xref: /openbsd-src/gnu/gcc/gcc/cp/decl2.c (revision 8529ddd3cf8b8ffce3ab6c5b64acddb7831726a7)
1 /* Process declarations and variables for C++ compiler.
2    Copyright (C) 1988, 1992, 1993, 1994, 1995, 1996, 1997, 1998,
3    1999, 2000, 2001, 2002, 2003, 2004, 2005  Free Software Foundation, Inc.
4    Hacked by Michael Tiemann (tiemann@cygnus.com)
5 
6 This file is part of GCC.
7 
8 GCC is free software; you can redistribute it and/or modify
9 it under the terms of the GNU General Public License as published by
10 the Free Software Foundation; either version 2, or (at your option)
11 any later version.
12 
13 GCC is distributed in the hope that it will be useful,
14 but WITHOUT ANY WARRANTY; without even the implied warranty of
15 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
16 GNU General Public License for more details.
17 
18 You should have received a copy of the GNU General Public License
19 along with GCC; see the file COPYING.  If not, write to
20 the Free Software Foundation, 51 Franklin Street, Fifth Floor,
21 Boston, MA 02110-1301, USA.  */
22 
23 
24 /* Process declarations and symbol lookup for C++ front end.
25    Also constructs types; the standard scalar types at initialization,
26    and structure, union, array and enum types when they are declared.  */
27 
28 /* ??? not all decl nodes are given the most useful possible
29    line numbers.  For example, the CONST_DECLs for enum values.  */
30 
31 #include "config.h"
32 #include "system.h"
33 #include "coretypes.h"
34 #include "tm.h"
35 #include "tree.h"
36 #include "rtl.h"
37 #include "expr.h"
38 #include "flags.h"
39 #include "cp-tree.h"
40 #include "decl.h"
41 #include "output.h"
42 #include "except.h"
43 #include "toplev.h"
44 #include "timevar.h"
45 #include "cpplib.h"
46 #include "target.h"
47 #include "c-common.h"
48 #include "tree-mudflap.h"
49 #include "cgraph.h"
50 #include "tree-inline.h"
51 #include "c-pragma.h"
52 #include "tree-dump.h"
53 #include "intl.h"
54 
55 extern cpp_reader *parse_in;
56 
57 /* This structure contains information about the initializations
58    and/or destructions required for a particular priority level.  */
59 typedef struct priority_info_s {
60   /* Nonzero if there have been any initializations at this priority
61      throughout the translation unit.  */
62   int initializations_p;
63   /* Nonzero if there have been any destructions at this priority
64      throughout the translation unit.  */
65   int destructions_p;
66 } *priority_info;
67 
68 static void mark_vtable_entries (tree);
69 static bool maybe_emit_vtables (tree);
70 static bool acceptable_java_type (tree);
71 static tree start_objects (int, int);
72 static void finish_objects (int, int, tree);
73 static tree start_static_storage_duration_function (unsigned);
74 static void finish_static_storage_duration_function (tree);
75 static priority_info get_priority_info (int);
76 static void do_static_initialization_or_destruction (tree, bool);
77 static void one_static_initialization_or_destruction (tree, tree, bool);
78 static void generate_ctor_or_dtor_function (bool, int, location_t *);
79 static int generate_ctor_and_dtor_functions_for_priority (splay_tree_node,
80 							  void *);
81 static tree prune_vars_needing_no_initialization (tree *);
82 static void write_out_vars (tree);
83 static void import_export_class (tree);
84 static tree get_guard_bits (tree);
85 static void determine_visibility_from_class (tree, tree);
86 
87 /* A list of static class variables.  This is needed, because a
88    static class variable can be declared inside the class without
89    an initializer, and then initialized, statically, outside the class.  */
90 static GTY(()) VEC(tree,gc) *pending_statics;
91 
92 /* A list of functions which were declared inline, but which we
93    may need to emit outline anyway.  */
94 static GTY(()) VEC(tree,gc) *deferred_fns;
95 
96 /* Nonzero if we're done parsing and into end-of-file activities.  */
97 
98 int at_eof;
99 
100 /* Functions called along with real static constructors and destructors.  */
101 
102 tree static_ctors;
103 tree static_dtors;
104 
105 
106 
107 /* Return a member function type (a METHOD_TYPE), given FNTYPE (a
108    FUNCTION_TYPE), CTYPE (class type), and QUALS (the cv-qualifiers
109    that apply to the function).  */
110 
111 tree
build_memfn_type(tree fntype,tree ctype,cp_cv_quals quals)112 build_memfn_type (tree fntype, tree ctype, cp_cv_quals quals)
113 {
114   tree raises;
115   int type_quals;
116 
117   if (fntype == error_mark_node || ctype == error_mark_node)
118     return error_mark_node;
119 
120   type_quals = quals & ~TYPE_QUAL_RESTRICT;
121   ctype = cp_build_qualified_type (ctype, type_quals);
122   fntype = build_method_type_directly (ctype, TREE_TYPE (fntype),
123 				       (TREE_CODE (fntype) == METHOD_TYPE
124 					? TREE_CHAIN (TYPE_ARG_TYPES (fntype))
125 					: TYPE_ARG_TYPES (fntype)));
126   raises = TYPE_RAISES_EXCEPTIONS (fntype);
127   if (raises)
128     fntype = build_exception_variant (fntype, raises);
129 
130   return fntype;
131 }
132 
133 /* Build a PARM_DECL with NAME and TYPE, and set DECL_ARG_TYPE
134    appropriately.  */
135 
136 tree
cp_build_parm_decl(tree name,tree type)137 cp_build_parm_decl (tree name, tree type)
138 {
139   tree parm = build_decl (PARM_DECL, name, type);
140   /* DECL_ARG_TYPE is only used by the back end and the back end never
141      sees templates.  */
142   if (!processing_template_decl)
143     DECL_ARG_TYPE (parm) = type_passed_as (type);
144   return parm;
145 }
146 
147 /* Returns a PARM_DECL for a parameter of the indicated TYPE, with the
148    indicated NAME.  */
149 
150 tree
build_artificial_parm(tree name,tree type)151 build_artificial_parm (tree name, tree type)
152 {
153   tree parm = cp_build_parm_decl (name, type);
154   DECL_ARTIFICIAL (parm) = 1;
155   /* All our artificial parms are implicitly `const'; they cannot be
156      assigned to.  */
157   TREE_READONLY (parm) = 1;
158   return parm;
159 }
160 
161 /* Constructors for types with virtual baseclasses need an "in-charge" flag
162    saying whether this constructor is responsible for initialization of
163    virtual baseclasses or not.  All destructors also need this "in-charge"
164    flag, which additionally determines whether or not the destructor should
165    free the memory for the object.
166 
167    This function adds the "in-charge" flag to member function FN if
168    appropriate.  It is called from grokclassfn and tsubst.
169    FN must be either a constructor or destructor.
170 
171    The in-charge flag follows the 'this' parameter, and is followed by the
172    VTT parm (if any), then the user-written parms.  */
173 
174 void
maybe_retrofit_in_chrg(tree fn)175 maybe_retrofit_in_chrg (tree fn)
176 {
177   tree basetype, arg_types, parms, parm, fntype;
178 
179   /* If we've already add the in-charge parameter don't do it again.  */
180   if (DECL_HAS_IN_CHARGE_PARM_P (fn))
181     return;
182 
183   /* When processing templates we can't know, in general, whether or
184      not we're going to have virtual baseclasses.  */
185   if (processing_template_decl)
186     return;
187 
188   /* We don't need an in-charge parameter for constructors that don't
189      have virtual bases.  */
190   if (DECL_CONSTRUCTOR_P (fn)
191       && !CLASSTYPE_VBASECLASSES (DECL_CONTEXT (fn)))
192     return;
193 
194   arg_types = TYPE_ARG_TYPES (TREE_TYPE (fn));
195   basetype = TREE_TYPE (TREE_VALUE (arg_types));
196   arg_types = TREE_CHAIN (arg_types);
197 
198   parms = TREE_CHAIN (DECL_ARGUMENTS (fn));
199 
200   /* If this is a subobject constructor or destructor, our caller will
201      pass us a pointer to our VTT.  */
202   if (CLASSTYPE_VBASECLASSES (DECL_CONTEXT (fn)))
203     {
204       parm = build_artificial_parm (vtt_parm_identifier, vtt_parm_type);
205 
206       /* First add it to DECL_ARGUMENTS between 'this' and the real args...  */
207       TREE_CHAIN (parm) = parms;
208       parms = parm;
209 
210       /* ...and then to TYPE_ARG_TYPES.  */
211       arg_types = hash_tree_chain (vtt_parm_type, arg_types);
212 
213       DECL_HAS_VTT_PARM_P (fn) = 1;
214     }
215 
216   /* Then add the in-charge parm (before the VTT parm).  */
217   parm = build_artificial_parm (in_charge_identifier, integer_type_node);
218   TREE_CHAIN (parm) = parms;
219   parms = parm;
220   arg_types = hash_tree_chain (integer_type_node, arg_types);
221 
222   /* Insert our new parameter(s) into the list.  */
223   TREE_CHAIN (DECL_ARGUMENTS (fn)) = parms;
224 
225   /* And rebuild the function type.  */
226   fntype = build_method_type_directly (basetype, TREE_TYPE (TREE_TYPE (fn)),
227 				       arg_types);
228   if (TYPE_RAISES_EXCEPTIONS (TREE_TYPE (fn)))
229     fntype = build_exception_variant (fntype,
230 				      TYPE_RAISES_EXCEPTIONS (TREE_TYPE (fn)));
231   TREE_TYPE (fn) = fntype;
232 
233   /* Now we've got the in-charge parameter.  */
234   DECL_HAS_IN_CHARGE_PARM_P (fn) = 1;
235 }
236 
237 /* Classes overload their constituent function names automatically.
238    When a function name is declared in a record structure,
239    its name is changed to it overloaded name.  Since names for
240    constructors and destructors can conflict, we place a leading
241    '$' for destructors.
242 
243    CNAME is the name of the class we are grokking for.
244 
245    FUNCTION is a FUNCTION_DECL.  It was created by `grokdeclarator'.
246 
247    FLAGS contains bits saying what's special about today's
248    arguments.  1 == DESTRUCTOR.  2 == OPERATOR.
249 
250    If FUNCTION is a destructor, then we must add the `auto-delete' field
251    as a second parameter.  There is some hair associated with the fact
252    that we must "declare" this variable in the manner consistent with the
253    way the rest of the arguments were declared.
254 
255    QUALS are the qualifiers for the this pointer.  */
256 
257 void
grokclassfn(tree ctype,tree function,enum overload_flags flags)258 grokclassfn (tree ctype, tree function, enum overload_flags flags)
259 {
260   tree fn_name = DECL_NAME (function);
261 
262   /* Even within an `extern "C"' block, members get C++ linkage.  See
263      [dcl.link] for details.  */
264   SET_DECL_LANGUAGE (function, lang_cplusplus);
265 
266   if (fn_name == NULL_TREE)
267     {
268       error ("name missing for member function");
269       fn_name = get_identifier ("<anonymous>");
270       DECL_NAME (function) = fn_name;
271     }
272 
273   DECL_CONTEXT (function) = ctype;
274 
275   if (flags == DTOR_FLAG)
276     DECL_DESTRUCTOR_P (function) = 1;
277 
278   if (flags == DTOR_FLAG || DECL_CONSTRUCTOR_P (function))
279     maybe_retrofit_in_chrg (function);
280 }
281 
282 /* Create an ARRAY_REF, checking for the user doing things backwards
283    along the way.  */
284 
285 tree
grok_array_decl(tree array_expr,tree index_exp)286 grok_array_decl (tree array_expr, tree index_exp)
287 {
288   tree type;
289   tree expr;
290   tree orig_array_expr = array_expr;
291   tree orig_index_exp = index_exp;
292 
293   if (error_operand_p (array_expr) || error_operand_p (index_exp))
294     return error_mark_node;
295 
296   if (processing_template_decl)
297     {
298       if (type_dependent_expression_p (array_expr)
299 	  || type_dependent_expression_p (index_exp))
300 	return build_min_nt (ARRAY_REF, array_expr, index_exp,
301 			     NULL_TREE, NULL_TREE);
302       array_expr = build_non_dependent_expr (array_expr);
303       index_exp = build_non_dependent_expr (index_exp);
304     }
305 
306   type = TREE_TYPE (array_expr);
307   gcc_assert (type);
308   type = non_reference (type);
309 
310   /* If they have an `operator[]', use that.  */
311   if (IS_AGGR_TYPE (type) || IS_AGGR_TYPE (TREE_TYPE (index_exp)))
312     expr = build_new_op (ARRAY_REF, LOOKUP_NORMAL,
313 			 array_expr, index_exp, NULL_TREE,
314 			 /*overloaded_p=*/NULL);
315   else
316     {
317       tree p1, p2, i1, i2;
318 
319       /* Otherwise, create an ARRAY_REF for a pointer or array type.
320 	 It is a little-known fact that, if `a' is an array and `i' is
321 	 an int, you can write `i[a]', which means the same thing as
322 	 `a[i]'.  */
323       if (TREE_CODE (type) == ARRAY_TYPE)
324 	p1 = array_expr;
325       else
326 	p1 = build_expr_type_conversion (WANT_POINTER, array_expr, false);
327 
328       if (TREE_CODE (TREE_TYPE (index_exp)) == ARRAY_TYPE)
329 	p2 = index_exp;
330       else
331 	p2 = build_expr_type_conversion (WANT_POINTER, index_exp, false);
332 
333       i1 = build_expr_type_conversion (WANT_INT | WANT_ENUM, array_expr,
334 				       false);
335       i2 = build_expr_type_conversion (WANT_INT | WANT_ENUM, index_exp,
336 				       false);
337 
338       if ((p1 && i2) && (i1 && p2))
339 	error ("ambiguous conversion for array subscript");
340 
341       if (p1 && i2)
342 	array_expr = p1, index_exp = i2;
343       else if (i1 && p2)
344 	array_expr = p2, index_exp = i1;
345       else
346 	{
347 	  error ("invalid types %<%T[%T]%> for array subscript",
348 		 type, TREE_TYPE (index_exp));
349 	  return error_mark_node;
350 	}
351 
352       if (array_expr == error_mark_node || index_exp == error_mark_node)
353 	error ("ambiguous conversion for array subscript");
354 
355       expr = build_array_ref (array_expr, index_exp);
356     }
357   if (processing_template_decl && expr != error_mark_node)
358     return build_min_non_dep (ARRAY_REF, expr, orig_array_expr, orig_index_exp,
359 			      NULL_TREE, NULL_TREE);
360   return expr;
361 }
362 
363 /* Given the cast expression EXP, checking out its validity.   Either return
364    an error_mark_node if there was an unavoidable error, return a cast to
365    void for trying to delete a pointer w/ the value 0, or return the
366    call to delete.  If DOING_VEC is true, we handle things differently
367    for doing an array delete.
368    Implements ARM $5.3.4.  This is called from the parser.  */
369 
370 tree
delete_sanity(tree exp,tree size,bool doing_vec,int use_global_delete)371 delete_sanity (tree exp, tree size, bool doing_vec, int use_global_delete)
372 {
373   tree t, type;
374 
375   if (exp == error_mark_node)
376     return exp;
377 
378   if (processing_template_decl)
379     {
380       t = build_min (DELETE_EXPR, void_type_node, exp, size);
381       DELETE_EXPR_USE_GLOBAL (t) = use_global_delete;
382       DELETE_EXPR_USE_VEC (t) = doing_vec;
383       TREE_SIDE_EFFECTS (t) = 1;
384       return t;
385     }
386 
387   /* An array can't have been allocated by new, so complain.  */
388   if (TREE_CODE (exp) == VAR_DECL
389       && TREE_CODE (TREE_TYPE (exp)) == ARRAY_TYPE)
390     warning (0, "deleting array %q#D", exp);
391 
392   t = build_expr_type_conversion (WANT_POINTER, exp, true);
393 
394   if (t == NULL_TREE || t == error_mark_node)
395     {
396       error ("type %q#T argument given to %<delete%>, expected pointer",
397 	     TREE_TYPE (exp));
398       return error_mark_node;
399     }
400 
401   type = TREE_TYPE (t);
402 
403   /* As of Valley Forge, you can delete a pointer to const.  */
404 
405   /* You can't delete functions.  */
406   if (TREE_CODE (TREE_TYPE (type)) == FUNCTION_TYPE)
407     {
408       error ("cannot delete a function.  Only pointer-to-objects are "
409 	     "valid arguments to %<delete%>");
410       return error_mark_node;
411     }
412 
413   /* Deleting ptr to void is undefined behavior [expr.delete/3].  */
414   if (TREE_CODE (TREE_TYPE (type)) == VOID_TYPE)
415     {
416       warning (0, "deleting %qT is undefined", type);
417       doing_vec = 0;
418     }
419 
420   /* Deleting a pointer with the value zero is valid and has no effect.  */
421   if (integer_zerop (t))
422     return build1 (NOP_EXPR, void_type_node, t);
423 
424   if (doing_vec)
425     return build_vec_delete (t, /*maxindex=*/NULL_TREE,
426 			     sfk_deleting_destructor,
427 			     use_global_delete);
428   else
429     return build_delete (type, t, sfk_deleting_destructor,
430 			 LOOKUP_NORMAL, use_global_delete);
431 }
432 
433 /* Report an error if the indicated template declaration is not the
434    sort of thing that should be a member template.  */
435 
436 void
check_member_template(tree tmpl)437 check_member_template (tree tmpl)
438 {
439   tree decl;
440 
441   gcc_assert (TREE_CODE (tmpl) == TEMPLATE_DECL);
442   decl = DECL_TEMPLATE_RESULT (tmpl);
443 
444   if (TREE_CODE (decl) == FUNCTION_DECL
445       || (TREE_CODE (decl) == TYPE_DECL
446 	  && IS_AGGR_TYPE (TREE_TYPE (decl))))
447     {
448       /* The parser rejects template declarations in local classes.  */
449       gcc_assert (!current_function_decl);
450       /* The parser rejects any use of virtual in a function template.  */
451       gcc_assert (!(TREE_CODE (decl) == FUNCTION_DECL
452 		    && DECL_VIRTUAL_P (decl)));
453 
454       /* The debug-information generating code doesn't know what to do
455 	 with member templates.  */
456       DECL_IGNORED_P (tmpl) = 1;
457     }
458   else
459     error ("template declaration of %q#D", decl);
460 }
461 
462 /* Return true iff TYPE is a valid Java parameter or return type.  */
463 
464 static bool
acceptable_java_type(tree type)465 acceptable_java_type (tree type)
466 {
467   if (type == error_mark_node)
468     return false;
469 
470   if (TREE_CODE (type) == VOID_TYPE || TYPE_FOR_JAVA (type))
471     return true;
472   if (TREE_CODE (type) == POINTER_TYPE || TREE_CODE (type) == REFERENCE_TYPE)
473     {
474       type = TREE_TYPE (type);
475       if (TREE_CODE (type) == RECORD_TYPE)
476 	{
477 	  tree args;  int i;
478 	  if (! TYPE_FOR_JAVA (type))
479 	    return false;
480 	  if (! CLASSTYPE_TEMPLATE_INFO (type))
481 	    return true;
482 	  args = CLASSTYPE_TI_ARGS (type);
483 	  i = TREE_VEC_LENGTH (args);
484 	  while (--i >= 0)
485 	    {
486 	      type = TREE_VEC_ELT (args, i);
487 	      if (TREE_CODE (type) == POINTER_TYPE)
488 		type = TREE_TYPE (type);
489 	      if (! TYPE_FOR_JAVA (type))
490 		return false;
491 	    }
492 	  return true;
493 	}
494     }
495   return false;
496 }
497 
498 /* For a METHOD in a Java class CTYPE, return true if
499    the parameter and return types are valid Java types.
