete (DELETE_EXPR);
4611 maybe_warn_sized_delete (VEC_DELETE_EXPR);
4612 }
4613
4614 /* Earlier we left PTRMEM_CST in variable initializers alone so that we could
4615 look them up when evaluating non-type template parameters. Now we need to
4616 lower them to something the back end can understand. */
4617
4618 static void
lower_var_init()4619 lower_var_init ()
4620 {
4621 varpool_node *node;
4622 FOR_EACH_VARIABLE (node)
4623 {
4624 tree d = node->decl;
4625 if (tree init = DECL_INITIAL (d))
4626 DECL_INITIAL (d) = cplus_expand_constant (init);
4627 }
4628 }
4629
4630 /* This routine is called at the end of compilation.
4631 Its job is to create all the code needed to initialize and
4632 destroy the global aggregates. We do the destruction
4633 first, since that way we only need to reverse the decls once. */
4634
4635 void
c_parse_final_cleanups(void)4636 c_parse_final_cleanups (void)
4637 {
4638 tree vars;
4639 bool reconsider;
4640 size_t i;
4641 unsigned ssdf_count = 0;
4642 int retries = 0;
4643 tree decl;
4644
4645 locus_at_end_of_parsing = input_location;
4646 at_eof = 1;
4647
4648 /* Bad parse errors. Just forget about it. */
4649 if (! global_bindings_p () || current_class_type
4650 || !vec_safe_is_empty (decl_namespace_list))
4651 return;
4652
4653 /* This is the point to write out a PCH if we're doing that.
4654 In that case we do not want to do anything else. */
4655 if (pch_file)
4656 {
4657 /* Mangle all symbols at PCH creation time. */
4658 symtab_node *node;
4659 FOR_EACH_SYMBOL (node)
4660 if (! is_a <varpool_node *> (node)
4661 || ! DECL_HARD_REGISTER (node->decl))
4662 DECL_ASSEMBLER_NAME (node->decl);
4663 c_common_write_pch ();
4664 dump_tu ();
4665 /* Ensure even the callers don't try to finalize the CU. */
4666 flag_syntax_only = 1;
4667 return;
4668 }
4669
4670 timevar_stop (TV_PHASE_PARSING);
4671 timevar_start (TV_PHASE_DEFERRED);
4672
4673 symtab->process_same_body_aliases ();
4674
4675 /* Handle -fdump-ada-spec[-slim] */
4676 if (flag_dump_ada_spec || flag_dump_ada_spec_slim)
4677 {
4678 if (flag_dump_ada_spec_slim)
4679 collect_source_ref (main_input_filename);
4680 else
4681 collect_source_refs (global_namespace);
4682
4683 dump_ada_specs (collect_all_refs, cpp_check);
4684 }
4685
4686 /* FIXME - huh? was input_line -= 1;*/
4687
4688 /* We now have to write out all the stuff we put off writing out.
4689 These include:
4690
4691 o Template specializations that we have not yet instantiated,
4692 but which are needed.
4693 o Initialization and destruction for non-local objects with
4694 static storage duration. (Local objects with static storage
4695 duration are initialized when their scope is first entered,
4696 and are cleaned up via atexit.)
4697 o Virtual function tables.
