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 	       && flag_visibility_ms_compat)
1735 	{
1736 	  /* Under -fvisibility-ms-compat, types are visible by default,
1737 	     even though their contents aren't.  */
1738 	  tree underlying_type = TREE_TYPE (DECL_NAME (decl));
1739 	  int underlying_vis = type_visibility (underlying_type);
1740 	  if (underlying_vis == VISIBILITY_ANON
1741 	      || CLASSTYPE_VISIBILITY_SPECIFIED (underlying_type))
1742 	    constrain_visibility (decl, underlying_vis);
1743 	  else
1744 	    DECL_VISIBILITY (decl) = VISIBILITY_DEFAULT;
1745 	}
1746       else if (TREE_CODE (decl) == VAR_DECL && DECL_TINFO_P (decl))
1747 	{
1748 	  /* tinfo visibility is based on the type it's for.  */
1749 	  constrain_visibility
1750 	    (decl, type_visibility (TREE_TYPE (DECL_NAME (decl))));
1751 	}
1752       else if (use_template)
1753 	/* Template instantiations and specializations get visibility based
1754 	   on their template unless they override it with an attribute.  */;
1755       else if (! DECL_VISIBILITY_SPECIFIED (decl))
1756 	{
1757 	  /* Set default visibility to whatever the user supplied with
1758 	     #pragma GCC visibility or a namespace visibility attribute.  */
1759 	  DECL_VISIBILITY (decl) = default_visibility;
1760 	  DECL_VISIBILITY_SPECIFIED (decl) = visibility_options.inpragma;
1761 	}
1762     }
1763 
1764   if (use_template)
1765     {
1766       /* If the specialization doesn't specify visibility, use the
1767 	 visibility from the template.  */
1768       tree tinfo = (TREE_CODE (decl) == TYPE_DECL
1769 		    ? TYPE_TEMPLATE_INFO (TREE_TYPE (decl))
1770 		    : DECL_TEMPLATE_INFO (decl));
1771       tree args = TI_ARGS (tinfo);
1772 
1773       if (args != error_mark_node)
1774 	{
1775 	  int depth = TMPL_ARGS_DEPTH (args);
1776 	  tree pattern = DECL_TEMPLATE_RESULT (TI_TEMPLATE (tinfo));
1777 
1778 	  if (!DECL_VISIBILITY_SPECIFIED (decl))
1779 	    {
1780 	      DECL_VISIBILITY (decl) = DECL_VISIBILITY (pattern);
1781 	      DECL_VISIBILITY_SPECIFIED (decl)
1782 		= DECL_VISIBILITY_SPECIFIED (pattern);
1783 	    }
1784 
1785 	  /* FIXME should TMPL_ARGS_DEPTH really return 1 for null input? */
1786 	  if (args && depth > template_class_depth (class_type))
1787 	    /* Limit visibility based on its template arguments.  */
1788 	    constrain_visibility_for_template (decl, args);
1789 	}
1790     }
1791 
1792   if (class_type)
1793     determine_visibility_from_class (decl, class_type);
1794 
1795   if (decl_anon_ns_mem_p (decl))
1796     /* Names in an anonymous namespace get internal linkage.
1797        This might change once we implement export.  */
1798     constrain_visibility (decl, VISIBILITY_ANON);
1799   else if (TREE_CODE (decl) != TYPE_DECL)
1800     {
1801       /* Propagate anonymity from type to decl.  */
1802       int tvis = type_visibility (TREE_TYPE (decl));
1803       if (tvis == VISIBILITY_ANON)
1804 	constrain_visibility (decl, tvis);
1805     }
1806 }
1807 
1808 /* By default, static data members and function members receive
1809    the visibility of their containing class.  */
1810 
1811 static void
determine_visibility_from_class(tree decl,tree class_type)1812 determine_visibility_from_class (tree decl, tree class_type)
1813 {
1814   if (visibility_options.inlines_hidden
1815       /* Don't do this for inline templates; specializations might not be
1816 	 inline, and we don't want them to inherit the hidden
1817 	 visibility.  We'll set it here for all inline instantiations.  */
1818       && !processing_template_decl
1819       && ! DECL_VISIBILITY_SPECIFIED (decl)
1820       && TREE_CODE (decl) == FUNCTION_DECL
1821       && DECL_DECLARED_INLINE_P (decl)
1822       && (! DECL_LANG_SPECIFIC (decl)
1823 	  || ! DECL_EXPLICIT_INSTANTIATION (decl)))
1824     DECL_VISIBILITY (decl) = VISIBILITY_HIDDEN;
1825   else if (!DECL_VISIBILITY_SPECIFIED (decl))
1826     {
1827       /* Default to the class visibility.  */
1828       DECL_VISIBILITY (decl) = CLASSTYPE_VISIBILITY (class_type);
1829       DECL_VISIBILITY_SPECIFIED (decl)
1830 	= CLASSTYPE_VISIBILITY_SPECIFIED (class_type);
1831     }
1832 
1833   /* Give the target a chance to override the visibility associated
1834      with DECL.  */
1835   if (TREE_CODE (decl) == VAR_DECL
1836       && (DECL_TINFO_P (decl)
1837 	  || (DECL_VTABLE_OR_VTT_P (decl)
1838 	      /* Construction virtual tables are not exported because
1839 		 they cannot be referred to from other object files;
1840 		 their name is not standardized by the ABI.  */
1841 	      && !DECL_CONSTRUCTION_VTABLE_P (decl)))
1842       && TREE_PUBLIC (decl)
1843       && !DECL_REALLY_EXTERN (decl)
1844       && !DECL_VISIBILITY_SPECIFIED (decl)
1845       && !CLASSTYPE_VISIBILITY_SPECIFIED (class_type))
1846     targetm.cxx.determine_class_data_visibility (decl);
1847 }
1848 
1849 /* Constrain the visibility of a class TYPE based on the visibility of its
1850    field types.  Warn if any fields require lesser visibility.  */
1851 
1852 void
constrain_class_visibility(tree type)1853 constrain_class_visibility (tree type)
1854 {
1855   tree binfo;
1856   tree t;
1857   int i;
1858 
1859   int vis = type_visibility (type);
1860 
1861   if (vis == VISIBILITY_ANON
1862       || DECL_IN_SYSTEM_HEADER (TYPE_MAIN_DECL (type)))
1863     return;
1864 
1865   /* Don't warn about visibility if the class has explicit visibility.  */
1866   if (CLASSTYPE_VISIBILITY_SPECIFIED (type))
1867     vis = VISIBILITY_INTERNAL;
1868 
1869   for (t = TYPE_FIELDS (type); t; t = TREE_CHAIN (t))
1870     if (TREE_CODE (t) == FIELD_DECL && TREE_TYPE (t) != error_mark_node)
1871       {
1872 	tree ftype = strip_array_types (TREE_TYPE (t));
1873 	int subvis = type_visibility (ftype);
1874 
1875 	if (subvis == VISIBILITY_ANON)
1876 	  {
1877 	    if (!in_main_input_context ())
1878 	      warning (0, "\
1879 %qT has a field %qD whose type uses the anonymous namespace",
1880 		   type, t);
1881 	  }
1882 	else if (IS_AGGR_TYPE (ftype)
1883 		 && vis < VISIBILITY_HIDDEN
1884 		 && subvis >= VISIBILITY_HIDDEN)
1885 	  warning (OPT_Wattributes, "\
1886 %qT declared with greater visibility than the type of its field %qD",
1887 		   type, t);
1888       }
1889 
1890   binfo = TYPE_BINFO (type);
1891   for (i = 0; BINFO_BASE_ITERATE (binfo, i, t); ++i)
1892     {
1893       int subvis = type_visibility (TREE_TYPE (t));
1894 
1895       if (subvis == VISIBILITY_ANON)
1896         {
1897 	  if (!in_main_input_context())
1898 	    warning (0, "\
1899 %qT has a base %qT whose type uses the anonymous namespace",
1900 		 type, TREE_TYPE (t));
1901 	}
1902       else if (vis < VISIBILITY_HIDDEN
1903 	       && subvis >= VISIBILITY_HIDDEN)
1904 	warning (OPT_Wattributes, "\
1905 %qT declared with greater visibility than its base %qT",
1906 		 type, TREE_TYPE (t));
1907     }
1908 }
1909 
1910 /* DECL is a FUNCTION_DECL or VAR_DECL.  If the object file linkage
1911    for DECL has not already been determined, do so now by setting
1912    DECL_EXTERNAL, DECL_COMDAT and other related flags.  Until this
1913    function is called entities with vague linkage whose definitions
1914    are available must have TREE_PUBLIC set.
1915 
1916    If this function decides to place DECL in COMDAT, it will set
1917    appropriate flags -- but will not clear DECL_EXTERNAL.  It is up to
1918    the caller to decide whether or not to clear DECL_EXTERNAL.  Some
1919    callers defer that decision until it is clear that DECL is actually
1920    required.  */
1921 
1922 void
import_export_decl(tree decl)1923 import_export_decl (tree decl)
1924 {
1925   int emit_p;
1926   bool comdat_p;
1927   bool import_p;
1928   tree class_type = NULL_TREE;
1929 
1930   if (DECL_INTERFACE_KNOWN (decl))
1931     return;
1932 
1933   /* We cannot determine what linkage to give to an entity with vague
1934      linkage until the end of the file.  For example, a virtual table
1935      for a class will be defined if and only if the key method is
1936      defined in this translation unit.  As a further example, consider
1937      that when compiling a translation unit that uses PCH file with
1938      "-frepo" it would be incorrect to make decisions about what
1939      entities to emit when building the PCH; those decisions must be
1940      delayed until the repository information has been processed.  */
1941   gcc_assert (at_eof);
1942   /* Object file linkage for explicit instantiations is handled in
1943      mark_decl_instantiated.  For static variables in functions with
1944      vague linkage, maybe_commonize_var is used.
