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 /* Adjust the TLS model on variable DECL if need be, typically after
1842 the linkage of DECL has been modified. */
1843
1844 static void
adjust_var_decl_tls_model(tree decl)1845 adjust_var_decl_tls_model (tree decl)
1846 {
1847 if (CP_DECL_THREAD_LOCAL_P (decl)
1848 && !lookup_attribute ("tls_model", DECL_ATTRIBUTES (decl)))
1849 set_decl_tls_model (decl, decl_default_tls_model (decl));
1850 }
1851
1852 /* Set DECL up to have the closest approximation of "initialized common"
1853 linkage available. */
1854
1855 void
comdat_linkage(tree decl)1856 comdat_linkage (tree decl)
1857 {
1858 if (flag_weak)
1859 make_decl_one_only (decl, cxx_comdat_group (decl));
1860 else if (TREE_CODE (decl) == FUNCTION_DECL
1861 || (VAR_P (decl) && DECL_ARTIFICIAL (decl)))
1862 /* We can just emit function and compiler-generated variables
1863 statically; having multiple copies is (for the most part) only
1864 a waste of space.
1865
1866 There are two correctness issues, however: the address of a
1867 template instantiation with external linkage should be the
1868 same, independent of what translation unit asks for the
1869 address, and this will not hold when we emit multiple copies of
1870 the function. However, there's little else we can do.
1871
1872 Also, by default, the typeinfo implementation assumes that
1873 there will be only one copy of the string used as the name for
1874 each type. Therefore, if weak symbols are unavailable, the
1875 run-time library should perform a more conservative check; it
1876 should perform a string comparison, rather than an address
1877 comparison. */
1878 TREE_PUBLIC (decl) = 0;
1879 else
1880 {
1881 /* Static data member template instantiations, however, cannot
1882 have multiple copies. */
1883 if (DECL_INITIAL (decl) == 0
1884 || DECL_INITIAL (decl) == error_mark_node)
1885 DECL_COMMON (decl) = 1;
1886 else if (EMPTY_CONSTRUCTOR_P (DECL_INITIAL (decl)))
1887 {
1888 DECL_COMMON (decl) = 1;
1889 DECL_INITIAL (decl) = error_mark_node;
1890 }
1891 else if (!DECL_EXPLICIT_INSTANTIATION (decl))
1892 {
1893 /* We can't do anything useful; leave vars for explicit
1894 instantiation. */
1895 DECL_EXTERNAL (decl) = 1;
1896 DECL_NOT_REALLY_EXTERN (decl) = 0;
1897 }
1898 }
1899
1900 if (TREE_PUBLIC (decl))
1901 DECL_COMDAT (decl) = 1;
1902
1903 if (VAR_P (decl))
1904 adjust_var_decl_tls_model (decl);
1905 }
1906
1907 /* For win32 we also want to put explicit instantiations in
1908 linkonce sections, so that they will be merged with implicit
1909 instantiations; otherwise we get duplicate symbol errors.
1910 For Darwin we do not want explicit instantiations to be
1911 linkonce. */
1912
1913 void
maybe_make_one_only(tree decl)1914 maybe_make_one_only (tree decl)
1915 {
1916 /* We used to say that this was not necessary on targets that support weak
1917 symbols, because the implicit instantiations will defer to the explicit
1918 one. However, that's not actually the case in SVR4; a strong definition
1919 after a weak one is an error. Also, not making explicit
1920 instantiations one_only means that we can end up with two copies of
1921 some template instantiations. */
1922 if (! flag_weak)
1923 return;
1924
1925 /* We can't set DECL_COMDAT on functions, or cp_finish_file will think
1926 we can get away with not emitting them if they aren't used. We need
1927 to for variables so that cp_finish_decl will update their linkage,
1928 because their DECL_INITIAL may not have been set properly yet. */
1929
1930 if (!TARGET_WEAK_NOT_IN_ARCHIVE_TOC
1931 || (! DECL_EXPLICIT_INSTANTIATION (decl)
1932 && ! DECL_TEMPLATE_SPECIALIZATION (decl)))
1933 {
1934 make_decl_one_only (decl, cxx_comdat_group (decl));
1935
1936 if (VAR_P (decl))
1937 {
1938 varpool_node *node = varpool_node::get_create (decl);
1939 DECL_COMDAT (decl) = 1;
1940 /* Mark it needed so we don't forget to emit it. */
1941 node->forced_by_abi = true;
1942 TREE_USED (decl) = 1;
1943
1944 adjust_var_decl_tls_model (decl);
1945 }
1946 }
1947 }
1948
1949 /* Returns true iff DECL, a FUNCTION_DECL or VAR_DECL, has vague linkage.
1950 This predicate will give the right answer during parsing of the
1951 function, which other tests may not. */
1952
1953 bool
vague_linkage_p(tree decl)1954 vague_linkage_p (tree decl)
1955 {
1956 if (!TREE_PUBLIC (decl))
1957 {
1958 /* maybe_thunk_body clears TREE_PUBLIC and DECL_ABSTRACT_P on the
1959 maybe-in-charge 'tor variants; in that case we need to check one of
1960 the "clones" for the real linkage. But only in that case; before
1961 maybe_clone_body we haven't yet copied the linkage to the clones. */
1962 if ((DECL_MAYBE_IN_CHARGE_DESTRUCTOR_P (decl)
1963 || DECL_MAYBE_IN_CHARGE_CONSTRUCTOR_P (decl))
1964 && !DECL_ABSTRACT_P (decl)
1965 && DECL_CHAIN (decl)
1966 && DECL_CLONED_FUNCTION_P (DECL_CHAIN (decl)))
1967 return vague_linkage_p (DECL_CHAIN (decl));
1968
1969 gcc_checking_assert (!DECL_COMDAT (decl));
1970 return false;
1971 }
1972 /* Unfortunately, import_export_decl has not always been called
1973 before the function is processed, so we cannot simply check
1974 DECL_COMDAT. */
1975 if (DECL_COMDAT (decl)
1976 || (TREE_CODE (decl) == FUNCTION_DECL
1977 && DECL_DECLARED_INLINE_P (decl))
1978 || (DECL_LANG_SPECIFIC (decl)
1979 && DECL_TEMPLATE_INSTANTIATION (decl))
1980 || (VAR_P (decl) && DECL_INLINE_VAR_P (decl)))
1981 return true;
1982 else if (DECL_FUNCTION_SCOPE_P (decl))
1983 /* A local static in an inline effectively has vague linkage. */
1984 return (TREE_STATIC (decl)
1985 && vague_linkage_p (DECL_CONTEXT (decl)));
1986 else
1987 return false;
1988 }
1989
1990 /* Determine whether or not we want to specifically import or export CTYPE,
1991 using various heuristics. */
1992
1993 static void
import_export_class(tree ctype)1994 import_export_class (tree ctype)
1995 {
1996 /* -1 for imported, 1 for exported. */
1997 int import_export = 0;
1998
1999 /* It only makes sense to call this function at EOF. The reason is
2000 that this function looks at whether or not the first non-inline
2001 non-abstract virtual member function has been defined in this
2002 translation unit. But, we can't possibly know that until we've
2003 seen the entire translation unit. */
2004 gcc_assert (at_eof);
2005
2006 if (CLASSTYPE_INTERFACE_KNOWN (ctype))
2007 return;
2008
2009 /* If MULTIPLE_SYMBOL_SPACES is set and we saw a #pragma interface,
2010 we will have CLASSTYPE_INTERFACE_ONLY set but not
2011 CLASSTYPE_INTERFACE_KNOWN. In that case, we don't want to use this
2012 heuristic because someone will supply a #pragma implementation
2013 elsewhere, and deducing it here would produce a conflict. */
2014 if (CLASSTYPE_INTERFACE_ONLY (ctype))
2015 return;
2016
2017 if (lookup_attribute ("dllimport", TYPE_ATTRIBUTES (ctype)))
2018 import_export = -1;
2019 else if (lookup_attribute ("dllexport", TYPE_ATTRIBUTES (ctype)))
2020 import_export = 1;
2021 else if (CLASSTYPE_IMPLICIT_INSTANTIATION (ctype)
2022 && !flag_implicit_templates)
2023 /* For a template class, without -fimplicit-templates, check the
2024 repository. If the virtual table is assigned to this
2025 translation unit, then export the class; otherwise, import
2026 it. */
2027 import_export = repo_export_class_p (ctype) ? 1 : -1;
2028 else if (TYPE_POLYMORPHIC_P (ctype))
2029 {
2030 /* The ABI specifies that the virtual table and associated
2031 information are emitted with the key method, if any. */
2032 tree method = CLASSTYPE_KEY_METHOD (ctype);
2033 /* If weak symbol support is not available, then we must be
2034 careful not to emit the vtable when the key function is
2035 inline. An inline function can be defined in multiple
2036 translation units. If we were to emit the vtable in each
2037 translation unit containing a definition, we would get
2038 multiple definition errors at link-time. */
2039 if (method && (flag_weak || ! DECL_DECLARED_INLINE_P (method)))
2040 import_export = (DECL_REALLY_EXTERN (method) ? -1 : 1);
2041 }
2042
2043 /* When MULTIPLE_SYMBOL_SPACES is set, we cannot count on seeing
2044 a definition anywhere else. */
2045 if (MULTIPLE_SYMBOL_SPACES && import_export == -1)
2046 import_export = 0;
2047
2048 /* Allow back ends the chance to overrule the decision. */
2049 if (targetm.cxx.import_export_class)
2050 import_export = targetm.cxx.import_export_class (ctype, import_export);
2051
2052 if (import_export)
2053 {
2054 SET_CLASSTYPE_INTERFACE_KNOWN (ctype);
2055 CLASSTYPE_INTERFACE_ONLY (ctype) = (import_export < 0);
2056 }
2057 }
2058
2059 /* Return true if VAR has already been provided to the back end; in that
2060 case VAR should not be modified further by the front end. */
2061 static bool
var_finalized_p(tree var)2062 var_finalized_p (tree var)
2063 {
2064 return varpool_node::get_create (var)->definition;
2065 }
2066
2067 /* DECL is a VAR_DECL or FUNCTION_DECL which, for whatever reason,
2068 must be emitted in this translation unit. Mark it as such. */
2069
2070 void
mark_needed(tree decl)2071 mark_needed (tree decl)
2072 {
2073 TREE_USED (decl) = 1;
2074 if (TREE_CODE (decl) == FUNCTION_DECL)
2075 {
2076 /* Extern inline functions don't become needed when referenced.
2077 If we know a method will be emitted in other TU and no new
2078 functions can be marked reachable, just use the external
2079 definition. */
2080 struct cgraph_node *node = cgraph_node::get_create (decl);
2081 node->forced_by_abi = true;
2082
2083 /* #pragma interface and -frepo code can call mark_needed for
2084 maybe-in-charge 'tors; mark the clones as well. */
2085 tree clone;
2086 FOR_EACH_CLONE (clone, decl)
2087 mark_needed (clone);
2088 }
2089 else if (VAR_P (decl))
2090 {
2091 varpool_node *node = varpool_node::get_create (decl);
2092 /* C++ frontend use mark_decl_references to force COMDAT variables
2093 to be output that might appear dead otherwise. */
2094 node->forced_by_abi = true;
2095 }
2096 }
2097
2098 /* DECL is either a FUNCTION_DECL or a VAR_DECL. This function
2099 returns true if a definition of this entity should be provided in
2100 this object file. Callers use this function to determine whether
2101 or not to let the back end know that a definition of DECL is
2102 available in this translation unit. */
2103
2104 bool
decl_needed_p(tree decl)2105 decl_needed_p (tree decl)
2106 {
2107 gcc_assert (VAR_OR_FUNCTION_DECL_P (decl));
2108 /* This function should only be called at the end of the translation
2109 unit. We cannot be sure of whether or not something will be
2110 COMDAT until that point. */
2111 gcc_assert (at_eof);
2112
2113 /* All entities with external linkage that are not COMDAT/EXTERN should be
2114 emitted; they may be referred to from other object files. */
2115 if (TREE_PUBLIC (decl) && !DECL_COMDAT (decl) && !DECL_REALLY_EXTERN (decl))
2116 return true;
2117 /* Functions marked "dllexport" must be emitted so that they are
2118 visible to other DLLs. */
2119 if (flag_keep_inline_dllexport
2120 && lookup_attribute ("dllexport", DECL_ATTRIBUTES (decl)))
2121 return true;
2122
2123 /* When not optimizing, do not bother to produce definitions for extern
2124 symbols. */
2125 if (DECL_REALLY_EXTERN (decl)
2126 && ((TREE_CODE (decl) != FUNCTION_DECL
2127 && !optimize)
2128 || (TREE_CODE (decl) == FUNCTION_DECL
2129 && !opt_for_fn (decl, optimize)))
2130 && !lookup_attribute ("always_inline", decl))
2131 return false;
2132
2133 /* If this entity was used, let the back end see it; it will decide
2134 whether or not to emit it into the object file. */
2135 if (TREE_USED (decl))
2136 return true;
2137
2138 /* Virtual functions might be needed for devirtualization. */
2139 if (flag_devirtualize
2140 && TREE_CODE (decl) == FUNCTION_DECL
2141 && DECL_VIRTUAL_P (decl))
2142 return true;
2143
2144 /* Otherwise, DECL does not need to be emitted -- yet. A subsequent
2145 reference to DECL might cause it to be emitted later. */
2146 return false;
2147 }
2148
2149 /* If necessary, write out the vtables for the dynamic class CTYPE.
2150 Returns true if any vtables were emitted. */
2151
2152 static bool
maybe_emit_vtables(tree ctype)2153 maybe_emit_vtables (tree ctype)
2154 {
2155 tree vtbl;
2156 tree primary_vtbl;
2157 int needed = 0;
2158 varpool_node *current = NULL, *last = NULL;
2159
2160 /* If the vtables for this class have already been emitted there is
2161 nothing more to do. */
2162 primary_vtbl = CLASSTYPE_VTABLES (ctype);
2163 if (var_finalized_p (primary_vtbl))
2164 return false;
2165 /* Ignore dummy vtables made by get_vtable_decl. */
2166 if (TREE_TYPE (primary_vtbl) == void_type_node)
2167 return false;
2168
2169 /* On some targets, we cannot determine the key method until the end
2170 of the translation unit -- which is when this function is
2171 called. */
2172 if (!targetm.cxx.key_method_may_be_inline ())
2173 determine_key_method (ctype);
2174
2175 /* See if any of the vtables are needed. */
2176 for (vtbl = CLASSTYPE_VTABLES (ctype); vtbl; vtbl = DECL_CHAIN (vtbl))
2177 {
2178 import_export_decl (vtbl);
2179 if (DECL_NOT_REALLY_EXTERN (vtbl) && decl_needed_p (vtbl))
2180 needed = 1;
2181 }
2182 if (!needed)
2183 {
2184 /* If the references to this class' vtables are optimized away,
2185 still emit the appropriate debugging information. See
2186 dfs_debug_mark. */
2187 if (DECL_COMDAT (primary_vtbl)
2188 && CLASSTYPE_DEBUG_REQUESTED (ctype))
2189 note_debug_info_needed (ctype);
2190 return false;
2191 }
2192
2193 /* The ABI requires that we emit all of the vtables if we emit any
2194 of them. */
2195 for (vtbl = CLASSTYPE_VTABLES (ctype); vtbl; vtbl = DECL_CHAIN (vtbl))
2196 {
2197 /* Mark entities references from the virtual table as used. */
2198 mark_vtable_entries (vtbl);
2199
2200 if (TREE_TYPE (DECL_INITIAL (vtbl)) == 0)
2201 {
2202 vec<tree, va_gc> *cleanups = NULL;
2203 tree expr = store_init_value (vtbl, DECL_INITIAL (vtbl), &cleanups,
2204 LOOKUP_NORMAL);
2205
2206 /* It had better be all done at compile-time. */
2207 gcc_assert (!expr && !cleanups);
2208 }
2209
2210 /* Write it out. */
2211 DECL_EXTERNAL (vtbl) = 0;
2212 rest_of_decl_compilation (vtbl, 1, 1);
2213
2214 /* Because we're only doing syntax-checking, we'll never end up
2215 actually marking the variable as written. */
2216 if (flag_syntax_only)
2217 TREE_ASM_WRITTEN (vtbl) = 1;
2218 else if (DECL_ONE_ONLY (vtbl))
2219 {
2220 current = varpool_node::get_create (vtbl);
2221 if (last)
2222 current->add_to_same_comdat_group (last);
2223 last = current;
2224 }
2225 }
2226
2227 /* Since we're writing out the vtable here, also write the debug
2228 info. */
2229 note_debug_info_needed (ctype);
2230
2231 return true;
2232 }
2233
2234 /* A special return value from type_visibility meaning internal
2235 linkage. */
2236
2237 enum { VISIBILITY_ANON = VISIBILITY_INTERNAL+1 };
2238
2239 /* walk_tree helper function for type_visibility. */
2240
2241 static tree
min_vis_r(tree * tp,int * walk_subtrees,void * data)2242 min_vis_r (tree *tp, int *walk_subtrees, void *data)
2243 {
2244 int *vis_p = (int *)data;
2245 if (! TYPE_P (*tp))
2246 {
2247 *walk_subtrees = 0;
2248 }
2249 else if (OVERLOAD_TYPE_P (*tp)
2250 && !TREE_PUBLIC (TYPE_MAIN_DECL (*tp)))
2251 {
2252 *vis_p = VISIBILITY_ANON;
2253 return *tp;
2254 }
2255 else if (CLASS_TYPE_P (*tp)
2256 && CLASSTYPE_VISIBILITY (*tp) > *vis_p)
2257 *vis_p = CLASSTYPE_VISIBILITY (*tp);
2258 return NULL;
2259 }
2260
2261 /* Returns the visibility of TYPE, which is the minimum visibility of its
2262 component types. */
2263
2264 static int
type_visibility(tree type)2265 type_visibility (tree type)
2266 {
2267 int vis = VISIBILITY_DEFAULT;
2268 cp_walk_tree_without_duplicates (&type, min_vis_r, &vis);
2269 return vis;
2270 }
2271
2272 /* Limit the visibility of DECL to VISIBILITY, if not explicitly
2273 specified (or if VISIBILITY is static). If TMPL is true, this
2274 constraint is for a template argument, and takes precedence
2275 over explicitly-specified visibility on the template. */
2276
2277 static void
constrain_visibility(tree decl,int visibility,bool tmpl)2278 constrain_visibility (tree decl, int visibility, bool tmpl)
2279 {
2280 if (visibility == VISIBILITY_ANON)
2281 {
2282 /* extern "C" declarations aren't affected by the anonymous
2283 namespace. */
2284 if (!DECL_EXTERN_C_P (decl))
2285 {
2286 TREE_PUBLIC (decl) = 0;
2287 DECL_WEAK (decl) = 0;
2288 DECL_COMMON (decl) = 0;
2289 DECL_COMDAT (decl) = false;
2290 if (VAR_OR_FUNCTION_DECL_P (decl))
2291 {
2292 struct symtab_node *snode = symtab_node::get (decl);
2293
2294 if (snode)
2295 snode->set_comdat_group (NULL);
2296 }
2297 DECL_INTERFACE_KNOWN (decl) = 1;
2298 if (DECL_LANG_SPECIFIC (decl))
2299 DECL_NOT_REALLY_EXTERN (decl) = 1;
2300 }
2301 }
2302 else if (visibility > DECL_VISIBILITY (decl)
2303 && (tmpl || !DECL_VISIBILITY_SPECIFIED (decl)))
2304 {
2305 DECL_VISIBILITY (decl) = (enum symbol_visibility) visibility;
2306 /* This visibility was not specified. */
2307 DECL_VISIBILITY_SPECIFIED (decl) = false;
2308 }
2309 }
2310
2311 /* Constrain the visibility of DECL based on the visibility of its template
2312 arguments. */
2313
2314 static void
constrain_visibility_for_template(tree decl,tree targs)2315 constrain_visibility_for_template (tree decl, tree targs)
2316 {
2317 /* If this is a template instantiation, check the innermost
2318 template args for visibility constraints. The outer template
2319 args are covered by the class check. */
2320 tree args = INNERMOST_TEMPLATE_ARGS (targs);
2321 int i;
2322 for (i = TREE_VEC_LENGTH (args); i > 0; --i)
2323 {
2324 int vis = 0;
2325
2326 tree arg = TREE_VEC_ELT (args, i-1);
2327 if (TYPE_P (arg))
2328 vis = type_visibility (arg);
2329 else
2330 {
2331 if (REFERENCE_REF_P (arg))
2332 arg = TREE_OPERAND (arg, 0);
2333 if (TREE_TYPE (arg))
2334 STRIP_NOPS (arg);
2335 if (TREE_CODE (arg) == ADDR_EXPR)
2336 arg = TREE_OPERAND (arg, 0);
2337 if (VAR_OR_FUNCTION_DECL_P (arg))
2338 {
2339 if (! TREE_PUBLIC (arg))
2340 vis = VISIBILITY_ANON;
2341 else
2342 vis = DECL_VISIBILITY (arg);
2343 }
2344 }
2345 if (vis)
2346 constrain_visibility (decl, vis, true);
2347 }
2348 }
2349
2350 /* Like c_determine_visibility, but with additional C++-specific
2351 behavior.