500    Otherwise, print appropriate error messages, and return false.  */
501 
502 bool
check_java_method(tree method)503 check_java_method (tree method)
504 {
505   bool jerr = false;
506   tree arg_types = TYPE_ARG_TYPES (TREE_TYPE (method));
507   tree ret_type = TREE_TYPE (TREE_TYPE (method));
508 
509   if (!acceptable_java_type (ret_type))
510     {
511       error ("Java method %qD has non-Java return type %qT",
512 	     method, ret_type);
513       jerr = true;
514     }
515 
516   arg_types = TREE_CHAIN (arg_types);
517   if (DECL_HAS_IN_CHARGE_PARM_P (method))
518     arg_types = TREE_CHAIN (arg_types);
519   if (DECL_HAS_VTT_PARM_P (method))
520     arg_types = TREE_CHAIN (arg_types);
521 
522   for (; arg_types != NULL_TREE; arg_types = TREE_CHAIN (arg_types))
523     {
524       tree type = TREE_VALUE (arg_types);
525       if (!acceptable_java_type (type))
526 	{
527           if (type != error_mark_node)
528 	    error ("Java method %qD has non-Java parameter type %qT",
529 		   method, type);
530 	  jerr = true;
531 	}
532     }
533   return !jerr;
534 }
535 
536 /* Sanity check: report error if this function FUNCTION is not
537    really a member of the class (CTYPE) it is supposed to belong to.
538    TEMPLATE_PARMS is used to specify the template parameters of a member
539    template passed as FUNCTION_DECL. If the member template is passed as a
540    TEMPLATE_DECL, it can be NULL since the parameters can be extracted
541    from the declaration. If the function is not a function template, it
542    must be NULL.
543    It returns the original declaration for the function, or NULL_TREE
544    if no declaration was found (and an error was emitted).  */
545 
546 tree
check_classfn(tree ctype,tree function,tree template_parms)547 check_classfn (tree ctype, tree function, tree template_parms)
548 {
549   int ix;
550   bool is_template;
551   tree pushed_scope;
552 
553   if (DECL_USE_TEMPLATE (function)
554       && !(TREE_CODE (function) == TEMPLATE_DECL
555 	   && DECL_TEMPLATE_SPECIALIZATION (function))
556       && DECL_MEMBER_TEMPLATE_P (DECL_TI_TEMPLATE (function)))
557     /* Since this is a specialization of a member template,
558        we're not going to find the declaration in the class.
559        For example, in:
560 
561 	 struct S { template <typename T> void f(T); };
562 	 template <> void S::f(int);
563 
564        we're not going to find `S::f(int)', but there's no
565        reason we should, either.  We let our callers know we didn't
566        find the method, but we don't complain.  */
567     return NULL_TREE;
568 
569   /* Basic sanity check: for a template function, the template parameters
570      either were not passed, or they are the same of DECL_TEMPLATE_PARMS.  */
571   if (TREE_CODE (function) == TEMPLATE_DECL)
572     {
573       gcc_assert (!template_parms
574 		  || comp_template_parms (template_parms,
575 					  DECL_TEMPLATE_PARMS (function)));
576       template_parms = DECL_TEMPLATE_PARMS (function);
577     }
578 
579   /* OK, is this a definition of a member template?  */
580   is_template = (template_parms != NULL_TREE);
581 
582   /* We must enter the scope here, because conversion operators are
583      named by target type, and type equivalence relies on typenames
584      resolving within the scope of CTYPE.  */
585   pushed_scope = push_scope (ctype);
586   ix = class_method_index_for_fn (complete_type (ctype), function);
587   if (ix >= 0)
588     {
589       VEC(tree,gc) *methods = CLASSTYPE_METHOD_VEC (ctype);
590       tree fndecls, fndecl = 0;
591       bool is_conv_op;
592       const char *format = NULL;
593 
594       for (fndecls = VEC_index (tree, methods, ix);
595 	   fndecls; fndecls = OVL_NEXT (fndecls))
596 	{
597 	  tree p1, p2;
598 
599 	  fndecl = OVL_CURRENT (fndecls);
600 	  p1 = TYPE_ARG_TYPES (TREE_TYPE (function));
601 	  p2 = TYPE_ARG_TYPES (TREE_TYPE (fndecl));
602 
603 	  /* We cannot simply call decls_match because this doesn't
604 	     work for static member functions that are pretending to
605 	     be methods, and because the name may have been changed by
606 	     asm("new_name").  */
607 
608 	   /* Get rid of the this parameter on functions that become
609 	      static.  */
610 	  if (DECL_STATIC_FUNCTION_P (fndecl)
611 	      && TREE_CODE (TREE_TYPE (function)) == METHOD_TYPE)
612 	    p1 = TREE_CHAIN (p1);
613 
614 	  /* A member template definition only matches a member template
615 	     declaration.  */
616 	  if (is_template != (TREE_CODE (fndecl) == TEMPLATE_DECL))
617 	    continue;
618 
619 	  if (same_type_p (TREE_TYPE (TREE_TYPE (function)),
620 			   TREE_TYPE (TREE_TYPE (fndecl)))
621 	      && compparms (p1, p2)
622 	      && (!is_template
623 		  || comp_template_parms (template_parms,
624 					  DECL_TEMPLATE_PARMS (fndecl)))
625 	      && (DECL_TEMPLATE_SPECIALIZATION (function)
626 		  == DECL_TEMPLATE_SPECIALIZATION (fndecl))
627 	      && (!DECL_TEMPLATE_SPECIALIZATION (function)
628 		  || (DECL_TI_TEMPLATE (function)
629 		      == DECL_TI_TEMPLATE (fndecl))))
630 	    break;
631 	}
632       if (fndecls)
633 	{
634 	  if (pushed_scope)
635 	    pop_scope (pushed_scope);
636 	  return OVL_CURRENT (fndecls);
637 	}
638 
639       error ("prototype for %q#D does not match any in class %qT",
640 	     function, ctype);
641       is_conv_op = DECL_CONV_FN_P (fndecl);
642 
643       if (is_conv_op)
644 	ix = CLASSTYPE_FIRST_CONVERSION_SLOT;
645       fndecls = VEC_index (tree, methods, ix);
646       while (fndecls)
647 	{
648 	  fndecl = OVL_CURRENT (fndecls);
649 	  fndecls = OVL_NEXT (fndecls);
650 
651 	  if (!fndecls && is_conv_op)
652 	    {
653 	      if (VEC_length (tree, methods) > (size_t) ++ix)
654 		{
655 		  fndecls = VEC_index (tree, methods, ix);
656 		  if (!DECL_CONV_FN_P (OVL_CURRENT (fndecls)))
657 		    {
658 		      fndecls = NULL_TREE;
659 		      is_conv_op = false;
660 		    }
661 		}
662 	      else
663 		is_conv_op = false;
664 	    }
665 	  if (format)
666 	    format = "                %+#D";
667 	  else if (fndecls)
668 	    format = N_("candidates are: %+#D");
669 	  else
670 	    format = N_("candidate is: %+#D");
671 	  error (format, fndecl);
672 	}
673     }
674   else if (!COMPLETE_TYPE_P (ctype))
675     cxx_incomplete_type_error (function, ctype);
676   else
677     error ("no %q#D member function declared in class %qT",
678 	   function, ctype);
679 
680   /* If we did not find the method in the class, add it to avoid
681      spurious errors (unless the CTYPE is not yet defined, in which
682      case we'll only confuse ourselves when the function is declared
683      properly within the class.  */
684   if (COMPLETE_TYPE_P (ctype))
685     add_method (ctype, function, NULL_TREE);
686 
687   if (pushed_scope)
688     pop_scope (pushed_scope);
689   return NULL_TREE;
690 }
691 
692 /* DECL is a function with vague linkage.  Remember it so that at the
693    end of the translation unit we can decide whether or not to emit
694    it.  */
695 
696 void
note_vague_linkage_fn(tree decl)697 note_vague_linkage_fn (tree decl)
698 {
699   if (!DECL_DEFERRED_FN (decl))
700     {
701       DECL_DEFERRED_FN (decl) = 1;
702       DECL_DEFER_OUTPUT (decl) = 1;
703       VEC_safe_push (tree, gc, deferred_fns, decl);
704     }
705 }
706 
707 /* We have just processed the DECL, which is a static data member.
708    The other parameters are as for cp_finish_decl.  */
709 
710 void
finish_static_data_member_decl(tree decl,tree init,bool init_const_expr_p,tree asmspec_tree,int flags)711 finish_static_data_member_decl (tree decl,
712 				tree init, bool init_const_expr_p,
713 				tree asmspec_tree,
714 				int flags)
715 {
716   DECL_CONTEXT (decl) = current_class_type;
717 
718   /* We cannot call pushdecl here, because that would fill in the
719      TREE_CHAIN of our decl.  Instead, we modify cp_finish_decl to do
720      the right thing, namely, to put this decl out straight away.  */
721 
722   if (! processing_template_decl)
723     VEC_safe_push (tree, gc, pending_statics, decl);
724 
725   if (LOCAL_CLASS_P (current_class_type))
726     pedwarn ("local class %q#T shall not have static data member %q#D",
727 	     current_class_type, decl);
728 
729   /* Static consts need not be initialized in the class definition.  */
730   if (init != NULL_TREE && TYPE_NEEDS_CONSTRUCTING (TREE_TYPE (decl)))
731     {
732       static int explained = 0;
733 
734       error ("initializer invalid for static member with constructor");
735       if (!explained)
736 	{
737 	  error ("(an out of class initialization is required)");
738 	  explained = 1;
739 	}
740       init = NULL_TREE;
741     }
742   /* Force the compiler to know when an uninitialized static const
743      member is being used.  */
744   if (CP_TYPE_CONST_P (TREE_TYPE (decl)) && init == 0)
745     TREE_USED (decl) = 1;
746   DECL_INITIAL (decl) = init;
747   DECL_IN_AGGR_P (decl) = 1;
748 
749   cp_finish_decl (decl, init, init_const_expr_p, asmspec_tree, flags);
750 }
751 
752 /* DECLARATOR and DECLSPECS correspond to a class member.  The other
753    parameters are as for cp_finish_decl.  Return the DECL for the
754    class member declared.  */
755 
756 tree
grokfield(const cp_declarator * declarator,cp_decl_specifier_seq * declspecs,tree init,bool init_const_expr_p,tree asmspec_tree,tree attrlist)757 grokfield (const cp_declarator *declarator,
758 	   cp_decl_specifier_seq *declspecs,
759 	   tree init, bool init_const_expr_p,
760 	   tree asmspec_tree,
761 	   tree attrlist)
762 {
763   tree value;
764   const char *asmspec = 0;
765   int flags = LOOKUP_ONLYCONVERTING;
766 
767   if (init
768       && TREE_CODE (init) == TREE_LIST
769       && TREE_VALUE (init) == error_mark_node
770       && TREE_CHAIN (init) == NULL_TREE)
771     init = NULL_TREE;
772 
773   value = grokdeclarator (declarator, declspecs, FIELD, init != 0, &attrlist);
774   if (! value || error_operand_p (value))
775     /* friend or constructor went bad.  */
776     return error_mark_node;
777 
778   if (TREE_CODE (value) == TYPE_DECL && init)
779     {
780       error ("typedef %qD is initialized (use __typeof__ instead)", value);
781       init = NULL_TREE;
782     }
783 
784   /* Pass friendly classes back.  */
785   if (value == void_type_node)
786     return value;
787 
788   /* Pass friend decls back.  */
789   if ((TREE_CODE (value) == FUNCTION_DECL
790        || TREE_CODE (value) == TEMPLATE_DECL)
791       && DECL_CONTEXT (value) != current_class_type)
792     return value;
793 
794   if (DECL_NAME (value) != NULL_TREE
795       && IDENTIFIER_POINTER (DECL_NAME (value))[0] == '_'
796       && ! strcmp (IDENTIFIER_POINTER (DECL_NAME (value)), "_vptr"))
797     error ("member %qD conflicts with virtual function table field name",
798 	   value);
799 
800   /* Stash away type declarations.  */
801   if (TREE_CODE (value) == TYPE_DECL)
802     {
803       DECL_NONLOCAL (value) = 1;
804       DECL_CONTEXT (value) = current_class_type;
805 
806       if (processing_template_decl)
807 	value = push_template_decl (value);
808 
809       if (attrlist)
810 	{
811 	  /* Avoid storing attributes in template parameters:
812 	     tsubst is not ready to handle them.  */
813 	  tree type = TREE_TYPE (value);
814 	  if (TREE_CODE (type) == TEMPLATE_TYPE_PARM
815 	      || TREE_CODE (type) == BOUND_TEMPLATE_TEMPLATE_PARM)
816 	    sorry ("applying attributes to template parameters is not implemented");
817 	  else
818 	    cplus_decl_attributes (&value, attrlist, 0);
819 	}
820 
821       return value;
822     }
823 
824   if (DECL_IN_AGGR_P (value))
825     {
826       error ("%qD is already defined in %qT", value, DECL_CONTEXT (value));
827       return void_type_node;
828     }
829 
830   if (asmspec_tree && asmspec_tree != error_mark_node)
831     asmspec = TREE_STRING_POINTER (asmspec_tree);
832 
833   if (init)
834     {
835       if (TREE_CODE (value) == FUNCTION_DECL)
836 	{
837 	  /* Initializers for functions are rejected early in the parser.
838 	     If we get here, it must be a pure specifier for a method.  */
839 	  if (TREE_CODE (TREE_TYPE (value)) == METHOD_TYPE)
840 	    {
841 	      gcc_assert (error_operand_p (init) || integer_zerop (init));
842 	      DECL_PURE_VIRTUAL_P (value) = 1;
843 	    }
844 	  else
845 	    {
846 	      gcc_assert (TREE_CODE (TREE_TYPE (value)) == FUNCTION_TYPE);
847 	      error ("initializer specified for static member function %qD",
848 		     value);
849 	    }
850 	}
851       else if (pedantic && TREE_CODE (value) != VAR_DECL)
852 	/* Already complained in grokdeclarator.  */
853 	init = NULL_TREE;
854       else if (!processing_template_decl)
855 	{
856 	  if (TREE_CODE (init) == CONSTRUCTOR)
857 	    init = digest_init (TREE_TYPE (value), init);
858 	  else
859 	    init = integral_constant_value (init);
860 
861 	  if (init != error_mark_node && !TREE_CONSTANT (init))
862 	    {
863 	      /* We can allow references to things that are effectively
864 		 static, since references are initialized with the
865 		 address.  */
866 	      if (TREE_CODE (TREE_TYPE (value)) != REFERENCE_TYPE
867 		  || (TREE_STATIC (init) == 0
868 		      && (!DECL_P (init) || DECL_EXTERNAL (init) == 0)))
869 		{
870 		  error ("field initializer is not constant");
871 		  init = error_mark_node;
872 		}
873 	    }
874 	}
875     }
876 
877   if (processing_template_decl
878       && (TREE_CODE (value) == VAR_DECL || TREE_CODE (value) == FUNCTION_DECL))
879     {
880       value = push_template_decl (value);
881       if (error_operand_p (value))
882 	return error_mark_node;
883     }
884 
885   if (attrlist)
886     cplus_decl_attributes (&value, attrlist, 0);
887 
888   switch (TREE_CODE (value))
889     {
890     case VAR_DECL:
891       finish_static_data_member_decl (value, init, init_const_expr_p,
892 				      asmspec_tree, flags);
893       return value;
894 
895     case FIELD_DECL:
896       if (asmspec)
897 	error ("%<asm%> specifiers are not permitted on non-static data members");
898       if (DECL_INITIAL (value) == error_mark_node)
899 	init = error_mark_node;
900       cp_finish_decl (value, init, /*init_const_expr_p=*/false,
901 		      NULL_TREE, flags);
902       DECL_INITIAL (value) = init;
903       DECL_IN_AGGR_P (value) = 1;
904       return value;
905 
906     case  FUNCTION_DECL:
907       if (asmspec)
908 	set_user_assembler_name (value, asmspec);
909 
910       cp_finish_decl (value,
911 		      /*init=*/NULL_TREE,
912 		      /*init_const_expr_p=*/false,
913 		      asmspec_tree, flags);
914 
915       /* Pass friends back this way.  */
916       if (DECL_FRIEND_P (value))
917 	return void_type_node;
918 
919       DECL_IN_AGGR_P (value) = 1;
920       return value;
921 
922     default:
923       gcc_unreachable ();
924     }
925   return NULL_TREE;
926 }
927 
928 /* Like `grokfield', but for bitfields.
