1 /* Process declarations and variables for C++ compiler.
2    Copyright (C) 1988-2014 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 "tm.h"
33 #include "tree.h"
34 #include "stringpool.h"
35 #include "varasm.h"
36 #include "attribs.h"
37 #include "stor-layout.h"
38 #include "calls.h"
39 #include "pointer-set.h"
40 #include "flags.h"
41 #include "cp-tree.h"
42 #include "decl.h"
43 #include "toplev.h"
44 #include "timevar.h"
45 #include "cpplib.h"
46 #include "target.h"
47 #include "c-family/c-common.h"
48 #include "c-family/c-objc.h"
49 #include "cgraph.h"
50 #include "tree-inline.h"
51 #include "c-family/c-pragma.h"
52 #include "dumpfile.h"
53 #include "intl.h"
54 #include "splay-tree.h"
55 #include "langhooks.h"
56 #include "c-family/c-ada-spec.h"
57 #include "asan.h"
58 
59 extern cpp_reader *parse_in;
60 
61 /* This structure contains information about the initializations
62    and/or destructions required for a particular priority level.  */
63 typedef struct priority_info_s {
64   /* Nonzero if there have been any initializations at this priority
65      throughout the translation unit.  */
66   int initializations_p;
67   /* Nonzero if there have been any destructions at this priority
68      throughout the translation unit.  */
69   int destructions_p;
70 } *priority_info;
71 
72 static void mark_vtable_entries (tree);
73 static bool maybe_emit_vtables (tree);
74 static bool acceptable_java_type (tree);
75 static tree start_objects (int, int);
76 static void finish_objects (int, int, tree);
77 static tree start_static_storage_duration_function (unsigned);
78 static void finish_static_storage_duration_function (tree);
79 static priority_info get_priority_info (int);
80 static void do_static_initialization_or_destruction (tree, bool);
81 static void one_static_initialization_or_destruction (tree, tree, bool);
82 static void generate_ctor_or_dtor_function (bool, int, location_t *);
83 static int generate_ctor_and_dtor_functions_for_priority (splay_tree_node,
84 							  void *);
85 static tree prune_vars_needing_no_initialization (tree *);
86 static void write_out_vars (tree);
87 static void import_export_class (tree);
88 static tree get_guard_bits (tree);
89 static void determine_visibility_from_class (tree, tree);
90 static bool determine_hidden_inline (tree);
91 static bool decl_defined_p (tree);
92 
93 /* A list of static class variables.  This is needed, because a
94    static class variable can be declared inside the class without
95    an initializer, and then initialized, statically, outside the class.  */
96 static GTY(()) vec<tree, va_gc> *pending_statics;
97 
98 /* A list of functions which were declared inline, but which we
99    may need to emit outline anyway.  */
100 static GTY(()) vec<tree, va_gc> *deferred_fns;
101 
102 /* A list of functions which we might want to set DECL_COMDAT on at EOF.  */
103 
104 static GTY(()) vec<tree, va_gc> *maybe_comdat_fns;
105 
106 /* A list of decls that use types with no linkage, which we need to make
107    sure are defined.  */
108 static GTY(()) vec<tree, va_gc> *no_linkage_decls;
109 
110 /* Nonzero if we're done parsing and into end-of-file activities.  */
111 
112 int at_eof;
113 
114 
115 /* Return a member function type (a METHOD_TYPE), given FNTYPE (a
116    FUNCTION_TYPE), CTYPE (class type), and QUALS (the cv-qualifiers
117    that apply to the function).  */
118 
119 tree
build_memfn_type(tree fntype,tree ctype,cp_cv_quals quals,cp_ref_qualifier rqual)120 build_memfn_type (tree fntype, tree ctype, cp_cv_quals quals,
121 		  cp_ref_qualifier rqual)
122 {
123   tree raises;
124   tree attrs;
125   int type_quals;
126 
127   if (fntype == error_mark_node || ctype == error_mark_node)
128     return error_mark_node;
129 
130   gcc_assert (TREE_CODE (fntype) == FUNCTION_TYPE
131 	      || TREE_CODE (fntype) == METHOD_TYPE);
132 
133   type_quals = quals & ~TYPE_QUAL_RESTRICT;
134   ctype = cp_build_qualified_type (ctype, type_quals);
135   raises = TYPE_RAISES_EXCEPTIONS (fntype);
136   attrs = TYPE_ATTRIBUTES (fntype);
137   fntype = build_method_type_directly (ctype, TREE_TYPE (fntype),
138 				       (TREE_CODE (fntype) == METHOD_TYPE
139 					? TREE_CHAIN (TYPE_ARG_TYPES (fntype))
140 					: TYPE_ARG_TYPES (fntype)));
141   if (attrs)
142     fntype = cp_build_type_attribute_variant (fntype, attrs);
143   if (rqual)
144     fntype = build_ref_qualified_type (fntype, rqual);
145   if (raises)
146     fntype = build_exception_variant (fntype, raises);
147 
148   return fntype;
149 }
150 
151 /* Return a variant of FNTYPE, a FUNCTION_TYPE or METHOD_TYPE, with its
152    return type changed to NEW_RET.  */
153 
154 tree
change_return_type(tree new_ret,tree fntype)155 change_return_type (tree new_ret, tree fntype)
156 {
157   tree newtype;
158   tree args = TYPE_ARG_TYPES (fntype);
159   tree raises = TYPE_RAISES_EXCEPTIONS (fntype);
160   tree attrs = TYPE_ATTRIBUTES (fntype);
161 
162   if (new_ret == error_mark_node)
163     return fntype;
164 
165   if (same_type_p (new_ret, TREE_TYPE (fntype)))
166     return fntype;
167 
168   if (TREE_CODE (fntype) == FUNCTION_TYPE)
169     {
170       newtype = build_function_type (new_ret, args);
171       newtype = apply_memfn_quals (newtype,
172 				   type_memfn_quals (fntype),
173 				   type_memfn_rqual (fntype));
174     }
175   else
176     newtype = build_method_type_directly
177       (class_of_this_parm (fntype), new_ret, TREE_CHAIN (args));
178   if (raises)
179     newtype = build_exception_variant (newtype, raises);
180   if (attrs)
181     newtype = cp_build_type_attribute_variant (newtype, attrs);
182 
183   return newtype;
184 }
185 
186 /* Build a PARM_DECL with NAME and TYPE, and set DECL_ARG_TYPE
187    appropriately.  */
188 
189 tree
cp_build_parm_decl(tree name,tree type)190 cp_build_parm_decl (tree name, tree type)
191 {
192   tree parm = build_decl (input_location,
193 			  PARM_DECL, name, type);
194   /* DECL_ARG_TYPE is only used by the back end and the back end never
195      sees templates.  */
196   if (!processing_template_decl)
197     DECL_ARG_TYPE (parm) = type_passed_as (type);
198 
199   return parm;
200 }
201 
202 /* Returns a PARM_DECL for a parameter of the indicated TYPE, with the
203    indicated NAME.  */
204 
205 tree
build_artificial_parm(tree name,tree type)206 build_artificial_parm (tree name, tree type)
207 {
208   tree parm = cp_build_parm_decl (name, type);
209   DECL_ARTIFICIAL (parm) = 1;
210   /* All our artificial parms are implicitly `const'; they cannot be
211      assigned to.  */
212   TREE_READONLY (parm) = 1;
213   return parm;
214 }
215 
216 /* Constructors for types with virtual baseclasses need an "in-charge" flag
217    saying whether this constructor is responsible for initialization of
218    virtual baseclasses or not.  All destructors also need this "in-charge"
219    flag, which additionally determines whether or not the destructor should
220    free the memory for the object.
221 
222    This function adds the "in-charge" flag to member function FN if
223    appropriate.  It is called from grokclassfn and tsubst.
224    FN must be either a constructor or destructor.
225 
226    The in-charge flag follows the 'this' parameter, and is followed by the
227    VTT parm (if any), then the user-written parms.  */
228 
229 void
maybe_retrofit_in_chrg(tree fn)230 maybe_retrofit_in_chrg (tree fn)
231 {
232   tree basetype, arg_types, parms, parm, fntype;
233 
234   /* If we've already add the in-charge parameter don't do it again.  */
235   if (DECL_HAS_IN_CHARGE_PARM_P (fn))
236     return;
237 
238   /* When processing templates we can't know, in general, whether or
239      not we're going to have virtual baseclasses.  */
240   if (processing_template_decl)
241     return;
242 
243   /* We don't need an in-charge parameter for constructors that don't
244      have virtual bases.  */
245   if (DECL_CONSTRUCTOR_P (fn)
246       && !CLASSTYPE_VBASECLASSES (DECL_CONTEXT (fn)))
247     return;
248 
249   arg_types = TYPE_ARG_TYPES (TREE_TYPE (fn));
250   basetype = TREE_TYPE (TREE_VALUE (arg_types));
251   arg_types = TREE_CHAIN (arg_types);
252 
253   parms = DECL_CHAIN (DECL_ARGUMENTS (fn));
254 
255   /* If this is a subobject constructor or destructor, our caller will
256      pass us a pointer to our VTT.  */
257   if (CLASSTYPE_VBASECLASSES (DECL_CONTEXT (fn)))
258     {
259       parm = build_artificial_parm (vtt_parm_identifier, vtt_parm_type);
260 
261       /* First add it to DECL_ARGUMENTS between 'this' and the real args...  */
262       DECL_CHAIN (parm) = parms;
263       parms = parm;
264 
265       /* ...and then to TYPE_ARG_TYPES.  */
266       arg_types = hash_tree_chain (vtt_parm_type, arg_types);
267 
268       DECL_HAS_VTT_PARM_P (fn) = 1;
269     }
270 
271   /* Then add the in-charge parm (before the VTT parm).  */
272   parm = build_artificial_parm (in_charge_identifier, integer_type_node);
273   DECL_CHAIN (parm) = parms;
274   parms = parm;
275   arg_types = hash_tree_chain (integer_type_node, arg_types);
276 
277   /* Insert our new parameter(s) into the list.  */
278   DECL_CHAIN (DECL_ARGUMENTS (fn)) = parms;
279 
280   /* And rebuild the function type.  */
281   fntype = build_method_type_directly (basetype, TREE_TYPE (TREE_TYPE (fn)),
282 				       arg_types);
283   if (TYPE_RAISES_EXCEPTIONS (TREE_TYPE (fn)))
284     fntype = build_exception_variant (fntype,
285 				      TYPE_RAISES_EXCEPTIONS (TREE_TYPE (fn)));
286   if (TYPE_ATTRIBUTES (TREE_TYPE (fn)))
287     fntype = (cp_build_type_attribute_variant
288 	      (fntype, TYPE_ATTRIBUTES (TREE_TYPE (fn))));
289   TREE_TYPE (fn) = fntype;
290 
291   /* Now we've got the in-charge parameter.  */
292   DECL_HAS_IN_CHARGE_PARM_P (fn) = 1;
293 }
294 
295 /* Classes overload their constituent function names automatically.
296    When a function name is declared in a record structure,
297    its name is changed to it overloaded name.  Since names for
298    constructors and destructors can conflict, we place a leading
299    '$' for destructors.
300 
301    CNAME is the name of the class we are grokking for.
302 
303    FUNCTION is a FUNCTION_DECL.  It was created by `grokdeclarator'.
304 
305    FLAGS contains bits saying what's special about today's
306    arguments.  DTOR_FLAG == DESTRUCTOR.
307 
308    If FUNCTION is a destructor, then we must add the `auto-delete' field
309    as a second parameter.  There is some hair associated with the fact
310    that we must "declare" this variable in the manner consistent with the
311    way the rest of the arguments were declared.
312 
313    QUALS are the qualifiers for the this pointer.  */
314 
315 void
grokclassfn(tree ctype,tree function,enum overload_flags flags)316 grokclassfn (tree ctype, tree function, enum overload_flags flags)
317 {
318   tree fn_name = DECL_NAME (function);
319 
320   /* Even within an `extern "C"' block, members get C++ linkage.  See
321      [dcl.link] for details.  */
322   SET_DECL_LANGUAGE (function, lang_cplusplus);
323 
324   if (fn_name == NULL_TREE)
325     {
326       error ("name missing for member function");
327       fn_name = get_identifier ("<anonymous>");
328       DECL_NAME (function) = fn_name;
329     }
330 
331   DECL_CONTEXT (function) = ctype;
332 
333   if (flags == DTOR_FLAG)
334     DECL_DESTRUCTOR_P (function) = 1;
335 
336   if (flags == DTOR_FLAG || DECL_CONSTRUCTOR_P (function))
337     maybe_retrofit_in_chrg (function);
338 }
339 
340 /* Create an ARRAY_REF, checking for the user doing things backwards
341    along the way.  DECLTYPE_P is for N3276, as in the parser.  */
342 
343 tree
grok_array_decl(location_t loc,tree array_expr,tree index_exp,bool decltype_p)344 grok_array_decl (location_t loc, tree array_expr, tree index_exp,
345 		 bool decltype_p)
346 {
347   tree type;
348   tree expr;
349   tree orig_array_expr = array_expr;
350   tree orig_index_exp = index_exp;
351 
352   if (error_operand_p (array_expr) || error_operand_p (index_exp))
353     return error_mark_node;
354 
355   if (processing_template_decl)
356     {
357       if (type_dependent_expression_p (array_expr)
358 	  || type_dependent_expression_p (index_exp))
359 	return build_min_nt_loc (loc, ARRAY_REF, array_expr, index_exp,
360 				 NULL_TREE, NULL_TREE);
361       array_expr = build_non_dependent_expr (array_expr);
362       index_exp = build_non_dependent_expr (index_exp);
363     }
364 
365   type = TREE_TYPE (array_expr);
366   gcc_assert (type);
367   type = non_reference (type);
368 
369   /* If they have an `operator[]', use that.  */
370   if (MAYBE_CLASS_TYPE_P (type) || MAYBE_CLASS_TYPE_P (TREE_TYPE (index_exp)))
371     {
372       tsubst_flags_t complain = tf_warning_or_error;
373       if (decltype_p)
374 	complain |= tf_decltype;
375       expr = build_new_op (loc, ARRAY_REF, LOOKUP_NORMAL, array_expr,
376 			   index_exp, NULL_TREE, /*overload=*/NULL, complain);
377     }
378   else
379     {
380       tree p1, p2, i1, i2;
381 
382       /* Otherwise, create an ARRAY_REF for a pointer or array type.
383 	 It is a little-known fact that, if `a' is an array and `i' is
384 	 an int, you can write `i[a]', which means the same thing as
385 	 `a[i]'.  */
386       if (TREE_CODE (type) == ARRAY_TYPE || TREE_CODE (type) == VECTOR_TYPE)
387 	p1 = array_expr;
388       else
389 	p1 = build_expr_type_conversion (WANT_POINTER, array_expr, false);
390 
391       if (TREE_CODE (TREE_TYPE (index_exp)) == ARRAY_TYPE)
392 	p2 = index_exp;
393       else
394 	p2 = build_expr_type_conversion (WANT_POINTER, index_exp, false);
395 
396       i1 = build_expr_type_conversion (WANT_INT | WANT_ENUM, array_expr,
397 				       false);
398       i2 = build_expr_type_conversion (WANT_INT | WANT_ENUM, index_exp,
399 				       false);
400 
401       if ((p1 && i2) && (i1 && p2))
402 	error ("ambiguous conversion for array subscript");
403 
404       if (p1 && i2)
405 	array_expr = p1, index_exp = i2;
406       else if (i1 && p2)
407 	array_expr = p2, index_exp = i1;
408       else
409 	{
410 	  error ("invalid types %<%T[%T]%> for array subscript",
411 		 type, TREE_TYPE (index_exp));
412 	  return error_mark_node;
413 	}
414 
415       if (array_expr == error_mark_node || index_exp == error_mark_node)
416 	error ("ambiguous conversion for array subscript");
417 
418       expr = build_array_ref (input_location, array_expr, index_exp);
419     }
420   if (processing_template_decl && expr != error_mark_node)
421     return build_min_non_dep (ARRAY_REF, expr, orig_array_expr, orig_index_exp,
422 			      NULL_TREE, NULL_TREE);
423   return expr;
424 }
425 
426 /* Given the cast expression EXP, checking out its validity.   Either return
427    an error_mark_node if there was an unavoidable error, return a cast to
428    void for trying to delete a pointer w/ the value 0, or return the
429    call to delete.  If DOING_VEC is true, we handle things differently
430    for doing an array delete.
431    Implements ARM $5.3.4.  This is called from the parser.  */
432 
433 tree
delete_sanity(tree exp,tree size,bool doing_vec,int use_global_delete,tsubst_flags_t complain)434 delete_sanity (tree exp, tree size, bool doing_vec, int use_global_delete,
435 	       tsubst_flags_t complain)
436 {
437   tree t, type;
438 
439   if (exp == error_mark_node)
440     return exp;
441 
442   if (processing_template_decl)
443     {
444       t = build_min (DELETE_EXPR, void_type_node, exp, size);
445       DELETE_EXPR_USE_GLOBAL (t) = use_global_delete;
446       DELETE_EXPR_USE_VEC (t) = doing_vec;
447       TREE_SIDE_EFFECTS (t) = 1;
448       return t;
449     }
450 
451   /* An array can't have been allocated by new, so complain.  */
452   if (TREE_CODE (TREE_TYPE (exp)) == ARRAY_TYPE)
453     warning (0, "deleting array %q#E", exp);
454 
455   t = build_expr_type_conversion (WANT_POINTER, exp, true);
456 
457   if (t == NULL_TREE || t == error_mark_node)
458     {
459       error ("type %q#T argument given to %<delete%>, expected pointer",
460 	     TREE_TYPE (exp));
461       return error_mark_node;
462     }
463 
464   type = TREE_TYPE (t);
465 
466   /* As of Valley Forge, you can delete a pointer to const.  */
467 
468   /* You can't delete functions.  */
469   if (TREE_CODE (TREE_TYPE (type)) == FUNCTION_TYPE)
470     {
471       error ("cannot delete a function.  Only pointer-to-objects are "
472 	     "valid arguments to %<delete%>");
473       return error_mark_node;
474     }
475 
476   /* Deleting ptr to void is undefined behavior [expr.delete/3].  */
477   if (VOID_TYPE_P (TREE_TYPE (type)))
478     {
479       warning (0, "deleting %qT is undefined", type);
480       doing_vec = 0;
481     }
482 
483   /* Deleting a pointer with the value zero is valid and has no effect.  */
484   if (integer_zerop (t))
485     return build1 (NOP_EXPR, void_type_node, t);
486 
487   if (doing_vec)
488     return build_vec_delete (t, /*maxindex=*/NULL_TREE,
489 			     sfk_deleting_destructor,
490 			     use_global_delete, complain);
491   else
492     return build_delete (type, t, sfk_deleting_destructor,
493 			 LOOKUP_NORMAL, use_global_delete,
494 			 complain);
495 }
496 
497 /* Report an error if the indicated template declaration is not the
498    sort of thing that should be a member template.  */
499 
500 void
check_member_template(tree tmpl)501 check_member_template (tree tmpl)
502 {
503   tree decl;
504 
505   gcc_assert (TREE_CODE (tmpl) == TEMPLATE_DECL);
506   decl = DECL_TEMPLATE_RESULT (tmpl);
507 
508   if (TREE_CODE (decl) == FUNCTION_DECL
509       || DECL_ALIAS_TEMPLATE_P (tmpl)
510       || (TREE_CODE (decl) == TYPE_DECL
511 	  && MAYBE_CLASS_TYPE_P (TREE_TYPE (decl))))
512     {
513       /* The parser rejects template declarations in local classes
514 	 (with the exception of generic lambdas).  */
515       gcc_assert (!current_function_decl || LAMBDA_FUNCTION_P (decl));
516       /* The parser rejects any use of virtual in a function template.  */
517       gcc_assert (!(TREE_CODE (decl) == FUNCTION_DECL
518 		    && DECL_VIRTUAL_P (decl)));
519 
520       /* The debug-information generating code doesn't know what to do
521 	 with member templates.  */
522       DECL_IGNORED_P (tmpl) = 1;
523     }
524   else
525     error ("template declaration of %q#D", decl);
526 }
527 
528 /* Return true iff TYPE is a valid Java parameter or return type.  */
529 
530 static bool
acceptable_java_type(tree type)531 acceptable_java_type (tree type)
532 {
533   if (type == error_mark_node)
534     return false;
535 
536   if (VOID_TYPE_P (type) || TYPE_FOR_JAVA (type))
537     return true;
538   if (TYPE_PTR_P (type) || TREE_CODE (type) == REFERENCE_TYPE)
539     {
540       type = TREE_TYPE (type);
541       if (TREE_CODE (type) == RECORD_TYPE)
542 	{
543 	  tree args;  int i;
544 	  if (! TYPE_FOR_JAVA (type))
545 	    return false;
546 	  if (! CLASSTYPE_TEMPLATE_INFO (type))
547 	    return true;
548 	  args = CLASSTYPE_TI_ARGS (type);
549 	  i = TREE_VEC_LENGTH (args);
550 	  while (--i >= 0)
551 	    {
552 	      type = TREE_VEC_ELT (args, i);
553 	      if (TYPE_PTR_P (type))
554 		type = TREE_TYPE (type);
555 	      if (! TYPE_FOR_JAVA (type))
556 		return false;
557 	    }
558 	  return true;
559 	}
560     }
561   return false;
562 }
563 
564 /* For a METHOD in a Java class CTYPE, return true if
565    the parameter and return types are valid Java types.
566    Otherwise, print appropriate error messages, and return false.  */
567 
568 bool
check_java_method(tree method)569 check_java_method (tree method)
570 {
571   bool jerr = false;
572   tree arg_types = TYPE_ARG_TYPES (TREE_TYPE (method));
573   tree ret_type = TREE_TYPE (TREE_TYPE (method));
574 
575   if (!acceptable_java_type (ret_type))
576     {
577       error ("Java method %qD has non-Java return type %qT",
578 	     method, ret_type);
579       jerr = true;
580     }
581 
582   arg_types = TREE_CHAIN (arg_types);
583   if (DECL_HAS_IN_CHARGE_PARM_P (method))
584     arg_types = TREE_CHAIN (arg_types);
585   if (DECL_HAS_VTT_PARM_P (method))
586     arg_types = TREE_CHAIN (arg_types);
587 
588   for (; arg_types != NULL_TREE; arg_types = TREE_CHAIN (arg_types))
589     {
590       tree type = TREE_VALUE (arg_types);
591       if (!acceptable_java_type (type))
592 	{
593           if (type != error_mark_node)
594 	    error ("Java method %qD has non-Java parameter type %qT",
595 		   method, type);
596 	  jerr = true;
597 	}
598     }
599   return !jerr;
600 }
601 
602 /* Sanity check: report error if this function FUNCTION is not
603    really a member of the class (CTYPE) it is supposed to belong to.
604    TEMPLATE_PARMS is used to specify the template parameters of a member
605    template passed as FUNCTION_DECL. If the member template is passed as a
606    TEMPLATE_DECL, it can be NULL since the parameters can be extracted
607    from the declaration. If the function is not a function template, it
608    must be NULL.
609    It returns the original declaration for the function, NULL_TREE if
610    no declaration was found, error_mark_node if an error was emitted.  */
611 
612 tree
check_classfn(tree ctype,tree function,tree template_parms)613 check_classfn (tree ctype, tree function, tree template_parms)
614 {
615   int ix;
616   bool is_template;
617   tree pushed_scope;
618 
619   if (DECL_USE_TEMPLATE (function)
620       && !(TREE_CODE (function) == TEMPLATE_DECL
621 	   && DECL_TEMPLATE_SPECIALIZATION (function))
622       && DECL_MEMBER_TEMPLATE_P (DECL_TI_TEMPLATE (function)))
623     /* Since this is a specialization of a member template,
624        we're not going to find the declaration in the class.