2352
2353 Function-scope entities can rely on the function's visibility because
2354 it is set in start_preparsed_function.
2355
2356 Class-scope entities cannot rely on the class's visibility until the end
2357 of the enclosing class definition.
2358
2359 Note that because namespaces have multiple independent definitions,
2360 namespace visibility is handled elsewhere using the #pragma visibility
2361 machinery rather than by decorating the namespace declaration.
2362
2363 The goal is for constraints from the type to give a diagnostic, and
2364 other constraints to be applied silently. */
2365
2366 void
determine_visibility(tree decl)2367 determine_visibility (tree decl)
2368 {
2369 /* Remember that all decls get VISIBILITY_DEFAULT when built. */
2370
2371 /* Only relevant for names with external linkage. */
2372 if (!TREE_PUBLIC (decl))
2373 return;
2374
2375 /* Cloned constructors and destructors get the same visibility as
2376 the underlying function. That should be set up in
2377 maybe_clone_body. */
2378 gcc_assert (!DECL_CLONED_FUNCTION_P (decl));
2379
2380 bool orig_visibility_specified = DECL_VISIBILITY_SPECIFIED (decl);
2381 enum symbol_visibility orig_visibility = DECL_VISIBILITY (decl);
2382
2383 /* The decl may be a template instantiation, which could influence
2384 visibilty. */
2385 tree template_decl = NULL_TREE;
2386 if (TREE_CODE (decl) == TYPE_DECL)
2387 {
2388 if (CLASS_TYPE_P (TREE_TYPE (decl)))
2389 {
2390 if (CLASSTYPE_USE_TEMPLATE (TREE_TYPE (decl)))
2391 template_decl = decl;
2392 }
2393 else if (TYPE_TEMPLATE_INFO (TREE_TYPE (decl)))
2394 template_decl = decl;
2395 }
2396 else if (DECL_LANG_SPECIFIC (decl) && DECL_USE_TEMPLATE (decl))
2397 template_decl = decl;
2398
2399 /* If DECL is a member of a class, visibility specifiers on the
2400 class can influence the visibility of the DECL. */
2401 tree class_type = NULL_TREE;
2402 if (DECL_CLASS_SCOPE_P (decl))
2403 class_type = DECL_CONTEXT (decl);
2404 else
2405 {
2406 /* Not a class member. */
2407
2408 /* Virtual tables have DECL_CONTEXT set to their associated class,
2409 so they are automatically handled above. */
2410 gcc_assert (!VAR_P (decl)
2411 || !DECL_VTABLE_OR_VTT_P (decl));
2412
2413 if (DECL_FUNCTION_SCOPE_P (decl) && ! DECL_VISIBILITY_SPECIFIED (decl))
2414 {
2415 /* Local statics and classes get the visibility of their
2416 containing function by default, except that
2417 -fvisibility-inlines-hidden doesn't affect them. */
2418 tree fn = DECL_CONTEXT (decl);
2419 if (DECL_VISIBILITY_SPECIFIED (fn))
2420 {
2421 DECL_VISIBILITY (decl) = DECL_VISIBILITY (fn);
2422 DECL_VISIBILITY_SPECIFIED (decl) =
2423 DECL_VISIBILITY_SPECIFIED (fn);
2424 }
2425 else
2426 {
2427 if (DECL_CLASS_SCOPE_P (fn))
2428 determine_visibility_from_class (decl, DECL_CONTEXT (fn));
2429 else if (determine_hidden_inline (fn))
2430 {
2431 DECL_VISIBILITY (decl) = default_visibility;
2432 DECL_VISIBILITY_SPECIFIED (decl) =
2433 visibility_options.inpragma;
2434 }
2435 else
2436 {
2437 DECL_VISIBILITY (decl) = DECL_VISIBILITY (fn);
2438 DECL_VISIBILITY_SPECIFIED (decl) =
2439 DECL_VISIBILITY_SPECIFIED (fn);
2440 }
2441 }
2442
2443 /* Local classes in templates have CLASSTYPE_USE_TEMPLATE set,
2444 but have no TEMPLATE_INFO, so don't try to check it. */
2445 template_decl = NULL_TREE;
2446 }
2447 else if (VAR_P (decl) && DECL_TINFO_P (decl)
2448 && flag_visibility_ms_compat)
2449 {
2450 /* Under -fvisibility-ms-compat, types are visible by default,
2451 even though their contents aren't. */
2452 tree underlying_type = TREE_TYPE (DECL_NAME (decl));
2453 int underlying_vis = type_visibility (underlying_type);
2454 if (underlying_vis == VISIBILITY_ANON
2455 || (CLASS_TYPE_P (underlying_type)
2456 && CLASSTYPE_VISIBILITY_SPECIFIED (underlying_type)))
2457 constrain_visibility (decl, underlying_vis, false);
2458 else
2459 DECL_VISIBILITY (decl) = VISIBILITY_DEFAULT;
2460 }
2461 else if (VAR_P (decl) && DECL_TINFO_P (decl))
2462 {
2463 /* tinfo visibility is based on the type it's for. */
2464 constrain_visibility
2465 (decl, type_visibility (TREE_TYPE (DECL_NAME (decl))), false);
2466
2467 /* Give the target a chance to override the visibility associated
2468 with DECL. */
2469 if (TREE_PUBLIC (decl)
2470 && !DECL_REALLY_EXTERN (decl)
2471 && CLASS_TYPE_P (TREE_TYPE (DECL_NAME (decl)))
2472 && !CLASSTYPE_VISIBILITY_SPECIFIED (TREE_TYPE (DECL_NAME (decl))))
2473 targetm.cxx.determine_class_data_visibility (decl);
2474 }
2475 else if (template_decl)
2476 /* Template instantiations and specializations get visibility based
2477 on their template unless they override it with an attribute. */;
2478 else if (! DECL_VISIBILITY_SPECIFIED (decl))
2479 {
2480 if (determine_hidden_inline (decl))
2481 DECL_VISIBILITY (decl) = VISIBILITY_HIDDEN;
2482 else
2483 {
2484 /* Set default visibility to whatever the user supplied with
2485 #pragma GCC visibility or a namespace visibility attribute. */
2486 DECL_VISIBILITY (decl) = default_visibility;
2487 DECL_VISIBILITY_SPECIFIED (decl) = visibility_options.inpragma;
2488 }
2489 }
2490 }
2491
2492 if (template_decl)
2493 {
2494 /* If the specialization doesn't specify visibility, use the
2495 visibility from the template. */
2496 tree tinfo = get_template_info (template_decl);
2497 tree args = TI_ARGS (tinfo);
2498 tree attribs = (TREE_CODE (decl) == TYPE_DECL
2499 ? TYPE_ATTRIBUTES (TREE_TYPE (decl))
2500 : DECL_ATTRIBUTES (decl));
2501
2502 if (args != error_mark_node)
2503 {
2504 tree pattern = DECL_TEMPLATE_RESULT (TI_TEMPLATE (tinfo));
2505
2506 if (!DECL_VISIBILITY_SPECIFIED (decl))
2507 {
2508 if (!DECL_VISIBILITY_SPECIFIED (pattern)
2509 && determine_hidden_inline (decl))
2510 DECL_VISIBILITY (decl) = VISIBILITY_HIDDEN;
2511 else
2512 {
2513 DECL_VISIBILITY (decl) = DECL_VISIBILITY (pattern);
2514 DECL_VISIBILITY_SPECIFIED (decl)
2515 = DECL_VISIBILITY_SPECIFIED (pattern);
2516 }
2517 }
2518
2519 if (args
2520 /* Template argument visibility outweighs #pragma or namespace
2521 visibility, but not an explicit attribute. */
2522 && !lookup_attribute ("visibility", attribs))
2523 {
2524 int depth = TMPL_ARGS_DEPTH (args);
2525 if (DECL_VISIBILITY_SPECIFIED (decl))
2526 {
2527 /* A class template member with explicit visibility
2528 overrides the class visibility, so we need to apply
2529 all the levels of template args directly. */
2530 int i;
2531 for (i = 1; i <= depth; ++i)
2532 {
2533 tree lev = TMPL_ARGS_LEVEL (args, i);
2534 constrain_visibility_for_template (decl, lev);
2535 }
2536 }
2537 else if (PRIMARY_TEMPLATE_P (TI_TEMPLATE (tinfo)))
2538 /* Limit visibility based on its template arguments. */
2539 constrain_visibility_for_template (decl, args);
2540 }
2541 }
2542 }
2543
2544 if (class_type)
2545 determine_visibility_from_class (decl, class_type);
2546
2547 if (decl_anon_ns_mem_p (decl))
2548 /* Names in an anonymous namespace get internal linkage.
2549 This might change once we implement export. */
2550 constrain_visibility (decl, VISIBILITY_ANON, false);
2551 else if (TREE_CODE (decl) != TYPE_DECL)
2552 {
2553 /* Propagate anonymity from type to decl. */
2554 int tvis = type_visibility (TREE_TYPE (decl));
2555 if (tvis == VISIBILITY_ANON
2556 || ! DECL_VISIBILITY_SPECIFIED (decl))
2557 constrain_visibility (decl, tvis, false);
2558 }
2559 else if (no_linkage_check (TREE_TYPE (decl), /*relaxed_p=*/true))
2560 /* DR 757: A type without linkage shall not be used as the type of a
2561 variable or function with linkage, unless
2562 o the variable or function has extern "C" linkage (7.5 [dcl.link]), or
2563 o the variable or function is not used (3.2 [basic.def.odr]) or is
2564 defined in the same translation unit.
2565
2566 Since non-extern "C" decls need to be defined in the same
2567 translation unit, we can make the type internal. */
2568 constrain_visibility (decl, VISIBILITY_ANON, false);
2569
2570 /* If visibility changed and DECL already has DECL_RTL, ensure
2571 symbol flags are updated. */
2572 if ((DECL_VISIBILITY (decl) != orig_visibility
2573 || DECL_VISIBILITY_SPECIFIED (decl) != orig_visibility_specified)
2574 && ((VAR_P (decl) && TREE_STATIC (decl))
2575 || TREE_CODE (decl) == FUNCTION_DECL)
2576 && DECL_RTL_SET_P (decl))
2577 make_decl_rtl (decl);
2578 }
2579
2580 /* By default, static data members and function members receive
2581 the visibility of their containing class. */
2582
2583 static void
determine_visibility_from_class(tree decl,tree class_type)2584 determine_visibility_from_class (tree decl, tree class_type)
2585 {
2586 if (DECL_VISIBILITY_SPECIFIED (decl))
2587 return;
2588
2589 if (determine_hidden_inline (decl))
2590 DECL_VISIBILITY (decl) = VISIBILITY_HIDDEN;
2591 else
2592 {
2593 /* Default to the class visibility. */
2594 DECL_VISIBILITY (decl) = CLASSTYPE_VISIBILITY (class_type);
2595 DECL_VISIBILITY_SPECIFIED (decl)
2596 = CLASSTYPE_VISIBILITY_SPECIFIED (class_type);
2597 }
2598
2599 /* Give the target a chance to override the visibility associated
2600 with DECL. */
2601 if (VAR_P (decl)
2602 && (DECL_TINFO_P (decl)
2603 || (DECL_VTABLE_OR_VTT_P (decl)
2604 /* Construction virtual tables are not exported because
2605 they cannot be referred to from other object files;
2606 their name is not standardized by the ABI. */
2607 && !DECL_CONSTRUCTION_VTABLE_P (decl)))
2608 && TREE_PUBLIC (decl)
2609 && !DECL_REALLY_EXTERN (decl)
2610 && !CLASSTYPE_VISIBILITY_SPECIFIED (class_type))
2611 targetm.cxx.determine_class_data_visibility (decl);
2612 }
2613
2614 /* Returns true iff DECL is an inline that should get hidden visibility
2615 because of -fvisibility-inlines-hidden. */
2616
2617 static bool
determine_hidden_inline(tree decl)2618 determine_hidden_inline (tree decl)
2619 {
2620 return (visibility_options.inlines_hidden
2621 /* Don't do this for inline templates; specializations might not be
2622 inline, and we don't want them to inherit the hidden
2623 visibility. We'll set it here for all inline instantiations. */
2624 && !processing_template_decl
2625 && TREE_CODE (decl) == FUNCTION_DECL
2626 && DECL_DECLARED_INLINE_P (decl)
2627 && (! DECL_LANG_SPECIFIC (decl)
2628 || ! DECL_EXPLICIT_INSTANTIATION (decl)));
2629 }
2630
2631 /* Constrain the visibility of a class TYPE based on the visibility of its
2632 field types. Warn if any fields require lesser visibility. */
2633
2634 void
constrain_class_visibility(tree type)2635 constrain_class_visibility (tree type)
2636 {
2637 tree binfo;
2638 tree t;
2639 int i;
2640
2641 int vis = type_visibility (type);
2642
2643 if (vis == VISIBILITY_ANON
2644 || DECL_IN_SYSTEM_HEADER (TYPE_MAIN_DECL (type)))
2645 return;
2646
2647 /* Don't warn about visibility if the class has explicit visibility. */
2648 if (CLASSTYPE_VISIBILITY_SPECIFIED (type))
2649 vis = VISIBILITY_INTERNAL;
2650
2651 for (t = TYPE_FIELDS (type); t; t = DECL_CHAIN (t))
2652 if (TREE_CODE (t) == FIELD_DECL && TREE_TYPE (t) != error_mark_node
2653 && !DECL_ARTIFICIAL (t))
2654 {
2655 tree ftype = strip_pointer_or_array_types (TREE_TYPE (t));
2656 int subvis = type_visibility (ftype);
2657
2658 if (subvis == VISIBILITY_ANON)
2659 {
2660 if (!in_main_input_context())
2661 {
2662 tree nlt = no_linkage_check (ftype, /*relaxed_p=*/false);
2663 if (nlt)
2664 {
2665 if (same_type_p (TREE_TYPE (t), nlt))
2666 warning (OPT_Wsubobject_linkage, "\
2667 %qT has a field %qD whose type has no linkage",
2668 type, t);
2669 else
2670 warning (OPT_Wsubobject_linkage, "\
2671 %qT has a field %qD whose type depends on the type %qT which has no linkage",
2672 type, t, nlt);
2673 }
2674 else
2675 warning (OPT_Wsubobject_linkage, "\
2676 %qT has a field %qD whose type uses the anonymous namespace",
2677 type, t);
2678 }
2679 }
2680 else if (MAYBE_CLASS_TYPE_P (ftype)
2681 && vis < VISIBILITY_HIDDEN
2682 && subvis >= VISIBILITY_HIDDEN)
2683 warning (OPT_Wattributes, "\
2684 %qT declared with greater visibility than the type of its field %qD",
2685 type, t);
2686 }
2687
2688 binfo = TYPE_BINFO (type);
2689 for (i = 0; BINFO_BASE_ITERATE (binfo, i, t); ++i)
2690 {
2691 int subvis = type_visibility (TREE_TYPE (t));
2692
2693 if (subvis == VISIBILITY_ANON)
2694 {
2695 if (!in_main_input_context())
2696 {
2697 tree nlt = no_linkage_check (TREE_TYPE (t), /*relaxed_p=*/false);
2698 if (nlt)
2699 {
2700 if (same_type_p (TREE_TYPE (t), nlt))
2701 warning (OPT_Wsubobject_linkage, "\
2702 %qT has a base %qT whose type has no linkage",
2703 type, TREE_TYPE (t));
2704 else
2705 warning (OPT_Wsubobject_linkage, "\
2706 %qT has a base %qT whose type depends on the type %qT which has no linkage",
2707 type, TREE_TYPE (t), nlt);
2708 }
2709 else
2710 warning (OPT_Wsubobject_linkage, "\
2711 %qT has a base %qT whose type uses the anonymous namespace",
2712 type, TREE_TYPE (t));
2713 }
2714 }
2715 else if (vis < VISIBILITY_HIDDEN
2716 && subvis >= VISIBILITY_HIDDEN)
2717 warning (OPT_Wattributes, "\
2718 %qT declared with greater visibility than its base %qT",
2719 type, TREE_TYPE (t));
2720 }
2721 }
2722
2723 /* Functions for adjusting the visibility of a tagged type and its nested
2724 types and declarations when it gets a name for linkage purposes from a
2725 typedef. */
2726
2727 static void bt_reset_linkage_1 (binding_entry, void *);
2728 static void bt_reset_linkage_2 (binding_entry, void *);
2729
2730 /* First reset the visibility of all the types. */
2731
2732 static void
reset_type_linkage_1(tree type)2733 reset_type_linkage_1 (tree type)
2734 {
2735 set_linkage_according_to_type (type, TYPE_MAIN_DECL (type));
2736 if (CLASS_TYPE_P (type))
2737 binding_table_foreach (CLASSTYPE_NESTED_UTDS (type),
2738 bt_reset_linkage_1, NULL);
2739 }
2740 static void
bt_reset_linkage_1(binding_entry b,void *)2741 bt_reset_linkage_1 (binding_entry b, void */*data*/)
2742 {
2743 reset_type_linkage_1 (b->type);
2744 }
2745
2746 /* Then reset the visibility of any static data members or member
2747 functions that use those types. */
2748
2749 static void
reset_decl_linkage(tree decl)2750 reset_decl_linkage (tree decl)
2751 {
2752 if (TREE_PUBLIC (decl))
2753 return;
2754 if (DECL_CLONED_FUNCTION_P (decl))
2755 return;
2756 TREE_PUBLIC (decl) = true;
2757 DECL_INTERFACE_KNOWN (decl) = false;
2758 determine_visibility (decl);
2759 tentative_decl_linkage (decl);
2760 }
2761
2762 static void
reset_type_linkage_2(tree type)2763 reset_type_linkage_2 (tree type)
2764 {