4698
4699 All of these may cause others to be needed. For example,
4700 instantiating one function may cause another to be needed, and
4701 generating the initializer for an object may cause templates to be
4702 instantiated, etc., etc. */
4703
4704 emit_support_tinfos ();
4705
4706 do
4707 {
4708 tree t;
4709 tree decl;
4710
4711 reconsider = false;
4712
4713 /* If there are templates that we've put off instantiating, do
4714 them now. */
4715 instantiate_pending_templates (retries);
4716 ggc_collect ();
4717
4718 /* Write out virtual tables as required. Writing out the
4719 virtual table for a template class may cause the
4720 instantiation of members of that class. If we write out
4721 vtables then we remove the class from our list so we don't
4722 have to look at it again. */
4723 for (i = keyed_classes->length ();
4724 keyed_classes->iterate (--i, &t);)
4725 if (maybe_emit_vtables (t))
4726 {
4727 reconsider = true;
4728 keyed_classes->unordered_remove (i);
4729 }
4730 /* The input_location may have been changed during marking of
4731 vtable entries. */
4732 input_location = locus_at_end_of_parsing;
4733
4734 /* Write out needed type info variables. We have to be careful
4735 looping through unemitted decls, because emit_tinfo_decl may
4736 cause other variables to be needed. New elements will be
4737 appended, and we remove from the vector those that actually
4738 get emitted. */
4739 for (i = unemitted_tinfo_decls->length ();
4740 unemitted_tinfo_decls->iterate (--i, &t);)
4741 if (emit_tinfo_decl (t))
4742 {
4743 reconsider = true;
4744 unemitted_tinfo_decls->unordered_remove (i);
4745 }
4746
4747 /* The list of objects with static storage duration is built up
4748 in reverse order. We clear STATIC_AGGREGATES so that any new
4749 aggregates added during the initialization of these will be
4750 initialized in the correct order when we next come around the
4751 loop. */
4752 vars = prune_vars_needing_no_initialization (&static_aggregates);
4753
4754 if (vars)
4755 {
4756 /* We need to start a new initialization function each time
4757 through the loop. That's because we need to know which
4758 vtables have been referenced, and TREE_SYMBOL_REFERENCED
4759 isn't computed until a function is finished, and written
4760 out. That's a deficiency in the back end. When this is
4761 fixed, these initialization functions could all become
4762 inline, with resulting performance improvements. */
4763 tree ssdf_body;
4764
4765 /* Set the line and file, so that it is obviously not from
4766 the source file. */
4767 input_location = locus_at_end_of_parsing;
4768 ssdf_body = start_static_storage_duration_function (ssdf_count);
4769
4770 /* Make sure the back end knows about all the variables. */
4771 write_out_vars (vars);
4772
4773 /* First generate code to do all the initializations. */
4774 if (vars)
4775 do_static_initialization_or_destruction (vars, /*initp=*/true);
4776
4777 /* Then, generate code to do all the destructions. Do these
4778 in reverse order so that the most recently constructed
4779 variable is the first destroyed. If we're using
4780 __cxa_atexit, then we don't need to do this; functions
4781 were registered at initialization time to destroy the
4782 local statics. */
4783 if (!flag_use_cxa_atexit && vars)
4784 {
4785 vars = nreverse (vars);
4786 do_static_initialization_or_destruction (vars, /*initp=*/false);
4787 }
4788 else
4789 vars = NULL_TREE;
4790
4791 /* Finish up the static storage duration function for this
4792 round. */
4793 input_location = locus_at_end_of_parsing;
4794 finish_static_storage_duration_function (ssdf_body);
4795
4796 /* All those initializations and finalizations might cause
4797 us to need more inline functions, more template
4798 instantiations, etc. */
4799 reconsider = true;
4800 ssdf_count++;
4801 /* ??? was: locus_at_end_of_parsing.line++; */
4802 }
4803
4804 /* Now do the same for thread_local variables. */
4805 handle_tls_init ();
4806
4807 /* Go through the set of inline functions whose bodies have not
4808 been emitted yet. If out-of-line copies of these functions
4809 are required, emit them. */
4810 FOR_EACH_VEC_SAFE_ELT (deferred_fns, i, decl)
4811 {
4812 /* Does it need synthesizing? */
4813 if (DECL_DEFAULTED_FN (decl) && ! DECL_INITIAL (decl)
4814 && (! DECL_REALLY_EXTERN (decl) || possibly_inlined_p (decl)))
4815 {
4816 /* Even though we're already at the top-level, we push
4817 there again. That way, when we pop back a few lines
4818 hence, all of our state is restored. Otherwise,
4819 finish_function doesn't clean things up, and we end
4820 up with CURRENT_FUNCTION_DECL set. */
4821 push_to_top_level ();
4822 /* The decl's location will mark where it was first
4823 needed. Save that so synthesize method can indicate
4824 where it was needed from, in case of error */
4825 input_location = DECL_SOURCE_LOCATION (decl);
4826 synthesize_method (decl);
4827 pop_from_top_level ();
4828 reconsider = true;
4829 }
4830
4831 if (!DECL_INITIAL (decl) && decl_tls_wrapper_p (decl))
4832 generate_tls_wrapper (decl);
4833
4834 if (!DECL_SAVED_TREE (decl))
4835 continue;
4836
4837 cgraph_node *node = cgraph_node::get_create (decl);
4838
4839 /* We lie to the back end, pretending that some functions
4840 are not defined when they really are. This keeps these
4841 functions from being put out unnecessarily. But, we must
4842 stop lying when the functions are referenced, or if they
4843 are not comdat since they need to be put out now. If
4844 DECL_INTERFACE_KNOWN, then we have already set
4845 DECL_EXTERNAL appropriately, so there's no need to check
4846 again, and we do not want to clear DECL_EXTERNAL if a
4847 previous call to import_export_decl set it.
