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