c-semantics.c (make_rtl_for_local_static): Use TREE_ASM_WRITTEN to figure out whether...
[gcc.git] / gcc / cp / pt.c
1 /* Handle parameterized types (templates) for GNU C++.
2 Copyright (C) 1992, 1993, 1994, 1995, 1996, 1997, 1998, 1999, 2000
3 Free Software Foundation, Inc.
4 Written by Ken Raeburn (raeburn@cygnus.com) while at Watchmaker Computing.
5 Rewritten by Jason Merrill (jason@cygnus.com).
6
7 This file is part of GNU CC.
8
9 GNU CC is free software; you can redistribute it and/or modify
10 it under the terms of the GNU General Public License as published by
11 the Free Software Foundation; either version 2, or (at your option)
12 any later version.
13
14 GNU CC is distributed in the hope that it will be useful,
15 but WITHOUT ANY WARRANTY; without even the implied warranty of
16 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
17 GNU General Public License for more details.
18
19 You should have received a copy of the GNU General Public License
20 along with GNU CC; see the file COPYING. If not, write to
21 the Free Software Foundation, 59 Temple Place - Suite 330,
22 Boston, MA 02111-1307, USA. */
23
24 /* Known bugs or deficiencies include:
25
26 all methods must be provided in header files; can't use a source
27 file that contains only the method templates and "just win". */
28
29 #include "config.h"
30 #include "system.h"
31 #include "obstack.h"
32
33 #include "tree.h"
34 #include "flags.h"
35 #include "cp-tree.h"
36 #include "decl.h"
37 #include "parse.h"
38 #include "lex.h"
39 #include "output.h"
40 #include "defaults.h"
41 #include "except.h"
42 #include "toplev.h"
43 #include "rtl.h"
44 #include "defaults.h"
45 #include "ggc.h"
46 #include "hashtab.h"
47 #include "timevar.h"
48
49 /* The type of functions taking a tree, and some additional data, and
50 returning an int. */
51 typedef int (*tree_fn_t) PARAMS ((tree, void*));
52
53 extern struct obstack permanent_obstack;
54
55 /* The PENDING_TEMPLATES is a TREE_LIST of templates whose
56 instantiations have been deferred, either because their definitions
57 were not yet available, or because we were putting off doing the
58 work. The TREE_PURPOSE of each entry is a SRCLOC indicating where
59 the instantiate request occurred; the TREE_VALUE is a either a DECL
60 (for a function or static data member), or a TYPE (for a class)
61 indicating what we are hoping to instantiate. */
62 static tree pending_templates;
63 static tree *template_tail = &pending_templates;
64
65 static tree maybe_templates;
66 static tree *maybe_template_tail = &maybe_templates;
67
68 int processing_template_parmlist;
69 static int template_header_count;
70
71 static tree saved_trees;
72 static varray_type inline_parm_levels;
73 static size_t inline_parm_levels_used;
74
75 tree current_tinst_level;
76
77 /* A map from local variable declarations in the body of the template
78 presently being instantiated to the corresponding instantiated
79 local variables. */
80 static htab_t local_specializations;
81
82 #define obstack_chunk_alloc xmalloc
83 #define obstack_chunk_free free
84
85 #define UNIFY_ALLOW_NONE 0
86 #define UNIFY_ALLOW_MORE_CV_QUAL 1
87 #define UNIFY_ALLOW_LESS_CV_QUAL 2
88 #define UNIFY_ALLOW_DERIVED 4
89 #define UNIFY_ALLOW_INTEGER 8
90
91 #define GTB_VIA_VIRTUAL 1 /* The base class we are examining is
92 virtual, or a base class of a virtual
93 base. */
94 #define GTB_IGNORE_TYPE 2 /* We don't need to try to unify the current
95 type with the desired type. */
96
97 static int resolve_overloaded_unification PARAMS ((tree, tree, tree, tree,
98 unification_kind_t, int));
99 static int try_one_overload PARAMS ((tree, tree, tree, tree, tree,
100 unification_kind_t, int));
101 static int unify PARAMS ((tree, tree, tree, tree, int));
102 static void add_pending_template PARAMS ((tree));
103 static int push_tinst_level PARAMS ((tree));
104 static void reopen_tinst_level PARAMS ((tree));
105 static tree classtype_mangled_name PARAMS ((tree));
106 static char *mangle_class_name_for_template PARAMS ((char *, tree, tree));
107 static tree tsubst_initializer_list PARAMS ((tree, tree));
108 static int list_eq PARAMS ((tree, tree));
109 static tree get_class_bindings PARAMS ((tree, tree, tree));
110 static tree coerce_template_parms PARAMS ((tree, tree, tree, int, int));
111 static void tsubst_enum PARAMS ((tree, tree, tree));
112 static tree add_to_template_args PARAMS ((tree, tree));
113 static tree add_outermost_template_args PARAMS ((tree, tree));
114 static void maybe_adjust_types_for_deduction PARAMS ((unification_kind_t, tree*,
115 tree*));
116 static int type_unification_real PARAMS ((tree, tree, tree, tree,
117 int, unification_kind_t, int));
118 static void note_template_header PARAMS ((int));
119 static tree maybe_fold_nontype_arg PARAMS ((tree));
120 static tree convert_nontype_argument PARAMS ((tree, tree));
121 static tree convert_template_argument PARAMS ((tree, tree, tree, int,
122 int , tree));
123 static tree get_bindings_overload PARAMS ((tree, tree, tree));
124 static int for_each_template_parm PARAMS ((tree, tree_fn_t, void*));
125 static tree build_template_parm_index PARAMS ((int, int, int, tree, tree));
126 static int inline_needs_template_parms PARAMS ((tree));
127 static void push_inline_template_parms_recursive PARAMS ((tree, int));
128 static tree retrieve_specialization PARAMS ((tree, tree));
129 static tree retrieve_local_specialization PARAMS ((tree));
130 static tree register_specialization PARAMS ((tree, tree, tree));
131 static tree register_local_specialization PARAMS ((tree, tree));
132 static int unregister_specialization PARAMS ((tree, tree));
133 static tree reduce_template_parm_level PARAMS ((tree, tree, int));
134 static tree build_template_decl PARAMS ((tree, tree));
135 static int mark_template_parm PARAMS ((tree, void *));
136 static tree tsubst_friend_function PARAMS ((tree, tree));
137 static tree tsubst_friend_class PARAMS ((tree, tree));
138 static tree get_bindings_real PARAMS ((tree, tree, tree, int));
139 static int template_decl_level PARAMS ((tree));
140 static tree maybe_get_template_decl_from_type_decl PARAMS ((tree));
141 static int check_cv_quals_for_unify PARAMS ((int, tree, tree));
142 static tree tsubst_template_arg_vector PARAMS ((tree, tree, int));
143 static tree tsubst_template_parms PARAMS ((tree, tree, int));
144 static void regenerate_decl_from_template PARAMS ((tree, tree));
145 static tree most_specialized PARAMS ((tree, tree, tree));
146 static tree most_specialized_class PARAMS ((tree, tree));
147 static void set_mangled_name_for_template_decl PARAMS ((tree));
148 static int template_class_depth_real PARAMS ((tree, int));
149 static tree tsubst_aggr_type PARAMS ((tree, tree, int, tree, int));
150 static tree tsubst_decl PARAMS ((tree, tree, tree, tree));
151 static tree tsubst_arg_types PARAMS ((tree, tree, int, tree));
152 static tree tsubst_function_type PARAMS ((tree, tree, int, tree));
153 static void check_specialization_scope PARAMS ((void));
154 static tree process_partial_specialization PARAMS ((tree));
155 static void set_current_access_from_decl PARAMS ((tree));
156 static void check_default_tmpl_args PARAMS ((tree, tree, int, int));
157 static tree tsubst_call_declarator_parms PARAMS ((tree, tree, int, tree));
158 static tree get_template_base_recursive PARAMS ((tree, tree,
159 tree, tree, tree, int));
160 static tree get_template_base PARAMS ((tree, tree, tree, tree));
161 static tree try_class_unification PARAMS ((tree, tree, tree, tree));
162 static int coerce_template_template_parms PARAMS ((tree, tree, int,
163 tree, tree));
164 static tree determine_specialization PARAMS ((tree, tree, tree *, int));
165 static int template_args_equal PARAMS ((tree, tree));
166 static void print_template_context PARAMS ((int));
167 static void tsubst_default_arguments PARAMS ((tree));
168 static tree for_each_template_parm_r PARAMS ((tree *, int *, void *));
169 static tree instantiate_clone PARAMS ((tree, tree));
170
171 /* Called once to initialize pt.c. */
172
173 void
174 init_pt ()
175 {
176 ggc_add_tree_root (&pending_templates, 1);
177 ggc_add_tree_root (&maybe_templates, 1);
178 ggc_add_tree_root (&saved_trees, 1);
179 ggc_add_tree_root (&current_tinst_level, 1);
180 }
181
182 /* Do any processing required when DECL (a member template declaration
183 using TEMPLATE_PARAMETERS as its innermost parameter list) is
184 finished. Returns the TEMPLATE_DECL corresponding to DECL, unless
185 it is a specialization, in which case the DECL itself is returned. */
186
187 tree
188 finish_member_template_decl (decl)
189 tree decl;
190 {
191 if (decl == NULL_TREE || decl == void_type_node)
192 return NULL_TREE;
193 else if (decl == error_mark_node)
194 /* By returning NULL_TREE, the parser will just ignore this
195 declaration. We have already issued the error. */
196 return NULL_TREE;
197 else if (TREE_CODE (decl) == TREE_LIST)
198 {
199 /* Assume that the class is the only declspec. */
200 decl = TREE_VALUE (decl);
201 if (IS_AGGR_TYPE (decl) && CLASSTYPE_TEMPLATE_INFO (decl)
202 && ! CLASSTYPE_TEMPLATE_SPECIALIZATION (decl))
203 {
204 tree tmpl = CLASSTYPE_TI_TEMPLATE (decl);
205 check_member_template (tmpl);
206 return tmpl;
207 }
208 return NULL_TREE;
209 }
210 else if (TREE_CODE (decl) == FIELD_DECL)
211 cp_error ("data member `%D' cannot be a member template", decl);
212 else if (DECL_TEMPLATE_INFO (decl))
213 {
214 if (!DECL_TEMPLATE_SPECIALIZATION (decl))
215 {
216 check_member_template (DECL_TI_TEMPLATE (decl));
217 return DECL_TI_TEMPLATE (decl);
218 }
219 else
220 return decl;
221 }
222 else
223 cp_error ("invalid member template declaration `%D'", decl);
224
225 return error_mark_node;
226 }
227
228 /* Returns the template nesting level of the indicated class TYPE.
229
230 For example, in:
231 template <class T>
232 struct A
233 {
234 template <class U>
235 struct B {};
236 };
237
238 A<T>::B<U> has depth two, while A<T> has depth one.
239 Both A<T>::B<int> and A<int>::B<U> have depth one, if
240 COUNT_SPECIALIZATIONS is 0 or if they are instantiations, not
241 specializations.
242
243 This function is guaranteed to return 0 if passed NULL_TREE so
244 that, for example, `template_class_depth (current_class_type)' is
245 always safe. */
246
247 static int
248 template_class_depth_real (type, count_specializations)
249 tree type;
250 int count_specializations;
251 {
252 int depth;
253
254 for (depth = 0;
255 type && TREE_CODE (type) != NAMESPACE_DECL;
256 type = (TREE_CODE (type) == FUNCTION_DECL)
257 ? CP_DECL_CONTEXT (type) : TYPE_CONTEXT (type))
258 {
259 if (TREE_CODE (type) != FUNCTION_DECL)
260 {
261 if (CLASSTYPE_TEMPLATE_INFO (type)
262 && PRIMARY_TEMPLATE_P (CLASSTYPE_TI_TEMPLATE (type))
263 && ((count_specializations
264 && CLASSTYPE_TEMPLATE_SPECIALIZATION (type))
265 || uses_template_parms (CLASSTYPE_TI_ARGS (type))))
266 ++depth;
267 }
268 else
269 {
270 if (DECL_TEMPLATE_INFO (type)
271 && PRIMARY_TEMPLATE_P (DECL_TI_TEMPLATE (type))
272 && ((count_specializations
273 && DECL_TEMPLATE_SPECIALIZATION (type))
274 || uses_template_parms (DECL_TI_ARGS (type))))
275 ++depth;
276 }
277 }
278
279 return depth;
280 }
281
282 /* Returns the template nesting level of the indicated class TYPE.
283 Like template_class_depth_real, but instantiations do not count in
284 the depth. */
285
286 int
287 template_class_depth (type)
288 tree type;
289 {
290 return template_class_depth_real (type, /*count_specializations=*/0);
291 }
292
293 /* Returns 1 if processing DECL as part of do_pending_inlines
294 needs us to push template parms. */
295
296 static int
297 inline_needs_template_parms (decl)
298 tree decl;
299 {
300 if (! DECL_TEMPLATE_INFO (decl))
301 return 0;
302
303 return (TMPL_PARMS_DEPTH (DECL_TEMPLATE_PARMS (most_general_template (decl)))
304 > (processing_template_decl + DECL_TEMPLATE_SPECIALIZATION (decl)));
305 }
306
307 /* Subroutine of maybe_begin_member_template_processing.
308 Push the template parms in PARMS, starting from LEVELS steps into the
309 chain, and ending at the beginning, since template parms are listed
310 innermost first. */
311
312 static void
313 push_inline_template_parms_recursive (parmlist, levels)
314 tree parmlist;
315 int levels;
316 {
317 tree parms = TREE_VALUE (parmlist);
318 int i;
319
320 if (levels > 1)
321 push_inline_template_parms_recursive (TREE_CHAIN (parmlist), levels - 1);
322
323 ++processing_template_decl;
324 current_template_parms
325 = tree_cons (build_int_2 (0, processing_template_decl),
326 parms, current_template_parms);
327 TEMPLATE_PARMS_FOR_INLINE (current_template_parms) = 1;
328
329 pushlevel (0);
330 for (i = 0; i < TREE_VEC_LENGTH (parms); ++i)
331 {
332 tree parm = TREE_VALUE (TREE_VEC_ELT (parms, i));
333 my_friendly_assert (DECL_P (parm), 0);
334
335 switch (TREE_CODE (parm))
336 {
337 case TYPE_DECL:
338 case TEMPLATE_DECL:
339 pushdecl (parm);
340 break;
341
342 case PARM_DECL:
343 {
344 /* Make a CONST_DECL as is done in process_template_parm.