4848
4849 This is done in a separate for cycle, because if some
4850 deferred function is contained in another deferred
4851 function later in deferred_fns varray,
4852 rest_of_compilation would skip this function and we
4853 really cannot expand the same function twice. */
4854 import_export_decl (decl);
4855 if (DECL_NOT_REALLY_EXTERN (decl)
4856 && DECL_INITIAL (decl)
4857 && decl_needed_p (decl))
4858 {
4859 if (node->cpp_implicit_alias)
4860 node = node->get_alias_target ();
4861
4862 node->call_for_symbol_thunks_and_aliases (clear_decl_external,
4863 NULL, true);
4864 /* If we mark !DECL_EXTERNAL one of the symbols in some comdat
4865 group, we need to mark all symbols in the same comdat group
4866 that way. */
4867 if (node->same_comdat_group)
4868 for (cgraph_node *next
4869 = dyn_cast<cgraph_node *> (node->same_comdat_group);
4870 next != node;
4871 next = dyn_cast<cgraph_node *> (next->same_comdat_group))
4872 next->call_for_symbol_thunks_and_aliases (clear_decl_external,
4873 NULL, true);
4874 }
4875
4876 /* If we're going to need to write this function out, and
4877 there's already a body for it, create RTL for it now.
4878 (There might be no body if this is a method we haven't
4879 gotten around to synthesizing yet.) */
4880 if (!DECL_EXTERNAL (decl)
4881 && decl_needed_p (decl)
4882 && !TREE_ASM_WRITTEN (decl)
4883 && !node->definition)
4884 {
4885 /* We will output the function; no longer consider it in this
4886 loop. */
4887 DECL_DEFER_OUTPUT (decl) = 0;
4888 /* Generate RTL for this function now that we know we
4889 need it. */
4890 expand_or_defer_fn (decl);
4891 /* If we're compiling -fsyntax-only pretend that this
4892 function has been written out so that we don't try to
4893 expand it again. */
4894 if (flag_syntax_only)
4895 TREE_ASM_WRITTEN (decl) = 1;
4896 reconsider = true;
4897 }
4898 }
4899
4900 if (wrapup_namespace_globals ())
4901 reconsider = true;
4902
4903 /* Static data members are just like namespace-scope globals. */
4904 FOR_EACH_VEC_SAFE_ELT (pending_statics, i, decl)
4905 {
4906 if (var_finalized_p (decl) || DECL_REALLY_EXTERN (decl)
4907 /* Don't write it out if we haven't seen a definition. */
4908 || (DECL_IN_AGGR_P (decl) && !DECL_INLINE_VAR_P (decl))
4909 /* Or haven't instantiated it. */
4910 || (DECL_TEMPLATE_INSTANTIATION (decl)
4911 && !DECL_TEMPLATE_INSTANTIATED (decl)))
4912 continue;
4913 import_export_decl (decl);
4914 /* If this static data member is needed, provide it to the
4915 back end. */
4916 if (DECL_NOT_REALLY_EXTERN (decl) && decl_needed_p (decl))
4917 DECL_EXTERNAL (decl) = 0;
4918 }
4919 if (vec_safe_length (pending_statics) != 0
4920 && wrapup_global_declarations (pending_statics->address (),
4921 pending_statics->length ()))
4922 reconsider = true;
4923
4924 retries++;
4925 }
4926 while (reconsider);
4927
4928 lower_var_init ();
4929
4930 generate_mangling_aliases ();
4931
4932 /* All used inline functions must have a definition at this point. */
4933 FOR_EACH_VEC_SAFE_ELT (deferred_fns, i, decl)
4934 {
4935 if (/* Check online inline functions that were actually used. */