2765 if (CLASS_TYPE_P (type))
2766 {
2767 if (tree vt = CLASSTYPE_VTABLES (type))
2768 {
2769 tree name = mangle_vtbl_for_type (type);
2770 DECL_NAME (vt) = name;
2771 SET_DECL_ASSEMBLER_NAME (vt, name);
2772 reset_decl_linkage (vt);
2773 }
2774 if (tree ti = CLASSTYPE_TYPEINFO_VAR (type))
2775 {
2776 tree name = mangle_typeinfo_for_type (type);
2777 DECL_NAME (ti) = name;
2778 SET_DECL_ASSEMBLER_NAME (ti, name);
2779 TREE_TYPE (name) = type;
2780 reset_decl_linkage (ti);
2781 }
2782 for (tree m = TYPE_FIELDS (type); m; m = DECL_CHAIN (m))
2783 {
2784 tree mem = STRIP_TEMPLATE (m);
2785 if (TREE_CODE (mem) == VAR_DECL || TREE_CODE (mem) == FUNCTION_DECL)
2786 reset_decl_linkage (mem);
2787 }
2788 binding_table_foreach (CLASSTYPE_NESTED_UTDS (type),
2789 bt_reset_linkage_2, NULL);
2790 }
2791 }
2792
2793 static void
bt_reset_linkage_2(binding_entry b,void *)2794 bt_reset_linkage_2 (binding_entry b, void */*data*/)
2795 {
2796 reset_type_linkage_2 (b->type);
2797 }
2798 void
reset_type_linkage(tree type)2799 reset_type_linkage (tree type)
2800 {
2801 reset_type_linkage_1 (type);
2802 reset_type_linkage_2 (type);
2803 }
2804
2805 /* Set up our initial idea of what the linkage of DECL should be. */
2806
2807 void
tentative_decl_linkage(tree decl)2808 tentative_decl_linkage (tree decl)
2809 {
2810 if (DECL_INTERFACE_KNOWN (decl))
2811 /* We've already made a decision as to how this function will
2812 be handled. */;
2813 else if (vague_linkage_p (decl))
2814 {
2815 if (TREE_CODE (decl) == FUNCTION_DECL
2816 && decl_defined_p (decl))
2817 {
2818 DECL_EXTERNAL (decl) = 1;
2819 DECL_NOT_REALLY_EXTERN (decl) = 1;
2820 note_vague_linkage_fn (decl);
2821 /* A non-template inline function with external linkage will
2822 always be COMDAT. As we must eventually determine the
2823 linkage of all functions, and as that causes writes to
2824 the data mapped in from the PCH file, it's advantageous
2825 to mark the functions at this point. */
2826 if (DECL_DECLARED_INLINE_P (decl)
2827 && (!DECL_IMPLICIT_INSTANTIATION (decl)
2828 || DECL_DEFAULTED_FN (decl)))
2829 {
2830 /* This function must have external linkage, as
2831 otherwise DECL_INTERFACE_KNOWN would have been
2832 set. */
2833 gcc_assert (TREE_PUBLIC (decl));
2834 comdat_linkage (decl);
2835 DECL_INTERFACE_KNOWN (decl) = 1;
2836 }
2837 }
2838 else if (VAR_P (decl))
2839 maybe_commonize_var (decl);
2840 }
2841 }
2842
2843 /* DECL is a FUNCTION_DECL or VAR_DECL. If the object file linkage
2844 for DECL has not already been determined, do so now by setting
2845 DECL_EXTERNAL, DECL_COMDAT and other related flags. Until this
2846 function is called entities with vague linkage whose definitions
2847 are available must have TREE_PUBLIC set.
2848
2849 If this function decides to place DECL in COMDAT, it will set
2850 appropriate flags -- but will not clear DECL_EXTERNAL. It is up to
2851 the caller to decide whether or not to clear DECL_EXTERNAL. Some
2852 callers defer that decision until it is clear that DECL is actually
2853 required. */
2854
2855 void
import_export_decl(tree decl)2856 import_export_decl (tree decl)
2857 {
2858 int emit_p;
2859 bool comdat_p;
2860 bool import_p;
2861 tree class_type = NULL_TREE;
2862
2863 if (DECL_INTERFACE_KNOWN (decl))
2864 return;
2865
2866 /* We cannot determine what linkage to give to an entity with vague
2867 linkage until the end of the file. For example, a virtual table
2868 for a class will be defined if and only if the key method is
2869 defined in this translation unit. As a further example, consider
2870 that when compiling a translation unit that uses PCH file with
2871 "-frepo" it would be incorrect to make decisions about what
2872 entities to emit when building the PCH; those decisions must be
2873 delayed until the repository information has been processed. */
2874 gcc_assert (at_eof);
2875 /* Object file linkage for explicit instantiations is handled in
2876 mark_decl_instantiated. For static variables in functions with
2877 vague linkage, maybe_commonize_var is used.
2878
2879 Therefore, the only declarations that should be provided to this
2880 function are those with external linkage that are:
2881
2882 * implicit instantiations of function templates
2883
2884 * inline function
2885
2886 * implicit instantiations of static data members of class
2887 templates
2888
2889 * virtual tables
2890
2891 * typeinfo objects
2892
2893 Furthermore, all entities that reach this point must have a
2894 definition available in this translation unit.
2895
2896 The following assertions check these conditions. */
2897 gcc_assert (VAR_OR_FUNCTION_DECL_P (decl));
2898 /* Any code that creates entities with TREE_PUBLIC cleared should
2899 also set DECL_INTERFACE_KNOWN. */
2900 gcc_assert (TREE_PUBLIC (decl));
2901 if (TREE_CODE (decl) == FUNCTION_DECL)
2902 gcc_assert (DECL_IMPLICIT_INSTANTIATION (decl)
2903 || DECL_FRIEND_PSEUDO_TEMPLATE_INSTANTIATION (decl)
2904 || DECL_DECLARED_INLINE_P (decl));
2905 else
2906 gcc_assert (DECL_IMPLICIT_INSTANTIATION (decl)
2907 || DECL_VTABLE_OR_VTT_P (decl)
2908 || DECL_TINFO_P (decl));
2909 /* Check that a definition of DECL is available in this translation
2910 unit. */
2911 gcc_assert (!DECL_REALLY_EXTERN (decl));
2912
2913 /* Assume that DECL will not have COMDAT linkage. */
2914 comdat_p = false;
2915 /* Assume that DECL will not be imported into this translation
2916 unit. */
2917 import_p = false;
2918
2919 /* See if the repository tells us whether or not to emit DECL in
2920 this translation unit. */
2921 emit_p = repo_emit_p (decl);
2922 if (emit_p == 0)
2923 import_p = true;
2924 else if (emit_p == 1)
2925 {
2926 /* The repository indicates that this entity should be defined
2927 here. Make sure the back end honors that request. */
2928 mark_needed (decl);
2929 /* Output the definition as an ordinary strong definition. */
2930 DECL_EXTERNAL (decl) = 0;
2931 DECL_INTERFACE_KNOWN (decl) = 1;
2932 return;
2933 }
2934
2935 if (import_p)
2936 /* We have already decided what to do with this DECL; there is no
2937 need to check anything further. */
2938 ;
2939 else if (VAR_P (decl) && DECL_VTABLE_OR_VTT_P (decl))
2940 {
2941 class_type = DECL_CONTEXT (decl);
2942 import_export_class (class_type);
2943 if (CLASSTYPE_INTERFACE_KNOWN (class_type)
2944 && CLASSTYPE_INTERFACE_ONLY (class_type))
2945 import_p = true;
2946 else if ((!flag_weak || TARGET_WEAK_NOT_IN_ARCHIVE_TOC)
2947 && !CLASSTYPE_USE_TEMPLATE (class_type)
2948 && CLASSTYPE_KEY_METHOD (class_type)
2949 && !DECL_DECLARED_INLINE_P (CLASSTYPE_KEY_METHOD (class_type)))
2950 /* The ABI requires that all virtual tables be emitted with
2951 COMDAT linkage. However, on systems where COMDAT symbols
2952 don't show up in the table of contents for a static
2953 archive, or on systems without weak symbols (where we
2954 approximate COMDAT linkage by using internal linkage), the
2955 linker will report errors about undefined symbols because
2956 it will not see the virtual table definition. Therefore,
2957 in the case that we know that the virtual table will be
2958 emitted in only one translation unit, we make the virtual
2959 table an ordinary definition with external linkage. */
2960 DECL_EXTERNAL (decl) = 0;
2961 else if (CLASSTYPE_INTERFACE_KNOWN (class_type))
2962 {
2963 /* CLASS_TYPE is being exported from this translation unit,
2964 so DECL should be defined here. */
2965 if (!flag_weak && CLASSTYPE_EXPLICIT_INSTANTIATION (class_type))
2966 /* If a class is declared in a header with the "extern
2967 template" extension, then it will not be instantiated,
2968 even in translation units that would normally require
2969 it. Often such classes are explicitly instantiated in
2970 one translation unit. Therefore, the explicit
2971 instantiation must be made visible to other translation
2972 units. */
2973 DECL_EXTERNAL (decl) = 0;
2974 else
2975 {
2976 /* The generic C++ ABI says that class data is always
2977 COMDAT, even if there is a key function. Some
2978 variants (e.g., the ARM EABI) says that class data
2979 only has COMDAT linkage if the class data might be
2980 emitted in more than one translation unit. When the
2981 key method can be inline and is inline, we still have
2982 to arrange for comdat even though
2983 class_data_always_comdat is false. */
2984 if (!CLASSTYPE_KEY_METHOD (class_type)
2985 || DECL_DECLARED_INLINE_P (CLASSTYPE_KEY_METHOD (class_type))
2986 || targetm.cxx.class_data_always_comdat ())
2987 {
2988 /* The ABI requires COMDAT linkage. Normally, we
2989 only emit COMDAT things when they are needed;
2990 make sure that we realize that this entity is
2991 indeed needed. */
2992 comdat_p = true;
2993 mark_needed (decl);
2994 }
2995 }
2996 }
2997 else if (!flag_implicit_templates
2998 && CLASSTYPE_IMPLICIT_INSTANTIATION (class_type))
2999 import_p = true;
3000 else
3001 comdat_p = true;
3002 }
3003 else if (VAR_P (decl) && DECL_TINFO_P (decl))
3004 {
3005 tree type = TREE_TYPE (DECL_NAME (decl));
3006 if (CLASS_TYPE_P (type))
3007 {
3008 class_type = type;
3009 import_export_class (type);
3010 if (CLASSTYPE_INTERFACE_KNOWN (type)
3011 && TYPE_POLYMORPHIC_P (type)
3012 && CLASSTYPE_INTERFACE_ONLY (type)
3013 /* If -fno-rtti was specified, then we cannot be sure
3014 that RTTI information will be emitted with the
3015 virtual table of the class, so we must emit it
3016 wherever it is used. */
3017 && flag_rtti)
3018 import_p = true;
3019 else
3020 {
3021 if (CLASSTYPE_INTERFACE_KNOWN (type)
3022 && !CLASSTYPE_INTERFACE_ONLY (type))
3023 {
3024 comdat_p = (targetm.cxx.class_data_always_comdat ()
3025 || (CLASSTYPE_KEY_METHOD (type)
3026 && DECL_DECLARED_INLINE_P (CLASSTYPE_KEY_METHOD (type))));
3027 mark_needed (decl);
3028 if (!flag_weak)
3029 {
3030 comdat_p = false;
3031 DECL_EXTERNAL (decl) = 0;
3032 }
3033 }
3034 else
3035 comdat_p = true;
3036 }
3037 }
3038 else
3039 comdat_p = true;
3040 }
3041 else if (DECL_TEMPLOID_INSTANTIATION (decl))
3042 {
3043 /* DECL is an implicit instantiation of a function or static
3044 data member. */
3045 if ((flag_implicit_templates
3046 && !flag_use_repository)
3047 || (flag_implicit_inline_templates
3048 && TREE_CODE (decl) == FUNCTION_DECL
3049 && DECL_DECLARED_INLINE_P (decl)))
3050 comdat_p = true;
3051 else
3052 /* If we are not implicitly generating templates, then mark
3053 this entity as undefined in this translation unit. */
3054 import_p = true;
3055 }
3056 else if (DECL_FUNCTION_MEMBER_P (decl))
3057 {
3058 if (!DECL_DECLARED_INLINE_P (decl))
3059 {
3060 tree ctype = DECL_CONTEXT (decl);
3061 import_export_class (ctype);
3062 if (CLASSTYPE_INTERFACE_KNOWN (ctype))
3063 {
3064 DECL_NOT_REALLY_EXTERN (decl)
3065 = ! (CLASSTYPE_INTERFACE_ONLY (ctype)
3066 || (DECL_DECLARED_INLINE_P (decl)
3067 && ! flag_implement_inlines
3068 && !DECL_VINDEX (decl)));
3069
3070 if (!DECL_NOT_REALLY_EXTERN (decl))
3071 DECL_EXTERNAL (decl) = 1;
3072
3073 /* Always make artificials weak. */
3074 if (DECL_ARTIFICIAL (decl) && flag_weak)
3075 comdat_p = true;
3076 else
3077 maybe_make_one_only (decl);
3078 }
3079 }
3080 else
3081 comdat_p = true;
3082 }
3083 else
3084 comdat_p = true;
3085
3086 if (import_p)
3087 {
3088 /* If we are importing DECL into this translation unit, mark is
3089 an undefined here. */
3090 DECL_EXTERNAL (decl) = 1;
3091 DECL_NOT_REALLY_EXTERN (decl) = 0;
3092 }
3093 else if (comdat_p)
3094 {
3095 /* If we decided to put DECL in COMDAT, mark it accordingly at
3096 this point. */
3097 comdat_linkage (decl);
3098 }
3099
3100 DECL_INTERFACE_KNOWN (decl) = 1;
3101 }
3102
3103 /* Return an expression that performs the destruction of DECL, which
3104 must be a VAR_DECL whose type has a non-trivial destructor, or is
3105 an array whose (innermost) elements have a non-trivial destructor. */
3106
3107 tree
build_cleanup(tree decl)3108 build_cleanup (tree decl)
3109 {
3110 tree clean = cxx_maybe_build_cleanup (decl, tf_warning_or_error);
3111 gcc_assert (clean != NULL_TREE);
3112 return clean;
3113 }
3114
3115 /* Returns the initialization guard variable for the variable DECL,
3116 which has static storage duration. */
3117
3118 tree
get_guard(tree decl)3119 get_guard (tree decl)
3120 {
3121 tree sname;
3122 tree guard;
3123
3124 sname = mangle_guard_variable (decl);
3125 guard = get_global_binding (sname);
3126 if (! guard)
3127 {
3128 tree guard_type;
3129
3130 /* We use a type that is big enough to contain a mutex as well
3131 as an integer counter. */
3132 guard_type = targetm.cxx.guard_type ();
3133 guard = build_decl (DECL_SOURCE_LOCATION (decl),
3134 VAR_DECL, sname, guard_type);
3135
3136 /* The guard should have the same linkage as what it guards. */
3137 TREE_PUBLIC (guard) = TREE_PUBLIC (decl);
3138 TREE_STATIC (guard) = TREE_STATIC (decl);
3139 DECL_COMMON (guard) = DECL_COMMON (decl);
3140 DECL_COMDAT (guard) = DECL_COMDAT (decl);
3141 CP_DECL_THREAD_LOCAL_P (guard) = CP_DECL_THREAD_LOCAL_P (decl);
3142 set_decl_tls_model (guard, DECL_TLS_MODEL (decl));
3143 if (DECL_ONE_ONLY (decl))
3144 make_decl_one_only (guard, cxx_comdat_group (guard));
3145 if (TREE_PUBLIC (decl))
3146 DECL_WEAK (guard) = DECL_WEAK (decl);
3147 DECL_VISIBILITY (guard) = DECL_VISIBILITY (decl);
3148 DECL_VISIBILITY_SPECIFIED (guard) = DECL_VISIBILITY_SPECIFIED (decl);
3149
3150 DECL_ARTIFICIAL (guard) = 1;
3151 DECL_IGNORED_P (guard) = 1;
3152 TREE_USED (guard) = 1;
3153 pushdecl_top_level_and_finish (guard, NULL_TREE);
3154 }
3155 return guard;
3156 }
3157
3158 /* Return an atomic load of src with the appropriate memory model. */
3159
3160 static tree
build_atomic_load_byte(tree src,HOST_WIDE_INT model)3161 build_atomic_load_byte (tree src, HOST_WIDE_INT model)
3162 {
3163 tree ptr_type = build_pointer_type (char_type_node);
3164 tree mem_model = build_int_cst (integer_type_node, model);
3165 tree t, addr, val;
3166 unsigned int size;
3167 int fncode;
3168
3169 size = tree_to_uhwi (TYPE_SIZE_UNIT (char_type_node));
3170
3171 fncode = BUILT_IN_ATOMIC_LOAD_N + exact_log2 (size) + 1;
3172 t = builtin_decl_implicit ((enum built_in_function) fncode);
3173
3174 addr = build1 (ADDR_EXPR, ptr_type, src);
3175 val = build_call_expr (t, 2, addr, mem_model);
3176 return val;
3177 }
3178
3179 /* Return those bits of the GUARD variable that should be set when the
3180 guarded entity is actually initialized. */
3181
3182 static tree