345 It is ugly that we recreate this here; the original
346 version built in process_template_parm is no longer
347 available. */
348 tree decl = build_decl (CONST_DECL, DECL_NAME (parm),
349 TREE_TYPE (parm));
350 DECL_ARTIFICIAL (decl) = 1;
351 DECL_INITIAL (decl) = DECL_INITIAL (parm);
352 SET_DECL_TEMPLATE_PARM_P (decl);
353 pushdecl (decl);
354 }
355 break;
356
357 default:
358 my_friendly_abort (0);
359 }
360 }
361 }
362
363 /* Restore the template parameter context for a member template or
364 a friend template defined in a class definition. */
365
366 void
367 maybe_begin_member_template_processing (decl)
368 tree decl;
369 {
370 tree parms;
371 int levels = 0;
372
373 if (inline_needs_template_parms (decl))
374 {
375 parms = DECL_TEMPLATE_PARMS (most_general_template (decl));
376 levels = TMPL_PARMS_DEPTH (parms) - processing_template_decl;
377
378 if (DECL_TEMPLATE_SPECIALIZATION (decl))
379 {
380 --levels;
381 parms = TREE_CHAIN (parms);
382 }
383
384 push_inline_template_parms_recursive (parms, levels);
385 }
386
387 /* Remember how many levels of template parameters we pushed so that
388 we can pop them later. */
389 if (!inline_parm_levels)
390 VARRAY_INT_INIT (inline_parm_levels, 4, "inline_parm_levels");
391 if (inline_parm_levels_used == inline_parm_levels->num_elements)
392 VARRAY_GROW (inline_parm_levels, 2 * inline_parm_levels_used);
393 VARRAY_INT (inline_parm_levels, inline_parm_levels_used) = levels;
394 ++inline_parm_levels_used;
395 }
396
397 /* Undo the effects of begin_member_template_processing. */
398
399 void
400 maybe_end_member_template_processing ()
401 {
402 int i;
403
404 if (!inline_parm_levels_used)
405 return;
406
407 --inline_parm_levels_used;
408 for (i = 0;
409 i < VARRAY_INT (inline_parm_levels, inline_parm_levels_used);
410 ++i)
411 {
412 --processing_template_decl;
413 current_template_parms = TREE_CHAIN (current_template_parms);
414 poplevel (0, 0, 0);
415 }
416 }
417
418 /* Returns non-zero iff T is a member template function. We must be
419 careful as in
420
421 template <class T> class C { void f(); }
422
423 Here, f is a template function, and a member, but not a member
424 template. This function does not concern itself with the origin of
425 T, only its present state. So if we have
426
427 template <class T> class C { template <class U> void f(U); }
428
429 then neither C<int>::f<char> nor C<T>::f<double> is considered
430 to be a member template. But, `template <class U> void
431 C<int>::f(U)' is considered a member template. */
432
433 int
434 is_member_template (t)
435 tree t;
436 {
437 if (!DECL_FUNCTION_TEMPLATE_P (t))
438 /* Anything that isn't a function or a template function is
439 certainly not a member template. */
440 return 0;
441
442 /* A local class can't have member templates. */
443 if (decl_function_context (t))
444 return 0;
445
446 return (DECL_FUNCTION_MEMBER_P (DECL_TEMPLATE_RESULT (t))
447 /* If there are more levels of template parameters than
448 there are template classes surrounding the declaration,
449 then we have a member template. */
450 && (TMPL_PARMS_DEPTH (DECL_TEMPLATE_PARMS (t)) >
451 template_class_depth (DECL_CONTEXT (t))));
452 }
453
454 #if 0 /* UNUSED */
455 /* Returns non-zero iff T is a member template class. See
456 is_member_template for a description of what precisely constitutes
457 a member template. */
458
459 int
460 is_member_template_class (t)
461 tree t;
462 {
463 if (!DECL_CLASS_TEMPLATE_P (t))
464 /* Anything that isn't a class template, is certainly not a member
465 template. */
466 return 0;
467
468 if (!DECL_CLASS_SCOPE_P (t))
469 /* Anything whose context isn't a class type is surely not a
470 member template. */
471 return 0;
472
473 /* If there are more levels of template parameters than there are
474 template classes surrounding the declaration, then we have a
475 member template. */
476 return (TMPL_PARMS_DEPTH (DECL_TEMPLATE_PARMS (t)) >
477 template_class_depth (DECL_CONTEXT (t)));
478 }
479 #endif
480
481 /* Return a new template argument vector which contains all of ARGS,
482 but has as its innermost set of arguments the EXTRA_ARGS. */
483
484 static tree
485 add_to_template_args (args, extra_args)
486 tree args;
487 tree extra_args;
488 {
489 tree new_args;
490 int extra_depth;
491 int i;
492 int j;
493
494 extra_depth = TMPL_ARGS_DEPTH (extra_args);
495 new_args = make_tree_vec (TMPL_ARGS_DEPTH (args) + extra_depth);
496
497 for (i = 1; i <= TMPL_ARGS_DEPTH (args); ++i)
498 SET_TMPL_ARGS_LEVEL (new_args, i, TMPL_ARGS_LEVEL (args, i));
499
500 for (j = 1; j <= extra_depth; ++j, ++i)
501 SET_TMPL_ARGS_LEVEL (new_args, i, TMPL_ARGS_LEVEL (extra_args, j));
502
503 return new_args;
504 }
505
506 /* Like add_to_template_args, but only the outermost ARGS are added to
507 the EXTRA_ARGS. In particular, all but TMPL_ARGS_DEPTH
508 (EXTRA_ARGS) levels are added. This function is used to combine
509 the template arguments from a partial instantiation with the
510 template arguments used to attain the full instantiation from the
511 partial instantiation. */
512
513 static tree
514 add_outermost_template_args (args, extra_args)
515 tree args;
516 tree extra_args;
517 {
518 tree new_args;
519
520 /* If there are more levels of EXTRA_ARGS than there are ARGS,
521 something very fishy is going on. */
522 my_friendly_assert (TMPL_ARGS_DEPTH (args) >= TMPL_ARGS_DEPTH (extra_args),
523 0);
524
525 /* If *all* the new arguments will be the EXTRA_ARGS, just return
526 them. */
527 if (TMPL_ARGS_DEPTH (args) == TMPL_ARGS_DEPTH (extra_args))
528 return extra_args;
529
530 /* For the moment, we make ARGS look like it contains fewer levels. */
531 TREE_VEC_LENGTH (args) -= TMPL_ARGS_DEPTH (extra_args);
532
533 new_args = add_to_template_args (args, extra_args);
534
535 /* Now, we restore ARGS to its full dimensions. */
536 TREE_VEC_LENGTH (args) += TMPL_ARGS_DEPTH (extra_args);
537
538 return new_args;
539 }
540
541 /* Return the N levels of innermost template arguments from the ARGS. */
542
543 tree
544 get_innermost_template_args (args, n)
545 tree args;
546 int n;
547 {
548 tree new_args;
549 int extra_levels;
550 int i;
551
552 my_friendly_assert (n >= 0, 20000603);
553
554 /* If N is 1, just return the innermost set of template arguments. */
555 if (n == 1)
556 return TMPL_ARGS_LEVEL (args, TMPL_ARGS_DEPTH (args));
557
558 /* If we're not removing anything, just return the arguments we were
559 given. */
560 extra_levels = TMPL_ARGS_DEPTH (args) - n;
561 my_friendly_assert (extra_levels >= 0, 20000603);
562 if (extra_levels == 0)
563 return args;
564
565 /* Make a new set of arguments, not containing the outer arguments. */
566 new_args = make_tree_vec (n);
567 for (i = 1; i <= n; ++i)
568 SET_TMPL_ARGS_LEVEL (new_args, i,
569 TMPL_ARGS_LEVEL (args, i + extra_levels));
570
571 return new_args;
572 }
573
574 /* We've got a template header coming up; push to a new level for storing
575 the parms. */
576
577 void
578 begin_template_parm_list ()
579 {
580 /* We use a non-tag-transparent scope here, which causes pushtag to
581 put tags in this scope, rather than in the enclosing class or
582 namespace scope. This is the right thing, since we want
583 TEMPLATE_DECLS, and not TYPE_DECLS for template classes. For a
584 global template class, push_template_decl handles putting the
585 TEMPLATE_DECL into top-level scope. For a nested template class,
586 e.g.:
587
588 template <class T> struct S1 {
589 template <class T> struct S2 {};
590 };
591
592 pushtag contains special code to call pushdecl_with_scope on the
593 TEMPLATE_DECL for S2. */
594 begin_scope (sk_template_parms);
595 ++processing_template_decl;
596 ++processing_template_parmlist;
597 note_template_header (0);
598 }
599
600 /* This routine is called when a specialization is declared. If it is
601 illegal to declare a specialization here, an error is reported. */
602
603 static void
604 check_specialization_scope ()
605 {
606 tree scope = current_scope ();
607
608 /* [temp.expl.spec]
609
610 An explicit specialization shall be declared in the namespace of
611 which the template is a member, or, for member templates, in the
612 namespace of which the enclosing class or enclosing class
613 template is a member. An explicit specialization of a member
614 function, member class or static data member of a class template
615 shall be declared in the namespace of which the class template
616 is a member. */
617 if (scope && TREE_CODE (scope) != NAMESPACE_DECL)
618 cp_error ("explicit specialization in non-namespace scope `%D'",
619 scope);
620
621 /* [temp.expl.spec]
622
623 In an explicit specialization declaration for a member of a class
624 template or a member template that appears in namespace scope,
625 the member template and some of its enclosing class templates may
626 remain unspecialized, except that the declaration shall not
627 explicitly specialize a class member template if its enclosing
628 class templates are not explicitly specialized as well. */
629 if (current_template_parms)
630 cp_error ("enclosing class templates are not explicitly specialized");
631 }
632
633 /* We've just seen template <>. */
634
635 void
636 begin_specialization ()
637 {
638 begin_scope (sk_template_spec);
639 note_template_header (1);
640 check_specialization_scope ();
641 }
642
643 /* Called at then end of processing a declaration preceeded by
644 template<>. */
645
646 void
647 end_specialization ()
648 {
649 finish_scope ();
650 reset_specialization ();
651 }
652
653 /* Any template <>'s that we have seen thus far are not referring to a
654 function specialization. */
655
656 void
657 reset_specialization ()
658 {
659 processing_specialization = 0;
660 template_header_count = 0;
661 }
662
663 /* We've just seen a template header. If SPECIALIZATION is non-zero,
664 it was of the form template <>. */
665
666 static void
667 note_template_header (specialization)
668 int specialization;
669 {
670 processing_specialization = specialization;
671 template_header_count++;
672 }
673
674 /* We're beginning an explicit instantiation. */
675
676 void
677 begin_explicit_instantiation ()
678 {
679 ++processing_explicit_instantiation;
680 }
681
682
683 void
684 end_explicit_instantiation ()
685 {
686 my_friendly_assert(processing_explicit_instantiation > 0, 0);
687 --processing_explicit_instantiation;
688 }
689
690 /* The TYPE is being declared. If it is a template type, that means it
691 is a partial specialization. Do appropriate error-checking. */
692
693 void
694 maybe_process_partial_specialization (type)
695 tree type;
696 {
697 if (IS_AGGR_TYPE (type) && CLASSTYPE_USE_TEMPLATE (type))
698 {
699 if (CLASSTYPE_IMPLICIT_INSTANTIATION (type)
700 && !COMPLETE_TYPE_P (type))
701 {
702 if (current_namespace
703 != decl_namespace_context (CLASSTYPE_TI_TEMPLATE (type)))
704 {
705 cp_pedwarn ("specializing `%#T' in different namespace", type);
706 cp_pedwarn_at (" from definition of `%#D'",
707 CLASSTYPE_TI_TEMPLATE (type));
708 }
709 SET_CLASSTYPE_TEMPLATE_SPECIALIZATION (type);
710 if (processing_template_decl)
711 push_template_decl (TYPE_MAIN_DECL (type));
712 }
713 else if (CLASSTYPE_TEMPLATE_INSTANTIATION (type))
714 cp_error ("specialization of `%T' after instantiation", type);
715 }
716 else if (processing_specialization)
717 cp_error ("explicit specialization of non-template `%T'", type);
718 }
719
720 /* Retrieve the specialization (in the sense of [temp.spec] - a
721 specialization is either an instantiation or an explicit
722 specialization) of TMPL for the given template ARGS. If there is
723 no such specialization, return NULL_TREE. The ARGS are a vector of
724 arguments, or a vector of vectors of arguments, in the case of
725 templates with more than one level of parameters. */
726
727 static tree
728 retrieve_specialization (tmpl, args)
729 tree tmpl;
730 tree args;
731 {
732 tree s;
733
734 my_friendly_assert (TREE_CODE (tmpl) == TEMPLATE_DECL, 0);
735
736 /* There should be as many levels of arguments as there are
737 levels of parameters. */
738 my_friendly_assert (TMPL_ARGS_DEPTH (args)
739 == TMPL_PARMS_DEPTH (DECL_TEMPLATE_PARMS (tmpl)),
740 0);
741
742 for (s = DECL_TEMPLATE_SPECIALIZATIONS (tmpl);
743 s != NULL_TREE;
744 s = TREE_CHAIN (s))
745 if (comp_template_args (TREE_PURPOSE (s), args))
746 return TREE_VALUE (s);
747
748 return NULL_TREE;
749 }
750
751 /* Like retrieve_speciailization, but for local declarations. */
752
753 static tree
754 retrieve_local_specialization (tmpl)
755 tree tmpl;
756 {
757 return (tree) htab_find (local_specializations, tmpl);
758 }
759
760 /* Returns non-zero iff DECL is a specialization of TMPL. */
761
762 int
763 is_specialization_of (decl, tmpl)
764 tree decl;
765 tree tmpl;
766 {
767 tree t;
768
769 if (TREE_CODE (decl) == FUNCTION_DECL)
770 {
771 for (t = decl;
772 t != NULL_TREE;
773 t = DECL_TEMPLATE_INFO (t) ? DECL_TI_TEMPLATE (t) : NULL_TREE)
774 if (t == tmpl)
775 return 1;
776 }
777 else
778 {
779 my_friendly_assert (TREE_CODE (decl) == TYPE_DECL, 0);
780
781 for (t = TREE_TYPE (decl);
782 t != NULL_TREE;
783 t = CLASSTYPE_USE_TEMPLATE (t)
784 ? TREE_TYPE (CLASSTYPE_TI_TEMPLATE (t)) : NULL_TREE)
785 if (same_type_ignoring_top_level_qualifiers_p (t, TREE_TYPE (tmpl)))
786 return 1;
787 }
788
789 return 0;
790 }
791
792 /* Register the specialization SPEC as a specialization of TMPL with
793 the indicated ARGS. Returns SPEC, or an equivalent prior
794 declaration, if available. */
795
796 static tree
797 register_specialization (spec, tmpl, args)
798 tree spec;
799 tree tmpl;
800 tree args;
801 {
802 tree s;
803
804 my_friendly_assert (TREE_CODE (tmpl) == TEMPLATE_DECL, 0);
805
806 if (TREE_CODE (spec) == FUNCTION_DECL
807 && uses_template_parms (DECL_TI_ARGS (spec)))
808 /* This is the FUNCTION_DECL for a partial instantiation. Don't
809 register it; we want the corresponding TEMPLATE_DECL instead.
810 We use `uses_template_parms (DECL_TI_ARGS (spec))' rather than
811 the more obvious `uses_template_parms (spec)' to avoid problems
812 with default function arguments. In particular, given
813 something like this:
814
815 template <class T> void f(T t1, T t = T())
816
817 the default argument expression is not substituted for in an
818 instantiation unless and until it is actually needed. */
819 return spec;
820
821 /* There should be as many levels of arguments as there are
822 levels of parameters. */
823 my_friendly_assert (TMPL_ARGS_DEPTH (args)
824 == TMPL_PARMS_DEPTH (DECL_TEMPLATE_PARMS (tmpl)),
825 0);
826
827 for (s = DECL_TEMPLATE_SPECIALIZATIONS (tmpl);
828 s != NULL_TREE;
829 s = TREE_CHAIN (s))
830 {
831 tree fn = TREE_VALUE (s);
832
833 /* We can sometimes try to re-register a specialization that we've
834 already got. In particular, regenerate_decl_from_template
835 calls duplicate_decls which will update the specialization
836 list. But, we'll still get called again here anyhow. It's
837 more convenient to simply allow this than to try to prevent it. */
838 if (fn == spec)
839 return spec;
840 else if (comp_template_args (TREE_PURPOSE (s), args))
841 {
842 if (DECL_TEMPLATE_SPECIALIZATION (spec))
843 {
844 if (DECL_TEMPLATE_INSTANTIATION (fn))
845 {
846 if (TREE_USED (fn)
847 || DECL_EXPLICIT_INSTANTIATION (fn))
848 {
849 cp_error ("specialization of %D after instantiation",
850 fn);
851 return spec;
852 }
853 else
854 {
855 /* This situation should occur only if the first
856 specialization is an implicit instantiation,
857 the second is an explicit specialization, and
858 the implicit instantiation has not yet been
859 used. That situation can occur if we have
860 implicitly instantiated a member function and
861 then specialized it later.
862
863 We can also wind up here if a friend
864 declaration that looked like an instantiation
865 turns out to be a specialization:
866
867 template <class T> void foo(T);
868 class S { friend void foo<>(int) };
869 template <> void foo(int);
870
871 We transform the existing DECL in place so that
872 any pointers to it become pointers to the
873 updated declaration.
874
875 If there was a definition for the template, but
876 not for the specialization, we want this to
877 look as if there is no definition, and vice
878 versa. */
879 DECL_INITIAL (fn) = NULL_TREE;
880 duplicate_decls (spec, fn);
881
882 return fn;
883 }
884 }
885 else if (DECL_TEMPLATE_SPECIALIZATION (fn))
886 {
887 duplicate_decls (spec, fn);
888 return fn;
889 }
890 }
891 }
892 }
893
894 DECL_TEMPLATE_SPECIALIZATIONS (tmpl)
895 = tree_cons (args, spec, DECL_TEMPLATE_SPECIALIZATIONS (tmpl));
896
897 return spec;
898 }
899
900 /* Unregister the specialization SPEC as a specialization of TMPL.
901 Returns nonzero if the SPEC was listed as a specialization of
902 TMPL. */
903
904 static int
905 unregister_specialization (spec, tmpl)
906 tree spec;
907 tree tmpl;
908 {
909 tree* s;
910
911 for (s = &DECL_TEMPLATE_SPECIALIZATIONS (tmpl);
912 *s != NULL_TREE;
913 s = &TREE_CHAIN (*s))
914 if (TREE_VALUE (*s) == spec)
915 {
916 *s = TREE_CHAIN (*s);
917 return 1;
918 }
919
920 return 0;
921 }
922
923 /* Like register_specialization, but for local declarations. We are
924 registering SPEC, an instantiation of TMPL. */
925
926 static tree
927 register_local_specialization (spec, tmpl)
928 tree spec;
929 tree tmpl;
930 {
931 void **slot;
932
933 slot = htab_find_slot (local_specializations, tmpl, INSERT);
934 *slot = spec;
935
936 return spec;
937 }
938
939 /* Print the list of candidate FNS in an error message. */
940
941 void
942 print_candidates (fns)
943 tree fns;
944 {
945 tree fn;
946
947 const char *str = "candidates are:";
948
949 for (fn = fns; fn != NULL_TREE; fn = TREE_CHAIN (fn))
950 {
951 tree f;
952
953 for (f = TREE_VALUE (fn); f; f = OVL_NEXT (f))
954 cp_error_at ("%s %+#D", str, OVL_CURRENT (f));
955 str = " ";
956 }
957 }
958
959 /* Returns the template (one of the functions given by TEMPLATE_ID)
960 which can be specialized to match the indicated DECL with the
961 explicit template args given in TEMPLATE_ID. The DECL may be
962 NULL_TREE if none is available. In that case, the functions in
963 TEMPLATE_ID are non-members.
964
965 If NEED_MEMBER_TEMPLATE is non-zero the function is known to be a
966 specialization of a member template.
967
968 The template args (those explicitly specified and those deduced)
969 are output in a newly created vector *TARGS_OUT.
970
971 If it is impossible to determine the result, an error message is
972 issued. The error_mark_node is returned to indicate failure. */
973
974 static tree
975 determine_specialization (template_id, decl, targs_out,
976 need_member_template)
977 tree template_id;
978 tree decl;
979 tree* targs_out;
980 int need_member_template;
981 {
982 tree fns;
983 tree targs;
984 tree explicit_targs;
985 tree candidates = NULL_TREE;
986 tree templates = NULL_TREE;
987
988 *targs_out = NULL_TREE;
989
990 if (template_id == error_mark_node)
991 return error_mark_node;
992
993 fns = TREE_OPERAND (template_id, 0);
994 explicit_targs = TREE_OPERAND (template_id, 1);
995
996 if (fns == error_mark_node)
997 return error_mark_node;
998
999 /* Check for baselinks. */
1000 if (BASELINK_P (fns))
1001 fns = TREE_VALUE (fns);
1002
1003 if (!is_overloaded_fn (fns))
1004 {
1005 cp_error ("`%D' is not a function template", fns);
1006 return error_mark_node;
1007 }
1008
1009 for (; fns; fns = OVL_NEXT (fns))
1010 {
1011 tree tmpl;
1012
1013 tree fn = OVL_CURRENT (fns);
1014
1015 if (TREE_CODE (fn) == TEMPLATE_DECL)
1016 /* DECL might be a specialization of FN. */
1017 tmpl = fn;
1018 else if (need_member_template)
1019 /* FN is an ordinary member function, and we need a
1020 specialization of a member template. */
1021 continue;
1022 else if (TREE_CODE (fn) != FUNCTION_DECL)
1023 /* We can get IDENTIFIER_NODEs here in certain erroneous
1024 cases. */
1025 continue;
1026 else if (!DECL_FUNCTION_MEMBER_P (fn))
1027 /* This is just an ordinary non-member function. Nothing can
1028 be a specialization of that. */
1029 continue;
1030 else
1031 {
1032 tree decl_arg_types;
1033
1034 /* This is an ordinary member function. However, since
1035 we're here, we can assume it's enclosing class is a
1036 template class. For example,
1037
1038 template <typename T> struct S { void f(); };
1039 template <> void S<int>::f() {}
1040
1041 Here, S<int>::f is a non-template, but S<int> is a
1042 template class. If FN has the same type as DECL, we
1043 might be in business. */
1044 if (!same_type_p (TREE_TYPE (TREE_TYPE (decl)),
1045 TREE_TYPE (TREE_TYPE (fn))))
1046 /* The return types differ. */
1047 continue;
1048
1049 /* Adjust the type of DECL in case FN is a static member. */
1050 decl_arg_types = TYPE_ARG_TYPES (TREE_TYPE (decl));
1051 if (DECL_STATIC_FUNCTION_P (fn)
1052 && DECL_NONSTATIC_MEMBER_FUNCTION_P (decl))
1053 decl_arg_types = TREE_CHAIN (decl_arg_types);
1054
1055 if (compparms (TYPE_ARG_TYPES (TREE_TYPE (fn)),
1056 decl_arg_types))
1057 /* They match! */
1058 candidates = tree_cons (NULL_TREE, fn, candidates);
1059
1060 continue;
1061 }
1062
1063 /* See whether this function might be a specialization of this
1064 template. */
1065 targs = get_bindings (tmpl, decl, explicit_targs);
1066
1067 if (!targs)
1068 /* We cannot deduce template arguments that when used to
1069 specialize TMPL will produce DECL. */
1070 continue;
1071
1072 /* Save this template, and the arguments deduced. */
1073 templates = tree_cons (targs, tmpl, templates);
1074 }
1075
1076 if (templates && TREE_CHAIN (templates))
1077 {
1078 /* We have:
1079
1080 [temp.expl.spec]
1081
1082 It is possible for a specialization with a given function
1083 signature to be instantiated from more than one function
1084 template. In such cases, explicit specification of the
1085 template arguments must be used to uniquely identify the
1086 function template specialization being specialized.
1087
1088 Note that here, there's no suggestion that we're supposed to
1089 determine which of the candidate templates is most
1090 specialized. However, we, also have:
1091
1092 [temp.func.order]
1093
1094 Partial ordering of overloaded function template
1095 declarations is used in the following contexts to select
1096 the function template to which a function template
1097 specialization refers:
1098
1099 -- when an explicit specialization refers to a function
1100 template.