625        For example, in:
626 
627 	 struct S { template <typename T> void f(T); };
628 	 template <> void S::f(int);
629 
630        we're not going to find `S::f(int)', but there's no
631        reason we should, either.  We let our callers know we didn't
632        find the method, but we don't complain.  */
633     return NULL_TREE;
634 
635   /* Basic sanity check: for a template function, the template parameters
636      either were not passed, or they are the same of DECL_TEMPLATE_PARMS.  */
637   if (TREE_CODE (function) == TEMPLATE_DECL)
638     {
639       if (template_parms
640 	  && !comp_template_parms (template_parms,
641 				   DECL_TEMPLATE_PARMS (function)))
642 	{
643 	  error ("template parameter lists provided don%'t match the "
644 		 "template parameters of %qD", function);
645 	  return error_mark_node;
646 	}
647       template_parms = DECL_TEMPLATE_PARMS (function);
648     }
649 
650   /* OK, is this a definition of a member template?  */
651   is_template = (template_parms != NULL_TREE);
652 
653   /* [temp.mem]
654 
655      A destructor shall not be a member template.  */
656   if (DECL_DESTRUCTOR_P (function) && is_template)
657     {
658       error ("destructor %qD declared as member template", function);
659       return error_mark_node;
660     }
661 
662   /* We must enter the scope here, because conversion operators are
663      named by target type, and type equivalence relies on typenames
664      resolving within the scope of CTYPE.  */
665   pushed_scope = push_scope (ctype);
666   ix = class_method_index_for_fn (complete_type (ctype), function);
667   if (ix >= 0)
668     {
669       vec<tree, va_gc> *methods = CLASSTYPE_METHOD_VEC (ctype);
670       tree fndecls, fndecl = 0;
671       bool is_conv_op;
672       const char *format = NULL;
673 
674       for (fndecls = (*methods)[ix];
675 	   fndecls; fndecls = OVL_NEXT (fndecls))
676 	{
677 	  tree p1, p2;
678 
679 	  fndecl = OVL_CURRENT (fndecls);
680 	  p1 = TYPE_ARG_TYPES (TREE_TYPE (function));
681 	  p2 = TYPE_ARG_TYPES (TREE_TYPE (fndecl));
682 
683 	  /* We cannot simply call decls_match because this doesn't
684 	     work for static member functions that are pretending to
685 	     be methods, and because the name may have been changed by
686 	     asm("new_name").  */
687 
688 	   /* Get rid of the this parameter on functions that become
689 	      static.  */
690 	  if (DECL_STATIC_FUNCTION_P (fndecl)
691 	      && TREE_CODE (TREE_TYPE (function)) == METHOD_TYPE)
692 	    p1 = TREE_CHAIN (p1);
693 
694 	  /* A member template definition only matches a member template
695 	     declaration.  */
696 	  if (is_template != (TREE_CODE (fndecl) == TEMPLATE_DECL))
697 	    continue;
698 
699 	  /* ref-qualifier or absence of same must match.  */
700 	  if (type_memfn_rqual (TREE_TYPE (function))
701 	      != type_memfn_rqual (TREE_TYPE (fndecl)))
702 	    continue;
703 
704 	  /* While finding a match, same types and params are not enough
705 	     if the function is versioned.  Also check version ("target")
706 	     attributes.  */
707 	  if (same_type_p (TREE_TYPE (TREE_TYPE (function)),
708 			   TREE_TYPE (TREE_TYPE (fndecl)))
709 	      && compparms (p1, p2)
710 	      && !targetm.target_option.function_versions (function, fndecl)
711 	      && (!is_template
712 		  || comp_template_parms (template_parms,
713 					  DECL_TEMPLATE_PARMS (fndecl)))
714 	      && (DECL_TEMPLATE_SPECIALIZATION (function)
715 		  == DECL_TEMPLATE_SPECIALIZATION (fndecl))
716 	      && (!DECL_TEMPLATE_SPECIALIZATION (function)
717 		  || (DECL_TI_TEMPLATE (function)
718 		      == DECL_TI_TEMPLATE (fndecl))))
719 	    break;
720 	}
721       if (fndecls)
722 	{
723 	  if (pushed_scope)
724 	    pop_scope (pushed_scope);
725 	  return OVL_CURRENT (fndecls);
726 	}
727 
728       error_at (DECL_SOURCE_LOCATION (function),
729 		"prototype for %q#D does not match any in class %qT",
730 		function, ctype);
731       is_conv_op = DECL_CONV_FN_P (fndecl);
732 
733       if (is_conv_op)
734 	ix = CLASSTYPE_FIRST_CONVERSION_SLOT;
735       fndecls = (*methods)[ix];
736       while (fndecls)
737 	{
738 	  fndecl = OVL_CURRENT (fndecls);
739 	  fndecls = OVL_NEXT (fndecls);
740 
741 	  if (!fndecls && is_conv_op)
742 	    {
743 	      if (methods->length () > (size_t) ++ix)
744 		{
745 		  fndecls = (*methods)[ix];
746 		  if (!DECL_CONV_FN_P (OVL_CURRENT (fndecls)))
747 		    {
748 		      fndecls = NULL_TREE;
749 		      is_conv_op = false;
750 		    }
751 		}
752 	      else
753 		is_conv_op = false;
754 	    }
755 	  if (format)
756 	    format = "                %+#D";
757 	  else if (fndecls)
758 	    format = N_("candidates are: %+#D");
759 	  else
760 	    format = N_("candidate is: %+#D");
761 	  error (format, fndecl);
762 	}
763     }
764   else if (!COMPLETE_TYPE_P (ctype))
765     cxx_incomplete_type_error (function, ctype);
766   else
767     error ("no %q#D member function declared in class %qT",
768 	   function, ctype);
769 
770   if (pushed_scope)
771     pop_scope (pushed_scope);
772   return error_mark_node;
773 }
774 
775 /* DECL is a function with vague linkage.  Remember it so that at the
776    end of the translation unit we can decide whether or not to emit
777    it.  */
778 
779 void
note_vague_linkage_fn(tree decl)780 note_vague_linkage_fn (tree decl)
781 {
782   DECL_DEFER_OUTPUT (decl) = 1;
783   vec_safe_push (deferred_fns, decl);
784 }
785 
786 /* We have just processed the DECL, which is a static data member.
787    The other parameters are as for cp_finish_decl.  */
788 
789 void
finish_static_data_member_decl(tree decl,tree init,bool init_const_expr_p,tree asmspec_tree,int flags)790 finish_static_data_member_decl (tree decl,
791 				tree init, bool init_const_expr_p,
792 				tree asmspec_tree,
793 				int flags)
794 {
795   DECL_CONTEXT (decl) = current_class_type;
796 
797   /* We cannot call pushdecl here, because that would fill in the
798      TREE_CHAIN of our decl.  Instead, we modify cp_finish_decl to do
799      the right thing, namely, to put this decl out straight away.  */
800 
801   if (! processing_template_decl)
802     vec_safe_push (pending_statics, decl);
803 
804   if (LOCAL_CLASS_P (current_class_type)
805       /* We already complained about the template definition.  */
806       && !DECL_TEMPLATE_INSTANTIATION (decl))
807     permerror (input_location, "local class %q#T shall not have static data member %q#D",
808 	       current_class_type, decl);
809   else
810     for (tree t = current_class_type; TYPE_P (t);
811 	 t = CP_TYPE_CONTEXT (t))
812       if (TYPE_ANONYMOUS_P (t))
813 	{
814 	  if (permerror (DECL_SOURCE_LOCATION (decl),
815 			 "static data member %qD in unnamed class", decl))
816 	    inform (DECL_SOURCE_LOCATION (TYPE_NAME (t)),
817 		    "unnamed class defined here");
818 	  break;
819 	}
820 
821   DECL_IN_AGGR_P (decl) = 1;
822 
823   if (TREE_CODE (TREE_TYPE (decl)) == ARRAY_TYPE
824       && TYPE_DOMAIN (TREE_TYPE (decl)) == NULL_TREE)
825     SET_VAR_HAD_UNKNOWN_BOUND (decl);
826 
827   cp_finish_decl (decl, init, init_const_expr_p, asmspec_tree, flags);
828 }
829 
830 /* DECLARATOR and DECLSPECS correspond to a class member.  The other
831    parameters are as for cp_finish_decl.  Return the DECL for the
832    class member declared.  */
833 
834 tree
grokfield(const cp_declarator * declarator,cp_decl_specifier_seq * declspecs,tree init,bool init_const_expr_p,tree asmspec_tree,tree attrlist)835 grokfield (const cp_declarator *declarator,
836 	   cp_decl_specifier_seq *declspecs,
837 	   tree init, bool init_const_expr_p,
838 	   tree asmspec_tree,
839 	   tree attrlist)
840 {
841   tree value;
842   const char *asmspec = 0;
843   int flags;
844   tree name;
845 
846   if (init
847       && TREE_CODE (init) == TREE_LIST
848       && TREE_VALUE (init) == error_mark_node
849       && TREE_CHAIN (init) == NULL_TREE)
850     init = NULL_TREE;
851 
852   value = grokdeclarator (declarator, declspecs, FIELD, init != 0, &attrlist);
853   if (! value || value == error_mark_node)
854     /* friend or constructor went bad.  */
855     return error_mark_node;
856   if (TREE_TYPE (value) == error_mark_node)
857     return value;
858 
859   if (TREE_CODE (value) == TYPE_DECL && init)
860     {
861       error ("typedef %qD is initialized (use decltype instead)", value);
862       init = NULL_TREE;
863     }
864 
865   /* Pass friendly classes back.  */
866   if (value == void_type_node)
867     return value;
868 
869   /* Pass friend decls back.  */
870   if ((TREE_CODE (value) == FUNCTION_DECL
871        || TREE_CODE (value) == TEMPLATE_DECL)
872       && DECL_CONTEXT (value) != current_class_type)
873     return value;
874 
875   name = DECL_NAME (value);
876 
877   if (name != NULL_TREE)
878     {
879       if (TREE_CODE (name) == TEMPLATE_ID_EXPR)
880 	{
881 	  error ("explicit template argument list not allowed");
882 	  return error_mark_node;
883 	}
884 
885       if (IDENTIFIER_POINTER (name)[0] == '_'
886 	  && ! strcmp (IDENTIFIER_POINTER (name), "_vptr"))
887 	error ("member %qD conflicts with virtual function table field name",
888 	       value);
889     }
890 
891   /* Stash away type declarations.  */
892   if (TREE_CODE (value) == TYPE_DECL)
893     {
894       DECL_NONLOCAL (value) = 1;
895       DECL_CONTEXT (value) = current_class_type;
896 
897       if (attrlist)
898 	{
899 	  int attrflags = 0;
900 
901 	  /* If this is a typedef that names the class for linkage purposes
902 	     (7.1.3p8), apply any attributes directly to the type.  */
903 	  if (OVERLOAD_TYPE_P (TREE_TYPE (value))
904 	      && value == TYPE_NAME (TYPE_MAIN_VARIANT (TREE_TYPE (value))))
905 	    attrflags = ATTR_FLAG_TYPE_IN_PLACE;
906 
907 	  cplus_decl_attributes (&value, attrlist, attrflags);
908 	}
909 
910       if (decl_spec_seq_has_spec_p (declspecs, ds_typedef)
911           && TREE_TYPE (value) != error_mark_node
912           && TYPE_NAME (TYPE_MAIN_VARIANT (TREE_TYPE (value))) != value)
913 	set_underlying_type (value);
914 
915       /* It's important that push_template_decl below follows
916 	 set_underlying_type above so that the created template
917 	 carries the properly set type of VALUE.  */
918       if (processing_template_decl)
919 	value = push_template_decl (value);
920 
921       record_locally_defined_typedef (value);
922       return value;
923     }
924 
925   if (DECL_IN_AGGR_P (value))
926     {
927       error ("%qD is already defined in %qT", value, DECL_CONTEXT (value));
928       return void_type_node;
929     }
930 
931   if (asmspec_tree && asmspec_tree != error_mark_node)
932     asmspec = TREE_STRING_POINTER (asmspec_tree);
933 
934   if (init)
935     {
936       if (TREE_CODE (value) == FUNCTION_DECL)
937 	{
938 	  /* Initializers for functions are rejected early in the parser.
939 	     If we get here, it must be a pure specifier for a method.  */
940 	  if (init == ridpointers[(int)RID_DELETE])
941 	    {
942 	      DECL_DELETED_FN (value) = 1;
943 	      DECL_DECLARED_INLINE_P (value) = 1;
944 	      DECL_INITIAL (value) = error_mark_node;
945 	    }
946 	  else if (init == ridpointers[(int)RID_DEFAULT])
947 	    {
948 	      if (defaultable_fn_check (value))
949 		{
950 		  DECL_DEFAULTED_FN (value) = 1;
951 		  DECL_INITIALIZED_IN_CLASS_P (value) = 1;
952 		  DECL_DECLARED_INLINE_P (value) = 1;
953 		}
954 	    }
955 	  else if (TREE_CODE (init) == DEFAULT_ARG)
956 	    error ("invalid initializer for member function %qD", value);
957 	  else if (TREE_CODE (TREE_TYPE (value)) == METHOD_TYPE)
958 	    {
959 	      if (integer_zerop (init))
960 		DECL_PURE_VIRTUAL_P (value) = 1;
961 	      else if (error_operand_p (init))
962 		; /* An error has already been reported.  */
963 	      else
964 		error ("invalid initializer for member function %qD",
965 		       value);
966 	    }
967 	  else
968 	    {
969 	      gcc_assert (TREE_CODE (TREE_TYPE (value)) == FUNCTION_TYPE);
970 	      error ("initializer specified for static member function %qD",
971 		     value);
972 	    }
973 	}
974       else if (TREE_CODE (value) == FIELD_DECL)
975 	/* C++11 NSDMI, keep going.  */;
976       else if (!VAR_P (value))
977 	gcc_unreachable ();
978     }
979 
980   if (processing_template_decl && VAR_OR_FUNCTION_DECL_P (value))
981     {
982       value = push_template_decl (value);
983       if (error_operand_p (value))
984 	return error_mark_node;
985     }
986 
987   if (attrlist)
988     cplus_decl_attributes (&value, attrlist, 0);
989 
990   if (init && BRACE_ENCLOSED_INITIALIZER_P (init)
991       && CONSTRUCTOR_IS_DIRECT_INIT (init))
992     flags = LOOKUP_NORMAL;
993   else
994     flags = LOOKUP_IMPLICIT;
995 
996   switch (TREE_CODE (value))
997     {
998     case VAR_DECL:
999       finish_static_data_member_decl (value, init, init_const_expr_p,
1000 				      asmspec_tree, flags);
1001       return value;
1002 
1003     case FIELD_DECL:
1004       if (asmspec)
1005 	error ("%<asm%> specifiers are not permitted on non-static data members");
1006       if (DECL_INITIAL (value) == error_mark_node)
1007 	init = error_mark_node;
1008       cp_finish_decl (value, init, /*init_const_expr_p=*/false,
1009 		      NULL_TREE, flags);
1010       DECL_IN_AGGR_P (value) = 1;
1011       return value;
1012 
1013     case  FUNCTION_DECL:
1014       if (asmspec)
1015 	set_user_assembler_name (value, asmspec);
1016 
1017       cp_finish_decl (value,
1018 		      /*init=*/NULL_TREE,
1019 		      /*init_const_expr_p=*/false,
1020 		      asmspec_tree, flags);
1021 
1022       /* Pass friends back this way.  */
1023       if (DECL_FRIEND_P (value))
1024 	return void_type_node;
1025 
1026       DECL_IN_AGGR_P (value) = 1;
1027       return value;
1028 
1029     default:
1030       gcc_unreachable ();
1031     }
1032   return NULL_TREE;
1033 }
1034 
1035 /* Like `grokfield', but for bitfields.
1036    WIDTH is non-NULL for bit fields only, and is an INTEGER_CST node.  */
1037 
1038 tree
grokbitfield(const cp_declarator * declarator,cp_decl_specifier_seq * declspecs,tree width,tree attrlist)1039 grokbitfield (const cp_declarator *declarator,
1040 	      cp_decl_specifier_seq *declspecs, tree width,
1041 	      tree attrlist)
1042 {
1043   tree value = grokdeclarator (declarator, declspecs, BITFIELD, 0, &attrlist);
1044 
1045   if (value == error_mark_node)
1046     return NULL_TREE; /* friends went bad.  */
1047   if (TREE_TYPE (value) == error_mark_node)
1048     return value;
1049 
1050   /* Pass friendly classes back.  */
1051   if (VOID_TYPE_P (value))
1052     return void_type_node;
1053 
1054   if (!INTEGRAL_OR_ENUMERATION_TYPE_P (TREE_TYPE (value))
1055       && (POINTER_TYPE_P (value)
1056           || !dependent_type_p (TREE_TYPE (value))))
1057     {
1058       error ("bit-field %qD with non-integral type", value);
1059       return error_mark_node;
1060     }
1061 
1062   if (TREE_CODE (value) == TYPE_DECL)
1063     {
1064       error ("cannot declare %qD to be a bit-field type", value);
1065       return NULL_TREE;
1066     }
1067 
1068   /* Usually, finish_struct_1 catches bitfields with invalid types.
1069      But, in the case of bitfields with function type, we confuse
1070      ourselves into thinking they are member functions, so we must
1071      check here.  */
1072   if (TREE_CODE (value) == FUNCTION_DECL)
1073     {
1074       error ("cannot declare bit-field %qD with function type",
1075 	     DECL_NAME (value));
1076       return NULL_TREE;
1077     }
1078 
1079   if (DECL_IN_AGGR_P (value))
1080     {
1081       error ("%qD is already defined in the class %qT", value,
1082 	     DECL_CONTEXT (value));
1083       return void_type_node;
1084     }
1085 
1086   if (TREE_STATIC (value))
1087     {
1088       error ("static member %qD cannot be a bit-field", value);
1089       return NULL_TREE;
1090     }
1091   cp_finish_decl (value, NULL_TREE, false, NULL_TREE, 0);
1092 
1093   if (width != error_mark_node)
1094     {
1095       /* The width must be an integer type.  */
1096       if (!type_dependent_expression_p (width)
1097 	  && !INTEGRAL_OR_UNSCOPED_ENUMERATION_TYPE_P (TREE_TYPE (width)))
1098 	error ("width of bit-field %qD has non-integral type %qT", value,
1099 	       TREE_TYPE (width));
1100       DECL_INITIAL (value) = width;
1101       SET_DECL_C_BIT_FIELD (value);
1102     }
1103 
1104   DECL_IN_AGGR_P (value) = 1;
1105 
1106   if (attrlist)
1107     cplus_decl_attributes (&value, attrlist, /*flags=*/0);
1108 
1109   return value;
1110 }
1111 
1112 
1113 /* Returns true iff ATTR is an attribute which needs to be applied at
1114    instantiation time rather than template definition time.  */
1115 
1116 static bool
is_late_template_attribute(tree attr,tree decl)1117 is_late_template_attribute (tree attr, tree decl)
1118 {
1119   tree name = get_attribute_name (attr);
1120   tree args = TREE_VALUE (attr);
1121   const struct attribute_spec *spec = lookup_attribute_spec (name);
1122   tree arg;
1123 
1124   if (!spec)
1125     /* Unknown attribute.  */
1126     return false;
1127 
1128   /* Attribute weak handling wants to write out assembly right away.  */
1129   if (is_attribute_p ("weak", name))
1130     return true;
1131 
1132   /* Attribute unused is applied directly, as it appertains to
1133      decls. */
1134   if (is_attribute_p ("unused", name))
1135     return false;
1136 
1137   /* #pragma omp declare simd attribute needs to be always deferred.  */
1138   if (flag_openmp
1139       && is_attribute_p ("omp declare simd", name))
1140     return true;
1141 
1142   /* If any of the arguments are dependent expressions, we can't evaluate
1143      the attribute until instantiation time.  */
1144   for (arg = args; arg; arg = TREE_CHAIN (arg))
1145     {
1146       tree t = TREE_VALUE (arg);
1147 
1148       /* If the first attribute argument is an identifier, only consider
1149 	 second and following arguments.  Attributes like mode, format,
1150 	 cleanup and several target specific attributes aren't late
1151 	 just because they have an IDENTIFIER_NODE as first argument.  */
1152       if (arg == args && identifier_p (t))
1153 	continue;
1154 
1155       if (value_dependent_expression_p (t)
1156 	  || type_dependent_expression_p (t))
1157 	return true;
1158     }
1159 
1160   if (TREE_CODE (decl) == TYPE_DECL
1161       || TYPE_P (decl)
1162       || spec->type_required)
1163     {
1164       tree type = TYPE_P (decl) ? decl : TREE_TYPE (decl);
1165 
1166       /* We can't apply any attributes to a completely unknown type until
1167 	 instantiation time.  */
1168       enum tree_code code = TREE_CODE (type);
1169       if (code == TEMPLATE_TYPE_PARM
1170 	  || code == BOUND_TEMPLATE_TEMPLATE_PARM
1171 	  || code == TYPENAME_TYPE)
1172 	return true;
1173       /* Also defer most attributes on dependent types.  This is not
1174 	 necessary in all cases, but is the better default.  */
1175       else if (dependent_type_p (type)
1176 	       /* But attributes abi_tag and visibility specifically apply
1177 		  to templates.  */
1178 	       && !is_attribute_p ("abi_tag", name)
1179 	       && !is_attribute_p ("visibility", name))
1180 	return true;
1181       else
1182 	return false;
1183     }
1184   else
1185     return false;
1186 }
1187 
1188 /* ATTR_P is a list of attributes.  Remove any attributes which need to be
1189    applied at instantiation time and return them.  If IS_DEPENDENT is true,
1190    the declaration itself is dependent, so all attributes should be applied
1191    at instantiation time.  */
1192 
1193 static tree
splice_template_attributes(tree * attr_p,tree decl)1194 splice_template_attributes (tree *attr_p, tree decl)
1195 {
1196   tree *p = attr_p;
1197   tree late_attrs = NULL_TREE;
1198   tree *q = &late_attrs;
1199 
1200   if (!p)
1201     return NULL_TREE;
1202 
1203   for (; *p; )
1204     {
1205       if (is_late_template_attribute (*p, decl))
1206 	{
1207 	  ATTR_IS_DEPENDENT (*p) = 1;
1208 	  *q = *p;
1209 	  *p = TREE_CHAIN (*p);
1210 	  q = &TREE_CHAIN (*q);
1211 	  *q = NULL_TREE;
1212 	}
1213       else
1214 	p = &TREE_CHAIN (*p);
1215     }
1216 
1217   return late_attrs;
1218 }
1219 
1220 /* Remove any late attributes from the list in ATTR_P and attach them to
1221    DECL_P.  */
1222 
1223 static void
save_template_attributes(tree * attr_p,tree * decl_p)1224 save_template_attributes (tree *attr_p, tree *decl_p)
1225 {
1226   tree *q;
1227 
1228   if (attr_p && *attr_p == error_mark_node)
1229     return;
1230 
1231   tree late_attrs = splice_template_attributes (attr_p, *decl_p);
1232   if (!late_attrs)
1233     return;
1234 
1235   if (DECL_P (*decl_p))
1236     q = &DECL_ATTRIBUTES (*decl_p);
1237   else
1238     q = &TYPE_ATTRIBUTES (*decl_p);
1239 
1240   tree old_attrs = *q;
1241 
1242   /* Merge the late attributes at the beginning with the attribute
1243      list.  */
1244   late_attrs = merge_attributes (late_attrs, *q);
1245   *q = late_attrs;
1246 
1247   if (!DECL_P (*decl_p) && *decl_p == TYPE_MAIN_VARIANT (*decl_p))
1248     {
1249       /* We've added new attributes directly to the main variant, so
1250 	 now we need to update all of the other variants to include
1251 	 these new attributes.  */
1252       tree variant;
1253       for (variant = TYPE_NEXT_VARIANT (*decl_p); variant;
1254 	   variant = TYPE_NEXT_VARIANT (variant))
1255 	{
1256 	  gcc_assert (TYPE_ATTRIBUTES (variant) == old_attrs);
1257 	  TYPE_ATTRIBUTES (variant) = TYPE_ATTRIBUTES (*decl_p);
1258 	}
1259     }
1260 }
1261 
1262 /* Return true iff ATTRS are acceptable attributes to be applied in-place
1263    to a typedef which gives a previously anonymous class or enum a name for
1264    linkage purposes.  */
1265 
1266 bool
attributes_naming_typedef_ok(tree attrs)1267 attributes_naming_typedef_ok (tree attrs)
1268 {
1269   for (; attrs; attrs = TREE_CHAIN (attrs))
1270     {
1271       tree name = get_attribute_name (attrs);
1272       if (is_attribute_p ("vector_size", name))
1273 	return false;
1274     }
1275   return true;
1276 }
1277 
1278 /* Like reconstruct_complex_type, but handle also template trees.  */
1279 
1280 tree
cp_reconstruct_complex_type(tree type,tree bottom)1281 cp_reconstruct_complex_type (tree type, tree bottom)
1282 {
1283   tree inner, outer;
1284 
1285   if (TYPE_PTR_P (type))
1286     {
1287       inner = cp_reconstruct_complex_type (TREE_TYPE (type), bottom);
1288       outer = build_pointer_type_for_mode (inner, TYPE_MODE (type),
1289 					   TYPE_REF_CAN_ALIAS_ALL (type));
1290     }
1291   else if (TREE_CODE (type) == REFERENCE_TYPE)
1292     {
1293       inner = cp_reconstruct_complex_type (TREE_TYPE (type), bottom);
1294       outer = build_reference_type_for_mode (inner, TYPE_MODE (type),
1295 					     TYPE_REF_CAN_ALIAS_ALL (type));
1296     }
1297   else if (TREE_CODE (type) == ARRAY_TYPE)
1298     {
1299       inner = cp_reconstruct_complex_type (TREE_TYPE (type), bottom);
1300       outer = build_cplus_array_type (inner, TYPE_DOMAIN (type));
1301       /* Don't call cp_build_qualified_type on ARRAY_TYPEs, the
1302 	 element type qualification will be handled by the recursive
1303 	 cp_reconstruct_complex_type call and cp_build_qualified_type
1304 	 for ARRAY_TYPEs changes the element type.  */
1305       return outer;
1306     }
1307   else if (TREE_CODE (type) == FUNCTION_TYPE)
1308     {
1309       inner = cp_reconstruct_complex_type (TREE_TYPE (type), bottom);
1310       outer = build_function_type (inner, TYPE_ARG_TYPES (type));
1311       outer = apply_memfn_quals (outer,
1312 				 type_memfn_quals (type),
1313 				 type_memfn_rqual (type));
1314     }
1315   else if (TREE_CODE (type) == METHOD_TYPE)
1316     {
1317       inner = cp_reconstruct_complex_type (TREE_TYPE (type), bottom);
1318       /* The build_method_type_directly() routine prepends 'this' to argument list,
1319 	 so we must compensate by getting rid of it.  */
1320       outer
1321 	= build_method_type_directly
1322 	    (class_of_this_parm (type), inner,
1323 	     TREE_CHAIN (TYPE_ARG_TYPES (type)));
1324     }
1325   else if (TREE_CODE (type) == OFFSET_TYPE)
1326     {
1327       inner = cp_reconstruct_complex_type (TREE_TYPE (type), bottom);
1328       outer = build_offset_type (TYPE_OFFSET_BASETYPE (type), inner);
1329     }
1330   else
1331     return bottom;
1332 
1333   if (TYPE_ATTRIBUTES (type))
1334     outer = cp_build_type_attribute_variant (outer, TYPE_ATTRIBUTES (type));
1335   return cp_build_qualified_type (outer, cp_type_quals (type));
1336 }
1337 
1338 /* Replaces any constexpr expression that may be into the attributes
1339    arguments with their reduced value.  */
1340 
1341 static void
cp_check_const_attributes(tree attributes)1342 cp_check_const_attributes (tree attributes)
1343 {
1344   if (attributes == error_mark_node)
1345     return;
1346 
1347   tree attr;
1348   for (attr = attributes; attr; attr = TREE_CHAIN (attr))
1349     {
1350       tree arg;
1351       for (arg = TREE_VALUE (attr); arg; arg = TREE_CHAIN (arg))
1352 	{
1353 	  tree expr = TREE_VALUE (arg);
1354 	  if (EXPR_P (expr))
1355 	    TREE_VALUE (arg) = maybe_constant_value (expr);
1356 	}
1357     }
1358 }
1359 
1360 /* Return true if TYPE is an OpenMP mappable type.  */
1361 bool
cp_omp_mappable_type(tree type)1362 cp_omp_mappable_type (tree type)
1363 {
1364   /* Mappable type has to be complete.  */
1365   if (type == error_mark_node || !COMPLETE_TYPE_P (type))
1366     return false;
1367   /* Arrays have mappable type if the elements have mappable type.  */
1368   while (TREE_CODE (type) == ARRAY_TYPE)
1369     type = TREE_TYPE (type);
1370   /* A mappable type cannot contain virtual members.  */
1371   if (CLASS_TYPE_P (type) && CLASSTYPE_VTABLES (type))
1372     return false;
1373   /* All data members must be non-static.  */
1374   if (CLASS_TYPE_P (type))
1375     {
1376       tree field;
1377       for (field = TYPE_FIELDS (type); field; field = DECL_CHAIN (field))
1378 	if (TREE_CODE (field) == VAR_DECL)
1379 	  return false;
1380 	/* All fields must have mappable types.  */
1381 	else if (TREE_CODE (field) == FIELD_DECL
1382 		 && !cp_omp_mappable_type (TREE_TYPE (field)))
1383 	  return false;
1384     }
1385   return true;
1386 }
1387 
1388 /* Like decl_attributes, but handle C++ complexity.  */
1389 
1390 void
cplus_decl_attributes(tree * decl,tree attributes,int flags)1391 cplus_decl_attributes (tree *decl, tree attributes, int flags)
1392 {
1393   if (*decl == NULL_TREE || *decl == void_type_node
1394       || *decl == error_mark_node)
1395     return;
1396 
1397   /* Add implicit "omp declare target" attribute if requested.  */
1398   if (scope_chain->omp_declare_target_attribute
1399       && ((TREE_CODE (*decl) == VAR_DECL && TREE_STATIC (*decl))
1400 	  || TREE_CODE (*decl) == FUNCTION_DECL))
1401     {
1402       if (TREE_CODE (*decl) == VAR_DECL
1403 	  && DECL_CLASS_SCOPE_P (*decl))
1404 	error ("%q+D static data member inside of declare target directive",
1405 	       *decl);
1406       else if (TREE_CODE (*decl) == VAR_DECL
1407 	       && (DECL_FUNCTION_SCOPE_P (*decl)
1408 		   || (current_function_decl && !DECL_EXTERNAL (*decl))))
1409 	error ("%q+D in block scope inside of declare target directive",
1410 	       *decl);
1411       else if (!processing_template_decl
1412 	       && TREE_CODE (*decl) == VAR_DECL
1413 	       && !cp_omp_mappable_type (TREE_TYPE (*decl)))
1414 	error ("%q+D in declare target directive does not have mappable type",
1415 	       *decl);
1416       else
1417 	attributes = tree_cons (get_identifier ("omp declare target"),
1418 				NULL_TREE, attributes);
1419     }
1420 
1421   if (processing_template_decl)
1422     {
1423       if (check_for_bare_parameter_packs (attributes))
1424 	return;
1425 
1426       save_template_attributes (&attributes, decl);
1427     }
1428 
1429   cp_check_const_attributes (attributes);
1430 
1431   if (TREE_CODE (*decl) == TEMPLATE_DECL)
1432     decl = &DECL_TEMPLATE_RESULT (*decl);
1433 
1434   decl_attributes (decl, attributes, flags);
1435 
1436   if (TREE_CODE (*decl) == TYPE_DECL)