1945 
1946      Therefore, the only declarations that should be provided to this
1947      function are those with external linkage that are:
1948 
1949      * implicit instantiations of function templates
1950 
1951      * inline function
1952 
1953      * implicit instantiations of static data members of class
1954        templates
1955 
1956      * virtual tables
1957 
1958      * typeinfo objects
1959 
1960      Furthermore, all entities that reach this point must have a
1961      definition available in this translation unit.
1962 
1963      The following assertions check these conditions.  */
1964   gcc_assert (TREE_CODE (decl) == FUNCTION_DECL
1965 	      || TREE_CODE (decl) == VAR_DECL);
1966   /* Any code that creates entities with TREE_PUBLIC cleared should
1967      also set DECL_INTERFACE_KNOWN.  */
1968   gcc_assert (TREE_PUBLIC (decl));
1969   if (TREE_CODE (decl) == FUNCTION_DECL)
1970     gcc_assert (DECL_IMPLICIT_INSTANTIATION (decl)
1971 		|| DECL_FRIEND_PSEUDO_TEMPLATE_INSTANTIATION (decl)
1972 		|| DECL_DECLARED_INLINE_P (decl));
1973   else
1974     gcc_assert (DECL_IMPLICIT_INSTANTIATION (decl)
1975 		|| DECL_VTABLE_OR_VTT_P (decl)
1976 		|| DECL_TINFO_P (decl));
1977   /* Check that a definition of DECL is available in this translation
1978      unit.  */
1979   gcc_assert (!DECL_REALLY_EXTERN (decl));
1980 
1981   /* Assume that DECL will not have COMDAT linkage.  */
1982   comdat_p = false;
1983   /* Assume that DECL will not be imported into this translation
1984      unit.  */
1985   import_p = false;
1986 
1987   /* See if the repository tells us whether or not to emit DECL in
1988      this translation unit.  */
1989   emit_p = repo_emit_p (decl);
1990   if (emit_p == 0)
1991     import_p = true;
1992   else if (emit_p == 1)
1993     {
1994       /* The repository indicates that this entity should be defined
1995 	 here.  Make sure the back end honors that request.  */
1996       if (TREE_CODE (decl) == VAR_DECL)
1997 	mark_needed (decl);
1998       else if (DECL_MAYBE_IN_CHARGE_CONSTRUCTOR_P (decl)
1999 	       || DECL_MAYBE_IN_CHARGE_DESTRUCTOR_P (decl))
2000 	{
2001 	  tree clone;
2002 	  FOR_EACH_CLONE (clone, decl)
2003 	    mark_needed (clone);
2004 	}
2005       else
2006 	mark_needed (decl);
2007       /* Output the definition as an ordinary strong definition.  */
2008       DECL_EXTERNAL (decl) = 0;
2009       DECL_INTERFACE_KNOWN (decl) = 1;
2010       return;
2011     }
2012 
2013   if (import_p)
2014     /* We have already decided what to do with this DECL; there is no
2015        need to check anything further.  */
2016     ;
2017   else if (TREE_CODE (decl) == VAR_DECL && DECL_VTABLE_OR_VTT_P (decl))
2018     {
2019       class_type = DECL_CONTEXT (decl);
2020       import_export_class (class_type);
2021       if (TYPE_FOR_JAVA (class_type))
2022 	import_p = true;
2023       else if (CLASSTYPE_INTERFACE_KNOWN (class_type)
2024 	       && CLASSTYPE_INTERFACE_ONLY (class_type))
2025 	import_p = true;
2026       else if ((!flag_weak || TARGET_WEAK_NOT_IN_ARCHIVE_TOC)
2027 	       && !CLASSTYPE_USE_TEMPLATE (class_type)
2028 	       && CLASSTYPE_KEY_METHOD (class_type)
2029 	       && !DECL_DECLARED_INLINE_P (CLASSTYPE_KEY_METHOD (class_type)))
2030 	/* The ABI requires that all virtual tables be emitted with
2031 	   COMDAT linkage.  However, on systems where COMDAT symbols
2032 	   don't show up in the table of contents for a static
2033 	   archive, or on systems without weak symbols (where we
2034 	   approximate COMDAT linkage by using internal linkage), the
2035 	   linker will report errors about undefined symbols because
2036 	   it will not see the virtual table definition.  Therefore,
2037 	   in the case that we know that the virtual table will be
2038 	   emitted in only one translation unit, we make the virtual
2039 	   table an ordinary definition with external linkage.  */
2040 	DECL_EXTERNAL (decl) = 0;
2041       else if (CLASSTYPE_INTERFACE_KNOWN (class_type))
2042 	{
2043 	  /* CLASS_TYPE is being exported from this translation unit,
2044 	     so DECL should be defined here.  */
2045 	  if (!flag_weak && CLASSTYPE_EXPLICIT_INSTANTIATION (class_type))
2046 	    /* If a class is declared in a header with the "extern
2047 	       template" extension, then it will not be instantiated,
2048 	       even in translation units that would normally require
2049 	       it.  Often such classes are explicitly instantiated in
2050 	       one translation unit.  Therefore, the explicit
2051 	       instantiation must be made visible to other translation
2052 	       units.  */
2053 	    DECL_EXTERNAL (decl) = 0;
2054 	  else
2055 	    {
2056 	      /* The generic C++ ABI says that class data is always
2057 		 COMDAT, even if there is a key function.  Some
2058 		 variants (e.g., the ARM EABI) says that class data
2059 		 only has COMDAT linkage if the class data might be
2060 		 emitted in more than one translation unit.  When the
2061 		 key method can be inline and is inline, we still have
2062 		 to arrange for comdat even though
2063 		 class_data_always_comdat is false.  */
2064 	      if (!CLASSTYPE_KEY_METHOD (class_type)
2065 		  || DECL_DECLARED_INLINE_P (CLASSTYPE_KEY_METHOD (class_type))
2066 		  || targetm.cxx.class_data_always_comdat ())
2067 		{
2068 		  /* The ABI requires COMDAT linkage.  Normally, we
2069 		     only emit COMDAT things when they are needed;
2070 		     make sure that we realize that this entity is
2071 		     indeed needed.  */
2072 		  comdat_p = true;
2073 		  mark_needed (decl);
2074 		}
2075 	    }
2076 	}
2077       else if (!flag_implicit_templates
2078 	       && CLASSTYPE_IMPLICIT_INSTANTIATION (class_type))
2079 	import_p = true;
2080       else
2081 	comdat_p = true;
2082     }
2083   else if (TREE_CODE (decl) == VAR_DECL && DECL_TINFO_P (decl))
2084     {
2085       tree type = TREE_TYPE (DECL_NAME (decl));
2086       if (CLASS_TYPE_P (type))
2087 	{
2088 	  class_type = type;
2089 	  import_export_class (type);
2090 	  if (CLASSTYPE_INTERFACE_KNOWN (type)
2091 	      && TYPE_POLYMORPHIC_P (type)
2092 	      && CLASSTYPE_INTERFACE_ONLY (type)
2093 	      /* If -fno-rtti was specified, then we cannot be sure
2094 		 that RTTI information will be emitted with the
2095 		 virtual table of the class, so we must emit it
2096 		 wherever it is used.  */
2097 	      && flag_rtti)
2098 	    import_p = true;
2099 	  else
2100 	    {
2101 	      if (CLASSTYPE_INTERFACE_KNOWN (type)
2102 		  && !CLASSTYPE_INTERFACE_ONLY (type))
2103 		{
2104 		  comdat_p = (targetm.cxx.class_data_always_comdat ()
2105 			      || (CLASSTYPE_KEY_METHOD (type)
2106 				  && DECL_DECLARED_INLINE_P (CLASSTYPE_KEY_METHOD (type))));
2107 		  mark_needed (decl);
2108 		  if (!flag_weak)
2109 		    {
2110 		      comdat_p = false;
2111 		      DECL_EXTERNAL (decl) = 0;
2112 		    }
2113 		}
2114 	      else
2115 		comdat_p = true;
2116 	    }
2117 	}
2118       else
2119 	comdat_p = true;
2120     }
2121   else if (DECL_TEMPLATE_INSTANTIATION (decl)
2122 	   || DECL_FRIEND_PSEUDO_TEMPLATE_INSTANTIATION (decl))
2123     {
2124       /* DECL is an implicit instantiation of a function or static
2125 	 data member.  */
2126       if (flag_implicit_templates
2127 	  || (flag_implicit_inline_templates
2128 	      && TREE_CODE (decl) == FUNCTION_DECL
2129 	      && DECL_DECLARED_INLINE_P (decl)))
2130 	comdat_p = true;
2131       else
2132 	/* If we are not implicitly generating templates, then mark
2133 	   this entity as undefined in this translation unit.  */
2134 	import_p = true;
2135     }
2136   else if (DECL_FUNCTION_MEMBER_P (decl))
2137     {
2138       if (!DECL_DECLARED_INLINE_P (decl))
2139 	{
2140 	  tree ctype = DECL_CONTEXT (decl);
2141 	  import_export_class (ctype);
2142 	  if (CLASSTYPE_INTERFACE_KNOWN (ctype))
2143 	    {
2144 	      DECL_NOT_REALLY_EXTERN (decl)
2145 		= ! (CLASSTYPE_INTERFACE_ONLY (ctype)
2146 		     || (DECL_DECLARED_INLINE_P (decl)
2147 			 && ! flag_implement_inlines
2148 			 && !DECL_VINDEX (decl)));
2149 
2150 	      if (!DECL_NOT_REALLY_EXTERN (decl))
2151 		DECL_EXTERNAL (decl) = 1;
2152 
2153 	      /* Always make artificials weak.  */
2154 	      if (DECL_ARTIFICIAL (decl) && flag_weak)
2155 		comdat_p = true;
2156 	      else
2157 		maybe_make_one_only (decl);
2158 	    }
2159 	}
2160       else
2161 	comdat_p = true;
2162     }
2163   else
2164     comdat_p = true;
2165 
2166   if (import_p)
2167     {
2168       /* If we are importing DECL into this translation unit, mark is
2169 	 an undefined here.  */
2170       DECL_EXTERNAL (decl) = 1;
2171       DECL_NOT_REALLY_EXTERN (decl) = 0;
2172     }
2173   else if (comdat_p)
2174     {
2175       /* If we decided to put DECL in COMDAT, mark it accordingly at
2176 	 this point.  */
2177       comdat_linkage (decl);
2178     }
2179 
2180   DECL_INTERFACE_KNOWN (decl) = 1;
2181 }
2182 
2183 /* Return an expression that performs the destruction of DECL, which
2184    must be a VAR_DECL whose type has a non-trivial destructor, or is
2185    an array whose (innermost) elements have a non-trivial destructor.  */