4936 DECL_ODR_USED (decl) && DECL_DECLARED_INLINE_P (decl)
4937 /* If the definition actually was available here, then the
4938 fact that the function was not defined merely represents
4939 that for some reason (use of a template repository,
4940 #pragma interface, etc.) we decided not to emit the
4941 definition here. */
4942 && !DECL_INITIAL (decl)
4943 /* Don't complain if the template was defined. */
4944 && !(DECL_TEMPLATE_INSTANTIATION (decl)
4945 && DECL_INITIAL (DECL_TEMPLATE_RESULT
4946 (template_for_substitution (decl)))))
4947 {
4948 warning_at (DECL_SOURCE_LOCATION (decl), 0,
4949 "inline function %qD used but never defined", decl);
4950 /* Avoid a duplicate warning from check_global_declaration. */
4951 TREE_NO_WARNING (decl) = 1;
4952 }
4953 }
4954
4955 /* So must decls that use a type with no linkage. */
4956 FOR_EACH_VEC_SAFE_ELT (no_linkage_decls, i, decl)
4957 no_linkage_error (decl);
4958
4959 maybe_warn_sized_delete ();
4960
4961 /* Then, do the Objective-C stuff. This is where all the
4962 Objective-C module stuff gets generated (symtab,
4963 class/protocol/selector lists etc). This must be done after C++
4964 templates, destructors etc. so that selectors used in C++
4965 templates are properly allocated. */
4966 if (c_dialect_objc ())
4967 objc_write_global_declarations ();
4968
4969 /* We give C linkage to static constructors and destructors. */
4970 push_lang_context (lang_name_c);
4971
4972 /* Generate initialization and destruction functions for all
4973 priorities for which they are required. */
4974 if (priority_info_map)
4975 splay_tree_foreach (priority_info_map,
4976 generate_ctor_and_dtor_functions_for_priority,
4977 /*data=*/&locus_at_end_of_parsing);
4978 else if (c_dialect_objc () && objc_static_init_needed_p ())
4979 /* If this is obj-c++ and we need a static init, call
4980 generate_ctor_or_dtor_function. */
4981 generate_ctor_or_dtor_function (/*constructor_p=*/true,
4982 DEFAULT_INIT_PRIORITY,
4983 &locus_at_end_of_parsing);
4984
4985 /* We're done with the splay-tree now. */
4986 if (priority_info_map)
4987 splay_tree_delete (priority_info_map);
4988
4989 /* Generate any missing aliases. */
4990 maybe_apply_pending_pragma_weaks ();
4991
4992 /* We're done with static constructors, so we can go back to "C++"
4993 linkage now. */
4994 pop_lang_context ();
4995
4996 if (flag_vtable_verify)
4997 {
4998 vtv_recover_class_info ();
4999 vtv_compute_class_hierarchy_transitive_closure ();
5000 vtv_build_vtable_verify_fndecl ();
5001 }
5002
5003 perform_deferred_noexcept_checks ();
5004
5005 finish_repo ();
5006 fini_constexpr ();
5007
5008 /* The entire file is now complete. If requested, dump everything
5009 to a file. */
5010 dump_tu ();
5011
5012 if (flag_detailed_statistics)
5013 {
5014 dump_tree_statistics ();
5015 dump_time_statistics ();
5016 }
5017
5018 timevar_stop (TV_PHASE_DEFERRED);
5019 timevar_start (TV_PHASE_PARSING);
5020
5021 /* Indicate that we're done with front end processing. */
5022 at_eof = 2;
5023 }
5024
5025 /* Perform any post compilation-proper cleanups for the C++ front-end.