1437     SET_IDENTIFIER_TYPE_VALUE (DECL_NAME (*decl), TREE_TYPE (*decl));
1438 }
1439 
1440 /* Walks through the namespace- or function-scope anonymous union
1441    OBJECT, with the indicated TYPE, building appropriate VAR_DECLs.
1442    Returns one of the fields for use in the mangled name.  */
1443 
1444 static tree
build_anon_union_vars(tree type,tree object)1445 build_anon_union_vars (tree type, tree object)
1446 {
1447   tree main_decl = NULL_TREE;
1448   tree field;
1449 
1450   /* Rather than write the code to handle the non-union case,
1451      just give an error.  */
1452   if (TREE_CODE (type) != UNION_TYPE)
1453     {
1454       error ("anonymous struct not inside named type");
1455       return error_mark_node;
1456     }
1457 
1458   for (field = TYPE_FIELDS (type);
1459        field != NULL_TREE;
1460        field = DECL_CHAIN (field))
1461     {
1462       tree decl;
1463       tree ref;
1464 
1465       if (DECL_ARTIFICIAL (field))
1466 	continue;
1467       if (TREE_CODE (field) != FIELD_DECL)
1468 	{
1469 	  permerror (input_location, "%q+#D invalid; an anonymous union can only "
1470 		     "have non-static data members", field);
1471 	  continue;
1472 	}
1473 
1474       if (TREE_PRIVATE (field))
1475 	permerror (input_location, "private member %q+#D in anonymous union", field);
1476       else if (TREE_PROTECTED (field))
1477 	permerror (input_location, "protected member %q+#D in anonymous union", field);
1478 
1479       if (processing_template_decl)
1480 	ref = build_min_nt_loc (UNKNOWN_LOCATION, COMPONENT_REF, object,
1481 				DECL_NAME (field), NULL_TREE);
1482       else
1483 	ref = build_class_member_access_expr (object, field, NULL_TREE,
1484 					      false, tf_warning_or_error);
1485 
1486       if (DECL_NAME (field))
1487 	{
1488 	  tree base;
1489 
1490 	  decl = build_decl (input_location,
1491 			     VAR_DECL, DECL_NAME (field), TREE_TYPE (field));
1492 	  DECL_ANON_UNION_VAR_P (decl) = 1;
1493 	  DECL_ARTIFICIAL (decl) = 1;
1494 
1495 	  base = get_base_address (object);
1496 	  TREE_PUBLIC (decl) = TREE_PUBLIC (base);
1497 	  TREE_STATIC (decl) = TREE_STATIC (base);
1498 	  DECL_EXTERNAL (decl) = DECL_EXTERNAL (base);
1499 
1500 	  SET_DECL_VALUE_EXPR (decl, ref);
1501 	  DECL_HAS_VALUE_EXPR_P (decl) = 1;
1502 
1503 	  decl = pushdecl (decl);
1504 	}
1505       else if (ANON_AGGR_TYPE_P (TREE_TYPE (field)))
1506 	decl = build_anon_union_vars (TREE_TYPE (field), ref);
1507       else
1508 	decl = 0;
1509 
1510       if (main_decl == NULL_TREE)
1511 	main_decl = decl;
1512     }
1513 
1514   return main_decl;
1515 }
1516 
1517 /* Finish off the processing of a UNION_TYPE structure.  If the union is an
1518    anonymous union, then all members must be laid out together.  PUBLIC_P
1519    is nonzero if this union is not declared static.  */
1520 
1521 void
finish_anon_union(tree anon_union_decl)1522 finish_anon_union (tree anon_union_decl)
1523 {
1524   tree type;
1525   tree main_decl;
1526   bool public_p;
1527 
1528   if (anon_union_decl == error_mark_node)
1529     return;
1530 
1531   type = TREE_TYPE (anon_union_decl);
1532   public_p = TREE_PUBLIC (anon_union_decl);
1533 
1534   /* The VAR_DECL's context is the same as the TYPE's context.  */
1535   DECL_CONTEXT (anon_union_decl) = DECL_CONTEXT (TYPE_NAME (type));
1536 
1537   if (TYPE_FIELDS (type) == NULL_TREE)
1538     return;
1539 
1540   if (public_p)
1541     {
1542       error ("namespace-scope anonymous aggregates must be static");
1543       return;
1544     }
1545 
1546   main_decl = build_anon_union_vars (type, anon_union_decl);
1547   if (main_decl == error_mark_node)
1548     return;
1549   if (main_decl == NULL_TREE)
1550     {
1551       warning (0, "anonymous union with no members");
1552       return;
1553     }
1554 
1555   if (!processing_template_decl)
1556     {
1557       /* Use main_decl to set the mangled name.  */
1558       DECL_NAME (anon_union_decl) = DECL_NAME (main_decl);
1559       maybe_commonize_var (anon_union_decl);
1560       if (TREE_STATIC (anon_union_decl) || DECL_EXTERNAL (anon_union_decl))
1561 	mangle_decl (anon_union_decl);
1562       DECL_NAME (anon_union_decl) = NULL_TREE;
1563     }
1564 
1565   pushdecl (anon_union_decl);
1566   cp_finish_decl (anon_union_decl, NULL_TREE, false, NULL_TREE, 0);
1567 }
1568 
1569 /* Auxiliary functions to make type signatures for
1570    `operator new' and `operator delete' correspond to
1571    what compiler will be expecting.  */
1572 
1573 tree
coerce_new_type(tree type)1574 coerce_new_type (tree type)
1575 {
1576   int e = 0;
1577   tree args = TYPE_ARG_TYPES (type);
1578 
1579   gcc_assert (TREE_CODE (type) == FUNCTION_TYPE);
1580 
1581   if (!same_type_p (TREE_TYPE (type), ptr_type_node))
1582     {
1583       e = 1;
1584       error ("%<operator new%> must return type %qT", ptr_type_node);
1585     }
1586 
1587   if (args && args != void_list_node)
1588     {
1589       if (TREE_PURPOSE (args))
1590 	{
1591 	  /* [basic.stc.dynamic.allocation]
1592 
1593 	     The first parameter shall not have an associated default
1594 	     argument.  */
1595 	  error ("the first parameter of %<operator new%> cannot "
1596 		 "have a default argument");
1597 	  /* Throw away the default argument.  */
1598 	  TREE_PURPOSE (args) = NULL_TREE;
1599 	}
1600 
1601       if (!same_type_p (TREE_VALUE (args), size_type_node))
1602 	{
1603 	  e = 2;
1604 	  args = TREE_CHAIN (args);
1605 	}
1606     }
1607   else
1608     e = 2;
1609 
1610   if (e == 2)
1611     permerror (input_location, "%<operator new%> takes type %<size_t%> (%qT) "
1612 	       "as first parameter", size_type_node);
1613 
1614   switch (e)
1615   {
1616     case 2:
1617       args = tree_cons (NULL_TREE, size_type_node, args);
1618       /* Fall through.  */
1619     case 1:
1620       type = build_exception_variant
1621 	      (build_function_type (ptr_type_node, args),
1622 	       TYPE_RAISES_EXCEPTIONS (type));
1623       /* Fall through.  */
1624     default:;
1625   }
1626   return type;
1627 }
1628 
1629 tree
coerce_delete_type(tree type)1630 coerce_delete_type (tree type)
1631 {
1632   int e = 0;
1633   tree args = TYPE_ARG_TYPES (type);
1634 
1635   gcc_assert (TREE_CODE (type) == FUNCTION_TYPE);
1636 
1637   if (!same_type_p (TREE_TYPE (type), void_type_node))
1638     {
1639       e = 1;
1640       error ("%<operator delete%> must return type %qT", void_type_node);
1641     }
1642 
1643   if (!args || args == void_list_node
1644       || !same_type_p (TREE_VALUE (args), ptr_type_node))
1645     {
1646       e = 2;
1647       if (args && args != void_list_node)
1648 	args = TREE_CHAIN (args);
1649       error ("%<operator delete%> takes type %qT as first parameter",
1650 	     ptr_type_node);
1651     }
1652   switch (e)
1653   {
1654     case 2:
1655       args = tree_cons (NULL_TREE, ptr_type_node, args);
1656       /* Fall through.  */
1657     case 1:
1658       type = build_exception_variant
1659 	      (build_function_type (void_type_node, args),
1660 	       TYPE_RAISES_EXCEPTIONS (type));
1661       /* Fall through.  */
1662     default:;
1663   }
1664 
1665   return type;
1666 }
1667 
1668 /* DECL is a VAR_DECL for a vtable: walk through the entries in the vtable
1669    and mark them as needed.  */
1670 
1671 static void
mark_vtable_entries(tree decl)1672 mark_vtable_entries (tree decl)
1673 {
1674   tree fnaddr;
1675   unsigned HOST_WIDE_INT idx;
1676 
1677   FOR_EACH_CONSTRUCTOR_VALUE (CONSTRUCTOR_ELTS (DECL_INITIAL (decl)),
1678 			      idx, fnaddr)
1679     {
1680       tree fn;
1681 
1682       STRIP_NOPS (fnaddr);
1683 
1684       if (TREE_CODE (fnaddr) != ADDR_EXPR
1685 	  && TREE_CODE (fnaddr) != FDESC_EXPR)
1686 	/* This entry is an offset: a virtual base class offset, a
1687 	   virtual call offset, an RTTI offset, etc.  */
1688 	continue;
1689 
1690       fn = TREE_OPERAND (fnaddr, 0);
1691       TREE_ADDRESSABLE (fn) = 1;
1692       /* When we don't have vcall offsets, we output thunks whenever
1693 	 we output the vtables that contain them.  With vcall offsets,
1694 	 we know all the thunks we'll need when we emit a virtual
1695 	 function, so we emit the thunks there instead.  */
1696       if (DECL_THUNK_P (fn))
1697 	use_thunk (fn, /*emit_p=*/0);
1698       mark_used (fn);
1699     }
1700 }
1701 
1702 /* Set DECL up to have the closest approximation of "initialized common"
1703    linkage available.  */
1704 
1705 void
comdat_linkage(tree decl)1706 comdat_linkage (tree decl)
1707 {
1708   if (flag_weak)
1709     make_decl_one_only (decl, cxx_comdat_group (decl));
1710   else if (TREE_CODE (decl) == FUNCTION_DECL
1711 	   || (VAR_P (decl) && DECL_ARTIFICIAL (decl)))
1712     /* We can just emit function and compiler-generated variables
1713        statically; having multiple copies is (for the most part) only
1714        a waste of space.
1715 
1716        There are two correctness issues, however: the address of a
1717        template instantiation with external linkage should be the
1718        same, independent of what translation unit asks for the
1719        address, and this will not hold when we emit multiple copies of
1720        the function.  However, there's little else we can do.
1721 
1722        Also, by default, the typeinfo implementation assumes that
1723        there will be only one copy of the string used as the name for
1724        each type.  Therefore, if weak symbols are unavailable, the
1725        run-time library should perform a more conservative check; it
1726        should perform a string comparison, rather than an address
1727        comparison.  */
1728     TREE_PUBLIC (decl) = 0;
1729   else
1730     {
1731       /* Static data member template instantiations, however, cannot
1732 	 have multiple copies.  */
1733       if (DECL_INITIAL (decl) == 0
1734 	  || DECL_INITIAL (decl) == error_mark_node)
1735 	DECL_COMMON (decl) = 1;
1736       else if (EMPTY_CONSTRUCTOR_P (DECL_INITIAL (decl)))
1737 	{
1738 	  DECL_COMMON (decl) = 1;
1739 	  DECL_INITIAL (decl) = error_mark_node;
1740 	}
1741       else if (!DECL_EXPLICIT_INSTANTIATION (decl))
1742 	{
1743 	  /* We can't do anything useful; leave vars for explicit
1744 	     instantiation.  */
1745 	  DECL_EXTERNAL (decl) = 1;
1746 	  DECL_NOT_REALLY_EXTERN (decl) = 0;
1747 	}
1748     }
1749 
1750   DECL_COMDAT (decl) = 1;
1751 }
1752 
1753 /* For win32 we also want to put explicit instantiations in
1754    linkonce sections, so that they will be merged with implicit
1755    instantiations; otherwise we get duplicate symbol errors.
1756    For Darwin we do not want explicit instantiations to be
1757    linkonce.  */
1758 
1759 void
maybe_make_one_only(tree decl)1760 maybe_make_one_only (tree decl)
1761 {
1762   /* We used to say that this was not necessary on targets that support weak
1763      symbols, because the implicit instantiations will defer to the explicit
1764      one.  However, that's not actually the case in SVR4; a strong definition
1765      after a weak one is an error.  Also, not making explicit
1766      instantiations one_only means that we can end up with two copies of
1767      some template instantiations.  */
1768   if (! flag_weak)
1769     return;
1770 
1771   /* We can't set DECL_COMDAT on functions, or cp_finish_file will think
1772      we can get away with not emitting them if they aren't used.  We need
1773      to for variables so that cp_finish_decl will update their linkage,
1774      because their DECL_INITIAL may not have been set properly yet.  */
1775 
1776   if (!TARGET_WEAK_NOT_IN_ARCHIVE_TOC
1777       || (! DECL_EXPLICIT_INSTANTIATION (decl)
1778 	  && ! DECL_TEMPLATE_SPECIALIZATION (decl)))
1779     {
1780       make_decl_one_only (decl, cxx_comdat_group (decl));
1781 
1782       if (VAR_P (decl))
1783 	{
1784           varpool_node *node = varpool_node_for_decl (decl);
1785 	  DECL_COMDAT (decl) = 1;
1786 	  /* Mark it needed so we don't forget to emit it.  */
1787           node->forced_by_abi = true;
1788 	  TREE_USED (decl) = 1;
1789 	}
1790     }
1791 }
1792 
1793 /* Returns true iff DECL, a FUNCTION_DECL or VAR_DECL, has vague linkage.
1794    This predicate will give the right answer during parsing of the
1795    function, which other tests may not.  */
1796 
1797 bool
vague_linkage_p(tree decl)1798 vague_linkage_p (tree decl)
1799 {
1800   /* Unfortunately, import_export_decl has not always been called
1801      before the function is processed, so we cannot simply check
1802      DECL_COMDAT.  */
1803   return (DECL_COMDAT (decl)
1804 	  || (((TREE_CODE (decl) == FUNCTION_DECL
1805 		&& DECL_DECLARED_INLINE_P (decl))
1806 	       || (DECL_LANG_SPECIFIC (decl)
1807 		   && DECL_TEMPLATE_INSTANTIATION (decl)))
1808 	      && TREE_PUBLIC (decl)));
1809 }
1810 
1811 /* Determine whether or not we want to specifically import or export CTYPE,
1812    using various heuristics.  */
1813 
1814 static void
import_export_class(tree ctype)1815 import_export_class (tree ctype)
1816 {
1817   /* -1 for imported, 1 for exported.  */
1818   int import_export = 0;
1819 
1820   /* It only makes sense to call this function at EOF.  The reason is
1821      that this function looks at whether or not the first non-inline
1822      non-abstract virtual member function has been defined in this
1823      translation unit.  But, we can't possibly know that until we've
1824      seen the entire translation unit.  */
1825   gcc_assert (at_eof);
1826 
1827   if (CLASSTYPE_INTERFACE_KNOWN (ctype))
1828     return;
1829 
1830   /* If MULTIPLE_SYMBOL_SPACES is set and we saw a #pragma interface,
1831      we will have CLASSTYPE_INTERFACE_ONLY set but not
1832      CLASSTYPE_INTERFACE_KNOWN.  In that case, we don't want to use this
1833      heuristic because someone will supply a #pragma implementation
1834      elsewhere, and deducing it here would produce a conflict.  */
1835   if (CLASSTYPE_INTERFACE_ONLY (ctype))
1836     return;
1837 
1838   if (lookup_attribute ("dllimport", TYPE_ATTRIBUTES (ctype)))
1839     import_export = -1;
1840   else if (lookup_attribute ("dllexport", TYPE_ATTRIBUTES (ctype)))
1841     import_export = 1;
1842   else if (CLASSTYPE_IMPLICIT_INSTANTIATION (ctype)
1843 	   && !flag_implicit_templates)
1844     /* For a template class, without -fimplicit-templates, check the
1845        repository.  If the virtual table is assigned to this
1846        translation unit, then export the class; otherwise, import
1847        it.  */
1848       import_export = repo_export_class_p (ctype) ? 1 : -1;
1849   else if (TYPE_POLYMORPHIC_P (ctype))
1850     {
1851       /* The ABI specifies that the virtual table and associated
1852 	 information are emitted with the key method, if any.  */
1853       tree method = CLASSTYPE_KEY_METHOD (ctype);
1854       /* If weak symbol support is not available, then we must be
1855 	 careful not to emit the vtable when the key function is
1856 	 inline.  An inline function can be defined in multiple
1857 	 translation units.  If we were to emit the vtable in each
1858 	 translation unit containing a definition, we would get
1859 	 multiple definition errors at link-time.  */
1860       if (method && (flag_weak || ! DECL_DECLARED_INLINE_P (method)))
1861 	import_export = (DECL_REALLY_EXTERN (method) ? -1 : 1);
1862     }
1863 
1864   /* When MULTIPLE_SYMBOL_SPACES is set, we cannot count on seeing
1865      a definition anywhere else.  */
1866   if (MULTIPLE_SYMBOL_SPACES && import_export == -1)
1867     import_export = 0;
1868 
1869   /* Allow back ends the chance to overrule the decision.  */
1870   if (targetm.cxx.import_export_class)
1871     import_export = targetm.cxx.import_export_class (ctype, import_export);
1872 
1873   if (import_export)
1874     {
1875       SET_CLASSTYPE_INTERFACE_KNOWN (ctype);
1876       CLASSTYPE_INTERFACE_ONLY (ctype) = (import_export < 0);
1877     }
1878 }
1879 
1880 /* Return true if VAR has already been provided to the back end; in that
1881    case VAR should not be modified further by the front end.  */
1882 static bool
var_finalized_p(tree var)1883 var_finalized_p (tree var)
1884 {
1885   return varpool_node_for_decl (var)->definition;
1886 }
1887 
1888 /* DECL is a VAR_DECL or FUNCTION_DECL which, for whatever reason,
1889    must be emitted in this translation unit.  Mark it as such.  */
1890 
1891 void
mark_needed(tree decl)1892 mark_needed (tree decl)
1893 {
1894   TREE_USED (decl) = 1;
1895   if (TREE_CODE (decl) == FUNCTION_DECL)
1896     {
1897       /* Extern inline functions don't become needed when referenced.
1898 	 If we know a method will be emitted in other TU and no new
1899 	 functions can be marked reachable, just use the external
1900 	 definition.  */
1901       struct cgraph_node *node = cgraph_get_create_node (decl);
1902       node->forced_by_abi = true;
1903 
1904       /* #pragma interface and -frepo code can call mark_needed for
1905           maybe-in-charge 'tors; mark the clones as well.  */
1906       tree clone;
1907       FOR_EACH_CLONE (clone, decl)
1908 	mark_needed (clone);
1909     }
1910   else if (TREE_CODE (decl) == VAR_DECL)
1911     {
1912       varpool_node *node = varpool_node_for_decl (decl);
1913       /* C++ frontend use mark_decl_references to force COMDAT variables
1914          to be output that might appear dead otherwise.  */
1915       node->forced_by_abi = true;
1916     }
1917 }
1918 
1919 /* DECL is either a FUNCTION_DECL or a VAR_DECL.  This function
1920    returns true if a definition of this entity should be provided in
1921    this object file.  Callers use this function to determine whether
1922    or not to let the back end know that a definition of DECL is
1923    available in this translation unit.  */
1924 
1925 bool
decl_needed_p(tree decl)1926 decl_needed_p (tree decl)
1927 {
1928   gcc_assert (VAR_OR_FUNCTION_DECL_P (decl));
1929   /* This function should only be called at the end of the translation
1930      unit.  We cannot be sure of whether or not something will be
1931      COMDAT until that point.  */
1932   gcc_assert (at_eof);
1933 
1934   /* All entities with external linkage that are not COMDAT should be
1935      emitted; they may be referred to from other object files.  */
1936   if (TREE_PUBLIC (decl) && !DECL_COMDAT (decl))
1937     return true;
1938   /* If this entity was used, let the back end see it; it will decide
1939      whether or not to emit it into the object file.  */
1940   if (TREE_USED (decl))
1941       return true;
1942   /* Functions marked "dllexport" must be emitted so that they are
1943      visible to other DLLs.  */
1944   if (flag_keep_inline_dllexport
1945       && lookup_attribute ("dllexport", DECL_ATTRIBUTES (decl)))
1946     return true;
1947   /* Otherwise, DECL does not need to be emitted -- yet.  A subsequent
1948      reference to DECL might cause it to be emitted later.  */
1949   return false;
1950 }
1951 
1952 /* If necessary, write out the vtables for the dynamic class CTYPE.