2186 
2187 tree
build_cleanup(tree decl)2188 build_cleanup (tree decl)
2189 {
2190   tree temp;
2191   tree type = TREE_TYPE (decl);
2192 
2193   /* This function should only be called for declarations that really
2194      require cleanups.  */
2195   gcc_assert (!TYPE_HAS_TRIVIAL_DESTRUCTOR (type));
2196 
2197   /* Treat all objects with destructors as used; the destructor may do
2198      something substantive.  */
2199   mark_used (decl);
2200 
2201   if (TREE_CODE (type) == ARRAY_TYPE)
2202     temp = decl;
2203   else
2204     {
2205       cxx_mark_addressable (decl);
2206       temp = build1 (ADDR_EXPR, build_pointer_type (type), decl);
2207     }
2208   temp = build_delete (TREE_TYPE (temp), temp,
2209 		       sfk_complete_destructor,
2210 		       LOOKUP_NORMAL|LOOKUP_NONVIRTUAL|LOOKUP_DESTRUCTOR, 0);
2211   return temp;
2212 }
2213 
2214 /* Returns the initialization guard variable for the variable DECL,
2215    which has static storage duration.  */
2216 
2217 tree
get_guard(tree decl)2218 get_guard (tree decl)
2219 {
2220   tree sname;
2221   tree guard;
2222 
2223   sname = mangle_guard_variable (decl);
2224   guard = IDENTIFIER_GLOBAL_VALUE (sname);
2225   if (! guard)
2226     {
2227       tree guard_type;
2228 
2229       /* We use a type that is big enough to contain a mutex as well
2230 	 as an integer counter.  */
2231       guard_type = targetm.cxx.guard_type ();
2232       guard = build_decl (VAR_DECL, sname, guard_type);
2233 
2234       /* The guard should have the same linkage as what it guards.  */
2235       TREE_PUBLIC (guard) = TREE_PUBLIC (decl);
2236       TREE_STATIC (guard) = TREE_STATIC (decl);
2237       DECL_COMMON (guard) = DECL_COMMON (decl);
2238       DECL_ONE_ONLY (guard) = DECL_ONE_ONLY (decl);
2239       if (TREE_PUBLIC (decl))
2240 	DECL_WEAK (guard) = DECL_WEAK (decl);
2241 
2242       DECL_ARTIFICIAL (guard) = 1;
2243       DECL_IGNORED_P (guard) = 1;
2244       TREE_USED (guard) = 1;
2245       pushdecl_top_level_and_finish (guard, NULL_TREE);
2246     }
2247   return guard;
2248 }
2249 
2250 /* Return those bits of the GUARD variable that should be set when the
2251    guarded entity is actually initialized.  */
2252 
2253 static tree
get_guard_bits(tree guard)2254 get_guard_bits (tree guard)
2255 {
2256   if (!targetm.cxx.guard_mask_bit ())
2257     {
2258       /* We only set the first byte of the guard, in order to leave room
2259 	 for a mutex in the high-order bits.  */
2260       guard = build1 (ADDR_EXPR,
2261 		      build_pointer_type (TREE_TYPE (guard)),
2262 		      guard);
2263       guard = build1 (NOP_EXPR,
2264 		      build_pointer_type (char_type_node),
2265 		      guard);
2266       guard = build1 (INDIRECT_REF, char_type_node, guard);
2267     }
2268 
2269   return guard;
2270 }
2271 
2272 /* Return an expression which determines whether or not the GUARD
2273    variable has already been initialized.  */
2274 
2275 tree
get_guard_cond(tree guard)2276 get_guard_cond (tree guard)
2277 {
2278   tree guard_value;
2279 
2280   /* Check to see if the GUARD is zero.  */
2281   guard = get_guard_bits (guard);
2282 
2283   /* Mask off all but the low bit.  */
2284   if (targetm.cxx.guard_mask_bit ())
2285     {
2286       guard_value = integer_one_node;
2287       if (!same_type_p (TREE_TYPE (guard_value), TREE_TYPE (guard)))
2288 	guard_value = convert (TREE_TYPE (guard), guard_value);
2289 	guard = cp_build_binary_op (BIT_AND_EXPR, guard, guard_value);
2290     }
2291 
2292   guard_value = integer_zero_node;
2293   if (!same_type_p (TREE_TYPE (guard_value), TREE_TYPE (guard)))
2294     guard_value = convert (TREE_TYPE (guard), guard_value);
2295   return cp_build_binary_op (EQ_EXPR, guard, guard_value);
2296 }
2297 
2298 /* Return an expression which sets the GUARD variable, indicating that
2299    the variable being guarded has been initialized.  */
2300 
2301 tree
set_guard(tree guard)2302 set_guard (tree guard)
2303 {
2304   tree guard_init;
2305 
2306   /* Set the GUARD to one.  */
2307   guard = get_guard_bits (guard);
2308   guard_init = integer_one_node;
2309   if (!same_type_p (TREE_TYPE (guard_init), TREE_TYPE (guard)))
2310     guard_init = convert (TREE_TYPE (guard), guard_init);
2311   return build_modify_expr (guard, NOP_EXPR, guard_init);
2312 }
2313 
2314 /* Start the process of running a particular set of global constructors
2315    or destructors.  Subroutine of do_[cd]tors.  */
2316 
2317 static tree
start_objects(int method_type,int initp)2318 start_objects (int method_type, int initp)
2319 {
2320   tree body;
2321   tree fndecl;
2322   char type[10];
2323 
2324   /* Make ctor or dtor function.  METHOD_TYPE may be 'I' or 'D'.  */
2325 
2326   if (initp != DEFAULT_INIT_PRIORITY)
2327     {
2328       char joiner;
2329 
2330 #ifdef JOINER
2331       joiner = JOINER;
2332 #else
2333       joiner = '_';
2334 #endif
2335 
2336       sprintf (type, "%c%c%.5u", method_type, joiner, initp);
2337     }
2338   else
2339     sprintf (type, "%c", method_type);
2340 
2341   fndecl = build_lang_decl (FUNCTION_DECL,
2342 			    get_file_function_name_long (type),
2343 			    build_function_type (void_type_node,
2344 						 void_list_node));
2345   start_preparsed_function (fndecl, /*attrs=*/NULL_TREE, SF_PRE_PARSED);
2346 
2347   /* It can be a static function as long as collect2 does not have
2348      to scan the object file to find its ctor/dtor routine.  */
2349   TREE_PUBLIC (current_function_decl) = ! targetm.have_ctors_dtors;
2350 
2351   /* Mark this declaration as used to avoid spurious warnings.  */
2352   TREE_USED (current_function_decl) = 1;
2353 
2354   /* Mark this function as a global constructor or destructor.  */
2355   if (method_type == 'I')
2356     DECL_GLOBAL_CTOR_P (current_function_decl) = 1;
2357   else
2358     DECL_GLOBAL_DTOR_P (current_function_decl) = 1;
2359   DECL_LANG_SPECIFIC (current_function_decl)->decl_flags.u2sel = 1;
2360 
2361   body = begin_compound_stmt (BCS_FN_BODY);
2362 
2363   /* We cannot allow these functions to be elided, even if they do not
2364      have external linkage.  And, there's no point in deferring
2365      compilation of these functions; they're all going to have to be
2366      out anyhow.  */
2367   DECL_INLINE (current_function_decl) = 0;
2368   DECL_UNINLINABLE (current_function_decl) = 1;
2369 
2370   return body;
2371 }
2372 
2373 /* Finish the process of running a particular set of global constructors
2374    or destructors.  Subroutine of do_[cd]tors.  */
2375 
2376 static void
finish_objects(int method_type,int initp,tree body)2377 finish_objects (int method_type, int initp, tree body)
2378 {
2379   tree fn;
2380 
2381   /* Finish up.  */
2382   finish_compound_stmt (body);
2383   fn = finish_function (0);
2384   expand_or_defer_fn (fn);
2385 
2386   /* When only doing semantic analysis, and no RTL generation, we
2387      can't call functions that directly emit assembly code; there is
2388      no assembly file in which to put the code.  */
2389   if (flag_syntax_only)
2390     return;
2391 
2392   if (targetm.have_ctors_dtors)
2393     {
2394       rtx fnsym = XEXP (DECL_RTL (fn), 0);
2395       cgraph_mark_needed_node (cgraph_node (fn));
2396       if (method_type == 'I')
2397 	(* targetm.asm_out.constructor) (fnsym, initp);
2398       else
2399 	(* targetm.asm_out.destructor) (fnsym, initp);
2400     }
2401 }
2402 
2403 /* The names of the parameters to the function created to handle
2404    initializations and destructions for objects with static storage
2405    duration.  */
2406 #define INITIALIZE_P_IDENTIFIER "__initialize_p"
2407 #define PRIORITY_IDENTIFIER "__priority"
2408 
2409 /* The name of the function we create to handle initializations and
2410    destructions for objects with static storage duration.  */
2411 #define SSDF_IDENTIFIER "__static_initialization_and_destruction"
2412 
2413 /* The declaration for the __INITIALIZE_P argument.  */
2414 static GTY(()) tree initialize_p_decl;
2415 
2416 /* The declaration for the __PRIORITY argument.  */
2417 static GTY(()) tree priority_decl;
2418 
2419 /* The declaration for the static storage duration function.  */
2420 static GTY(()) tree ssdf_decl;
2421 
2422 /* All the static storage duration functions created in this
2423    translation unit.  */
2424 static GTY(()) VEC(tree,gc) *ssdf_decls;
2425 
2426 /* A map from priority levels to information about that priority
2427    level.  There may be many such levels, so efficient lookup is
2428    important.  */
2429 static splay_tree priority_info_map;
2430 
2431 /* Begins the generation of the function that will handle all
2432    initialization and destruction of objects with static storage
2433    duration.  The function generated takes two parameters of type
2434    `int': __INITIALIZE_P and __PRIORITY.  If __INITIALIZE_P is
2435    nonzero, it performs initializations.  Otherwise, it performs
2436    destructions.  It only performs those initializations or
2437    destructions with the indicated __PRIORITY.  The generated function
2438    returns no value.