5026 This should really go away. No front-end should need to do
5027 anything past the compilation process. */
5028
5029 void
cxx_post_compilation_parsing_cleanups(void)5030 cxx_post_compilation_parsing_cleanups (void)
5031 {
5032 timevar_start (TV_PHASE_LATE_PARSING_CLEANUPS);
5033
5034 if (flag_vtable_verify)
5035 {
5036 /* Generate the special constructor initialization function that
5037 calls __VLTRegisterPairs, and give it a very high
5038 initialization priority. This must be done after
5039 finalize_compilation_unit so that we have accurate
5040 information about which vtable will actually be emitted. */
5041 vtv_generate_init_routine ();
5042 }
5043
5044 input_location = locus_at_end_of_parsing;
5045
5046 if (flag_checking)
5047 validate_conversion_obstack ();
5048
5049 timevar_stop (TV_PHASE_LATE_PARSING_CLEANUPS);
5050 }
5051
5052 /* FN is an OFFSET_REF, DOTSTAR_EXPR or MEMBER_REF indicating the
5053 function to call in parse-tree form; it has not yet been
5054 semantically analyzed. ARGS are the arguments to the function.
5055 They have already been semantically analyzed. This may change
5056 ARGS. */
5057
5058 tree
build_offset_ref_call_from_tree(tree fn,vec<tree,va_gc> ** args,tsubst_flags_t complain)5059 build_offset_ref_call_from_tree (tree fn, vec<tree, va_gc> **args,
5060 tsubst_flags_t complain)
5061 {
5062 tree orig_fn;
5063 vec<tree, va_gc> *orig_args = NULL;
5064 tree expr;
5065 tree object;
5066
5067 orig_fn = fn;
5068 object = TREE_OPERAND (fn, 0);
5069
5070 if (processing_template_decl)
5071 {
5072 gcc_assert (TREE_CODE (fn) == DOTSTAR_EXPR
5073 || TREE_CODE (fn) == MEMBER_REF);
5074 if (type_dependent_expression_p (fn)
5075 || any_type_dependent_arguments_p (*args))
5076 return build_min_nt_call_vec (fn, *args);
5077
5078 orig_args = make_tree_vector_copy (*args);
5079
5080 /* Transform the arguments and add the implicit "this"
5081 parameter. That must be done before the FN is transformed
5082 because we depend on the form of FN. */
5083 make_args_non_dependent (*args);
5084 object = build_non_dependent_expr (object);
5085 if (TREE_CODE (TREE_TYPE (fn)) == METHOD_TYPE)
5086 {
5087 if (TREE_CODE (fn) == DOTSTAR_EXPR)
5088 object = cp_build_addr_expr (object, complain);
5089 vec_safe_insert (*args, 0, object);
5090 }
5091 /* Now that the arguments are done, transform FN. */
5092 fn = build_non_dependent_expr (fn);
5093 }
5094
5095 /* A qualified name corresponding to a bound pointer-to-member is
5096 represented as an OFFSET_REF:
5097
5098 struct B { void g(); };
5099 void (B::*p)();
5100 void B::g() { (this->*p)(); } */
5101 if (TREE_CODE (fn) == OFFSET_REF)
5102 {
5103 tree object_addr = cp_build_addr_expr (object, complain);
5104 fn = TREE_OPERAND (fn, 1);
5105 fn = get_member_function_from_ptrfunc (&object_addr, fn,
5106 complain);
5107 vec_safe_insert (*args, 0, object_addr);
5108 }
5109
5110 if (CLASS_TYPE_P (TREE_TYPE (fn)))
5111 expr = build_op_call (fn, args, complain);
5112 else
5113 expr = cp_build_function_call_vec (fn, args, complain);
5114 if (processing_template_decl && expr != error_mark_node)
5115 expr = build_min_non_dep_call_vec (expr, orig_fn, orig_args);
5116
5117 if (orig_args != NULL)
5118 release_tree_vector (orig_args);
5119
5120 return expr;
5121 }
5122
5123
5124 void
check_default_args(tree x)5125 check_default_args (tree x)
5126 {
5127 tree arg = TYPE_ARG_TYPES (TREE_TYPE (x));
5128 bool saw_def = false;
5129 int i = 0 - (TREE_CODE (TREE_TYPE (x)) == METHOD_TYPE);
5130 for (; arg && arg != void_list_node; arg = TREE_CHAIN (arg), ++i)
5131 {
5132 if (TREE_PURPOSE (arg))
5133 saw_def = true;
5134 else if (saw_def && !PACK_EXPANSION_P (TREE_VALUE (arg)))
5135 {
5136 error ("default argument missing for parameter %P of %q+#D", i, x);
5137 TREE_PURPOSE (arg) = error_mark_node;
5138 }
5139 }
5140 }
5141
5142 /* Return true if function DECL can be inlined. This is used to force
5143 instantiation of methods that might be interesting for inlining. */
5144 bool
possibly_inlined_p(tree decl)5145 possibly_inlined_p (tree decl)
5146 {
5147 gcc_assert (TREE_CODE (decl) == FUNCTION_DECL);
5148 if (DECL_UNINLINABLE (decl))
5149 return false;
5150 if (!optimize)
5151 return DECL_DECLARED_INLINE_P (decl);
5152 /* When optimizing, we might inline everything when flatten
5153 attribute or heuristics inlining for size or autoinlining
5154 is used. */
5155 return true;
5156 }
5157
5158 /* Normally, we can wait until instantiation-time to synthesize DECL.