929    WIDTH is non-NULL for bit fields only, and is an INTEGER_CST node.  */
930 
931 tree
grokbitfield(const cp_declarator * declarator,cp_decl_specifier_seq * declspecs,tree width)932 grokbitfield (const cp_declarator *declarator,
933 	      cp_decl_specifier_seq *declspecs, tree width)
934 {
935   tree value = grokdeclarator (declarator, declspecs, BITFIELD, 0, NULL);
936 
937   if (value == error_mark_node)
938     return NULL_TREE; /* friends went bad.  */
939 
940   /* Pass friendly classes back.  */
941   if (TREE_CODE (value) == VOID_TYPE)
942     return void_type_node;
943 
944   if (!INTEGRAL_TYPE_P (TREE_TYPE (value))
945       && (POINTER_TYPE_P (value)
946           || !dependent_type_p (TREE_TYPE (value))))
947     {
948       error ("bit-field %qD with non-integral type", value);
949       return error_mark_node;
950     }
951 
952   if (TREE_CODE (value) == TYPE_DECL)
953     {
954       error ("cannot declare %qD to be a bit-field type", value);
955       return NULL_TREE;
956     }
957 
958   /* Usually, finish_struct_1 catches bitfields with invalid types.
959      But, in the case of bitfields with function type, we confuse
960      ourselves into thinking they are member functions, so we must
961      check here.  */
962   if (TREE_CODE (value) == FUNCTION_DECL)
963     {
964       error ("cannot declare bit-field %qD with function type",
965 	     DECL_NAME (value));
966       return NULL_TREE;
967     }
968 
969   if (DECL_IN_AGGR_P (value))
970     {
971       error ("%qD is already defined in the class %qT", value,
972 	     DECL_CONTEXT (value));
973       return void_type_node;
974     }
975 
976   if (TREE_STATIC (value))
977     {
978       error ("static member %qD cannot be a bit-field", value);
979       return NULL_TREE;
980     }
981   finish_decl (value, NULL_TREE, NULL_TREE);
982 
983   if (width != error_mark_node)
984     {
985       constant_expression_warning (width);
986       DECL_INITIAL (value) = width;
987       SET_DECL_C_BIT_FIELD (value);
988     }
989 
990   DECL_IN_AGGR_P (value) = 1;
991   return value;
992 }
993 
994 
995 void
cplus_decl_attributes(tree * decl,tree attributes,int flags)996 cplus_decl_attributes (tree *decl, tree attributes, int flags)
997 {
998   if (*decl == NULL_TREE || *decl == void_type_node
999       || *decl == error_mark_node)
1000     return;
1001 
1002   if (TREE_CODE (*decl) == TEMPLATE_DECL)
1003     decl = &DECL_TEMPLATE_RESULT (*decl);
1004 
1005   decl_attributes (decl, attributes, flags);
1006 
1007   if (TREE_CODE (*decl) == TYPE_DECL)
1008     SET_IDENTIFIER_TYPE_VALUE (DECL_NAME (*decl), TREE_TYPE (*decl));
1009 }
1010 
1011 /* Walks through the namespace- or function-scope anonymous union
1012    OBJECT, with the indicated TYPE, building appropriate VAR_DECLs.
1013    Returns one of the fields for use in the mangled name.  */
1014 
1015 static tree
build_anon_union_vars(tree type,tree object)1016 build_anon_union_vars (tree type, tree object)
1017 {
1018   tree main_decl = NULL_TREE;
1019   tree field;
1020 
1021   /* Rather than write the code to handle the non-union case,
1022      just give an error.  */
1023   if (TREE_CODE (type) != UNION_TYPE)
1024     error ("anonymous struct not inside named type");
1025 
1026   for (field = TYPE_FIELDS (type);
1027        field != NULL_TREE;
1028        field = TREE_CHAIN (field))
1029     {
1030       tree decl;
1031       tree ref;
1032 
1033       if (DECL_ARTIFICIAL (field))
1034 	continue;
1035       if (TREE_CODE (field) != FIELD_DECL)
1036 	{
1037 	  pedwarn ("%q+#D invalid; an anonymous union can only "
1038 		   "have non-static data members", field);
1039 	  continue;
1040 	}
1041 
1042       if (TREE_PRIVATE (field))
1043 	pedwarn ("private member %q+#D in anonymous union", field);
1044       else if (TREE_PROTECTED (field))
1045 	pedwarn ("protected member %q+#D in anonymous union", field);
1046 
1047       if (processing_template_decl)
1048 	ref = build_min_nt (COMPONENT_REF, object,
1049 			    DECL_NAME (field), NULL_TREE);
1050       else
1051 	ref = build_class_member_access_expr (object, field, NULL_TREE,
1052 					      false);
1053 
1054       if (DECL_NAME (field))
1055 	{
1056 	  tree base;
1057 
1058 	  decl = build_decl (VAR_DECL, DECL_NAME (field), TREE_TYPE (field));
1059 	  DECL_ANON_UNION_VAR_P (decl) = 1;
1060 
1061 	  base = get_base_address (object);
1062 	  TREE_PUBLIC (decl) = TREE_PUBLIC (base);
1063 	  TREE_STATIC (decl) = TREE_STATIC (base);
1064 	  DECL_EXTERNAL (decl) = DECL_EXTERNAL (base);
1065 
1066 	  SET_DECL_VALUE_EXPR (decl, ref);
1067 	  DECL_HAS_VALUE_EXPR_P (decl) = 1;
1068 
1069 	  decl = pushdecl (decl);
1070 	}
1071       else if (ANON_AGGR_TYPE_P (TREE_TYPE (field)))
1072 	decl = build_anon_union_vars (TREE_TYPE (field), ref);
1073       else
1074 	decl = 0;
1075 
1076       if (main_decl == NULL_TREE)
1077 	main_decl = decl;
1078     }
1079 
1080   return main_decl;
1081 }
1082 
1083 /* Finish off the processing of a UNION_TYPE structure.  If the union is an
1084    anonymous union, then all members must be laid out together.  PUBLIC_P
1085    is nonzero if this union is not declared static.  */
1086 
1087 void
finish_anon_union(tree anon_union_decl)1088 finish_anon_union (tree anon_union_decl)
1089 {
1090   tree type;
1091   tree main_decl;
1092   bool public_p;
1093 
1094   if (anon_union_decl == error_mark_node)
1095     return;
1096 
1097   type = TREE_TYPE (anon_union_decl);
1098   public_p = TREE_PUBLIC (anon_union_decl);
1099 
1100   /* The VAR_DECL's context is the same as the TYPE's context.  */
1101   DECL_CONTEXT (anon_union_decl) = DECL_CONTEXT (TYPE_NAME (type));
1102 
1103   if (TYPE_FIELDS (type) == NULL_TREE)
1104     return;
1105 
1106   if (public_p)
1107     {
1108       error ("namespace-scope anonymous aggregates must be static");
1109       return;
1110     }
1111 
1112   main_decl = build_anon_union_vars (type, anon_union_decl);
1113   if (main_decl == error_mark_node)
1114     return;
1115   if (main_decl == NULL_TREE)
1116     {
1117       warning (0, "anonymous union with no members");
1118       return;
1119     }
1120 
1121   if (!processing_template_decl)
1122     {
1123       /* Use main_decl to set the mangled name.  */
1124       DECL_NAME (anon_union_decl) = DECL_NAME (main_decl);
1125       mangle_decl (anon_union_decl);
1126       DECL_NAME (anon_union_decl) = NULL_TREE;
1127     }
1128 
1129   pushdecl (anon_union_decl);
1130   if (building_stmt_tree ()
1131       && at_function_scope_p ())
1132     add_decl_expr (anon_union_decl);
1133   else if (!processing_template_decl)
1134     rest_of_decl_compilation (anon_union_decl,
1135 			      toplevel_bindings_p (), at_eof);
1136 }
1137 
1138 /* Auxiliary functions to make type signatures for
1139    `operator new' and `operator delete' correspond to
1140    what compiler will be expecting.  */
1141 
1142 tree
coerce_new_type(tree type)1143 coerce_new_type (tree type)
1144 {
1145   int e = 0;
1146   tree args = TYPE_ARG_TYPES (type);
1147 
1148   gcc_assert (TREE_CODE (type) == FUNCTION_TYPE);
1149 
1150   if (!same_type_p (TREE_TYPE (type), ptr_type_node))
1151     {
1152       e = 1;
1153       error ("%<operator new%> must return type %qT", ptr_type_node);
1154     }
1155 
1156   if (!args || args == void_list_node
1157       || !same_type_p (TREE_VALUE (args), size_type_node))
1158     {
1159       e = 2;
1160       if (args && args != void_list_node)
1161 	args = TREE_CHAIN (args);
1162       pedwarn ("%<operator new%> takes type %<size_t%> (%qT) "
1163 	       "as first parameter", size_type_node);
1164     }
1165   switch (e)
1166   {
1167     case 2:
1168       args = tree_cons (NULL_TREE, size_type_node, args);
1169       /* Fall through.  */
1170     case 1:
1171       type = build_exception_variant
1172 	      (build_function_type (ptr_type_node, args),
1173 	       TYPE_RAISES_EXCEPTIONS (type));
1174       /* Fall through.  */
1175     default:;
1176   }
1177   return type;
1178 }
1179 
1180 tree
coerce_delete_type(tree type)1181 coerce_delete_type (tree type)
1182 {
1183   int e = 0;
1184   tree args = TYPE_ARG_TYPES (type);
1185 
1186   gcc_assert (TREE_CODE (type) == FUNCTION_TYPE);
1187 
1188   if (!same_type_p (TREE_TYPE (type), void_type_node))
1189     {
1190       e = 1;
1191       error ("%<operator delete%> must return type %qT", void_type_node);
1192     }
1193 
1194   if (!args || args == void_list_node
1195       || !same_type_p (TREE_VALUE (args), ptr_type_node))
1196     {
1197       e = 2;
1198       if (args && args != void_list_node)
1199 	args = TREE_CHAIN (args);
1200       error ("%<operator delete%> takes type %qT as first parameter",
1201 	     ptr_type_node);
1202     }
1203   switch (e)
1204   {
1205     case 2:
1206       args = tree_cons (NULL_TREE, ptr_type_node, args);
1207       /* Fall through.  */
1208     case 1:
1209       type = build_exception_variant
1210 	      (build_function_type (void_type_node, args),
1211 	       TYPE_RAISES_EXCEPTIONS (type));
1212       /* Fall through.  */
1213     default:;
1214   }
1215 
1216   return type;
1217 }
1218 
1219 static void
mark_vtable_entries(tree decl)1220 mark_vtable_entries (tree decl)
1221 {
1222   tree fnaddr;
1223   unsigned HOST_WIDE_INT idx;
1224 
1225   FOR_EACH_CONSTRUCTOR_VALUE (CONSTRUCTOR_ELTS (DECL_INITIAL (decl)),
1226 			      idx, fnaddr)
1227     {
1228       tree fn;
1229 
1230       STRIP_NOPS (fnaddr);
1231 
1232       if (TREE_CODE (fnaddr) != ADDR_EXPR
1233 	  && TREE_CODE (fnaddr) != FDESC_EXPR)
1234 	/* This entry is an offset: a virtual base class offset, a
1235 	   virtual call offset, an RTTI offset, etc.  */
1236 	continue;
1237 
1238       fn = TREE_OPERAND (fnaddr, 0);
1239       TREE_ADDRESSABLE (fn) = 1;
1240       /* When we don't have vcall offsets, we output thunks whenever
1241 	 we output the vtables that contain them.  With vcall offsets,
1242 	 we know all the thunks we'll need when we emit a virtual
1243 	 function, so we emit the thunks there instead.  */
1244       if (DECL_THUNK_P (fn))
1245 	use_thunk (fn, /*emit_p=*/0);
1246       mark_used (fn);
1247     }
1248 }
1249 
1250 /* Set DECL up to have the closest approximation of "initialized common"
1251    linkage available.  */
1252 
1253 void
comdat_linkage(tree decl)1254 comdat_linkage (tree decl)
1255 {
1256   if (flag_weak)
1257     make_decl_one_only (decl);
1258   else if (TREE_CODE (decl) == FUNCTION_DECL
1259 	   || (TREE_CODE (decl) == VAR_DECL && DECL_ARTIFICIAL (decl)))
1260     /* We can just emit function and compiler-generated variables
1261        statically; having multiple copies is (for the most part) only
1262        a waste of space.
1263 
1264        There are two correctness issues, however: the address of a
1265        template instantiation with external linkage should be the
1266        same, independent of what translation unit asks for the
1267        address, and this will not hold when we emit multiple copies of
1268        the function.  However, there's little else we can do.
1269 
1270        Also, by default, the typeinfo implementation assumes that
1271        there will be only one copy of the string used as the name for
1272        each type.  Therefore, if weak symbols are unavailable, the
1273        run-time library should perform a more conservative check; it
1274        should perform a string comparison, rather than an address
1275        comparison.  */
1276     TREE_PUBLIC (decl) = 0;
1277   else
1278     {
1279       /* Static data member template instantiations, however, cannot
1280 	 have multiple copies.  */
1281       if (DECL_INITIAL (decl) == 0
1282 	  || DECL_INITIAL (decl) == error_mark_node)
1283 	DECL_COMMON (decl) = 1;
1284       else if (EMPTY_CONSTRUCTOR_P (DECL_INITIAL (decl)))
1285 	{
1286 	  DECL_COMMON (decl) = 1;
1287 	  DECL_INITIAL (decl) = error_mark_node;
1288 	}
1289       else if (!DECL_EXPLICIT_INSTANTIATION (decl))
1290 	{
1291 	  /* We can't do anything useful; leave vars for explicit
1292 	     instantiation.  */
1293 	  DECL_EXTERNAL (decl) = 1;
1294 	  DECL_NOT_REALLY_EXTERN (decl) = 0;
1295 	}
1296     }
1297 
1298   if (DECL_LANG_SPECIFIC (decl))
1299     DECL_COMDAT (decl) = 1;
1300 }
1301 
1302 /* For win32 we also want to put explicit instantiations in
1303    linkonce sections, so that they will be merged with implicit
1304    instantiations; otherwise we get duplicate symbol errors.
1305    For Darwin we do not want explicit instantiations to be
1306    linkonce.  */
1307 
1308 void
maybe_make_one_only(tree decl)1309 maybe_make_one_only (tree decl)
1310 {
1311   /* We used to say that this was not necessary on targets that support weak
1312      symbols, because the implicit instantiations will defer to the explicit
1313      one.  However, that's not actually the case in SVR4; a strong definition
1314      after a weak one is an error.  Also, not making explicit
1315      instantiations one_only means that we can end up with two copies of
1316      some template instantiations.  */
1317   if (! flag_weak)
1318     return;
1319 
1320   /* We can't set DECL_COMDAT on functions, or cp_finish_file will think
1321      we can get away with not emitting them if they aren't used.  We need
1322      to for variables so that cp_finish_decl will update their linkage,
1323      because their DECL_INITIAL may not have been set properly yet.  */
1324 
1325   if (!TARGET_WEAK_NOT_IN_ARCHIVE_TOC
1326       || (! DECL_EXPLICIT_INSTANTIATION (decl)
1327 	  && ! DECL_TEMPLATE_SPECIALIZATION (decl)))
1328     {
1329       make_decl_one_only (decl);
1330 
1331       if (TREE_CODE (decl) == VAR_DECL)
1332 	{
1333 	  DECL_COMDAT (decl) = 1;
1334 	  /* Mark it needed so we don't forget to emit it.  */
1335 	  mark_decl_referenced (decl);
1336 	}
1337     }
1338 }
1339 
1340 /* Determine whether or not we want to specifically import or export CTYPE,
1341    using various heuristics.  */
1342 
1343 static void
import_export_class(tree ctype)1344 import_export_class (tree ctype)
1345 {
1346   /* -1 for imported, 1 for exported.  */
1347   int import_export = 0;
1348 
1349   /* It only makes sense to call this function at EOF.  The reason is
1350      that this function looks at whether or not the first non-inline
1351      non-abstract virtual member function has been defined in this
1352      translation unit.  But, we can't possibly know that until we've
1353      seen the entire translation unit.  */
1354   gcc_assert (at_eof);
1355 
1356   if (CLASSTYPE_INTERFACE_KNOWN (ctype))
1357     return;
1358 
1359   /* If MULTIPLE_SYMBOL_SPACES is set and we saw a #pragma interface,
1360      we will have CLASSTYPE_INTERFACE_ONLY set but not
1361      CLASSTYPE_INTERFACE_KNOWN.  In that case, we don't want to use this
1362      heuristic because someone will supply a #pragma implementation
1363      elsewhere, and deducing it here would produce a conflict.  */
1364   if (CLASSTYPE_INTERFACE_ONLY (ctype))
1365     return;
1366 
1367   if (lookup_attribute ("dllimport", TYPE_ATTRIBUTES (ctype)))
1368     import_export = -1;
1369   else if (lookup_attribute ("dllexport", TYPE_ATTRIBUTES (ctype)))
1370     import_export = 1;
1371   else if (CLASSTYPE_IMPLICIT_INSTANTIATION (ctype)
1372 	   && !flag_implicit_templates)
1373     /* For a template class, without -fimplicit-templates, check the
1374        repository.  If the virtual table is assigned to this
1375        translation unit, then export the class; otherwise, import
1376        it.  */
1377       import_export = repo_export_class_p (ctype) ? 1 : -1;
1378   else if (TYPE_POLYMORPHIC_P (ctype))
1379     {
1380       /* The ABI specifies that the virtual table and associated
1381 	 information are emitted with the key method, if any.  */
1382       tree method = CLASSTYPE_KEY_METHOD (ctype);
1383       /* If weak symbol support is not available, then we must be
1384 	 careful not to emit the vtable when the key function is
1385 	 inline.  An inline function can be defined in multiple
1386 	 translation units.  If we were to emit the vtable in each
1387 	 translation unit containing a definition, we would get
1388 	 multiple definition errors at link-time.  */
1389       if (method && (flag_weak || ! DECL_DECLARED_INLINE_P (method)))
1390 	import_export = (DECL_REALLY_EXTERN (method) ? -1 : 1);
1391     }
1392 
1393   /* When MULTIPLE_SYMBOL_SPACES is set, we cannot count on seeing
1394      a definition anywhere else.  */
1395   if (MULTIPLE_SYMBOL_SPACES && import_export == -1)
1396     import_export = 0;
1397 
1398   /* Allow backends the chance to overrule the decision.  */
1399   if (targetm.cxx.import_export_class)
1400     import_export = targetm.cxx.import_export_class (ctype, import_export);
1401 
1402   if (import_export)
1403     {
1404       SET_CLASSTYPE_INTERFACE_KNOWN (ctype);
1405       CLASSTYPE_INTERFACE_ONLY (ctype) = (import_export < 0);
1406     }
1407 }
1408 
1409 /* Return true if VAR has already been provided to the back end; in that
1410    case VAR should not be modified further by the front end.  */
1411 static bool
var_finalized_p(tree var)1412 var_finalized_p (tree var)
1413 {
1414   return cgraph_varpool_node (var)->finalized;
1415 }
1416 
1417 /* DECL is a VAR_DECL or FUNCTION_DECL which, for whatever reason,
1418    must be emitted in this translation unit.  Mark it as such.  */
1419 
1420 void
mark_needed(tree decl)1421 mark_needed (tree decl)
1422 {
1423   /* It's possible that we no longer need to set
1424      TREE_SYMBOL_REFERENCED here directly, but doing so is
1425      harmless.  */
1426   TREE_SYMBOL_REFERENCED (DECL_ASSEMBLER_NAME (decl)) = 1;
1427   mark_decl_referenced (decl);
1428 }
1429 
1430 /* DECL is either a FUNCTION_DECL or a VAR_DECL.  This function
1431    returns true if a definition of this entity should be provided in
1432    this object file.  Callers use this function to determine whether
1433    or not to let the back end know that a definition of DECL is
1434    available in this translation unit.  */
1435 
1436 bool
decl_needed_p(tree decl)1437 decl_needed_p (tree decl)
1438 {
1439   gcc_assert (TREE_CODE (decl) == VAR_DECL
1440 	      || TREE_CODE (decl) == FUNCTION_DECL);
1441   /* This function should only be called at the end of the translation
1442      unit.  We cannot be sure of whether or not something will be
1443      COMDAT until that point.  */
1444   gcc_assert (at_eof);
1445 
1446   /* All entities with external linkage that are not COMDAT should be
1447      emitted; they may be referred to from other object files.  */
1448   if (TREE_PUBLIC (decl) && !DECL_COMDAT (decl))
1449     return true;
1450   /* If this entity was used, let the back-end see it; it will decide
1451      whether or not to emit it into the object file.  */
1452   if (TREE_USED (decl)
1453       || (DECL_ASSEMBLER_NAME_SET_P (decl)
1454 	  && TREE_SYMBOL_REFERENCED (DECL_ASSEMBLER_NAME (decl))))
1455       return true;
1456   /* Otherwise, DECL does not need to be emitted -- yet.  A subsequent
1457      reference to DECL might cause it to be emitted later.  */
1458   return false;
1459 }
1460 
1461 /* If necessary, write out the vtables for the dynamic class CTYPE.