get_guard_bits(tree guard)3183 get_guard_bits (tree guard)
3184 {
3185 if (!targetm.cxx.guard_mask_bit ())
3186 {
3187 /* We only set the first byte of the guard, in order to leave room
3188 for a mutex in the high-order bits. */
3189 guard = build1 (ADDR_EXPR,
3190 build_pointer_type (TREE_TYPE (guard)),
3191 guard);
3192 guard = build1 (NOP_EXPR,
3193 build_pointer_type (char_type_node),
3194 guard);
3195 guard = build1 (INDIRECT_REF, char_type_node, guard);
3196 }
3197
3198 return guard;
3199 }
3200
3201 /* Return an expression which determines whether or not the GUARD
3202 variable has already been initialized. */
3203
3204 tree
get_guard_cond(tree guard,bool thread_safe)3205 get_guard_cond (tree guard, bool thread_safe)
3206 {
3207 tree guard_value;
3208
3209 if (!thread_safe)
3210 guard = get_guard_bits (guard);
3211 else
3212 guard = build_atomic_load_byte (guard, MEMMODEL_ACQUIRE);
3213
3214 /* Mask off all but the low bit. */
3215 if (targetm.cxx.guard_mask_bit ())
3216 {
3217 guard_value = integer_one_node;
3218 if (!same_type_p (TREE_TYPE (guard_value), TREE_TYPE (guard)))
3219 guard_value = fold_convert (TREE_TYPE (guard), guard_value);
3220 guard = cp_build_binary_op (input_location,
3221 BIT_AND_EXPR, guard, guard_value,
3222 tf_warning_or_error);
3223 }
3224
3225 guard_value = integer_zero_node;
3226 if (!same_type_p (TREE_TYPE (guard_value), TREE_TYPE (guard)))
3227 guard_value = fold_convert (TREE_TYPE (guard), guard_value);
3228 return cp_build_binary_op (input_location,
3229 EQ_EXPR, guard, guard_value,
3230 tf_warning_or_error);
3231 }
3232
3233 /* Return an expression which sets the GUARD variable, indicating that
3234 the variable being guarded has been initialized. */
3235
3236 tree
set_guard(tree guard)3237 set_guard (tree guard)
3238 {
3239 tree guard_init;
3240
3241 /* Set the GUARD to one. */
3242 guard = get_guard_bits (guard);
3243 guard_init = integer_one_node;
3244 if (!same_type_p (TREE_TYPE (guard_init), TREE_TYPE (guard)))
3245 guard_init = fold_convert (TREE_TYPE (guard), guard_init);
3246 return cp_build_modify_expr (input_location, guard, NOP_EXPR, guard_init,
3247 tf_warning_or_error);
3248 }
3249
3250 /* Returns true iff we can tell that VAR does not have a dynamic
3251 initializer. */
3252
3253 static bool
var_defined_without_dynamic_init(tree var)3254 var_defined_without_dynamic_init (tree var)
3255 {
3256 /* If it's defined in another TU, we can't tell. */
3257 if (DECL_EXTERNAL (var))
3258 return false;
3259 /* If it has a non-trivial destructor, registering the destructor
3260 counts as dynamic initialization. */
3261 if (TYPE_HAS_NONTRIVIAL_DESTRUCTOR (TREE_TYPE (var)))
3262 return false;
3263 /* If it's in this TU, its initializer has been processed, unless
3264 it's a case of self-initialization, then DECL_INITIALIZED_P is
3265 false while the initializer is handled by finish_id_expression. */
3266 if (!DECL_INITIALIZED_P (var))
3267 return false;
3268 /* If it has no initializer or a constant one, it's not dynamic. */
3269 return (!DECL_NONTRIVIALLY_INITIALIZED_P (var)
3270 || DECL_INITIALIZED_BY_CONSTANT_EXPRESSION_P (var));
3271 }
3272
3273 /* Returns true iff VAR is a variable that needs uses to be
3274 wrapped for possible dynamic initialization. */
3275
3276 static bool
var_needs_tls_wrapper(tree var)3277 var_needs_tls_wrapper (tree var)
3278 {
3279 return (!error_operand_p (var)
3280 && CP_DECL_THREAD_LOCAL_P (var)
3281 && !DECL_GNU_TLS_P (var)
3282 && !DECL_FUNCTION_SCOPE_P (var)
3283 && !var_defined_without_dynamic_init (var));
3284 }
3285
3286 /* Get the FUNCTION_DECL for the shared TLS init function for this
3287 translation unit. */
3288
3289 static tree
get_local_tls_init_fn(void)3290 get_local_tls_init_fn (void)
3291 {
3292 tree sname = get_identifier ("__tls_init");
3293 tree fn = get_global_binding (sname);
3294 if (!fn)
3295 {
3296 fn = build_lang_decl (FUNCTION_DECL, sname,
3297 build_function_type (void_type_node,
3298 void_list_node));
3299 SET_DECL_LANGUAGE (fn, lang_c);
3300 TREE_PUBLIC (fn) = false;
3301 DECL_ARTIFICIAL (fn) = true;
3302 mark_used (fn);
3303 set_global_binding (fn);
3304 }
3305 return fn;
3306 }
3307
3308 /* Get a FUNCTION_DECL for the init function for the thread_local
3309 variable VAR. The init function will be an alias to the function
3310 that initializes all the non-local TLS variables in the translation
3311 unit. The init function is only used by the wrapper function. */
3312
3313 static tree
get_tls_init_fn(tree var)3314 get_tls_init_fn (tree var)
3315 {
3316 /* Only C++11 TLS vars need this init fn. */
3317 if (!var_needs_tls_wrapper (var))
3318 return NULL_TREE;
3319
3320 /* If -fno-extern-tls-init, assume that we don't need to call
3321 a tls init function for a variable defined in another TU. */
3322 if (!flag_extern_tls_init && DECL_EXTERNAL (var))
3323 return NULL_TREE;
3324
3325 /* If the variable is internal, or if we can't generate aliases,
3326 call the local init function directly. */
3327 if (!TREE_PUBLIC (var) || !TARGET_SUPPORTS_ALIASES)
3328 return get_local_tls_init_fn ();
3329
3330 tree sname = mangle_tls_init_fn (var);
3331 tree fn = get_global_binding (sname);
3332 if (!fn)
3333 {
3334 fn = build_lang_decl (FUNCTION_DECL, sname,
3335 build_function_type (void_type_node,
3336 void_list_node));
3337 SET_DECL_LANGUAGE (fn, lang_c);
3338 TREE_PUBLIC (fn) = TREE_PUBLIC (var);
3339 DECL_ARTIFICIAL (fn) = true;
3340 DECL_COMDAT (fn) = DECL_COMDAT (var);
3341 DECL_EXTERNAL (fn) = DECL_EXTERNAL (var);
3342 if (DECL_ONE_ONLY (var))
3343 make_decl_one_only (fn, cxx_comdat_group (fn));
3344 if (TREE_PUBLIC (var))
3345 {
3346 tree obtype = strip_array_types (non_reference (TREE_TYPE (var)));
3347 /* If the variable is defined somewhere else and might have static
3348 initialization, make the init function a weak reference. */
3349 if ((!TYPE_NEEDS_CONSTRUCTING (obtype)
3350 || TYPE_HAS_CONSTEXPR_CTOR (obtype)
3351 || TYPE_HAS_TRIVIAL_DFLT (obtype))
3352 && TYPE_HAS_TRIVIAL_DESTRUCTOR (obtype)
3353 && DECL_EXTERNAL (var))
3354 declare_weak (fn);
3355 else
3356 DECL_WEAK (fn) = DECL_WEAK (var);
3357 }
3358 DECL_VISIBILITY (fn) = DECL_VISIBILITY (var);
3359 DECL_VISIBILITY_SPECIFIED (fn) = DECL_VISIBILITY_SPECIFIED (var);
3360 DECL_DLLIMPORT_P (fn) = DECL_DLLIMPORT_P (var);
3361 DECL_IGNORED_P (fn) = 1;
3362 mark_used (fn);
3363
3364 DECL_BEFRIENDING_CLASSES (fn) = var;
3365
3366 set_global_binding (fn);
3367 }
3368 return fn;
3369 }
3370
3371 /* Get a FUNCTION_DECL for the init wrapper function for the thread_local
3372 variable VAR. The wrapper function calls the init function (if any) for
3373 VAR and then returns a reference to VAR. The wrapper function is used
3374 in place of VAR everywhere VAR is mentioned. */
3375
3376 static tree
get_tls_wrapper_fn(tree var)3377 get_tls_wrapper_fn (tree var)
3378 {
3379 /* Only C++11 TLS vars need this wrapper fn. */
3380 if (!var_needs_tls_wrapper (var))
3381 return NULL_TREE;
3382
3383 tree sname = mangle_tls_wrapper_fn (var);
3384 tree fn = get_global_binding (sname);
3385 if (!fn)
3386 {
3387 /* A named rvalue reference is an lvalue, so the wrapper should
3388 always return an lvalue reference. */
3389 tree type = non_reference (TREE_TYPE (var));
3390 type = build_reference_type (type);
3391 tree fntype = build_function_type (type, void_list_node);
3392 fn = build_lang_decl (FUNCTION_DECL, sname, fntype);
3393 SET_DECL_LANGUAGE (fn, lang_c);
3394 TREE_PUBLIC (fn) = TREE_PUBLIC (var);
3395 DECL_ARTIFICIAL (fn) = true;
3396 DECL_IGNORED_P (fn) = 1;
3397 /* The wrapper is inline and emitted everywhere var is used. */
3398 DECL_DECLARED_INLINE_P (fn) = true;
3399 if (TREE_PUBLIC (var))
3400 {
3401 comdat_linkage (fn);
3402 #ifdef HAVE_GAS_HIDDEN
3403 /* Make the wrapper bind locally; there's no reason to share
3404 the wrapper between multiple shared objects. */
3405 DECL_VISIBILITY (fn) = VISIBILITY_INTERNAL;
3406 DECL_VISIBILITY_SPECIFIED (fn) = true;
3407 #endif
3408 }
3409 if (!TREE_PUBLIC (fn))
3410 DECL_INTERFACE_KNOWN (fn) = true;
3411 mark_used (fn);
3412 note_vague_linkage_fn (fn);
3413
3414 #if 0
3415 /* We want CSE to commonize calls to the wrapper, but marking it as
3416 pure is unsafe since it has side-effects. I guess we need a new
3417 ECF flag even weaker than ECF_PURE. FIXME! */
3418 DECL_PURE_P (fn) = true;
3419 #endif
3420
3421 DECL_BEFRIENDING_CLASSES (fn) = var;
3422
3423 set_global_binding (fn);
3424 }
3425 return fn;
3426 }
3427
3428 /* If EXPR is a thread_local variable that should be wrapped by init
3429 wrapper function, return a call to that function, otherwise return
3430 NULL. */
3431
3432 tree
maybe_get_tls_wrapper_call(tree expr)3433 maybe_get_tls_wrapper_call (tree expr)
3434 {
3435 if (VAR_P (expr)
3436 && !processing_template_decl
3437 && !cp_unevaluated_operand
3438 && CP_DECL_THREAD_LOCAL_P (expr))
3439 if (tree wrap = get_tls_wrapper_fn (expr))
3440 return build_cxx_call (wrap, 0, NULL, tf_warning_or_error);
3441 return NULL;
3442 }
3443
3444 /* At EOF, generate the definition for the TLS wrapper function FN:
3445
3446 T& var_wrapper() {
3447 if (init_fn) init_fn();
3448 return var;
3449 } */
3450
3451 static void
generate_tls_wrapper(tree fn)3452 generate_tls_wrapper (tree fn)
3453 {
3454 tree var = DECL_BEFRIENDING_CLASSES (fn);
3455
3456 start_preparsed_function (fn, NULL_TREE, SF_DEFAULT | SF_PRE_PARSED);
3457 tree body = begin_function_body ();
3458 /* Only call the init fn if there might be one. */
3459 if (tree init_fn = get_tls_init_fn (var))
3460 {
3461 tree if_stmt = NULL_TREE;
3462 /* If init_fn is a weakref, make sure it exists before calling. */
3463 if (lookup_attribute ("weak", DECL_ATTRIBUTES (init_fn)))
3464 {
3465 if_stmt = begin_if_stmt ();
3466 tree addr = cp_build_addr_expr (init_fn, tf_warning_or_error);
3467 tree cond = cp_build_binary_op (DECL_SOURCE_LOCATION (var),
3468 NE_EXPR, addr, nullptr_node,
3469 tf_warning_or_error);
3470 finish_if_stmt_cond (cond, if_stmt);
3471 }
3472 finish_expr_stmt (build_cxx_call
3473 (init_fn, 0, NULL, tf_warning_or_error));
3474 if (if_stmt)
3475 {
3476 finish_then_clause (if_stmt);
3477 finish_if_stmt (if_stmt);
3478 }
3479 }
3480 else
3481 /* If there's no initialization, the wrapper is a constant function. */
3482 TREE_READONLY (fn) = true;
3483 finish_return_stmt (convert_from_reference (var));
3484 finish_function_body (body);
3485 expand_or_defer_fn (finish_function (/*inline_p=*/false));
3486 }
3487
3488 /* Start the process of running a particular set of global constructors
3489 or destructors. Subroutine of do_[cd]tors. Also called from
3490 vtv_start_verification_constructor_init_function. */
3491
3492 static tree
start_objects(int method_type,int initp)3493 start_objects (int method_type, int initp)
3494 {
3495 tree body;
3496 tree fndecl;
3497 char type[14];
3498
3499 /* Make ctor or dtor function. METHOD_TYPE may be 'I' or 'D'. */
3500
3501 if (initp != DEFAULT_INIT_PRIORITY)
3502 {
3503 char joiner;
3504
3505 #ifdef JOINER
3506 joiner = JOINER;
3507 #else
3508 joiner = '_';
3509 #endif
3510
3511 sprintf (type, "sub_%c%c%.5u", method_type, joiner, initp);
3512 }
3513 else
3514 sprintf (type, "sub_%c", method_type);
3515
3516 fndecl = build_lang_decl (FUNCTION_DECL,
3517 get_file_function_name (type),
3518 build_function_type_list (void_type_node,
3519 NULL_TREE));
3520 start_preparsed_function (fndecl, /*attrs=*/NULL_TREE, SF_PRE_PARSED);
3521
3522 TREE_PUBLIC (current_function_decl) = 0;
3523
3524 /* Mark as artificial because it's not explicitly in the user's
3525 source code. */
3526 DECL_ARTIFICIAL (current_function_decl) = 1;
3527
3528 /* Mark this declaration as used to avoid spurious warnings. */
3529 TREE_USED (current_function_decl) = 1;
3530
3531 /* Mark this function as a global constructor or destructor. */
3532 if (method_type == 'I')
3533 DECL_GLOBAL_CTOR_P (current_function_decl) = 1;
3534 else
3535 DECL_GLOBAL_DTOR_P (current_function_decl) = 1;
3536
3537 body = begin_compound_stmt (BCS_FN_BODY);
3538
3539 return body;
3540 }
3541
3542 /* Finish the process of running a particular set of global constructors
3543 or destructors. Subroutine of do_[cd]tors. */
3544
3545 static void
finish_objects(int method_type,int initp,tree body)3546 finish_objects (int method_type, int initp, tree body)
3547 {
3548 tree fn;
3549
3550 /* Finish up. */
3551 finish_compound_stmt (body);
3552 fn = finish_function (/*inline_p=*/false);
3553
3554 if (method_type == 'I')
3555 {
3556 DECL_STATIC_CONSTRUCTOR (fn) = 1;
3557 decl_init_priority_insert (fn, initp);
3558 }
3559 else
3560 {
3561 DECL_STATIC_DESTRUCTOR (fn) = 1;
3562 decl_fini_priority_insert (fn, initp);
3563 }
3564
3565 expand_or_defer_fn (fn);
3566 }
3567
3568 /* The names of the parameters to the function created to handle
3569 initializations and destructions for objects with static storage
3570 duration. */
3571 #define INITIALIZE_P_IDENTIFIER "__initialize_p"
3572 #define PRIORITY_IDENTIFIER "__priority"
3573
3574 /* The name of the function we create to handle initializations and
3575 destructions for objects with static storage duration. */
3576 #define SSDF_IDENTIFIER "__static_initialization_and_destruction"
3577
3578 /* The declaration for the __INITIALIZE_P argument. */
3579 static GTY(()) tree initialize_p_decl;
3580
3581 /* The declaration for the __PRIORITY argument. */
3582 static GTY(()) tree priority_decl;
3583
3584 /* The declaration for the static storage duration function. */
3585 static GTY(()) tree ssdf_decl;
3586
3587 /* All the static storage duration functions created in this
3588 translation unit. */
3589 static GTY(()) vec<tree, va_gc> *ssdf_decls;
3590
3591 /* A map from priority levels to information about that priority
3592 level. There may be many such levels, so efficient lookup is
3593 important. */
3594 static splay_tree priority_info_map;
3595
3596 /* Begins the generation of the function that will handle all
3597 initialization and destruction of objects with static storage
3598 duration. The function generated takes two parameters of type
3599 `int': __INITIALIZE_P and __PRIORITY. If __INITIALIZE_P is
3600 nonzero, it performs initializations. Otherwise, it performs
3601 destructions. It only performs those initializations or
3602 destructions with the indicated __PRIORITY. The generated function
3603 returns no value.