5159 However, if DECL is a static data member initialized with a constant
5160 or a constexpr function, we need it right now because a reference to
5161 such a data member or a call to such function is not value-dependent.
5162 For a function that uses auto in the return type, we need to instantiate
5163 it to find out its type. For OpenMP user defined reductions, we need
5164 them instantiated for reduction clauses which inline them by hand
5165 directly. */
5166
5167 static void
maybe_instantiate_decl(tree decl)5168 maybe_instantiate_decl (tree decl)
5169 {
5170 if (DECL_LANG_SPECIFIC (decl)
5171 && DECL_TEMPLATE_INFO (decl)
5172 && (decl_maybe_constant_var_p (decl)
5173 || (TREE_CODE (decl) == FUNCTION_DECL
5174 && DECL_OMP_DECLARE_REDUCTION_P (decl))
5175 || undeduced_auto_decl (decl))
5176 && !DECL_DECLARED_CONCEPT_P (decl)
5177 && !uses_template_parms (DECL_TI_ARGS (decl)))
5178 {
5179 /* Instantiating a function will result in garbage collection. We
5180 must treat this situation as if we were within the body of a
5181 function so as to avoid collecting live data only referenced from
5182 the stack (such as overload resolution candidates). */
5183 ++function_depth;
5184 instantiate_decl (decl, /*defer_ok=*/false,
5185 /*expl_inst_class_mem_p=*/false);
5186 --function_depth;
5187 }
5188 }
5189
5190 /* Mark DECL (either a _DECL or a BASELINK) as "used" in the program.
5191 If DECL is a specialization or implicitly declared class member,
5192 generate the actual definition. Return false if something goes
5193 wrong, true otherwise. */
5194
5195 bool
mark_used(tree decl,tsubst_flags_t complain)5196 mark_used (tree decl, tsubst_flags_t complain)
5197 {
5198 /* If we're just testing conversions or resolving overloads, we
5199 don't want any permanent effects like forcing functions to be
5200 output or instantiating templates. */
5201 if ((complain & tf_conv))
5202 return true;
5203
5204 /* If DECL is a BASELINK for a single function, then treat it just
5205 like the DECL for the function. Otherwise, if the BASELINK is
5206 for an overloaded function, we don't know which function was
5207 actually used until after overload resolution. */
5208 if (BASELINK_P (decl))
5209 {
5210 decl = BASELINK_FUNCTIONS (decl);
5211 if (really_overloaded_fn (decl))
5212 return true;
5213 decl = OVL_FIRST (decl);
5214 }
5215
5216 /* Set TREE_USED for the benefit of -Wunused. */
5217 TREE_USED (decl) = 1;
5218 /* And for structured bindings also the underlying decl. */
5219 if (DECL_DECOMPOSITION_P (decl) && DECL_DECOMP_BASE (decl))
5220 TREE_USED (DECL_DECOMP_BASE (decl)) = 1;
5221
5222 if (TREE_CODE (decl) == TEMPLATE_DECL)
5223 return true;
5224
5225 if (DECL_CLONED_FUNCTION_P (decl))
5226 TREE_USED (DECL_CLONED_FUNCTION (decl)) = 1;
5227
5228 /* Mark enumeration types as used. */
5229 if (TREE_CODE (decl) == CONST_DECL)
5230 used_types_insert (DECL_CONTEXT (decl));
5231
5232 if (TREE_CODE (decl) == FUNCTION_DECL
5233 && !maybe_instantiate_noexcept (decl, complain))
5234 return false;
5235
5236 if (TREE_CODE (decl) == FUNCTION_DECL
5237 && DECL_DELETED_FN (decl))
5238 {
5239 if (DECL_ARTIFICIAL (decl)
5240 && DECL_CONV_FN_P (decl)
5241 && LAMBDA_TYPE_P (DECL_CONTEXT (decl)))
5242 /* We mark a lambda conversion op as deleted if we can't
5243 generate it properly; see maybe_add_lambda_conv_op. */