1101
1102 So, we do use the partial ordering rules, at least for now.
1103 This extension can only serve to make illegal programs legal,
1104 so it's safe. And, there is strong anecdotal evidence that
1105 the committee intended the partial ordering rules to apply;
1106 the EDG front-end has that behavior, and John Spicer claims
1107 that the committee simply forgot to delete the wording in
1108 [temp.expl.spec]. */
1109 tree tmpl = most_specialized (templates, decl, explicit_targs);
1110 if (tmpl && tmpl != error_mark_node)
1111 {
1112 targs = get_bindings (tmpl, decl, explicit_targs);
1113 templates = tree_cons (targs, tmpl, NULL_TREE);
1114 }
1115 }
1116
1117 if (templates == NULL_TREE && candidates == NULL_TREE)
1118 {
1119 cp_error_at ("template-id `%D' for `%+D' does not match any template declaration",
1120 template_id, decl);
1121 return error_mark_node;
1122 }
1123 else if ((templates && TREE_CHAIN (templates))
1124 || (candidates && TREE_CHAIN (candidates))
1125 || (templates && candidates))
1126 {
1127 cp_error_at ("ambiguous template specialization `%D' for `%+D'",
1128 template_id, decl);
1129 chainon (candidates, templates);
1130 print_candidates (candidates);
1131 return error_mark_node;
1132 }
1133
1134 /* We have one, and exactly one, match. */
1135 if (candidates)
1136 {
1137 /* It was a specialization of an ordinary member function in a
1138 template class. */
1139 *targs_out = copy_node (DECL_TI_ARGS (TREE_VALUE (candidates)));
1140 return DECL_TI_TEMPLATE (TREE_VALUE (candidates));
1141 }
1142
1143 /* It was a specialization of a template. */
1144 targs = DECL_TI_ARGS (DECL_TEMPLATE_RESULT (TREE_VALUE (templates)));
1145 if (TMPL_ARGS_HAVE_MULTIPLE_LEVELS (targs))
1146 {
1147 *targs_out = copy_node (targs);
1148 SET_TMPL_ARGS_LEVEL (*targs_out,
1149 TMPL_ARGS_DEPTH (*targs_out),
1150 TREE_PURPOSE (templates));
1151 }
1152 else
1153 *targs_out = TREE_PURPOSE (templates);
1154 return TREE_VALUE (templates);
1155 }
1156
1157 /* Check to see if the function just declared, as indicated in
1158 DECLARATOR, and in DECL, is a specialization of a function
1159 template. We may also discover that the declaration is an explicit
1160 instantiation at this point.
1161
1162 Returns DECL, or an equivalent declaration that should be used
1163 instead if all goes well. Issues an error message if something is
1164 amiss. Returns error_mark_node if the error is not easily
1165 recoverable.
1166
1167 FLAGS is a bitmask consisting of the following flags:
1168
1169 2: The function has a definition.
1170 4: The function is a friend.
1171
1172 The TEMPLATE_COUNT is the number of references to qualifying
1173 template classes that appeared in the name of the function. For
1174 example, in
1175
1176 template <class T> struct S { void f(); };
1177 void S<int>::f();
1178
1179 the TEMPLATE_COUNT would be 1. However, explicitly specialized
1180 classes are not counted in the TEMPLATE_COUNT, so that in
1181
1182 template <class T> struct S {};
1183 template <> struct S<int> { void f(); }
1184 template <> void S<int>::f();
1185
1186 the TEMPLATE_COUNT would be 0. (Note that this declaration is
1187 illegal; there should be no template <>.)
1188
1189 If the function is a specialization, it is marked as such via
1190 DECL_TEMPLATE_SPECIALIZATION. Furthermore, its DECL_TEMPLATE_INFO
1191 is set up correctly, and it is added to the list of specializations
1192 for that template. */
1193
1194 tree
1195 check_explicit_specialization (declarator, decl, template_count, flags)
1196 tree declarator;
1197 tree decl;
1198 int template_count;
1199 int flags;
1200 {
1201 int have_def = flags & 2;
1202 int is_friend = flags & 4;
1203 int specialization = 0;
1204 int explicit_instantiation = 0;
1205 int member_specialization = 0;
1206 tree ctype = DECL_CLASS_CONTEXT (decl);
1207 tree dname = DECL_NAME (decl);
1208 tmpl_spec_kind tsk;
1209
1210 tsk = current_tmpl_spec_kind (template_count);
1211
1212 switch (tsk)
1213 {
1214 case tsk_none:
1215 if (processing_specialization)
1216 {
1217 specialization = 1;
1218 SET_DECL_TEMPLATE_SPECIALIZATION (decl);
1219 }
1220 else if (TREE_CODE (declarator) == TEMPLATE_ID_EXPR)
1221 {
1222 if (is_friend)
1223 /* This could be something like:
1224
1225 template <class T> void f(T);
1226 class S { friend void f<>(int); } */
1227 specialization = 1;
1228 else
1229 {
1230 /* This case handles bogus declarations like template <>
1231 template <class T> void f<int>(); */
1232
1233 cp_error ("template-id `%D' in declaration of primary template",
1234 declarator);
1235 return decl;
1236 }
1237 }
1238 break;
1239
1240 case tsk_invalid_member_spec:
1241 /* The error has already been reported in
1242 check_specialization_scope. */
1243 return error_mark_node;
1244
1245 case tsk_invalid_expl_inst:
1246 cp_error ("template parameter list used in explicit instantiation");
1247
1248 /* Fall through. */
1249
1250 case tsk_expl_inst:
1251 if (have_def)
1252 cp_error ("definition provided for explicit instantiation");
1253
1254 explicit_instantiation = 1;
1255 break;
1256
1257 case tsk_excessive_parms:
1258 cp_error ("too many template parameter lists in declaration of `%D'",
1259 decl);
1260 return error_mark_node;
1261
1262 /* Fall through. */
1263 case tsk_expl_spec:
1264 SET_DECL_TEMPLATE_SPECIALIZATION (decl);
1265 if (ctype)
1266 member_specialization = 1;
1267 else
1268 specialization = 1;
1269 break;
1270
1271 case tsk_insufficient_parms:
1272 if (template_header_count)
1273 {
1274 cp_error("too few template parameter lists in declaration of `%D'",
1275 decl);
1276 return decl;
1277 }
1278 else if (ctype != NULL_TREE
1279 && !TYPE_BEING_DEFINED (ctype)
1280 && CLASSTYPE_TEMPLATE_INSTANTIATION (ctype)
1281 && !is_friend)
1282 {
1283 /* For backwards compatibility, we accept:
1284
1285 template <class T> struct S { void f(); };
1286 void S<int>::f() {} // Missing template <>
1287
1288 That used to be legal C++. */
1289 if (pedantic)
1290 cp_pedwarn
1291 ("explicit specialization not preceded by `template <>'");
1292 specialization = 1;
1293 SET_DECL_TEMPLATE_SPECIALIZATION (decl);
1294 }
1295 break;
1296
1297 case tsk_template:
1298 if (TREE_CODE (declarator) == TEMPLATE_ID_EXPR)
1299 {
1300 /* This case handles bogus declarations like template <>
1301 template <class T> void f<int>(); */
1302
1303 if (uses_template_parms (declarator))
1304 cp_error ("partial specialization `%D' of function template",
1305 declarator);
1306 else
1307 cp_error ("template-id `%D' in declaration of primary template",
1308 declarator);
1309 return decl;
1310 }
1311
1312 if (ctype && CLASSTYPE_TEMPLATE_INSTANTIATION (ctype))
1313 /* This is a specialization of a member template, without
1314 specialization the containing class. Something like:
1315
1316 template <class T> struct S {
1317 template <class U> void f (U);
1318 };
1319 template <> template <class U> void S<int>::f(U) {}
1320
1321 That's a specialization -- but of the entire template. */
1322 specialization = 1;
1323 break;
1324
1325 default:
1326 my_friendly_abort (20000309);
1327 }
1328
1329 if (specialization || member_specialization)
1330 {
1331 tree t = TYPE_ARG_TYPES (TREE_TYPE (decl));
1332 for (; t; t = TREE_CHAIN (t))
1333 if (TREE_PURPOSE (t))
1334 {
1335 cp_pedwarn
1336 ("default argument specified in explicit specialization");
1337 break;
1338 }
1339 if (current_lang_name == lang_name_c)
1340 cp_error ("template specialization with C linkage");
1341 }
1342
1343 if (specialization || member_specialization || explicit_instantiation)
1344 {
1345 tree tmpl = NULL_TREE;
1346 tree targs = NULL_TREE;
1347
1348 /* Make sure that the declarator is a TEMPLATE_ID_EXPR. */
1349 if (TREE_CODE (declarator) != TEMPLATE_ID_EXPR)
1350 {
1351 tree fns;
1352
1353 my_friendly_assert (TREE_CODE (declarator) == IDENTIFIER_NODE,
1354 0);
1355 if (!ctype)
1356 fns = IDENTIFIER_NAMESPACE_VALUE (dname);
1357 else
1358 fns = dname;
1359
1360 declarator =
1361 lookup_template_function (fns, NULL_TREE);
1362 }
1363
1364 if (declarator == error_mark_node)
1365 return error_mark_node;
1366
1367 if (ctype != NULL_TREE && TYPE_BEING_DEFINED (ctype))
1368 {
1369 if (!explicit_instantiation)
1370 /* A specialization in class scope. This is illegal,
1371 but the error will already have been flagged by
1372 check_specialization_scope. */
1373 return error_mark_node;
1374 else
1375 {
1376 /* It's not legal to write an explicit instantiation in
1377 class scope, e.g.:
1378
1379 class C { template void f(); }
1380
1381 This case is caught by the parser. However, on
1382 something like:
1383
1384 template class C { void f(); };
1385
1386 (which is illegal) we can get here. The error will be
1387 issued later. */
1388 ;
1389 }
1390
1391 return decl;
1392 }
1393 else if (TREE_CODE (TREE_OPERAND (declarator, 0)) == LOOKUP_EXPR)
1394 {
1395 /* A friend declaration. We can't do much, because we don't
1396 know what this resolves to, yet. */
1397 my_friendly_assert (is_friend != 0, 0);
1398 my_friendly_assert (!explicit_instantiation, 0);
1399 SET_DECL_IMPLICIT_INSTANTIATION (decl);
1400 return decl;
1401 }
1402 else if (ctype != NULL_TREE
1403 && (TREE_CODE (TREE_OPERAND (declarator, 0)) ==
1404 IDENTIFIER_NODE))
1405 {
1406 /* Find the list of functions in ctype that have the same
1407 name as the declared function. */
1408 tree name = TREE_OPERAND (declarator, 0);
1409 tree fns = NULL_TREE;
1410 int idx;
1411
1412 if (name == constructor_name (ctype)
1413 || name == constructor_name_full (ctype))
1414 {
1415 int is_constructor = DECL_CONSTRUCTOR_P (decl);
1416
1417 if (is_constructor ? !TYPE_HAS_CONSTRUCTOR (ctype)
1418 : !TYPE_HAS_DESTRUCTOR (ctype))
1419 {
1420 /* From [temp.expl.spec]:
1421
1422 If such an explicit specialization for the member
1423 of a class template names an implicitly-declared
1424 special member function (clause _special_), the
1425 program is ill-formed.
1426
1427 Similar language is found in [temp.explicit]. */
1428 cp_error ("specialization of implicitly-declared special member function");
1429 return error_mark_node;
1430 }
1431
1432 name = is_constructor ? ctor_identifier : dtor_identifier;
1433 }
1434
1435 if (!DECL_CONV_FN_P (decl))
1436 {
1437 idx = lookup_fnfields_1 (ctype, name);
1438 if (idx >= 0)
1439 fns = TREE_VEC_ELT (CLASSTYPE_METHOD_VEC (ctype), idx);
1440 }
1441 else
1442 {
1443 tree methods;
1444
1445 /* For a type-conversion operator, we cannot do a
1446 name-based lookup. We might be looking for `operator
1447 int' which will be a specialization of `operator T'.
1448 So, we find *all* the conversion operators, and then
1449 select from them. */
1450 fns = NULL_TREE;
1451
1452 methods = CLASSTYPE_METHOD_VEC (ctype);
1453 if (methods)
1454 for (idx = 2; idx < TREE_VEC_LENGTH (methods); ++idx)
1455 {
1456 tree ovl = TREE_VEC_ELT (methods, idx);
1457
1458 if (!ovl || !DECL_CONV_FN_P (OVL_CURRENT (ovl)))
1459 /* There are no more conversion functions. */
1460 break;
1461
1462 /* Glue all these conversion functions together
1463 with those we already have. */
1464 for (; ovl; ovl = OVL_NEXT (ovl))
1465 fns = ovl_cons (OVL_CURRENT (ovl), fns);
1466 }
1467 }
1468
1469 if (fns == NULL_TREE)
1470 {
1471 cp_error ("no member function `%D' declared in `%T'",
1472 name, ctype);
1473 return error_mark_node;
1474 }
1475 else
1476 TREE_OPERAND (declarator, 0) = fns;
1477 }
1478
1479 /* Figure out what exactly is being specialized at this point.
1480 Note that for an explicit instantiation, even one for a
1481 member function, we cannot tell apriori whether the
1482 instantiation is for a member template, or just a member
1483 function of a template class. Even if a member template is
1484 being instantiated, the member template arguments may be
1485 elided if they can be deduced from the rest of the
1486 declaration. */
1487 tmpl = determine_specialization (declarator, decl,
1488 &targs,
1489 member_specialization);
1490
1491 if (!tmpl || tmpl == error_mark_node)
1492 /* We couldn't figure out what this declaration was
1493 specializing. */
1494 return error_mark_node;
1495 else
1496 {
1497 tree gen_tmpl = most_general_template (tmpl);
1498
1499 if (explicit_instantiation)
1500 {
1501 /* We don't set DECL_EXPLICIT_INSTANTIATION here; that
1502 is done by do_decl_instantiation later. */
1503
1504 int arg_depth = TMPL_ARGS_DEPTH (targs);
1505 int parm_depth = TMPL_PARMS_DEPTH (DECL_TEMPLATE_PARMS (tmpl));
1506
1507 if (arg_depth > parm_depth)
1508 {
1509 /* If TMPL is not the most general template (for
1510 example, if TMPL is a friend template that is
1511 injected into namespace scope), then there will
1512 be too many levels fo TARGS. Remove some of them
1513 here. */
1514 int i;
1515 tree new_targs;
1516
1517 new_targs = make_tree_vec (parm_depth);
1518 for (i = arg_depth - parm_depth; i < arg_depth; ++i)
1519 TREE_VEC_ELT (new_targs, i - (arg_depth - parm_depth))
1520 = TREE_VEC_ELT (targs, i);
1521 targs = new_targs;
1522 }
1523
1524 return instantiate_template (tmpl, targs);
1525 }
1526
1527 /* If this is a specialization of a member template of a
1528 template class. In we want to return the TEMPLATE_DECL,
1529 not the specialization of it. */
1530 if (tsk == tsk_template)
1531 {
1532 SET_DECL_TEMPLATE_SPECIALIZATION (tmpl);
1533 DECL_INITIAL (DECL_TEMPLATE_RESULT (tmpl)) = NULL_TREE;
1534 return tmpl;
1535 }
1536
1537 /* If we though that the DECL was a member function, but it
1538 turns out to be specializing a static member function,
1539 make DECL a static member function as well. */
1540 if (DECL_STATIC_FUNCTION_P (tmpl)
1541 && DECL_NONSTATIC_MEMBER_FUNCTION_P (decl))
1542 {
1543 revert_static_member_fn (decl);
1544 last_function_parms = TREE_CHAIN (last_function_parms);
1545 }
1546
1547 /* Set up the DECL_TEMPLATE_INFO for DECL. */
1548 DECL_TEMPLATE_INFO (decl) = tree_cons (tmpl, targs, NULL_TREE);
1549
1550 /* Mangle the function name appropriately. Note that we do
1551 not mangle specializations of non-template member
1552 functions of template classes, e.g. with
1553
1554 template <class T> struct S { void f(); }
1555
1556 and given the specialization
1557
1558 template <> void S<int>::f() {}
1559
1560 we do not mangle S<int>::f() here. That's because it's
1561 just an ordinary member function and doesn't need special
1562 treatment. We do this here so that the ordinary,
1563 non-template, name-mangling algorithm will not be used
1564 later. */
1565 if ((is_member_template (tmpl) || ctype == NULL_TREE)
1566 && name_mangling_version >= 1)
1567 set_mangled_name_for_template_decl (decl);
1568
1569 if (is_friend && !have_def)
1570 /* This is not really a declaration of a specialization.
1571 It's just the name of an instantiation. But, it's not
1572 a request for an instantiation, either. */
1573 SET_DECL_IMPLICIT_INSTANTIATION (decl);
1574
1575 /* Register this specialization so that we can find it
1576 again. */
1577 decl = register_specialization (decl, gen_tmpl, targs);
1578 }
1579 }
1580
1581 return decl;
1582 }
1583
1584 /* TYPE is being declared. Verify that the use of template headers
1585 and such is reasonable. Issue error messages if not. */
1586
1587 void
1588 maybe_check_template_type (type)
1589 tree type;
1590 {
1591 if (template_header_count)
1592 {
1593 /* We are in the scope of some `template <...>' header. */
1594
1595 int context_depth
1596 = template_class_depth_real (TYPE_CONTEXT (type),
1597 /*count_specializations=*/1);
1598
1599 if (template_header_count <= context_depth)
1600 /* This is OK; the template headers are for the context. We
1601 are actually too lenient here; like
1602 check_explicit_specialization we should consider the number
1603 of template types included in the actual declaration. For
1604 example,
1605
1606 template <class T> struct S {
1607 template <class U> template <class V>
1608 struct I {};
1609 };
1610
1611 is illegal, but:
1612
1613 template <class T> struct S {
1614 template <class U> struct I;
1615 };
1616
1617 template <class T> template <class U.
1618 struct S<T>::I {};
1619
1620 is not. */
1621 ;
1622 else if (template_header_count > context_depth + 1)
1623 /* There are two many template parameter lists. */
1624 cp_error ("too many template parameter lists in declaration of `%T'", type);
1625 }
1626 }
1627
1628 /* Returns 1 iff PARMS1 and PARMS2 are identical sets of template
1629 parameters. These are represented in the same format used for
1630 DECL_TEMPLATE_PARMS. */
1631
1632 int comp_template_parms (parms1, parms2)
1633 tree parms1;
1634 tree parms2;
1635 {
1636 tree p1;
1637 tree p2;
1638
1639 if (parms1 == parms2)
1640 return 1;
1641
1642 for (p1 = parms1, p2 = parms2;
1643 p1 != NULL_TREE && p2 != NULL_TREE;
1644 p1 = TREE_CHAIN (p1), p2 = TREE_CHAIN (p2))
1645 {
1646 tree t1 = TREE_VALUE (p1);
1647 tree t2 = TREE_VALUE (p2);
1648 int i;
1649
1650 my_friendly_assert (TREE_CODE (t1) == TREE_VEC, 0);
1651 my_friendly_assert (TREE_CODE (t2) == TREE_VEC, 0);
1652
1653 if (TREE_VEC_LENGTH (t1) != TREE_VEC_LENGTH (t2))
1654 return 0;
1655
1656 for (i = 0; i < TREE_VEC_LENGTH (t2); ++i)
1657 {
1658 tree parm1 = TREE_VALUE (TREE_VEC_ELT (t1, i));
1659 tree parm2 = TREE_VALUE (TREE_VEC_ELT (t2, i));
1660
1661 if (TREE_CODE (parm1) != TREE_CODE (parm2))
1662 return 0;
1663
1664 if (TREE_CODE (parm1) == TEMPLATE_TYPE_PARM)
1665 continue;
1666 else if (!same_type_p (TREE_TYPE (parm1), TREE_TYPE (parm2)))
1667 return 0;
1668 }
1669 }
1670
1671 if ((p1 != NULL_TREE) != (p2 != NULL_TREE))
1672 /* One set of parameters has more parameters lists than the
1673 other. */
1674 return 0;
1675
1676 return 1;
1677 }
1678
1679 /* Complain if DECL shadows a template parameter.