2439 
2440    It is assumed that this function will only be called once per
2441    translation unit.  */
2442 
2443 static tree
start_static_storage_duration_function(unsigned count)2444 start_static_storage_duration_function (unsigned count)
2445 {
2446   tree parm_types;
2447   tree type;
2448   tree body;
2449   char id[sizeof (SSDF_IDENTIFIER) + 1 /* '\0' */ + 32];
2450 
2451   /* Create the identifier for this function.  It will be of the form
2452      SSDF_IDENTIFIER_<number>.  */
2453   sprintf (id, "%s_%u", SSDF_IDENTIFIER, count);
2454 
2455   /* Create the parameters.  */
2456   parm_types = void_list_node;
2457   parm_types = tree_cons (NULL_TREE, integer_type_node, parm_types);
2458   parm_types = tree_cons (NULL_TREE, integer_type_node, parm_types);
2459   type = build_function_type (void_type_node, parm_types);
2460 
2461   /* Create the FUNCTION_DECL itself.  */
2462   ssdf_decl = build_lang_decl (FUNCTION_DECL,
2463 			       get_identifier (id),
2464 			       type);
2465   TREE_PUBLIC (ssdf_decl) = 0;
2466   DECL_ARTIFICIAL (ssdf_decl) = 1;
2467 
2468   /* Put this function in the list of functions to be called from the
2469      static constructors and destructors.  */
2470   if (!ssdf_decls)
2471     {
2472       ssdf_decls = VEC_alloc (tree, gc, 32);
2473 
2474       /* Take this opportunity to initialize the map from priority
2475 	 numbers to information about that priority level.  */
2476       priority_info_map = splay_tree_new (splay_tree_compare_ints,
2477 					  /*delete_key_fn=*/0,
2478 					  /*delete_value_fn=*/
2479 					  (splay_tree_delete_value_fn) &free);
2480 
2481       /* We always need to generate functions for the
2482 	 DEFAULT_INIT_PRIORITY so enter it now.  That way when we walk
2483 	 priorities later, we'll be sure to find the
2484 	 DEFAULT_INIT_PRIORITY.  */
2485       get_priority_info (DEFAULT_INIT_PRIORITY);
2486     }
2487 
2488   VEC_safe_push (tree, gc, ssdf_decls, ssdf_decl);
2489 
2490   /* Create the argument list.  */
2491   initialize_p_decl = cp_build_parm_decl
2492     (get_identifier (INITIALIZE_P_IDENTIFIER), integer_type_node);
2493   DECL_CONTEXT (initialize_p_decl) = ssdf_decl;
2494   TREE_USED (initialize_p_decl) = 1;
2495   priority_decl = cp_build_parm_decl
2496     (get_identifier (PRIORITY_IDENTIFIER), integer_type_node);
2497   DECL_CONTEXT (priority_decl) = ssdf_decl;
2498   TREE_USED (priority_decl) = 1;
2499 
2500   TREE_CHAIN (initialize_p_decl) = priority_decl;
2501   DECL_ARGUMENTS (ssdf_decl) = initialize_p_decl;
2502 
2503   /* Put the function in the global scope.  */
2504   pushdecl (ssdf_decl);
2505 
2506   /* Start the function itself.  This is equivalent to declaring the
2507      function as:
2508 
2509        static void __ssdf (int __initialize_p, init __priority_p);
2510 
2511      It is static because we only need to call this function from the
2512      various constructor and destructor functions for this module.  */
2513   start_preparsed_function (ssdf_decl,
2514 			    /*attrs=*/NULL_TREE,
2515 			    SF_PRE_PARSED);
2516 
2517   /* Set up the scope of the outermost block in the function.  */
2518   body = begin_compound_stmt (BCS_FN_BODY);
2519 
2520   /* This function must not be deferred because we are depending on
2521      its compilation to tell us what is TREE_SYMBOL_REFERENCED.  */
2522   DECL_INLINE (ssdf_decl) = 0;
2523   DECL_UNINLINABLE (ssdf_decl) = 1;
2524 
2525   return body;
2526 }
2527 
2528 /* Finish the generation of the function which performs initialization
2529    and destruction of objects with static storage duration.  After
2530    this point, no more such objects can be created.  */
2531 
2532 static void
finish_static_storage_duration_function(tree body)2533 finish_static_storage_duration_function (tree body)
2534 {
2535   /* Close out the function.  */
2536   finish_compound_stmt (body);
2537   expand_or_defer_fn (finish_function (0));
2538 }
2539 
2540 /* Return the information about the indicated PRIORITY level.  If no
2541    code to handle this level has yet been generated, generate the
2542    appropriate prologue.  */
2543 
2544 static priority_info
get_priority_info(int priority)2545 get_priority_info (int priority)
2546 {
2547   priority_info pi;
2548   splay_tree_node n;
2549 
2550   n = splay_tree_lookup (priority_info_map,
2551 			 (splay_tree_key) priority);
2552   if (!n)
2553     {
2554       /* Create a new priority information structure, and insert it
2555 	 into the map.  */
2556       pi = XNEW (struct priority_info_s);
2557       pi->initializations_p = 0;
2558       pi->destructions_p = 0;
2559       splay_tree_insert (priority_info_map,
2560 			 (splay_tree_key) priority,
2561 			 (splay_tree_value) pi);
2562     }
2563   else
2564     pi = (priority_info) n->value;
2565 
2566   return pi;
2567 }
2568 
2569 /* The effective initialization priority of a DECL.  */
2570 
2571 #define DECL_EFFECTIVE_INIT_PRIORITY(decl)				      \
2572 	((!DECL_HAS_INIT_PRIORITY_P (decl) || DECL_INIT_PRIORITY (decl) == 0) \
2573 	 ? DEFAULT_INIT_PRIORITY : DECL_INIT_PRIORITY (decl))
2574 
2575 /* Whether a DECL needs a guard to protect it against multiple
2576    initialization.  */
2577 
2578 #define NEEDS_GUARD_P(decl) (TREE_PUBLIC (decl) && (DECL_COMMON (decl)      \
2579 						    || DECL_ONE_ONLY (decl) \
2580 						    || DECL_WEAK (decl)))
2581 
2582 /* Set up to handle the initialization or destruction of DECL.  If
2583    INITP is nonzero, we are initializing the variable.  Otherwise, we
2584    are destroying it.  */
2585 
2586 static void
one_static_initialization_or_destruction(tree decl,tree init,bool initp)2587 one_static_initialization_or_destruction (tree decl, tree init, bool initp)
2588 {
2589   tree guard_if_stmt = NULL_TREE;
2590   tree guard;
2591 
2592   /* If we are supposed to destruct and there's a trivial destructor,
2593      nothing has to be done.  */
2594   if (!initp
2595       && TYPE_HAS_TRIVIAL_DESTRUCTOR (TREE_TYPE (decl)))
2596     return;
2597 
2598   /* Trick the compiler into thinking we are at the file and line
2599      where DECL was declared so that error-messages make sense, and so
2600      that the debugger will show somewhat sensible file and line
2601      information.  */
2602   input_location = DECL_SOURCE_LOCATION (decl);
2603 
2604   /* Because of:
2605 
2606        [class.access.spec]
2607 
2608        Access control for implicit calls to the constructors,
2609        the conversion functions, or the destructor called to
2610        create and destroy a static data member is performed as
2611        if these calls appeared in the scope of the member's
2612        class.