5244 sorry ("converting lambda that uses %<...%> to function pointer");
5245 else if (complain & tf_error)
5246 {
5247 error ("use of deleted function %qD", decl);
5248 if (!maybe_explain_implicit_delete (decl))
5249 inform (DECL_SOURCE_LOCATION (decl), "declared here");
5250 }
5251 return false;
5252 }
5253
5254 if (TREE_DEPRECATED (decl) && (complain & tf_warning)
5255 && deprecated_state != DEPRECATED_SUPPRESS)
5256 warn_deprecated_use (decl, NULL_TREE);
5257
5258 /* We can only check DECL_ODR_USED on variables or functions with
5259 DECL_LANG_SPECIFIC set, and these are also the only decls that we
5260 might need special handling for. */
5261 if (!VAR_OR_FUNCTION_DECL_P (decl)
5262 || DECL_LANG_SPECIFIC (decl) == NULL
5263 || DECL_THUNK_P (decl))
5264 {
5265 if (!processing_template_decl
5266 && !require_deduced_type (decl, complain))
5267 return false;
5268 return true;
5269 }
5270
5271 /* We only want to do this processing once. We don't need to keep trying
5272 to instantiate inline templates, because unit-at-a-time will make sure
5273 we get them compiled before functions that want to inline them. */
5274 if (DECL_ODR_USED (decl))
5275 return true;
5276
5277 /* Normally, we can wait until instantiation-time to synthesize DECL.
5278 However, if DECL is a static data member initialized with a constant
5279 or a constexpr function, we need it right now because a reference to
5280 such a data member or a call to such function is not value-dependent.
5281 For a function that uses auto in the return type, we need to instantiate
5282 it to find out its type. For OpenMP user defined reductions, we need
5283 them instantiated for reduction clauses which inline them by hand
5284 directly. */
5285 maybe_instantiate_decl (decl);
5286
5287 if (processing_template_decl || in_template_function ())
5288 return true;
5289
5290 /* Check this too in case we're within instantiate_non_dependent_expr. */
5291 if (DECL_TEMPLATE_INFO (decl)
5292 && uses_template_parms (DECL_TI_ARGS (decl)))
5293 return true;
5294
5295 if (!require_deduced_type (decl, complain))
5296 return false;
5297
5298 if (builtin_pack_fn_p (decl))
5299 {
5300 error ("use of built-in parameter pack %qD outside of a template",
5301 DECL_NAME (decl));
5302 return false;
5303 }
5304
5305 /* If we don't need a value, then we don't need to synthesize DECL. */
5306 if (cp_unevaluated_operand || in_discarded_stmt)
5307 return true;
5308
5309 DECL_ODR_USED (decl) = 1;
5310 if (DECL_CLONED_FUNCTION_P (decl))
5311 DECL_ODR_USED (DECL_CLONED_FUNCTION (decl)) = 1;
5312
5313 /* DR 757: A type without linkage shall not be used as the type of a
5314 variable or function with linkage, unless
5315 o the variable or function has extern "C" linkage (7.5 [dcl.link]), or
5316 o the variable or function is not used (3.2 [basic.def.odr]) or is
5317 defined in the same translation unit. */
5318 if (cxx_dialect > cxx98
5319 && decl_linkage (decl) != lk_none
5320 && !DECL_EXTERN_C_P (decl)
5321 && !DECL_ARTIFICIAL (decl)
5322 && !decl_defined_p (decl)
5323 && no_linkage_check (TREE_TYPE (decl), /*relaxed_p=*/false))
5324 {
5325 if (is_local_extern (decl))
5326 /* There's no way to define a local extern, and adding it to
5327 the vector interferes with GC, so give an error now. */
5328 no_linkage_error (decl);
5329 else
5330 vec_safe_push (no_linkage_decls, decl);
5331 }
5332