1953    Returns true if any vtables were emitted.  */
1954 
1955 static bool
maybe_emit_vtables(tree ctype)1956 maybe_emit_vtables (tree ctype)
1957 {
1958   tree vtbl;
1959   tree primary_vtbl;
1960   int needed = 0;
1961   varpool_node *current = NULL, *last = NULL;
1962 
1963   /* If the vtables for this class have already been emitted there is
1964      nothing more to do.  */
1965   primary_vtbl = CLASSTYPE_VTABLES (ctype);
1966   if (var_finalized_p (primary_vtbl))
1967     return false;
1968   /* Ignore dummy vtables made by get_vtable_decl.  */
1969   if (TREE_TYPE (primary_vtbl) == void_type_node)
1970     return false;
1971 
1972   /* On some targets, we cannot determine the key method until the end
1973      of the translation unit -- which is when this function is
1974      called.  */
1975   if (!targetm.cxx.key_method_may_be_inline ())
1976     determine_key_method (ctype);
1977 
1978   /* See if any of the vtables are needed.  */
1979   for (vtbl = CLASSTYPE_VTABLES (ctype); vtbl; vtbl = DECL_CHAIN (vtbl))
1980     {
1981       import_export_decl (vtbl);
1982       if (DECL_NOT_REALLY_EXTERN (vtbl) && decl_needed_p (vtbl))
1983 	needed = 1;
1984     }
1985   if (!needed)
1986     {
1987       /* If the references to this class' vtables are optimized away,
1988 	 still emit the appropriate debugging information.  See
1989 	 dfs_debug_mark.  */
1990       if (DECL_COMDAT (primary_vtbl)
1991 	  && CLASSTYPE_DEBUG_REQUESTED (ctype))
1992 	note_debug_info_needed (ctype);
1993       return false;
1994     }
1995 
1996   /* The ABI requires that we emit all of the vtables if we emit any
1997      of them.  */
1998   for (vtbl = CLASSTYPE_VTABLES (ctype); vtbl; vtbl = DECL_CHAIN (vtbl))
1999     {
2000       /* Mark entities references from the virtual table as used.  */
2001       mark_vtable_entries (vtbl);
2002 
2003       if (TREE_TYPE (DECL_INITIAL (vtbl)) == 0)
2004 	{
2005 	  vec<tree, va_gc> *cleanups = NULL;
2006 	  tree expr = store_init_value (vtbl, DECL_INITIAL (vtbl), &cleanups,
2007 					LOOKUP_NORMAL);
2008 
2009 	  /* It had better be all done at compile-time.  */
2010 	  gcc_assert (!expr && !cleanups);
2011 	}
2012 
2013       /* Write it out.  */
2014       DECL_EXTERNAL (vtbl) = 0;
2015       rest_of_decl_compilation (vtbl, 1, 1);
2016 
2017       /* Because we're only doing syntax-checking, we'll never end up
2018 	 actually marking the variable as written.  */
2019       if (flag_syntax_only)
2020 	TREE_ASM_WRITTEN (vtbl) = 1;
2021       else if (DECL_ONE_ONLY (vtbl))
2022 	{
2023 	  current = varpool_node_for_decl (vtbl);
2024 	  if (last)
2025 	    symtab_add_to_same_comdat_group (current, last);
2026 	  last = current;
2027 	}
2028     }
2029 
2030   /* Since we're writing out the vtable here, also write the debug
2031      info.  */
2032   note_debug_info_needed (ctype);
2033 
2034   return true;
2035 }
2036 
2037 /* A special return value from type_visibility meaning internal
2038    linkage.  */
2039 
2040 enum { VISIBILITY_ANON = VISIBILITY_INTERNAL+1 };
2041 
2042 /* walk_tree helper function for type_visibility.  */
2043 
2044 static tree
min_vis_r(tree * tp,int * walk_subtrees,void * data)2045 min_vis_r (tree *tp, int *walk_subtrees, void *data)
2046 {
2047   int *vis_p = (int *)data;
2048   if (! TYPE_P (*tp))
2049     {
2050       *walk_subtrees = 0;
2051     }
2052   else if (OVERLOAD_TYPE_P (*tp)
2053 	   && !TREE_PUBLIC (TYPE_MAIN_DECL (*tp)))
2054     {
2055       *vis_p = VISIBILITY_ANON;
2056       return *tp;
2057     }
2058   else if (CLASS_TYPE_P (*tp)
2059 	   && CLASSTYPE_VISIBILITY (*tp) > *vis_p)
2060     *vis_p = CLASSTYPE_VISIBILITY (*tp);
2061   return NULL;
2062 }
2063 
2064 /* Returns the visibility of TYPE, which is the minimum visibility of its
2065    component types.  */
2066 
2067 static int
type_visibility(tree type)2068 type_visibility (tree type)
2069 {
2070   int vis = VISIBILITY_DEFAULT;
2071   cp_walk_tree_without_duplicates (&type, min_vis_r, &vis);
2072   return vis;
2073 }
2074 
2075 /* Limit the visibility of DECL to VISIBILITY, if not explicitly
2076    specified (or if VISIBILITY is static).  If TMPL is true, this
2077    constraint is for a template argument, and takes precedence
2078    over explicitly-specified visibility on the template.  */
2079 
2080 static void
constrain_visibility(tree decl,int visibility,bool tmpl)2081 constrain_visibility (tree decl, int visibility, bool tmpl)
2082 {
2083   if (visibility == VISIBILITY_ANON)
2084     {
2085       /* extern "C" declarations aren't affected by the anonymous
2086 	 namespace.  */
2087       if (!DECL_EXTERN_C_P (decl))
2088 	{
2089 	  TREE_PUBLIC (decl) = 0;
2090 	  DECL_WEAK (decl) = 0;
2091 	  DECL_COMMON (decl) = 0;
2092 	  DECL_COMDAT_GROUP (decl) = NULL_TREE;
2093 	  DECL_INTERFACE_KNOWN (decl) = 1;
2094 	  if (DECL_LANG_SPECIFIC (decl))
2095 	    DECL_NOT_REALLY_EXTERN (decl) = 1;
2096 	}
2097     }
2098   else if (visibility > DECL_VISIBILITY (decl)
2099 	   && (tmpl || !DECL_VISIBILITY_SPECIFIED (decl)))
2100     {
2101       DECL_VISIBILITY (decl) = (enum symbol_visibility) visibility;
2102       /* This visibility was not specified.  */
2103       DECL_VISIBILITY_SPECIFIED (decl) = false;
2104     }
2105 }
2106 
2107 /* Constrain the visibility of DECL based on the visibility of its template
2108    arguments.  */
2109 
2110 static void
constrain_visibility_for_template(tree decl,tree targs)2111 constrain_visibility_for_template (tree decl, tree targs)
2112 {
2113   /* If this is a template instantiation, check the innermost
2114      template args for visibility constraints.  The outer template
2115      args are covered by the class check.  */
2116   tree args = INNERMOST_TEMPLATE_ARGS (targs);
2117   int i;
2118   for (i = TREE_VEC_LENGTH (args); i > 0; --i)
2119     {
2120       int vis = 0;
2121 
2122       tree arg = TREE_VEC_ELT (args, i-1);
2123       if (TYPE_P (arg))
2124 	vis = type_visibility (arg);
2125       else if (TREE_TYPE (arg) && POINTER_TYPE_P (TREE_TYPE (arg)))
2126 	{
2127 	  STRIP_NOPS (arg);
2128 	  if (TREE_CODE (arg) == ADDR_EXPR)
2129 	    arg = TREE_OPERAND (arg, 0);
2130 	  if (VAR_OR_FUNCTION_DECL_P (arg))
2131 	    {
2132 	      if (! TREE_PUBLIC (arg))
2133 		vis = VISIBILITY_ANON;
2134 	      else
2135 		vis = DECL_VISIBILITY (arg);
2136 	    }
2137 	}
2138       if (vis)
2139 	constrain_visibility (decl, vis, true);
2140     }
2141 }
2142 
2143 /* Like c_determine_visibility, but with additional C++-specific
2144    behavior.
2145 
2146    Function-scope entities can rely on the function's visibility because
2147    it is set in start_preparsed_function.
2148 
2149    Class-scope entities cannot rely on the class's visibility until the end
2150    of the enclosing class definition.
2151 
2152    Note that because namespaces have multiple independent definitions,
2153    namespace visibility is handled elsewhere using the #pragma visibility
2154    machinery rather than by decorating the namespace declaration.
2155 
2156    The goal is for constraints from the type to give a diagnostic, and
2157    other constraints to be applied silently.  */
2158 
2159 void
determine_visibility(tree decl)2160 determine_visibility (tree decl)
2161 {
2162   tree class_type = NULL_TREE;
2163   bool use_template;
2164   bool orig_visibility_specified;
2165   enum symbol_visibility orig_visibility;
2166 
2167   /* Remember that all decls get VISIBILITY_DEFAULT when built.  */
2168 
2169   /* Only relevant for names with external linkage.  */
2170   if (!TREE_PUBLIC (decl))
2171     return;
2172 
2173   /* Cloned constructors and destructors get the same visibility as
2174      the underlying function.  That should be set up in
2175      maybe_clone_body.  */
2176   gcc_assert (!DECL_CLONED_FUNCTION_P (decl));
2177 
2178   orig_visibility_specified = DECL_VISIBILITY_SPECIFIED (decl);
2179   orig_visibility = DECL_VISIBILITY (decl);
2180 
2181   if (TREE_CODE (decl) == TYPE_DECL)
2182     {
2183       if (CLASS_TYPE_P (TREE_TYPE (decl)))
2184 	use_template = CLASSTYPE_USE_TEMPLATE (TREE_TYPE (decl));
2185       else if (TYPE_TEMPLATE_INFO (TREE_TYPE (decl)))
2186 	use_template = 1;
2187       else
2188 	use_template = 0;
2189     }
2190   else if (DECL_LANG_SPECIFIC (decl))
2191     use_template = DECL_USE_TEMPLATE (decl);
2192   else
2193     use_template = 0;
2194 
2195   /* If DECL is a member of a class, visibility specifiers on the
2196      class can influence the visibility of the DECL.  */
2197   if (DECL_CLASS_SCOPE_P (decl))
2198     class_type = DECL_CONTEXT (decl);
2199   else
2200     {
2201       /* Not a class member.  */
2202 
2203       /* Virtual tables have DECL_CONTEXT set to their associated class,
2204 	 so they are automatically handled above.  */
2205       gcc_assert (!VAR_P (decl)
2206 		  || !DECL_VTABLE_OR_VTT_P (decl));
2207 
2208       if (DECL_FUNCTION_SCOPE_P (decl) && ! DECL_VISIBILITY_SPECIFIED (decl))
2209 	{
2210 	  /* Local statics and classes get the visibility of their
2211 	     containing function by default, except that
2212 	     -fvisibility-inlines-hidden doesn't affect them.  */
2213 	  tree fn = DECL_CONTEXT (decl);
2214 	  if (DECL_VISIBILITY_SPECIFIED (fn))
2215 	    {
2216 	      DECL_VISIBILITY (decl) = DECL_VISIBILITY (fn);
2217 	      DECL_VISIBILITY_SPECIFIED (decl) =
2218 		DECL_VISIBILITY_SPECIFIED (fn);
2219 	    }
2220 	  else
2221 	    {
2222 	      if (DECL_CLASS_SCOPE_P (fn))
2223 		determine_visibility_from_class (decl, DECL_CONTEXT (fn));
2224 	      else if (determine_hidden_inline (fn))
2225 		{
2226 		  DECL_VISIBILITY (decl) = default_visibility;
2227 		  DECL_VISIBILITY_SPECIFIED (decl) =
2228 		    visibility_options.inpragma;
2229 		}
2230 	      else
2231 		{
2232 	          DECL_VISIBILITY (decl) = DECL_VISIBILITY (fn);
2233 	          DECL_VISIBILITY_SPECIFIED (decl) =
2234 		    DECL_VISIBILITY_SPECIFIED (fn);
2235 		}
2236 	    }
2237 
2238 	  /* Local classes in templates have CLASSTYPE_USE_TEMPLATE set,
2239 	     but have no TEMPLATE_INFO, so don't try to check it.  */
2240 	  use_template = 0;
2241 	}
2242       else if (VAR_P (decl) && DECL_TINFO_P (decl)
2243 	       && flag_visibility_ms_compat)
2244 	{
2245 	  /* Under -fvisibility-ms-compat, types are visible by default,
2246 	     even though their contents aren't.  */
2247 	  tree underlying_type = TREE_TYPE (DECL_NAME (decl));
2248 	  int underlying_vis = type_visibility (underlying_type);
2249 	  if (underlying_vis == VISIBILITY_ANON
2250 	      || (CLASS_TYPE_P (underlying_type)
2251 		  && CLASSTYPE_VISIBILITY_SPECIFIED (underlying_type)))
2252 	    constrain_visibility (decl, underlying_vis, false);
2253 	  else
2254 	    DECL_VISIBILITY (decl) = VISIBILITY_DEFAULT;
2255 	}
2256       else if (VAR_P (decl) && DECL_TINFO_P (decl))
2257 	{
2258 	  /* tinfo visibility is based on the type it's for.  */
2259 	  constrain_visibility
2260 	    (decl, type_visibility (TREE_TYPE (DECL_NAME (decl))), false);
2261 
2262 	  /* Give the target a chance to override the visibility associated
2263 	     with DECL.  */
2264 	  if (TREE_PUBLIC (decl)
2265 	      && !DECL_REALLY_EXTERN (decl)
2266 	      && CLASS_TYPE_P (TREE_TYPE (DECL_NAME (decl)))
2267 	      && !CLASSTYPE_VISIBILITY_SPECIFIED (TREE_TYPE (DECL_NAME (decl))))
2268 	    targetm.cxx.determine_class_data_visibility (decl);
2269 	}
2270       else if (use_template)
2271 	/* Template instantiations and specializations get visibility based
2272 	   on their template unless they override it with an attribute.  */;
2273       else if (! DECL_VISIBILITY_SPECIFIED (decl))
2274 	{
2275           if (determine_hidden_inline (decl))
2276 	    DECL_VISIBILITY (decl) = VISIBILITY_HIDDEN;
2277 	  else
2278             {
2279 	      /* Set default visibility to whatever the user supplied with
2280 	         #pragma GCC visibility or a namespace visibility attribute.  */
2281 	      DECL_VISIBILITY (decl) = default_visibility;
2282 	      DECL_VISIBILITY_SPECIFIED (decl) = visibility_options.inpragma;
2283             }
2284 	}
2285     }
2286 
2287   if (use_template)
2288     {
2289       /* If the specialization doesn't specify visibility, use the
2290 	 visibility from the template.  */
2291       tree tinfo = (TREE_CODE (decl) == TYPE_DECL
2292 		    ? TYPE_TEMPLATE_INFO (TREE_TYPE (decl))
2293 		    : DECL_TEMPLATE_INFO (decl));
2294       tree args = TI_ARGS (tinfo);
2295       tree attribs = (TREE_CODE (decl) == TYPE_DECL
2296 		      ? TYPE_ATTRIBUTES (TREE_TYPE (decl))
2297 		      : DECL_ATTRIBUTES (decl));
2298 
2299       if (args != error_mark_node)
2300 	{
2301 	  tree pattern = DECL_TEMPLATE_RESULT (TI_TEMPLATE (tinfo));
2302 
2303 	  if (!DECL_VISIBILITY_SPECIFIED (decl))
2304 	    {
2305 	      if (!DECL_VISIBILITY_SPECIFIED (pattern)
2306 		  && determine_hidden_inline (decl))
2307 		DECL_VISIBILITY (decl) = VISIBILITY_HIDDEN;
2308 	      else
2309 		{
2310 	          DECL_VISIBILITY (decl) = DECL_VISIBILITY (pattern);
2311 	          DECL_VISIBILITY_SPECIFIED (decl)
2312 		    = DECL_VISIBILITY_SPECIFIED (pattern);
2313 		}
2314 	    }
2315 
2316 	  if (args
2317 	      /* Template argument visibility outweighs #pragma or namespace
2318 		 visibility, but not an explicit attribute.  */
2319 	      && !lookup_attribute ("visibility", attribs))
2320 	    {
2321 	      int depth = TMPL_ARGS_DEPTH (args);
2322 	      if (DECL_VISIBILITY_SPECIFIED (decl))
2323 		{
2324 		  /* A class template member with explicit visibility
2325 		     overrides the class visibility, so we need to apply
2326 		     all the levels of template args directly.  */
2327 		  int i;
2328 		  for (i = 1; i <= depth; ++i)
2329 		    {
2330 		      tree lev = TMPL_ARGS_LEVEL (args, i);
2331 		      constrain_visibility_for_template (decl, lev);
2332 		    }
2333 		}
2334 	      else if (PRIMARY_TEMPLATE_P (TI_TEMPLATE (tinfo)))
2335 		/* Limit visibility based on its template arguments.  */
2336 		constrain_visibility_for_template (decl, args);
2337 	    }
2338 	}
2339     }
2340 
2341   if (class_type)
2342     determine_visibility_from_class (decl, class_type);
2343 
2344   if (decl_anon_ns_mem_p (decl))
2345     /* Names in an anonymous namespace get internal linkage.
2346        This might change once we implement export.  */
2347     constrain_visibility (decl, VISIBILITY_ANON, false);
2348   else if (TREE_CODE (decl) != TYPE_DECL)
2349     {
2350       /* Propagate anonymity from type to decl.  */
2351       int tvis = type_visibility (TREE_TYPE (decl));
2352       if (tvis == VISIBILITY_ANON
2353 	  || ! DECL_VISIBILITY_SPECIFIED (decl))
2354 	constrain_visibility (decl, tvis, false);
2355     }
2356   else if (no_linkage_check (TREE_TYPE (decl), /*relaxed_p=*/true))
2357     /* DR 757: A type without linkage shall not be used as the type of a
2358        variable or function with linkage, unless
2359        o the variable or function has extern "C" linkage (7.5 [dcl.link]), or
2360        o the variable or function is not used (3.2 [basic.def.odr]) or is
2361        defined in the same translation unit.
2362 
2363        Since non-extern "C" decls need to be defined in the same
2364        translation unit, we can make the type internal.  */
2365     constrain_visibility (decl, VISIBILITY_ANON, false);
2366 
2367   /* If visibility changed and DECL already has DECL_RTL, ensure
2368      symbol flags are updated.  */
2369   if ((DECL_VISIBILITY (decl) != orig_visibility
2370        || DECL_VISIBILITY_SPECIFIED (decl) != orig_visibility_specified)
2371       && ((VAR_P (decl) && TREE_STATIC (decl))
2372 	  || TREE_CODE (decl) == FUNCTION_DECL)
2373       && DECL_RTL_SET_P (decl))
2374     make_decl_rtl (decl);
2375 }
2376 
2377 /* By default, static data members and function members receive
2378    the visibility of their containing class.  */
2379 
2380 static void
determine_visibility_from_class(tree decl,tree class_type)2381 determine_visibility_from_class (tree decl, tree class_type)
2382 {
2383   if (DECL_VISIBILITY_SPECIFIED (decl))
2384     return;
2385 
2386   if (determine_hidden_inline (decl))
2387     DECL_VISIBILITY (decl) = VISIBILITY_HIDDEN;
2388   else
2389     {
2390       /* Default to the class visibility.  */
2391       DECL_VISIBILITY (decl) = CLASSTYPE_VISIBILITY (class_type);
2392       DECL_VISIBILITY_SPECIFIED (decl)
2393 	= CLASSTYPE_VISIBILITY_SPECIFIED (class_type);
2394     }
2395 
2396   /* Give the target a chance to override the visibility associated
2397      with DECL.  */
2398   if (VAR_P (decl)
2399       && (DECL_TINFO_P (decl)
2400 	  || (DECL_VTABLE_OR_VTT_P (decl)
2401 	      /* Construction virtual tables are not exported because
2402 		 they cannot be referred to from other object files;
2403 		 their name is not standardized by the ABI.  */
2404 	      && !DECL_CONSTRUCTION_VTABLE_P (decl)))
2405       && TREE_PUBLIC (decl)
2406       && !DECL_REALLY_EXTERN (decl)
2407       && !CLASSTYPE_VISIBILITY_SPECIFIED (class_type))
2408     targetm.cxx.determine_class_data_visibility (decl);
2409 }
2410 
2411 /* Returns true iff DECL is an inline that should get hidden visibility
2412    because of -fvisibility-inlines-hidden.  */
2413 
2414 static bool
determine_hidden_inline(tree decl)2415 determine_hidden_inline (tree decl)
2416 {
2417   return (visibility_options.inlines_hidden
2418 	  /* Don't do this for inline templates; specializations might not be
2419 	     inline, and we don't want them to inherit the hidden
2420 	     visibility.  We'll set it here for all inline instantiations.  */
2421 	  && !processing_template_decl
2422 	  && TREE_CODE (decl) == FUNCTION_DECL
2423 	  && DECL_DECLARED_INLINE_P (decl)
2424 	  && (! DECL_LANG_SPECIFIC (decl)
2425 	      || ! DECL_EXPLICIT_INSTANTIATION (decl)));
2426 }
2427 
2428 /* Constrain the visibility of a class TYPE based on the visibility of its
2429    field types.  Warn if any fields require lesser visibility.  */
2430 
2431 void
constrain_class_visibility(tree type)2432 constrain_class_visibility (tree type)
2433 {
2434   tree binfo;
2435   tree t;
2436   int i;
2437 
2438   int vis = type_visibility (type);
2439 
2440   if (vis == VISIBILITY_ANON
2441       || DECL_IN_SYSTEM_HEADER (TYPE_MAIN_DECL (type)))
2442     return;
2443 
2444   /* Don't warn about visibility if the class has explicit visibility.  */
2445   if (CLASSTYPE_VISIBILITY_SPECIFIED (type))
2446     vis = VISIBILITY_INTERNAL;
2447 
2448   for (t = TYPE_FIELDS (type); t; t = DECL_CHAIN (t))
2449     if (TREE_CODE (t) == FIELD_DECL && TREE_TYPE (t) != error_mark_node)
2450       {
2451 	tree ftype = strip_pointer_or_array_types (TREE_TYPE (t));
2452 	int subvis = type_visibility (ftype);
2453 
2454 	if (subvis == VISIBILITY_ANON)
2455 	  {
2456 	    if (!in_main_input_context ())
2457 	      warning (0, "\
2458 %qT has a field %qD whose type uses the anonymous namespace",
2459 		       type, t);
2460 	  }
2461 	else if (MAYBE_CLASS_TYPE_P (ftype)
2462 		 && vis < VISIBILITY_HIDDEN
2463 		 && subvis >= VISIBILITY_HIDDEN)
2464 	  warning (OPT_Wattributes, "\
2465 %qT declared with greater visibility than the type of its field %qD",
2466 		   type, t);
2467       }
2468 
2469   binfo = TYPE_BINFO (type);
2470   for (i = 0; BINFO_BASE_ITERATE (binfo, i, t); ++i)
2471     {
2472       int subvis = type_visibility (TREE_TYPE (t));
2473 
2474       if (subvis == VISIBILITY_ANON)
2475         {
2476 	  if (!in_main_input_context())
2477 	    warning (0, "\
2478 %qT has a base %qT whose type uses the anonymous namespace",
2479 		     type, TREE_TYPE (t));
2480 	}
2481       else if (vis < VISIBILITY_HIDDEN
2482 	       && subvis >= VISIBILITY_HIDDEN)
2483 	warning (OPT_Wattributes, "\
2484 %qT declared with greater visibility than its base %qT",
2485 		 type, TREE_TYPE (t));
2486     }
2487 }
2488 
2489 /* Functions for adjusting the visibility of a tagged type and its nested
2490    types and declarations when it gets a name for linkage purposes from a
2491    typedef.  */
2492 
2493 static void bt_reset_linkage_1 (binding_entry, void *);
2494 static void bt_reset_linkage_2 (binding_entry, void *);
2495 
2496 /* First reset the visibility of all the types.  */
2497 
2498 static void
reset_type_linkage_1(tree type)2499 reset_type_linkage_1 (tree type)
2500 {
2501   set_linkage_according_to_type (type, TYPE_MAIN_DECL (type));
2502   if (CLASS_TYPE_P (type))
2503     binding_table_foreach (CLASSTYPE_NESTED_UTDS (type),
2504 			   bt_reset_linkage_1, NULL);
2505 }
2506 static void
bt_reset_linkage_1(binding_entry b,void *)2507 bt_reset_linkage_1 (binding_entry b, void */*data*/)
2508 {
2509   reset_type_linkage_1 (b->type);
2510 }
2511 
2512 /* Then reset the visibility of any static data members or member
2513    functions that use those types.  */
2514 
2515 static void
reset_decl_linkage(tree decl)2516 reset_decl_linkage (tree decl)
2517 {
2518   if (TREE_PUBLIC (decl))
2519     return;
2520   if (DECL_CLONED_FUNCTION_P (decl))
2521     return;
2522   TREE_PUBLIC (decl) = true;
2523   DECL_INTERFACE_KNOWN (decl) = false;
2524   determine_visibility (decl);
2525   tentative_decl_linkage (decl);
2526 }
2527 static void
reset_type_linkage_2(tree type)2528 reset_type_linkage_2 (tree type)
2529 {
2530   if (CLASS_TYPE_P (type))
2531     {
2532       if (tree vt = CLASSTYPE_VTABLES (type))
2533 	{
2534 	  tree name = mangle_vtbl_for_type (type);
2535 	  DECL_NAME (vt) = name;
2536 	  SET_DECL_ASSEMBLER_NAME (vt, name);
2537 	  reset_decl_linkage (vt);
2538 	}
2539       if (tree ti = CLASSTYPE_TYPEINFO_VAR (type))
2540 	{
2541 	  tree name = mangle_typeinfo_for_type (type);
2542 	  DECL_NAME (ti) = name;
2543 	  SET_DECL_ASSEMBLER_NAME (ti, name);
2544 	  TREE_TYPE (name) = type;
2545 	  reset_decl_linkage (ti);
2546 	}
2547       for (tree m = TYPE_FIELDS (type); m; m = DECL_CHAIN (m))
2548 	if (TREE_CODE (m) == VAR_DECL)
2549 	  reset_decl_linkage (m);
2550       for (tree m = TYPE_METHODS (type); m; m = DECL_CHAIN (m))
2551 	reset_decl_linkage (m);
2552       binding_table_foreach (CLASSTYPE_NESTED_UTDS (type),
2553 			     bt_reset_linkage_2, NULL);
2554     }
2555 }
2556 static void
bt_reset_linkage_2(binding_entry b,void *)2557 bt_reset_linkage_2 (binding_entry b, void */*data*/)
2558 {
2559   reset_type_linkage_2 (b->type);
2560 }
2561 void
reset_type_linkage(tree type)2562 reset_type_linkage (tree type)
2563 {
2564   reset_type_linkage_1 (type);
2565   reset_type_linkage_2 (type);
2566 }
2567 
2568 /* Set up our initial idea of what the linkage of DECL should be.  */
2569 
2570 void
tentative_decl_linkage(tree decl)2571 tentative_decl_linkage (tree decl)
2572 {
2573   if (DECL_INTERFACE_KNOWN (decl))
2574     /* We've already made a decision as to how this function will
2575        be handled.  */;
2576   else if (vague_linkage_p (decl))
2577     {
2578       if (TREE_CODE (decl) == FUNCTION_DECL
2579 	  && decl_defined_p (decl))
2580 	{
2581 	  DECL_EXTERNAL (decl) = 1;
2582 	  DECL_NOT_REALLY_EXTERN (decl) = 1;
2583 	  note_vague_linkage_fn (decl);
2584 	  /* A non-template inline function with external linkage will
2585 	     always be COMDAT.  As we must eventually determine the
2586 	     linkage of all functions, and as that causes writes to
2587 	     the data mapped in from the PCH file, it's advantageous
2588 	     to mark the functions at this point.  */
2589 	  if (DECL_DECLARED_INLINE_P (decl)
2590 	      && (!DECL_IMPLICIT_INSTANTIATION (decl)
2591 		  || DECL_DEFAULTED_FN (decl)))
2592 	    {
2593 	      /* This function must have external linkage, as
2594 		 otherwise DECL_INTERFACE_KNOWN would have been
2595 		 set.  */
2596 	      gcc_assert (TREE_PUBLIC (decl));
2597 	      comdat_linkage (decl);
2598 	      DECL_INTERFACE_KNOWN (decl) = 1;
2599 	    }
2600 	}
2601       else if (TREE_CODE (decl) == VAR_DECL)
2602 	maybe_commonize_var (decl);
2603     }
2604 }
2605 
2606 /* DECL is a FUNCTION_DECL or VAR_DECL.  If the object file linkage
2607    for DECL has not already been determined, do so now by setting
2608    DECL_EXTERNAL, DECL_COMDAT and other related flags.  Until this
2609    function is called entities with vague linkage whose definitions
2610    are available must have TREE_PUBLIC set.