2613 
2614      we pretend we are in a static member function of the class of
2615      which the DECL is a member.  */
2616   if (member_p (decl))
2617     {
2618       DECL_CONTEXT (current_function_decl) = DECL_CONTEXT (decl);
2619       DECL_STATIC_FUNCTION_P (current_function_decl) = 1;
2620     }
2621 
2622   /* Assume we don't need a guard.  */
2623   guard = NULL_TREE;
2624   /* We need a guard if this is an object with external linkage that
2625      might be initialized in more than one place.  (For example, a
2626      static data member of a template, when the data member requires
2627      construction.)  */
2628   if (NEEDS_GUARD_P (decl))
2629     {
2630       tree guard_cond;
2631 
2632       guard = get_guard (decl);
2633 
2634       /* When using __cxa_atexit, we just check the GUARD as we would
2635 	 for a local static.  */
2636       if (flag_use_cxa_atexit)
2637 	{
2638 	  /* When using __cxa_atexit, we never try to destroy
2639 	     anything from a static destructor.  */
2640 	  gcc_assert (initp);
2641 	  guard_cond = get_guard_cond (guard);
2642 	}
2643       /* If we don't have __cxa_atexit, then we will be running
2644 	 destructors from .fini sections, or their equivalents.  So,
2645 	 we need to know how many times we've tried to initialize this
2646 	 object.  We do initializations only if the GUARD is zero,
2647 	 i.e., if we are the first to initialize the variable.  We do
2648 	 destructions only if the GUARD is one, i.e., if we are the
2649 	 last to destroy the variable.  */
2650       else if (initp)
2651 	guard_cond
2652 	  = cp_build_binary_op (EQ_EXPR,
2653 				build_unary_op (PREINCREMENT_EXPR,
2654 						guard,
2655 						/*noconvert=*/1),
2656 				integer_one_node);
2657       else
2658 	guard_cond
2659 	  = cp_build_binary_op (EQ_EXPR,
2660 				build_unary_op (PREDECREMENT_EXPR,
2661 						guard,
2662 						/*noconvert=*/1),
2663 				integer_zero_node);
2664 
2665       guard_if_stmt = begin_if_stmt ();
2666       finish_if_stmt_cond (guard_cond, guard_if_stmt);
2667     }
2668 
2669 
2670   /* If we're using __cxa_atexit, we have not already set the GUARD,
2671      so we must do so now.  */
2672   if (guard && initp && flag_use_cxa_atexit)
2673     finish_expr_stmt (set_guard (guard));
2674 
2675   /* Perform the initialization or destruction.  */
2676   if (initp)
2677     {
2678       if (init)
2679 	finish_expr_stmt (init);
2680 
2681       /* If we're using __cxa_atexit, register a function that calls the
2682 	 destructor for the object.  */
2683       if (flag_use_cxa_atexit)
2684 	finish_expr_stmt (register_dtor_fn (decl));
2685     }
2686   else
2687     finish_expr_stmt (build_cleanup (decl));
2688 
2689   /* Finish the guard if-stmt, if necessary.  */
2690   if (guard)
2691     {
2692       finish_then_clause (guard_if_stmt);
2693       finish_if_stmt (guard_if_stmt);
2694     }
2695 
2696   /* Now that we're done with DECL we don't need to pretend to be a
2697      member of its class any longer.  */
2698   DECL_CONTEXT (current_function_decl) = NULL_TREE;
2699   DECL_STATIC_FUNCTION_P (current_function_decl) = 0;
2700 }
2701 
2702 /* Generate code to do the initialization or destruction of the decls in VARS,
2703    a TREE_LIST of VAR_DECL with static storage duration.
2704    Whether initialization or destruction is performed is specified by INITP.  */
2705 
2706 static void
do_static_initialization_or_destruction(tree vars,bool initp)2707 do_static_initialization_or_destruction (tree vars, bool initp)
2708 {
2709   tree node, init_if_stmt, cond;
2710 
2711   /* Build the outer if-stmt to check for initialization or destruction.  */
2712   init_if_stmt = begin_if_stmt ();
2713   cond = initp ? integer_one_node : integer_zero_node;
2714   cond = cp_build_binary_op (EQ_EXPR,
2715 				  initialize_p_decl,
2716 				  cond);
2717   finish_if_stmt_cond (cond, init_if_stmt);
2718 
2719   node = vars;
2720   do {
2721     tree decl = TREE_VALUE (node);
2722     tree priority_if_stmt;
2723     int priority;
2724     priority_info pi;
2725 
2726     /* If we don't need a destructor, there's nothing to do.  Avoid
2727        creating a possibly empty if-stmt.  */
2728     if (!initp && TYPE_HAS_TRIVIAL_DESTRUCTOR (TREE_TYPE (decl)))
2729       {
2730 	node = TREE_CHAIN (node);
2731 	continue;
2732       }
2733 
2734     /* Remember that we had an initialization or finalization at this
2735        priority.  */
2736     priority = DECL_EFFECTIVE_INIT_PRIORITY (decl);
2737     pi = get_priority_info (priority);
2738     if (initp)
2739       pi->initializations_p = 1;
2740     else
2741       pi->destructions_p = 1;
2742 
2743     /* Conditionalize this initialization on being in the right priority
2744        and being initializing/finalizing appropriately.  */
2745     priority_if_stmt = begin_if_stmt ();
2746     cond = cp_build_binary_op (EQ_EXPR,
2747 			       priority_decl,
2748 			       build_int_cst (NULL_TREE, priority));
2749     finish_if_stmt_cond (cond, priority_if_stmt);
2750 
2751     /* Process initializers with same priority.  */
2752     for (; node
2753 	   && DECL_EFFECTIVE_INIT_PRIORITY (TREE_VALUE (node)) == priority;
2754 	 node = TREE_CHAIN (node))
2755       /* Do one initialization or destruction.  */
2756       one_static_initialization_or_destruction (TREE_VALUE (node),
2757 						TREE_PURPOSE (node), initp);
2758 
2759     /* Finish up the priority if-stmt body.  */
2760     finish_then_clause (priority_if_stmt);
2761     finish_if_stmt (priority_if_stmt);
2762 
2763   } while (node);
2764 
2765   /* Finish up the init/destruct if-stmt body.  */
2766   finish_then_clause (init_if_stmt);
2767   finish_if_stmt (init_if_stmt);
2768 }
2769 
2770 /* VARS is a list of variables with static storage duration which may
2771    need initialization and/or finalization.  Remove those variables
2772    that don't really need to be initialized or finalized, and return
2773    the resulting list.  The order in which the variables appear in
2774    VARS is in reverse order of the order in which they should actually
2775    be initialized.  The list we return is in the unreversed order;
2776    i.e., the first variable should be initialized first.  */
2777 
2778 static tree
prune_vars_needing_no_initialization(tree * vars)2779 prune_vars_needing_no_initialization (tree *vars)
2780 {
2781   tree *var = vars;
2782   tree result = NULL_TREE;
2783 
2784   while (*var)
2785     {
2786       tree t = *var;
2787       tree decl = TREE_VALUE (t);
2788       tree init = TREE_PURPOSE (t);
2789 
2790       /* Deal gracefully with error.  */
2791       if (decl == error_mark_node)
2792 	{
2793 	  var = &TREE_CHAIN (t);
2794 	  continue;
2795 	}
2796 
2797       /* The only things that can be initialized are variables.  */
2798       gcc_assert (TREE_CODE (decl) == VAR_DECL);
2799 
2800       /* If this object is not defined, we don't need to do anything
2801 	 here.  */
2802       if (DECL_EXTERNAL (decl))
2803 	{
2804 	  var = &TREE_CHAIN (t);
2805 	  continue;
2806 	}
2807 
2808       /* Also, if the initializer already contains errors, we can bail
2809 	 out now.  */
2810       if (init && TREE_CODE (init) == TREE_LIST
2811 	  && value_member (error_mark_node, init))
2812 	{
2813 	  var = &TREE_CHAIN (t);
2814 	  continue;
2815 	}
2816 
2817       /* This variable is going to need initialization and/or
2818 	 finalization, so we add it to the list.  */
2819       *var = TREE_CHAIN (t);
2820       TREE_CHAIN (t) = result;
2821       result = t;
2822     }
2823 
2824   return result;
2825 }
2826 
2827 /* Make sure we have told the back end about all the variables in
2828    VARS.  */
2829 
2830 static void
write_out_vars(tree vars)2831 write_out_vars (tree vars)
2832 {
2833   tree v;
2834 
2835   for (v = vars; v; v = TREE_CHAIN (v))
2836     {
2837       tree var = TREE_VALUE (v);
2838       if (!var_finalized_p (var))
2839 	{
2840 	  import_export_decl (var);
2841 	  rest_of_decl_compilation (var, 1, 1);
2842 	}
2843     }
2844 }
2845 
2846 /* Generate a static constructor (if CONSTRUCTOR_P) or destructor
2847    (otherwise) that will initialize all gobal objects with static
2848    storage duration having the indicated PRIORITY.  */
2849 
2850 static void
generate_ctor_or_dtor_function(bool constructor_p,int priority,location_t * locus)2851 generate_ctor_or_dtor_function (bool constructor_p, int priority,
2852 				location_t *locus)
2853 {
2854   char function_key;
2855   tree arguments;
2856   tree fndecl;
2857   tree body;
2858   size_t i;
2859 
2860   input_location = *locus;
2861 #ifdef USE_MAPPED_LOCATION
2862   /* ??? */
2863 #else
2864   locus->line++;
2865 #endif
2866 
2867   /* We use `I' to indicate initialization and `D' to indicate
2868      destruction.  */
2869   function_key = constructor_p ? 'I' : 'D';
2870 
2871   /* We emit the function lazily, to avoid generating empty
2872      global constructors and destructors.  */
2873   body = NULL_TREE;
2874 
2875   /* For Objective-C++, we may need to initialize metadata found in this module.