1462    Returns true if any vtables were emitted.  */
1463 
1464 static bool
maybe_emit_vtables(tree ctype)1465 maybe_emit_vtables (tree ctype)
1466 {
1467   tree vtbl;
1468   tree primary_vtbl;
1469   int needed = 0;
1470 
1471   /* If the vtables for this class have already been emitted there is
1472      nothing more to do.  */
1473   primary_vtbl = CLASSTYPE_VTABLES (ctype);
1474   if (var_finalized_p (primary_vtbl))
1475     return false;
1476   /* Ignore dummy vtables made by get_vtable_decl.  */
1477   if (TREE_TYPE (primary_vtbl) == void_type_node)
1478     return false;
1479 
1480   /* On some targets, we cannot determine the key method until the end
1481      of the translation unit -- which is when this function is
1482      called.  */
1483   if (!targetm.cxx.key_method_may_be_inline ())
1484     determine_key_method (ctype);
1485 
1486   /* See if any of the vtables are needed.  */
1487   for (vtbl = CLASSTYPE_VTABLES (ctype); vtbl; vtbl = TREE_CHAIN (vtbl))
1488     {
1489       import_export_decl (vtbl);
1490       if (DECL_NOT_REALLY_EXTERN (vtbl) && decl_needed_p (vtbl))
1491 	needed = 1;
1492     }
1493   if (!needed)
1494     {
1495       /* If the references to this class' vtables are optimized away,
1496 	 still emit the appropriate debugging information.  See
1497 	 dfs_debug_mark.  */
1498       if (DECL_COMDAT (primary_vtbl)
1499 	  && CLASSTYPE_DEBUG_REQUESTED (ctype))
1500 	note_debug_info_needed (ctype);
1501       return false;
1502     }
1503 
1504   /* The ABI requires that we emit all of the vtables if we emit any
1505      of them.  */
1506   for (vtbl = CLASSTYPE_VTABLES (ctype); vtbl; vtbl = TREE_CHAIN (vtbl))
1507     {
1508       /* Mark entities references from the virtual table as used.  */
1509       mark_vtable_entries (vtbl);
1510 
1511       if (TREE_TYPE (DECL_INITIAL (vtbl)) == 0)
1512 	{
1513 	  tree expr = store_init_value (vtbl, DECL_INITIAL (vtbl));
1514 
1515 	  /* It had better be all done at compile-time.  */
1516 	  gcc_assert (!expr);
1517 	}
1518 
1519       /* Write it out.  */
1520       DECL_EXTERNAL (vtbl) = 0;
1521       rest_of_decl_compilation (vtbl, 1, 1);
1522 
1523       /* Because we're only doing syntax-checking, we'll never end up
1524 	 actually marking the variable as written.  */
1525       if (flag_syntax_only)
1526 	TREE_ASM_WRITTEN (vtbl) = 1;
1527     }
1528 
1529   /* Since we're writing out the vtable here, also write the debug
1530      info.  */
1531   note_debug_info_needed (ctype);
1532 
1533   return true;
1534 }
1535 
1536 /* A special return value from type_visibility meaning internal
1537    linkage.  */
1538 
1539 enum { VISIBILITY_ANON = VISIBILITY_INTERNAL+1 };
1540 
1541 /* walk_tree helper function for type_visibility.  */
1542 
1543 static tree
min_vis_r(tree * tp,int * walk_subtrees,void * data)1544 min_vis_r (tree *tp, int *walk_subtrees, void *data)
1545 {
1546   int *vis_p = (int *)data;
1547   if (! TYPE_P (*tp))
1548     {
1549       *walk_subtrees = 0;
1550     }
1551   else if (CLASS_TYPE_P (*tp))
1552     {
1553       if (!TREE_PUBLIC (TYPE_MAIN_DECL (*tp)))
1554 	{
1555 	  *vis_p = VISIBILITY_ANON;
1556 	  return *tp;
1557 	}
1558       else if (CLASSTYPE_VISIBILITY (*tp) > *vis_p)
1559 	*vis_p = CLASSTYPE_VISIBILITY (*tp);
1560     }
1561   return NULL;
1562 }
1563 
1564 /* Returns the visibility of TYPE, which is the minimum visibility of its
1565    component types.  */
1566 
1567 static int
type_visibility(tree type)1568 type_visibility (tree type)
1569 {
1570   int vis = VISIBILITY_DEFAULT;
1571   walk_tree_without_duplicates (&type, min_vis_r, &vis);
1572   return vis;
1573 }
1574 
1575 /* Limit the visibility of DECL to VISIBILITY, if not explicitly
1576    specified (or if VISIBILITY is static).  */
1577 
1578 static bool
constrain_visibility(tree decl,int visibility)1579 constrain_visibility (tree decl, int visibility)
1580 {
1581   if (visibility == VISIBILITY_ANON)
1582     {
1583       /* extern "C" declarations aren't affected by the anonymous
1584 	 namespace.  */
1585       if (!DECL_EXTERN_C_P (decl))
1586 	{
1587 	  TREE_PUBLIC (decl) = 0;
1588 	  DECL_INTERFACE_KNOWN (decl) = 1;
1589 	  if (DECL_LANG_SPECIFIC (decl))
1590 	    DECL_NOT_REALLY_EXTERN (decl) = 1;
1591 	}
1592     }
1593   else if (visibility > DECL_VISIBILITY (decl)
1594 	   && !DECL_VISIBILITY_SPECIFIED (decl))
1595     {
1596       DECL_VISIBILITY (decl) = visibility;
1597       return true;
1598     }
1599   return false;
1600 }
1601 
1602 /* Constrain the visibility of DECL based on the visibility of its template
1603    arguments.  */
1604 
1605 static void
constrain_visibility_for_template(tree decl,tree targs)1606 constrain_visibility_for_template (tree decl, tree targs)
1607 {
1608   /* If this is a template instantiation, check the innermost
1609      template args for visibility constraints.  The outer template
1610      args are covered by the class check.  */
1611   tree args = INNERMOST_TEMPLATE_ARGS (targs);
1612   int i;
1613   for (i = TREE_VEC_LENGTH (args); i > 0; --i)
1614     {
1615       int vis = 0;
1616 
1617       tree arg = TREE_VEC_ELT (args, i-1);
1618       if (TYPE_P (arg))
1619 	vis = type_visibility (arg);
1620       else if (TREE_TYPE (arg) && POINTER_TYPE_P (TREE_TYPE (arg)))
1621 	{
1622 	  STRIP_NOPS (arg);
1623 	  if (TREE_CODE (arg) == ADDR_EXPR)
1624 	    arg = TREE_OPERAND (arg, 0);
1625 	  if (TREE_CODE (arg) == VAR_DECL
1626 	      || TREE_CODE (arg) == FUNCTION_DECL)
1627 	    {
1628 	      if (! TREE_PUBLIC (arg))
1629 		vis = VISIBILITY_ANON;
1630 	      else
1631 		vis = DECL_VISIBILITY (arg);
1632 	    }
1633 	}
1634       if (vis)
1635 	constrain_visibility (decl, vis);
1636     }
1637 }
1638 
1639 /* Like c_determine_visibility, but with additional C++-specific
1640    behavior.
1641 
1642    Function-scope entities can rely on the function's visibility because
1643    it is set in start_preparsed_function.
1644 
1645    Class-scope entities cannot rely on the class's visibility until the end
1646    of the enclosing class definition.
1647 
1648    Note that because namespaces have multiple independent definitions,
1649    namespace visibility is handled elsewhere using the #pragma visibility
1650    machinery rather than by decorating the namespace declaration.
1651 
1652    The goal is for constraints from the type to give a diagnostic, and
1653    other constraints to be applied silently.  */
1654 
1655 void
determine_visibility(tree decl)1656 determine_visibility (tree decl)
1657 {
1658   tree class_type = NULL_TREE;
1659   bool use_template;
1660 
1661   /* Remember that all decls get VISIBILITY_DEFAULT when built.  */
1662 
1663   /* Only relevant for names with external linkage.  */
1664   if (!TREE_PUBLIC (decl))
1665     return;
1666 
1667   /* Cloned constructors and destructors get the same visibility as
1668      the underlying function.  That should be set up in
1669      maybe_clone_body.  */
1670   gcc_assert (!DECL_CLONED_FUNCTION_P (decl));
1671 
1672   if (TREE_CODE (decl) == TYPE_DECL)
1673     {
1674       if (CLASS_TYPE_P (TREE_TYPE (decl)))
1675 	use_template = CLASSTYPE_USE_TEMPLATE (TREE_TYPE (decl));
1676       else if (TYPE_TEMPLATE_INFO (TREE_TYPE (decl)))
1677 	use_template = 1;
1678       else
1679 	use_template = 0;
1680     }
1681   else if (DECL_LANG_SPECIFIC (decl))
1682     use_template = DECL_USE_TEMPLATE (decl);
1683   else
1684     use_template = 0;
1685 
1686   /* Anything that is exported must have default visibility.  */
1687   if (TARGET_DLLIMPORT_DECL_ATTRIBUTES
1688       && lookup_attribute ("dllexport",
1689 			   TREE_CODE (decl) == TYPE_DECL
1690 			   ? TYPE_ATTRIBUTES (TREE_TYPE (decl))
1691 			   : DECL_ATTRIBUTES (decl)))
1692     {
1693       DECL_VISIBILITY (decl) = VISIBILITY_DEFAULT;
1694       DECL_VISIBILITY_SPECIFIED (decl) = 1;
1695     }
1696 
1697   /* If DECL is a member of a class, visibility specifiers on the
1698      class can influence the visibility of the DECL.  */
1699   if (DECL_CLASS_SCOPE_P (decl))
1700     class_type = DECL_CONTEXT (decl);
1701   else if (TREE_CODE (decl) == VAR_DECL
1702 	   && DECL_TINFO_P (decl)
1703 	   && CLASS_TYPE_P (TREE_TYPE (DECL_NAME (decl))))
1704     class_type = TREE_TYPE (DECL_NAME (decl));
1705   else
1706     {
1707       /* Not a class member.  */
1708 
1709       /* Virtual tables have DECL_CONTEXT set to their associated class,
1710 	 so they are automatically handled above.  */
1711       gcc_assert (TREE_CODE (decl) != VAR_DECL
1712 		  || !DECL_VTABLE_OR_VTT_P (decl));
1713 
1714       if (DECL_FUNCTION_SCOPE_P (decl) && ! DECL_VISIBILITY_SPECIFIED (decl))
1715 	{
1716 	  /* Local statics and classes get the visibility of their
1717 	     containing function by default, except that
1718 	     -fvisibility-inlines-hidden doesn't affect them.  */
1719 	  tree fn = DECL_CONTEXT (decl);
1720 	  if (DECL_VISIBILITY_SPECIFIED (fn) || ! DECL_CLASS_SCOPE_P (fn))
1721 	    {
1722 	      DECL_VISIBILITY (decl) = DECL_VISIBILITY (fn);
1723 	      DECL_VISIBILITY_SPECIFIED (decl) =
1724 		DECL_VISIBILITY_SPECIFIED (fn);
1725 	    }
1726 	  else
1727 	    determine_visibility_from_class (decl, DECL_CONTEXT (fn));
1728 
1729 	  /* Local classes in templates have CLASSTYPE_USE_TEMPLATE set,
1730 	     but have no TEMPLATE_INFO, so don't try to check it.  */
1731 	  use_template = 0;
1732 	}
1733       else if (TREE_CODE (decl) == VAR_DECL && DECL_TINFO_P (decl))
1734 	{
1735 	  /* tinfo visibility is based on the type it's for.  */
1736 	  constrain_visibility
1737 	    (decl, type_visibility (TREE_TYPE (DECL_NAME (decl))));
1738 	}
1739       else if (use_template)
1740 	/* Template instantiations and specializations get visibility based
1741 	   on their template unless they override it with an attribute.  */;
1742       else if (! DECL_VISIBILITY_SPECIFIED (decl))
1743 	{
1744 	  /* Set default visibility to whatever the user supplied with
1745 	     #pragma GCC visibility or a namespace visibility attribute.  */
1746 	  DECL_VISIBILITY (decl) = default_visibility;
1747 	  DECL_VISIBILITY_SPECIFIED (decl) = visibility_options.inpragma;
1748 	}
1749     }
1750 
1751   if (use_template)
1752     {
1753       /* If the specialization doesn't specify visibility, use the
1754 	 visibility from the template.  */
1755       tree tinfo = (TREE_CODE (decl) == TYPE_DECL
1756 		    ? TYPE_TEMPLATE_INFO (TREE_TYPE (decl))
1757 		    : DECL_TEMPLATE_INFO (decl));
1758       tree args = TI_ARGS (tinfo);
1759 
1760       if (args != error_mark_node)
1761 	{
1762 	  int depth = TMPL_ARGS_DEPTH (args);
1763 	  tree pattern = DECL_TEMPLATE_RESULT (TI_TEMPLATE (tinfo));
1764 
1765 	  if (!DECL_VISIBILITY_SPECIFIED (decl))
1766 	    {
1767 	      DECL_VISIBILITY (decl) = DECL_VISIBILITY (pattern);
1768 	      DECL_VISIBILITY_SPECIFIED (decl)
1769 		= DECL_VISIBILITY_SPECIFIED (pattern);
1770 	    }
1771 
1772 	  /* FIXME should TMPL_ARGS_DEPTH really return 1 for null input? */
1773 	  if (args && depth > template_class_depth (class_type))
1774 	    /* Limit visibility based on its template arguments.  */
1775 	    constrain_visibility_for_template (decl, args);
1776 	}
1777     }
1778 
1779   if (class_type)
1780     determine_visibility_from_class (decl, class_type);
1781 
1782   if (decl_anon_ns_mem_p (decl))
1783     /* Names in an anonymous namespace get internal linkage.