2611 
2612    If this function decides to place DECL in COMDAT, it will set
2613    appropriate flags -- but will not clear DECL_EXTERNAL.  It is up to
2614    the caller to decide whether or not to clear DECL_EXTERNAL.  Some
2615    callers defer that decision until it is clear that DECL is actually
2616    required.  */
2617 
2618 void
import_export_decl(tree decl)2619 import_export_decl (tree decl)
2620 {
2621   int emit_p;
2622   bool comdat_p;
2623   bool import_p;
2624   tree class_type = NULL_TREE;
2625 
2626   if (DECL_INTERFACE_KNOWN (decl))
2627     return;
2628 
2629   /* We cannot determine what linkage to give to an entity with vague
2630      linkage until the end of the file.  For example, a virtual table
2631      for a class will be defined if and only if the key method is
2632      defined in this translation unit.  As a further example, consider
2633      that when compiling a translation unit that uses PCH file with
2634      "-frepo" it would be incorrect to make decisions about what
2635      entities to emit when building the PCH; those decisions must be
2636      delayed until the repository information has been processed.  */
2637   gcc_assert (at_eof);
2638   /* Object file linkage for explicit instantiations is handled in
2639      mark_decl_instantiated.  For static variables in functions with
2640      vague linkage, maybe_commonize_var is used.
2641 
2642      Therefore, the only declarations that should be provided to this
2643      function are those with external linkage that are:
2644 
2645      * implicit instantiations of function templates
2646 
2647      * inline function
2648 
2649      * implicit instantiations of static data members of class
2650        templates
2651 
2652      * virtual tables
2653 
2654      * typeinfo objects
2655 
2656      Furthermore, all entities that reach this point must have a
2657      definition available in this translation unit.
2658 
2659      The following assertions check these conditions.  */
2660   gcc_assert (VAR_OR_FUNCTION_DECL_P (decl));
2661   /* Any code that creates entities with TREE_PUBLIC cleared should
2662      also set DECL_INTERFACE_KNOWN.  */
2663   gcc_assert (TREE_PUBLIC (decl));
2664   if (TREE_CODE (decl) == FUNCTION_DECL)
2665     gcc_assert (DECL_IMPLICIT_INSTANTIATION (decl)
2666 		|| DECL_FRIEND_PSEUDO_TEMPLATE_INSTANTIATION (decl)
2667 		|| DECL_DECLARED_INLINE_P (decl));
2668   else
2669     gcc_assert (DECL_IMPLICIT_INSTANTIATION (decl)
2670 		|| DECL_VTABLE_OR_VTT_P (decl)
2671 		|| DECL_TINFO_P (decl));
2672   /* Check that a definition of DECL is available in this translation
2673      unit.  */
2674   gcc_assert (!DECL_REALLY_EXTERN (decl));
2675 
2676   /* Assume that DECL will not have COMDAT linkage.  */
2677   comdat_p = false;
2678   /* Assume that DECL will not be imported into this translation
2679      unit.  */
2680   import_p = false;
2681 
2682   /* See if the repository tells us whether or not to emit DECL in
2683      this translation unit.  */
2684   emit_p = repo_emit_p (decl);
2685   if (emit_p == 0)
2686     import_p = true;
2687   else if (emit_p == 1)
2688     {
2689       /* The repository indicates that this entity should be defined
2690 	 here.  Make sure the back end honors that request.  */
2691       mark_needed (decl);
2692       /* Output the definition as an ordinary strong definition.  */
2693       DECL_EXTERNAL (decl) = 0;
2694       DECL_INTERFACE_KNOWN (decl) = 1;
2695       return;
2696     }
2697 
2698   if (import_p)
2699     /* We have already decided what to do with this DECL; there is no
2700        need to check anything further.  */
2701     ;
2702   else if (VAR_P (decl) && DECL_VTABLE_OR_VTT_P (decl))
2703     {
2704       class_type = DECL_CONTEXT (decl);
2705       import_export_class (class_type);
2706       if (TYPE_FOR_JAVA (class_type))
2707 	import_p = true;
2708       else if (CLASSTYPE_INTERFACE_KNOWN (class_type)
2709 	       && CLASSTYPE_INTERFACE_ONLY (class_type))
2710 	import_p = true;
2711       else if ((!flag_weak || TARGET_WEAK_NOT_IN_ARCHIVE_TOC)
2712 	       && !CLASSTYPE_USE_TEMPLATE (class_type)
2713 	       && CLASSTYPE_KEY_METHOD (class_type)
2714 	       && !DECL_DECLARED_INLINE_P (CLASSTYPE_KEY_METHOD (class_type)))
2715 	/* The ABI requires that all virtual tables be emitted with
2716 	   COMDAT linkage.  However, on systems where COMDAT symbols
2717 	   don't show up in the table of contents for a static
2718 	   archive, or on systems without weak symbols (where we
2719 	   approximate COMDAT linkage by using internal linkage), the
2720 	   linker will report errors about undefined symbols because
2721 	   it will not see the virtual table definition.  Therefore,
2722 	   in the case that we know that the virtual table will be
2723 	   emitted in only one translation unit, we make the virtual
2724 	   table an ordinary definition with external linkage.  */
2725 	DECL_EXTERNAL (decl) = 0;
2726       else if (CLASSTYPE_INTERFACE_KNOWN (class_type))
2727 	{
2728 	  /* CLASS_TYPE is being exported from this translation unit,
2729 	     so DECL should be defined here.  */
2730 	  if (!flag_weak && CLASSTYPE_EXPLICIT_INSTANTIATION (class_type))
2731 	    /* If a class is declared in a header with the "extern
2732 	       template" extension, then it will not be instantiated,
2733 	       even in translation units that would normally require
2734 	       it.  Often such classes are explicitly instantiated in
2735 	       one translation unit.  Therefore, the explicit
2736 	       instantiation must be made visible to other translation
2737 	       units.  */
2738 	    DECL_EXTERNAL (decl) = 0;
2739 	  else
2740 	    {
2741 	      /* The generic C++ ABI says that class data is always
2742 		 COMDAT, even if there is a key function.  Some
2743 		 variants (e.g., the ARM EABI) says that class data
2744 		 only has COMDAT linkage if the class data might be
2745 		 emitted in more than one translation unit.  When the
2746 		 key method can be inline and is inline, we still have
2747 		 to arrange for comdat even though
2748 		 class_data_always_comdat is false.  */
2749 	      if (!CLASSTYPE_KEY_METHOD (class_type)
2750 		  || DECL_DECLARED_INLINE_P (CLASSTYPE_KEY_METHOD (class_type))
2751 		  || targetm.cxx.class_data_always_comdat ())
2752 		{
2753 		  /* The ABI requires COMDAT linkage.  Normally, we
2754 		     only emit COMDAT things when they are needed;
2755 		     make sure that we realize that this entity is
2756 		     indeed needed.  */
2757 		  comdat_p = true;
2758 		  mark_needed (decl);
2759 		}
2760 	    }
2761 	}
2762       else if (!flag_implicit_templates
2763 	       && CLASSTYPE_IMPLICIT_INSTANTIATION (class_type))
2764 	import_p = true;
2765       else
2766 	comdat_p = true;
2767     }
2768   else if (VAR_P (decl) && DECL_TINFO_P (decl))
2769     {
2770       tree type = TREE_TYPE (DECL_NAME (decl));
2771       if (CLASS_TYPE_P (type))
2772 	{
2773 	  class_type = type;
2774 	  import_export_class (type);
2775 	  if (CLASSTYPE_INTERFACE_KNOWN (type)
2776 	      && TYPE_POLYMORPHIC_P (type)
2777 	      && CLASSTYPE_INTERFACE_ONLY (type)
2778 	      /* If -fno-rtti was specified, then we cannot be sure
2779 		 that RTTI information will be emitted with the
2780 		 virtual table of the class, so we must emit it
2781 		 wherever it is used.  */
2782 	      && flag_rtti)
2783 	    import_p = true;
2784 	  else
2785 	    {
2786 	      if (CLASSTYPE_INTERFACE_KNOWN (type)
2787 		  && !CLASSTYPE_INTERFACE_ONLY (type))
2788 		{
2789 		  comdat_p = (targetm.cxx.class_data_always_comdat ()
2790 			      || (CLASSTYPE_KEY_METHOD (type)
2791 				  && DECL_DECLARED_INLINE_P (CLASSTYPE_KEY_METHOD (type))));
2792 		  mark_needed (decl);
2793 		  if (!flag_weak)
2794 		    {
2795 		      comdat_p = false;
2796 		      DECL_EXTERNAL (decl) = 0;
2797 		    }
2798 		}
2799 	      else
2800 		comdat_p = true;
2801 	    }
2802 	}
2803       else
2804 	comdat_p = true;
2805     }
2806   else if (DECL_TEMPLOID_INSTANTIATION (decl))
2807     {
2808       /* DECL is an implicit instantiation of a function or static
2809 	 data member.  */
2810       if ((flag_implicit_templates
2811 	   && !flag_use_repository)
2812 	  || (flag_implicit_inline_templates
2813 	      && TREE_CODE (decl) == FUNCTION_DECL
2814 	      && DECL_DECLARED_INLINE_P (decl)))
2815 	comdat_p = true;
2816       else
2817 	/* If we are not implicitly generating templates, then mark
2818 	   this entity as undefined in this translation unit.  */
2819 	import_p = true;
2820     }
2821   else if (DECL_FUNCTION_MEMBER_P (decl))
2822     {
2823       if (!DECL_DECLARED_INLINE_P (decl))
2824 	{
2825 	  tree ctype = DECL_CONTEXT (decl);
2826 	  import_export_class (ctype);
2827 	  if (CLASSTYPE_INTERFACE_KNOWN (ctype))
2828 	    {
2829 	      DECL_NOT_REALLY_EXTERN (decl)
2830 		= ! (CLASSTYPE_INTERFACE_ONLY (ctype)
2831 		     || (DECL_DECLARED_INLINE_P (decl)
2832 			 && ! flag_implement_inlines
2833 			 && !DECL_VINDEX (decl)));
2834 
2835 	      if (!DECL_NOT_REALLY_EXTERN (decl))
2836 		DECL_EXTERNAL (decl) = 1;
2837 
2838 	      /* Always make artificials weak.  */
2839 	      if (DECL_ARTIFICIAL (decl) && flag_weak)
2840 		comdat_p = true;
2841 	      else
2842 		maybe_make_one_only (decl);
2843 	    }
2844 	}
2845       else
2846 	comdat_p = true;
2847     }
2848   else
2849     comdat_p = true;
2850 
2851   if (import_p)
2852     {
2853       /* If we are importing DECL into this translation unit, mark is
2854 	 an undefined here.  */
2855       DECL_EXTERNAL (decl) = 1;
2856       DECL_NOT_REALLY_EXTERN (decl) = 0;
2857     }
2858   else if (comdat_p)
2859     {
2860       /* If we decided to put DECL in COMDAT, mark it accordingly at
2861 	 this point.  */
2862       comdat_linkage (decl);
2863     }
2864 
2865   DECL_INTERFACE_KNOWN (decl) = 1;
2866 }
2867 
2868 /* Return an expression that performs the destruction of DECL, which
2869    must be a VAR_DECL whose type has a non-trivial destructor, or is
2870    an array whose (innermost) elements have a non-trivial destructor.  */
2871 
2872 tree
build_cleanup(tree decl)2873 build_cleanup (tree decl)
2874 {
2875   tree clean = cxx_maybe_build_cleanup (decl, tf_warning_or_error);
2876   gcc_assert (clean != NULL_TREE);
2877   return clean;
2878 }
2879 
2880 /* Returns the initialization guard variable for the variable DECL,
2881    which has static storage duration.  */
2882 
2883 tree
get_guard(tree decl)2884 get_guard (tree decl)
2885 {
2886   tree sname;
2887   tree guard;
2888 
2889   sname = mangle_guard_variable (decl);
2890   guard = IDENTIFIER_GLOBAL_VALUE (sname);
2891   if (! guard)
2892     {
2893       tree guard_type;
2894 
2895       /* We use a type that is big enough to contain a mutex as well
2896 	 as an integer counter.  */
2897       guard_type = targetm.cxx.guard_type ();
2898       guard = build_decl (DECL_SOURCE_LOCATION (decl),
2899 			  VAR_DECL, sname, guard_type);
2900 
2901       /* The guard should have the same linkage as what it guards.  */
2902       TREE_PUBLIC (guard) = TREE_PUBLIC (decl);
2903       TREE_STATIC (guard) = TREE_STATIC (decl);
2904       DECL_COMMON (guard) = DECL_COMMON (decl);
2905       DECL_COMDAT (guard) = DECL_COMDAT (decl);
2906       DECL_TLS_MODEL (guard) = DECL_TLS_MODEL (decl);
2907       if (DECL_ONE_ONLY (decl))
2908 	make_decl_one_only (guard, cxx_comdat_group (guard));
2909       if (TREE_PUBLIC (decl))
2910 	DECL_WEAK (guard) = DECL_WEAK (decl);
2911       DECL_VISIBILITY (guard) = DECL_VISIBILITY (decl);
2912       DECL_VISIBILITY_SPECIFIED (guard) = DECL_VISIBILITY_SPECIFIED (decl);
2913 
2914       DECL_ARTIFICIAL (guard) = 1;
2915       DECL_IGNORED_P (guard) = 1;
2916       TREE_USED (guard) = 1;
2917       pushdecl_top_level_and_finish (guard, NULL_TREE);
2918     }
2919   return guard;
2920 }
2921 
2922 /* Return those bits of the GUARD variable that should be set when the
2923    guarded entity is actually initialized.  */
2924 
2925 static tree
get_guard_bits(tree guard)2926 get_guard_bits (tree guard)
2927 {
2928   if (!targetm.cxx.guard_mask_bit ())
2929     {
2930       /* We only set the first byte of the guard, in order to leave room
2931 	 for a mutex in the high-order bits.  */
2932       guard = build1 (ADDR_EXPR,
2933 		      build_pointer_type (TREE_TYPE (guard)),
2934 		      guard);
2935       guard = build1 (NOP_EXPR,
2936 		      build_pointer_type (char_type_node),
2937 		      guard);
2938       guard = build1 (INDIRECT_REF, char_type_node, guard);
2939     }
2940 
2941   return guard;
2942 }
2943 
2944 /* Return an expression which determines whether or not the GUARD
2945    variable has already been initialized.  */
2946 
2947 tree
get_guard_cond(tree guard)2948 get_guard_cond (tree guard)
2949 {
2950   tree guard_value;
2951 
2952   /* Check to see if the GUARD is zero.  */
2953   guard = get_guard_bits (guard);
2954 
2955   /* Mask off all but the low bit.  */
2956   if (targetm.cxx.guard_mask_bit ())
2957     {
2958       guard_value = integer_one_node;
2959       if (!same_type_p (TREE_TYPE (guard_value), TREE_TYPE (guard)))
2960 	guard_value = convert (TREE_TYPE (guard), guard_value);
2961       guard = cp_build_binary_op (input_location,
2962 				  BIT_AND_EXPR, guard, guard_value,
2963 				  tf_warning_or_error);
2964     }
2965 
2966   guard_value = integer_zero_node;
2967   if (!same_type_p (TREE_TYPE (guard_value), TREE_TYPE (guard)))
2968     guard_value = convert (TREE_TYPE (guard), guard_value);
2969   return cp_build_binary_op (input_location,
2970 			     EQ_EXPR, guard, guard_value,
2971 			     tf_warning_or_error);
2972 }
2973 
2974 /* Return an expression which sets the GUARD variable, indicating that
2975    the variable being guarded has been initialized.  */
2976 
2977 tree
set_guard(tree guard)2978 set_guard (tree guard)
2979 {
2980   tree guard_init;
2981 
2982   /* Set the GUARD to one.  */
2983   guard = get_guard_bits (guard);
2984   guard_init = integer_one_node;
2985   if (!same_type_p (TREE_TYPE (guard_init), TREE_TYPE (guard)))
2986     guard_init = convert (TREE_TYPE (guard), guard_init);
2987   return cp_build_modify_expr (guard, NOP_EXPR, guard_init,
2988 			       tf_warning_or_error);
2989 }
2990 
2991 /* Returns true iff we can tell that VAR does not have a dynamic
2992    initializer.  */
2993 
2994 static bool
var_defined_without_dynamic_init(tree var)2995 var_defined_without_dynamic_init (tree var)
2996 {
2997   /* If it's defined in another TU, we can't tell.  */
2998   if (DECL_EXTERNAL (var))
2999     return false;
3000   /* If it has a non-trivial destructor, registering the destructor
3001      counts as dynamic initialization.  */
3002   if (TYPE_HAS_NONTRIVIAL_DESTRUCTOR (TREE_TYPE (var)))
3003     return false;
3004   /* If it's in this TU, its initializer has been processed.  */
3005   gcc_assert (DECL_INITIALIZED_P (var));
3006   /* If it has no initializer or a constant one, it's not dynamic.  */
3007   return (!DECL_NONTRIVIALLY_INITIALIZED_P (var)
3008 	  || DECL_INITIALIZED_BY_CONSTANT_EXPRESSION_P (var));
3009 }
3010 
3011 /* Returns true iff VAR is a variable that needs uses to be
3012    wrapped for possible dynamic initialization.  */
3013 
3014 static bool
var_needs_tls_wrapper(tree var)3015 var_needs_tls_wrapper (tree var)
3016 {
3017   return (!error_operand_p (var)
3018 	  && DECL_THREAD_LOCAL_P (var)
3019 	  && !DECL_GNU_TLS_P (var)
3020 	  && !DECL_FUNCTION_SCOPE_P (var)
3021 	  && !var_defined_without_dynamic_init (var));
3022 }
3023 
3024 /* Get the FUNCTION_DECL for the shared TLS init function for this
3025    translation unit.  */
3026 
3027 static tree
get_local_tls_init_fn(void)3028 get_local_tls_init_fn (void)
3029 {
3030   tree sname = get_identifier ("__tls_init");
3031   tree fn = IDENTIFIER_GLOBAL_VALUE (sname);
3032   if (!fn)
3033     {
3034       fn = build_lang_decl (FUNCTION_DECL, sname,
3035 			     build_function_type (void_type_node,
3036 						  void_list_node));
3037       SET_DECL_LANGUAGE (fn, lang_c);
3038       TREE_PUBLIC (fn) = false;
3039       DECL_ARTIFICIAL (fn) = true;
3040       mark_used (fn);
3041       SET_IDENTIFIER_GLOBAL_VALUE (sname, fn);
3042     }
3043   return fn;
3044 }
3045 
3046 /* Get a FUNCTION_DECL for the init function for the thread_local
3047    variable VAR.  The init function will be an alias to the function
3048    that initializes all the non-local TLS variables in the translation
3049    unit.  The init function is only used by the wrapper function.  */
3050 
3051 static tree
get_tls_init_fn(tree var)3052 get_tls_init_fn (tree var)
3053 {
3054   /* Only C++11 TLS vars need this init fn.  */
3055   if (!var_needs_tls_wrapper (var))
3056     return NULL_TREE;
3057 
3058   /* If -fno-extern-tls-init, assume that we don't need to call
3059      a tls init function for a variable defined in another TU.  */
3060   if (!flag_extern_tls_init && DECL_EXTERNAL (var))
3061     return NULL_TREE;
3062 
3063 #ifdef ASM_OUTPUT_DEF
3064   /* If the variable is internal, or if we can't generate aliases,
3065      call the local init function directly.  */
3066   if (!TREE_PUBLIC (var))
3067 #endif
3068     return get_local_tls_init_fn ();
3069 
3070   tree sname = mangle_tls_init_fn (var);
3071   tree fn = IDENTIFIER_GLOBAL_VALUE (sname);
3072   if (!fn)
3073     {
3074       fn = build_lang_decl (FUNCTION_DECL, sname,
3075 			    build_function_type (void_type_node,
3076 						 void_list_node));
3077       SET_DECL_LANGUAGE (fn, lang_c);
3078       TREE_PUBLIC (fn) = TREE_PUBLIC (var);
3079       DECL_ARTIFICIAL (fn) = true;
3080       DECL_COMDAT (fn) = DECL_COMDAT (var);
3081       DECL_EXTERNAL (fn) = DECL_EXTERNAL (var);
3082       if (DECL_ONE_ONLY (var))
3083 	make_decl_one_only (fn, cxx_comdat_group (fn));
3084       if (TREE_PUBLIC (var))
3085 	{
3086 	  tree obtype = strip_array_types (non_reference (TREE_TYPE (var)));
3087 	  /* If the variable is defined somewhere else and might have static
3088 	     initialization, make the init function a weak reference.  */
3089 	  if ((!TYPE_NEEDS_CONSTRUCTING (obtype)
3090 	       || TYPE_HAS_CONSTEXPR_CTOR (obtype))
3091 	      && TYPE_HAS_TRIVIAL_DESTRUCTOR (obtype)
3092 	      && DECL_EXTERNAL (var))
3093 	    declare_weak (fn);
3094 	  else
3095 	    DECL_WEAK (fn) = DECL_WEAK (var);
3096 	}
3097       DECL_VISIBILITY (fn) = DECL_VISIBILITY (var);
3098       DECL_VISIBILITY_SPECIFIED (fn) = DECL_VISIBILITY_SPECIFIED (var);
3099       DECL_DLLIMPORT_P (fn) = DECL_DLLIMPORT_P (var);
3100       DECL_IGNORED_P (fn) = 1;
3101       mark_used (fn);
3102 
3103       DECL_BEFRIENDING_CLASSES (fn) = var;
3104 
3105       SET_IDENTIFIER_GLOBAL_VALUE (sname, fn);
3106     }
3107   return fn;
3108 }
3109 
3110 /* Get a FUNCTION_DECL for the init wrapper function for the thread_local
3111    variable VAR.  The wrapper function calls the init function (if any) for
3112    VAR and then returns a reference to VAR.  The wrapper function is used
3113    in place of VAR everywhere VAR is mentioned.  */
3114 
3115 tree
get_tls_wrapper_fn(tree var)3116 get_tls_wrapper_fn (tree var)
3117 {
3118   /* Only C++11 TLS vars need this wrapper fn.  */
3119   if (!var_needs_tls_wrapper (var))
3120     return NULL_TREE;
3121 
3122   tree sname = mangle_tls_wrapper_fn (var);
3123   tree fn = IDENTIFIER_GLOBAL_VALUE (sname);
3124   if (!fn)
3125     {
3126       /* A named rvalue reference is an lvalue, so the wrapper should
3127 	 always return an lvalue reference.  */
3128       tree type = non_reference (TREE_TYPE (var));
3129       type = build_reference_type (type);
3130       tree fntype = build_function_type (type, void_list_node);
3131       fn = build_lang_decl (FUNCTION_DECL, sname, fntype);
3132       SET_DECL_LANGUAGE (fn, lang_c);
3133       TREE_PUBLIC (fn) = TREE_PUBLIC (var);
3134       DECL_ARTIFICIAL (fn) = true;
3135       DECL_IGNORED_P (fn) = 1;
3136       /* The wrapper is inline and emitted everywhere var is used.  */
3137       DECL_DECLARED_INLINE_P (fn) = true;
3138       if (TREE_PUBLIC (var))
3139 	{
3140 	  comdat_linkage (fn);
3141 #ifdef HAVE_GAS_HIDDEN
3142 	  /* Make the wrapper bind locally; there's no reason to share
3143 	     the wrapper between multiple shared objects.  */
3144 	  DECL_VISIBILITY (fn) = VISIBILITY_INTERNAL;
3145 	  DECL_VISIBILITY_SPECIFIED (fn) = true;
3146 #endif
3147 	}
3148       if (!TREE_PUBLIC (fn))
3149 	DECL_INTERFACE_KNOWN (fn) = true;
3150       mark_used (fn);
3151       note_vague_linkage_fn (fn);
3152 
3153 #if 0
3154       /* We want CSE to commonize calls to the wrapper, but marking it as
3155 	 pure is unsafe since it has side-effects.  I guess we need a new
3156 	 ECF flag even weaker than ECF_PURE.  FIXME!  */
3157       DECL_PURE_P (fn) = true;
3158 #endif
3159 
3160       DECL_BEFRIENDING_CLASSES (fn) = var;
3161 
3162       SET_IDENTIFIER_GLOBAL_VALUE (sname, fn);
3163     }
3164   return fn;
3165 }
3166 
3167 /* At EOF, generate the definition for the TLS wrapper function FN:
3168 
3169    T& var_wrapper() {
3170      if (init_fn) init_fn();
3171      return var;
3172    }  */
3173 
3174 static void
generate_tls_wrapper(tree fn)3175 generate_tls_wrapper (tree fn)
3176 {
3177   tree var = DECL_BEFRIENDING_CLASSES (fn);
3178 
3179   start_preparsed_function (fn, NULL_TREE, SF_DEFAULT | SF_PRE_PARSED);
3180   tree body = begin_function_body ();
3181   /* Only call the init fn if there might be one.  */
3182   if (tree init_fn = get_tls_init_fn (var))
3183     {
3184       tree if_stmt = NULL_TREE;
3185       /* If init_fn is a weakref, make sure it exists before calling.  */
3186       if (lookup_attribute ("weak", DECL_ATTRIBUTES (init_fn)))
3187 	{
3188 	  if_stmt = begin_if_stmt ();
3189 	  tree addr = cp_build_addr_expr (init_fn, tf_warning_or_error);
3190 	  tree cond = cp_build_binary_op (DECL_SOURCE_LOCATION (var),
3191 					  NE_EXPR, addr, nullptr_node,
3192 					  tf_warning_or_error);
3193 	  finish_if_stmt_cond (cond, if_stmt);
3194 	}
3195       finish_expr_stmt (build_cxx_call
3196 			(init_fn, 0, NULL, tf_warning_or_error));
3197       if (if_stmt)
3198 	{
3199 	  finish_then_clause (if_stmt);
3200 	  finish_if_stmt (if_stmt);
3201 	}
3202     }
3203   else
3204     /* If there's no initialization, the wrapper is a constant function.  */
3205     TREE_READONLY (fn) = true;
3206   finish_return_stmt (convert_from_reference (var));
3207   finish_function_body (body);
3208   expand_or_defer_fn (finish_function (0));
3209 }
3210 
3211 /* Start the process of running a particular set of global constructors
3212    or destructors.  Subroutine of do_[cd]tors.  Also called from
3213    vtv_start_verification_constructor_init_function.  */
3214 
3215 static tree
start_objects(int method_type,int initp)3216 start_objects (int method_type, int initp)
3217 {
3218   tree body;
3219   tree fndecl;
3220   char type[14];
3221 
3222   /* Make ctor or dtor function.  METHOD_TYPE may be 'I' or 'D'.  */
3223 
3224   if (initp != DEFAULT_INIT_PRIORITY)
3225     {
3226       char joiner;
3227 
3228 #ifdef JOINER
3229       joiner = JOINER;
3230 #else
3231       joiner = '_';
3232 #endif
3233 
3234       sprintf (type, "sub_%c%c%.5u", method_type, joiner, initp);
3235     }
3236   else
3237     sprintf (type, "sub_%c", method_type);
3238 
3239   fndecl = build_lang_decl (FUNCTION_DECL,
3240 			    get_file_function_name (type),
3241 			    build_function_type_list (void_type_node,
3242 						      NULL_TREE));
3243   start_preparsed_function (fndecl, /*attrs=*/NULL_TREE, SF_PRE_PARSED);
3244 
3245   TREE_PUBLIC (current_function_decl) = 0;
3246 
3247   /* Mark as artificial because it's not explicitly in the user's
3248      source code.  */
3249   DECL_ARTIFICIAL (current_function_decl) = 1;
3250 
3251   /* Mark this declaration as used to avoid spurious warnings.  */
3252   TREE_USED (current_function_decl) = 1;
3253 
3254   /* Mark this function as a global constructor or destructor.  */
3255   if (method_type == 'I')
3256     DECL_GLOBAL_CTOR_P (current_function_decl) = 1;
3257   else
3258     DECL_GLOBAL_DTOR_P (current_function_decl) = 1;
3259 
3260   body = begin_compound_stmt (BCS_FN_BODY);
3261 
3262   return body;
3263 }
3264 
3265 /* Finish the process of running a particular set of global constructors
3266    or destructors.  Subroutine of do_[cd]tors.  */
3267 
3268 static void
finish_objects(int method_type,int initp,tree body)3269 finish_objects (int method_type, int initp, tree body)
3270 {
3271   tree fn;
3272 
3273   /* Finish up.  */
3274   finish_compound_stmt (body);
3275   fn = finish_function (0);
3276 
3277   if (method_type == 'I')
3278     {
3279       DECL_STATIC_CONSTRUCTOR (fn) = 1;
3280       decl_init_priority_insert (fn, initp);
3281     }
3282   else
3283     {
3284       DECL_STATIC_DESTRUCTOR (fn) = 1;
3285       decl_fini_priority_insert (fn, initp);
3286     }
3287 
3288   expand_or_defer_fn (fn);
3289 }
3290 
3291 /* The names of the parameters to the function created to handle
3292    initializations and destructions for objects with static storage
3293    duration.  */
3294 #define INITIALIZE_P_IDENTIFIER "__initialize_p"
3295 #define PRIORITY_IDENTIFIER "__priority"
3296 
3297 /* The name of the function we create to handle initializations and
3298    destructions for objects with static storage duration.  */
3299 #define SSDF_IDENTIFIER "__static_initialization_and_destruction"
3300 
3301 /* The declaration for the __INITIALIZE_P argument.  */
3302 static GTY(()) tree initialize_p_decl;
3303 
3304 /* The declaration for the __PRIORITY argument.  */
3305 static GTY(()) tree priority_decl;
3306 
3307 /* The declaration for the static storage duration function.  */
3308 static GTY(()) tree ssdf_decl;
3309 
3310 /* All the static storage duration functions created in this
3311    translation unit.  */
3312 static GTY(()) vec<tree, va_gc> *ssdf_decls;
3313 
3314 /* A map from priority levels to information about that priority
3315    level.  There may be many such levels, so efficient lookup is
3316    important.  */
3317 static splay_tree priority_info_map;
3318 
3319 /* Begins the generation of the function that will handle all
3320    initialization and destruction of objects with static storage
3321    duration.  The function generated takes two parameters of type
3322    `int': __INITIALIZE_P and __PRIORITY.  If __INITIALIZE_P is
3323    nonzero, it performs initializations.  Otherwise, it performs
3324    destructions.  It only performs those initializations or
3325    destructions with the indicated __PRIORITY.  The generated function
3326    returns no value.