3604
3605 It is assumed that this function will only be called once per
3606 translation unit. */
3607
3608 static tree
start_static_storage_duration_function(unsigned count)3609 start_static_storage_duration_function (unsigned count)
3610 {
3611 tree type;
3612 tree body;
3613 char id[sizeof (SSDF_IDENTIFIER) + 1 /* '\0' */ + 32];
3614
3615 /* Create the identifier for this function. It will be of the form
3616 SSDF_IDENTIFIER_<number>. */
3617 sprintf (id, "%s_%u", SSDF_IDENTIFIER, count);
3618
3619 type = build_function_type_list (void_type_node,
3620 integer_type_node, integer_type_node,
3621 NULL_TREE);
3622
3623 /* Create the FUNCTION_DECL itself. */
3624 ssdf_decl = build_lang_decl (FUNCTION_DECL,
3625 get_identifier (id),
3626 type);
3627 TREE_PUBLIC (ssdf_decl) = 0;
3628 DECL_ARTIFICIAL (ssdf_decl) = 1;
3629
3630 /* Put this function in the list of functions to be called from the
3631 static constructors and destructors. */
3632 if (!ssdf_decls)
3633 {
3634 vec_alloc (ssdf_decls, 32);
3635
3636 /* Take this opportunity to initialize the map from priority
3637 numbers to information about that priority level. */
3638 priority_info_map = splay_tree_new (splay_tree_compare_ints,
3639 /*delete_key_fn=*/0,
3640 /*delete_value_fn=*/
3641 (splay_tree_delete_value_fn)
3642 (void (*) (void)) free);
3643
3644 /* We always need to generate functions for the
3645 DEFAULT_INIT_PRIORITY so enter it now. That way when we walk
3646 priorities later, we'll be sure to find the
3647 DEFAULT_INIT_PRIORITY. */
3648 get_priority_info (DEFAULT_INIT_PRIORITY);
3649 }
3650
3651 vec_safe_push (ssdf_decls, ssdf_decl);
3652
3653 /* Create the argument list. */
3654 initialize_p_decl = cp_build_parm_decl
3655 (ssdf_decl, get_identifier (INITIALIZE_P_IDENTIFIER), integer_type_node);
3656 TREE_USED (initialize_p_decl) = 1;
3657 priority_decl = cp_build_parm_decl
3658 (ssdf_decl, get_identifier (PRIORITY_IDENTIFIER), integer_type_node);
3659 TREE_USED (priority_decl) = 1;
3660
3661 DECL_CHAIN (initialize_p_decl) = priority_decl;
3662 DECL_ARGUMENTS (ssdf_decl) = initialize_p_decl;
3663
3664 /* Put the function in the global scope. */
3665 pushdecl (ssdf_decl);
3666
3667 /* Start the function itself. This is equivalent to declaring the
3668 function as:
3669
3670 static void __ssdf (int __initialize_p, init __priority_p);
3671
3672 It is static because we only need to call this function from the
3673 various constructor and destructor functions for this module. */
3674 start_preparsed_function (ssdf_decl,
3675 /*attrs=*/NULL_TREE,
3676 SF_PRE_PARSED);
3677
3678 /* Set up the scope of the outermost block in the function. */
3679 body = begin_compound_stmt (BCS_FN_BODY);
3680
3681 return body;
3682 }
3683
3684 /* Finish the generation of the function which performs initialization
3685 and destruction of objects with static storage duration. After
3686 this point, no more such objects can be created. */
3687
3688 static void
finish_static_storage_duration_function(tree body)3689 finish_static_storage_duration_function (tree body)
3690 {
3691 /* Close out the function. */
3692 finish_compound_stmt (body);
3693 expand_or_defer_fn (finish_function (/*inline_p=*/false));
3694 }
3695
3696 /* Return the information about the indicated PRIORITY level. If no
3697 code to handle this level has yet been generated, generate the
3698 appropriate prologue. */
3699
3700 static priority_info
get_priority_info(int priority)3701 get_priority_info (int priority)
3702 {
3703 priority_info pi;
3704 splay_tree_node n;
3705
3706 n = splay_tree_lookup (priority_info_map,
3707 (splay_tree_key) priority);
3708 if (!n)
3709 {
3710 /* Create a new priority information structure, and insert it
3711 into the map. */
3712 pi = XNEW (struct priority_info_s);
3713 pi->initializations_p = 0;
3714 pi->destructions_p = 0;
3715 splay_tree_insert (priority_info_map,
3716 (splay_tree_key) priority,
3717 (splay_tree_value) pi);
3718 }
3719 else
3720 pi = (priority_info) n->value;
3721
3722 return pi;
3723 }
3724
3725 /* The effective initialization priority of a DECL. */
3726
3727 #define DECL_EFFECTIVE_INIT_PRIORITY(decl) \
3728 ((!DECL_HAS_INIT_PRIORITY_P (decl) || DECL_INIT_PRIORITY (decl) == 0) \
3729 ? DEFAULT_INIT_PRIORITY : DECL_INIT_PRIORITY (decl))
3730
3731 /* Whether a DECL needs a guard to protect it against multiple
3732 initialization. */
3733
3734 #define NEEDS_GUARD_P(decl) (TREE_PUBLIC (decl) && (DECL_COMMON (decl) \
3735 || DECL_ONE_ONLY (decl) \
3736 || DECL_WEAK (decl)))
3737
3738 /* Called from one_static_initialization_or_destruction(),
3739 via walk_tree.
3740 Walks the initializer list of a global variable and looks for
3741 temporary variables (DECL_NAME() == NULL and DECL_ARTIFICIAL != 0)
3742 and that have their DECL_CONTEXT() == NULL.
3743 For each such temporary variable, set their DECL_CONTEXT() to
3744 the current function. This is necessary because otherwise
3745 some optimizers (enabled by -O2 -fprofile-arcs) might crash
3746 when trying to refer to a temporary variable that does not have
3747 it's DECL_CONTECT() properly set. */
3748 static tree
fix_temporary_vars_context_r(tree * node,int *,void *)3749 fix_temporary_vars_context_r (tree *node,
3750 int * /*unused*/,
3751 void * /*unused1*/)
3752 {
3753 gcc_assert (current_function_decl);
3754
3755 if (TREE_CODE (*node) == BIND_EXPR)
3756 {
3757 tree var;
3758
3759 for (var = BIND_EXPR_VARS (*node); var; var = DECL_CHAIN (var))
3760 if (VAR_P (var)
3761 && !DECL_NAME (var)
3762 && DECL_ARTIFICIAL (var)
3763 && !DECL_CONTEXT (var))
3764 DECL_CONTEXT (var) = current_function_decl;
3765 }
3766
3767 return NULL_TREE;
3768 }
3769
3770 /* Set up to handle the initialization or destruction of DECL. If
3771 INITP is nonzero, we are initializing the variable. Otherwise, we
3772 are destroying it. */
3773
3774 static void
one_static_initialization_or_destruction(tree decl,tree init,bool initp)3775 one_static_initialization_or_destruction (tree decl, tree init, bool initp)
3776 {
3777 tree guard_if_stmt = NULL_TREE;
3778 tree guard;
3779
3780 /* If we are supposed to destruct and there's a trivial destructor,
3781 nothing has to be done. */
3782 if (!initp
3783 && TYPE_HAS_TRIVIAL_DESTRUCTOR (TREE_TYPE (decl)))
3784 return;
3785
3786 /* Trick the compiler into thinking we are at the file and line
3787 where DECL was declared so that error-messages make sense, and so
3788 that the debugger will show somewhat sensible file and line
3789 information. */
3790 input_location = DECL_SOURCE_LOCATION (decl);
3791
3792 /* Make sure temporary variables in the initialiser all have
3793 their DECL_CONTEXT() set to a value different from NULL_TREE.
3794 This can happen when global variables initializers are built.
3795 In that case, the DECL_CONTEXT() of the global variables _AND_ of all
3796 the temporary variables that might have been generated in the
3797 accompanying initializers is NULL_TREE, meaning the variables have been
3798 declared in the global namespace.
3799 What we want to do here is to fix that and make sure the DECL_CONTEXT()
3800 of the temporaries are set to the current function decl. */
3801 cp_walk_tree_without_duplicates (&init,
3802 fix_temporary_vars_context_r,
3803 NULL);
3804
3805 /* Because of:
3806
3807 [class.access.spec]
3808
3809 Access control for implicit calls to the constructors,
3810 the conversion functions, or the destructor called to
3811 create and destroy a static data member is performed as
3812 if these calls appeared in the scope of the member's
3813 class.
3814
3815 we pretend we are in a static member function of the class of
3816 which the DECL is a member. */
3817 if (member_p (decl))
3818 {
3819 DECL_CONTEXT (current_function_decl) = DECL_CONTEXT (decl);
3820 DECL_STATIC_FUNCTION_P (current_function_decl) = 1;
3821 }
3822
3823 /* Assume we don't need a guard. */
3824 guard = NULL_TREE;
3825 /* We need a guard if this is an object with external linkage that
3826 might be initialized in more than one place. (For example, a
3827 static data member of a template, when the data member requires
3828 construction.) */
3829 if (NEEDS_GUARD_P (decl))
3830 {
3831 tree guard_cond;
3832
3833 guard = get_guard (decl);
3834
3835 /* When using __cxa_atexit, we just check the GUARD as we would
3836 for a local static. */
3837 if (flag_use_cxa_atexit)
3838 {
3839 /* When using __cxa_atexit, we never try to destroy
3840 anything from a static destructor. */
3841 gcc_assert (initp);
3842 guard_cond = get_guard_cond (guard, false);
3843 }
3844 /* If we don't have __cxa_atexit, then we will be running
3845 destructors from .fini sections, or their equivalents. So,
3846 we need to know how many times we've tried to initialize this
3847 object. We do initializations only if the GUARD is zero,
3848 i.e., if we are the first to initialize the variable. We do
3849 destructions only if the GUARD is one, i.e., if we are the
3850 last to destroy the variable. */
3851 else if (initp)
3852 guard_cond
3853 = cp_build_binary_op (input_location,
3854 EQ_EXPR,
3855 cp_build_unary_op (PREINCREMENT_EXPR,
3856 guard,
3857 /*noconvert=*/true,
3858 tf_warning_or_error),
3859 integer_one_node,
3860 tf_warning_or_error);
3861 else
3862 guard_cond
3863 = cp_build_binary_op (input_location,
3864 EQ_EXPR,
3865 cp_build_unary_op (PREDECREMENT_EXPR,
3866 guard,
3867 /*noconvert=*/true,
3868 tf_warning_or_error),
3869 integer_zero_node,
3870 tf_warning_or_error);
3871
3872 guard_if_stmt = begin_if_stmt ();
3873 finish_if_stmt_cond (guard_cond, guard_if_stmt);
3874 }
3875
3876
3877 /* If we're using __cxa_atexit, we have not already set the GUARD,
3878 so we must do so now. */
3879 if (guard && initp && flag_use_cxa_atexit)
3880 finish_expr_stmt (set_guard (guard));
3881
3882 /* Perform the initialization or destruction. */
3883 if (initp)
3884 {
3885 if (init)
3886 {
3887 finish_expr_stmt (init);
3888 if (sanitize_flags_p (SANITIZE_ADDRESS, decl))
3889 {
3890 varpool_node *vnode = varpool_node::get (decl);
3891 if (vnode)
3892 vnode->dynamically_initialized = 1;
3893 }
3894 }
3895
3896 /* If we're using __cxa_atexit, register a function that calls the
3897 destructor for the object. */
3898 if (flag_use_cxa_atexit)
3899 finish_expr_stmt (register_dtor_fn (decl));
3900 }
3901 else
3902 finish_expr_stmt (build_cleanup (decl));
3903
3904 /* Finish the guard if-stmt, if necessary. */
3905 if (guard)
3906 {
3907 finish_then_clause (guard_if_stmt);
3908 finish_if_stmt (guard_if_stmt);
3909 }
3910
3911 /* Now that we're done with DECL we don't need to pretend to be a
3912 member of its class any longer. */
3913 DECL_CONTEXT (current_function_decl) = NULL_TREE;
3914 DECL_STATIC_FUNCTION_P (current_function_decl) = 0;
3915 }
3916
3917 /* Generate code to do the initialization or destruction of the decls in VARS,
3918 a TREE_LIST of VAR_DECL with static storage duration.
3919 Whether initialization or destruction is performed is specified by INITP. */
3920
3921 static void
do_static_initialization_or_destruction(tree vars,bool initp)3922 do_static_initialization_or_destruction (tree vars, bool initp)
3923 {
3924 tree node, init_if_stmt, cond;
3925
3926 /* Build the outer if-stmt to check for initialization or destruction. */
3927 init_if_stmt = begin_if_stmt ();
3928 cond = initp ? integer_one_node : integer_zero_node;
3929 cond = cp_build_binary_op (input_location,
3930 EQ_EXPR,
3931 initialize_p_decl,
3932 cond,
3933 tf_warning_or_error);
3934 finish_if_stmt_cond (cond, init_if_stmt);
3935
3936 /* To make sure dynamic construction doesn't access globals from other
3937 compilation units where they might not be yet constructed, for
3938 -fsanitize=address insert __asan_before_dynamic_init call that
3939 prevents access to either all global variables that need construction
3940 in other compilation units, or at least those that haven't been
3941 initialized yet. Variables that need dynamic construction in
3942 the current compilation unit are kept accessible. */
3943 if (initp && (flag_sanitize & SANITIZE_ADDRESS))
3944 finish_expr_stmt (asan_dynamic_init_call (/*after_p=*/false));
3945
3946 node = vars;
3947 do {
3948 tree decl = TREE_VALUE (node);
3949 tree priority_if_stmt;
3950 int priority;
3951 priority_info pi;
3952
3953 /* If we don't need a destructor, there's nothing to do. Avoid
3954 creating a possibly empty if-stmt. */
3955 if (!initp && TYPE_HAS_TRIVIAL_DESTRUCTOR (TREE_TYPE (decl)))
3956 {
3957 node = TREE_CHAIN (node);
3958 continue;
3959 }
3960
3961 /* Remember that we had an initialization or finalization at this
3962 priority. */
3963 priority = DECL_EFFECTIVE_INIT_PRIORITY (decl);
3964 pi = get_priority_info (priority);
3965 if (initp)
3966 pi->initializations_p = 1;
3967 else
3968 pi->destructions_p = 1;
3969
3970 /* Conditionalize this initialization on being in the right priority
3971 and being initializing/finalizing appropriately. */
3972 priority_if_stmt = begin_if_stmt ();
3973 cond = cp_build_binary_op (input_location,
3974 EQ_EXPR,
3975 priority_decl,
3976 build_int_cst (NULL_TREE, priority),
3977 tf_warning_or_error);
3978 finish_if_stmt_cond (cond, priority_if_stmt);
3979
3980 /* Process initializers with same priority. */
3981 for (; node
3982 && DECL_EFFECTIVE_INIT_PRIORITY (TREE_VALUE (node)) == priority;
3983 node = TREE_CHAIN (node))
3984 /* Do one initialization or destruction. */
3985 one_static_initialization_or_destruction (TREE_VALUE (node),
3986 TREE_PURPOSE (node), initp);
3987
3988 /* Finish up the priority if-stmt body. */
3989 finish_then_clause (priority_if_stmt);
3990 finish_if_stmt (priority_if_stmt);
3991
3992 } while (node);
3993
3994 /* Revert what __asan_before_dynamic_init did by calling
3995 __asan_after_dynamic_init. */
3996 if (initp && (flag_sanitize & SANITIZE_ADDRESS))
3997 finish_expr_stmt (asan_dynamic_init_call (/*after_p=*/true));
3998
3999 /* Finish up the init/destruct if-stmt body. */
4000 finish_then_clause (init_if_stmt);
4001 finish_if_stmt (init_if_stmt);
4002 }
4003
4004 /* VARS is a list of variables with static storage duration which may
4005 need initialization and/or finalization. Remove those variables
4006 that don't really need to be initialized or finalized, and return
4007 the resulting list. The order in which the variables appear in
4008 VARS is in reverse order of the order in which they should actually
4009 be initialized. The list we return is in the unreversed order;
4010 i.e., the first variable should be initialized first. */
4011
4012 static tree
prune_vars_needing_no_initialization(tree * vars)4013 prune_vars_needing_no_initialization (tree *vars)
4014 {
4015 tree *var = vars;
4016 tree result = NULL_TREE;
4017
4018 while (*var)
4019 {
4020 tree t = *var;
4021 tree decl = TREE_VALUE (t);
4022 tree init = TREE_PURPOSE (t);
4023
4024 /* Deal gracefully with error. */
4025 if (error_operand_p (decl))
4026 {
4027 var = &TREE_CHAIN (t);
4028 continue;
4029 }
4030
4031 /* The only things that can be initialized are variables. */
4032 gcc_assert (VAR_P (decl));
4033
4034 /* If this object is not defined, we don't need to do anything
4035 here. */
4036 if (DECL_EXTERNAL (decl))
4037 {
4038 var = &TREE_CHAIN (t);
4039 continue;
4040 }
4041
4042 /* Also, if the initializer already contains errors, we can bail
4043 out now. */
4044 if (init && TREE_CODE (init) == TREE_LIST
4045 && value_member (error_mark_node, init))
4046 {
4047 var = &TREE_CHAIN (t);
4048 continue;
4049 }
4050
4051 /* This variable is going to need initialization and/or
4052 finalization, so we add it to the list. */
4053 *var = TREE_CHAIN (t);
4054 TREE_CHAIN (t) = result;
4055 result = t;
4056 }
4057
4058 return result;
4059 }
4060
4061 /* Make sure we have told the back end about all the variables in
4062 VARS. */
4063
4064 static void
write_out_vars(tree vars)4065 write_out_vars (tree vars)
4066 {
4067 tree v;
4068
4069 for (v = vars; v; v = TREE_CHAIN (v))
4070 {
4071 tree var = TREE_VALUE (v);
4072 if (!var_finalized_p (var))
4073 {
4074 import_export_decl (var);
4075 rest_of_decl_compilation (var, 1, 1);
4076 }
4077 }
4078 }
4079
4080 /* Generate a static constructor (if CONSTRUCTOR_P) or destructor
4081 (otherwise) that will initialize all global objects with static
4082 storage duration having the indicated PRIORITY. */
4083
4084 static void
generate_ctor_or_dtor_function(bool constructor_p,int priority,location_t * locus)4085 generate_ctor_or_dtor_function (bool constructor_p, int priority,
4086 location_t *locus)
4087 {
4088 char function_key;
4089 tree fndecl;
4090 tree body;
4091 size_t i;
4092
4093 input_location = *locus;
4094 /* ??? */
4095 /* Was: locus->line++; */
4096
4097 /* We use `I' to indicate initialization and `D' to indicate
4098 destruction. */
4099 function_key = constructor_p ? 'I' : 'D';
4100
4101 /* We emit the function lazily, to avoid generating empty
4102 global constructors and destructors. */
4103 body = NULL_TREE;
4104
4105 /* For Objective-C++, we may need to initialize metadata found in this module.