1680
1681 [temp.local]: A template-parameter shall not be redeclared within its
1682 scope (including nested scopes). */
1683
1684 void
1685 check_template_shadow (decl)
1686 tree decl;
1687 {
1688 tree olddecl;
1689
1690 /* If we're not in a template, we can't possibly shadow a template
1691 parameter. */
1692 if (!current_template_parms)
1693 return;
1694
1695 /* Figure out what we're shadowing. */
1696 if (TREE_CODE (decl) == OVERLOAD)
1697 decl = OVL_CURRENT (decl);
1698 olddecl = IDENTIFIER_VALUE (DECL_NAME (decl));
1699
1700 /* If there's no previous binding for this name, we're not shadowing
1701 anything, let alone a template parameter. */
1702 if (!olddecl)
1703 return;
1704
1705 /* If we're not shadowing a template parameter, we're done. Note
1706 that OLDDECL might be an OVERLOAD (or perhaps even an
1707 ERROR_MARK), so we can't just blithely assume it to be a _DECL
1708 node. */
1709 if (!DECL_P (olddecl) || !DECL_TEMPLATE_PARM_P (olddecl))
1710 return;
1711
1712 /* We check for decl != olddecl to avoid bogus errors for using a
1713 name inside a class. We check TPFI to avoid duplicate errors for
1714 inline member templates. */
1715 if (decl == olddecl
1716 || TEMPLATE_PARMS_FOR_INLINE (current_template_parms))
1717 return;
1718
1719 cp_error_at ("declaration of `%#D'", decl);
1720 cp_error_at (" shadows template parm `%#D'", olddecl);
1721 }
1722
1723 /* Return a new TEMPLATE_PARM_INDEX with the indicated INDEX, LEVEL,
1724 ORIG_LEVEL, DECL, and TYPE. */
1725
1726 static tree
1727 build_template_parm_index (index, level, orig_level, decl, type)
1728 int index;
1729 int level;
1730 int orig_level;
1731 tree decl;
1732 tree type;
1733 {
1734 tree t = make_node (TEMPLATE_PARM_INDEX);
1735 TEMPLATE_PARM_IDX (t) = index;
1736 TEMPLATE_PARM_LEVEL (t) = level;
1737 TEMPLATE_PARM_ORIG_LEVEL (t) = orig_level;
1738 TEMPLATE_PARM_DECL (t) = decl;
1739 TREE_TYPE (t) = type;
1740
1741 return t;
1742 }
1743
1744 /* Return a TEMPLATE_PARM_INDEX, similar to INDEX, but whose
1745 TEMPLATE_PARM_LEVEL has been decreased by LEVELS. If such a
1746 TEMPLATE_PARM_INDEX already exists, it is returned; otherwise, a
1747 new one is created. */
1748
1749 static tree
1750 reduce_template_parm_level (index, type, levels)
1751 tree index;
1752 tree type;
1753 int levels;
1754 {
1755 if (TEMPLATE_PARM_DESCENDANTS (index) == NULL_TREE
1756 || (TEMPLATE_PARM_LEVEL (TEMPLATE_PARM_DESCENDANTS (index))
1757 != TEMPLATE_PARM_LEVEL (index) - levels))
1758 {
1759 tree decl
1760 = build_decl (TREE_CODE (TEMPLATE_PARM_DECL (index)),
1761 DECL_NAME (TEMPLATE_PARM_DECL (index)),
1762 type);
1763 tree t
1764 = build_template_parm_index (TEMPLATE_PARM_IDX (index),
1765 TEMPLATE_PARM_LEVEL (index) - levels,
1766 TEMPLATE_PARM_ORIG_LEVEL (index),
1767 decl, type);
1768 TEMPLATE_PARM_DESCENDANTS (index) = t;
1769
1770 /* Template template parameters need this. */
1771 DECL_TEMPLATE_PARMS (decl)
1772 = DECL_TEMPLATE_PARMS (TEMPLATE_PARM_DECL (index));
1773 }
1774
1775 return TEMPLATE_PARM_DESCENDANTS (index);
1776 }
1777
1778 /* Process information from new template parameter NEXT and append it to the
1779 LIST being built. */
1780
1781 tree
1782 process_template_parm (list, next)
1783 tree list, next;
1784 {
1785 tree parm;
1786 tree decl = 0;
1787 tree defval;
1788 int is_type, idx;
1789
1790 parm = next;
1791 my_friendly_assert (TREE_CODE (parm) == TREE_LIST, 259);
1792 defval = TREE_PURPOSE (parm);
1793 parm = TREE_VALUE (parm);
1794 is_type = TREE_PURPOSE (parm) == class_type_node;
1795
1796 if (list)
1797 {
1798 tree p = TREE_VALUE (tree_last (list));
1799
1800 if (TREE_CODE (p) == TYPE_DECL || TREE_CODE (p) == TEMPLATE_DECL)
1801 idx = TEMPLATE_TYPE_IDX (TREE_TYPE (p));
1802 else
1803 idx = TEMPLATE_PARM_IDX (DECL_INITIAL (p));
1804 ++idx;
1805 }
1806 else
1807 idx = 0;
1808
1809 if (!is_type)
1810 {
1811 my_friendly_assert (TREE_CODE (TREE_PURPOSE (parm)) == TREE_LIST, 260);
1812 /* is a const-param */
1813 parm = grokdeclarator (TREE_VALUE (parm), TREE_PURPOSE (parm),
1814 PARM, 0, NULL_TREE);
1815
1816 /* [temp.param]
1817
1818 The top-level cv-qualifiers on the template-parameter are
1819 ignored when determining its type. */
1820 TREE_TYPE (parm) = TYPE_MAIN_VARIANT (TREE_TYPE (parm));
1821
1822 /* A template parameter is not modifiable. */
1823 TREE_READONLY (parm) = 1;
1824 if (IS_AGGR_TYPE (TREE_TYPE (parm))
1825 && TREE_CODE (TREE_TYPE (parm)) != TEMPLATE_TYPE_PARM
1826 && TREE_CODE (TREE_TYPE (parm)) != TYPENAME_TYPE)
1827 {
1828 cp_error ("`%#T' is not a valid type for a template constant parameter",
1829 TREE_TYPE (parm));
1830 if (DECL_NAME (parm) == NULL_TREE)
1831 error (" a template type parameter must begin with `class' or `typename'");
1832 TREE_TYPE (parm) = void_type_node;
1833 }
1834 else if (pedantic
1835 && (TREE_CODE (TREE_TYPE (parm)) == REAL_TYPE
1836 || TREE_CODE (TREE_TYPE (parm)) == COMPLEX_TYPE))
1837 cp_pedwarn ("`%T' is not a valid type for a template constant parameter",
1838 TREE_TYPE (parm));
1839 decl = build_decl (CONST_DECL, DECL_NAME (parm), TREE_TYPE (parm));
1840 DECL_INITIAL (parm) = DECL_INITIAL (decl)
1841 = build_template_parm_index (idx, processing_template_decl,
1842 processing_template_decl,
1843 decl, TREE_TYPE (parm));
1844 }
1845 else
1846 {
1847 tree t;
1848 parm = TREE_VALUE (parm);
1849
1850 if (parm && TREE_CODE (parm) == TEMPLATE_DECL)
1851 {
1852 t = make_aggr_type (TEMPLATE_TEMPLATE_PARM);
1853 /* This is for distinguishing between real templates and template
1854 template parameters */
1855 TREE_TYPE (parm) = t;
1856 TREE_TYPE (DECL_TEMPLATE_RESULT (parm)) = t;
1857 decl = parm;
1858 }
1859 else
1860 {
1861 t = make_aggr_type (TEMPLATE_TYPE_PARM);
1862 /* parm is either IDENTIFIER_NODE or NULL_TREE */
1863 decl = build_decl (TYPE_DECL, parm, t);
1864 }
1865
1866 TYPE_NAME (t) = decl;
1867 TYPE_STUB_DECL (t) = decl;
1868 parm = decl;
1869 TEMPLATE_TYPE_PARM_INDEX (t)
1870 = build_template_parm_index (idx, processing_template_decl,
1871 processing_template_decl,
1872 decl, TREE_TYPE (parm));
1873 }
1874 DECL_ARTIFICIAL (decl) = 1;
1875 SET_DECL_TEMPLATE_PARM_P (decl);
1876 pushdecl (decl);
1877 parm = build_tree_list (defval, parm);
1878 return chainon (list, parm);
1879 }
1880
1881 /* The end of a template parameter list has been reached. Process the
1882 tree list into a parameter vector, converting each parameter into a more
1883 useful form. Type parameters are saved as IDENTIFIER_NODEs, and others
1884 as PARM_DECLs. */
1885
1886 tree
1887 end_template_parm_list (parms)
1888 tree parms;
1889 {
1890 int nparms;
1891 tree parm;
1892 tree saved_parmlist = make_tree_vec (list_length (parms));
1893
1894 current_template_parms
1895 = tree_cons (build_int_2 (0, processing_template_decl),
1896 saved_parmlist, current_template_parms);
1897
1898 for (parm = parms, nparms = 0;
1899 parm;
1900 parm = TREE_CHAIN (parm), nparms++)
1901 TREE_VEC_ELT (saved_parmlist, nparms) = parm;
1902
1903 --processing_template_parmlist;
1904
1905 return saved_parmlist;
1906 }
1907
1908 /* end_template_decl is called after a template declaration is seen. */
1909
1910 void
1911 end_template_decl ()
1912 {
1913 reset_specialization ();
1914
1915 if (! processing_template_decl)
1916 return;
1917
1918 /* This matches the pushlevel in begin_template_parm_list. */
1919 finish_scope ();
1920
1921 --processing_template_decl;
1922 current_template_parms = TREE_CHAIN (current_template_parms);
1923 }
1924
1925 /* Given a template argument vector containing the template PARMS.
1926 The innermost PARMS are given first. */
1927
1928 tree
1929 current_template_args ()
1930 {
1931 tree header;
1932 tree args = NULL_TREE;
1933 int length = TMPL_PARMS_DEPTH (current_template_parms);
1934 int l = length;
1935
1936 /* If there is only one level of template parameters, we do not
1937 create a TREE_VEC of TREE_VECs. Instead, we return a single
1938 TREE_VEC containing the arguments. */
1939 if (length > 1)
1940 args = make_tree_vec (length);
1941
1942 for (header = current_template_parms; header; header = TREE_CHAIN (header))
1943 {
1944 tree a = copy_node (TREE_VALUE (header));
1945 int i;
1946
1947 TREE_TYPE (a) = NULL_TREE;
1948 for (i = TREE_VEC_LENGTH (a) - 1; i >= 0; --i)
1949 {
1950 tree t = TREE_VEC_ELT (a, i);
1951
1952 /* T will be a list if we are called from within a
1953 begin/end_template_parm_list pair, but a vector directly
1954 if within a begin/end_member_template_processing pair. */
1955 if (TREE_CODE (t) == TREE_LIST)
1956 {
1957 t = TREE_VALUE (t);
1958
1959 if (TREE_CODE (t) == TYPE_DECL
1960 || TREE_CODE (t) == TEMPLATE_DECL)
1961 t = TREE_TYPE (t);
1962 else
1963 t = DECL_INITIAL (t);
1964 TREE_VEC_ELT (a, i) = t;
1965 }
1966 }
1967
1968 if (length > 1)
1969 TREE_VEC_ELT (args, --l) = a;
1970 else
1971 args = a;
1972 }
1973
1974 return args;
1975 }
1976
1977 /* Return a TEMPLATE_DECL corresponding to DECL, using the indicated
1978 template PARMS. Used by push_template_decl below. */
1979
1980 static tree
1981 build_template_decl (decl, parms)
1982 tree decl;
1983 tree parms;
1984 {
1985 tree tmpl = build_lang_decl (TEMPLATE_DECL, DECL_NAME (decl), NULL_TREE);
1986 DECL_TEMPLATE_PARMS (tmpl) = parms;
1987 DECL_CONTEXT (tmpl) = DECL_CONTEXT (decl);
1988 if (DECL_LANG_SPECIFIC (decl))
1989 {
1990 DECL_VIRTUAL_CONTEXT (tmpl) = DECL_VIRTUAL_CONTEXT (decl);
1991 DECL_STATIC_FUNCTION_P (tmpl) = DECL_STATIC_FUNCTION_P (decl);
1992 DECL_CONSTRUCTOR_P (tmpl) = DECL_CONSTRUCTOR_P (decl);
1993 DECL_NONCONVERTING_P (tmpl) = DECL_NONCONVERTING_P (decl);
1994 DECL_ASSIGNMENT_OPERATOR_P (tmpl) = DECL_ASSIGNMENT_OPERATOR_P (decl);
1995 if (DECL_OVERLOADED_OPERATOR_P (decl))
1996 SET_OVERLOADED_OPERATOR_CODE (tmpl,
1997 DECL_OVERLOADED_OPERATOR_P (decl));
1998 }
1999
2000 return tmpl;
2001 }
2002
2003 struct template_parm_data
2004 {
2005 /* The level of the template parameters we are currently
2006 processing. */
2007 int level;
2008
2009 /* The index of the specialization argument we are currently
2010 processing. */
2011 int current_arg;
2012
2013 /* An array whose size is the number of template parameters. The
2014 elements are non-zero if the parameter has been used in any one
2015 of the arguments processed so far. */
2016 int* parms;
2017
2018 /* An array whose size is the number of template arguments. The
2019 elements are non-zero if the argument makes use of template
2020 parameters of this level. */
2021 int* arg_uses_template_parms;
2022 };
2023
2024 /* Subroutine of push_template_decl used to see if each template
2025 parameter in a partial specialization is used in the explicit
2026 argument list. If T is of the LEVEL given in DATA (which is
2027 treated as a template_parm_data*), then DATA->PARMS is marked
2028 appropriately. */
2029
2030 static int
2031 mark_template_parm (t, data)
2032 tree t;
2033 void* data;
2034 {
2035 int level;
2036 int idx;
2037 struct template_parm_data* tpd = (struct template_parm_data*) data;
2038
2039 if (TREE_CODE (t) == TEMPLATE_PARM_INDEX)
2040 {
2041 level = TEMPLATE_PARM_LEVEL (t);
2042 idx = TEMPLATE_PARM_IDX (t);
2043 }
2044 else
2045 {
2046 level = TEMPLATE_TYPE_LEVEL (t);
2047 idx = TEMPLATE_TYPE_IDX (t);
2048 }
2049
2050 if (level == tpd->level)
2051 {
2052 tpd->parms[idx] = 1;
2053 tpd->arg_uses_template_parms[tpd->current_arg] = 1;
2054 }
2055
2056 /* Return zero so that for_each_template_parm will continue the
2057 traversal of the tree; we want to mark *every* template parm. */
2058 return 0;
2059 }
2060
2061 /* Process the partial specialization DECL. */
2062
2063 static tree
2064 process_partial_specialization (decl)
2065 tree decl;
2066 {
2067 tree type = TREE_TYPE (decl);
2068 tree maintmpl = CLASSTYPE_TI_TEMPLATE (type);
2069 tree specargs = CLASSTYPE_TI_ARGS (type);
2070 tree inner_args = INNERMOST_TEMPLATE_ARGS (specargs);
2071 tree inner_parms = INNERMOST_TEMPLATE_PARMS (current_template_parms);
2072 tree main_inner_parms = DECL_INNERMOST_TEMPLATE_PARMS (maintmpl);
2073 int nargs = TREE_VEC_LENGTH (inner_args);
2074 int ntparms = TREE_VEC_LENGTH (inner_parms);
2075 int i;
2076 int did_error_intro = 0;
2077 struct template_parm_data tpd;
2078 struct template_parm_data tpd2;
2079
2080 /* We check that each of the template parameters given in the
2081 partial specialization is used in the argument list to the
2082 specialization. For example:
2083
2084 template <class T> struct S;
2085 template <class T> struct S<T*>;
2086
2087 The second declaration is OK because `T*' uses the template
2088 parameter T, whereas
2089
2090 template <class T> struct S<int>;
2091
2092 is no good. Even trickier is:
2093
2094 template <class T>
2095 struct S1
2096 {
2097 template <class U>
2098 struct S2;
2099 template <class U>
2100 struct S2<T>;
2101 };
2102
2103 The S2<T> declaration is actually illegal; it is a
2104 full-specialization. Of course,
2105
2106 template <class U>
2107 struct S2<T (*)(U)>;
2108
2109 or some such would have been OK. */
2110 tpd.level = TMPL_PARMS_DEPTH (current_template_parms);
2111 tpd.parms = alloca (sizeof (int) * ntparms);
2112 bzero ((PTR) tpd.parms, sizeof (int) * ntparms);
2113
2114 tpd.arg_uses_template_parms = alloca (sizeof (int) * nargs);
2115 bzero ((PTR) tpd.arg_uses_template_parms, sizeof (int) * nargs);
2116 for (i = 0; i < nargs; ++i)
2117 {
2118 tpd.current_arg = i;
2119 for_each_template_parm (TREE_VEC_ELT (inner_args, i),
2120 &mark_template_parm,
2121 &tpd);
2122 }
2123 for (i = 0; i < ntparms; ++i)
2124 if (tpd.parms[i] == 0)
2125 {
2126 /* One of the template parms was not used in the
2127 specialization. */
2128 if (!did_error_intro)
2129 {
2130 cp_error ("template parameters not used in partial specialization:");
2131 did_error_intro = 1;
2132 }
2133
2134 cp_error (" `%D'",
2135 TREE_VALUE (TREE_VEC_ELT (inner_parms, i)));
2136 }
2137
2138 /* [temp.class.spec]
2139
2140 The argument list of the specialization shall not be identical to
2141 the implicit argument list of the primary template. */
2142 if (comp_template_args
2143 (inner_args,
2144 INNERMOST_TEMPLATE_ARGS (CLASSTYPE_TI_ARGS (TREE_TYPE
2145 (maintmpl)))))
2146 cp_error ("partial specialization `%T' does not specialize any template arguments", type);
2147
2148 /* [temp.class.spec]
2149
2150 A partially specialized non-type argument expression shall not
2151 involve template parameters of the partial specialization except
2152 when the argument expression is a simple identifier.