3327 
3328    It is assumed that this function will only be called once per
3329    translation unit.  */
3330 
3331 static tree
start_static_storage_duration_function(unsigned count)3332 start_static_storage_duration_function (unsigned count)
3333 {
3334   tree type;
3335   tree body;
3336   char id[sizeof (SSDF_IDENTIFIER) + 1 /* '\0' */ + 32];
3337 
3338   /* Create the identifier for this function.  It will be of the form
3339      SSDF_IDENTIFIER_<number>.  */
3340   sprintf (id, "%s_%u", SSDF_IDENTIFIER, count);
3341 
3342   type = build_function_type_list (void_type_node,
3343 				   integer_type_node, integer_type_node,
3344 				   NULL_TREE);
3345 
3346   /* Create the FUNCTION_DECL itself.  */
3347   ssdf_decl = build_lang_decl (FUNCTION_DECL,
3348 			       get_identifier (id),
3349 			       type);
3350   TREE_PUBLIC (ssdf_decl) = 0;
3351   DECL_ARTIFICIAL (ssdf_decl) = 1;
3352 
3353   /* Put this function in the list of functions to be called from the
3354      static constructors and destructors.  */
3355   if (!ssdf_decls)
3356     {
3357       vec_alloc (ssdf_decls, 32);
3358 
3359       /* Take this opportunity to initialize the map from priority
3360 	 numbers to information about that priority level.  */
3361       priority_info_map = splay_tree_new (splay_tree_compare_ints,
3362 					  /*delete_key_fn=*/0,
3363 					  /*delete_value_fn=*/
3364 					  (splay_tree_delete_value_fn) &free);
3365 
3366       /* We always need to generate functions for the
3367 	 DEFAULT_INIT_PRIORITY so enter it now.  That way when we walk
3368 	 priorities later, we'll be sure to find the
3369 	 DEFAULT_INIT_PRIORITY.  */
3370       get_priority_info (DEFAULT_INIT_PRIORITY);
3371     }
3372 
3373   vec_safe_push (ssdf_decls, ssdf_decl);
3374 
3375   /* Create the argument list.  */
3376   initialize_p_decl = cp_build_parm_decl
3377     (get_identifier (INITIALIZE_P_IDENTIFIER), integer_type_node);
3378   DECL_CONTEXT (initialize_p_decl) = ssdf_decl;
3379   TREE_USED (initialize_p_decl) = 1;
3380   priority_decl = cp_build_parm_decl
3381     (get_identifier (PRIORITY_IDENTIFIER), integer_type_node);
3382   DECL_CONTEXT (priority_decl) = ssdf_decl;
3383   TREE_USED (priority_decl) = 1;
3384 
3385   DECL_CHAIN (initialize_p_decl) = priority_decl;
3386   DECL_ARGUMENTS (ssdf_decl) = initialize_p_decl;
3387 
3388   /* Put the function in the global scope.  */
3389   pushdecl (ssdf_decl);
3390 
3391   /* Start the function itself.  This is equivalent to declaring the
3392      function as:
3393 
3394        static void __ssdf (int __initialize_p, init __priority_p);
3395 
3396      It is static because we only need to call this function from the
3397      various constructor and destructor functions for this module.  */
3398   start_preparsed_function (ssdf_decl,
3399 			    /*attrs=*/NULL_TREE,
3400 			    SF_PRE_PARSED);
3401 
3402   /* Set up the scope of the outermost block in the function.  */
3403   body = begin_compound_stmt (BCS_FN_BODY);
3404 
3405   return body;
3406 }
3407 
3408 /* Finish the generation of the function which performs initialization
3409    and destruction of objects with static storage duration.  After
3410    this point, no more such objects can be created.  */
3411 
3412 static void
finish_static_storage_duration_function(tree body)3413 finish_static_storage_duration_function (tree body)
3414 {
3415   /* Close out the function.  */
3416   finish_compound_stmt (body);
3417   expand_or_defer_fn (finish_function (0));
3418 }
3419 
3420 /* Return the information about the indicated PRIORITY level.  If no
3421    code to handle this level has yet been generated, generate the
3422    appropriate prologue.  */
3423 
3424 static priority_info
get_priority_info(int priority)3425 get_priority_info (int priority)
3426 {
3427   priority_info pi;
3428   splay_tree_node n;
3429 
3430   n = splay_tree_lookup (priority_info_map,
3431 			 (splay_tree_key) priority);
3432   if (!n)
3433     {
3434       /* Create a new priority information structure, and insert it
3435 	 into the map.  */
3436       pi = XNEW (struct priority_info_s);
3437       pi->initializations_p = 0;
3438       pi->destructions_p = 0;
3439       splay_tree_insert (priority_info_map,
3440 			 (splay_tree_key) priority,
3441 			 (splay_tree_value) pi);
3442     }
3443   else
3444     pi = (priority_info) n->value;
3445 
3446   return pi;
3447 }
3448 
3449 /* The effective initialization priority of a DECL.  */
3450 
3451 #define DECL_EFFECTIVE_INIT_PRIORITY(decl)				      \
3452 	((!DECL_HAS_INIT_PRIORITY_P (decl) || DECL_INIT_PRIORITY (decl) == 0) \
3453 	 ? DEFAULT_INIT_PRIORITY : DECL_INIT_PRIORITY (decl))
3454 
3455 /* Whether a DECL needs a guard to protect it against multiple
3456    initialization.  */
3457 
3458 #define NEEDS_GUARD_P(decl) (TREE_PUBLIC (decl) && (DECL_COMMON (decl)      \
3459 						    || DECL_ONE_ONLY (decl) \
3460 						    || DECL_WEAK (decl)))
3461 
3462 /* Called from one_static_initialization_or_destruction(),
3463    via walk_tree.
3464    Walks the initializer list of a global variable and looks for
3465    temporary variables (DECL_NAME() == NULL and DECL_ARTIFICIAL != 0)
3466    and that have their DECL_CONTEXT() == NULL.
3467    For each such temporary variable, set their DECL_CONTEXT() to
3468    the current function. This is necessary because otherwise
3469    some optimizers (enabled by -O2 -fprofile-arcs) might crash
3470    when trying to refer to a temporary variable that does not have
3471    it's DECL_CONTECT() properly set.  */
3472 static tree
fix_temporary_vars_context_r(tree * node,int *,void *)3473 fix_temporary_vars_context_r (tree *node,
3474 			      int  * /*unused*/,
3475 			      void * /*unused1*/)
3476 {
3477   gcc_assert (current_function_decl);
3478 
3479   if (TREE_CODE (*node) == BIND_EXPR)
3480     {
3481       tree var;
3482 
3483       for (var = BIND_EXPR_VARS (*node); var; var = DECL_CHAIN (var))
3484 	if (VAR_P (var)
3485 	  && !DECL_NAME (var)
3486 	  && DECL_ARTIFICIAL (var)
3487 	  && !DECL_CONTEXT (var))
3488 	  DECL_CONTEXT (var) = current_function_decl;
3489     }
3490 
3491   return NULL_TREE;
3492 }
3493 
3494 /* Set up to handle the initialization or destruction of DECL.  If
3495    INITP is nonzero, we are initializing the variable.  Otherwise, we
3496    are destroying it.  */
3497 
3498 static void
one_static_initialization_or_destruction(tree decl,tree init,bool initp)3499 one_static_initialization_or_destruction (tree decl, tree init, bool initp)
3500 {
3501   tree guard_if_stmt = NULL_TREE;
3502   tree guard;
3503 
3504   /* If we are supposed to destruct and there's a trivial destructor,
3505      nothing has to be done.  */
3506   if (!initp
3507       && TYPE_HAS_TRIVIAL_DESTRUCTOR (TREE_TYPE (decl)))
3508     return;
3509 
3510   /* Trick the compiler into thinking we are at the file and line
3511      where DECL was declared so that error-messages make sense, and so
3512      that the debugger will show somewhat sensible file and line
3513      information.  */
3514   input_location = DECL_SOURCE_LOCATION (decl);
3515 
3516   /* Make sure temporary variables in the initialiser all have
3517      their DECL_CONTEXT() set to a value different from NULL_TREE.
3518      This can happen when global variables initialisers are built.
3519      In that case, the DECL_CONTEXT() of the global variables _AND_ of all
3520      the temporary variables that might have been generated in the
3521      accompagning initialisers is NULL_TREE, meaning the variables have been
3522      declared in the global namespace.
3523      What we want to do here is to fix that and make sure the DECL_CONTEXT()
3524      of the temporaries are set to the current function decl.  */
3525   cp_walk_tree_without_duplicates (&init,
3526 				   fix_temporary_vars_context_r,
3527 				   NULL);
3528 
3529   /* Because of:
3530 
3531        [class.access.spec]
3532 
3533        Access control for implicit calls to the constructors,
3534        the conversion functions, or the destructor called to
3535        create and destroy a static data member is performed as
3536        if these calls appeared in the scope of the member's
3537        class.
3538 
3539      we pretend we are in a static member function of the class of
3540      which the DECL is a member.  */
3541   if (member_p (decl))
3542     {
3543       DECL_CONTEXT (current_function_decl) = DECL_CONTEXT (decl);
3544       DECL_STATIC_FUNCTION_P (current_function_decl) = 1;
3545     }
3546 
3547   /* Assume we don't need a guard.  */
3548   guard = NULL_TREE;
3549   /* We need a guard if this is an object with external linkage that
3550      might be initialized in more than one place.  (For example, a
3551      static data member of a template, when the data member requires
3552      construction.)  */
3553   if (NEEDS_GUARD_P (decl))
3554     {
3555       tree guard_cond;
3556 
3557       guard = get_guard (decl);
3558 
3559       /* When using __cxa_atexit, we just check the GUARD as we would
3560 	 for a local static.  */
3561       if (flag_use_cxa_atexit)
3562 	{
3563 	  /* When using __cxa_atexit, we never try to destroy
3564 	     anything from a static destructor.  */
3565 	  gcc_assert (initp);
3566 	  guard_cond = get_guard_cond (guard);
3567 	}
3568       /* If we don't have __cxa_atexit, then we will be running
3569 	 destructors from .fini sections, or their equivalents.  So,
3570 	 we need to know how many times we've tried to initialize this
3571 	 object.  We do initializations only if the GUARD is zero,
3572 	 i.e., if we are the first to initialize the variable.  We do
3573 	 destructions only if the GUARD is one, i.e., if we are the
3574 	 last to destroy the variable.  */
3575       else if (initp)
3576 	guard_cond
3577 	  = cp_build_binary_op (input_location,
3578 				EQ_EXPR,
3579 				cp_build_unary_op (PREINCREMENT_EXPR,
3580 						   guard,
3581 						   /*noconvert=*/1,
3582 						   tf_warning_or_error),
3583 				integer_one_node,
3584 				tf_warning_or_error);
3585       else
3586 	guard_cond
3587 	  = cp_build_binary_op (input_location,
3588 				EQ_EXPR,
3589 				cp_build_unary_op (PREDECREMENT_EXPR,
3590 						   guard,
3591 						   /*noconvert=*/1,
3592 						   tf_warning_or_error),
3593 				integer_zero_node,
3594 				tf_warning_or_error);
3595 
3596       guard_if_stmt = begin_if_stmt ();
3597       finish_if_stmt_cond (guard_cond, guard_if_stmt);
3598     }
3599 
3600 
3601   /* If we're using __cxa_atexit, we have not already set the GUARD,
3602      so we must do so now.  */
3603   if (guard && initp && flag_use_cxa_atexit)
3604     finish_expr_stmt (set_guard (guard));
3605 
3606   /* Perform the initialization or destruction.  */
3607   if (initp)
3608     {
3609       if (init)
3610 	{
3611 	  finish_expr_stmt (init);
3612 	  if (flag_sanitize & SANITIZE_ADDRESS)
3613 	    {
3614 	      varpool_node *vnode = varpool_get_node (decl);
3615 	      if (vnode)
3616 		vnode->dynamically_initialized = 1;
3617 	    }
3618 	}
3619 
3620       /* If we're using __cxa_atexit, register a function that calls the
3621 	 destructor for the object.  */
3622       if (flag_use_cxa_atexit)
3623 	finish_expr_stmt (register_dtor_fn (decl));
3624     }
3625   else
3626     finish_expr_stmt (build_cleanup (decl));
3627 
3628   /* Finish the guard if-stmt, if necessary.  */
3629   if (guard)
3630     {
3631       finish_then_clause (guard_if_stmt);
3632       finish_if_stmt (guard_if_stmt);
3633     }
3634 
3635   /* Now that we're done with DECL we don't need to pretend to be a
3636      member of its class any longer.  */
3637   DECL_CONTEXT (current_function_decl) = NULL_TREE;
3638   DECL_STATIC_FUNCTION_P (current_function_decl) = 0;
3639 }
3640 
3641 /* Generate code to do the initialization or destruction of the decls in VARS,
3642    a TREE_LIST of VAR_DECL with static storage duration.
3643    Whether initialization or destruction is performed is specified by INITP.  */
3644 
3645 static void
do_static_initialization_or_destruction(tree vars,bool initp)3646 do_static_initialization_or_destruction (tree vars, bool initp)
3647 {
3648   tree node, init_if_stmt, cond;
3649 
3650   /* Build the outer if-stmt to check for initialization or destruction.  */
3651   init_if_stmt = begin_if_stmt ();
3652   cond = initp ? integer_one_node : integer_zero_node;
3653   cond = cp_build_binary_op (input_location,
3654 			     EQ_EXPR,
3655 			     initialize_p_decl,
3656 			     cond,
3657 			     tf_warning_or_error);
3658   finish_if_stmt_cond (cond, init_if_stmt);
3659 
3660   /* To make sure dynamic construction doesn't access globals from other
3661      compilation units where they might not be yet constructed, for
3662      -fsanitize=address insert __asan_before_dynamic_init call that
3663      prevents access to either all global variables that need construction
3664      in other compilation units, or at least those that haven't been
3665      initialized yet.  Variables that need dynamic construction in
3666      the current compilation unit are kept accessible.  */
3667   if (flag_sanitize & SANITIZE_ADDRESS)
3668     finish_expr_stmt (asan_dynamic_init_call (/*after_p=*/false));
3669 
3670   node = vars;
3671   do {
3672     tree decl = TREE_VALUE (node);
3673     tree priority_if_stmt;
3674     int priority;
3675     priority_info pi;
3676 
3677     /* If we don't need a destructor, there's nothing to do.  Avoid
3678        creating a possibly empty if-stmt.  */
3679     if (!initp && TYPE_HAS_TRIVIAL_DESTRUCTOR (TREE_TYPE (decl)))
3680       {
3681 	node = TREE_CHAIN (node);
3682 	continue;
3683       }
3684 
3685     /* Remember that we had an initialization or finalization at this
3686        priority.  */
3687     priority = DECL_EFFECTIVE_INIT_PRIORITY (decl);
3688     pi = get_priority_info (priority);
3689     if (initp)
3690       pi->initializations_p = 1;
3691     else
3692       pi->destructions_p = 1;
3693 
3694     /* Conditionalize this initialization on being in the right priority
3695        and being initializing/finalizing appropriately.  */
3696     priority_if_stmt = begin_if_stmt ();
3697     cond = cp_build_binary_op (input_location,
3698 			       EQ_EXPR,
3699 			       priority_decl,
3700 			       build_int_cst (NULL_TREE, priority),
3701 			       tf_warning_or_error);
3702     finish_if_stmt_cond (cond, priority_if_stmt);
3703 
3704     /* Process initializers with same priority.  */
3705     for (; node
3706 	   && DECL_EFFECTIVE_INIT_PRIORITY (TREE_VALUE (node)) == priority;
3707 	 node = TREE_CHAIN (node))
3708       /* Do one initialization or destruction.  */
3709       one_static_initialization_or_destruction (TREE_VALUE (node),
3710 						TREE_PURPOSE (node), initp);
3711 
3712     /* Finish up the priority if-stmt body.  */
3713     finish_then_clause (priority_if_stmt);
3714     finish_if_stmt (priority_if_stmt);
3715 
3716   } while (node);
3717 
3718   /* Revert what __asan_before_dynamic_init did by calling
3719      __asan_after_dynamic_init.  */
3720   if (flag_sanitize & SANITIZE_ADDRESS)
3721     finish_expr_stmt (asan_dynamic_init_call (/*after_p=*/true));
3722 
3723   /* Finish up the init/destruct if-stmt body.  */
3724   finish_then_clause (init_if_stmt);
3725   finish_if_stmt (init_if_stmt);
3726 }
3727 
3728 /* VARS is a list of variables with static storage duration which may
3729    need initialization and/or finalization.  Remove those variables
3730    that don't really need to be initialized or finalized, and return
3731    the resulting list.  The order in which the variables appear in
3732    VARS is in reverse order of the order in which they should actually
3733    be initialized.  The list we return is in the unreversed order;
3734    i.e., the first variable should be initialized first.  */
3735 
3736 static tree
prune_vars_needing_no_initialization(tree * vars)3737 prune_vars_needing_no_initialization (tree *vars)
3738 {
3739   tree *var = vars;
3740   tree result = NULL_TREE;
3741 
3742   while (*var)
3743     {
3744       tree t = *var;
3745       tree decl = TREE_VALUE (t);
3746       tree init = TREE_PURPOSE (t);
3747 
3748       /* Deal gracefully with error.  */
3749       if (decl == error_mark_node)
3750 	{
3751 	  var = &TREE_CHAIN (t);
3752 	  continue;
3753 	}
3754 
3755       /* The only things that can be initialized are variables.  */
3756       gcc_assert (VAR_P (decl));
3757 
3758       /* If this object is not defined, we don't need to do anything
3759 	 here.  */
3760       if (DECL_EXTERNAL (decl))
3761 	{
3762 	  var = &TREE_CHAIN (t);
3763 	  continue;
3764 	}
3765 
3766       /* Also, if the initializer already contains errors, we can bail
3767 	 out now.  */
3768       if (init && TREE_CODE (init) == TREE_LIST
3769 	  && value_member (error_mark_node, init))
3770 	{
3771 	  var = &TREE_CHAIN (t);
3772 	  continue;
3773 	}
3774 
3775       /* This variable is going to need initialization and/or
3776 	 finalization, so we add it to the list.  */
3777       *var = TREE_CHAIN (t);
3778       TREE_CHAIN (t) = result;
3779       result = t;
3780     }
3781 
3782   return result;
3783 }
3784 
3785 /* Make sure we have told the back end about all the variables in
3786    VARS.  */
3787 
3788 static void
write_out_vars(tree vars)3789 write_out_vars (tree vars)
3790 {
3791   tree v;
3792 
3793   for (v = vars; v; v = TREE_CHAIN (v))
3794     {
3795       tree var = TREE_VALUE (v);
3796       if (!var_finalized_p (var))
3797 	{
3798 	  import_export_decl (var);
3799 	  rest_of_decl_compilation (var, 1, 1);
3800 	}
3801     }
3802 }
3803 
3804 /* Generate a static constructor (if CONSTRUCTOR_P) or destructor
3805    (otherwise) that will initialize all global objects with static
3806    storage duration having the indicated PRIORITY.  */
3807 
3808 static void
generate_ctor_or_dtor_function(bool constructor_p,int priority,location_t * locus)3809 generate_ctor_or_dtor_function (bool constructor_p, int priority,
3810 				location_t *locus)
3811 {
3812   char function_key;
3813   tree fndecl;
3814   tree body;
3815   size_t i;
3816 
3817   input_location = *locus;
3818   /* ??? */
3819   /* Was: locus->line++; */
3820 
3821   /* We use `I' to indicate initialization and `D' to indicate
3822      destruction.  */
3823   function_key = constructor_p ? 'I' : 'D';
3824 
3825   /* We emit the function lazily, to avoid generating empty
3826      global constructors and destructors.  */
3827   body = NULL_TREE;
3828 
3829   /* For Objective-C++, we may need to initialize metadata found in this module.