4106 This must be done _before_ any other static initializations. */
4107 if (c_dialect_objc () && (priority == DEFAULT_INIT_PRIORITY)
4108 && constructor_p && objc_static_init_needed_p ())
4109 {
4110 body = start_objects (function_key, priority);
4111 objc_generate_static_init_call (NULL_TREE);
4112 }
4113
4114 /* Call the static storage duration function with appropriate
4115 arguments. */
4116 FOR_EACH_VEC_SAFE_ELT (ssdf_decls, i, fndecl)
4117 {
4118 /* Calls to pure or const functions will expand to nothing. */
4119 if (! (flags_from_decl_or_type (fndecl) & (ECF_CONST | ECF_PURE)))
4120 {
4121 tree call;
4122
4123 if (! body)
4124 body = start_objects (function_key, priority);
4125
4126 call = cp_build_function_call_nary (fndecl, tf_warning_or_error,
4127 build_int_cst (NULL_TREE,
4128 constructor_p),
4129 build_int_cst (NULL_TREE,
4130 priority),
4131 NULL_TREE);
4132 finish_expr_stmt (call);
4133 }
4134 }
4135
4136 /* Close out the function. */
4137 if (body)
4138 finish_objects (function_key, priority, body);
4139 }
4140
4141 /* Generate constructor and destructor functions for the priority
4142 indicated by N. */
4143
4144 static int
generate_ctor_and_dtor_functions_for_priority(splay_tree_node n,void * data)4145 generate_ctor_and_dtor_functions_for_priority (splay_tree_node n, void * data)
4146 {
4147 location_t *locus = (location_t *) data;
4148 int priority = (int) n->key;
4149 priority_info pi = (priority_info) n->value;
4150
4151 /* Generate the functions themselves, but only if they are really
4152 needed. */
4153 if (pi->initializations_p)
4154 generate_ctor_or_dtor_function (/*constructor_p=*/true, priority, locus);
4155 if (pi->destructions_p)
4156 generate_ctor_or_dtor_function (/*constructor_p=*/false, priority, locus);
4157
4158 /* Keep iterating. */
4159 return 0;
4160 }
4161
4162 /* Return C++ property of T, based on given operation OP. */
4163
4164 static int
cpp_check(tree t,cpp_operation op)4165 cpp_check (tree t, cpp_operation op)
4166 {
4167 switch (op)
4168 {
4169 case HAS_DEPENDENT_TEMPLATE_ARGS:
4170 {
4171 tree ti = CLASSTYPE_TEMPLATE_INFO (t);
4172 if (!ti)
4173 return 0;
4174 ++processing_template_decl;
4175 const bool dep = any_dependent_template_arguments_p (TI_ARGS (ti));
4176 --processing_template_decl;
4177 return dep;
4178 }
4179 case IS_ABSTRACT:
4180 return DECL_PURE_VIRTUAL_P (t);
4181 case IS_CONSTRUCTOR:
4182 return DECL_CONSTRUCTOR_P (t);
4183 case IS_DESTRUCTOR:
4184 return DECL_DESTRUCTOR_P (t);
4185 case IS_COPY_CONSTRUCTOR:
4186 return DECL_COPY_CONSTRUCTOR_P (t);
4187 case IS_MOVE_CONSTRUCTOR:
4188 return DECL_MOVE_CONSTRUCTOR_P (t);
4189 case IS_TEMPLATE:
4190 return TREE_CODE (t) == TEMPLATE_DECL;
4191 case IS_TRIVIAL:
4192 return trivial_type_p (t);
4193 default:
4194 return 0;
4195 }
4196 }
4197
4198 /* Collect source file references recursively, starting from NAMESPC. */
4199
4200 static void
collect_source_refs(tree namespc)4201 collect_source_refs (tree namespc)
4202 {
4203 /* Iterate over names in this name space. */
4204 for (tree t = NAMESPACE_LEVEL (namespc)->names; t; t = TREE_CHAIN (t))
4205 if (DECL_IS_BUILTIN (t))
4206 ;
4207 else if (TREE_CODE (t) == NAMESPACE_DECL && !DECL_NAMESPACE_ALIAS (t))
4208 collect_source_refs (t);
4209 else
4210 collect_source_ref (DECL_SOURCE_FILE (t));
4211 }
4212
4213 /* Collect decls relevant to SOURCE_FILE from all namespaces recursively,
4214 starting from NAMESPC. */
4215
4216 static void
collect_ada_namespace(tree namespc,const char * source_file)4217 collect_ada_namespace (tree namespc, const char *source_file)
4218 {
4219 tree decl = NAMESPACE_LEVEL (namespc)->names;
4220
4221 /* Collect decls from this namespace. This will skip
4222 NAMESPACE_DECLs (both aliases and regular, it cannot tell). */
4223 collect_ada_nodes (decl, source_file);
4224
4225 /* Now scan for namespace children, and dump them. */
4226 for (; decl; decl = TREE_CHAIN (decl))
4227 if (TREE_CODE (decl) == NAMESPACE_DECL && !DECL_NAMESPACE_ALIAS (decl))
4228 collect_ada_namespace (decl, source_file);
4229 }
4230
4231 /* Returns true iff there is a definition available for variable or
4232 function DECL. */
4233
4234 bool
decl_defined_p(tree decl)4235 decl_defined_p (tree decl)
4236 {
4237 if (TREE_CODE (decl) == FUNCTION_DECL)
4238 return (DECL_INITIAL (decl) != NULL_TREE
4239 /* A pending instantiation of a friend temploid is defined. */
4240 || (DECL_FRIEND_PSEUDO_TEMPLATE_INSTANTIATION (decl)
4241 && DECL_INITIAL (DECL_TEMPLATE_RESULT
4242 (DECL_TI_TEMPLATE (decl)))));
4243 else
4244 {
4245 gcc_assert (VAR_P (decl));
4246 return !DECL_EXTERNAL (decl);
4247 }
4248 }
4249
4250 /* Nonzero for a VAR_DECL whose value can be used in a constant expression.
4251
4252 [expr.const]
4253
4254 An integral constant-expression can only involve ... const
4255 variables of integral or enumeration types initialized with
4256 constant expressions ...
4257
4258 C++0x also allows constexpr variables and temporaries initialized
4259 with constant expressions. We handle the former here, but the latter
4260 are just folded away in cxx_eval_constant_expression.
4261
4262 The standard does not require that the expression be non-volatile.
4263 G++ implements the proposed correction in DR 457. */
4264
4265 bool
decl_constant_var_p(tree decl)4266 decl_constant_var_p (tree decl)
4267 {
4268 if (!decl_maybe_constant_var_p (decl))
4269 return false;
4270
4271 /* We don't know if a template static data member is initialized with
4272 a constant expression until we instantiate its initializer. Even
4273 in the case of a constexpr variable, we can't treat it as a
4274 constant until its initializer is complete in case it's used in
4275 its own initializer. */
4276 maybe_instantiate_decl (decl);
4277 return DECL_INITIALIZED_BY_CONSTANT_EXPRESSION_P (decl);
4278 }
4279
4280 /* Returns true if DECL could be a symbolic constant variable, depending on
4281 its initializer. */
4282
4283 bool
decl_maybe_constant_var_p(tree decl)4284 decl_maybe_constant_var_p (tree decl)
4285 {
4286 tree type = TREE_TYPE (decl);
4287 if (!VAR_P (decl))
4288 return false;
4289 if (DECL_DECLARED_CONSTEXPR_P (decl))
4290 return true;
4291 if (DECL_HAS_VALUE_EXPR_P (decl))
4292 /* A proxy isn't constant. */
4293 return false;
4294 if (TREE_CODE (type) == REFERENCE_TYPE)
4295 /* References can be constant. */;
4296 else if (CP_TYPE_CONST_NON_VOLATILE_P (type)
4297 && INTEGRAL_OR_ENUMERATION_TYPE_P (type))
4298 /* And const integers. */;
4299 else
4300 return false;
4301
4302 if (DECL_INITIAL (decl)
4303 && !DECL_INITIALIZED_BY_CONSTANT_EXPRESSION_P (decl))
4304 /* We know the initializer, and it isn't constant. */
4305 return false;
4306 else
4307 return true;
4308 }
4309
4310 /* Complain that DECL uses a type with no linkage. In C++98 mode this is
4311 called from grokfndecl and grokvardecl; in all modes it is called from
4312 cp_write_global_declarations. */
4313
4314 void
no_linkage_error(tree decl)4315 no_linkage_error (tree decl)
4316 {
4317 if (cxx_dialect >= cxx11 && decl_defined_p (decl))
4318 /* In C++11 it's ok if the decl is defined. */
4319 return;
4320 tree t = no_linkage_check (TREE_TYPE (decl), /*relaxed_p=*/false);
4321 if (t == NULL_TREE)
4322 /* The type that got us on no_linkage_decls must have gotten a name for
4323 linkage purposes. */;
4324 else if (CLASS_TYPE_P (t) && TYPE_BEING_DEFINED (t))
4325 /* The type might end up having a typedef name for linkage purposes. */
4326 vec_safe_push (no_linkage_decls, decl);
4327 else if (TYPE_UNNAMED_P (t))
4328 {
4329 bool d = false;
4330 if (cxx_dialect >= cxx11)
4331 d = permerror (DECL_SOURCE_LOCATION (decl), "%q#D, declared using "
4332 "unnamed type, is used but never defined", decl);
4333 else if (DECL_EXTERN_C_P (decl))
4334 /* Allow this; it's pretty common in C. */;
4335 else if (VAR_P (decl))
4336 /* DRs 132, 319 and 389 seem to indicate types with
4337 no linkage can only be used to declare extern "C"
4338 entities. Since it's not always an error in the
4339 ISO C++ 90 Standard, we only issue a warning. */
4340 d = warning_at (DECL_SOURCE_LOCATION (decl), 0, "unnamed type "
4341 "with no linkage used to declare variable %q#D with "
4342 "linkage", decl);
4343 else
4344 d = permerror (DECL_SOURCE_LOCATION (decl), "unnamed type with no "
4345 "linkage used to declare function %q#D with linkage",
4346 decl);
4347 if (d && is_typedef_decl (TYPE_NAME (t)))
4348 inform (DECL_SOURCE_LOCATION (TYPE_NAME (t)), "%q#D does not refer "
4349 "to the unqualified type, so it is not used for linkage",
4350 TYPE_NAME (t));
4351 }
4352 else if (cxx_dialect >= cxx11)
4353 {
4354 if (VAR_P (decl) || !DECL_PURE_VIRTUAL_P (decl))
4355 permerror (DECL_SOURCE_LOCATION (decl),
4356 "%q#D, declared using local type "
4357 "%qT, is used but never defined", decl, t);
4358 }
4359 else if (VAR_P (decl))
4360 warning_at (DECL_SOURCE_LOCATION (decl), 0, "type %qT with no linkage "
4361 "used to declare variable %q#D with linkage", t, decl);
4362 else
4363 permerror (DECL_SOURCE_LOCATION (decl), "type %qT with no linkage used "
4364 "to declare function %q#D with linkage", t, decl);
4365 }
4366
4367 /* Collect declarations from all namespaces relevant to SOURCE_FILE. */
4368
4369 static void
collect_all_refs(const char * source_file)4370 collect_all_refs (const char *source_file)
4371 {
4372 collect_ada_namespace (global_namespace, source_file);
4373 }
4374
4375 /* Clear DECL_EXTERNAL for NODE. */
4376
4377 static bool
clear_decl_external(struct cgraph_node * node,void *)4378 clear_decl_external (struct cgraph_node *node, void * /*data*/)
4379 {
4380 DECL_EXTERNAL (node->decl) = 0;
4381 return false;
4382 }
4383
4384 /* Build up the function to run dynamic initializers for thread_local
4385 variables in this translation unit and alias the init functions for the
4386 individual variables to it. */
4387
4388 static void
handle_tls_init(void)4389 handle_tls_init (void)
4390 {
4391 tree vars = prune_vars_needing_no_initialization (&tls_aggregates);
4392 if (vars == NULL_TREE)
4393 return;
4394
4395 location_t loc = DECL_SOURCE_LOCATION (TREE_VALUE (vars));
4396
4397 write_out_vars (vars);
4398
4399 tree guard = build_decl (loc, VAR_DECL, get_identifier ("__tls_guard"),
4400 boolean_type_node);
4401 TREE_PUBLIC (guard) = false;
4402 TREE_STATIC (guard) = true;
4403 DECL_ARTIFICIAL (guard) = true;
4404 DECL_IGNORED_P (guard) = true;
4405 TREE_USED (guard) = true;
4406 CP_DECL_THREAD_LOCAL_P (guard) = true;
4407 set_decl_tls_model (guard, decl_default_tls_model (guard));
4408 pushdecl_top_level_and_finish (guard, NULL_TREE);
4409
4410 tree fn = get_local_tls_init_fn ();
4411 start_preparsed_function (fn, NULL_TREE, SF_PRE_PARSED);
4412 tree body = begin_function_body ();
4413 tree if_stmt = begin_if_stmt ();
4414 tree cond = cp_build_unary_op (TRUTH_NOT_EXPR, guard, false,
4415 tf_warning_or_error);
4416 finish_if_stmt_cond (cond, if_stmt);
4417 finish_expr_stmt (cp_build_modify_expr (loc, guard, NOP_EXPR,
4418 boolean_true_node,
4419 tf_warning_or_error));
4420 for (; vars; vars = TREE_CHAIN (vars))
4421 {
4422 tree var = TREE_VALUE (vars);
4423 tree init = TREE_PURPOSE (vars);
4424 one_static_initialization_or_destruction (var, init, true);
4425
4426 /* Output init aliases even with -fno-extern-tls-init. */
4427 if (TARGET_SUPPORTS_ALIASES && TREE_PUBLIC (var))
4428 {
4429 tree single_init_fn = get_tls_init_fn (var);
4430 if (single_init_fn == NULL_TREE)
4431 continue;
4432 cgraph_node *alias
4433 = cgraph_node::get_create (fn)->create_same_body_alias
4434 (single_init_fn, fn);
4435 gcc_assert (alias != NULL);
4436 }
4437 }
4438
4439 finish_then_clause (if_stmt);
4440 finish_if_stmt (if_stmt);
4441 finish_function_body (body);
4442 expand_or_defer_fn (finish_function (/*inline_p=*/false));
4443 }
4444
4445 /* We're at the end of compilation, so generate any mangling aliases that
4446 we've been saving up, if DECL is going to be output and ID2 isn't
4447 already taken by another declaration. */
4448
4449 static void
generate_mangling_alias(tree decl,tree id2)4450 generate_mangling_alias (tree decl, tree id2)
4451 {
4452 struct cgraph_node *n = NULL;
4453
4454 if (TREE_CODE (decl) == FUNCTION_DECL)
4455 {
4456 n = cgraph_node::get (decl);
4457 if (!n)
4458 /* Don't create an alias to an unreferenced function. */
4459 return;
4460 }
4461
4462 tree *slot
4463 = mangled_decls->find_slot_with_hash (id2, IDENTIFIER_HASH_VALUE (id2),
4464 INSERT);
4465
4466 /* If there's a declaration already using this mangled name,
4467 don't create a compatibility alias that conflicts. */
4468 if (*slot)
4469 return;
4470
4471 tree alias = make_alias_for (decl, id2);
4472 *slot = alias;
4473
4474 DECL_IGNORED_P (alias) = 1;
4475 TREE_PUBLIC (alias) = TREE_PUBLIC (decl);
4476 DECL_VISIBILITY (alias) = DECL_VISIBILITY (decl);
4477 if (vague_linkage_p (decl))
4478 DECL_WEAK (alias) = 1;
4479
4480 if (n)
4481 n->create_same_body_alias (alias, decl);
4482 else
4483 varpool_node::create_extra_name_alias (alias, decl);
4484 }
4485
4486 /* Note that we might want to emit an alias with the symbol ID2 for DECL at
4487 the end of translation, for compatibility across bugs in the mangling
4488 implementation. */
4489
4490 void
note_mangling_alias(tree decl,tree id2)4491 note_mangling_alias (tree decl, tree id2)
4492 {
4493 if (TARGET_SUPPORTS_ALIASES)
4494 {
4495 if (!defer_mangling_aliases)
4496 generate_mangling_alias (decl, id2);
4497 else
4498 {
4499 vec_safe_push (mangling_aliases, decl);
4500 vec_safe_push (mangling_aliases, id2);
4501 }
4502 }
4503 }
4504
4505 /* Emit all mangling aliases that were deferred up to this point. */
4506
4507 void
generate_mangling_aliases()4508 generate_mangling_aliases ()
4509 {
4510 while (!vec_safe_is_empty (mangling_aliases))
4511 {
4512 tree id2 = mangling_aliases->pop();
4513 tree decl = mangling_aliases->pop();
4514 generate_mangling_alias (decl, id2);
4515 }
4516 defer_mangling_aliases = false;
4517 }
4518
4519 /* Record a mangling of DECL, whose DECL_ASSEMBLER_NAME has just been
4520 set. NEED_WARNING is true if we must warn about collisions. We do
4521 this to spot changes in mangling that may require compatibility
4522 aliases. */
4523
4524 void
record_mangling(tree decl,bool need_warning)4525 record_mangling (tree decl, bool need_warning)
4526 {
4527 if (!mangled_decls)
4528 mangled_decls = hash_table<mangled_decl_hash>::create_ggc (499);
4529
4530 gcc_checking_assert (DECL_ASSEMBLER_NAME_SET_P (decl));
4531 tree id = DECL_ASSEMBLER_NAME_RAW (decl);
4532 tree *slot
4533 = mangled_decls->find_slot_with_hash (id, IDENTIFIER_HASH_VALUE (id),
4534 INSERT);
4535
4536 /* If this is already an alias, remove the alias, because the real
4537 decl takes precedence. */
4538 if (*slot && DECL_ARTIFICIAL (*slot) && DECL_IGNORED_P (*slot))
4539 if (symtab_node *n = symtab_node::get (*slot))
4540 if (n->cpp_implicit_alias)
4541 {
4542 n->remove ();
4543 *slot = NULL_TREE;
4544 }
4545
4546 if (!*slot)
4547 *slot = decl;
4548 else if (need_warning)
4549 {
4550 error_at (DECL_SOURCE_LOCATION (decl),
4551 "mangling of %q#D as %qE conflicts with a previous mangle",
4552 decl, id);
4553 inform (DECL_SOURCE_LOCATION (*slot),
4554 "previous mangling %q#D", *slot);
4555 inform (DECL_SOURCE_LOCATION (decl),
4556 "a later -fabi-version= (or =0)"
4557 " avoids this error with a change in mangling");
4558 *slot = decl;
4559 }
4560 }
4561
4562 /* The mangled name of DECL is being forcibly changed to NAME. Remove
4563 any existing knowledge of DECL's mangled name meaning DECL. */
4564
4565 void
overwrite_mangling(tree decl,tree name)4566 overwrite_mangling (tree decl, tree name)
4567 {
4568 if (tree id = DECL_ASSEMBLER_NAME_RAW (decl))
4569 if ((TREE_CODE (decl) == VAR_DECL
4570 || TREE_CODE (decl) == FUNCTION_DECL)
4571 && mangled_decls)
4572 if (tree *slot
4573 = mangled_decls->find_slot_with_hash (id, IDENTIFIER_HASH_VALUE (id),
4574 NO_INSERT))
4575 if (*slot == decl)
4576 {
4577 mangled_decls->clear_slot (slot);
4578
4579 /* If this is an alias, remove it from the symbol table. */
4580 if (DECL_ARTIFICIAL (decl) && DECL_IGNORED_P (decl))
4581 if (symtab_node *n = symtab_node::get (decl))
4582 if (n->cpp_implicit_alias)
4583 n->remove ();
4584 }
4585
4586 DECL_ASSEMBLER_NAME_RAW (decl) = name;
4587 }
4588
4589 /* The entire file is now complete. If requested, dump everything
4590 to a file. */
4591
4592 static void
dump_tu(void)4593 dump_tu (void)
4594 {
4595 dump_flags_t flags;
4596 if (FILE *stream = dump_begin (raw_dump_id, &flags))
4597 {
4598 dump_node (global_namespace, flags & ~TDF_SLIM, stream);
4599 dump_end (raw_dump_id, stream);
4600 }
4601 }
4602
4603 static location_t locus_at_end_of_parsing;
4604
4605 /* Check the deallocation functions for CODE to see if we want to warn that
4606 only one was defined. */
4607
4608 static void
maybe_warn_sized_delete(enum tree_code code)4609 maybe_warn_sized_delete (enum tree_code code)
4610 {
4611 tree sized = NULL_TREE;
4612 tree unsized = NULL_TREE;
4613
4614 for (ovl_iterator iter (get_global_binding (ovl_op_identifier (false, code)));
4615 iter; ++iter)
4616 {
4617 tree fn = *iter;
4618 /* We're only interested in usual deallocation functions. */
4619 if (!usual_deallocation_fn_p (fn))
4620 continue;
4621 if (FUNCTION_ARG_CHAIN (fn) == void_list_node)
4622 unsized = fn;
4623 else
4624 sized = fn;
4625 }
4626 if (DECL_INITIAL (unsized) && !DECL_INITIAL (sized))
4627 warning_at (DECL_SOURCE_LOCATION (unsized), OPT_Wsized_deallocation,
4628 "the program should also define %qD", sized);
4629 else if (!DECL_INITIAL (unsized) && DECL_INITIAL (sized))
4630 warning_at (DECL_SOURCE_LOCATION (sized), OPT_Wsized_deallocation,
4631 "the program should also define %qD", unsized);
4632 }
4633
4634 /* Check the global deallocation functions to see if we want to warn about
4635 defining unsized without sized (or vice versa). */
4636
4637 static void
maybe_warn_sized_delete()4638 maybe_warn_sized_delete ()
4639 {
4640 if (!flag_sized_deallocation || !warn_sized_deallocation)
4641 return;
4642 maybe_warn_sized_delete (DELETE_EXPR);
4643 maybe_warn_sized_delete (VEC_DELETE_EXPR);
4644 }
4645
4646 /* Earlier we left PTRMEM_CST in variable initializers alone so that we could
4647 look them up when evaluating non-type template parameters. Now we need to
4648 lower them to something the back end can understand. */
4649
4650 static void
lower_var_init()4651 lower_var_init ()
4652 {
4653 varpool_node *node;
4654 FOR_EACH_VARIABLE (node)
4655 {
4656 tree d = node->decl;
4657 if (tree init = DECL_INITIAL (d))
4658 DECL_INITIAL (d) = cplus_expand_constant (init);
4659 }
4660 }
4661
4662 /* This routine is called at the end of compilation.