2153
2154 The type of a template parameter corresponding to a specialized
2155 non-type argument shall not be dependent on a parameter of the
2156 specialization. */
2157 my_friendly_assert (nargs == DECL_NTPARMS (maintmpl), 0);
2158 tpd2.parms = 0;
2159 for (i = 0; i < nargs; ++i)
2160 {
2161 tree arg = TREE_VEC_ELT (inner_args, i);
2162 if (/* These first two lines are the `non-type' bit. */
2163 !TYPE_P (arg)
2164 && TREE_CODE (arg) != TEMPLATE_DECL
2165 /* This next line is the `argument expression is not just a
2166 simple identifier' condition and also the `specialized
2167 non-type argument' bit. */
2168 && TREE_CODE (arg) != TEMPLATE_PARM_INDEX)
2169 {
2170 if (tpd.arg_uses_template_parms[i])
2171 cp_error ("template argument `%E' involves template parameter(s)", arg);
2172 else
2173 {
2174 /* Look at the corresponding template parameter,
2175 marking which template parameters its type depends
2176 upon. */
2177 tree type =
2178 TREE_TYPE (TREE_VALUE (TREE_VEC_ELT (main_inner_parms,
2179 i)));
2180
2181 if (!tpd2.parms)
2182 {
2183 /* We haven't yet initialized TPD2. Do so now. */
2184 tpd2.arg_uses_template_parms
2185 = (int*) alloca (sizeof (int) * nargs);
2186 /* The number of parameters here is the number in the
2187 main template, which, as checked in the assertion
2188 above, is NARGS. */
2189 tpd2.parms = (int*) alloca (sizeof (int) * nargs);
2190 tpd2.level =
2191 TMPL_PARMS_DEPTH (DECL_TEMPLATE_PARMS (maintmpl));
2192 }
2193
2194 /* Mark the template parameters. But this time, we're
2195 looking for the template parameters of the main
2196 template, not in the specialization. */
2197 tpd2.current_arg = i;
2198 tpd2.arg_uses_template_parms[i] = 0;
2199 bzero ((PTR) tpd2.parms, sizeof (int) * nargs);
2200 for_each_template_parm (type,
2201 &mark_template_parm,
2202 &tpd2);
2203
2204 if (tpd2.arg_uses_template_parms [i])
2205 {
2206 /* The type depended on some template parameters.
2207 If they are fully specialized in the
2208 specialization, that's OK. */
2209 int j;
2210 for (j = 0; j < nargs; ++j)
2211 if (tpd2.parms[j] != 0
2212 && tpd.arg_uses_template_parms [j])
2213 {
2214 cp_error ("type `%T' of template argument `%E' depends on template parameter(s)",
2215 type,
2216 arg);
2217 break;
2218 }
2219 }
2220 }
2221 }
2222 }
2223
2224 if (retrieve_specialization (maintmpl, specargs))
2225 /* We've already got this specialization. */
2226 return decl;
2227
2228 DECL_TEMPLATE_SPECIALIZATIONS (maintmpl)
2229 = tree_cons (inner_args, inner_parms,
2230 DECL_TEMPLATE_SPECIALIZATIONS (maintmpl));
2231 TREE_TYPE (DECL_TEMPLATE_SPECIALIZATIONS (maintmpl)) = type;
2232 return decl;
2233 }
2234
2235 /* Check that a template declaration's use of default arguments is not
2236 invalid. Here, PARMS are the template parameters. IS_PRIMARY is
2237 non-zero if DECL is the thing declared by a primary template.
2238 IS_PARTIAL is non-zero if DECL is a partial specialization. */
2239
2240 static void
2241 check_default_tmpl_args (decl, parms, is_primary, is_partial)
2242 tree decl;
2243 tree parms;
2244 int is_primary;
2245 int is_partial;
2246 {
2247 const char *msg;
2248 int last_level_to_check;
2249 tree parm_level;
2250
2251 /* [temp.param]
2252
2253 A default template-argument shall not be specified in a
2254 function template declaration or a function template definition, nor
2255 in the template-parameter-list of the definition of a member of a
2256 class template. */
2257
2258 if (TREE_CODE (CP_DECL_CONTEXT (decl)) == FUNCTION_DECL)
2259 /* You can't have a function template declaration in a local
2260 scope, nor you can you define a member of a class template in a
2261 local scope. */
2262 return;
2263
2264 if (current_class_type
2265 && !TYPE_BEING_DEFINED (current_class_type)
2266 && DECL_LANG_SPECIFIC (decl)
2267 /* If this is either a friend defined in the scope of the class
2268 or a member function. */
2269 && ((DECL_CONTEXT (decl)
2270 && same_type_p (DECL_CONTEXT (decl), current_class_type))
2271 || (DECL_FRIEND_CONTEXT (decl)
2272 && same_type_p (DECL_FRIEND_CONTEXT (decl),
2273 current_class_type)))
2274 /* And, if it was a member function, it really was defined in
2275 the scope of the class. */
2276 && (!DECL_FUNCTION_MEMBER_P (decl) || DECL_DEFINED_IN_CLASS_P (decl)))
2277 /* We already checked these parameters when the template was
2278 declared, so there's no need to do it again now. This function
2279 was defined in class scope, but we're processing it's body now
2280 that the class is complete. */
2281 return;
2282
2283 /* [temp.param]
2284
2285 If a template-parameter has a default template-argument, all
2286 subsequent template-parameters shall have a default
2287 template-argument supplied. */
2288 for (parm_level = parms; parm_level; parm_level = TREE_CHAIN (parm_level))
2289 {
2290 tree inner_parms = TREE_VALUE (parm_level);
2291 int ntparms = TREE_VEC_LENGTH (inner_parms);
2292 int seen_def_arg_p = 0;
2293 int i;
2294
2295 for (i = 0; i < ntparms; ++i)
2296 {
2297 tree parm = TREE_VEC_ELT (inner_parms, i);
2298 if (TREE_PURPOSE (parm))
2299 seen_def_arg_p = 1;
2300 else if (seen_def_arg_p)
2301 {
2302 cp_error ("no default argument for `%D'", TREE_VALUE (parm));
2303 /* For better subsequent error-recovery, we indicate that
2304 there should have been a default argument. */
2305 TREE_PURPOSE (parm) = error_mark_node;
2306 }
2307 }
2308 }
2309
2310 if (TREE_CODE (decl) != TYPE_DECL || is_partial || !is_primary)
2311 /* For an ordinary class template, default template arguments are
2312 allowed at the innermost level, e.g.:
2313 template <class T = int>
2314 struct S {};
2315 but, in a partial specialization, they're not allowed even
2316 there, as we have in [temp.class.spec]:
2317
2318 The template parameter list of a specialization shall not
2319 contain default template argument values.
2320
2321 So, for a partial specialization, or for a function template,
2322 we look at all of them. */
2323 ;
2324 else
2325 /* But, for a primary class template that is not a partial
2326 specialization we look at all template parameters except the
2327 innermost ones. */
2328 parms = TREE_CHAIN (parms);
2329
2330 /* Figure out what error message to issue. */
2331 if (TREE_CODE (decl) == FUNCTION_DECL)
2332 msg = "default argument for template parameter in function template `%D'";
2333 else if (is_partial)
2334 msg = "default argument in partial specialization `%D'";
2335 else
2336 msg = "default argument for template parameter for class enclosing `%D'";
2337
2338 if (current_class_type && TYPE_BEING_DEFINED (current_class_type))
2339 /* If we're inside a class definition, there's no need to
2340 examine the parameters to the class itself. On the one
2341 hand, they will be checked when the class is defined, and,
2342 on the other, default arguments are legal in things like:
2343 template <class T = double>
2344 struct S { template <class U> void f(U); };
2345 Here the default argument for `S' has no bearing on the
2346 declaration of `f'. */
2347 last_level_to_check = template_class_depth (current_class_type) + 1;
2348 else
2349 /* Check everything. */
2350 last_level_to_check = 0;
2351
2352 for (parm_level = parms;
2353 parm_level && TMPL_PARMS_DEPTH (parm_level) >= last_level_to_check;
2354 parm_level = TREE_CHAIN (parm_level))
2355 {
2356 tree inner_parms = TREE_VALUE (parm_level);
2357 int i;
2358 int ntparms;
2359
2360 ntparms = TREE_VEC_LENGTH (inner_parms);
2361 for (i = 0; i < ntparms; ++i)
2362 if (TREE_PURPOSE (TREE_VEC_ELT (inner_parms, i)))
2363 {
2364 if (msg)
2365 {
2366 cp_error (msg, decl);
2367 msg = 0;
2368 }
2369
2370 /* Clear out the default argument so that we are not
2371 confused later. */
2372 TREE_PURPOSE (TREE_VEC_ELT (inner_parms, i)) = NULL_TREE;
2373 }
2374
2375 /* At this point, if we're still interested in issuing messages,
2376 they must apply to classes surrounding the object declared. */
2377 if (msg)
2378 msg = "default argument for template parameter for class enclosing `%D'";
2379 }
2380 }
2381
2382 /* Creates a TEMPLATE_DECL for the indicated DECL using the template
2383 parameters given by current_template_args, or reuses a
2384 previously existing one, if appropriate. Returns the DECL, or an
2385 equivalent one, if it is replaced via a call to duplicate_decls.
2386
2387 If IS_FRIEND is non-zero, DECL is a friend declaration. */
2388
2389 tree
2390 push_template_decl_real (decl, is_friend)
2391 tree decl;
2392 int is_friend;
2393 {
2394 tree tmpl;
2395 tree args;
2396 tree info;
2397 tree ctx;
2398 int primary;
2399 int is_partial;
2400 int new_template_p = 0;
2401
2402 /* See if this is a partial specialization. */
2403 is_partial = (DECL_IMPLICIT_TYPEDEF_P (decl)
2404 && TREE_CODE (TREE_TYPE (decl)) != ENUMERAL_TYPE
2405 && CLASSTYPE_TEMPLATE_SPECIALIZATION (TREE_TYPE (decl)));
2406
2407 is_friend |= (TREE_CODE (decl) == FUNCTION_DECL && DECL_FRIEND_P (decl));
2408
2409 if (is_friend)
2410 /* For a friend, we want the context of the friend function, not
2411 the type of which it is a friend. */
2412 ctx = DECL_CONTEXT (decl);
2413 else if (CP_DECL_CONTEXT (decl)
2414 && TREE_CODE (CP_DECL_CONTEXT (decl)) != NAMESPACE_DECL)
2415 /* In the case of a virtual function, we want the class in which
2416 it is defined. */
2417 ctx = CP_DECL_CONTEXT (decl);
2418 else
2419 /* Otherwise, if we're currently definining some class, the DECL
2420 is assumed to be a member of the class. */
2421 ctx = current_scope ();
2422
2423 if (ctx && TREE_CODE (ctx) == NAMESPACE_DECL)
2424 ctx = NULL_TREE;
2425
2426 if (!DECL_CONTEXT (decl))
2427 DECL_CONTEXT (decl) = FROB_CONTEXT (current_namespace);
2428
2429 /* See if this is a primary template. */
2430 primary = template_parm_scope_p ();
2431
2432 if (primary)
2433 {
2434 if (current_lang_name == lang_name_c)
2435 cp_error ("template with C linkage");
2436 else if (TREE_CODE (decl) == TYPE_DECL
2437 && ANON_AGGRNAME_P (DECL_NAME (decl)))
2438 cp_error ("template class without a name");
2439 else if ((DECL_IMPLICIT_TYPEDEF_P (decl)
2440 && CLASS_TYPE_P (TREE_TYPE (decl)))
2441 || (TREE_CODE (decl) == VAR_DECL && ctx && CLASS_TYPE_P (ctx))
2442 || TREE_CODE (decl) == FUNCTION_DECL)
2443 /* OK */;
2444 else
2445 cp_error ("template declaration of `%#D'", decl);
2446 }
2447
2448 /* Check to see that the rules regarding the use of default
2449 arguments are not being violated. */
2450 check_default_tmpl_args (decl, current_template_parms,
2451 primary, is_partial);
2452
2453 if (is_partial)
2454 return process_partial_specialization (decl);
2455
2456 args = current_template_args ();
2457
2458 if (!ctx
2459 || TREE_CODE (ctx) == FUNCTION_DECL
2460 || TYPE_BEING_DEFINED (ctx)
2461 || (is_friend && !DECL_TEMPLATE_INFO (decl)))
2462 {
2463 if (DECL_LANG_SPECIFIC (decl)
2464 && DECL_TEMPLATE_INFO (decl)
2465 && DECL_TI_TEMPLATE (decl))
2466 tmpl = DECL_TI_TEMPLATE (decl);
2467 /* If DECL is a TYPE_DECL for a class-template, then there won't
2468 be DECL_LANG_SPECIFIC. The information equivalent to
2469 DECL_TEMPLATE_INFO is found in TYPE_TEMPLATE_INFO instead. */
2470 else if (DECL_IMPLICIT_TYPEDEF_P (decl)
2471 && TYPE_TEMPLATE_INFO (TREE_TYPE (decl))
2472 && TYPE_TI_TEMPLATE (TREE_TYPE (decl)))
2473 {
2474 /* Since a template declaration already existed for this
2475 class-type, we must be redeclaring it here. Make sure
2476 that the redeclaration is legal. */
2477 redeclare_class_template (TREE_TYPE (decl),
2478 current_template_parms);
2479 /* We don't need to create a new TEMPLATE_DECL; just use the
2480 one we already had. */
2481 tmpl = TYPE_TI_TEMPLATE (TREE_TYPE (decl));
2482 }
2483 else
2484 {
2485 tmpl = build_template_decl (decl, current_template_parms);
2486 new_template_p = 1;
2487
2488 if (DECL_LANG_SPECIFIC (decl)
2489 && DECL_TEMPLATE_SPECIALIZATION (decl))
2490 {
2491 /* A specialization of a member template of a template
2492 class. */
2493 SET_DECL_TEMPLATE_SPECIALIZATION (tmpl);
2494 DECL_TEMPLATE_INFO (tmpl) = DECL_TEMPLATE_INFO (decl);
2495 DECL_TEMPLATE_INFO (decl) = NULL_TREE;
2496 }
2497 }
2498 }
2499 else
2500 {
2501 tree a, t, current, parms;
2502 int i;
2503
2504 if (TREE_CODE (decl) == TYPE_DECL)
2505 {
2506 if ((IS_AGGR_TYPE_CODE (TREE_CODE (TREE_TYPE (decl)))
2507 || TREE_CODE (TREE_TYPE (decl)) == ENUMERAL_TYPE)
2508 && TYPE_TEMPLATE_INFO (TREE_TYPE (decl))
2509 && TYPE_TI_TEMPLATE (TREE_TYPE (decl)))
2510 tmpl = TYPE_TI_TEMPLATE (TREE_TYPE (decl));
2511 else
2512 {
2513 cp_error ("`%D' does not declare a template type", decl);
2514 return decl;
2515 }
2516 }
2517 else if (! DECL_TEMPLATE_INFO (decl))
2518 {
2519 cp_error ("template definition of non-template `%#D'", decl);
2520 return decl;
2521 }
2522 else
2523 tmpl = DECL_TI_TEMPLATE (decl);
2524
2525 if (is_member_template (tmpl)
2526 && DECL_FUNCTION_TEMPLATE_P (tmpl)
2527 && DECL_TEMPLATE_INFO (decl) && DECL_TI_ARGS (decl)
2528 && DECL_TEMPLATE_SPECIALIZATION (decl))
2529 {
2530 tree new_tmpl;
2531
2532 /* The declaration is a specialization of a member
2533 template, declared outside the class. Therefore, the
2534 innermost template arguments will be NULL, so we
2535 replace them with the arguments determined by the
2536 earlier call to check_explicit_specialization. */
2537 args = DECL_TI_ARGS (decl);
2538
2539 new_tmpl
2540 = build_template_decl (decl, current_template_parms);
2541 DECL_TEMPLATE_RESULT (new_tmpl) = decl;
2542 TREE_TYPE (new_tmpl) = TREE_TYPE (decl);
2543 DECL_TI_TEMPLATE (decl) = new_tmpl;
2544 SET_DECL_TEMPLATE_SPECIALIZATION (new_tmpl);
2545 DECL_TEMPLATE_INFO (new_tmpl)
2546 = tree_cons (tmpl, args, NULL_TREE);
2547
2548 register_specialization (new_tmpl,
2549 most_general_template (tmpl),
2550 args);
2551 return decl;
2552 }
2553
2554 /* Make sure the template headers we got make sense. */
2555
2556 parms = DECL_TEMPLATE_PARMS (tmpl);
2557 i = TMPL_PARMS_DEPTH (parms);
2558 if (TMPL_ARGS_DEPTH (args) != i)
2559 {
2560 cp_error ("expected %d levels of template parms for `%#D', got %d",
2561 i, decl, TMPL_ARGS_DEPTH (args));
2562 }
2563 else
2564 for (current = decl; i > 0; --i, parms = TREE_CHAIN (parms))
2565 {
2566 a = TMPL_ARGS_LEVEL (args, i);
2567 t = INNERMOST_TEMPLATE_PARMS (parms);
2568
2569 if (TREE_VEC_LENGTH (t) != TREE_VEC_LENGTH (a))
2570 {
2571 if (current == decl)
2572 cp_error ("got %d template parameters for `%#D'",
2573 TREE_VEC_LENGTH (a), decl);
2574 else
2575 cp_error ("got %d template parameters for `%#T'",
2576 TREE_VEC_LENGTH (a), current);
2577 cp_error (" but %d required", TREE_VEC_LENGTH (t));
2578 }
2579
2580 /* Perhaps we should also check that the parms are used in the
2581 appropriate qualifying scopes in the declarator? */
2582
2583 if (current == decl)
2584 current = ctx;
2585 else
2586 current = TYPE_CONTEXT (current);
2587 }
2588 }
2589
2590 DECL_TEMPLATE_RESULT (tmpl) = decl;
2591 TREE_TYPE (tmpl) = TREE_TYPE (decl);
2592
2593 /* Push template declarations for global functions and types. Note
2594 that we do not try to push a global template friend declared in a
2595 template class; such a thing may well depend on the template
2596 parameters of the class. */
2597 if (new_template_p && !ctx
2598 && !(is_friend && template_class_depth (current_class_type) > 0))
2599 tmpl = pushdecl_namespace_level (tmpl);
2600
2601 if (primary)
2602 DECL_PRIMARY_TEMPLATE (tmpl) = tmpl;
2603
2604 info = tree_cons (tmpl, args, NULL_TREE);
2605
2606 if (DECL_IMPLICIT_TYPEDEF_P (decl))
2607 {
2608 SET_TYPE_TEMPLATE_INFO (TREE_TYPE (tmpl), info);
2609 if ((!ctx || TREE_CODE (ctx) != FUNCTION_DECL)
2610 && TREE_CODE (TREE_TYPE (decl)) != ENUMERAL_TYPE)
2611 DECL_NAME (decl) = classtype_mangled_name (TREE_TYPE (decl));
2612 }
2613 else if (DECL_LANG_SPECIFIC (decl))
2614 DECL_TEMPLATE_INFO (decl) = info;
2615
2616 return DECL_TEMPLATE_RESULT (tmpl);
2617 }
2618
2619 tree
2620 push_template_decl (decl)
2621 tree decl;
2622 {
2623 return push_template_decl_real (decl, 0);
2624 }
2625
2626 /* Called when a class template TYPE is redeclared with the indicated
2627 template PARMS, e.g.:
2628
2629 template <class T> struct S;
2630 template <class T> struct S {}; */
2631
2632 void
2633 redeclare_class_template (type, parms)
2634 tree type;
2635 tree parms;
2636 {
2637 tree tmpl;
2638 tree tmpl_parms;
2639 int i;
2640
2641 if (!TYPE_TEMPLATE_INFO (type))
2642 {
2643 cp_error ("`%T' is not a template type", type);
2644 return;
2645 }
2646
2647 tmpl = TYPE_TI_TEMPLATE (type);
2648 if (!PRIMARY_TEMPLATE_P (tmpl))
2649 /* The type is nested in some template class. Nothing to worry
2650 about here; there are no new template parameters for the nested
2651 type. */
2652 return;
2653
2654 parms = INNERMOST_TEMPLATE_PARMS (parms);
2655 tmpl_parms = DECL_INNERMOST_TEMPLATE_PARMS (tmpl);
2656
2657 if (TREE_VEC_LENGTH (parms) != TREE_VEC_LENGTH (tmpl_parms))
2658 {
2659 cp_error_at ("previous declaration `%D'", tmpl);
2660 cp_error ("used %d template parameter%s instead of %d",
2661 TREE_VEC_LENGTH (tmpl_parms),
2662 TREE_VEC_LENGTH (tmpl_parms) == 1 ? "" : "s",
2663 TREE_VEC_LENGTH (parms));
2664 return;
2665 }
2666
2667 for (i = 0; i < TREE_VEC_LENGTH (tmpl_parms); ++i)
2668 {
2669 tree tmpl_parm = TREE_VALUE (TREE_VEC_ELT (tmpl_parms, i));
2670 tree parm = TREE_VALUE (TREE_VEC_ELT (parms, i));
2671 tree tmpl_default = TREE_PURPOSE (TREE_VEC_ELT (tmpl_parms, i));
2672 tree parm_default = TREE_PURPOSE (TREE_VEC_ELT (parms, i));
2673
2674 if (TREE_CODE (tmpl_parm) != TREE_CODE (parm))
2675 {
2676 cp_error_at ("template parameter `%#D'", tmpl_parm);
2677 cp_error ("redeclared here as `%#D'", parm);
2678 return;
2679 }
2680
2681 if (tmpl_default != NULL_TREE && parm_default != NULL_TREE)
2682 {
2683 /* We have in [temp.param]:
2684
2685 A template-parameter may not be given default arguments
2686 by two different declarations in the same scope. */
2687 cp_error ("redefinition of default argument for `%#D'", parm);
2688 cp_error_at (" original definition appeared here", tmpl_parm);
2689 return;
2690 }
2691
2692 if (parm_default != NULL_TREE)
2693 /* Update the previous template parameters (which are the ones
2694 that will really count) with the new default value. */
2695 TREE_PURPOSE (TREE_VEC_ELT (tmpl_parms, i)) = parm_default;
2696 else if (tmpl_default != NULL_TREE)
2697 /* Update the new parameters, too; they'll be used as the
2698 parameters for any members. */
2699 TREE_PURPOSE (TREE_VEC_ELT (parms, i)) = tmpl_default;
2700 }
2701 }
2702
2703 /* Attempt to convert the non-type template parameter EXPR to the
2704 indicated TYPE. If the conversion is successful, return the
2705 converted value. If the conversion is unsuccesful, return
2706 NULL_TREE if we issued an error message, or error_mark_node if we
2707 did not. We issue error messages for out-and-out bad template
2708 parameters, but not simply because the conversion failed, since we
2709 might be just trying to do argument deduction. By the time this
2710 function is called, neither TYPE nor EXPR may make use of template
2711 parameters. */
2712
2713 static tree
2714 convert_nontype_argument (type, expr)
2715 tree type;
2716 tree expr;
2717 {
2718 tree expr_type = TREE_TYPE (expr);
2719
2720 /* A template-argument for a non-type, non-template
2721 template-parameter shall be one of:
2722
2723 --an integral constant-expression of integral or enumeration
2724 type; or
2725
2726 --the name of a non-type template-parameter; or
2727
2728 --the name of an object or function with external linkage,
2729 including function templates and function template-ids but
2730 excluding non-static class members, expressed as id-expression;
2731 or
2732
2733 --the address of an object or function with external linkage,
2734 including function templates and function template-ids but
2735 excluding non-static class members, expressed as & id-expression
2736 where the & is optional if the name refers to a function or
2737 array; or
2738
2739 --a pointer to member expressed as described in _expr.unary.op_. */
2740
2741 /* An integral constant-expression can include const variables or
2742 enumerators. Simplify things by folding them to their values,
2743 unless we're about to bind the declaration to a reference
2744 parameter. */
2745 if (INTEGRAL_TYPE_P (expr_type)
2746 && TREE_CODE (type) != REFERENCE_TYPE)
2747 expr = decl_constant_value (expr);
2748
2749 if (is_overloaded_fn (expr))
2750 /* OK for now. We'll check that it has external linkage later.