2876      This must be done _before_ any other static initializations.  */
2877   if (c_dialect_objc () && (priority == DEFAULT_INIT_PRIORITY)
2878       && constructor_p && objc_static_init_needed_p ())
2879     {
2880       body = start_objects (function_key, priority);
2881       static_ctors = objc_generate_static_init_call (static_ctors);
2882     }
2883 
2884   /* Call the static storage duration function with appropriate
2885      arguments.  */
2886   for (i = 0; VEC_iterate (tree, ssdf_decls, i, fndecl); ++i)
2887     {
2888       /* Calls to pure or const functions will expand to nothing.  */
2889       if (! (flags_from_decl_or_type (fndecl) & (ECF_CONST | ECF_PURE)))
2890 	{
2891 	  if (! body)
2892 	    body = start_objects (function_key, priority);
2893 
2894 	  arguments = tree_cons (NULL_TREE,
2895 				 build_int_cst (NULL_TREE, priority),
2896 				 NULL_TREE);
2897 	  arguments = tree_cons (NULL_TREE,
2898 				 build_int_cst (NULL_TREE, constructor_p),
2899 				 arguments);
2900 	  finish_expr_stmt (build_function_call (fndecl, arguments));
2901 	}
2902     }
2903 
2904   /* If we're generating code for the DEFAULT_INIT_PRIORITY, throw in
2905      calls to any functions marked with attributes indicating that
2906      they should be called at initialization- or destruction-time.  */
2907   if (priority == DEFAULT_INIT_PRIORITY)
2908     {
2909       tree fns;
2910 
2911       for (fns = constructor_p ? static_ctors : static_dtors;
2912 	   fns;
2913 	   fns = TREE_CHAIN (fns))
2914 	{
2915 	  fndecl = TREE_VALUE (fns);
2916 
2917 	  /* Calls to pure/const functions will expand to nothing.  */
2918 	  if (! (flags_from_decl_or_type (fndecl) & (ECF_CONST | ECF_PURE)))
2919 	    {
2920 	      if (! body)
2921 		body = start_objects (function_key, priority);
2922 	      finish_expr_stmt (build_function_call (fndecl, NULL_TREE));
2923 	    }
2924 	}
2925     }
2926 
2927   /* Close out the function.  */
2928   if (body)
2929     finish_objects (function_key, priority, body);
2930 }
2931 
2932 /* Generate constructor and destructor functions for the priority
2933    indicated by N.  */
2934 
2935 static int
generate_ctor_and_dtor_functions_for_priority(splay_tree_node n,void * data)2936 generate_ctor_and_dtor_functions_for_priority (splay_tree_node n, void * data)
2937 {
2938   location_t *locus = (location_t *) data;
2939   int priority = (int) n->key;
2940   priority_info pi = (priority_info) n->value;
2941 
2942   /* Generate the functions themselves, but only if they are really
2943      needed.  */
2944   if (pi->initializations_p
2945       || (priority == DEFAULT_INIT_PRIORITY && static_ctors))
2946     generate_ctor_or_dtor_function (/*constructor_p=*/true, priority, locus);
2947   if (pi->destructions_p
2948       || (priority == DEFAULT_INIT_PRIORITY && static_dtors))
2949     generate_ctor_or_dtor_function (/*constructor_p=*/false, priority, locus);
2950 
2951   /* Keep iterating.  */
2952   return 0;
2953 }
2954 
2955 /* Called via LANGHOOK_CALLGRAPH_ANALYZE_EXPR.  It is supposed to mark
2956    decls referenced from frontend specific constructs; it will be called
2957    only for language-specific tree nodes.
2958 
2959    Here we must deal with member pointers.  */
2960 
2961 tree
cxx_callgraph_analyze_expr(tree * tp,int * walk_subtrees ATTRIBUTE_UNUSED,tree from ATTRIBUTE_UNUSED)2962 cxx_callgraph_analyze_expr (tree *tp, int *walk_subtrees ATTRIBUTE_UNUSED,
2963 			    tree from ATTRIBUTE_UNUSED)
2964 {
2965   tree t = *tp;
2966 
2967   switch (TREE_CODE (t))
2968     {
2969     case PTRMEM_CST:
2970       if (TYPE_PTRMEMFUNC_P (TREE_TYPE (t)))
2971 	cgraph_mark_needed_node (cgraph_node (PTRMEM_CST_MEMBER (t)));
2972       break;
2973     case BASELINK:
2974       if (TREE_CODE (BASELINK_FUNCTIONS (t)) == FUNCTION_DECL)
2975 	cgraph_mark_needed_node (cgraph_node (BASELINK_FUNCTIONS (t)));
2976       break;
2977     case VAR_DECL:
2978       if (DECL_VTABLE_OR_VTT_P (t))
2979 	{
2980 	  /* The ABI requires that all virtual tables be emitted
2981 	     whenever one of them is.  */
2982 	  tree vtbl;
2983 	  for (vtbl = CLASSTYPE_VTABLES (DECL_CONTEXT (t));
2984 	       vtbl;
2985 	       vtbl = TREE_CHAIN (vtbl))
2986 	    mark_decl_referenced (vtbl);
2987 	}
2988       else if (DECL_CONTEXT (t)
2989 	       && TREE_CODE (DECL_CONTEXT (t)) == FUNCTION_DECL)
2990 	/* If we need a static variable in a function, then we
2991 	   need the containing function.  */
2992 	mark_decl_referenced (DECL_CONTEXT (t));
2993       break;
2994     default:
2995       break;
2996     }
2997 
2998   return NULL;
2999 }
3000 
3001 /* Java requires that we be able to reference a local address for a
3002    method, and not be confused by PLT entries.  If hidden aliases are
3003    supported, emit one for each java function that we've emitted.  */
3004 
3005 static void
build_java_method_aliases(void)3006 build_java_method_aliases (void)
3007 {
3008   struct cgraph_node *node;
3009 
3010 #ifndef HAVE_GAS_HIDDEN
3011   return;
3012 #endif
3013 
3014   for (node = cgraph_nodes; node ; node = node->next)
3015     {
3016       tree fndecl = node->decl;
3017 
3018       if (TREE_ASM_WRITTEN (fndecl)
3019 	  && DECL_CONTEXT (fndecl)
3020 	  && TYPE_P (DECL_CONTEXT (fndecl))
3021 	  && TYPE_FOR_JAVA (DECL_CONTEXT (fndecl))
3022 	  && TARGET_USE_LOCAL_THUNK_ALIAS_P (fndecl))
3023 	{
3024 	  /* Mangle the name in a predictable way; we need to reference
3025 	     this from a java compiled object file.  */
3026 	  tree oid, nid, alias;
3027 	  const char *oname;
3028 	  char *nname;
3029 
3030 	  oid = DECL_ASSEMBLER_NAME (fndecl);
3031 	  oname = IDENTIFIER_POINTER (oid);
3032 	  gcc_assert (oname[0] == '_' && oname[1] == 'Z');
3033 	  nname = ACONCAT (("_ZGA", oname+2, NULL));
3034 	  nid = get_identifier (nname);
3035 
3036 	  alias = make_alias_for (fndecl, nid);
3037 	  TREE_PUBLIC (alias) = 1;
3038 	  DECL_VISIBILITY (alias) = VISIBILITY_HIDDEN;
3039 
3040 	  assemble_alias (alias, oid);
3041 	}
3042     }
3043 }
3044 
3045 /* This routine is called from the last rule in yyparse ().
3046    Its job is to create all the code needed to initialize and
3047    destroy the global aggregates.  We do the destruction
3048    first, since that way we only need to reverse the decls once.  */
3049 
3050 void
cp_finish_file(void)3051 cp_finish_file (void)
3052 {
3053   tree vars;
3054   bool reconsider;
3055   size_t i;
3056   location_t locus;
3057   unsigned ssdf_count = 0;
3058   int retries = 0;
3059   tree decl;
3060 
3061   locus = input_location;
3062   at_eof = 1;
3063 
3064   /* Bad parse errors.  Just forget about it.  */
3065   if (! global_bindings_p () || current_class_type || decl_namespace_list)
3066     return;
3067 
3068   if (pch_file)
3069     c_common_write_pch ();
3070 
3071 #ifdef USE_MAPPED_LOCATION
3072   /* FIXME - huh? */
3073 #else
3074   /* Otherwise, GDB can get confused, because in only knows
3075      about source for LINENO-1 lines.  */
3076   input_line -= 1;
3077 #endif
3078 
3079   /* We now have to write out all the stuff we put off writing out.
3080      These include:
3081 
3082        o Template specializations that we have not yet instantiated,
3083 	 but which are needed.
3084        o Initialization and destruction for non-local objects with
3085 	 static storage duration.  (Local objects with static storage
3086 	 duration are initialized when their scope is first entered,
3087 	 and are cleaned up via atexit.)
3088        o Virtual function tables.