1784        This might change once we implement export.  */
1785     constrain_visibility (decl, VISIBILITY_ANON);
1786   else if (TREE_CODE (decl) != TYPE_DECL)
1787     {
1788       /* Propagate anonymity from type to decl.  */
1789       int tvis = type_visibility (TREE_TYPE (decl));
1790       if (tvis == VISIBILITY_ANON)
1791 	constrain_visibility (decl, tvis);
1792     }
1793 }
1794 
1795 /* By default, static data members and function members receive
1796    the visibility of their containing class.  */
1797 
1798 static void
determine_visibility_from_class(tree decl,tree class_type)1799 determine_visibility_from_class (tree decl, tree class_type)
1800 {
1801   if (visibility_options.inlines_hidden
1802       /* Don't do this for inline templates; specializations might not be
1803 	 inline, and we don't want them to inherit the hidden
1804 	 visibility.  We'll set it here for all inline instantiations.  */
1805       && !processing_template_decl
1806       && ! DECL_VISIBILITY_SPECIFIED (decl)
1807       && TREE_CODE (decl) == FUNCTION_DECL
1808       && DECL_DECLARED_INLINE_P (decl)
1809       && (! DECL_LANG_SPECIFIC (decl)
1810 	  || ! DECL_EXPLICIT_INSTANTIATION (decl)))
1811     DECL_VISIBILITY (decl) = VISIBILITY_HIDDEN;
1812   else if (!DECL_VISIBILITY_SPECIFIED (decl))
1813     {
1814       /* Default to the class visibility.  */
1815       DECL_VISIBILITY (decl) = CLASSTYPE_VISIBILITY (class_type);
1816       DECL_VISIBILITY_SPECIFIED (decl)
1817 	= CLASSTYPE_VISIBILITY_SPECIFIED (class_type);
1818     }
1819 
1820   /* Give the target a chance to override the visibility associated
1821      with DECL.  */
1822   if (TREE_CODE (decl) == VAR_DECL
1823       && (DECL_TINFO_P (decl)
1824 	  || (DECL_VTABLE_OR_VTT_P (decl)
1825 	      /* Construction virtual tables are not exported because
1826 		 they cannot be referred to from other object files;
1827 		 their name is not standardized by the ABI.  */
1828 	      && !DECL_CONSTRUCTION_VTABLE_P (decl)))
1829       && TREE_PUBLIC (decl)
1830       && !DECL_REALLY_EXTERN (decl)
1831       && !DECL_VISIBILITY_SPECIFIED (decl)
1832       && !CLASSTYPE_VISIBILITY_SPECIFIED (class_type))
1833     targetm.cxx.determine_class_data_visibility (decl);
1834 }
1835 
1836 /* Constrain the visibility of a class TYPE based on the visibility of its
1837    field types.  Warn if any fields require lesser visibility.  */
1838 
1839 void
constrain_class_visibility(tree type)1840 constrain_class_visibility (tree type)
1841 {
1842   tree binfo;
1843   tree t;
1844   int i;
1845 
1846   int vis = type_visibility (type);
1847 
1848   if (vis == VISIBILITY_ANON
1849       || DECL_IN_SYSTEM_HEADER (TYPE_MAIN_DECL (type)))
1850     return;
1851 
1852   /* Don't warn about visibility if the class has explicit visibility.  */
1853   if (CLASSTYPE_VISIBILITY_SPECIFIED (type))
1854     vis = VISIBILITY_INTERNAL;
1855 
1856   for (t = TYPE_FIELDS (type); t; t = TREE_CHAIN (t))
1857     if (TREE_CODE (t) == FIELD_DECL && TREE_TYPE (t) != error_mark_node)
1858       {
1859 	tree ftype = strip_array_types (TREE_TYPE (t));
1860 	int subvis = type_visibility (ftype);
1861 
1862 	if (subvis == VISIBILITY_ANON)
1863 	  warning (0, "\
1864 %qT has a field %qD whose type uses the anonymous namespace",
1865 		   type, t);
1866 	else if (IS_AGGR_TYPE (ftype)
1867 		 && vis < VISIBILITY_HIDDEN
1868 		 && subvis >= VISIBILITY_HIDDEN)
1869 	  warning (OPT_Wattributes, "\
1870 %qT declared with greater visibility than the type of its field %qD",
1871 		   type, t);
1872       }
1873 
1874   binfo = TYPE_BINFO (type);
1875   for (i = 0; BINFO_BASE_ITERATE (binfo, i, t); ++i)
1876     {
1877       int subvis = type_visibility (TREE_TYPE (t));
1878 
1879       if (subvis == VISIBILITY_ANON)
1880 	warning (0, "\
1881 %qT has a base %qT whose type uses the anonymous namespace",
1882 		 type, TREE_TYPE (t));
1883       else if (vis < VISIBILITY_HIDDEN
1884 	       && subvis >= VISIBILITY_HIDDEN)
1885 	warning (OPT_Wattributes, "\
1886 %qT declared with greater visibility than its base %qT",
1887 		 type, TREE_TYPE (t));
1888     }
1889 }
1890 
1891 /* DECL is a FUNCTION_DECL or VAR_DECL.  If the object file linkage
1892    for DECL has not already been determined, do so now by setting
1893    DECL_EXTERNAL, DECL_COMDAT and other related flags.  Until this
1894    function is called entities with vague linkage whose definitions
1895    are available must have TREE_PUBLIC set.
1896 
1897    If this function decides to place DECL in COMDAT, it will set
1898    appropriate flags -- but will not clear DECL_EXTERNAL.  It is up to
1899    the caller to decide whether or not to clear DECL_EXTERNAL.  Some
1900    callers defer that decision until it is clear that DECL is actually
1901    required.  */
1902 
1903 void
import_export_decl(tree decl)1904 import_export_decl (tree decl)
1905 {
1906   int emit_p;
1907   bool comdat_p;
1908   bool import_p;
1909   tree class_type = NULL_TREE;
1910 
1911   if (DECL_INTERFACE_KNOWN (decl))
1912     return;
1913 
1914   /* We cannot determine what linkage to give to an entity with vague
1915      linkage until the end of the file.  For example, a virtual table
1916      for a class will be defined if and only if the key method is
1917      defined in this translation unit.  As a further example, consider
1918      that when compiling a translation unit that uses PCH file with
1919      "-frepo" it would be incorrect to make decisions about what
1920      entities to emit when building the PCH; those decisions must be
1921      delayed until the repository information has been processed.  */
1922   gcc_assert (at_eof);
1923   /* Object file linkage for explicit instantiations is handled in
1924      mark_decl_instantiated.  For static variables in functions with
1925      vague linkage, maybe_commonize_var is used.
1926 
1927      Therefore, the only declarations that should be provided to this
1928      function are those with external linkage that are:
1929 
1930      * implicit instantiations of function templates
1931 
1932      * inline function
1933 
1934      * implicit instantiations of static data members of class
1935        templates
1936 
1937      * virtual tables
1938 
1939      * typeinfo objects
1940 
1941      Furthermore, all entities that reach this point must have a
1942      definition available in this translation unit.
1943 
1944      The following assertions check these conditions.  */
1945   gcc_assert (TREE_CODE (decl) == FUNCTION_DECL
1946 	      || TREE_CODE (decl) == VAR_DECL);
1947   /* Any code that creates entities with TREE_PUBLIC cleared should
1948      also set DECL_INTERFACE_KNOWN.  */
1949   gcc_assert (TREE_PUBLIC (decl));
1950   if (TREE_CODE (decl) == FUNCTION_DECL)
1951     gcc_assert (DECL_IMPLICIT_INSTANTIATION (decl)
1952 		|| DECL_FRIEND_PSEUDO_TEMPLATE_INSTANTIATION (decl)
1953 		|| DECL_DECLARED_INLINE_P (decl));
1954   else
1955     gcc_assert (DECL_IMPLICIT_INSTANTIATION (decl)
1956 		|| DECL_VTABLE_OR_VTT_P (decl)
1957 		|| DECL_TINFO_P (decl));
1958   /* Check that a definition of DECL is available in this translation
1959      unit.  */
1960   gcc_assert (!DECL_REALLY_EXTERN (decl));
1961 
1962   /* Assume that DECL will not have COMDAT linkage.  */
1963   comdat_p = false;
1964   /* Assume that DECL will not be imported into this translation
1965      unit.  */
1966   import_p = false;
1967 
1968   /* See if the repository tells us whether or not to emit DECL in
1969      this translation unit.  */
1970   emit_p = repo_emit_p (decl);
1971   if (emit_p == 0)
1972     import_p = true;
1973   else if (emit_p == 1)
1974     {
1975       /* The repository indicates that this entity should be defined
1976 	 here.  Make sure the back end honors that request.  */
1977       if (TREE_CODE (decl) == VAR_DECL)
1978 	mark_needed (decl);
1979       else if (DECL_MAYBE_IN_CHARGE_CONSTRUCTOR_P (decl)
1980 	       || DECL_MAYBE_IN_CHARGE_DESTRUCTOR_P (decl))
1981 	{
1982 	  tree clone;
1983 	  FOR_EACH_CLONE (clone, decl)
1984 	    mark_needed (clone);
1985 	}
1986       else
1987 	mark_needed (decl);
1988       /* Output the definition as an ordinary strong definition.  */
1989       DECL_EXTERNAL (decl) = 0;
1990       DECL_INTERFACE_KNOWN (decl) = 1;
1991       return;
1992     }
1993 
1994   if (import_p)
1995     /* We have already decided what to do with this DECL; there is no
1996        need to check anything further.  */
1997     ;
1998   else if (TREE_CODE (decl) == VAR_DECL && DECL_VTABLE_OR_VTT_P (decl))
1999     {
2000       class_type = DECL_CONTEXT (decl);
2001       import_export_class (class_type);
2002       if (TYPE_FOR_JAVA (class_type))
2003 	import_p = true;
2004       else if (CLASSTYPE_INTERFACE_KNOWN (class_type)
2005 	       && CLASSTYPE_INTERFACE_ONLY (class_type))
2006 	import_p = true;
2007       else if ((!flag_weak || TARGET_WEAK_NOT_IN_ARCHIVE_TOC)
2008 	       && !CLASSTYPE_USE_TEMPLATE (class_type)
2009 	       && CLASSTYPE_KEY_METHOD (class_type)
2010 	       && !DECL_DECLARED_INLINE_P (CLASSTYPE_KEY_METHOD (class_type)))
2011 	/* The ABI requires that all virtual tables be emitted with
2012 	   COMDAT linkage.  However, on systems where COMDAT symbols
2013 	   don't show up in the table of contents for a static
2014 	   archive, or on systems without weak symbols (where we
2015 	   approximate COMDAT linkage by using internal linkage), the
2016 	   linker will report errors about undefined symbols because
2017 	   it will not see the virtual table definition.  Therefore,
2018 	   in the case that we know that the virtual table will be
2019 	   emitted in only one translation unit, we make the virtual
2020 	   table an ordinary definition with external linkage.  */
2021 	DECL_EXTERNAL (decl) = 0;
2022       else if (CLASSTYPE_INTERFACE_KNOWN (class_type))
2023 	{
2024 	  /* CLASS_TYPE is being exported from this translation unit,
2025 	     so DECL should be defined here.  */
2026 	  if (!flag_weak && CLASSTYPE_EXPLICIT_INSTANTIATION (class_type))
2027 	    /* If a class is declared in a header with the "extern
2028 	       template" extension, then it will not be instantiated,
2029 	       even in translation units that would normally require
2030 	       it.  Often such classes are explicitly instantiated in
2031 	       one translation unit.  Therefore, the explicit
2032 	       instantiation must be made visible to other translation
2033 	       units.  */
2034 	    DECL_EXTERNAL (decl) = 0;
2035 	  else
2036 	    {
2037 	      /* The generic C++ ABI says that class data is always
2038 		 COMDAT, even if there is a key function.  Some
2039 		 variants (e.g., the ARM EABI) says that class data
2040 		 only has COMDAT linkage if the class data might be
2041 		 emitted in more than one translation unit.  When the
2042 		 key method can be inline and is inline, we still have
2043 		 to arrange for comdat even though
2044 		 class_data_always_comdat is false.  */
2045 	      if (!CLASSTYPE_KEY_METHOD (class_type)
2046 		  || DECL_DECLARED_INLINE_P (CLASSTYPE_KEY_METHOD (class_type))
2047 		  || targetm.cxx.class_data_always_comdat ())
2048 		{
2049 		  /* The ABI requires COMDAT linkage.  Normally, we
2050 		     only emit COMDAT things when they are needed;
2051 		     make sure that we realize that this entity is
2052 		     indeed needed.  */
2053 		  comdat_p = true;
2054 		  mark_needed (decl);
2055 		}
2056 	    }
2057 	}
2058       else if (!flag_implicit_templates
2059 	       && CLASSTYPE_IMPLICIT_INSTANTIATION (class_type))
2060 	import_p = true;
2061       else
2062 	comdat_p = true;
2063     }
2064   else if (TREE_CODE (decl) == VAR_DECL && DECL_TINFO_P (decl))
2065     {
2066       tree type = TREE_TYPE (DECL_NAME (decl));
2067       if (CLASS_TYPE_P (type))
2068 	{
2069 	  class_type = type;
2070 	  import_export_class (type);
2071 	  if (CLASSTYPE_INTERFACE_KNOWN (type)
2072 	      && TYPE_POLYMORPHIC_P (type)
2073 	      && CLASSTYPE_INTERFACE_ONLY (type)
2074 	      /* If -fno-rtti was specified, then we cannot be sure
2075 		 that RTTI information will be emitted with the
2076 		 virtual table of the class, so we must emit it
2077 		 wherever it is used.  */
2078 	      && flag_rtti)
2079 	    import_p = true;
2080 	  else
2081 	    {
2082 	      if (CLASSTYPE_INTERFACE_KNOWN (type)
2083 		  && !CLASSTYPE_INTERFACE_ONLY (type))
2084 		{
2085 		  comdat_p = (targetm.cxx.class_data_always_comdat ()
2086 			      || (CLASSTYPE_KEY_METHOD (type)
2087 				  && DECL_DECLARED_INLINE_P (CLASSTYPE_KEY_METHOD (type))));
2088 		  mark_needed (decl);
2089 		  if (!flag_weak)
2090 		    {
2091 		      comdat_p = false;
2092 		      DECL_EXTERNAL (decl) = 0;
2093 		    }
2094 		}
2095 	      else
2096 		comdat_p = true;
2097 	    }
2098 	}
2099       else
2100 	comdat_p = true;
2101     }
2102   else if (DECL_TEMPLATE_INSTANTIATION (decl)
2103 	   || DECL_FRIEND_PSEUDO_TEMPLATE_INSTANTIATION (decl))
2104     {
2105       /* DECL is an implicit instantiation of a function or static
2106 	 data member.  */
2107       if (flag_implicit_templates
2108 	  || (flag_implicit_inline_templates
2109 	      && TREE_CODE (decl) == FUNCTION_DECL
2110 	      && DECL_DECLARED_INLINE_P (decl)))
2111 	comdat_p = true;
2112       else
2113 	/* If we are not implicitly generating templates, then mark
2114 	   this entity as undefined in this translation unit.  */
2115 	import_p = true;
2116     }
2117   else if (DECL_FUNCTION_MEMBER_P (decl))
2118     {
2119       if (!DECL_DECLARED_INLINE_P (decl))
2120 	{
2121 	  tree ctype = DECL_CONTEXT (decl);
2122 	  import_export_class (ctype);
2123 	  if (CLASSTYPE_INTERFACE_KNOWN (ctype))
2124 	    {
2125 	      DECL_NOT_REALLY_EXTERN (decl)
2126 		= ! (CLASSTYPE_INTERFACE_ONLY (ctype)
2127 		     || (DECL_DECLARED_INLINE_P (decl)
2128 			 && ! flag_implement_inlines
2129 			 && !DECL_VINDEX (decl)));
2130 
2131 	      if (!DECL_NOT_REALLY_EXTERN (decl))
2132 		DECL_EXTERNAL (decl) = 1;
2133 
2134 	      /* Always make artificials weak.  */
2135 	      if (DECL_ARTIFICIAL (decl) && flag_weak)
2136 		comdat_p = true;
2137 	      else
2138 		maybe_make_one_only (decl);
2139 	    }
2140 	}
2141       else
2142 	comdat_p = true;
2143     }
2144   else
2145     comdat_p = true;
2146 
2147   if (import_p)
2148     {
2149       /* If we are importing DECL into this translation unit, mark is
2150 	 an undefined here.  */
2151       DECL_EXTERNAL (decl) = 1;
2152       DECL_NOT_REALLY_EXTERN (decl) = 0;
2153     }
2154   else if (comdat_p)
2155     {
2156       /* If we decided to put DECL in COMDAT, mark it accordingly at
2157 	 this point.  */
2158       comdat_linkage (decl);
2159     }
2160 
2161   DECL_INTERFACE_KNOWN (decl) = 1;
2162 }
2163 
2164 /* Return an expression that performs the destruction of DECL, which
2165    must be a VAR_DECL whose type has a non-trivial destructor, or is
2166    an array whose (innermost) elements have a non-trivial destructor.  */
2167 
2168 tree
build_cleanup(tree decl)2169 build_cleanup (tree decl)
2170 {
2171   tree temp;
2172   tree type = TREE_TYPE (decl);
2173 
2174   /* This function should only be called for declarations that really
2175      require cleanups.  */
2176   gcc_assert (!TYPE_HAS_TRIVIAL_DESTRUCTOR (type));
2177 
2178   /* Treat all objects with destructors as used; the destructor may do
2179      something substantive.  */
2180   mark_used (decl);
2181 
2182   if (TREE_CODE (type) == ARRAY_TYPE)
2183     temp = decl;
2184   else
2185     {
2186       cxx_mark_addressable (decl);
2187       temp = build1 (ADDR_EXPR, build_pointer_type (type), decl);
2188     }
2189   temp = build_delete (TREE_TYPE (temp), temp,
2190 		       sfk_complete_destructor,
2191 		       LOOKUP_NORMAL|LOOKUP_NONVIRTUAL|LOOKUP_DESTRUCTOR, 0);
2192   return temp;
2193 }
2194 
2195 /* Returns the initialization guard variable for the variable DECL,
2196    which has static storage duration.  */
2197 
2198 tree
get_guard(tree decl)2199 get_guard (tree decl)
2200 {
2201   tree sname;
2202   tree guard;
2203 
2204   sname = mangle_guard_variable (decl);
2205   guard = IDENTIFIER_GLOBAL_VALUE (sname);
2206   if (! guard)
2207     {
2208       tree guard_type;
2209 
2210       /* We use a type that is big enough to contain a mutex as well
2211 	 as an integer counter.  */
2212       guard_type = targetm.cxx.guard_type ();
2213       guard = build_decl (VAR_DECL, sname, guard_type);
2214 
2215       /* The guard should have the same linkage as what it guards.  */
2216       TREE_PUBLIC (guard) = TREE_PUBLIC (decl);
2217       TREE_STATIC (guard) = TREE_STATIC (decl);
2218       DECL_COMMON (guard) = DECL_COMMON (decl);
2219       DECL_ONE_ONLY (guard) = DECL_ONE_ONLY (decl);
2220       if (TREE_PUBLIC (decl))
2221 	DECL_WEAK (guard) = DECL_WEAK (decl);
2222 
2223       DECL_ARTIFICIAL (guard) = 1;
2224       DECL_IGNORED_P (guard) = 1;
2225       TREE_USED (guard) = 1;
2226       pushdecl_top_level_and_finish (guard, NULL_TREE);