3830      This must be done _before_ any other static initializations.  */
3831   if (c_dialect_objc () && (priority == DEFAULT_INIT_PRIORITY)
3832       && constructor_p && objc_static_init_needed_p ())
3833     {
3834       body = start_objects (function_key, priority);
3835       objc_generate_static_init_call (NULL_TREE);
3836     }
3837 
3838   /* Call the static storage duration function with appropriate
3839      arguments.  */
3840   FOR_EACH_VEC_SAFE_ELT (ssdf_decls, i, fndecl)
3841     {
3842       /* Calls to pure or const functions will expand to nothing.  */
3843       if (! (flags_from_decl_or_type (fndecl) & (ECF_CONST | ECF_PURE)))
3844 	{
3845 	  tree call;
3846 
3847 	  if (! body)
3848 	    body = start_objects (function_key, priority);
3849 
3850 	  call = cp_build_function_call_nary (fndecl, tf_warning_or_error,
3851 					      build_int_cst (NULL_TREE,
3852 							     constructor_p),
3853 					      build_int_cst (NULL_TREE,
3854 							     priority),
3855 					      NULL_TREE);
3856 	  finish_expr_stmt (call);
3857 	}
3858     }
3859 
3860   /* Close out the function.  */
3861   if (body)
3862     finish_objects (function_key, priority, body);
3863 }
3864 
3865 /* Generate constructor and destructor functions for the priority
3866    indicated by N.  */
3867 
3868 static int
generate_ctor_and_dtor_functions_for_priority(splay_tree_node n,void * data)3869 generate_ctor_and_dtor_functions_for_priority (splay_tree_node n, void * data)
3870 {
3871   location_t *locus = (location_t *) data;
3872   int priority = (int) n->key;
3873   priority_info pi = (priority_info) n->value;
3874 
3875   /* Generate the functions themselves, but only if they are really
3876      needed.  */
3877   if (pi->initializations_p)
3878     generate_ctor_or_dtor_function (/*constructor_p=*/true, priority, locus);
3879   if (pi->destructions_p)
3880     generate_ctor_or_dtor_function (/*constructor_p=*/false, priority, locus);
3881 
3882   /* Keep iterating.  */
3883   return 0;
3884 }
3885 
3886 /* Java requires that we be able to reference a local address for a
3887    method, and not be confused by PLT entries.  If hidden aliases are
3888    supported, collect and return all the functions for which we should
3889    emit a hidden alias.  */
3890 
3891 static struct pointer_set_t *
collect_candidates_for_java_method_aliases(void)3892 collect_candidates_for_java_method_aliases (void)
3893 {
3894   struct cgraph_node *node;
3895   struct pointer_set_t *candidates = NULL;
3896 
3897 #ifndef HAVE_GAS_HIDDEN
3898   return candidates;
3899 #endif
3900 
3901   FOR_EACH_FUNCTION (node)
3902     {
3903       tree fndecl = node->decl;
3904 
3905       if (DECL_CLASS_SCOPE_P (fndecl)
3906 	  && TYPE_FOR_JAVA (DECL_CONTEXT (fndecl))
3907 	  && TARGET_USE_LOCAL_THUNK_ALIAS_P (fndecl))
3908 	{
3909 	  if (candidates == NULL)
3910 	    candidates = pointer_set_create ();
3911 	  pointer_set_insert (candidates, fndecl);
3912 	}
3913     }
3914 
3915   return candidates;
3916 }
3917 
3918 
3919 /* Java requires that we be able to reference a local address for a
3920    method, and not be confused by PLT entries.  If hidden aliases are
3921    supported, emit one for each java function that we've emitted.
3922    CANDIDATES is the set of FUNCTION_DECLs that were gathered
3923    by collect_candidates_for_java_method_aliases.  */
3924 
3925 static void
build_java_method_aliases(struct pointer_set_t * candidates)3926 build_java_method_aliases (struct pointer_set_t *candidates)
3927 {
3928   struct cgraph_node *node;
3929 
3930 #ifndef HAVE_GAS_HIDDEN
3931   return;
3932 #endif
3933 
3934   FOR_EACH_FUNCTION (node)
3935     {
3936       tree fndecl = node->decl;
3937 
3938       if (TREE_ASM_WRITTEN (fndecl)
3939 	  && pointer_set_contains (candidates, fndecl))
3940 	{
3941 	  /* Mangle the name in a predictable way; we need to reference
3942 	     this from a java compiled object file.  */
3943 	  tree oid, nid, alias;
3944 	  const char *oname;
3945 	  char *nname;
3946 
3947 	  oid = DECL_ASSEMBLER_NAME (fndecl);
3948 	  oname = IDENTIFIER_POINTER (oid);
3949 	  gcc_assert (oname[0] == '_' && oname[1] == 'Z');
3950 	  nname = ACONCAT (("_ZGA", oname+2, NULL));
3951 	  nid = get_identifier (nname);
3952 
3953 	  alias = make_alias_for (fndecl, nid);
3954 	  TREE_PUBLIC (alias) = 1;
3955 	  DECL_VISIBILITY (alias) = VISIBILITY_HIDDEN;
3956 
3957 	  assemble_alias (alias, oid);
3958 	}
3959     }
3960 }
3961 
3962 /* Return C++ property of T, based on given operation OP.  */
3963 
3964 static int
cpp_check(tree t,cpp_operation op)3965 cpp_check (tree t, cpp_operation op)
3966 {
3967   switch (op)
3968     {
3969       case IS_ABSTRACT:
3970 	return DECL_PURE_VIRTUAL_P (t);
3971       case IS_CONSTRUCTOR:
3972 	return DECL_CONSTRUCTOR_P (t);
3973       case IS_DESTRUCTOR:
3974 	return DECL_DESTRUCTOR_P (t);
3975       case IS_COPY_CONSTRUCTOR:
3976 	return DECL_COPY_CONSTRUCTOR_P (t);
3977       case IS_TEMPLATE:
3978 	return TREE_CODE (t) == TEMPLATE_DECL;
3979       case IS_TRIVIAL:
3980 	return trivial_type_p (t);
3981       default:
3982         return 0;
3983     }
3984 }
3985 
3986 /* Collect source file references recursively, starting from NAMESPC.  */
3987 
3988 static void
collect_source_refs(tree namespc)3989 collect_source_refs (tree namespc)
3990 {
3991   tree t;
3992 
3993   if (!namespc)
3994     return;
3995 
3996   /* Iterate over names in this name space.  */
3997   for (t = NAMESPACE_LEVEL (namespc)->names; t; t = TREE_CHAIN (t))
3998     if (!DECL_IS_BUILTIN (t) )
3999       collect_source_ref (DECL_SOURCE_FILE (t));
4000 
4001   /* Dump siblings, if any */
4002   collect_source_refs (TREE_CHAIN (namespc));
4003 
4004   /* Dump children, if any */
4005   collect_source_refs (NAMESPACE_LEVEL (namespc)->namespaces);
4006 }
4007 
4008 /* Collect decls relevant to SOURCE_FILE from all namespaces recursively,
4009    starting from NAMESPC.  */
4010 
4011 static void
collect_ada_namespace(tree namespc,const char * source_file)4012 collect_ada_namespace (tree namespc, const char *source_file)
4013 {
4014   if (!namespc)
4015     return;
4016 
4017   /* Collect decls from this namespace */
4018   collect_ada_nodes (NAMESPACE_LEVEL (namespc)->names, source_file);
4019 
4020   /* Collect siblings, if any */
4021   collect_ada_namespace (TREE_CHAIN (namespc), source_file);
4022 
4023   /* Collect children, if any */
4024   collect_ada_namespace (NAMESPACE_LEVEL (namespc)->namespaces, source_file);
4025 }
4026 
4027 /* Returns true iff there is a definition available for variable or
4028    function DECL.  */
4029 
4030 static bool
decl_defined_p(tree decl)4031 decl_defined_p (tree decl)
4032 {
4033   if (TREE_CODE (decl) == FUNCTION_DECL)
4034     return (DECL_INITIAL (decl) != NULL_TREE);
4035   else
4036     {
4037       gcc_assert (VAR_P (decl));
4038       return !DECL_EXTERNAL (decl);
4039     }
4040 }
4041 
4042 /* Nonzero for a VAR_DECL whose value can be used in a constant expression.
4043 
4044       [expr.const]
4045 
4046       An integral constant-expression can only involve ... const
4047       variables of integral or enumeration types initialized with
4048       constant expressions ...
4049 
4050       C++0x also allows constexpr variables and temporaries initialized
4051       with constant expressions.  We handle the former here, but the latter
4052       are just folded away in cxx_eval_constant_expression.
4053 
4054    The standard does not require that the expression be non-volatile.
4055    G++ implements the proposed correction in DR 457.  */
4056 
4057 bool
decl_constant_var_p(tree decl)4058 decl_constant_var_p (tree decl)
4059 {
4060   if (!decl_maybe_constant_var_p (decl))
4061     return false;
4062 
4063   /* We don't know if a template static data member is initialized with
4064      a constant expression until we instantiate its initializer.  Even
4065      in the case of a constexpr variable, we can't treat it as a
4066      constant until its initializer is complete in case it's used in
4067      its own initializer.  */
4068   mark_used (decl);
4069   return DECL_INITIALIZED_BY_CONSTANT_EXPRESSION_P (decl);
4070 }
4071 
4072 /* Returns true if DECL could be a symbolic constant variable, depending on
4073    its initializer.  */
4074 
4075 bool
decl_maybe_constant_var_p(tree decl)4076 decl_maybe_constant_var_p (tree decl)
4077 {
4078   tree type = TREE_TYPE (decl);
4079   if (!VAR_P (decl))
4080     return false;
4081   if (DECL_DECLARED_CONSTEXPR_P (decl))
4082     return true;
4083   return (CP_TYPE_CONST_NON_VOLATILE_P (type)
4084 	  && INTEGRAL_OR_ENUMERATION_TYPE_P (type));
4085 }
4086 
4087 /* Complain that DECL uses a type with no linkage.  In C++98 mode this is
4088    called from grokfndecl and grokvardecl; in all modes it is called from
4089    cp_write_global_declarations.  */
4090 
4091 void
no_linkage_error(tree decl)4092 no_linkage_error (tree decl)
4093 {
4094   if (cxx_dialect >= cxx11 && decl_defined_p (decl))
4095     /* In C++11 it's ok if the decl is defined.  */
4096     return;
4097   tree t = no_linkage_check (TREE_TYPE (decl), /*relaxed_p=*/false);
4098   if (t == NULL_TREE)
4099     /* The type that got us on no_linkage_decls must have gotten a name for
4100        linkage purposes.  */;
4101   else if (CLASS_TYPE_P (t) && TYPE_BEING_DEFINED (t))
4102     /* The type might end up having a typedef name for linkage purposes.  */
4103     vec_safe_push (no_linkage_decls, decl);
4104   else if (TYPE_ANONYMOUS_P (t))
4105     {
4106       bool d = false;
4107       if (cxx_dialect >= cxx11)
4108 	d = permerror (DECL_SOURCE_LOCATION (decl), "%q#D, declared using "
4109 		       "anonymous type, is used but never defined", decl);
4110       else if (DECL_EXTERN_C_P (decl))
4111 	/* Allow this; it's pretty common in C.  */;
4112       else if (TREE_CODE (decl) == VAR_DECL)
4113 	/* DRs 132, 319 and 389 seem to indicate types with
4114 	   no linkage can only be used to declare extern "C"
4115 	   entities.  Since it's not always an error in the
4116 	   ISO C++ 90 Standard, we only issue a warning.  */
4117 	d = warning_at (DECL_SOURCE_LOCATION (decl), 0, "anonymous type "
4118 			"with no linkage used to declare variable %q#D with "
4119 			"linkage", decl);
4120       else
4121 	d = permerror (DECL_SOURCE_LOCATION (decl), "anonymous type with no "
4122 		       "linkage used to declare function %q#D with linkage",
4123 		       decl);
4124       if (d && is_typedef_decl (TYPE_NAME (t)))
4125 	inform (DECL_SOURCE_LOCATION (TYPE_NAME (t)), "%q#D does not refer "
4126 		"to the unqualified type, so it is not used for linkage",
4127 		TYPE_NAME (t));
4128     }
4129   else if (cxx_dialect >= cxx11)
4130     permerror (DECL_SOURCE_LOCATION (decl), "%q#D, declared using local type "
4131 	       "%qT, is used but never defined", decl, t);
4132   else if (TREE_CODE (decl) == VAR_DECL)
4133     warning_at (DECL_SOURCE_LOCATION (decl), 0, "type %qT with no linkage "
4134 		"used to declare variable %q#D with linkage", t, decl);
4135   else
4136     permerror (DECL_SOURCE_LOCATION (decl), "type %qT with no linkage used "
4137 	       "to declare function %q#D with linkage", t, decl);
4138 }
4139 
4140 /* Collect declarations from all namespaces relevant to SOURCE_FILE.  */
4141 
4142 static void
collect_all_refs(const char * source_file)4143 collect_all_refs (const char *source_file)
4144 {
4145   collect_ada_namespace (global_namespace, source_file);
4146 }
4147 
4148 /* Clear DECL_EXTERNAL for NODE.  */
4149 
4150 static bool
clear_decl_external(struct cgraph_node * node,void *)4151 clear_decl_external (struct cgraph_node *node, void * /*data*/)
4152 {
4153   DECL_EXTERNAL (node->decl) = 0;
4154   return false;
4155 }
4156 
4157 /* Build up the function to run dynamic initializers for thread_local
4158    variables in this translation unit and alias the init functions for the
4159    individual variables to it.  */
4160 
4161 static void
handle_tls_init(void)4162 handle_tls_init (void)
4163 {
4164   tree vars = prune_vars_needing_no_initialization (&tls_aggregates);
4165   if (vars == NULL_TREE)
4166     return;
4167 
4168   location_t loc = DECL_SOURCE_LOCATION (TREE_VALUE (vars));
4169 
4170   write_out_vars (vars);
4171 
4172   tree guard = build_decl (loc, VAR_DECL, get_identifier ("__tls_guard"),
4173 			   boolean_type_node);
4174   TREE_PUBLIC (guard) = false;
4175   TREE_STATIC (guard) = true;
4176   DECL_ARTIFICIAL (guard) = true;
4177   DECL_IGNORED_P (guard) = true;
4178   TREE_USED (guard) = true;
4179   DECL_TLS_MODEL (guard) = decl_default_tls_model (guard);
4180   pushdecl_top_level_and_finish (guard, NULL_TREE);
4181 
4182   tree fn = get_local_tls_init_fn ();
4183   start_preparsed_function (fn, NULL_TREE, SF_PRE_PARSED);
4184   tree body = begin_function_body ();
4185   tree if_stmt = begin_if_stmt ();
4186   tree cond = cp_build_unary_op (TRUTH_NOT_EXPR, guard, false,
4187 				 tf_warning_or_error);
4188   finish_if_stmt_cond (cond, if_stmt);
4189   finish_expr_stmt (cp_build_modify_expr (guard, NOP_EXPR, boolean_true_node,
4190 					  tf_warning_or_error));
4191   for (; vars; vars = TREE_CHAIN (vars))
4192     {
4193       tree var = TREE_VALUE (vars);
4194       tree init = TREE_PURPOSE (vars);
4195       one_static_initialization_or_destruction (var, init, true);
4196 
4197 #ifdef ASM_OUTPUT_DEF
4198       /* Output init aliases even with -fno-extern-tls-init.  */
4199       if (TREE_PUBLIC (var))
4200 	{
4201           tree single_init_fn = get_tls_init_fn (var);
4202 	  if (single_init_fn == NULL_TREE)
4203 	    continue;
4204 	  cgraph_node *alias
4205 	    = cgraph_same_body_alias (cgraph_get_create_node (fn),
4206 				      single_init_fn, fn);
4207 	  gcc_assert (alias != NULL);
4208 	}
4209 #endif
4210     }
4211 
4212   finish_then_clause (if_stmt);
4213   finish_if_stmt (if_stmt);
4214   finish_function_body (body);
4215   expand_or_defer_fn (finish_function (0));
4216 }
4217 
4218 /* The entire file is now complete.  If requested, dump everything
4219    to a file.  */
4220 
4221 static void
dump_tu(void)4222 dump_tu (void)
4223 {
4224   int flags;
4225   FILE *stream = dump_begin (TDI_tu, &flags);
4226 
4227   if (stream)
4228     {
4229       dump_node (global_namespace, flags & ~TDF_SLIM, stream);
4230       dump_end (TDI_tu, stream);
4231     }
4232 }
4233 
4234 /* Much like the above, but not necessarily defined.  4.9 hack for setting
4235    DECL_COMDAT on DECL_EXTERNAL functions, along with set_comdat.  */
4236 
4237 void
note_comdat_fn(tree decl)4238 note_comdat_fn (tree decl)
4239 {
4240   vec_safe_push (maybe_comdat_fns, decl);
4241 }
4242 
4243 /* DECL is a function with vague linkage that was not
4244    instantiated/synthesized in this translation unit.  Set DECL_COMDAT for
4245    the benefit of can_refer_decl_in_current_unit_p.  */
4246 
4247 static void
set_comdat(tree decl)4248 set_comdat (tree decl)
4249 {
4250   DECL_COMDAT (decl) = true;
4251 
4252   tree clone;
4253   FOR_EACH_CLONE (clone, decl)
4254     set_comdat (clone);
4255 
4256   if (DECL_VIRTUAL_P (decl))
4257     for (tree thunk = DECL_THUNKS (decl); thunk;
4258 	 thunk = DECL_CHAIN (thunk))
4259       DECL_COMDAT (thunk) = true;
4260 }
4261 
4262 /* This routine is called at the end of compilation.
4263    Its job is to create all the code needed to initialize and
4264    destroy the global aggregates.  We do the destruction
4265    first, since that way we only need to reverse the decls once.  */
4266 
4267 void
cp_write_global_declarations(void)4268 cp_write_global_declarations (void)
4269 {
4270   tree vars;
4271   bool reconsider;
4272   size_t i;
4273   location_t locus;
4274   unsigned ssdf_count = 0;
4275   int retries = 0;
4276   tree decl;
4277   struct pointer_set_t *candidates;
4278 
4279   locus = input_location;
4280   at_eof = 1;
4281 
4282   /* Bad parse errors.  Just forget about it.  */
4283   if (! global_bindings_p () || current_class_type
4284       || !vec_safe_is_empty (decl_namespace_list))
4285     return;
4286 
4287   /* This is the point to write out a PCH if we're doing that.
4288      In that case we do not want to do anything else.  */
4289   if (pch_file)
4290     {
4291       c_common_write_pch ();
4292       dump_tu ();
4293       return;
4294     }
4295 
4296   cgraph_process_same_body_aliases ();
4297 
4298   /* Handle -fdump-ada-spec[-slim] */
4299   if (flag_dump_ada_spec || flag_dump_ada_spec_slim)
4300     {
4301       if (flag_dump_ada_spec_slim)
4302 	collect_source_ref (main_input_filename);
4303       else
4304 	collect_source_refs (global_namespace);
4305 
4306       dump_ada_specs (collect_all_refs, cpp_check);
4307     }
4308 
4309   /* FIXME - huh?  was  input_line -= 1;*/
4310 
4311   timevar_start (TV_PHASE_DEFERRED);
4312 
4313   /* We now have to write out all the stuff we put off writing out.
4314      These include:
4315 
4316        o Template specializations that we have not yet instantiated,
4317 	 but which are needed.
4318        o Initialization and destruction for non-local objects with
4319 	 static storage duration.  (Local objects with static storage
4320 	 duration are initialized when their scope is first entered,
4321 	 and are cleaned up via atexit.)
4322        o Virtual function tables.
4323 
4324      All of these may cause others to be needed.  For example,
4325      instantiating one function may cause another to be needed, and
4326      generating the initializer for an object may cause templates to be
4327      instantiated, etc., etc.  */
4328 
4329   emit_support_tinfos ();
4330 
4331   do
4332     {
4333       tree t;
4334       tree decl;
4335 
4336       reconsider = false;
4337 
4338       /* If there are templates that we've put off instantiating, do
4339 	 them now.  */
4340       instantiate_pending_templates (retries);
4341       ggc_collect ();
4342 
4343       /* Write out virtual tables as required.  Note that writing out
4344 	 the virtual table for a template class may cause the
4345 	 instantiation of members of that class.  If we write out
4346 	 vtables then we remove the class from our list so we don't
4347 	 have to look at it again.  */
4348 
4349       while (keyed_classes != NULL_TREE
4350 	     && maybe_emit_vtables (TREE_VALUE (keyed_classes)))
4351 	{
4352 	  reconsider = true;
4353 	  keyed_classes = TREE_CHAIN (keyed_classes);
4354 	}
4355 
4356       t = keyed_classes;
4357       if (t != NULL_TREE)
4358 	{
4359 	  tree next = TREE_CHAIN (t);
4360 
4361 	  while (next)
4362 	    {
4363 	      if (maybe_emit_vtables (TREE_VALUE (next)))
4364 		{
4365 		  reconsider = true;
4366 		  TREE_CHAIN (t) = TREE_CHAIN (next);
4367 		}
4368 	      else
4369 		t = next;
4370 
4371 	      next = TREE_CHAIN (t);
4372 	    }
4373 	}
4374 
4375       /* Write out needed type info variables.  We have to be careful
4376 	 looping through unemitted decls, because emit_tinfo_decl may
4377 	 cause other variables to be needed. New elements will be
4378 	 appended, and we remove from the vector those that actually
4379 	 get emitted.  */
4380       for (i = unemitted_tinfo_decls->length ();
4381 	   unemitted_tinfo_decls->iterate (--i, &t);)
4382 	if (emit_tinfo_decl (t))
4383 	  {
4384 	    reconsider = true;
4385 	    unemitted_tinfo_decls->unordered_remove (i);
4386 	  }
4387 
4388       /* The list of objects with static storage duration is built up
4389 	 in reverse order.  We clear STATIC_AGGREGATES so that any new
4390 	 aggregates added during the initialization of these will be
4391 	 initialized in the correct order when we next come around the
4392 	 loop.  */
4393       vars = prune_vars_needing_no_initialization (&static_aggregates);
4394 
4395       if (vars)
4396 	{
4397 	  /* We need to start a new initialization function each time
4398 	     through the loop.  That's because we need to know which
4399 	     vtables have been referenced, and TREE_SYMBOL_REFERENCED
4400 	     isn't computed until a function is finished, and written
4401 	     out.  That's a deficiency in the back end.  When this is
4402 	     fixed, these initialization functions could all become
4403 	     inline, with resulting performance improvements.  */
4404 	  tree ssdf_body;
4405 
4406 	  /* Set the line and file, so that it is obviously not from
4407 	     the source file.  */
4408 	  input_location = locus;
4409 	  ssdf_body = start_static_storage_duration_function (ssdf_count);
4410 
4411 	  /* Make sure the back end knows about all the variables.  */
4412 	  write_out_vars (vars);
4413 
4414 	  /* First generate code to do all the initializations.  */
4415 	  if (vars)
4416 	    do_static_initialization_or_destruction (vars, /*initp=*/true);
4417 
4418 	  /* Then, generate code to do all the destructions.  Do these
4419 	     in reverse order so that the most recently constructed
4420 	     variable is the first destroyed.  If we're using
4421 	     __cxa_atexit, then we don't need to do this; functions
4422 	     were registered at initialization time to destroy the
4423 	     local statics.  */
4424 	  if (!flag_use_cxa_atexit && vars)
4425 	    {
4426 	      vars = nreverse (vars);
4427 	      do_static_initialization_or_destruction (vars, /*initp=*/false);
4428 	    }
4429 	  else
4430 	    vars = NULL_TREE;
4431 
4432 	  /* Finish up the static storage duration function for this
4433 	     round.  */
4434 	  input_location = locus;
4435 	  finish_static_storage_duration_function (ssdf_body);
4436 
4437 	  /* All those initializations and finalizations might cause
4438 	     us to need more inline functions, more template
4439 	     instantiations, etc.  */
4440 	  reconsider = true;
4441 	  ssdf_count++;
4442 	  /* ??? was:  locus.line++; */
4443 	}
4444 
4445       /* Now do the same for thread_local variables.  */
4446       handle_tls_init ();
4447 
4448       /* Go through the set of inline functions whose bodies have not
4449 	 been emitted yet.  If out-of-line copies of these functions
4450 	 are required, emit them.  */
4451       FOR_EACH_VEC_SAFE_ELT (deferred_fns, i, decl)
4452 	{
4453 	  /* Does it need synthesizing?  */
4454 	  if (DECL_DEFAULTED_FN (decl) && ! DECL_INITIAL (decl)
4455 	      && (! DECL_REALLY_EXTERN (decl) || possibly_inlined_p (decl)))
4456 	    {
4457 	      /* Even though we're already at the top-level, we push
4458 		 there again.  That way, when we pop back a few lines
4459 		 hence, all of our state is restored.  Otherwise,
4460 		 finish_function doesn't clean things up, and we end
4461 		 up with CURRENT_FUNCTION_DECL set.  */
4462 	      push_to_top_level ();
4463 	      /* The decl's location will mark where it was first
4464 		 needed.  Save that so synthesize method can indicate
4465 		 where it was needed from, in case of error  */
4466 	      input_location = DECL_SOURCE_LOCATION (decl);
4467 	      synthesize_method (decl);
4468 	      pop_from_top_level ();
4469 	      reconsider = true;
4470 	    }
4471 
4472 	  if (!DECL_INITIAL (decl) && decl_tls_wrapper_p (decl))
4473 	    generate_tls_wrapper (decl);
4474 
4475 	  if (!DECL_SAVED_TREE (decl))
4476 	    continue;
4477 
4478 	  /* We lie to the back end, pretending that some functions
4479 	     are not defined when they really are.  This keeps these
4480 	     functions from being put out unnecessarily.  But, we must
4481 	     stop lying when the functions are referenced, or if they
4482 	     are not comdat since they need to be put out now.  If
4483 	     DECL_INTERFACE_KNOWN, then we have already set
4484 	     DECL_EXTERNAL appropriately, so there's no need to check
4485 	     again, and we do not want to clear DECL_EXTERNAL if a
4486 	     previous call to import_export_decl set it.