3089 
3090      All of these may cause others to be needed.  For example,
3091      instantiating one function may cause another to be needed, and
3092      generating the initializer for an object may cause templates to be
3093      instantiated, etc., etc.  */
3094 
3095   timevar_push (TV_VARCONST);
3096 
3097   emit_support_tinfos ();
3098 
3099   do
3100     {
3101       tree t;
3102       tree decl;
3103 
3104       reconsider = false;
3105 
3106       /* If there are templates that we've put off instantiating, do
3107 	 them now.  */
3108       instantiate_pending_templates (retries);
3109       ggc_collect ();
3110 
3111       /* Write out virtual tables as required.  Note that writing out
3112 	 the virtual table for a template class may cause the
3113 	 instantiation of members of that class.  If we write out
3114 	 vtables then we remove the class from our list so we don't
3115 	 have to look at it again.  */
3116 
3117       while (keyed_classes != NULL_TREE
3118 	     && maybe_emit_vtables (TREE_VALUE (keyed_classes)))
3119 	{
3120 	  reconsider = true;
3121 	  keyed_classes = TREE_CHAIN (keyed_classes);
3122 	}
3123 
3124       t = keyed_classes;
3125       if (t != NULL_TREE)
3126 	{
3127 	  tree next = TREE_CHAIN (t);
3128 
3129 	  while (next)
3130 	    {
3131 	      if (maybe_emit_vtables (TREE_VALUE (next)))
3132 		{
3133 		  reconsider = true;
3134 		  TREE_CHAIN (t) = TREE_CHAIN (next);
3135 		}
3136 	      else
3137 		t = next;
3138 
3139 	      next = TREE_CHAIN (t);
3140 	    }
3141 	}
3142 
3143       /* Write out needed type info variables.  We have to be careful
3144 	 looping through unemitted decls, because emit_tinfo_decl may
3145 	 cause other variables to be needed. New elements will be
3146 	 appended, and we remove from the vector those that actually
3147 	 get emitted.  */
3148       for (i = VEC_length (tree, unemitted_tinfo_decls);
3149 	   VEC_iterate (tree, unemitted_tinfo_decls, --i, t);)
3150 	if (emit_tinfo_decl (t))
3151 	  {
3152 	    reconsider = true;
3153 	    VEC_unordered_remove (tree, unemitted_tinfo_decls, i);
3154 	  }
3155 
3156       /* The list of objects with static storage duration is built up
3157 	 in reverse order.  We clear STATIC_AGGREGATES so that any new
3158 	 aggregates added during the initialization of these will be
3159 	 initialized in the correct order when we next come around the
3160 	 loop.  */
3161       vars = prune_vars_needing_no_initialization (&static_aggregates);
3162 
3163       if (vars)
3164 	{
3165 	  /* We need to start a new initialization function each time
3166 	     through the loop.  That's because we need to know which
3167 	     vtables have been referenced, and TREE_SYMBOL_REFERENCED
3168 	     isn't computed until a function is finished, and written
3169 	     out.  That's a deficiency in the back-end.  When this is
3170 	     fixed, these initialization functions could all become
3171 	     inline, with resulting performance improvements.  */
3172 	  tree ssdf_body;
3173 
3174 	  /* Set the line and file, so that it is obviously not from
3175 	     the source file.  */
3176 	  input_location = locus;
3177 	  ssdf_body = start_static_storage_duration_function (ssdf_count);
3178 
3179 	  /* Make sure the back end knows about all the variables.  */
3180 	  write_out_vars (vars);
3181 
3182 	  /* First generate code to do all the initializations.  */
3183 	  if (vars)
3184 	    do_static_initialization_or_destruction (vars, /*initp=*/true);
3185 
3186 	  /* Then, generate code to do all the destructions.  Do these
3187 	     in reverse order so that the most recently constructed
3188 	     variable is the first destroyed.  If we're using
3189 	     __cxa_atexit, then we don't need to do this; functions
3190 	     were registered at initialization time to destroy the
3191 	     local statics.  */
3192 	  if (!flag_use_cxa_atexit && vars)
3193 	    {
3194 	      vars = nreverse (vars);
3195 	      do_static_initialization_or_destruction (vars, /*initp=*/false);
3196 	    }
3197 	  else
3198 	    vars = NULL_TREE;
3199 
3200 	  /* Finish up the static storage duration function for this
3201 	     round.  */
3202 	  input_location = locus;
3203 	  finish_static_storage_duration_function (ssdf_body);
3204 
3205 	  /* All those initializations and finalizations might cause
3206 	     us to need more inline functions, more template
3207 	     instantiations, etc.  */
3208 	  reconsider = true;
3209 	  ssdf_count++;
3210 #ifdef USE_MAPPED_LOCATION
3211 	  /* ??? */
3212 #else
3213 	  locus.line++;
3214 #endif
3215 	}
3216 
3217       /* Go through the set of inline functions whose bodies have not
3218 	 been emitted yet.  If out-of-line copies of these functions
3219 	 are required, emit them.  */
3220       for (i = 0; VEC_iterate (tree, deferred_fns, i, decl); ++i)
3221 	{
3222 	  /* Does it need synthesizing?  */
3223 	  if (DECL_ARTIFICIAL (decl) && ! DECL_INITIAL (decl)
3224 	      && (! DECL_REALLY_EXTERN (decl) || DECL_INLINE (decl)))
3225 	    {
3226 	      /* Even though we're already at the top-level, we push
3227 		 there again.  That way, when we pop back a few lines
3228 		 hence, all of our state is restored.  Otherwise,
3229 		 finish_function doesn't clean things up, and we end
3230 		 up with CURRENT_FUNCTION_DECL set.  */
3231 	      push_to_top_level ();
3232 	      /* The decl's location will mark where it was first
3233 		 needed.  Save that so synthesize method can indicate
3234 		 where it was needed from, in case of error  */
3235 	      input_location = DECL_SOURCE_LOCATION (decl);
3236 	      synthesize_method (decl);
3237 	      pop_from_top_level ();
3238 	      reconsider = true;
3239 	    }
3240 
3241 	  if (!DECL_SAVED_TREE (decl))
3242 	    continue;
3243 
3244 	  /* We lie to the back-end, pretending that some functions
3245 	     are not defined when they really are.  This keeps these
3246 	     functions from being put out unnecessarily.  But, we must
3247 	     stop lying when the functions are referenced, or if they
3248 	     are not comdat since they need to be put out now.  If
3249 	     DECL_INTERFACE_KNOWN, then we have already set
3250 	     DECL_EXTERNAL appropriately, so there's no need to check
3251 	     again, and we do not want to clear DECL_EXTERNAL if a
3252 	     previous call to import_export_decl set it.
3253 
3254 	     This is done in a separate for cycle, because if some
3255 	     deferred function is contained in another deferred
3256 	     function later in deferred_fns varray,
3257 	     rest_of_compilation would skip this function and we
3258 	     really cannot expand the same function twice.  */
3259 	  import_export_decl (decl);
3260 	  if (DECL_NOT_REALLY_EXTERN (decl)
3261 	      && DECL_INITIAL (decl)
3262 	      && decl_needed_p (decl))
3263 	    DECL_EXTERNAL (decl) = 0;
3264 
3265 	  /* If we're going to need to write this function out, and
3266 	     there's already a body for it, create RTL for it now.
3267 	     (There might be no body if this is a method we haven't
3268 	     gotten around to synthesizing yet.)  */
3269 	  if (!DECL_EXTERNAL (decl)
3270 	      && decl_needed_p (decl)
3271 	      && !TREE_ASM_WRITTEN (decl)
3272 	      && !cgraph_node (decl)->local.finalized)
3273 	    {
3274 	      /* We will output the function; no longer consider it in this
3275 		 loop.  */
3276 	      DECL_DEFER_OUTPUT (decl) = 0;
3277 	      /* Generate RTL for this function now that we know we
3278 		 need it.  */
3279 	      expand_or_defer_fn (decl);
3280 	      /* If we're compiling -fsyntax-only pretend that this
3281 		 function has been written out so that we don't try to
3282 		 expand it again.  */
3283 	      if (flag_syntax_only)
3284 		TREE_ASM_WRITTEN (decl) = 1;
3285 	      reconsider = true;
3286 	    }
3287 	}
3288 
3289       if (walk_namespaces (wrapup_globals_for_namespace, /*data=*/0))
3290 	reconsider = true;
3291 
3292       /* Static data members are just like namespace-scope globals.  */
3293       for (i = 0; VEC_iterate (tree, pending_statics, i, decl); ++i)
3294 	{
3295 	  if (var_finalized_p (decl) || DECL_REALLY_EXTERN (decl))
3296 	    continue;
3297 	  import_export_decl (decl);
3298 	  /* If this static data member is needed, provide it to the
3299 	     back end.  */
3300 	  if (DECL_NOT_REALLY_EXTERN (decl) && decl_needed_p (decl))
3301 	    DECL_EXTERNAL (decl) = 0;
3302 	}
3303       if (VEC_length (tree, pending_statics) != 0
3304 	  && wrapup_global_declarations (VEC_address (tree, pending_statics),
3305 					 VEC_length (tree, pending_statics)))
3306 	reconsider = true;
3307 
3308       retries++;
3309     }
3310   while (reconsider);
3311 
3312   /* All used inline functions must have a definition at this point.  */
3313   for (i = 0; VEC_iterate (tree, deferred_fns, i, decl); ++i)
3314     {
3315       if (/* Check online inline functions that were actually used.  */
3316 	  TREE_USED (decl) && DECL_DECLARED_INLINE_P (decl)
3317 	  /* If the definition actually was available here, then the
3318 	     fact that the function was not defined merely represents
3319 	     that for some reason (use of a template repository,
3320 	     #pragma interface, etc.) we decided not to emit the
3321 	     definition here.  */
3322 	  && !DECL_INITIAL (decl)
3323 	  /* An explicit instantiation can be used to specify
3324 	     that the body is in another unit. It will have
3325 	     already verified there was a definition.  */
3326 	  && !DECL_EXPLICIT_INSTANTIATION (decl))
3327 	{
3328 	  warning (0, "inline function %q+D used but never defined", decl);
3329 	  /* Avoid a duplicate warning from check_global_declaration_1.  */
3330 	  TREE_NO_WARNING (decl) = 1;
3331 	}
3332     }
3333 
3334   /* We give C linkage to static constructors and destructors.  */
3335   push_lang_context (lang_name_c);
3336 
3337   /* Generate initialization and destruction functions for all
3338      priorities for which they are required.  */
3339   if (priority_info_map)
3340     splay_tree_foreach (priority_info_map,
3341 			generate_ctor_and_dtor_functions_for_priority,
3342 			/*data=*/&locus);
3343   else
3344     {
3345       /* If we have a ctor or this is obj-c++ and we need a static init,
3346 	 call generate_ctor_or_dtor_function.  */
3347       if (static_ctors || (c_dialect_objc () && objc_static_init_needed_p ()))
3348 	generate_ctor_or_dtor_function (/*constructor_p=*/true,
3349 					DEFAULT_INIT_PRIORITY, &locus);
3350       if (static_dtors)
3351 	generate_ctor_or_dtor_function (/*constructor_p=*/false,
3352 					DEFAULT_INIT_PRIORITY, &locus);
3353     }
3354 
3355   /* We're done with the splay-tree now.  */
3356   if (priority_info_map)
3357     splay_tree_delete (priority_info_map);
3358 
3359   /* Generate any missing aliases.  */
3360   maybe_apply_pending_pragma_weaks ();
3361 
3362   /* We're done with static constructors, so we can go back to "C++"
3363      linkage now.  */
3364   pop_lang_context ();
3365 
3366   cgraph_finalize_compilation_unit ();
3367   cgraph_optimize ();
3368 
3369   /* Now, issue warnings about static, but not defined, functions,
3370      etc., and emit debugging information.  */
3371   walk_namespaces (wrapup_globals_for_namespace, /*data=*/&reconsider);
3372   if (VEC_length (tree, pending_statics) != 0)
3373     {
3374       check_global_declarations (VEC_address (tree, pending_statics),
3375 				 VEC_length (tree, pending_statics));
3376       emit_debug_global_declarations (VEC_address (tree, pending_statics),
3377 				      VEC_length (tree, pending_statics));
3378     }
3379 
3380   /* Generate hidden aliases for Java.  */
3381   build_java_method_aliases ();
3382 
3383   finish_repo ();
3384 
3385   /* The entire file is now complete.  If requested, dump everything
3386      to a file.  */
3387   {
3388     int flags;
3389     FILE *stream = dump_begin (TDI_tu, &flags);
3390 
3391     if (stream)
3392       {
3393 	dump_node (global_namespace, flags & ~TDF_SLIM, stream);
3394 	dump_end (TDI_tu, stream);
3395       }
3396   }
3397 
3398   timevar_pop (TV_VARCONST);
3399 
3400   if (flag_detailed_statistics)
3401     {
3402       dump_tree_statistics ();
3403       dump_time_statistics ();
3404     }
3405   input_location = locus;
3406 
3407 #ifdef ENABLE_CHECKING
3408   validate_conversion_obstack ();
3409 #endif /* ENABLE_CHECKING */
3410 }
3411 
3412 /* FN is an OFFSET_REF, DOTSTAR_EXPR or MEMBER_REF indicating the
3413    function to call in parse-tree form; it has not yet been
3414    semantically analyzed.  ARGS are the arguments to the function.