2227     }
2228   return guard;
2229 }
2230 
2231 /* Return those bits of the GUARD variable that should be set when the
2232    guarded entity is actually initialized.  */
2233 
2234 static tree
get_guard_bits(tree guard)2235 get_guard_bits (tree guard)
2236 {
2237   if (!targetm.cxx.guard_mask_bit ())
2238     {
2239       /* We only set the first byte of the guard, in order to leave room
2240 	 for a mutex in the high-order bits.  */
2241       guard = build1 (ADDR_EXPR,
2242 		      build_pointer_type (TREE_TYPE (guard)),
2243 		      guard);
2244       guard = build1 (NOP_EXPR,
2245 		      build_pointer_type (char_type_node),
2246 		      guard);
2247       guard = build1 (INDIRECT_REF, char_type_node, guard);
2248     }
2249 
2250   return guard;
2251 }
2252 
2253 /* Return an expression which determines whether or not the GUARD
2254    variable has already been initialized.  */
2255 
2256 tree
get_guard_cond(tree guard)2257 get_guard_cond (tree guard)
2258 {
2259   tree guard_value;
2260 
2261   /* Check to see if the GUARD is zero.  */
2262   guard = get_guard_bits (guard);
2263 
2264   /* Mask off all but the low bit.  */
2265   if (targetm.cxx.guard_mask_bit ())
2266     {
2267       guard_value = integer_one_node;
2268       if (!same_type_p (TREE_TYPE (guard_value), TREE_TYPE (guard)))
2269 	guard_value = convert (TREE_TYPE (guard), guard_value);
2270 	guard = cp_build_binary_op (BIT_AND_EXPR, guard, guard_value);
2271     }
2272 
2273   guard_value = integer_zero_node;
2274   if (!same_type_p (TREE_TYPE (guard_value), TREE_TYPE (guard)))
2275     guard_value = convert (TREE_TYPE (guard), guard_value);
2276   return cp_build_binary_op (EQ_EXPR, guard, guard_value);
2277 }
2278 
2279 /* Return an expression which sets the GUARD variable, indicating that
2280    the variable being guarded has been initialized.  */
2281 
2282 tree
set_guard(tree guard)2283 set_guard (tree guard)
2284 {
2285   tree guard_init;
2286 
2287   /* Set the GUARD to one.  */
2288   guard = get_guard_bits (guard);
2289   guard_init = integer_one_node;
2290   if (!same_type_p (TREE_TYPE (guard_init), TREE_TYPE (guard)))
2291     guard_init = convert (TREE_TYPE (guard), guard_init);
2292   return build_modify_expr (guard, NOP_EXPR, guard_init);
2293 }
2294 
2295 /* Start the process of running a particular set of global constructors
2296    or destructors.  Subroutine of do_[cd]tors.  */
2297 
2298 static tree
start_objects(int method_type,int initp)2299 start_objects (int method_type, int initp)
2300 {
2301   tree body;
2302   tree fndecl;
2303   char type[10];
2304 
2305   /* Make ctor or dtor function.  METHOD_TYPE may be 'I' or 'D'.  */
2306 
2307   if (initp != DEFAULT_INIT_PRIORITY)
2308     {
2309       char joiner;
2310 
2311 #ifdef JOINER
2312       joiner = JOINER;
2313 #else
2314       joiner = '_';
2315 #endif
2316 
2317       sprintf (type, "%c%c%.5u", method_type, joiner, initp);
2318     }
2319   else
2320     sprintf (type, "%c", method_type);
2321 
2322   fndecl = build_lang_decl (FUNCTION_DECL,
2323 			    get_file_function_name_long (type),
2324 			    build_function_type (void_type_node,
2325 						 void_list_node));
2326   start_preparsed_function (fndecl, /*attrs=*/NULL_TREE, SF_PRE_PARSED);
2327 
2328   /* It can be a static function as long as collect2 does not have
2329      to scan the object file to find its ctor/dtor routine.  */
2330   TREE_PUBLIC (current_function_decl) = ! targetm.have_ctors_dtors;
2331 
2332   /* Mark this declaration as used to avoid spurious warnings.  */
2333   TREE_USED (current_function_decl) = 1;
2334 
2335   /* Mark this function as a global constructor or destructor.  */
2336   if (method_type == 'I')
2337     DECL_GLOBAL_CTOR_P (current_function_decl) = 1;
2338   else
2339     DECL_GLOBAL_DTOR_P (current_function_decl) = 1;
2340   DECL_LANG_SPECIFIC (current_function_decl)->decl_flags.u2sel = 1;
2341 
2342   body = begin_compound_stmt (BCS_FN_BODY);
2343 
2344   /* We cannot allow these functions to be elided, even if they do not
2345      have external linkage.  And, there's no point in deferring
2346      compilation of these functions; they're all going to have to be
2347      out anyhow.  */
2348   DECL_INLINE (current_function_decl) = 0;
2349   DECL_UNINLINABLE (current_function_decl) = 1;
2350 
2351   return body;
2352 }
2353 
2354 /* Finish the process of running a particular set of global constructors
2355    or destructors.  Subroutine of do_[cd]tors.  */
2356 
2357 static void
finish_objects(int method_type,int initp,tree body)2358 finish_objects (int method_type, int initp, tree body)
2359 {
2360   tree fn;
2361 
2362   /* Finish up.  */
2363   finish_compound_stmt (body);
2364   fn = finish_function (0);
2365   expand_or_defer_fn (fn);
2366 
2367   /* When only doing semantic analysis, and no RTL generation, we
2368      can't call functions that directly emit assembly code; there is
2369      no assembly file in which to put the code.  */
2370   if (flag_syntax_only)
2371     return;
2372 
2373   if (targetm.have_ctors_dtors)
2374     {
2375       rtx fnsym = XEXP (DECL_RTL (fn), 0);
2376       cgraph_mark_needed_node (cgraph_node (fn));
2377       if (method_type == 'I')
2378 	(* targetm.asm_out.constructor) (fnsym, initp);
2379       else
2380 	(* targetm.asm_out.destructor) (fnsym, initp);
2381     }
2382 }
2383 
2384 /* The names of the parameters to the function created to handle
2385    initializations and destructions for objects with static storage
2386    duration.  */
2387 #define INITIALIZE_P_IDENTIFIER "__initialize_p"
2388 #define PRIORITY_IDENTIFIER "__priority"
2389 
2390 /* The name of the function we create to handle initializations and
2391    destructions for objects with static storage duration.  */
2392 #define SSDF_IDENTIFIER "__static_initialization_and_destruction"
2393 
2394 /* The declaration for the __INITIALIZE_P argument.  */
2395 static GTY(()) tree initialize_p_decl;
2396 
2397 /* The declaration for the __PRIORITY argument.  */
2398 static GTY(()) tree priority_decl;
2399 
2400 /* The declaration for the static storage duration function.  */
2401 static GTY(()) tree ssdf_decl;
2402 
2403 /* All the static storage duration functions created in this
2404    translation unit.  */
2405 static GTY(()) VEC(tree,gc) *ssdf_decls;
2406 
2407 /* A map from priority levels to information about that priority
2408    level.  There may be many such levels, so efficient lookup is
2409    important.  */
2410 static splay_tree priority_info_map;
2411 
2412 /* Begins the generation of the function that will handle all
2413    initialization and destruction of objects with static storage
2414    duration.  The function generated takes two parameters of type
2415    `int': __INITIALIZE_P and __PRIORITY.  If __INITIALIZE_P is
2416    nonzero, it performs initializations.  Otherwise, it performs
2417    destructions.  It only performs those initializations or
2418    destructions with the indicated __PRIORITY.  The generated function
2419    returns no value.
2420 
2421    It is assumed that this function will only be called once per
2422    translation unit.  */
2423 
2424 static tree
start_static_storage_duration_function(unsigned count)2425 start_static_storage_duration_function (unsigned count)
2426 {
2427   tree parm_types;
2428   tree type;
2429   tree body;
2430   char id[sizeof (SSDF_IDENTIFIER) + 1 /* '\0' */ + 32];
2431 
2432   /* Create the identifier for this function.  It will be of the form
2433      SSDF_IDENTIFIER_<number>.  */
2434   sprintf (id, "%s_%u", SSDF_IDENTIFIER, count);
2435 
2436   /* Create the parameters.  */
2437   parm_types = void_list_node;
2438   parm_types = tree_cons (NULL_TREE, integer_type_node, parm_types);
2439   parm_types = tree_cons (NULL_TREE, integer_type_node, parm_types);
2440   type = build_function_type (void_type_node, parm_types);
2441 
2442   /* Create the FUNCTION_DECL itself.  */
2443   ssdf_decl = build_lang_decl (FUNCTION_DECL,
2444 			       get_identifier (id),
2445 			       type);
2446   TREE_PUBLIC (ssdf_decl) = 0;
2447   DECL_ARTIFICIAL (ssdf_decl) = 1;
2448 
2449   /* Put this function in the list of functions to be called from the
2450      static constructors and destructors.  */
2451   if (!ssdf_decls)
2452     {
2453       ssdf_decls = VEC_alloc (tree, gc, 32);
2454 
2455       /* Take this opportunity to initialize the map from priority
2456 	 numbers to information about that priority level.  */
2457       priority_info_map = splay_tree_new (splay_tree_compare_ints,
2458 					  /*delete_key_fn=*/0,
2459 					  /*delete_value_fn=*/
2460 					  (splay_tree_delete_value_fn) &free);
2461 
2462       /* We always need to generate functions for the
2463 	 DEFAULT_INIT_PRIORITY so enter it now.  That way when we walk
2464 	 priorities later, we'll be sure to find the
2465 	 DEFAULT_INIT_PRIORITY.  */
2466       get_priority_info (DEFAULT_INIT_PRIORITY);
2467     }
2468 
2469   VEC_safe_push (tree, gc, ssdf_decls, ssdf_decl);
2470 
2471   /* Create the argument list.  */
2472   initialize_p_decl = cp_build_parm_decl
2473     (get_identifier (INITIALIZE_P_IDENTIFIER), integer_type_node);
2474   DECL_CONTEXT (initialize_p_decl) = ssdf_decl;
2475   TREE_USED (initialize_p_decl) = 1;
2476   priority_decl = cp_build_parm_decl
2477     (get_identifier (PRIORITY_IDENTIFIER), integer_type_node);
2478   DECL_CONTEXT (priority_decl) = ssdf_decl;
2479   TREE_USED (priority_decl) = 1;
2480 
2481   TREE_CHAIN (initialize_p_decl) = priority_decl;
2482   DECL_ARGUMENTS (ssdf_decl) = initialize_p_decl;
2483 
2484   /* Put the function in the global scope.  */
2485   pushdecl (ssdf_decl);
2486 
2487   /* Start the function itself.  This is equivalent to declaring the
2488      function as:
2489 
2490        static void __ssdf (int __initialize_p, init __priority_p);
2491 
2492      It is static because we only need to call this function from the
2493      various constructor and destructor functions for this module.  */
2494   start_preparsed_function (ssdf_decl,
2495 			    /*attrs=*/NULL_TREE,
2496 			    SF_PRE_PARSED);
2497 
2498   /* Set up the scope of the outermost block in the function.  */
2499   body = begin_compound_stmt (BCS_FN_BODY);
2500 
2501   /* This function must not be deferred because we are depending on
2502      its compilation to tell us what is TREE_SYMBOL_REFERENCED.  */
2503   DECL_INLINE (ssdf_decl) = 0;
2504   DECL_UNINLINABLE (ssdf_decl) = 1;
2505 
2506   return body;
2507 }
2508 
2509 /* Finish the generation of the function which performs initialization
2510    and destruction of objects with static storage duration.  After
2511    this point, no more such objects can be created.  */
2512 
2513 static void
finish_static_storage_duration_function(tree body)2514 finish_static_storage_duration_function (tree body)
2515 {
2516   /* Close out the function.  */
2517   finish_compound_stmt (body);
2518   expand_or_defer_fn (finish_function (0));
2519 }
2520 
2521 /* Return the information about the indicated PRIORITY level.  If no
2522    code to handle this level has yet been generated, generate the
2523    appropriate prologue.  */
2524 
2525 static priority_info
get_priority_info(int priority)2526 get_priority_info (int priority)
2527 {
2528   priority_info pi;
2529   splay_tree_node n;
2530 
2531   n = splay_tree_lookup (priority_info_map,
2532 			 (splay_tree_key) priority);
2533   if (!n)
2534     {
2535       /* Create a new priority information structure, and insert it
2536 	 into the map.  */
2537       pi = XNEW (struct priority_info_s);
2538       pi->initializations_p = 0;
2539       pi->destructions_p = 0;
2540       splay_tree_insert (priority_info_map,
2541 			 (splay_tree_key) priority,
2542 			 (splay_tree_value) pi);
2543     }
2544   else
2545     pi = (priority_info) n->value;
2546 
2547   return pi;
2548 }
2549 
2550 /* The effective initialization priority of a DECL.  */
2551 
2552 #define DECL_EFFECTIVE_INIT_PRIORITY(decl)				      \
2553 	((!DECL_HAS_INIT_PRIORITY_P (decl) || DECL_INIT_PRIORITY (decl) == 0) \
2554 	 ? DEFAULT_INIT_PRIORITY : DECL_INIT_PRIORITY (decl))
2555 
2556 /* Whether a DECL needs a guard to protect it against multiple
2557    initialization.  */
2558 
2559 #define NEEDS_GUARD_P(decl) (TREE_PUBLIC (decl) && (DECL_COMMON (decl)      \
2560 						    || DECL_ONE_ONLY (decl) \
2561 						    || DECL_WEAK (decl)))
2562 
2563 /* Set up to handle the initialization or destruction of DECL.  If
2564    INITP is nonzero, we are initializing the variable.  Otherwise, we
2565    are destroying it.  */
2566 
2567 static void
one_static_initialization_or_destruction(tree decl,tree init,bool initp)2568 one_static_initialization_or_destruction (tree decl, tree init, bool initp)
2569 {
2570   tree guard_if_stmt = NULL_TREE;
2571   tree guard;
2572 
2573   /* If we are supposed to destruct and there's a trivial destructor,
2574      nothing has to be done.  */
2575   if (!initp
2576       && TYPE_HAS_TRIVIAL_DESTRUCTOR (TREE_TYPE (decl)))
2577     return;
2578 
2579   /* Trick the compiler into thinking we are at the file and line
2580      where DECL was declared so that error-messages make sense, and so
2581      that the debugger will show somewhat sensible file and line
2582      information.  */
2583   input_location = DECL_SOURCE_LOCATION (decl);
2584 
2585   /* Because of:
2586 
2587        [class.access.spec]
2588 
2589        Access control for implicit calls to the constructors,
2590        the conversion functions, or the destructor called to
2591        create and destroy a static data member is performed as
2592        if these calls appeared in the scope of the member's
2593        class.
2594 
2595      we pretend we are in a static member function of the class of
2596      which the DECL is a member.  */
2597   if (member_p (decl))
2598     {
2599       DECL_CONTEXT (current_function_decl) = DECL_CONTEXT (decl);
2600       DECL_STATIC_FUNCTION_P (current_function_decl) = 1;
2601     }
2602 
2603   /* Assume we don't need a guard.  */
2604   guard = NULL_TREE;
2605   /* We need a guard if this is an object with external linkage that
2606      might be initialized in more than one place.  (For example, a
2607      static data member of a template, when the data member requires
2608      construction.)  */
2609   if (NEEDS_GUARD_P (decl))
2610     {
2611       tree guard_cond;
2612 
2613       guard = get_guard (decl);
2614 
2615       /* When using __cxa_atexit, we just check the GUARD as we would
2616 	 for a local static.  */
2617       if (flag_use_cxa_atexit)
2618 	{
2619 	  /* When using __cxa_atexit, we never try to destroy
2620 	     anything from a static destructor.  */
2621 	  gcc_assert (initp);
2622 	  guard_cond = get_guard_cond (guard);
2623 	}
2624       /* If we don't have __cxa_atexit, then we will be running
2625 	 destructors from .fini sections, or their equivalents.  So,
2626 	 we need to know how many times we've tried to initialize this
2627 	 object.  We do initializations only if the GUARD is zero,
2628 	 i.e., if we are the first to initialize the variable.  We do
2629 	 destructions only if the GUARD is one, i.e., if we are the
2630 	 last to destroy the variable.  */
2631       else if (initp)
2632 	guard_cond
2633 	  = cp_build_binary_op (EQ_EXPR,
2634 				build_unary_op (PREINCREMENT_EXPR,
2635 						guard,
2636 						/*noconvert=*/1),
2637 				integer_one_node);
2638       else
2639 	guard_cond
2640 	  = cp_build_binary_op (EQ_EXPR,
2641 				build_unary_op (PREDECREMENT_EXPR,
2642 						guard,
2643 						/*noconvert=*/1),
2644 				integer_zero_node);
2645 
2646       guard_if_stmt = begin_if_stmt ();
2647       finish_if_stmt_cond (guard_cond, guard_if_stmt);
2648     }
2649 
2650 
2651   /* If we're using __cxa_atexit, we have not already set the GUARD,
2652      so we must do so now.  */
2653   if (guard && initp && flag_use_cxa_atexit)
2654     finish_expr_stmt (set_guard (guard));
2655 
2656   /* Perform the initialization or destruction.  */
2657   if (initp)
2658     {
2659       if (init)
2660 	finish_expr_stmt (init);
2661 
2662       /* If we're using __cxa_atexit, register a function that calls the
2663 	 destructor for the object.  */
2664       if (flag_use_cxa_atexit)
2665 	finish_expr_stmt (register_dtor_fn (decl));
2666     }
2667   else
2668     finish_expr_stmt (build_cleanup (decl));
2669 
2670   /* Finish the guard if-stmt, if necessary.  */
2671   if (guard)
2672     {
2673       finish_then_clause (guard_if_stmt);
2674       finish_if_stmt (guard_if_stmt);
2675     }
2676 
2677   /* Now that we're done with DECL we don't need to pretend to be a
2678      member of its class any longer.  */
2679   DECL_CONTEXT (current_function_decl) = NULL_TREE;
2680   DECL_STATIC_FUNCTION_P (current_function_decl) = 0;
2681 }
2682 
2683 /* Generate code to do the initialization or destruction of the decls in VARS,
2684    a TREE_LIST of VAR_DECL with static storage duration.