5333 if (TREE_CODE (decl) == FUNCTION_DECL && DECL_DECLARED_INLINE_P (decl)
5334 && !DECL_INITIAL (decl) && !DECL_ARTIFICIAL (decl))
5335 /* Remember it, so we can check it was defined. */
5336 note_vague_linkage_fn (decl);
5337
5338 /* Is it a synthesized method that needs to be synthesized? */
5339 if (TREE_CODE (decl) == FUNCTION_DECL
5340 && DECL_NONSTATIC_MEMBER_FUNCTION_P (decl)
5341 && DECL_DEFAULTED_FN (decl)
5342 /* A function defaulted outside the class is synthesized either by
5343 cp_finish_decl or instantiate_decl. */
5344 && !DECL_DEFAULTED_OUTSIDE_CLASS_P (decl)
5345 && ! DECL_INITIAL (decl))
5346 {
5347 /* Defer virtual destructors so that thunks get the right
5348 linkage. */
5349 if (DECL_VIRTUAL_P (decl) && !at_eof)
5350 {
5351 note_vague_linkage_fn (decl);
5352 return true;
5353 }
5354
5355 /* Remember the current location for a function we will end up
5356 synthesizing. Then we can inform the user where it was
5357 required in the case of error. */
5358 DECL_SOURCE_LOCATION (decl) = input_location;
5359
5360 /* Synthesizing an implicitly defined member function will result in
5361 garbage collection. We must treat this situation as if we were
5362 within the body of a function so as to avoid collecting live data
5363 on the stack (such as overload resolution candidates).
5364
5365 We could just let cp_write_global_declarations handle synthesizing
5366 this function by adding it to deferred_fns, but doing
5367 it at the use site produces better error messages. */
5368 ++function_depth;
5369 synthesize_method (decl);
5370 --function_depth;
5371 /* If this is a synthesized method we don't need to
5372 do the instantiation test below. */
5373 }
5374 else if (VAR_OR_FUNCTION_DECL_P (decl)
5375 && DECL_TEMPLATE_INFO (decl)
5376 && !DECL_DECLARED_CONCEPT_P (decl)
5377 && (!DECL_EXPLICIT_INSTANTIATION (decl)
5378 || always_instantiate_p (decl)))
5379 /* If this is a function or variable that is an instance of some
5380 template, we now know that we will need to actually do the
5381 instantiation. We check that DECL is not an explicit
5382 instantiation because that is not checked in instantiate_decl.
5383
5384 We put off instantiating functions in order to improve compile
5385 times. Maintaining a stack of active functions is expensive,
5386 and the inliner knows to instantiate any functions it might
5387 need. Therefore, we always try to defer instantiation. */
5388 {
5389 ++function_depth;
5390 instantiate_decl (decl, /*defer_ok=*/true,
5391 /*expl_inst_class_mem_p=*/false);
5392 --function_depth;
5393 }
5394
5395 return true;
5396 }
5397
5398 bool
mark_used(tree decl)5399 mark_used (tree decl)
5400 {
5401 return mark_used (decl, tf_warning_or_error);
5402 }
5403
5404 tree
vtv_start_verification_constructor_init_function(void)5405 vtv_start_verification_constructor_init_function (void)
5406 {
5407 return start_objects ('I', MAX_RESERVED_INIT_PRIORITY - 1);
5408 }
5409
5410 tree
vtv_finish_verification_constructor_init_function(tree function_body)5411 vtv_finish_verification_constructor_init_function (tree function_body)
5412 {
5413 tree fn;
5414
5415 finish_compound_stmt (function_body);
5416 fn = finish_function (/*inline_p=*/false);
5417 DECL_STATIC_CONSTRUCTOR (fn) = 1;
5418 decl_init_priority_insert (fn, MAX_RESERVED_INIT_PRIORITY - 1);
5419
5420 return fn;
5421 }
5422
5423 #include "gt-cp-decl2.h"
5424