2751 Check this first since if expr_type is the unknown_type_node
2752 we would otherwise complain below. */
2753 ;
2754 else if (TYPE_PTRMEM_P (expr_type)
2755 || TYPE_PTRMEMFUNC_P (expr_type))
2756 {
2757 if (TREE_CODE (expr) != PTRMEM_CST)
2758 goto bad_argument;
2759 }
2760 else if (TYPE_PTR_P (expr_type)
2761 || TYPE_PTRMEM_P (expr_type)
2762 || TREE_CODE (expr_type) == ARRAY_TYPE
2763 || TREE_CODE (type) == REFERENCE_TYPE
2764 /* If expr is the address of an overloaded function, we
2765 will get the unknown_type_node at this point. */
2766 || expr_type == unknown_type_node)
2767 {
2768 tree referent;
2769 tree e = expr;
2770 STRIP_NOPS (e);
2771
2772 if (TREE_CODE (expr_type) == ARRAY_TYPE
2773 || (TREE_CODE (type) == REFERENCE_TYPE
2774 && TREE_CODE (e) != ADDR_EXPR))
2775 referent = e;
2776 else
2777 {
2778 if (TREE_CODE (e) != ADDR_EXPR)
2779 {
2780 bad_argument:
2781 cp_error ("`%E' is not a valid template argument", expr);
2782 if (TYPE_PTR_P (expr_type))
2783 {
2784 if (TREE_CODE (TREE_TYPE (expr_type)) == FUNCTION_TYPE)
2785 cp_error ("it must be the address of a function with external linkage");
2786 else
2787 cp_error ("it must be the address of an object with external linkage");
2788 }
2789 else if (TYPE_PTRMEM_P (expr_type)
2790 || TYPE_PTRMEMFUNC_P (expr_type))
2791 cp_error ("it must be a pointer-to-member of the form `&X::Y'");
2792
2793 return NULL_TREE;
2794 }
2795
2796 referent = TREE_OPERAND (e, 0);
2797 STRIP_NOPS (referent);
2798 }
2799
2800 if (TREE_CODE (referent) == STRING_CST)
2801 {
2802 cp_error ("string literal %E is not a valid template argument because it is the address of an object with static linkage",
2803 referent);
2804 return NULL_TREE;
2805 }
2806
2807 if (is_overloaded_fn (referent))
2808 /* We'll check that it has external linkage later. */
2809 ;
2810 else if (TREE_CODE (referent) != VAR_DECL)
2811 goto bad_argument;
2812 else if (!TREE_PUBLIC (referent))
2813 {
2814 cp_error ("address of non-extern `%E' cannot be used as template argument", referent);
2815 return error_mark_node;
2816 }
2817 }
2818 else if (INTEGRAL_TYPE_P (expr_type)
2819 || TYPE_PTRMEM_P (expr_type)
2820 || TYPE_PTRMEMFUNC_P (expr_type)
2821 /* The next two are g++ extensions. */
2822 || TREE_CODE (expr_type) == REAL_TYPE
2823 || TREE_CODE (expr_type) == COMPLEX_TYPE)
2824 {
2825 if (! TREE_CONSTANT (expr))
2826 {
2827 non_constant:
2828 cp_error ("non-constant `%E' cannot be used as template argument",
2829 expr);
2830 return NULL_TREE;
2831 }
2832 }
2833 else
2834 {
2835 cp_error ("object `%E' cannot be used as template argument", expr);
2836 return NULL_TREE;
2837 }
2838
2839 switch (TREE_CODE (type))
2840 {
2841 case INTEGER_TYPE:
2842 case BOOLEAN_TYPE:
2843 case ENUMERAL_TYPE:
2844 /* For a non-type template-parameter of integral or enumeration
2845 type, integral promotions (_conv.prom_) and integral
2846 conversions (_conv.integral_) are applied. */
2847 if (!INTEGRAL_TYPE_P (expr_type))
2848 return error_mark_node;
2849
2850 /* It's safe to call digest_init in this case; we know we're
2851 just converting one integral constant expression to another. */
2852 expr = digest_init (type, expr, (tree*) 0);
2853
2854 if (TREE_CODE (expr) != INTEGER_CST)
2855 /* Curiously, some TREE_CONSTANT integral expressions do not
2856 simplify to integer constants. For example, `3 % 0',
2857 remains a TRUNC_MOD_EXPR. */
2858 goto non_constant;
2859
2860 return expr;
2861
2862 case REAL_TYPE:
2863 case COMPLEX_TYPE:
2864 /* These are g++ extensions. */
2865 if (TREE_CODE (expr_type) != TREE_CODE (type))
2866 return error_mark_node;
2867
2868 expr = digest_init (type, expr, (tree*) 0);
2869
2870 if (TREE_CODE (expr) != REAL_CST)
2871 goto non_constant;
2872
2873 return expr;
2874
2875 case POINTER_TYPE:
2876 {
2877 tree type_pointed_to = TREE_TYPE (type);
2878
2879 if (TYPE_PTRMEM_P (type))
2880 {
2881 tree e;
2882
2883 /* For a non-type template-parameter of type pointer to data
2884 member, qualification conversions (_conv.qual_) are
2885 applied. */
2886 e = perform_qualification_conversions (type, expr);
2887 if (TREE_CODE (e) == NOP_EXPR)
2888 /* The call to perform_qualification_conversions will
2889 insert a NOP_EXPR over EXPR to do express conversion,
2890 if necessary. But, that will confuse us if we use
2891 this (converted) template parameter to instantiate
2892 another template; then the thing will not look like a
2893 valid template argument. So, just make a new
2894 constant, of the appropriate type. */
2895 e = make_ptrmem_cst (type, PTRMEM_CST_MEMBER (expr));
2896 return e;
2897 }
2898 else if (TREE_CODE (type_pointed_to) == FUNCTION_TYPE)
2899 {
2900 /* For a non-type template-parameter of type pointer to
2901 function, only the function-to-pointer conversion
2902 (_conv.func_) is applied. If the template-argument
2903 represents a set of overloaded functions (or a pointer to
2904 such), the matching function is selected from the set
2905 (_over.over_). */
2906 tree fns;
2907 tree fn;
2908
2909 if (TREE_CODE (expr) == ADDR_EXPR)
2910 fns = TREE_OPERAND (expr, 0);
2911 else
2912 fns = expr;
2913
2914 fn = instantiate_type (type_pointed_to, fns, 0);
2915
2916 if (fn == error_mark_node)
2917 return error_mark_node;
2918
2919 if (!TREE_PUBLIC (fn))
2920 {
2921 if (really_overloaded_fn (fns))
2922 return error_mark_node;
2923 else
2924 goto bad_argument;
2925 }
2926
2927 expr = build_unary_op (ADDR_EXPR, fn, 0);
2928
2929 my_friendly_assert (same_type_p (type, TREE_TYPE (expr)),
2930 0);
2931 return expr;
2932 }
2933 else
2934 {
2935 /* For a non-type template-parameter of type pointer to
2936 object, qualification conversions (_conv.qual_) and the
2937 array-to-pointer conversion (_conv.array_) are applied.
2938 [Note: In particular, neither the null pointer conversion
2939 (_conv.ptr_) nor the derived-to-base conversion
2940 (_conv.ptr_) are applied. Although 0 is a valid
2941 template-argument for a non-type template-parameter of
2942 integral type, it is not a valid template-argument for a
2943 non-type template-parameter of pointer type.]
2944
2945 The call to decay_conversion performs the
2946 array-to-pointer conversion, if appropriate. */
2947 expr = decay_conversion (expr);
2948
2949 if (expr == error_mark_node)
2950 return error_mark_node;
2951 else
2952 return perform_qualification_conversions (type, expr);
2953 }
2954 }
2955 break;
2956
2957 case REFERENCE_TYPE:
2958 {
2959 tree type_referred_to = TREE_TYPE (type);
2960
2961 /* If this expression already has reference type, get the
2962 underling object. */
2963 if (TREE_CODE (expr_type) == REFERENCE_TYPE)
2964 {
2965 my_friendly_assert (TREE_CODE (expr) == ADDR_EXPR, 20000604);
2966 expr = TREE_OPERAND (expr, 0);
2967 expr_type = TREE_TYPE (expr);
2968 }
2969
2970 if (TREE_CODE (type_referred_to) == FUNCTION_TYPE)
2971 {
2972 /* For a non-type template-parameter of type reference to
2973 function, no conversions apply. If the
2974 template-argument represents a set of overloaded
2975 functions, the matching function is selected from the
2976 set (_over.over_). */
2977 tree fn;
2978
2979 fn = instantiate_type (type_referred_to, expr, 0);
2980
2981 if (fn == error_mark_node)
2982 return error_mark_node;
2983
2984 if (!TREE_PUBLIC (fn))
2985 {
2986 if (really_overloaded_fn (expr))
2987 /* Don't issue an error here; we might get a different
2988 function if the overloading had worked out
2989 differently. */
2990 return error_mark_node;
2991 else
2992 goto bad_argument;
2993 }
2994
2995 my_friendly_assert (same_type_p (type_referred_to,
2996 TREE_TYPE (fn)),
2997 0);
2998
2999 expr = fn;
3000 }
3001 else
3002 {
3003 /* For a non-type template-parameter of type reference to
3004 object, no conversions apply. The type referred to by the
3005 reference may be more cv-qualified than the (otherwise
3006 identical) type of the template-argument. The
3007 template-parameter is bound directly to the
3008 template-argument, which must be an lvalue. */
3009 if (!same_type_p (TYPE_MAIN_VARIANT (expr_type),
3010 TYPE_MAIN_VARIANT (type_referred_to))
3011 || !at_least_as_qualified_p (type_referred_to,
3012 expr_type)
3013 || !real_lvalue_p (expr))
3014 return error_mark_node;
3015 }
3016
3017 mark_addressable (expr);
3018 return build1 (ADDR_EXPR, type, expr);
3019 }
3020 break;
3021
3022 case RECORD_TYPE:
3023 {
3024 if (!TYPE_PTRMEMFUNC_P (type))
3025 /* This handles templates like
3026 template<class T, T t> void f();
3027 when T is substituted with any class. The second template
3028 parameter becomes invalid and the template candidate is
3029 rejected. */
3030 return error_mark_node;
3031
3032 /* For a non-type template-parameter of type pointer to member
3033 function, no conversions apply. If the template-argument
3034 represents a set of overloaded member functions, the
3035 matching member function is selected from the set
3036 (_over.over_). */
3037
3038 if (!TYPE_PTRMEMFUNC_P (expr_type) &&
3039 expr_type != unknown_type_node)
3040 return error_mark_node;
3041
3042 if (TREE_CODE (expr) == PTRMEM_CST)
3043 {
3044 /* A ptr-to-member constant. */
3045 if (!same_type_p (type, expr_type))
3046 return error_mark_node;
3047 else
3048 return expr;
3049 }
3050
3051 if (TREE_CODE (expr) != ADDR_EXPR)
3052 return error_mark_node;
3053
3054 expr = instantiate_type (type, expr, 0);
3055
3056 if (expr == error_mark_node)
3057 return error_mark_node;
3058
3059 my_friendly_assert (same_type_p (type, TREE_TYPE (expr)),
3060 0);
3061 return expr;
3062 }
3063 break;
3064
3065 default:
3066 /* All non-type parameters must have one of these types. */
3067 my_friendly_abort (0);
3068 break;
3069 }
3070
3071 return error_mark_node;
3072 }
3073
3074 /* Return 1 if PARM_PARMS and ARG_PARMS matches using rule for
3075 template template parameters. Both PARM_PARMS and ARG_PARMS are
3076 vectors of TREE_LIST nodes containing TYPE_DECL, TEMPLATE_DECL
3077 or PARM_DECL.
3078
3079 ARG_PARMS may contain more parameters than PARM_PARMS. If this is
3080 the case, then extra parameters must have default arguments.
3081
3082 Consider the example:
3083 template <class T, class Allocator = allocator> class vector;
3084 template<template <class U> class TT> class C;
3085
3086 C<vector> is a valid instantiation. PARM_PARMS for the above code
3087 contains a TYPE_DECL (for U), ARG_PARMS contains two TYPE_DECLs (for
3088 T and Allocator) and OUTER_ARGS contains the argument that is used to
3089 substitute the TT parameter. */
3090
3091 static int
3092 coerce_template_template_parms (parm_parms, arg_parms, complain,
3093 in_decl, outer_args)
3094 tree parm_parms, arg_parms;
3095 int complain;
3096 tree in_decl, outer_args;
3097 {
3098 int nparms, nargs, i;
3099 tree parm, arg;
3100
3101 my_friendly_assert (TREE_CODE (parm_parms) == TREE_VEC, 0);
3102 my_friendly_assert (TREE_CODE (arg_parms) == TREE_VEC, 0);
3103
3104 nparms = TREE_VEC_LENGTH (parm_parms);
3105 nargs = TREE_VEC_LENGTH (arg_parms);
3106
3107 /* The rule here is opposite of coerce_template_parms. */
3108 if (nargs < nparms
3109 || (nargs > nparms
3110 && TREE_PURPOSE (TREE_VEC_ELT (arg_parms, nparms)) == NULL_TREE))
3111 return 0;
3112
3113 for (i = 0; i < nparms; ++i)
3114 {
3115 parm = TREE_VALUE (TREE_VEC_ELT (parm_parms, i));
3116 arg = TREE_VALUE (TREE_VEC_ELT (arg_parms, i));
3117
3118 if (arg == NULL_TREE || arg == error_mark_node
3119 || parm == NULL_TREE || parm == error_mark_node)
3120 return 0;
3121
3122 if (TREE_CODE (arg) != TREE_CODE (parm))
3123 return 0;
3124
3125 switch (TREE_CODE (parm))
3126 {
3127 case TYPE_DECL:
3128 break;
3129
3130 case TEMPLATE_DECL:
3131 /* We encounter instantiations of templates like
3132 template <template <template <class> class> class TT>
3133 class C; */
3134 {
3135 tree parmparm = DECL_INNERMOST_TEMPLATE_PARMS (parm);
3136 tree argparm = DECL_INNERMOST_TEMPLATE_PARMS (arg);
3137
3138 if (!coerce_template_template_parms (parmparm, argparm,
3139 complain, in_decl,
3140 outer_args))
3141 return 0;
3142 }
3143 break;
3144
3145 case PARM_DECL:
3146 /* The tsubst call is used to handle cases such as
3147 template <class T, template <T> class TT> class D;
3148 i.e. the parameter list of TT depends on earlier parameters. */
3149 if (!same_type_p (tsubst (TREE_TYPE (parm), outer_args,
3150 complain, in_decl),
3151 TREE_TYPE (arg)))
3152 return 0;
3153 break;
3154
3155 default:
3156 my_friendly_abort (0);
3157 }
3158 }
3159 return 1;
3160 }
3161
3162 /* Convert the indicated template ARG as necessary to match the
3163 indicated template PARM. Returns the converted ARG, or
3164 error_mark_node if the conversion was unsuccessful. Error messages
3165 are issued if COMPLAIN is non-zero. This conversion is for the Ith
3166 parameter in the parameter list. ARGS is the full set of template
3167 arguments deduced so far. */
3168
3169 static tree
3170 convert_template_argument (parm, arg, args, complain, i, in_decl)
3171 tree parm;
3172 tree arg;
3173 tree args;
3174 int complain;
3175 int i;
3176 tree in_decl;
3177 {
3178 tree val;
3179 tree inner_args;
3180 int is_type, requires_type, is_tmpl_type, requires_tmpl_type;
3181
3182 inner_args = INNERMOST_TEMPLATE_ARGS (args);
3183
3184 if (TREE_CODE (arg) == TREE_LIST
3185 && TREE_TYPE (arg) != NULL_TREE
3186 && TREE_CODE (TREE_TYPE (arg)) == OFFSET_TYPE)
3187 {
3188 /* The template argument was the name of some
3189 member function. That's usually
3190 illegal, but static members are OK. In any
3191 case, grab the underlying fields/functions
3192 and issue an error later if required. */
3193 arg = TREE_VALUE (arg);
3194 TREE_TYPE (arg) = unknown_type_node;
3195 }
3196
3197 requires_tmpl_type = TREE_CODE (parm) == TEMPLATE_DECL;
3198 requires_type = (TREE_CODE (parm) == TYPE_DECL
3199 || requires_tmpl_type);
3200
3201 /* Check if it is a class template. If REQUIRES_TMPL_TYPE is true,
3202 we also accept implicitly created TYPE_DECL as a valid argument.