4663 Its job is to create all the code needed to initialize and
4664 destroy the global aggregates. We do the destruction
4665 first, since that way we only need to reverse the decls once. */
4666
4667 void
c_parse_final_cleanups(void)4668 c_parse_final_cleanups (void)
4669 {
4670 tree vars;
4671 bool reconsider;
4672 size_t i;
4673 unsigned ssdf_count = 0;
4674 int retries = 0;
4675 tree decl;
4676
4677 locus_at_end_of_parsing = input_location;
4678 at_eof = 1;
4679
4680 /* Bad parse errors. Just forget about it. */
4681 if (! global_bindings_p () || current_class_type
4682 || !vec_safe_is_empty (decl_namespace_list))
4683 return;
4684
4685 /* This is the point to write out a PCH if we're doing that.
4686 In that case we do not want to do anything else. */
4687 if (pch_file)
4688 {
4689 /* Mangle all symbols at PCH creation time. */
4690 symtab_node *node;
4691 FOR_EACH_SYMBOL (node)
4692 if (! is_a <varpool_node *> (node)
4693 || ! DECL_HARD_REGISTER (node->decl))
4694 DECL_ASSEMBLER_NAME (node->decl);
4695 c_common_write_pch ();
4696 dump_tu ();
4697 /* Ensure even the callers don't try to finalize the CU. */
4698 flag_syntax_only = 1;
4699 return;
4700 }
4701
4702 timevar_stop (TV_PHASE_PARSING);
4703 timevar_start (TV_PHASE_DEFERRED);
4704
4705 symtab->process_same_body_aliases ();
4706
4707 /* Handle -fdump-ada-spec[-slim] */
4708 if (flag_dump_ada_spec || flag_dump_ada_spec_slim)
4709 {
4710 if (flag_dump_ada_spec_slim)
4711 collect_source_ref (main_input_filename);
4712 else
4713 collect_source_refs (global_namespace);
4714
4715 dump_ada_specs (collect_all_refs, cpp_check);
4716 }
4717
4718 /* FIXME - huh? was input_line -= 1;*/
4719
4720 /* We now have to write out all the stuff we put off writing out.
4721 These include:
4722
4723 o Template specializations that we have not yet instantiated,
4724 but which are needed.
4725 o Initialization and destruction for non-local objects with
4726 static storage duration. (Local objects with static storage
4727 duration are initialized when their scope is first entered,
4728 and are cleaned up via atexit.)
4729 o Virtual function tables.
4730
4731 All of these may cause others to be needed. For example,
4732 instantiating one function may cause another to be needed, and
4733 generating the initializer for an object may cause templates to be
4734 instantiated, etc., etc. */
4735
4736 emit_support_tinfos ();
4737
4738 do
4739 {
4740 tree t;
4741 tree decl;
4742
4743 reconsider = false;
4744
4745 /* If there are templates that we've put off instantiating, do
4746 them now. */
4747 instantiate_pending_templates (retries);
4748 ggc_collect ();
4749
4750 /* Write out virtual tables as required. Writing out the
4751 virtual table for a template class may cause the
4752 instantiation of members of that class. If we write out
4753 vtables then we remove the class from our list so we don't
4754 have to look at it again. */
4755 for (i = keyed_classes->length ();
4756 keyed_classes->iterate (--i, &t);)
4757 if (maybe_emit_vtables (t))
4758 {
4759 reconsider = true;
4760 keyed_classes->unordered_remove (i);
4761 }
4762 /* The input_location may have been changed during marking of
4763 vtable entries. */
4764 input_location = locus_at_end_of_parsing;
4765
4766 /* Write out needed type info variables. We have to be careful
4767 looping through unemitted decls, because emit_tinfo_decl may
4768 cause other variables to be needed. New elements will be
4769 appended, and we remove from the vector those that actually
4770 get emitted. */
4771 for (i = unemitted_tinfo_decls->length ();
4772 unemitted_tinfo_decls->iterate (--i, &t);)
4773 if (emit_tinfo_decl (t))
4774 {
4775 reconsider = true;
4776 unemitted_tinfo_decls->unordered_remove (i);
4777 }
4778
4779 /* The list of objects with static storage duration is built up
4780 in reverse order. We clear STATIC_AGGREGATES so that any new
4781 aggregates added during the initialization of these will be
4782 initialized in the correct order when we next come around the
4783 loop. */
4784 vars = prune_vars_needing_no_initialization (&static_aggregates);
4785
4786 if (vars)
4787 {
4788 /* We need to start a new initialization function each time
4789 through the loop. That's because we need to know which
4790 vtables have been referenced, and TREE_SYMBOL_REFERENCED
4791 isn't computed until a function is finished, and written
4792 out. That's a deficiency in the back end. When this is
4793 fixed, these initialization functions could all become
4794 inline, with resulting performance improvements. */
4795 tree ssdf_body;
4796
4797 /* Set the line and file, so that it is obviously not from
4798 the source file. */
4799 input_location = locus_at_end_of_parsing;
4800 ssdf_body = start_static_storage_duration_function (ssdf_count);
4801
4802 /* Make sure the back end knows about all the variables. */
4803 write_out_vars (vars);
4804
4805 /* First generate code to do all the initializations. */
4806 if (vars)
4807 do_static_initialization_or_destruction (vars, /*initp=*/true);
4808
4809 /* Then, generate code to do all the destructions. Do these
4810 in reverse order so that the most recently constructed
4811 variable is the first destroyed. If we're using
4812 __cxa_atexit, then we don't need to do this; functions
4813 were registered at initialization time to destroy the
4814 local statics. */
4815 if (!flag_use_cxa_atexit && vars)
4816 {
4817 vars = nreverse (vars);
4818 do_static_initialization_or_destruction (vars, /*initp=*/false);
4819 }
4820 else
4821 vars = NULL_TREE;
4822
4823 /* Finish up the static storage duration function for this
4824 round. */
4825 input_location = locus_at_end_of_parsing;
4826 finish_static_storage_duration_function (ssdf_body);
4827
4828 /* All those initializations and finalizations might cause
4829 us to need more inline functions, more template
4830 instantiations, etc. */
4831 reconsider = true;
4832 ssdf_count++;
4833 /* ??? was: locus_at_end_of_parsing.line++; */
4834 }
4835
4836 /* Now do the same for thread_local variables. */
4837 handle_tls_init ();
4838
4839 /* Go through the set of inline functions whose bodies have not
4840 been emitted yet. If out-of-line copies of these functions
4841 are required, emit them. */
4842 FOR_EACH_VEC_SAFE_ELT (deferred_fns, i, decl)
4843 {
4844 /* Does it need synthesizing? */
4845 if (DECL_DEFAULTED_FN (decl) && ! DECL_INITIAL (decl)
4846 && (! DECL_REALLY_EXTERN (decl) || possibly_inlined_p (decl)))
4847 {
4848 /* Even though we're already at the top-level, we push
4849 there again. That way, when we pop back a few lines
4850 hence, all of our state is restored. Otherwise,
4851 finish_function doesn't clean things up, and we end
4852 up with CURRENT_FUNCTION_DECL set. */
4853 push_to_top_level ();
4854 /* The decl's location will mark where it was first
4855 needed. Save that so synthesize method can indicate
4856 where it was needed from, in case of error */
4857 input_location = DECL_SOURCE_LOCATION (decl);
4858 synthesize_method (decl);
4859 pop_from_top_level ();
4860 reconsider = true;
4861 }
4862
4863 if (!DECL_INITIAL (decl) && decl_tls_wrapper_p (decl))
4864 generate_tls_wrapper (decl);
4865
4866 if (!DECL_SAVED_TREE (decl))
4867 continue;
4868
4869 cgraph_node *node = cgraph_node::get_create (decl);
4870
4871 /* We lie to the back end, pretending that some functions
4872 are not defined when they really are. This keeps these
4873 functions from being put out unnecessarily. But, we must
4874 stop lying when the functions are referenced, or if they
4875 are not comdat since they need to be put out now. If
4876 DECL_INTERFACE_KNOWN, then we have already set
4877 DECL_EXTERNAL appropriately, so there's no need to check
4878 again, and we do not want to clear DECL_EXTERNAL if a
4879 previous call to import_export_decl set it.
4880
4881 This is done in a separate for cycle, because if some
4882 deferred function is contained in another deferred
4883 function later in deferred_fns varray,
4884 rest_of_compilation would skip this function and we
4885 really cannot expand the same function twice. */
4886 import_export_decl (decl);
4887 if (DECL_NOT_REALLY_EXTERN (decl)
4888 && DECL_INITIAL (decl)
4889 && decl_needed_p (decl))
4890 {
4891 if (node->cpp_implicit_alias)
4892 node = node->get_alias_target ();
4893
4894 node->call_for_symbol_thunks_and_aliases (clear_decl_external,
4895 NULL, true);
4896 /* If we mark !DECL_EXTERNAL one of the symbols in some comdat
4897 group, we need to mark all symbols in the same comdat group
4898 that way. */
4899 if (node->same_comdat_group)
4900 for (cgraph_node *next
4901 = dyn_cast<cgraph_node *> (node->same_comdat_group);
4902 next != node;
4903 next = dyn_cast<cgraph_node *> (next->same_comdat_group))
4904 next->call_for_symbol_thunks_and_aliases (clear_decl_external,
4905 NULL, true);
4906 }
4907
4908 /* If we're going to need to write this function out, and
4909 there's already a body for it, create RTL for it now.
4910 (There might be no body if this is a method we haven't
4911 gotten around to synthesizing yet.) */
4912 if (!DECL_EXTERNAL (decl)
4913 && decl_needed_p (decl)
4914 && !TREE_ASM_WRITTEN (decl)
4915 && !node->definition)
4916 {
4917 /* We will output the function; no longer consider it in this
4918 loop. */
4919 DECL_DEFER_OUTPUT (decl) = 0;
4920 /* Generate RTL for this function now that we know we
4921 need it. */
4922 expand_or_defer_fn (decl);
4923 reconsider = true;
4924 }
4925 }
4926
4927 if (wrapup_namespace_globals ())
4928 reconsider = true;
4929
4930 /* Static data members are just like namespace-scope globals. */
4931 FOR_EACH_VEC_SAFE_ELT (pending_statics, i, decl)
4932 {
4933 if (var_finalized_p (decl) || DECL_REALLY_EXTERN (decl)
4934 /* Don't write it out if we haven't seen a definition. */
4935 || (DECL_IN_AGGR_P (decl) && !DECL_INLINE_VAR_P (decl))
4936 /* Or haven't instantiated it. */
4937 || (DECL_TEMPLATE_INSTANTIATION (decl)
4938 && !DECL_TEMPLATE_INSTANTIATED (decl)))
4939 continue;
4940 import_export_decl (decl);
4941 /* If this static data member is needed, provide it to the
4942 back end. */
4943 if (DECL_NOT_REALLY_EXTERN (decl) && decl_needed_p (decl))
4944 DECL_EXTERNAL (decl) = 0;
4945 }
4946 if (vec_safe_length (pending_statics) != 0
4947 && wrapup_global_declarations (pending_statics->address (),
4948 pending_statics->length ()))
4949 reconsider = true;
4950
4951 retries++;
4952 }
4953 while (reconsider);
4954
4955 lower_var_init ();
4956
4957 generate_mangling_aliases ();
4958
4959 /* All used inline functions must have a definition at this point. */
4960 FOR_EACH_VEC_SAFE_ELT (deferred_fns, i, decl)
4961 {
4962 if (/* Check online inline functions that were actually used. */
4963 DECL_ODR_USED (decl) && DECL_DECLARED_INLINE_P (decl)
4964 /* If the definition actually was available here, then the
4965 fact that the function was not defined merely represents
4966 that for some reason (use of a template repository,
4967 #pragma interface, etc.) we decided not to emit the
4968 definition here. */
4969 && !DECL_INITIAL (decl)
4970 /* Don't complain if the template was defined. */
4971 && !(DECL_TEMPLATE_INSTANTIATION (decl)
4972 && DECL_INITIAL (DECL_TEMPLATE_RESULT
4973 (template_for_substitution (decl)))))
4974 {
4975 warning_at (DECL_SOURCE_LOCATION (decl), 0,
4976 "inline function %qD used but never defined", decl);
4977 /* Avoid a duplicate warning from check_global_declaration. */
4978 TREE_NO_WARNING (decl) = 1;
4979 }
4980 }
4981
4982 /* So must decls that use a type with no linkage. */
4983 FOR_EACH_VEC_SAFE_ELT (no_linkage_decls, i, decl)
4984 no_linkage_error (decl);
4985
4986 maybe_warn_sized_delete ();
4987
4988 /* Then, do the Objective-C stuff. This is where all the
4989 Objective-C module stuff gets generated (symtab,
4990 class/protocol/selector lists etc). This must be done after C++
4991 templates, destructors etc. so that selectors used in C++
4992 templates are properly allocated. */
4993 if (c_dialect_objc ())
4994 objc_write_global_declarations ();
4995
4996 /* We give C linkage to static constructors and destructors. */
4997 push_lang_context (lang_name_c);
4998
4999 /* Generate initialization and destruction functions for all
5000 priorities for which they are required. */
5001 if (priority_info_map)
5002 splay_tree_foreach (priority_info_map,
5003 generate_ctor_and_dtor_functions_for_priority,
5004 /*data=*/&locus_at_end_of_parsing);
5005 else if (c_dialect_objc () && objc_static_init_needed_p ())
5006 /* If this is obj-c++ and we need a static init, call
5007 generate_ctor_or_dtor_function. */
5008 generate_ctor_or_dtor_function (/*constructor_p=*/true,
5009 DEFAULT_INIT_PRIORITY,
5010 &locus_at_end_of_parsing);
5011
5012 /* We're done with the splay-tree now. */
5013 if (priority_info_map)
5014 splay_tree_delete (priority_info_map);
5015
5016 /* Generate any missing aliases. */
5017 maybe_apply_pending_pragma_weaks ();
5018
5019 /* We're done with static constructors, so we can go back to "C++"
5020 linkage now. */
5021 pop_lang_context ();
5022
5023 if (flag_vtable_verify)
5024 {
5025 vtv_recover_class_info ();
5026 vtv_compute_class_hierarchy_transitive_closure ();
5027 vtv_build_vtable_verify_fndecl ();
5028 }
5029
5030 perform_deferred_noexcept_checks ();
5031
5032 finish_repo ();
5033 fini_constexpr ();
5034
5035 /* The entire file is now complete. If requested, dump everything
5036 to a file. */
5037 dump_tu ();
5038
5039 if (flag_detailed_statistics)
5040 {
5041 dump_tree_statistics ();
5042 dump_time_statistics ();
5043 }
5044
5045 timevar_stop (TV_PHASE_DEFERRED);
5046 timevar_start (TV_PHASE_PARSING);
5047
5048 /* Indicate that we're done with front end processing. */
5049 at_eof = 2;
5050 }
5051
5052 /* Perform any post compilation-proper cleanups for the C++ front-end.