4487 
4488 	     This is done in a separate for cycle, because if some
4489 	     deferred function is contained in another deferred
4490 	     function later in deferred_fns varray,
4491 	     rest_of_compilation would skip this function and we
4492 	     really cannot expand the same function twice.  */
4493 	  import_export_decl (decl);
4494 	  if (DECL_NOT_REALLY_EXTERN (decl)
4495 	      && DECL_INITIAL (decl)
4496 	      && decl_needed_p (decl))
4497 	    {
4498 	      struct cgraph_node *node, *next;
4499 
4500 	      node = cgraph_get_node (decl);
4501 	      if (node->cpp_implicit_alias)
4502 		node = cgraph_alias_target (node);
4503 
4504 	      cgraph_for_node_and_aliases (node, clear_decl_external,
4505 					   NULL, true);
4506 	      /* If we mark !DECL_EXTERNAL one of the symbols in some comdat
4507 		 group, we need to mark all symbols in the same comdat group
4508 		 that way.  */
4509 	      if (node->same_comdat_group)
4510 		for (next = cgraph (node->same_comdat_group);
4511 		     next != node;
4512 		     next = cgraph (next->same_comdat_group))
4513 	          cgraph_for_node_and_aliases (next, clear_decl_external,
4514 					       NULL, true);
4515 	    }
4516 
4517 	  /* If we're going to need to write this function out, and
4518 	     there's already a body for it, create RTL for it now.
4519 	     (There might be no body if this is a method we haven't
4520 	     gotten around to synthesizing yet.)  */
4521 	  if (!DECL_EXTERNAL (decl)
4522 	      && decl_needed_p (decl)
4523 	      && !TREE_ASM_WRITTEN (decl)
4524 	      && !cgraph_get_node (decl)->definition)
4525 	    {
4526 	      /* We will output the function; no longer consider it in this
4527 		 loop.  */
4528 	      DECL_DEFER_OUTPUT (decl) = 0;
4529 	      /* Generate RTL for this function now that we know we
4530 		 need it.  */
4531 	      expand_or_defer_fn (decl);
4532 	      /* If we're compiling -fsyntax-only pretend that this
4533 		 function has been written out so that we don't try to
4534 		 expand it again.  */
4535 	      if (flag_syntax_only)
4536 		TREE_ASM_WRITTEN (decl) = 1;
4537 	      reconsider = true;
4538 	    }
4539 	}
4540 
4541       if (walk_namespaces (wrapup_globals_for_namespace, /*data=*/0))
4542 	reconsider = true;
4543 
4544       /* Static data members are just like namespace-scope globals.  */
4545       FOR_EACH_VEC_SAFE_ELT (pending_statics, i, decl)
4546 	{
4547 	  if (var_finalized_p (decl) || DECL_REALLY_EXTERN (decl)
4548 	      /* Don't write it out if we haven't seen a definition.  */
4549 	      || DECL_IN_AGGR_P (decl))
4550 	    continue;
4551 	  import_export_decl (decl);
4552 	  /* If this static data member is needed, provide it to the
4553 	     back end.  */
4554 	  if (DECL_NOT_REALLY_EXTERN (decl) && decl_needed_p (decl))
4555 	    DECL_EXTERNAL (decl) = 0;
4556 	}
4557       if (vec_safe_length (pending_statics) != 0
4558 	  && wrapup_global_declarations (pending_statics->address (),
4559 					 pending_statics->length ()))
4560 	reconsider = true;
4561 
4562       retries++;
4563     }
4564   while (reconsider);
4565 
4566   /* All used inline functions must have a definition at this point.  */
4567   FOR_EACH_VEC_SAFE_ELT (deferred_fns, i, decl)
4568     {
4569       if (/* Check online inline functions that were actually used.  */
4570 	  DECL_ODR_USED (decl) && DECL_DECLARED_INLINE_P (decl)
4571 	  /* If the definition actually was available here, then the
4572 	     fact that the function was not defined merely represents
4573 	     that for some reason (use of a template repository,
4574 	     #pragma interface, etc.) we decided not to emit the
4575 	     definition here.  */
4576 	  && !DECL_INITIAL (decl)
4577 	  /* Don't complain if the template was defined.  */
4578 	  && !(DECL_TEMPLATE_INSTANTIATION (decl)
4579 	       && DECL_INITIAL (DECL_TEMPLATE_RESULT
4580 				(template_for_substitution (decl)))))
4581 	{
4582 	  warning (0, "inline function %q+D used but never defined", decl);
4583 	  /* Avoid a duplicate warning from check_global_declaration_1.  */
4584 	  TREE_NO_WARNING (decl) = 1;
4585 	}
4586     }
4587 
4588   /* So must decls that use a type with no linkage.  */
4589   FOR_EACH_VEC_SAFE_ELT (no_linkage_decls, i, decl)
4590     no_linkage_error (decl);
4591 
4592   /* Then, do the Objective-C stuff.  This is where all the
4593      Objective-C module stuff gets generated (symtab,
4594      class/protocol/selector lists etc).  This must be done after C++
4595      templates, destructors etc. so that selectors used in C++
4596      templates are properly allocated.  */
4597   if (c_dialect_objc ())
4598     objc_write_global_declarations ();
4599 
4600   /* We give C linkage to static constructors and destructors.  */
4601   push_lang_context (lang_name_c);
4602 
4603   /* Generate initialization and destruction functions for all
4604      priorities for which they are required.  */
4605   if (priority_info_map)
4606     splay_tree_foreach (priority_info_map,
4607 			generate_ctor_and_dtor_functions_for_priority,
4608 			/*data=*/&locus);
4609   else if (c_dialect_objc () && objc_static_init_needed_p ())
4610     /* If this is obj-c++ and we need a static init, call
4611        generate_ctor_or_dtor_function.  */
4612     generate_ctor_or_dtor_function (/*constructor_p=*/true,
4613 				    DEFAULT_INIT_PRIORITY, &locus);
4614 
4615   /* We're done with the splay-tree now.  */
4616   if (priority_info_map)
4617     splay_tree_delete (priority_info_map);
4618 
4619   /* Generate any missing aliases.  */
4620   maybe_apply_pending_pragma_weaks ();
4621 
4622   /* We're done with static constructors, so we can go back to "C++"
4623      linkage now.  */
4624   pop_lang_context ();
4625 
4626   /* Collect candidates for Java hidden aliases.  */
4627   candidates = collect_candidates_for_java_method_aliases ();
4628 
4629   timevar_stop (TV_PHASE_DEFERRED);
4630   timevar_start (TV_PHASE_OPT_GEN);
4631 
4632   if (flag_vtable_verify)
4633     {
4634       vtv_recover_class_info ();
4635       vtv_compute_class_hierarchy_transitive_closure ();
4636       vtv_build_vtable_verify_fndecl ();
4637     }
4638 
4639   FOR_EACH_VEC_SAFE_ELT (maybe_comdat_fns, i, decl)
4640     if (!DECL_COMDAT (decl) && vague_linkage_p (decl))
4641       set_comdat (decl);
4642 
4643   finalize_compilation_unit ();
4644 
4645   if (flag_vtable_verify)
4646     {
4647       /* Generate the special constructor initialization function that
4648          calls __VLTRegisterPairs, and give it a very high
4649          initialization priority.  This must be done after
4650          finalize_compilation_unit so that we have accurate
4651          information about which vtable will actually be emitted.  */
4652       vtv_generate_init_routine ();
4653     }
4654 
4655   timevar_stop (TV_PHASE_OPT_GEN);
4656   timevar_start (TV_PHASE_CHECK_DBGINFO);
4657 
4658   /* Now, issue warnings about static, but not defined, functions,
4659      etc., and emit debugging information.  */
4660   walk_namespaces (wrapup_globals_for_namespace, /*data=*/&reconsider);
4661   if (vec_safe_length (pending_statics) != 0)
4662     {
4663       check_global_declarations (pending_statics->address (),
4664 				 pending_statics->length ());
4665       emit_debug_global_declarations (pending_statics->address (),
4666 				      pending_statics->length ());
4667     }
4668 
4669   perform_deferred_noexcept_checks ();
4670 
4671   /* Generate hidden aliases for Java.  */
4672   if (candidates)
4673     {
4674       build_java_method_aliases (candidates);
4675       pointer_set_destroy (candidates);
4676     }
4677 
4678   finish_repo ();
4679 
4680   /* The entire file is now complete.  If requested, dump everything
4681      to a file.  */
4682   dump_tu ();
4683 
4684   if (flag_detailed_statistics)
4685     {
4686       dump_tree_statistics ();
4687       dump_time_statistics ();
4688     }
4689   input_location = locus;
4690 
4691 #ifdef ENABLE_CHECKING
4692   validate_conversion_obstack ();
4693 #endif /* ENABLE_CHECKING */
4694 
4695   timevar_stop (TV_PHASE_CHECK_DBGINFO);
4696 }
4697 
4698 /* FN is an OFFSET_REF, DOTSTAR_EXPR or MEMBER_REF indicating the
4699    function to call in parse-tree form; it has not yet been
4700    semantically analyzed.  ARGS are the arguments to the function.
4701    They have already been semantically analyzed.  This may change
4702    ARGS.  */
4703 
4704 tree
build_offset_ref_call_from_tree(tree fn,vec<tree,va_gc> ** args,tsubst_flags_t complain)4705 build_offset_ref_call_from_tree (tree fn, vec<tree, va_gc> **args,
4706 				 tsubst_flags_t complain)
4707 {
4708   tree orig_fn;
4709   vec<tree, va_gc> *orig_args = NULL;
4710   tree expr;
4711   tree object;
4712 
4713   orig_fn = fn;
4714   object = TREE_OPERAND (fn, 0);
4715 
4716   if (processing_template_decl)
4717     {
4718       gcc_assert (TREE_CODE (fn) == DOTSTAR_EXPR
4719 		  || TREE_CODE (fn) == MEMBER_REF);
4720       if (type_dependent_expression_p (fn)
4721 	  || any_type_dependent_arguments_p (*args))
4722 	return build_nt_call_vec (fn, *args);
4723 
4724       orig_args = make_tree_vector_copy (*args);
4725 
4726       /* Transform the arguments and add the implicit "this"
4727 	 parameter.  That must be done before the FN is transformed
4728 	 because we depend on the form of FN.  */
4729       make_args_non_dependent (*args);
4730       object = build_non_dependent_expr (object);
4731       if (TREE_CODE (TREE_TYPE (fn)) == METHOD_TYPE)
4732 	{
4733 	  if (TREE_CODE (fn) == DOTSTAR_EXPR)
4734 	    object = cp_build_addr_expr (object, complain);
4735 	  vec_safe_insert (*args, 0, object);
4736 	}
4737       /* Now that the arguments are done, transform FN.  */
4738       fn = build_non_dependent_expr (fn);
4739     }
4740 
4741   /* A qualified name corresponding to a bound pointer-to-member is
4742      represented as an OFFSET_REF:
4743 
4744 	struct B { void g(); };
4745 	void (B::*p)();
4746 	void B::g() { (this->*p)(); }  */
4747   if (TREE_CODE (fn) == OFFSET_REF)
4748     {
4749       tree object_addr = cp_build_addr_expr (object, complain);
4750       fn = TREE_OPERAND (fn, 1);
4751       fn = get_member_function_from_ptrfunc (&object_addr, fn,
4752 					     complain);
4753       vec_safe_insert (*args, 0, object_addr);
4754     }
4755 
4756   if (CLASS_TYPE_P (TREE_TYPE (fn)))
4757     expr = build_op_call (fn, args, complain);
4758   else
4759     expr = cp_build_function_call_vec (fn, args, complain);
4760   if (processing_template_decl && expr != error_mark_node)
4761     expr = build_min_non_dep_call_vec (expr, orig_fn, orig_args);
4762 
4763   if (orig_args != NULL)
4764     release_tree_vector (orig_args);
4765 
4766   return expr;
4767 }
4768 
4769 
4770 void
check_default_args(tree x)4771 check_default_args (tree x)
4772 {
4773   tree arg = TYPE_ARG_TYPES (TREE_TYPE (x));
4774   bool saw_def = false;
4775   int i = 0 - (TREE_CODE (TREE_TYPE (x)) == METHOD_TYPE);
4776   for (; arg && arg != void_list_node; arg = TREE_CHAIN (arg), ++i)
4777     {
4778       if (TREE_PURPOSE (arg))
4779 	saw_def = true;
4780       else if (saw_def && !PACK_EXPANSION_P (TREE_VALUE (arg)))
4781 	{
4782 	  error ("default argument missing for parameter %P of %q+#D", i, x);
4783 	  TREE_PURPOSE (arg) = error_mark_node;
4784 	}
4785     }
4786 }
4787 
4788 /* Return true if function DECL can be inlined.  This is used to force
4789    instantiation of methods that might be interesting for inlining.  */
4790 bool
possibly_inlined_p(tree decl)4791 possibly_inlined_p (tree decl)
4792 {
4793   gcc_assert (TREE_CODE (decl) == FUNCTION_DECL);
4794   if (DECL_UNINLINABLE (decl))
4795     return false;
4796   if (!optimize || pragma_java_exceptions)
4797     return DECL_DECLARED_INLINE_P (decl);
4798   /* When optimizing, we might inline everything when flatten
4799      attribute or heuristics inlining for size or autoinlining
4800      is used.  */
4801   return true;
4802 }
4803 
4804 /* Mark DECL (either a _DECL or a BASELINK) as "used" in the program.
4805    If DECL is a specialization or implicitly declared class member,
4806    generate the actual definition.  Return false if something goes
4807    wrong, true otherwise.  */
4808 
4809 bool
mark_used(tree decl,tsubst_flags_t complain)4810 mark_used (tree decl, tsubst_flags_t complain)
4811 {
4812   /* If DECL is a BASELINK for a single function, then treat it just
4813      like the DECL for the function.  Otherwise, if the BASELINK is
4814      for an overloaded function, we don't know which function was
4815      actually used until after overload resolution.  */
4816   if (BASELINK_P (decl))
4817     {
4818       decl = BASELINK_FUNCTIONS (decl);
4819       if (really_overloaded_fn (decl))
4820 	return true;
4821       decl = OVL_CURRENT (decl);
4822     }
4823 
4824   /* Set TREE_USED for the benefit of -Wunused.  */
4825   TREE_USED (decl) = 1;
4826   if (DECL_CLONED_FUNCTION_P (decl))
4827     TREE_USED (DECL_CLONED_FUNCTION (decl)) = 1;
4828 
4829   /* Mark enumeration types as used.  */
4830   if (TREE_CODE (decl) == CONST_DECL)
4831     used_types_insert (DECL_CONTEXT (decl));
4832 
4833   if (TREE_CODE (decl) == FUNCTION_DECL
4834       && DECL_DELETED_FN (decl))
4835     {
4836       if (DECL_ARTIFICIAL (decl))
4837 	{
4838 	  if (DECL_OVERLOADED_OPERATOR_P (decl) == TYPE_EXPR
4839 	      && LAMBDA_TYPE_P (DECL_CONTEXT (decl)))
4840 	    {
4841 	      /* We mark a lambda conversion op as deleted if we can't
4842 		 generate it properly; see maybe_add_lambda_conv_op.  */
4843 	      sorry ("converting lambda which uses %<...%> to "
4844 		     "function pointer");
4845 	      return false;
4846 	    }
4847 	}
4848       if (complain & tf_error)
4849 	{
4850 	  error ("use of deleted function %qD", decl);
4851 	  if (!maybe_explain_implicit_delete (decl))
4852 	    inform (DECL_SOURCE_LOCATION (decl), "declared here");
4853 	}
4854       return false;
4855     }
4856 
4857   /* We can only check DECL_ODR_USED on variables or functions with
4858      DECL_LANG_SPECIFIC set, and these are also the only decls that we
4859      might need special handling for.  */
4860   if (!VAR_OR_FUNCTION_DECL_P (decl)
4861       || DECL_LANG_SPECIFIC (decl) == NULL
4862       || DECL_THUNK_P (decl))
4863     {
4864       if (!processing_template_decl && type_uses_auto (TREE_TYPE (decl)))
4865 	{
4866 	  if (complain & tf_error)
4867 	    error ("use of %qD before deduction of %<auto%>", decl);
4868 	  return false;
4869 	}
4870       return true;
4871     }
4872 
4873   /* We only want to do this processing once.  We don't need to keep trying
4874      to instantiate inline templates, because unit-at-a-time will make sure
4875      we get them compiled before functions that want to inline them.  */
4876   if (DECL_ODR_USED (decl))
4877     return true;
4878 
4879   /* If within finish_function, defer the rest until that function
4880      finishes, otherwise it might recurse.  */
4881   if (defer_mark_used_calls)
4882     {
4883       vec_safe_push (deferred_mark_used_calls, decl);
4884       return true;
4885     }
4886 
4887   if (TREE_CODE (decl) == FUNCTION_DECL)
4888     maybe_instantiate_noexcept (decl);
4889 
4890   /* Normally, we can wait until instantiation-time to synthesize DECL.
4891      However, if DECL is a static data member initialized with a constant
4892      or a constexpr function, we need it right now because a reference to
4893      such a data member or a call to such function is not value-dependent.
4894      For a function that uses auto in the return type, we need to instantiate
4895      it to find out its type.  For OpenMP user defined reductions, we need
4896      them instantiated for reduction clauses which inline them by hand
4897      directly.  */
4898   if (DECL_LANG_SPECIFIC (decl)
4899       && DECL_TEMPLATE_INFO (decl)
4900       && (decl_maybe_constant_var_p (decl)
4901 	  || (TREE_CODE (decl) == FUNCTION_DECL
4902 	      && (DECL_DECLARED_CONSTEXPR_P (decl)
4903 		  || DECL_OMP_DECLARE_REDUCTION_P (decl)))
4904 	  || undeduced_auto_decl (decl))
4905       && !uses_template_parms (DECL_TI_ARGS (decl)))
4906     {
4907       /* Instantiating a function will result in garbage collection.  We
4908 	 must treat this situation as if we were within the body of a
4909 	 function so as to avoid collecting live data only referenced from
4910 	 the stack (such as overload resolution candidates).  */
4911       ++function_depth;
4912       instantiate_decl (decl, /*defer_ok=*/false,
4913 			/*expl_inst_class_mem_p=*/false);
4914       --function_depth;
4915     }
4916 
4917   if (processing_template_decl)
4918     return true;
4919 
4920   /* Check this too in case we're within fold_non_dependent_expr.  */
4921   if (DECL_TEMPLATE_INFO (decl)
4922       && uses_template_parms (DECL_TI_ARGS (decl)))
4923     return true;
4924 
4925   require_deduced_type (decl);
4926 
4927   /* If we don't need a value, then we don't need to synthesize DECL.  */
4928   if (cp_unevaluated_operand != 0)
4929     return true;
4930 
4931   DECL_ODR_USED (decl) = 1;
4932   if (DECL_CLONED_FUNCTION_P (decl))
4933     DECL_ODR_USED (DECL_CLONED_FUNCTION (decl)) = 1;
4934 
4935   /* DR 757: A type without linkage shall not be used as the type of a
4936      variable or function with linkage, unless
4937    o the variable or function has extern "C" linkage (7.5 [dcl.link]), or
4938    o the variable or function is not used (3.2 [basic.def.odr]) or is
4939    defined in the same translation unit.  */
4940   if (cxx_dialect > cxx98
4941       && decl_linkage (decl) != lk_none
4942       && !DECL_EXTERN_C_P (decl)
4943       && !DECL_ARTIFICIAL (decl)
4944       && !decl_defined_p (decl)
4945       && no_linkage_check (TREE_TYPE (decl), /*relaxed_p=*/false))
4946     {
4947       if (is_local_extern (decl))
4948 	/* There's no way to define a local extern, and adding it to
4949 	   the vector interferes with GC, so give an error now.  */
4950 	no_linkage_error (decl);
4951       else
4952 	vec_safe_push (no_linkage_decls, decl);
4953     }
4954 
4955   if (TREE_CODE (decl) == FUNCTION_DECL && DECL_DECLARED_INLINE_P (decl)
4956       && !DECL_INITIAL (decl) && !DECL_ARTIFICIAL (decl))
4957     /* Remember it, so we can check it was defined.  */
4958     note_vague_linkage_fn (decl);
4959 
4960   /* Is it a synthesized method that needs to be synthesized?  */
4961   if (TREE_CODE (decl) == FUNCTION_DECL
4962       && DECL_NONSTATIC_MEMBER_FUNCTION_P (decl)
4963       && DECL_DEFAULTED_FN (decl)
4964       /* A function defaulted outside the class is synthesized either by
4965 	 cp_finish_decl or instantiate_decl.  */
4966       && !DECL_DEFAULTED_OUTSIDE_CLASS_P (decl)
4967       && ! DECL_INITIAL (decl))
4968     {
4969       /* Defer virtual destructors so that thunks get the right
4970 	 linkage.  */
4971       if (DECL_VIRTUAL_P (decl) && !at_eof)
4972 	{
4973 	  note_vague_linkage_fn (decl);
4974 	  return true;
4975 	}
4976 
4977       /* Remember the current location for a function we will end up
4978 	 synthesizing.  Then we can inform the user where it was
4979 	 required in the case of error.  */
4980       DECL_SOURCE_LOCATION (decl) = input_location;
4981 
4982       /* Synthesizing an implicitly defined member function will result in
4983 	 garbage collection.  We must treat this situation as if we were
4984 	 within the body of a function so as to avoid collecting live data
4985 	 on the stack (such as overload resolution candidates).
4986 
4987          We could just let cp_write_global_declarations handle synthesizing
4988          this function by adding it to deferred_fns, but doing
4989          it at the use site produces better error messages.  */
4990       ++function_depth;
4991       synthesize_method (decl);
4992       --function_depth;
4993       /* If this is a synthesized method we don't need to
4994 	 do the instantiation test below.  */
4995     }
4996   else if (VAR_OR_FUNCTION_DECL_P (decl)
4997 	   && DECL_TEMPLATE_INFO (decl)
4998 	   && (!DECL_EXPLICIT_INSTANTIATION (decl)
4999 	       || always_instantiate_p (decl)))
5000     /* If this is a function or variable that is an instance of some
5001        template, we now know that we will need to actually do the
5002        instantiation. We check that DECL is not an explicit
5003        instantiation because that is not checked in instantiate_decl.
5004 
5005        We put off instantiating functions in order to improve compile
5006        times.  Maintaining a stack of active functions is expensive,
5007        and the inliner knows to instantiate any functions it might
5008        need.  Therefore, we always try to defer instantiation.  */
5009     {
5010       ++function_depth;
5011       instantiate_decl (decl, /*defer_ok=*/true,
5012 			/*expl_inst_class_mem_p=*/false);
5013       --function_depth;
5014     }
5015 
5016   return true;
5017 }
5018 
5019 bool
mark_used(tree decl)5020 mark_used (tree decl)
5021 {
5022   return mark_used (decl, tf_warning_or_error);
5023 }
5024 
5025 tree
vtv_start_verification_constructor_init_function(void)5026 vtv_start_verification_constructor_init_function (void)
5027 {
5028   return start_objects ('I', MAX_RESERVED_INIT_PRIORITY - 1);
5029 }
5030 
5031 tree
vtv_finish_verification_constructor_init_function(tree function_body)5032 vtv_finish_verification_constructor_init_function (tree function_body)
5033 {
5034   tree fn;
5035 
5036   finish_compound_stmt (function_body);
5037   fn = finish_function (0);
5038   DECL_STATIC_CONSTRUCTOR (fn) = 1;
5039   decl_init_priority_insert (fn, MAX_RESERVED_INIT_PRIORITY - 1);
5040 
5041   return fn;
5042 }
5043 
5044 #include "gt-cp-decl2.h"
5045