3203 This is necessary to handle the case where we pass a template name
3204 to a template template parameter in a scope where we've derived from
3205 in instantiation of that template, so the template name refers to that
3206 instantiation. We really ought to handle this better. */
3207 is_tmpl_type
3208 = ((TREE_CODE (arg) == TEMPLATE_DECL
3209 && TREE_CODE (DECL_TEMPLATE_RESULT (arg)) == TYPE_DECL)
3210 || (TREE_CODE (arg) == TEMPLATE_TEMPLATE_PARM
3211 && !TEMPLATE_TEMPLATE_PARM_TEMPLATE_INFO (arg))
3212 || (TREE_CODE (arg) == RECORD_TYPE
3213 && CLASSTYPE_TEMPLATE_INFO (arg)
3214 && TREE_CODE (TYPE_NAME (arg)) == TYPE_DECL
3215 && DECL_ARTIFICIAL (TYPE_NAME (arg))
3216 && requires_tmpl_type
3217 && is_base_of_enclosing_class (arg, current_class_type)));
3218 if (is_tmpl_type && TREE_CODE (arg) == TEMPLATE_TEMPLATE_PARM)
3219 arg = TYPE_STUB_DECL (arg);
3220 else if (is_tmpl_type && TREE_CODE (arg) == RECORD_TYPE)
3221 arg = CLASSTYPE_TI_TEMPLATE (arg);
3222
3223 is_type = TYPE_P (arg) || is_tmpl_type;
3224
3225 if (requires_type && ! is_type && TREE_CODE (arg) == SCOPE_REF
3226 && TREE_CODE (TREE_OPERAND (arg, 0)) == TEMPLATE_TYPE_PARM)
3227 {
3228 cp_pedwarn ("to refer to a type member of a template parameter, use `typename %E'", arg);
3229
3230 arg = make_typename_type (TREE_OPERAND (arg, 0),
3231 TREE_OPERAND (arg, 1),
3232 complain);
3233 is_type = 1;
3234 }
3235 if (is_type != requires_type)
3236 {
3237 if (in_decl)
3238 {
3239 if (complain)
3240 {
3241 cp_error ("type/value mismatch at argument %d in template parameter list for `%D'",
3242 i + 1, in_decl);
3243 if (is_type)
3244 cp_error (" expected a constant of type `%T', got `%T'",
3245 TREE_TYPE (parm),
3246 (is_tmpl_type ? DECL_NAME (arg) : arg));
3247 else
3248 cp_error (" expected a type, got `%E'", arg);
3249 }
3250 }
3251 return error_mark_node;
3252 }
3253 if (is_tmpl_type ^ requires_tmpl_type)
3254 {
3255 if (in_decl && complain)
3256 {
3257 cp_error ("type/value mismatch at argument %d in template parameter list for `%D'",
3258 i + 1, in_decl);
3259 if (is_tmpl_type)
3260 cp_error (" expected a type, got `%T'", DECL_NAME (arg));
3261 else
3262 cp_error (" expected a class template, got `%T'", arg);
3263 }
3264 return error_mark_node;
3265 }
3266
3267 if (is_type)
3268 {
3269 if (requires_tmpl_type)
3270 {
3271 tree parmparm = DECL_INNERMOST_TEMPLATE_PARMS (parm);
3272 tree argparm = DECL_INNERMOST_TEMPLATE_PARMS (arg);
3273
3274 if (coerce_template_template_parms (parmparm, argparm, complain,
3275 in_decl, inner_args))
3276 {
3277 val = arg;
3278
3279 /* TEMPLATE_TEMPLATE_PARM node is preferred over
3280 TEMPLATE_DECL. */
3281 if (val != error_mark_node
3282 && DECL_TEMPLATE_TEMPLATE_PARM_P (val))
3283 val = TREE_TYPE (val);
3284 }
3285 else
3286 {
3287 if (in_decl && complain)
3288 {
3289 cp_error ("type/value mismatch at argument %d in template parameter list for `%D'",
3290 i + 1, in_decl);
3291 cp_error (" expected a template of type `%D', got `%D'", parm, arg);
3292 }
3293
3294 val = error_mark_node;
3295 }
3296 }
3297 else
3298 {
3299 val = groktypename (arg);
3300 if (! processing_template_decl)
3301 {
3302 /* [basic.link]: A name with no linkage (notably, the
3303 name of a class or enumeration declared in a local
3304 scope) shall not be used to declare an entity with
3305 linkage. This implies that names with no linkage
3306 cannot be used as template arguments. */
3307 tree t = no_linkage_check (val);
3308 if (t)
3309 {
3310 if (ANON_AGGRNAME_P (TYPE_IDENTIFIER (t)))
3311 cp_pedwarn
3312 ("template-argument `%T' uses anonymous type", val);
3313 else
3314 cp_error
3315 ("template-argument `%T' uses local type `%T'",
3316 val, t);
3317 return error_mark_node;
3318 }
3319 }
3320 }
3321 }
3322 else
3323 {
3324 tree t = tsubst (TREE_TYPE (parm), args, complain, in_decl);
3325
3326 if (processing_template_decl)
3327 arg = maybe_fold_nontype_arg (arg);
3328
3329 if (!uses_template_parms (arg) && !uses_template_parms (t))
3330 /* We used to call digest_init here. However, digest_init
3331 will report errors, which we don't want when complain
3332 is zero. More importantly, digest_init will try too
3333 hard to convert things: for example, `0' should not be
3334 converted to pointer type at this point according to
3335 the standard. Accepting this is not merely an
3336 extension, since deciding whether or not these
3337 conversions can occur is part of determining which
3338 function template to call, or whether a given epxlicit
3339 argument specification is legal. */
3340 val = convert_nontype_argument (t, arg);
3341 else
3342 val = arg;
3343
3344 if (val == NULL_TREE)
3345 val = error_mark_node;
3346 else if (val == error_mark_node && complain)
3347 cp_error ("could not convert template argument `%E' to `%T'",
3348 arg, t);
3349 }
3350
3351 return val;
3352 }
3353
3354 /* Convert all template arguments to their appropriate types, and
3355 return a vector containing the innermost resulting template
3356 arguments. If any error occurs, return error_mark_node, and, if
3357 COMPLAIN is non-zero, issue an error message. Some error messages
3358 are issued even if COMPLAIN is zero; for instance, if a template
3359 argument is composed from a local class.
3360
3361 If REQUIRE_ALL_ARGUMENTS is non-zero, all arguments must be
3362 provided in ARGLIST, or else trailing parameters must have default
3363 values. If REQUIRE_ALL_ARGUMENTS is zero, we will attempt argument
3364 deduction for any unspecified trailing arguments. */
3365
3366 static tree
3367 coerce_template_parms (parms, args, in_decl,
3368 complain,
3369 require_all_arguments)
3370 tree parms, args;
3371 tree in_decl;
3372 int complain;
3373 int require_all_arguments;
3374 {
3375 int nparms, nargs, i, lost = 0;
3376 tree inner_args;
3377 tree new_args;
3378 tree new_inner_args;
3379
3380 inner_args = INNERMOST_TEMPLATE_ARGS (args);
3381 nargs = NUM_TMPL_ARGS (inner_args);
3382 nparms = TREE_VEC_LENGTH (parms);
3383
3384 if (nargs > nparms
3385 || (nargs < nparms
3386 && require_all_arguments
3387 && TREE_PURPOSE (TREE_VEC_ELT (parms, nargs)) == NULL_TREE))
3388 {
3389 if (complain)
3390 {
3391 cp_error ("wrong number of template arguments (%d, should be %d)",
3392 nargs, nparms);
3393
3394 if (in_decl)
3395 cp_error_at ("provided for `%D'", in_decl);
3396 }
3397
3398 return error_mark_node;
3399 }
3400
3401 new_inner_args = make_tree_vec (nparms);
3402 new_args = add_outermost_template_args (args, new_inner_args);
3403 for (i = 0; i < nparms; i++)
3404 {
3405 tree arg;
3406 tree parm;
3407
3408 /* Get the Ith template parameter. */
3409 parm = TREE_VEC_ELT (parms, i);
3410
3411 /* Calculate the Ith argument. */
3412 if (inner_args && TREE_CODE (inner_args) == TREE_LIST)
3413 {
3414 arg = TREE_VALUE (inner_args);
3415 inner_args = TREE_CHAIN (inner_args);
3416 }
3417 else if (i < nargs)
3418 arg = TREE_VEC_ELT (inner_args, i);
3419 /* If no template argument was supplied, look for a default
3420 value. */
3421 else if (TREE_PURPOSE (parm) == NULL_TREE)
3422 {
3423 /* There was no default value. */
3424 my_friendly_assert (!require_all_arguments, 0);
3425 break;
3426 }
3427 else if (TREE_CODE (TREE_VALUE (parm)) == TYPE_DECL)
3428 arg = tsubst (TREE_PURPOSE (parm), new_args, complain, in_decl);
3429 else
3430 arg = tsubst_expr (TREE_PURPOSE (parm), new_args, complain,
3431 in_decl);
3432
3433 /* Now, convert the Ith argument, as necessary. */
3434 if (arg == NULL_TREE)
3435 /* We're out of arguments. */
3436 {
3437 my_friendly_assert (!require_all_arguments, 0);
3438 break;
3439 }
3440 else if (arg == error_mark_node)
3441 {
3442 cp_error ("template argument %d is invalid", i + 1);
3443 arg = error_mark_node;
3444 }
3445 else
3446 arg = convert_template_argument (TREE_VALUE (parm),
3447 arg, new_args, complain, i,
3448 in_decl);
3449
3450 if (arg == error_mark_node)
3451 lost++;
3452 TREE_VEC_ELT (new_inner_args, i) = arg;
3453 }
3454
3455 if (lost)
3456 return error_mark_node;
3457
3458 return new_inner_args;
3459 }
3460
3461 /* Returns 1 if template args OT and NT are equivalent. */
3462
3463 static int
3464 template_args_equal (ot, nt)
3465 tree ot, nt;
3466 {
3467 if (nt == ot)
3468 return 1;
3469 if (TREE_CODE (nt) != TREE_CODE (ot))
3470 return 0;
3471 if (TREE_CODE (nt) == TREE_VEC)
3472 /* For member templates */
3473 return comp_template_args (ot, nt);
3474 else if (TYPE_P (ot))
3475 return same_type_p (ot, nt);
3476 else
3477 return (cp_tree_equal (ot, nt) > 0);
3478 }
3479
3480 /* Returns 1 iff the OLDARGS and NEWARGS are in fact identical sets
3481 of template arguments. Returns 0 otherwise. */
3482
3483 int
3484 comp_template_args (oldargs, newargs)
3485 tree oldargs, newargs;
3486 {
3487 int i;
3488
3489 if (TREE_VEC_LENGTH (oldargs) != TREE_VEC_LENGTH (newargs))
3490 return 0;
3491
3492 for (i = 0; i < TREE_VEC_LENGTH (oldargs); ++i)
3493 {
3494 tree nt = TREE_VEC_ELT (newargs, i);
3495 tree ot = TREE_VEC_ELT (oldargs, i);
3496
3497 if (! template_args_equal (ot, nt))
3498 return 0;
3499 }
3500 return 1;
3501 }
3502
3503 /* Given class template name and parameter list, produce a user-friendly name
3504 for the instantiation. */
3505
3506 static char *
3507 mangle_class_name_for_template (name, parms, arglist)
3508 char *name;
3509 tree parms, arglist;
3510 {
3511 static struct obstack scratch_obstack;
3512 static char *scratch_firstobj;
3513 int i, nparms;
3514
3515 if (!scratch_firstobj)
3516 gcc_obstack_init (&scratch_obstack);
3517 else
3518 obstack_free (&scratch_obstack, scratch_firstobj);
3519 scratch_firstobj = obstack_alloc (&scratch_obstack, 1);
3520
3521 #define ccat(c) obstack_1grow (&scratch_obstack, (c));
3522 #define cat(s) obstack_grow (&scratch_obstack, (s), strlen (s))
3523
3524 cat (name);
3525 ccat ('<');
3526 nparms = TREE_VEC_LENGTH (parms);
3527 arglist = INNERMOST_TEMPLATE_ARGS (arglist);
3528 my_friendly_assert (nparms == TREE_VEC_LENGTH (arglist), 268);
3529 for (i = 0; i < nparms; i++)
3530 {
3531 tree parm = TREE_VALUE (TREE_VEC_ELT (parms, i));
3532 tree arg = TREE_VEC_ELT (arglist, i);
3533
3534 if (i)
3535 ccat (',');
3536
3537 if (TREE_CODE (parm) == TYPE_DECL)
3538 {
3539 cat (type_as_string (arg, TS_CHASE_TYPEDEFS));
3540 continue;
3541 }
3542 else if (TREE_CODE (parm) == TEMPLATE_DECL)
3543 {
3544 if (TREE_CODE (arg) == TEMPLATE_DECL)
3545 {
3546 /* Already substituted with real template. Just output
3547 the template name here */
3548 tree context = DECL_CONTEXT (arg);
3549 if (context)
3550 {
3551 /* The template may be defined in a namespace, or
3552 may be a member template. */
3553 my_friendly_assert (TREE_CODE (context) == NAMESPACE_DECL
3554 || CLASS_TYPE_P (context),
3555 980422);
3556 cat(decl_as_string (DECL_CONTEXT (arg), 0));
3557 cat("::");
3558 }
3559 cat (IDENTIFIER_POINTER (DECL_NAME (arg)));
3560 }
3561 else
3562 /* Output the parameter declaration */
3563 cat (type_as_string (arg, TS_CHASE_TYPEDEFS));
3564 continue;
3565 }
3566 else
3567 my_friendly_assert (TREE_CODE (parm) == PARM_DECL, 269);
3568
3569 if (TREE_CODE (arg) == TREE_LIST)
3570 {
3571 /* New list cell was built because old chain link was in
3572 use. */
3573 my_friendly_assert (TREE_PURPOSE (arg) == NULL_TREE, 270);
3574 arg = TREE_VALUE (arg);
3575 }
3576 /* No need to check arglist against parmlist here; we did that
3577 in coerce_template_parms, called from lookup_template_class. */
3578 cat (expr_as_string (arg, 0));
3579 }
3580 {
3581 char *bufp = obstack_next_free (&scratch_obstack);
3582 int offset = 0;
3583 while (bufp[offset - 1] == ' ')
3584 offset--;
3585 obstack_blank_fast (&scratch_obstack, offset);
3586
3587 /* B<C<char> >, not B<C<char>> */
3588 if (bufp[offset - 1] == '>')
3589 ccat (' ');
3590 }
3591 ccat ('>');
3592 ccat ('\0');
3593 return (char *) obstack_base (&scratch_obstack);
3594 }
3595
3596 static tree
3597 classtype_mangled_name (t)
3598 tree t;
3599 {
3600 if (CLASSTYPE_TEMPLATE_INFO (t)
3601 /* Specializations have already had their names set up in
3602 lookup_template_class. */
3603 && !CLASSTYPE_TEMPLATE_SPECIALIZATION (t))
3604 {
3605 tree tmpl = most_general_template (CLASSTYPE_TI_TEMPLATE (t));
3606
3607 /* For non-primary templates, the template parameters are
3608 implicit from their surrounding context. */
3609 if (PRIMARY_TEMPLATE_P (tmpl))
3610 {
3611 tree name = DECL_NAME (tmpl);
3612 char *mangled_name = mangle_class_name_for_template
3613 (IDENTIFIER_POINTER (name),
3614 DECL_INNERMOST_TEMPLATE_PARMS (tmpl),
3615 CLASSTYPE_TI_ARGS (t));
3616 tree id = get_identifier (mangled_name);
3617 IDENTIFIER_TEMPLATE (id) = name;
3618 return id;
3619 }
3620 }
3621
3622 return TYPE_IDENTIFIER (t);
3623 }
3624
3625 static void
3626 add_pending_template (d)
3627 tree d;
3628 {
3629 tree ti = (TYPE_P (d)
3630 ? CLASSTYPE_TEMPLATE_INFO (d)
3631 : DECL_TEMPLATE_INFO (d));
3632 int level;
3633
3634 if (TI_PENDING_TEMPLATE_FLAG (ti))
3635 return;
3636
3637 /* We are called both from instantiate_decl, where we've already had a
3638 tinst_level pushed, and instantiate_template, where we haven't.
3639 Compensate. */
3640 level = !(current_tinst_level && TINST_DECL (current_tinst_level) == d);
3641
3642 if (level)
3643 push_tinst_level (d);
3644
3645 *template_tail = tree_cons (current_tinst_level, d, NULL_TREE);
3646 template_tail = &TREE_CHAIN (*template_tail);
3647 TI_PENDING_TEMPLATE_FLAG (ti) = 1;
3648
3649 if (level)
3650 pop_tinst_level ();
3651 }
3652
3653
3654 /* Return a TEMPLATE_ID_EXPR corresponding to the indicated FNS (which
3655 may be either a _DECL or an overloaded function or an
3656 IDENTIFIER_NODE), and ARGLIST. */
3657
3658 tree
3659 lookup_template_function (fns, arglist)
3660 tree fns, arglist;
3661 {
3662 tree type;
3663
3664 if (fns == NULL_TREE)
3665 {
3666 cp_error ("non-template used as template");
3667 return error_mark_node;
3668 }
3669
3670 type = TREE_TYPE (fns);
3671 if (TREE_CODE (fns) == OVERLOAD || !type)
3672 type = unknown_type_node;
3673
3674 if (processing_template_decl)
3675 return build_min (TEMPLATE_ID_EXPR, type, fns, arglist);
3676 else
3677 return build (TEMPLATE_ID_EXPR, type, fns, arglist);
3678 }
3679
3680 /* Within the scope of a template class S<T>, the name S gets bound
3681 (in build_self_reference) to a TYPE_DECL for the class, not a
3682 TEMPLATE_DECL. If DECL is a TYPE_DECL for current_class_type,
3683 or one of its enclosing classes, and that type is a template,
3684 return the associated TEMPLATE_DECL. Otherwise, the original
3685 DECL is returned. */
3686
3687 static tree
3688 maybe_get_template_decl_from_type_decl (decl)
3689 tree decl;
3690 {
3691 return (decl != NULL_TREE
3692 && TREE_CODE (decl) == TYPE_DECL
3693 && DECL_ARTIFICIAL (decl)
3694 && CLASS_TYPE_P (TREE_TYPE (decl))
3695 && CLASSTYPE_TEMPLATE_INFO (TREE_TYPE (decl)))
3696 ? CLASSTYPE_TI_TEMPLATE (TREE_TYPE (decl)) : decl;
3697 }
3698
3699 /* Given an IDENTIFIER_NODE (type TEMPLATE_DECL) and a chain of
3700 parameters, find the desired type.