2685    Whether initialization or destruction is performed is specified by INITP.  */
2686 
2687 static void
do_static_initialization_or_destruction(tree vars,bool initp)2688 do_static_initialization_or_destruction (tree vars, bool initp)
2689 {
2690   tree node, init_if_stmt, cond;
2691 
2692   /* Build the outer if-stmt to check for initialization or destruction.  */
2693   init_if_stmt = begin_if_stmt ();
2694   cond = initp ? integer_one_node : integer_zero_node;
2695   cond = cp_build_binary_op (EQ_EXPR,
2696 				  initialize_p_decl,
2697 				  cond);
2698   finish_if_stmt_cond (cond, init_if_stmt);
2699 
2700   node = vars;
2701   do {
2702     tree decl = TREE_VALUE (node);
2703     tree priority_if_stmt;
2704     int priority;
2705     priority_info pi;
2706 
2707     /* If we don't need a destructor, there's nothing to do.  Avoid
2708        creating a possibly empty if-stmt.  */
2709     if (!initp && TYPE_HAS_TRIVIAL_DESTRUCTOR (TREE_TYPE (decl)))
2710       {
2711 	node = TREE_CHAIN (node);
2712 	continue;
2713       }
2714 
2715     /* Remember that we had an initialization or finalization at this
2716        priority.  */
2717     priority = DECL_EFFECTIVE_INIT_PRIORITY (decl);
2718     pi = get_priority_info (priority);
2719     if (initp)
2720       pi->initializations_p = 1;
2721     else
2722       pi->destructions_p = 1;
2723 
2724     /* Conditionalize this initialization on being in the right priority
2725        and being initializing/finalizing appropriately.  */
2726     priority_if_stmt = begin_if_stmt ();
2727     cond = cp_build_binary_op (EQ_EXPR,
2728 			       priority_decl,
2729 			       build_int_cst (NULL_TREE, priority));
2730     finish_if_stmt_cond (cond, priority_if_stmt);
2731 
2732     /* Process initializers with same priority.  */
2733     for (; node
2734 	   && DECL_EFFECTIVE_INIT_PRIORITY (TREE_VALUE (node)) == priority;
2735 	 node = TREE_CHAIN (node))
2736       /* Do one initialization or destruction.  */
2737       one_static_initialization_or_destruction (TREE_VALUE (node),
2738 						TREE_PURPOSE (node), initp);
2739 
2740     /* Finish up the priority if-stmt body.  */
2741     finish_then_clause (priority_if_stmt);
2742     finish_if_stmt (priority_if_stmt);
2743 
2744   } while (node);
2745 
2746   /* Finish up the init/destruct if-stmt body.  */
2747   finish_then_clause (init_if_stmt);
2748   finish_if_stmt (init_if_stmt);
2749 }
2750 
2751 /* VARS is a list of variables with static storage duration which may
2752    need initialization and/or finalization.  Remove those variables
2753    that don't really need to be initialized or finalized, and return
2754    the resulting list.  The order in which the variables appear in
2755    VARS is in reverse order of the order in which they should actually
2756    be initialized.  The list we return is in the unreversed order;
2757    i.e., the first variable should be initialized first.  */
2758 
2759 static tree
prune_vars_needing_no_initialization(tree * vars)2760 prune_vars_needing_no_initialization (tree *vars)
2761 {
2762   tree *var = vars;
2763   tree result = NULL_TREE;
2764 
2765   while (*var)
2766     {
2767       tree t = *var;
2768       tree decl = TREE_VALUE (t);
2769       tree init = TREE_PURPOSE (t);
2770 
2771       /* Deal gracefully with error.  */
2772       if (decl == error_mark_node)
2773 	{
2774 	  var = &TREE_CHAIN (t);
2775 	  continue;
2776 	}
2777 
2778       /* The only things that can be initialized are variables.  */
2779       gcc_assert (TREE_CODE (decl) == VAR_DECL);
2780 
2781       /* If this object is not defined, we don't need to do anything
2782 	 here.  */
2783       if (DECL_EXTERNAL (decl))
2784 	{
2785 	  var = &TREE_CHAIN (t);
2786 	  continue;
2787 	}
2788 
2789       /* Also, if the initializer already contains errors, we can bail
2790 	 out now.  */
2791       if (init && TREE_CODE (init) == TREE_LIST
2792 	  && value_member (error_mark_node, init))
2793 	{
2794 	  var = &TREE_CHAIN (t);
2795 	  continue;
2796 	}
2797 
2798       /* This variable is going to need initialization and/or
2799 	 finalization, so we add it to the list.  */
2800       *var = TREE_CHAIN (t);
2801       TREE_CHAIN (t) = result;
2802       result = t;
2803     }
2804 
2805   return result;
2806 }
2807 
2808 /* Make sure we have told the back end about all the variables in
2809    VARS.  */
2810 
2811 static void
write_out_vars(tree vars)2812 write_out_vars (tree vars)
2813 {
2814   tree v;
2815 
2816   for (v = vars; v; v = TREE_CHAIN (v))
2817     {
2818       tree var = TREE_VALUE (v);
2819       if (!var_finalized_p (var))
2820 	{
2821 	  import_export_decl (var);
2822 	  rest_of_decl_compilation (var, 1, 1);
2823 	}
2824     }
2825 }
2826 
2827 /* Generate a static constructor (if CONSTRUCTOR_P) or destructor
2828    (otherwise) that will initialize all gobal objects with static
2829    storage duration having the indicated PRIORITY.  */
2830 
2831 static void
generate_ctor_or_dtor_function(bool constructor_p,int priority,location_t * locus)2832 generate_ctor_or_dtor_function (bool constructor_p, int priority,
2833 				location_t *locus)
2834 {
2835   char function_key;
2836   tree arguments;
2837   tree fndecl;
2838   tree body;
2839   size_t i;
2840 
2841   input_location = *locus;
2842 #ifdef USE_MAPPED_LOCATION
2843   /* ??? */
2844 #else
2845   locus->line++;
2846 #endif
2847 
2848   /* We use `I' to indicate initialization and `D' to indicate
2849      destruction.  */
2850   function_key = constructor_p ? 'I' : 'D';
2851 
2852   /* We emit the function lazily, to avoid generating empty
2853      global constructors and destructors.  */
2854   body = NULL_TREE;
2855 
2856   /* For Objective-C++, we may need to initialize metadata found in this module.
2857      This must be done _before_ any other static initializations.  */
2858   if (c_dialect_objc () && (priority == DEFAULT_INIT_PRIORITY)
2859       && constructor_p && objc_static_init_needed_p ())
2860     {
2861       body = start_objects (function_key, priority);
2862       static_ctors = objc_generate_static_init_call (static_ctors);
2863     }
2864 
2865   /* Call the static storage duration function with appropriate
2866      arguments.  */
2867   for (i = 0; VEC_iterate (tree, ssdf_decls, i, fndecl); ++i)
2868     {
2869       /* Calls to pure or const functions will expand to nothing.  */
2870       if (! (flags_from_decl_or_type (fndecl) & (ECF_CONST | ECF_PURE)))
2871 	{
2872 	  if (! body)
2873 	    body = start_objects (function_key, priority);
2874 
2875 	  arguments = tree_cons (NULL_TREE,
2876 				 build_int_cst (NULL_TREE, priority),
2877 				 NULL_TREE);
2878 	  arguments = tree_cons (NULL_TREE,
2879 				 build_int_cst (NULL_TREE, constructor_p),
2880 				 arguments);
2881 	  finish_expr_stmt (build_function_call (fndecl, arguments));
2882 	}
2883     }
2884 
2885   /* If we're generating code for the DEFAULT_INIT_PRIORITY, throw in
2886      calls to any functions marked with attributes indicating that
2887      they should be called at initialization- or destruction-time.  */
2888   if (priority == DEFAULT_INIT_PRIORITY)
2889     {
2890       tree fns;
2891 
2892       for (fns = constructor_p ? static_ctors : static_dtors;
2893 	   fns;
2894 	   fns = TREE_CHAIN (fns))
2895 	{
2896 	  fndecl = TREE_VALUE (fns);
2897 
2898 	  /* Calls to pure/const functions will expand to nothing.  */
2899 	  if (! (flags_from_decl_or_type (fndecl) & (ECF_CONST | ECF_PURE)))
2900 	    {
2901 	      if (! body)
2902 		body = start_objects (function_key, priority);
2903 	      finish_expr_stmt (build_function_call (fndecl, NULL_TREE));
2904 	    }
2905 	}
2906     }
2907 
2908   /* Close out the function.  */
2909   if (body)
2910     finish_objects (function_key, priority, body);
2911 }
2912 
2913 /* Generate constructor and destructor functions for the priority
2914    indicated by N.  */
2915 
2916 static int
generate_ctor_and_dtor_functions_for_priority(splay_tree_node n,void * data)2917 generate_ctor_and_dtor_functions_for_priority (splay_tree_node n, void * data)
2918 {
2919   location_t *locus = (location_t *) data;
2920   int priority = (int) n->key;
2921   priority_info pi = (priority_info) n->value;
2922 
2923   /* Generate the functions themselves, but only if they are really
2924      needed.  */
2925   if (pi->initializations_p
2926       || (priority == DEFAULT_INIT_PRIORITY && static_ctors))
2927     generate_ctor_or_dtor_function (/*constructor_p=*/true, priority, locus);
2928   if (pi->destructions_p
2929       || (priority == DEFAULT_INIT_PRIORITY && static_dtors))
2930     generate_ctor_or_dtor_function (/*constructor_p=*/false, priority, locus);
2931 
2932   /* Keep iterating.  */
2933   return 0;
2934 }
2935 
2936 /* Called via LANGHOOK_CALLGRAPH_ANALYZE_EXPR.  It is supposed to mark
2937    decls referenced from frontend specific constructs; it will be called
2938    only for language-specific tree nodes.
2939 
2940    Here we must deal with member pointers.  */
2941 
2942 tree
cxx_callgraph_analyze_expr(tree * tp,int * walk_subtrees ATTRIBUTE_UNUSED,tree from ATTRIBUTE_UNUSED)2943 cxx_callgraph_analyze_expr (tree *tp, int *walk_subtrees ATTRIBUTE_UNUSED,
2944 			    tree from ATTRIBUTE_UNUSED)
2945 {
2946   tree t = *tp;
2947 
2948   switch (TREE_CODE (t))
2949     {
2950     case PTRMEM_CST:
2951       if (TYPE_PTRMEMFUNC_P (TREE_TYPE (t)))
2952 	cgraph_mark_needed_node (cgraph_node (PTRMEM_CST_MEMBER (t)));
2953       break;
2954     case BASELINK:
2955       if (TREE_CODE (BASELINK_FUNCTIONS (t)) == FUNCTION_DECL)
2956 	cgraph_mark_needed_node (cgraph_node (BASELINK_FUNCTIONS (t)));
2957       break;
2958     case VAR_DECL:
2959       if (DECL_VTABLE_OR_VTT_P (t))
2960 	{
2961 	  /* The ABI requires that all virtual tables be emitted
2962 	     whenever one of them is.  */
2963 	  tree vtbl;
2964 	  for (vtbl = CLASSTYPE_VTABLES (DECL_CONTEXT (t));
2965 	       vtbl;
2966 	       vtbl = TREE_CHAIN (vtbl))
2967 	    mark_decl_referenced (vtbl);
2968 	}
2969       else if (DECL_CONTEXT (t)
2970 	       && TREE_CODE (DECL_CONTEXT (t)) == FUNCTION_DECL)
2971 	/* If we need a static variable in a function, then we
2972 	   need the containing function.  */
2973 	mark_decl_referenced (DECL_CONTEXT (t));
2974       break;
2975     default:
2976       break;
2977     }
2978 
2979   return NULL;
2980 }
2981 
2982 /* Java requires that we be able to reference a local address for a
2983    method, and not be confused by PLT entries.  If hidden aliases are
2984    supported, emit one for each java function that we've emitted.  */
2985 
2986 static void
build_java_method_aliases(void)2987 build_java_method_aliases (void)
2988 {
2989   struct cgraph_node *node;
2990 
2991 #ifndef HAVE_GAS_HIDDEN
2992   return;
2993 #endif
2994 
2995   for (node = cgraph_nodes; node ; node = node->next)
2996     {
2997       tree fndecl = node->decl;
2998 
2999       if (TREE_ASM_WRITTEN (fndecl)
3000 	  && DECL_CONTEXT (fndecl)
3001 	  && TYPE_P (DECL_CONTEXT (fndecl))
3002 	  && TYPE_FOR_JAVA (DECL_CONTEXT (fndecl))
3003 	  && TARGET_USE_LOCAL_THUNK_ALIAS_P (fndecl))
3004 	{
3005 	  /* Mangle the name in a predictable way; we need to reference
3006 	     this from a java compiled object file.  */
3007 	  tree oid, nid, alias;
3008 	  const char *oname;
3009 	  char *nname;
3010 
3011 	  oid = DECL_ASSEMBLER_NAME (fndecl);
3012 	  oname = IDENTIFIER_POINTER (oid);
3013 	  gcc_assert (oname[0] == '_' && oname[1] == 'Z');
3014 	  nname = ACONCAT (("_ZGA", oname+2, NULL));
3015 	  nid = get_identifier (nname);
3016 
3017 	  alias = make_alias_for (fndecl, nid);
3018 	  TREE_PUBLIC (alias) = 1;
3019 	  DECL_VISIBILITY (alias) = VISIBILITY_HIDDEN;
3020 
3021 	  assemble_alias (alias, oid);
3022 	}
3023     }
3024 }
3025 
3026 /* This routine is called from the last rule in yyparse ().
3027    Its job is to create all the code needed to initialize and
3028    destroy the global aggregates.  We do the destruction
3029    first, since that way we only need to reverse the decls once.  */
3030 
3031 void
cp_finish_file(void)3032 cp_finish_file (void)
3033 {
3034   tree vars;
3035   bool reconsider;
3036   size_t i;
3037   location_t locus;
3038   unsigned ssdf_count = 0;
3039   int retries = 0;
3040   tree decl;
3041 
3042   locus = input_location;
3043   at_eof = 1;
3044 
3045   /* Bad parse errors.  Just forget about it.  */
3046   if (! global_bindings_p () || current_class_type || decl_namespace_list)
3047     return;
3048 
3049   if (pch_file)
3050     c_common_write_pch ();
3051 
3052 #ifdef USE_MAPPED_LOCATION
3053   /* FIXME - huh? */
3054 #else
3055   /* Otherwise, GDB can get confused, because in only knows
3056      about source for LINENO-1 lines.  */
3057   input_line -= 1;
3058 #endif
3059 
3060   /* We now have to write out all the stuff we put off writing out.
3061      These include:
3062 
3063        o Template specializations that we have not yet instantiated,
3064 	 but which are needed.
3065        o Initialization and destruction for non-local objects with
3066 	 static storage duration.  (Local objects with static storage
3067 	 duration are initialized when their scope is first entered,
3068 	 and are cleaned up via atexit.)
3069        o Virtual function tables.
3070 
3071      All of these may cause others to be needed.  For example,
3072      instantiating one function may cause another to be needed, and
3073      generating the initializer for an object may cause templates to be
3074      instantiated, etc., etc.  */
3075 
3076   timevar_push (TV_VARCONST);
3077 
3078   emit_support_tinfos ();
3079 
3080   do
3081     {
3082       tree t;
3083       tree decl;
3084 
3085       reconsider = false;
3086 
3087       /* If there are templates that we've put off instantiating, do
3088 	 them now.  */
3089       instantiate_pending_templates (retries);
3090       ggc_collect ();
3091 
3092       /* Write out virtual tables as required.  Note that writing out
3093 	 the virtual table for a template class may cause the
3094 	 instantiation of members of that class.  If we write out
3095 	 vtables then we remove the class from our list so we don't
3096 	 have to look at it again.  */
3097 
3098       while (keyed_classes != NULL_TREE
3099 	     && maybe_emit_vtables (TREE_VALUE (keyed_classes)))
3100 	{
3101 	  reconsider = true;
3102 	  keyed_classes = TREE_CHAIN (keyed_classes);
3103 	}
3104 
3105       t = keyed_classes;
3106       if (t != NULL_TREE)
3107 	{
3108 	  tree next = TREE_CHAIN (t);
3109 
3110 	  while (next)
3111 	    {
3112 	      if (maybe_emit_vtables (TREE_VALUE (next)))
3113 		{
3114 		  reconsider = true;
3115 		  TREE_CHAIN (t) = TREE_CHAIN (next);
3116 		}
3117 	      else
3118 		t = next;
3119 
3120 	      next = TREE_CHAIN (t);
3121 	    }
3122 	}
3123 
3124       /* Write out needed type info variables.  We have to be careful
3125 	 looping through unemitted decls, because emit_tinfo_decl may
3126 	 cause other variables to be needed. New elements will be
3127 	 appended, and we remove from the vector those that actually
3128 	 get emitted.  */
3129       for (i = VEC_length (tree, unemitted_tinfo_decls);
3130 	   VEC_iterate (tree, unemitted_tinfo_decls, --i, t);)
3131 	if (emit_tinfo_decl (t))
3132 	  {
3133 	    reconsider = true;
3134 	    VEC_unordered_remove (tree, unemitted_tinfo_decls, i);
3135 	  }
3136 
3137       /* The list of objects with static storage duration is built up
3138 	 in reverse order.  We clear STATIC_AGGREGATES so that any new
3139 	 aggregates added during the initialization of these will be
3140 	 initialized in the correct order when we next come around the
3141 	 loop.  */
3142       vars = prune_vars_needing_no_initialization (&static_aggregates);
3143 
3144       if (vars)
3145 	{
3146 	  /* We need to start a new initialization function each time
3147 	     through the loop.  That's because we need to know which
3148 	     vtables have been referenced, and TREE_SYMBOL_REFERENCED
3149 	     isn't computed until a function is finished, and written
3150 	     out.  That's a deficiency in the back-end.  When this is
3151 	     fixed, these initialization functions could all become
3152 	     inline, with resulting performance improvements.  */
3153 	  tree ssdf_body;
3154 
3155 	  /* Set the line and file, so that it is obviously not from
3156 	     the source file.  */
3157 	  input_location = locus;
3158 	  ssdf_body = start_static_storage_duration_function (ssdf_count);
3159 
3160 	  /* Make sure the back end knows about all the variables.  */
3161 	  write_out_vars (vars);
3162 
3163 	  /* First generate code to do all the initializations.  */
3164 	  if (vars)
3165 	    do_static_initialization_or_destruction (vars, /*initp=*/true);
3166 
3167 	  /* Then, generate code to do all the destructions.  Do these
3168 	     in reverse order so that the most recently constructed
3169 	     variable is the first destroyed.  If we're using
3170 	     __cxa_atexit, then we don't need to do this; functions
3171 	     were registered at initialization time to destroy the
3172 	     local statics.  */
3173 	  if (!flag_use_cxa_atexit && vars)
3174 	    {
3175 	      vars = nreverse (vars);
3176 	      do_static_initialization_or_destruction (vars, /*initp=*/false);
3177 	    }
3178 	  else
3179 	    vars = NULL_TREE;
3180 
3181 	  /* Finish up the static storage duration function for this
3182 	     round.  */
3183 	  input_location = locus;
3184 	  finish_static_storage_duration_function (ssdf_body);
3185 
3186 	  /* All those initializations and finalizations might cause
3187 	     us to need more inline functions, more template
3188 	     instantiations, etc.  */
3189 	  reconsider = true;
3190 	  ssdf_count++;
3191 #ifdef USE_MAPPED_LOCATION
3192 	  /* ??? */
3193 #else
3194 	  locus.line++;
3195 #endif
3196 	}
3197 
3198       /* Go through the set of inline functions whose bodies have not
3199 	 been emitted yet.  If out-of-line copies of these functions
3200 	 are required, emit them.  */
3201       for (i = 0; VEC_iterate (tree, deferred_fns, i, decl); ++i)
3202 	{
3203 	  /* Does it need synthesizing?  */
3204 	  if (DECL_ARTIFICIAL (decl) && ! DECL_INITIAL (decl)
3205 	      && (! DECL_REALLY_EXTERN (decl) || DECL_INLINE (decl)))
3206 	    {
3207 	      /* Even though we're already at the top-level, we push
3208 		 there again.  That way, when we pop back a few lines
3209 		 hence, all of our state is restored.  Otherwise,
3210 		 finish_function doesn't clean things up, and we end
3211 		 up with CURRENT_FUNCTION_DECL set.  */
3212 	      push_to_top_level ();
3213 	      /* The decl's location will mark where it was first
3214 		 needed.  Save that so synthesize method can indicate
3215 		 where it was needed from, in case of error  */
3216 	      input_location = DECL_SOURCE_LOCATION (decl);
3217 	      synthesize_method (decl);
3218 	      pop_from_top_level ();
3219 	      reconsider = true;
3220 	    }
3221 
3222 	  if (!DECL_SAVED_TREE (decl))
3223 	    continue;
3224 
3225 	  /* We lie to the back-end, pretending that some functions
3226 	     are not defined when they really are.  This keeps these
3227 	     functions from being put out unnecessarily.  But, we must
3228 	     stop lying when the functions are referenced, or if they
3229 	     are not comdat since they need to be put out now.  If
3230 	     DECL_INTERFACE_KNOWN, then we have already set
3231 	     DECL_EXTERNAL appropriately, so there's no need to check
3232 	     again, and we do not want to clear DECL_EXTERNAL if a
3233 	     previous call to import_export_decl set it.