5053 This should really go away. No front-end should need to do
5054 anything past the compilation process. */
5055
5056 void
cxx_post_compilation_parsing_cleanups(void)5057 cxx_post_compilation_parsing_cleanups (void)
5058 {
5059 timevar_start (TV_PHASE_LATE_PARSING_CLEANUPS);
5060
5061 if (flag_vtable_verify)
5062 {
5063 /* Generate the special constructor initialization function that
5064 calls __VLTRegisterPairs, and give it a very high
5065 initialization priority. This must be done after
5066 finalize_compilation_unit so that we have accurate
5067 information about which vtable will actually be emitted. */
5068 vtv_generate_init_routine ();
5069 }
5070
5071 input_location = locus_at_end_of_parsing;
5072
5073 if (flag_checking)
5074 validate_conversion_obstack ();
5075
5076 timevar_stop (TV_PHASE_LATE_PARSING_CLEANUPS);
5077 }
5078
5079 /* FN is an OFFSET_REF, DOTSTAR_EXPR or MEMBER_REF indicating the
5080 function to call in parse-tree form; it has not yet been
5081 semantically analyzed. ARGS are the arguments to the function.
5082 They have already been semantically analyzed. This may change
5083 ARGS. */
5084
5085 tree
build_offset_ref_call_from_tree(tree fn,vec<tree,va_gc> ** args,tsubst_flags_t complain)5086 build_offset_ref_call_from_tree (tree fn, vec<tree, va_gc> **args,
5087 tsubst_flags_t complain)
5088 {
5089 tree orig_fn;
5090 vec<tree, va_gc> *orig_args = NULL;
5091 tree expr;
5092 tree object;
5093
5094 orig_fn = fn;
5095 object = TREE_OPERAND (fn, 0);
5096
5097 if (processing_template_decl)
5098 {
5099 gcc_assert (TREE_CODE (fn) == DOTSTAR_EXPR
5100 || TREE_CODE (fn) == MEMBER_REF);
5101 if (type_dependent_expression_p (fn)
5102 || any_type_dependent_arguments_p (*args))
5103 return build_min_nt_call_vec (fn, *args);
5104
5105 orig_args = make_tree_vector_copy (*args);
5106
5107 /* Transform the arguments and add the implicit "this"
5108 parameter. That must be done before the FN is transformed
5109 because we depend on the form of FN. */
5110 make_args_non_dependent (*args);
5111 object = build_non_dependent_expr (object);
5112 if (TREE_CODE (TREE_TYPE (fn)) == METHOD_TYPE)
5113 {
5114 if (TREE_CODE (fn) == DOTSTAR_EXPR)
5115 object = cp_build_addr_expr (object, complain);
5116 vec_safe_insert (*args, 0, object);
5117 }
5118 /* Now that the arguments are done, transform FN. */
5119 fn = build_non_dependent_expr (fn);
5120 }
5121
5122 /* A qualified name corresponding to a bound pointer-to-member is
5123 represented as an OFFSET_REF:
5124
5125 struct B { void g(); };
5126 void (B::*p)();
5127 void B::g() { (this->*p)(); } */
5128 if (TREE_CODE (fn) == OFFSET_REF)
5129 {
5130 tree object_addr = cp_build_addr_expr (object, complain);
5131 fn = TREE_OPERAND (fn, 1);
5132 fn = get_member_function_from_ptrfunc (&object_addr, fn,
5133 complain);
5134 vec_safe_insert (*args, 0, object_addr);
5135 }
5136
5137 if (CLASS_TYPE_P (TREE_TYPE (fn)))
5138 expr = build_op_call (fn, args, complain);
5139 else
5140 expr = cp_build_function_call_vec (fn, args, complain);
5141 if (processing_template_decl && expr != error_mark_node)
5142 expr = build_min_non_dep_call_vec (expr, orig_fn, orig_args);
5143
5144 if (orig_args != NULL)
5145 release_tree_vector (orig_args);
5146
5147 return expr;
5148 }
5149
5150
5151 void
check_default_args(tree x)5152 check_default_args (tree x)
5153 {
5154 tree arg = TYPE_ARG_TYPES (TREE_TYPE (x));
5155 bool saw_def = false;
5156 int i = 0 - (TREE_CODE (TREE_TYPE (x)) == METHOD_TYPE);
5157 for (; arg && arg != void_list_node; arg = TREE_CHAIN (arg), ++i)
5158 {
5159 if (TREE_PURPOSE (arg))
5160 saw_def = true;
5161 else if (saw_def && !PACK_EXPANSION_P (TREE_VALUE (arg)))
5162 {
5163 error ("default argument missing for parameter %P of %q+#D", i, x);
5164 TREE_PURPOSE (arg) = error_mark_node;
5165 }
5166 }
5167 }
5168
5169 /* Return true if function DECL can be inlined. This is used to force
5170 instantiation of methods that might be interesting for inlining. */
5171 bool
possibly_inlined_p(tree decl)5172 possibly_inlined_p (tree decl)
5173 {
5174 gcc_assert (TREE_CODE (decl) == FUNCTION_DECL);
5175 if (DECL_UNINLINABLE (decl))
5176 return false;
5177 if (!optimize)
5178 return DECL_DECLARED_INLINE_P (decl);
5179 /* When optimizing, we might inline everything when flatten
5180 attribute or heuristics inlining for size or autoinlining
5181 is used. */
5182 return true;
5183 }
5184
5185 /* Normally, we can wait until instantiation-time to synthesize DECL.
5186 However, if DECL is a static data member initialized with a constant
5187 or a constexpr function, we need it right now because a reference to
5188 such a data member or a call to such function is not value-dependent.
5189 For a function that uses auto in the return type, we need to instantiate
5190 it to find out its type. For OpenMP user defined reductions, we need
5191 them instantiated for reduction clauses which inline them by hand
5192 directly. */
5193
5194 static void
maybe_instantiate_decl(tree decl)5195 maybe_instantiate_decl (tree decl)
5196 {
5197 if (DECL_LANG_SPECIFIC (decl)
5198 && DECL_TEMPLATE_INFO (decl)
5199 && (decl_maybe_constant_var_p (decl)
5200 || (TREE_CODE (decl) == FUNCTION_DECL
5201 && DECL_OMP_DECLARE_REDUCTION_P (decl))
5202 || undeduced_auto_decl (decl))
5203 && !DECL_DECLARED_CONCEPT_P (decl)
5204 && !uses_template_parms (DECL_TI_ARGS (decl)))
5205 {
5206 /* Instantiating a function will result in garbage collection. We
5207 must treat this situation as if we were within the body of a
5208 function so as to avoid collecting live data only referenced from
5209 the stack (such as overload resolution candidates). */
5210 ++function_depth;
5211 instantiate_decl (decl, /*defer_ok=*/false,
5212 /*expl_inst_class_mem_p=*/false);
5213 --function_depth;
5214 }
5215 }
5216
5217 /* Mark DECL (either a _DECL or a BASELINK) as "used" in the program.
5218 If DECL is a specialization or implicitly declared class member,
5219 generate the actual definition. Return false if something goes
5220 wrong, true otherwise. */
5221
5222 bool
mark_used(tree decl,tsubst_flags_t complain)5223 mark_used (tree decl, tsubst_flags_t complain)
5224 {
5225 /* If we're just testing conversions or resolving overloads, we
5226 don't want any permanent effects like forcing functions to be
5227 output or instantiating templates. */
5228 if ((complain & tf_conv))
5229 return true;
5230
5231 /* If DECL is a BASELINK for a single function, then treat it just
5232 like the DECL for the function. Otherwise, if the BASELINK is
5233 for an overloaded function, we don't know which function was
5234 actually used until after overload resolution. */
5235 if (BASELINK_P (decl))
5236 {
5237 decl = BASELINK_FUNCTIONS (decl);
5238 if (really_overloaded_fn (decl))
5239 return true;
5240 decl = OVL_FIRST (decl);
5241 }
5242
5243 /* Set TREE_USED for the benefit of -Wunused. */
5244 TREE_USED (decl) = 1;
5245 /* And for structured bindings also the underlying decl. */
5246 if (DECL_DECOMPOSITION_P (decl) && DECL_DECOMP_BASE (decl))
5247 TREE_USED (DECL_DECOMP_BASE (decl)) = 1;
5248
5249 if (TREE_CODE (decl) == TEMPLATE_DECL)
5250 return true;
5251
5252 if (DECL_CLONED_FUNCTION_P (decl))
5253 TREE_USED (DECL_CLONED_FUNCTION (decl)) = 1;
5254
5255 /* Mark enumeration types as used. */
5256 if (TREE_CODE (decl) == CONST_DECL)
5257 used_types_insert (DECL_CONTEXT (decl));
5258
5259 if (TREE_CODE (decl) == FUNCTION_DECL
5260 && !maybe_instantiate_noexcept (decl, complain))
5261 return false;
5262
5263 if (TREE_CODE (decl) == FUNCTION_DECL
5264 && DECL_DELETED_FN (decl))
5265 {
5266 if (DECL_ARTIFICIAL (decl)
5267 && DECL_CONV_FN_P (decl)
5268 && LAMBDA_TYPE_P (DECL_CONTEXT (decl)))
5269 /* We mark a lambda conversion op as deleted if we can't
5270 generate it properly; see maybe_add_lambda_conv_op. */
5271 sorry ("converting lambda that uses %<...%> to function pointer");
5272 else if (complain & tf_error)
5273 {
5274 error ("use of deleted function %qD", decl);
5275 if (!maybe_explain_implicit_delete (decl))
5276 inform (DECL_SOURCE_LOCATION (decl), "declared here");
5277 }
5278 return false;
5279 }
5280
5281 if (TREE_DEPRECATED (decl) && (complain & tf_warning)
5282 && deprecated_state != DEPRECATED_SUPPRESS)
5283 warn_deprecated_use (decl, NULL_TREE);
5284
5285 /* We can only check DECL_ODR_USED on variables or functions with
5286 DECL_LANG_SPECIFIC set, and these are also the only decls that we
5287 might need special handling for. */
5288 if (!VAR_OR_FUNCTION_DECL_P (decl)
5289 || DECL_LANG_SPECIFIC (decl) == NULL
5290 || DECL_THUNK_P (decl))
5291 {
5292 if (!processing_template_decl
5293 && !require_deduced_type (decl, complain))
5294 return false;
5295 return true;
5296 }
5297
5298 /* We only want to do this processing once. We don't need to keep trying
5299 to instantiate inline templates, because unit-at-a-time will make sure
5300 we get them compiled before functions that want to inline them. */
5301 if (DECL_ODR_USED (decl))
5302 return true;
5303
5304 /* Normally, we can wait until instantiation-time to synthesize DECL.
5305 However, if DECL is a static data member initialized with a constant
5306 or a constexpr function, we need it right now because a reference to
5307 such a data member or a call to such function is not value-dependent.
5308 For a function that uses auto in the return type, we need to instantiate
5309 it to find out its type. For OpenMP user defined reductions, we need
5310 them instantiated for reduction clauses which inline them by hand
5311 directly. */
5312 maybe_instantiate_decl (decl);
5313
5314 if (processing_template_decl || in_template_function ())
5315 return true;
5316
5317 /* Check this too in case we're within instantiate_non_dependent_expr. */
5318 if (DECL_TEMPLATE_INFO (decl)
5319 && uses_template_parms (DECL_TI_ARGS (decl)))
5320 return true;
5321
5322 if (!require_deduced_type (decl, complain))
5323 return false;
5324
5325 if (builtin_pack_fn_p (decl))
5326 {
5327 error ("use of built-in parameter pack %qD outside of a template",
5328 DECL_NAME (decl));
5329 return false;
5330 }
5331
5332 /* If we don't need a value, then we don't need to synthesize DECL. */
5333 if (cp_unevaluated_operand || in_discarded_stmt)
5334 return true;
5335
5336 DECL_ODR_USED (decl) = 1;
5337 if (DECL_CLONED_FUNCTION_P (decl))
5338 DECL_ODR_USED (DECL_CLONED_FUNCTION (decl)) = 1;
5339
5340 /* DR 757: A type without linkage shall not be used as the type of a
5341 variable or function with linkage, unless
5342 o the variable or function has extern "C" linkage (7.5 [dcl.link]), or
5343 o the variable or function is not used (3.2 [basic.def.odr]) or is
5344 defined in the same translation unit. */
5345 if (cxx_dialect > cxx98
5346 && decl_linkage (decl) != lk_none
5347 && !DECL_EXTERN_C_P (decl)
5348 && !DECL_ARTIFICIAL (decl)
5349 && !decl_defined_p (decl)
5350 && no_linkage_check (TREE_TYPE (decl), /*relaxed_p=*/false))
5351 {
5352 if (is_local_extern (decl))
5353 /* There's no way to define a local extern, and adding it to
5354 the vector interferes with GC, so give an error now. */
5355 no_linkage_error (decl);
5356 else
5357 vec_safe_push (no_linkage_decls, decl);
5358 }
5359
5360 if (TREE_CODE (decl) == FUNCTION_DECL && DECL_DECLARED_INLINE_P (decl)
5361 && !DECL_INITIAL (decl) && !DECL_ARTIFICIAL (decl))
5362 /* Remember it, so we can check it was defined. */
5363 note_vague_linkage_fn (decl);
5364
5365 /* Is it a synthesized method that needs to be synthesized? */
5366 if (TREE_CODE (decl) == FUNCTION_DECL
5367 && DECL_NONSTATIC_MEMBER_FUNCTION_P (decl)
5368 && DECL_DEFAULTED_FN (decl)
5369 /* A function defaulted outside the class is synthesized either by
5370 cp_finish_decl or instantiate_decl. */
5371 && !DECL_DEFAULTED_OUTSIDE_CLASS_P (decl)
5372 && ! DECL_INITIAL (decl))
5373 {
5374 /* Defer virtual destructors so that thunks get the right
5375 linkage. */
5376 if (DECL_VIRTUAL_P (decl) && !at_eof)
5377 {
5378 note_vague_linkage_fn (decl);
5379 return true;
5380 }
5381
5382 /* Remember the current location for a function we will end up
5383 synthesizing. Then we can inform the user where it was
5384 required in the case of error. */
5385 DECL_SOURCE_LOCATION (decl) = input_location;
5386
5387 /* Synthesizing an implicitly defined member function will result in
5388 garbage collection. We must treat this situation as if we were
5389 within the body of a function so as to avoid collecting live data
5390 on the stack (such as overload resolution candidates).
5391
5392 We could just let cp_write_global_declarations handle synthesizing
5393 this function by adding it to deferred_fns, but doing
5394 it at the use site produces better error messages. */
5395 ++function_depth;
5396 synthesize_method (decl);
5397 --function_depth;
5398 /* If this is a synthesized method we don't need to
5399 do the instantiation test below. */
5400 }
5401 else if (VAR_OR_FUNCTION_DECL_P (decl)
5402 && DECL_TEMPLATE_INFO (decl)
5403 && !DECL_DECLARED_CONCEPT_P (decl)
5404 && (!DECL_EXPLICIT_INSTANTIATION (decl)
5405 || always_instantiate_p (decl)))
5406 /* If this is a function or variable that is an instance of some
5407 template, we now know that we will need to actually do the
5408 instantiation. We check that DECL is not an explicit
5409 instantiation because that is not checked in instantiate_decl.
5410
5411 We put off instantiating functions in order to improve compile
5412 times. Maintaining a stack of active functions is expensive,
5413 and the inliner knows to instantiate any functions it might
5414 need. Therefore, we always try to defer instantiation. */
5415 {
5416 ++function_depth;
5417 instantiate_decl (decl, /*defer_ok=*/true,
5418 /*expl_inst_class_mem_p=*/false);
5419 --function_depth;
5420 }
5421
5422 return true;
5423 }
5424
5425 bool
mark_used(tree decl)5426 mark_used (tree decl)
5427 {
5428 return mark_used (decl, tf_warning_or_error);
5429 }
5430
5431 tree
vtv_start_verification_constructor_init_function(void)5432 vtv_start_verification_constructor_init_function (void)
5433 {
5434 return start_objects ('I', MAX_RESERVED_INIT_PRIORITY - 1);
5435 }
5436
5437 tree
vtv_finish_verification_constructor_init_function(tree function_body)5438 vtv_finish_verification_constructor_init_function (tree function_body)
5439 {
5440 tree fn;
5441
5442 finish_compound_stmt (function_body);
5443 fn = finish_function (/*inline_p=*/false);
5444 DECL_STATIC_CONSTRUCTOR (fn) = 1;
5445 decl_init_priority_insert (fn, MAX_RESERVED_INIT_PRIORITY - 1);
5446
5447 return fn;
5448 }
5449
5450 #include "gt-cp-decl2.h"
5451