3415    They have already been semantically analyzed.  */
3416 
3417 tree
build_offset_ref_call_from_tree(tree fn,tree args)3418 build_offset_ref_call_from_tree (tree fn, tree args)
3419 {
3420   tree orig_fn;
3421   tree orig_args;
3422   tree expr;
3423   tree object;
3424 
3425   orig_fn = fn;
3426   orig_args = args;
3427   object = TREE_OPERAND (fn, 0);
3428 
3429   if (processing_template_decl)
3430     {
3431       gcc_assert (TREE_CODE (fn) == DOTSTAR_EXPR
3432 		  || TREE_CODE (fn) == MEMBER_REF);
3433       if (type_dependent_expression_p (fn)
3434 	  || any_type_dependent_arguments_p (args))
3435 	return build_min_nt (CALL_EXPR, fn, args, NULL_TREE);
3436 
3437       /* Transform the arguments and add the implicit "this"
3438 	 parameter.  That must be done before the FN is transformed
3439 	 because we depend on the form of FN.  */
3440       args = build_non_dependent_args (args);
3441       if (TREE_CODE (fn) == DOTSTAR_EXPR)
3442 	object = build_unary_op (ADDR_EXPR, object, 0);
3443       object = build_non_dependent_expr (object);
3444       args = tree_cons (NULL_TREE, object, args);
3445       /* Now that the arguments are done, transform FN.  */
3446       fn = build_non_dependent_expr (fn);
3447     }
3448 
3449   /* A qualified name corresponding to a bound pointer-to-member is
3450      represented as an OFFSET_REF:
3451 
3452 	struct B { void g(); };
3453 	void (B::*p)();
3454 	void B::g() { (this->*p)(); }  */
3455   if (TREE_CODE (fn) == OFFSET_REF)
3456     {
3457       tree object_addr = build_unary_op (ADDR_EXPR, object, 0);
3458       fn = TREE_OPERAND (fn, 1);
3459       fn = get_member_function_from_ptrfunc (&object_addr, fn);
3460       args = tree_cons (NULL_TREE, object_addr, args);
3461     }
3462 
3463   expr = build_function_call (fn, args);
3464   if (processing_template_decl && expr != error_mark_node)
3465     return build_min_non_dep (CALL_EXPR, expr, orig_fn, orig_args, NULL_TREE);
3466   return expr;
3467 }
3468 
3469 
3470 void
check_default_args(tree x)3471 check_default_args (tree x)
3472 {
3473   tree arg = TYPE_ARG_TYPES (TREE_TYPE (x));
3474   bool saw_def = false;
3475   int i = 0 - (TREE_CODE (TREE_TYPE (x)) == METHOD_TYPE);
3476   for (; arg && arg != void_list_node; arg = TREE_CHAIN (arg), ++i)
3477     {
3478       if (TREE_PURPOSE (arg))
3479 	saw_def = true;
3480       else if (saw_def)
3481 	{
3482 	  error ("default argument missing for parameter %P of %q+#D", i, x);
3483 	  TREE_PURPOSE (arg) = error_mark_node;
3484 	}
3485     }
3486 }
3487 
3488 /* Mark DECL (either a _DECL or a BASELINK) as "used" in the program.
3489    If DECL is a specialization or implicitly declared class member,
3490    generate the actual definition.  */
3491 
3492 void
mark_used(tree decl)3493 mark_used (tree decl)
3494 {
3495   HOST_WIDE_INT saved_processing_template_decl = 0;
3496 
3497   /* If DECL is a BASELINK for a single function, then treat it just
3498      like the DECL for the function.  Otherwise, if the BASELINK is
3499      for an overloaded function, we don't know which function was
3500      actually used until after overload resolution.  */
3501   if (TREE_CODE (decl) == BASELINK)
3502     {
3503       decl = BASELINK_FUNCTIONS (decl);
3504       if (really_overloaded_fn (decl))
3505 	return;
3506       decl = OVL_CURRENT (decl);
3507     }
3508 
3509   TREE_USED (decl) = 1;
3510   if (DECL_CLONED_FUNCTION_P (decl))
3511     TREE_USED (DECL_CLONED_FUNCTION (decl)) = 1;
3512   /* If we don't need a value, then we don't need to synthesize DECL.  */
3513   if (skip_evaluation)
3514     return;
3515   /* Normally, we can wait until instantiation-time to synthesize
3516      DECL.  However, if DECL is a static data member initialized with
3517      a constant, we need the value right now because a reference to
3518      such a data member is not value-dependent.  */
3519   if (TREE_CODE (decl) == VAR_DECL
3520       && DECL_INITIALIZED_BY_CONSTANT_EXPRESSION_P (decl)
3521       && DECL_CLASS_SCOPE_P (decl))
3522     {
3523       /* Don't try to instantiate members of dependent types.  We
3524 	 cannot just use dependent_type_p here because this function
3525 	 may be called from fold_non_dependent_expr, and then we may
3526 	 see dependent types, even though processing_template_decl
3527 	 will not be set.  */
3528       if (CLASSTYPE_TEMPLATE_INFO ((DECL_CONTEXT (decl)))
3529 	  && uses_template_parms (CLASSTYPE_TI_ARGS (DECL_CONTEXT (decl))))
3530 	return;
3531       /* Pretend that we are not in a template, even if we are, so
3532 	 that the static data member initializer will be processed.  */
3533       saved_processing_template_decl = processing_template_decl;
3534       processing_template_decl = 0;
3535     }
3536 
3537   if (processing_template_decl)
3538     return;
3539 
3540   if (TREE_CODE (decl) == FUNCTION_DECL && DECL_DECLARED_INLINE_P (decl)
3541       && !TREE_ASM_WRITTEN (decl))
3542     /* Remember it, so we can check it was defined.  */
3543     {
3544       if (DECL_DEFERRED_FN (decl))
3545 	return;
3546 
3547       /* Remember the current location for a function we will end up
3548 	 synthesizing.  Then we can inform the user where it was
3549 	 required in the case of error.  */
3550       if (DECL_ARTIFICIAL (decl) && DECL_NONSTATIC_MEMBER_FUNCTION_P (decl)
3551 	  && !DECL_THUNK_P (decl))
3552 	DECL_SOURCE_LOCATION (decl) = input_location;
3553 
3554       note_vague_linkage_fn (decl);
3555     }
3556 
3557   assemble_external (decl);
3558 
3559   /* Is it a synthesized method that needs to be synthesized?  */
3560   if (TREE_CODE (decl) == FUNCTION_DECL
3561       && DECL_NONSTATIC_MEMBER_FUNCTION_P (decl)
3562       && DECL_ARTIFICIAL (decl)
3563       && !DECL_THUNK_P (decl)
3564       && ! DECL_INITIAL (decl)
3565       /* Kludge: don't synthesize for default args.  Unfortunately this
3566 	 rules out initializers of namespace-scoped objects too, but
3567 	 it's sort-of ok if the implicit ctor or dtor decl keeps
3568 	 pointing to the class location.  */
3569       && current_function_decl)
3570     {
3571       synthesize_method (decl);
3572       /* If we've already synthesized the method we don't need to
3573 	 do the instantiation test below.  */
3574     }
3575   else if ((DECL_NON_THUNK_FUNCTION_P (decl) || TREE_CODE (decl) == VAR_DECL)
3576 	   && DECL_LANG_SPECIFIC (decl) && DECL_TEMPLATE_INFO (decl)
3577 	   && (!DECL_EXPLICIT_INSTANTIATION (decl)
3578 	       || (TREE_CODE (decl) == FUNCTION_DECL
3579 		   && DECL_INLINE (DECL_TEMPLATE_RESULT
3580 				   (template_for_substitution (decl))))
3581 	       /* We need to instantiate static data members so that there
3582 		  initializers are available in integral constant
3583 		  expressions.  */
3584 	       || (TREE_CODE (decl) == VAR_DECL
3585 		   && DECL_INITIALIZED_BY_CONSTANT_EXPRESSION_P (decl))))
3586     /* If this is a function or variable that is an instance of some
3587        template, we now know that we will need to actually do the
3588        instantiation. We check that DECL is not an explicit
3589        instantiation because that is not checked in instantiate_decl.
3590 
3591        We put off instantiating functions in order to improve compile
3592        times.  Maintaining a stack of active functions is expensive,
3593        and the inliner knows to instantiate any functions it might
3594        need.  Therefore, we always try to defer instantiation.  */
3595     instantiate_decl (decl, /*defer_ok=*/true,
3596 		      /*expl_inst_class_mem_p=*/false);
3597 
3598   processing_template_decl = saved_processing_template_decl;
3599 }
3600 
3601 #include "gt-cp-decl2.h"
3602