3234 
3235 	     This is done in a separate for cycle, because if some
3236 	     deferred function is contained in another deferred
3237 	     function later in deferred_fns varray,
3238 	     rest_of_compilation would skip this function and we
3239 	     really cannot expand the same function twice.  */
3240 	  import_export_decl (decl);
3241 	  if (DECL_NOT_REALLY_EXTERN (decl)
3242 	      && DECL_INITIAL (decl)
3243 	      && decl_needed_p (decl))
3244 	    DECL_EXTERNAL (decl) = 0;
3245 
3246 	  /* If we're going to need to write this function out, and
3247 	     there's already a body for it, create RTL for it now.
3248 	     (There might be no body if this is a method we haven't
3249 	     gotten around to synthesizing yet.)  */
3250 	  if (!DECL_EXTERNAL (decl)
3251 	      && decl_needed_p (decl)
3252 	      && !TREE_ASM_WRITTEN (decl)
3253 	      && !cgraph_node (decl)->local.finalized)
3254 	    {
3255 	      /* We will output the function; no longer consider it in this
3256 		 loop.  */
3257 	      DECL_DEFER_OUTPUT (decl) = 0;
3258 	      /* Generate RTL for this function now that we know we
3259 		 need it.  */
3260 	      expand_or_defer_fn (decl);
3261 	      /* If we're compiling -fsyntax-only pretend that this
3262 		 function has been written out so that we don't try to
3263 		 expand it again.  */
3264 	      if (flag_syntax_only)
3265 		TREE_ASM_WRITTEN (decl) = 1;
3266 	      reconsider = true;
3267 	    }
3268 	}
3269 
3270       if (walk_namespaces (wrapup_globals_for_namespace, /*data=*/0))
3271 	reconsider = true;
3272 
3273       /* Static data members are just like namespace-scope globals.  */
3274       for (i = 0; VEC_iterate (tree, pending_statics, i, decl); ++i)
3275 	{
3276 	  if (var_finalized_p (decl) || DECL_REALLY_EXTERN (decl))
3277 	    continue;
3278 	  import_export_decl (decl);
3279 	  /* If this static data member is needed, provide it to the
3280 	     back end.  */
3281 	  if (DECL_NOT_REALLY_EXTERN (decl) && decl_needed_p (decl))
3282 	    DECL_EXTERNAL (decl) = 0;
3283 	}
3284       if (VEC_length (tree, pending_statics) != 0
3285 	  && wrapup_global_declarations (VEC_address (tree, pending_statics),
3286 					 VEC_length (tree, pending_statics)))
3287 	reconsider = true;
3288 
3289       retries++;
3290     }
3291   while (reconsider);
3292 
3293   /* All used inline functions must have a definition at this point.  */
3294   for (i = 0; VEC_iterate (tree, deferred_fns, i, decl); ++i)
3295     {
3296       if (/* Check online inline functions that were actually used.  */
3297 	  TREE_USED (decl) && DECL_DECLARED_INLINE_P (decl)
3298 	  /* If the definition actually was available here, then the
3299 	     fact that the function was not defined merely represents
3300 	     that for some reason (use of a template repository,
3301 	     #pragma interface, etc.) we decided not to emit the
3302 	     definition here.  */
3303 	  && !DECL_INITIAL (decl)
3304 	  /* An explicit instantiation can be used to specify
3305 	     that the body is in another unit. It will have
3306 	     already verified there was a definition.  */
3307 	  && !DECL_EXPLICIT_INSTANTIATION (decl))
3308 	{
3309 	  warning (0, "inline function %q+D used but never defined", decl);
3310 	  /* Avoid a duplicate warning from check_global_declaration_1.  */
3311 	  TREE_NO_WARNING (decl) = 1;
3312 	}
3313     }
3314 
3315   /* We give C linkage to static constructors and destructors.  */
3316   push_lang_context (lang_name_c);
3317 
3318   /* Generate initialization and destruction functions for all
3319      priorities for which they are required.  */
3320   if (priority_info_map)
3321     splay_tree_foreach (priority_info_map,
3322 			generate_ctor_and_dtor_functions_for_priority,
3323 			/*data=*/&locus);
3324   else
3325     {
3326       /* If we have a ctor or this is obj-c++ and we need a static init,
3327 	 call generate_ctor_or_dtor_function.  */
3328       if (static_ctors || (c_dialect_objc () && objc_static_init_needed_p ()))
3329 	generate_ctor_or_dtor_function (/*constructor_p=*/true,
3330 					DEFAULT_INIT_PRIORITY, &locus);
3331       if (static_dtors)
3332 	generate_ctor_or_dtor_function (/*constructor_p=*/false,
3333 					DEFAULT_INIT_PRIORITY, &locus);
3334     }
3335 
3336   /* We're done with the splay-tree now.  */
3337   if (priority_info_map)
3338     splay_tree_delete (priority_info_map);
3339 
3340   /* Generate any missing aliases.  */
3341   maybe_apply_pending_pragma_weaks ();
3342 
3343   /* We're done with static constructors, so we can go back to "C++"
3344      linkage now.  */
3345   pop_lang_context ();
3346 
3347   cgraph_finalize_compilation_unit ();
3348   cgraph_optimize ();
3349 
3350   /* Now, issue warnings about static, but not defined, functions,
3351      etc., and emit debugging information.  */
3352   walk_namespaces (wrapup_globals_for_namespace, /*data=*/&reconsider);
3353   if (VEC_length (tree, pending_statics) != 0)
3354     {
3355       check_global_declarations (VEC_address (tree, pending_statics),
3356 				 VEC_length (tree, pending_statics));
3357       emit_debug_global_declarations (VEC_address (tree, pending_statics),
3358 				      VEC_length (tree, pending_statics));
3359     }
3360 
3361   /* Generate hidden aliases for Java.  */
3362   build_java_method_aliases ();
3363 
3364   finish_repo ();
3365 
3366   /* The entire file is now complete.  If requested, dump everything
3367      to a file.  */
3368   {
3369     int flags;
3370     FILE *stream = dump_begin (TDI_tu, &flags);
3371 
3372     if (stream)
3373       {
3374 	dump_node (global_namespace, flags & ~TDF_SLIM, stream);
3375 	dump_end (TDI_tu, stream);
3376       }
3377   }
3378 
3379   timevar_pop (TV_VARCONST);
3380 
3381   if (flag_detailed_statistics)
3382     {
3383       dump_tree_statistics ();
3384       dump_time_statistics ();
3385     }
3386   input_location = locus;
3387 
3388 #ifdef ENABLE_CHECKING
3389   validate_conversion_obstack ();
3390 #endif /* ENABLE_CHECKING */
3391 }
3392 
3393 /* FN is an OFFSET_REF, DOTSTAR_EXPR or MEMBER_REF indicating the
3394    function to call in parse-tree form; it has not yet been
3395    semantically analyzed.  ARGS are the arguments to the function.
3396    They have already been semantically analyzed.  */
3397 
3398 tree
build_offset_ref_call_from_tree(tree fn,tree args)3399 build_offset_ref_call_from_tree (tree fn, tree args)
3400 {
3401   tree orig_fn;
3402   tree orig_args;
3403   tree expr;
3404   tree object;
3405 
3406   orig_fn = fn;
3407   orig_args = args;
3408   object = TREE_OPERAND (fn, 0);
3409 
3410   if (processing_template_decl)
3411     {
3412       gcc_assert (TREE_CODE (fn) == DOTSTAR_EXPR
3413 		  || TREE_CODE (fn) == MEMBER_REF);
3414       if (type_dependent_expression_p (fn)
3415 	  || any_type_dependent_arguments_p (args))
3416 	return build_min_nt (CALL_EXPR, fn, args, NULL_TREE);
3417 
3418       /* Transform the arguments and add the implicit "this"
3419 	 parameter.  That must be done before the FN is transformed
3420 	 because we depend on the form of FN.  */
3421       args = build_non_dependent_args (args);
3422       if (TREE_CODE (fn) == DOTSTAR_EXPR)
3423 	object = build_unary_op (ADDR_EXPR, object, 0);
3424       object = build_non_dependent_expr (object);
3425       args = tree_cons (NULL_TREE, object, args);
3426       /* Now that the arguments are done, transform FN.  */
3427       fn = build_non_dependent_expr (fn);
3428     }
3429 
3430   /* A qualified name corresponding to a bound pointer-to-member is
3431      represented as an OFFSET_REF:
3432 
3433 	struct B { void g(); };
3434 	void (B::*p)();
3435 	void B::g() { (this->*p)(); }  */
3436   if (TREE_CODE (fn) == OFFSET_REF)
3437     {
3438       tree object_addr = build_unary_op (ADDR_EXPR, object, 0);
3439       fn = TREE_OPERAND (fn, 1);
3440       fn = get_member_function_from_ptrfunc (&object_addr, fn);
3441       args = tree_cons (NULL_TREE, object_addr, args);
3442     }
3443 
3444   expr = build_function_call (fn, args);
3445   if (processing_template_decl && expr != error_mark_node)
3446     return build_min_non_dep (CALL_EXPR, expr, orig_fn, orig_args, NULL_TREE);
3447   return expr;
3448 }
3449 
3450 
3451 void
check_default_args(tree x)3452 check_default_args (tree x)
3453 {
3454   tree arg = TYPE_ARG_TYPES (TREE_TYPE (x));
3455   bool saw_def = false;
3456   int i = 0 - (TREE_CODE (TREE_TYPE (x)) == METHOD_TYPE);
3457   for (; arg && arg != void_list_node; arg = TREE_CHAIN (arg), ++i)
3458     {
3459       if (TREE_PURPOSE (arg))
3460 	saw_def = true;
3461       else if (saw_def)
3462 	{
3463 	  error ("default argument missing for parameter %P of %q+#D", i, x);
3464 	  TREE_PURPOSE (arg) = error_mark_node;
3465 	}
3466     }
3467 }
3468 
3469 /* Mark DECL (either a _DECL or a BASELINK) as "used" in the program.
3470    If DECL is a specialization or implicitly declared class member,
3471    generate the actual definition.  */
3472 
3473 void
mark_used(tree decl)3474 mark_used (tree decl)
3475 {
3476   HOST_WIDE_INT saved_processing_template_decl = 0;
3477 
3478   /* If DECL is a BASELINK for a single function, then treat it just
3479      like the DECL for the function.  Otherwise, if the BASELINK is
3480      for an overloaded function, we don't know which function was
3481      actually used until after overload resolution.  */
3482   if (TREE_CODE (decl) == BASELINK)
3483     {
3484       decl = BASELINK_FUNCTIONS (decl);
3485       if (really_overloaded_fn (decl))
3486 	return;
3487       decl = OVL_CURRENT (decl);
3488     }
3489 
3490   TREE_USED (decl) = 1;
3491   if (DECL_CLONED_FUNCTION_P (decl))
3492     TREE_USED (DECL_CLONED_FUNCTION (decl)) = 1;
3493   /* If we don't need a value, then we don't need to synthesize DECL.  */
3494   if (skip_evaluation)
3495     return;
3496   /* Normally, we can wait until instantiation-time to synthesize
3497      DECL.  However, if DECL is a static data member initialized with
3498      a constant, we need the value right now because a reference to
3499      such a data member is not value-dependent.  */
3500   if (TREE_CODE (decl) == VAR_DECL
3501       && DECL_INITIALIZED_BY_CONSTANT_EXPRESSION_P (decl)
3502       && DECL_CLASS_SCOPE_P (decl))
3503     {
3504       /* Don't try to instantiate members of dependent types.  We
3505 	 cannot just use dependent_type_p here because this function
3506 	 may be called from fold_non_dependent_expr, and then we may
3507 	 see dependent types, even though processing_template_decl
3508 	 will not be set.  */
3509       if (CLASSTYPE_TEMPLATE_INFO ((DECL_CONTEXT (decl)))
3510 	  && uses_template_parms (CLASSTYPE_TI_ARGS (DECL_CONTEXT (decl))))
3511 	return;
3512       /* Pretend that we are not in a template, even if we are, so
3513 	 that the static data member initializer will be processed.  */
3514       saved_processing_template_decl = processing_template_decl;
3515       processing_template_decl = 0;
3516     }
3517 
3518   if (processing_template_decl)
3519     return;
3520 
3521   if (TREE_CODE (decl) == FUNCTION_DECL && DECL_DECLARED_INLINE_P (decl)
3522       && !TREE_ASM_WRITTEN (decl))
3523     /* Remember it, so we can check it was defined.  */
3524     {
3525       if (DECL_DEFERRED_FN (decl))
3526 	return;
3527 
3528       /* Remember the current location for a function we will end up
3529 	 synthesizing.  Then we can inform the user where it was
3530 	 required in the case of error.  */
3531       if (DECL_ARTIFICIAL (decl) && DECL_NONSTATIC_MEMBER_FUNCTION_P (decl)
3532 	  && !DECL_THUNK_P (decl))
3533 	DECL_SOURCE_LOCATION (decl) = input_location;
3534 
3535       note_vague_linkage_fn (decl);
3536     }
3537 
3538   /* Is it a synthesized method that needs to be synthesized?  */
3539   if (TREE_CODE (decl) == FUNCTION_DECL
3540       && DECL_NONSTATIC_MEMBER_FUNCTION_P (decl)
3541       && DECL_ARTIFICIAL (decl)
3542       && !DECL_THUNK_P (decl)
3543       && ! DECL_INITIAL (decl)
3544       /* Kludge: don't synthesize for default args.  Unfortunately this
3545 	 rules out initializers of namespace-scoped objects too, but
3546 	 it's sort-of ok if the implicit ctor or dtor decl keeps
3547 	 pointing to the class location.  */
3548       && current_function_decl)
3549     {
3550       synthesize_method (decl);
3551       /* If we've already synthesized the method we don't need to
3552 	 do the instantiation test below.  */
3553     }
3554   else if ((DECL_NON_THUNK_FUNCTION_P (decl) || TREE_CODE (decl) == VAR_DECL)
3555 	   && DECL_LANG_SPECIFIC (decl) && DECL_TEMPLATE_INFO (decl)
3556 	   && (!DECL_EXPLICIT_INSTANTIATION (decl)
3557 	       || (TREE_CODE (decl) == FUNCTION_DECL
3558 		   && DECL_INLINE (DECL_TEMPLATE_RESULT
3559 				   (template_for_substitution (decl))))
3560 	       /* We need to instantiate static data members so that there
3561 		  initializers are available in integral constant
3562 		  expressions.  */
3563 	       || (TREE_CODE (decl) == VAR_DECL
3564 		   && DECL_INITIALIZED_BY_CONSTANT_EXPRESSION_P (decl))))
3565     /* If this is a function or variable that is an instance of some
3566        template, we now know that we will need to actually do the
3567        instantiation. We check that DECL is not an explicit
3568        instantiation because that is not checked in instantiate_decl.
3569 
3570        We put off instantiating functions in order to improve compile
3571        times.  Maintaining a stack of active functions is expensive,
3572        and the inliner knows to instantiate any functions it might
3573        need.  Therefore, we always try to defer instantiation.  */
3574     instantiate_decl (decl, /*defer_ok=*/true,
3575 		      /*expl_inst_class_mem_p=*/false);
3576 
3577   processing_template_decl = saved_processing_template_decl;
3578 }
3579 
3580 #include "gt-cp-decl2.h"
3581