3701
3702 D1 is the PTYPENAME terminal, and ARGLIST is the list of arguments.
3703 (Actually ARGLIST may be either a TREE_LIST or a TREE_VEC. It will
3704 be a TREE_LIST if called directly from the parser, and a TREE_VEC
3705 otherwise.) Since ARGLIST is build on the temp_decl_obstack, we must
3706 copy it here to keep it from being reclaimed when the decl storage
3707 is reclaimed.
3708
3709 IN_DECL, if non-NULL, is the template declaration we are trying to
3710 instantiate.
3711
3712 If ENTERING_SCOPE is non-zero, we are about to enter the scope of
3713 the class we are looking up.
3714
3715 If the template class is really a local class in a template
3716 function, then the FUNCTION_CONTEXT is the function in which it is
3717 being instantiated. */
3718
3719 tree
3720 lookup_template_class (d1, arglist, in_decl, context, entering_scope)
3721 tree d1, arglist;
3722 tree in_decl;
3723 tree context;
3724 int entering_scope;
3725 {
3726 tree template = NULL_TREE, parmlist;
3727 tree t;
3728
3729 if (TREE_CODE (d1) == IDENTIFIER_NODE)
3730 {
3731 if (IDENTIFIER_VALUE (d1)
3732 && DECL_TEMPLATE_TEMPLATE_PARM_P (IDENTIFIER_VALUE (d1)))
3733 template = IDENTIFIER_VALUE (d1);
3734 else
3735 {
3736 if (context)
3737 push_decl_namespace (context);
3738 template = lookup_name (d1, /*prefer_type=*/0);
3739 template = maybe_get_template_decl_from_type_decl (template);
3740 if (context)
3741 pop_decl_namespace ();
3742 }
3743 if (template)
3744 context = DECL_CONTEXT (template);
3745 }
3746 else if (TREE_CODE (d1) == TYPE_DECL && IS_AGGR_TYPE (TREE_TYPE (d1)))
3747 {
3748 tree type = TREE_TYPE (d1);
3749
3750 /* If we are declaring a constructor, say A<T>::A<T>, we will get
3751 an implicit typename for the second A. Deal with it. */
3752 if (TREE_CODE (type) == TYPENAME_TYPE && TREE_TYPE (type))
3753 type = TREE_TYPE (type);
3754
3755 if (CLASSTYPE_TEMPLATE_INFO (type))
3756 {
3757 template = CLASSTYPE_TI_TEMPLATE (type);
3758 d1 = DECL_NAME (template);
3759 }
3760 }
3761 else if (TREE_CODE (d1) == ENUMERAL_TYPE
3762 || (TYPE_P (d1) && IS_AGGR_TYPE (d1)))
3763 {
3764 template = TYPE_TI_TEMPLATE (d1);
3765 d1 = DECL_NAME (template);
3766 }
3767 else if (TREE_CODE (d1) == TEMPLATE_DECL
3768 && TREE_CODE (DECL_TEMPLATE_RESULT (d1)) == TYPE_DECL)
3769 {
3770 template = d1;
3771 d1 = DECL_NAME (template);
3772 context = DECL_CONTEXT (template);
3773 }
3774 else
3775 my_friendly_abort (272);
3776
3777 /* With something like `template <class T> class X class X { ... };'
3778 we could end up with D1 having nothing but an IDENTIFIER_VALUE.
3779 We don't want to do that, but we have to deal with the situation,
3780 so let's give them some syntax errors to chew on instead of a
3781 crash. */
3782 if (! template)
3783 {
3784 cp_error ("`%T' is not a template", d1);
3785 return error_mark_node;
3786 }
3787
3788 if (TREE_CODE (template) != TEMPLATE_DECL)
3789 {
3790 cp_error ("non-template type `%T' used as a template", d1);
3791 if (in_decl)
3792 cp_error_at ("for template declaration `%D'", in_decl);
3793 return error_mark_node;
3794 }
3795
3796 if (DECL_TEMPLATE_TEMPLATE_PARM_P (template))
3797 {
3798 /* Create a new TEMPLATE_DECL and TEMPLATE_TEMPLATE_PARM node to store
3799 template arguments */
3800
3801 tree parm;
3802 tree arglist2;
3803
3804 parmlist = DECL_INNERMOST_TEMPLATE_PARMS (template);
3805
3806 arglist2 = coerce_template_parms (parmlist, arglist, template, 1, 1);
3807 if (arglist2 == error_mark_node)
3808 return error_mark_node;
3809
3810 parm = copy_template_template_parm (TREE_TYPE (template), arglist2);
3811 TYPE_SIZE (parm) = 0;
3812 return parm;
3813 }
3814 else
3815 {
3816 tree template_type = TREE_TYPE (template);
3817 tree gen_tmpl;
3818 tree type_decl;
3819 tree found = NULL_TREE;
3820 int arg_depth;
3821 int parm_depth;
3822 int is_partial_instantiation;
3823
3824 gen_tmpl = most_general_template (template);
3825 parmlist = DECL_TEMPLATE_PARMS (gen_tmpl);
3826 parm_depth = TMPL_PARMS_DEPTH (parmlist);
3827 arg_depth = TMPL_ARGS_DEPTH (arglist);
3828
3829 if (arg_depth == 1 && parm_depth > 1)
3830 {
3831 /* We've been given an incomplete set of template arguments.
3832 For example, given:
3833
3834 template <class T> struct S1 {
3835 template <class U> struct S2 {};
3836 template <class U> struct S2<U*> {};
3837 };
3838
3839 we will be called with an ARGLIST of `U*', but the
3840 TEMPLATE will be `template <class T> template
3841 <class U> struct S1<T>::S2'. We must fill in the missing
3842 arguments. */
3843 arglist
3844 = add_outermost_template_args (TYPE_TI_ARGS (TREE_TYPE (template)),
3845 arglist);
3846 arg_depth = TMPL_ARGS_DEPTH (arglist);
3847 }
3848
3849 /* Now we should enough arguments. */
3850 my_friendly_assert (parm_depth == arg_depth, 0);
3851
3852 /* From here on, we're only interested in the most general
3853 template. */
3854 template = gen_tmpl;
3855
3856 /* Calculate the BOUND_ARGS. These will be the args that are
3857 actually tsubst'd into the definition to create the
3858 instantiation. */
3859 if (parm_depth > 1)
3860 {
3861 /* We have multiple levels of arguments to coerce, at once. */
3862 int i;
3863 int saved_depth = TMPL_ARGS_DEPTH (arglist);
3864
3865 tree bound_args = make_tree_vec (parm_depth);
3866
3867 for (i = saved_depth,
3868 t = DECL_TEMPLATE_PARMS (template);
3869 i > 0 && t != NULL_TREE;
3870 --i, t = TREE_CHAIN (t))
3871 {
3872 tree a = coerce_template_parms (TREE_VALUE (t),
3873 arglist, template, 1, 1);
3874 SET_TMPL_ARGS_LEVEL (bound_args, i, a);
3875
3876 /* We temporarily reduce the length of the ARGLIST so
3877 that coerce_template_parms will see only the arguments
3878 corresponding to the template parameters it is
3879 examining. */
3880 TREE_VEC_LENGTH (arglist)--;
3881 }
3882
3883 /* Restore the ARGLIST to its full size. */
3884 TREE_VEC_LENGTH (arglist) = saved_depth;
3885
3886 arglist = bound_args;
3887 }
3888 else
3889 arglist
3890 = coerce_template_parms (INNERMOST_TEMPLATE_PARMS (parmlist),
3891 INNERMOST_TEMPLATE_ARGS (arglist),
3892 template, 1, 1);
3893
3894 if (arglist == error_mark_node)
3895 /* We were unable to bind the arguments. */
3896 return error_mark_node;
3897
3898 /* In the scope of a template class, explicit references to the
3899 template class refer to the type of the template, not any
3900 instantiation of it. For example, in:
3901
3902 template <class T> class C { void f(C<T>); }
3903
3904 the `C<T>' is just the same as `C'. Outside of the
3905 class, however, such a reference is an instantiation. */
3906 if (comp_template_args (TYPE_TI_ARGS (template_type),
3907 arglist))
3908 {
3909 found = template_type;
3910
3911 if (!entering_scope && PRIMARY_TEMPLATE_P (template))
3912 {
3913 tree ctx;
3914
3915 /* Note that we use DECL_CONTEXT, rather than
3916 CP_DECL_CONTEXT, so that the termination test is
3917 always just `ctx'. We're not interested in namepace
3918 scopes. */
3919 for (ctx = current_class_type;
3920 ctx;
3921 ctx = (TYPE_P (ctx)) ? TYPE_CONTEXT (ctx) : DECL_CONTEXT (ctx))
3922 if (same_type_p (ctx, template_type))
3923 break;
3924
3925 if (!ctx)
3926 /* We're not in the scope of the class, so the
3927 TEMPLATE_TYPE is not the type we want after
3928 all. */
3929 found = NULL_TREE;
3930 }
3931 }
3932
3933 if (!found)
3934 {
3935 for (found = DECL_TEMPLATE_INSTANTIATIONS (template);
3936 found; found = TREE_CHAIN (found))
3937 if (comp_template_args (TREE_PURPOSE (found), arglist))
3938 break;
3939
3940 if (found)
3941 found = TREE_VALUE (found);
3942 }
3943
3944 if (found)
3945 return found;
3946
3947 /* This type is a "partial instantiation" if any of the template
3948 arguments still inolve template parameters. Note that we set
3949 IS_PARTIAL_INSTANTIATION for partial specializations as
3950 well. */
3951 is_partial_instantiation = uses_template_parms (arglist);
3952
3953 if (!is_partial_instantiation
3954 && !PRIMARY_TEMPLATE_P (template)
3955 && TREE_CODE (CP_DECL_CONTEXT (template)) == NAMESPACE_DECL)
3956 {
3957 found = xref_tag_from_type (TREE_TYPE (template),
3958 DECL_NAME (template),
3959 /*globalize=*/1);
3960 return found;
3961 }
3962
3963 context = tsubst (DECL_CONTEXT (template), arglist,
3964 /*complain=*/0, in_decl);
3965 if (!context)
3966 context = global_namespace;
3967
3968 /* Create the type. */
3969 if (TREE_CODE (template_type) == ENUMERAL_TYPE)
3970 {
3971 if (!is_partial_instantiation)
3972 t = start_enum (TYPE_IDENTIFIER (template_type));
3973 else
3974 /* We don't want to call start_enum for this type, since
3975 the values for the enumeration constants may involve
3976 template parameters. And, no one should be interested
3977 in the enumeration constants for such a type. */
3978 t = make_node (ENUMERAL_TYPE);
3979 }
3980 else
3981 {
3982 t = make_aggr_type (TREE_CODE (template_type));
3983 CLASSTYPE_DECLARED_CLASS (t)
3984 = CLASSTYPE_DECLARED_CLASS (template_type);
3985 CLASSTYPE_GOT_SEMICOLON (t) = 1;
3986 SET_CLASSTYPE_IMPLICIT_INSTANTIATION (t);
3987 TYPE_FOR_JAVA (t) = TYPE_FOR_JAVA (template_type);
3988
3989 /* A local class. Make sure the decl gets registered properly. */
3990 if (context == current_function_decl)
3991 pushtag (DECL_NAME (template), t, 0);
3992 }
3993
3994 /* If we called start_enum or pushtag above, this information
3995 will already be set up. */
3996 if (!TYPE_NAME (t))
3997 {
3998 TYPE_CONTEXT (t) = FROB_CONTEXT (context);
3999
4000 type_decl = create_implicit_typedef (DECL_NAME (template), t);
4001 DECL_CONTEXT (type_decl) = TYPE_CONTEXT (t);
4002 TYPE_STUB_DECL (t) = type_decl;
4003 DECL_SOURCE_FILE (type_decl)
4004 = DECL_SOURCE_FILE (TYPE_STUB_DECL (template_type));
4005 DECL_SOURCE_LINE (type_decl)
4006 = DECL_SOURCE_LINE (TYPE_STUB_DECL (template_type));
4007 }
4008 else
4009 type_decl = TYPE_NAME (t);
4010
4011 /* Set up the template information. We have to figure out which
4012 template is the immediate parent if this is a full
4013 instantiation. */
4014 if (parm_depth == 1 || is_partial_instantiation
4015 || !PRIMARY_TEMPLATE_P (template))
4016 /* This case is easy; there are no member templates involved. */
4017 found = template;
4018 else
4019 {
4020 /* This is a full instantiation of a member template. There
4021 should be some partial instantiation of which this is an
4022 instance. */
4023
4024 for (found = DECL_TEMPLATE_INSTANTIATIONS (template);
4025 found; found = TREE_CHAIN (found))
4026 {
4027 int success;
4028 tree tmpl = CLASSTYPE_TI_TEMPLATE (TREE_VALUE (found));
4029
4030 /* We only want partial instantiations, here, not
4031 specializations or full instantiations. */
4032 if (CLASSTYPE_TEMPLATE_SPECIALIZATION (TREE_VALUE (found))
4033 || !uses_template_parms (TREE_VALUE (found)))
4034 continue;
4035
4036 /* Temporarily reduce by one the number of levels in the
4037 ARGLIST and in FOUND so as to avoid comparing the
4038 last set of arguments. */
4039 TREE_VEC_LENGTH (arglist)--;
4040 TREE_VEC_LENGTH (TREE_PURPOSE (found)) --;
4041
4042 /* See if the arguments match. If they do, then TMPL is
4043 the partial instantiation we want. */
4044 success = comp_template_args (TREE_PURPOSE (found), arglist);
4045
4046 /* Restore the argument vectors to their full size. */
4047 TREE_VEC_LENGTH (arglist)++;
4048 TREE_VEC_LENGTH (TREE_PURPOSE (found))++;
4049
4050 if (success)
4051 {
4052 found = tmpl;
4053 break;
4054 }
4055 }
4056
4057 if (!found)
4058 my_friendly_abort (0);
4059 }
4060
4061 SET_TYPE_TEMPLATE_INFO (t,
4062 tree_cons (found, arglist, NULL_TREE));
4063 DECL_TEMPLATE_INSTANTIATIONS (template)
4064 = tree_cons (arglist, t,
4065 DECL_TEMPLATE_INSTANTIATIONS (template));
4066
4067 if (TREE_CODE (t) == ENUMERAL_TYPE
4068 && !is_partial_instantiation)
4069 /* Now that the type has been registered on the instantiations
4070 list, we set up the enumerators. Because the enumeration
4071 constants may involve the enumeration type itself, we make
4072 sure to register the type first, and then create the
4073 constants. That way, doing tsubst_expr for the enumeration
4074 constants won't result in recursive calls here; we'll find
4075 the instantiation and exit above. */
4076 tsubst_enum (template_type, t, arglist);
4077
4078 /* Reset the name of the type, now that CLASSTYPE_TEMPLATE_INFO
4079 is set up. */
4080 if (TREE_CODE (t) != ENUMERAL_TYPE)
4081 DECL_NAME (type_decl) = classtype_mangled_name (t);
4082 DECL_ASSEMBLER_NAME (type_decl) = DECL_NAME (type_decl);
4083 if (!is_partial_instantiation)
4084 {
4085 if (flag_new_abi)
4086 DECL_ASSEMBLER_NAME (type_decl) = mangle_decl (type_decl);
4087 else
4088 DECL_ASSEMBLER_NAME (type_decl)
4089 = get_identifier (build_overload_name (t, 1, 1));
4090
4091 /* For backwards compatibility; code that uses
4092 -fexternal-templates expects looking up a template to
4093 instantiate it. I think DDD still relies on this.
4094 (jason 8/20/1998) */
4095 if (TREE_CODE (t) != ENUMERAL_TYPE
4096 && flag_external_templates
4097 && CLASSTYPE_INTERFACE_KNOWN (TREE_TYPE (template))
4098 && ! CLASSTYPE_INTERFACE_ONLY (TREE_TYPE (template)))
4099 add_pending_template (t);
4100 }
4101 else
4102 /* If the type makes use of template parameters, the
4103 code that generates debugging information will crash. */
4104 DECL_IGNORED_P (TYPE_STUB_DECL (t)) = 1;
4105
4106 return t;
4107 }
4108 }
4109 \f
4110 struct pair_fn_data
4111 {
4112 tree_fn_t fn;
4113 void *data;
4114 };
4115
4116 /* Called from for_each_template_parm via walk_tree. */
4117
4118 static tree
4119 for_each_template_parm_r (tp, walk_subtrees, d)
4120 tree *tp;
4121 int *walk_subtrees;
4122 void *d;
4123 {
4124 tree t = *tp;
4125 struct pair_fn_data *pfd = (struct pair_fn_data *) d;
4126 tree_fn_t fn = pfd->fn;
4127 void *data = pfd->data;
4128
4129 if (TYPE_P (t)
4130 && for_each_template_parm (TYPE_CONTEXT (t), fn, data))
4131 return error_mark_node;
4132
4133 switch (TREE_CODE (t))
4134 {
4135 case RECORD_TYPE:
4136 if (TYPE_PTRMEMFUNC_FLAG (t))
4137 break;
4138 /* Fall through. */
4139
4140 case UNION_TYPE:
4141 case ENUMERAL_TYPE:
4142 if (!TYPE_TEMPLATE_INFO (t))
4143 *walk_subtrees = 0;
4144 else if (for_each_template_parm (TREE_VALUE (TYPE_TEMPLATE_INFO (t)),
4145 fn, data))
4146 return error_mark_node;
4147 break;
4148
4149 case METHOD_TYPE:
4150 /* Since we're not going to walk subtrees, we have to do this
4151 explicitly here. */
4152 if (for_each_template_parm (TYPE_METHOD_BASETYPE (t), fn, data))
4153 return error_mark_node;
4154
4155 case FUNCTION_TYPE:
4156 /* Check the return type. */
4157 if (for_each_template_parm (TREE_TYPE (t), fn, data))
4158 return error_mark_node;
4159
4160 /* Check the parameter types. Since default arguments are not
4161 instantiated until they are needed, the TYPE_ARG_TYPES may
4162 contain expressions that involve template parameters. But,
4163 no-one should be looking at them yet. And, once they're
4164 instantiated, they don't contain template parameters, so
4165 there's no point in looking at them then, either. */
4166 {
4167 tree parm;
4168
4169 for (parm = TYPE_ARG_TYPES (t); parm; parm = TREE_CHAIN (parm))
4170 if (for_each_template_parm (TREE_VALUE (parm), fn, data))
4171 return error_mark_node;
4172
4173 /* Since we've already handled the TYPE_ARG_TYPES, we don't
4174 want walk_tree walking into them itself. */
4175 *walk_subtrees = 0;
4176 }
4177 break;
4178
4179 case FUNCTION_DECL:
4180 case VAR_DECL:
4181 if (DECL_LANG_SPECIFIC (t) && DECL_TEMPLATE_INFO (t)
4182 && for_each_template_parm (DECL_TI_ARGS (t), fn, data))
4183 return error_mark_node;
4184 /* Fall through. */
4185
4186 case CONST_DECL:
4187 case PARM_DECL:
4188 if (DECL_CONTEXT (t)
4189 && for_each_template_parm (DECL_CONTEXT (t), fn, data))
4190 return error_mark_node;
4191 break;
4192
4193 case TEMPLATE_TEMPLATE_PARM:
4194 /* Record template parameters such as `T' inside `TT<T>'. */
4195 if (TEMPLATE_TEMPLATE_PARM_TEMPLATE_INFO (t)
4196 && for_each_template_parm (TYPE_TI_ARGS (t), fn, data))
4197 return error_mark_node;
4198 /* Fall through. */
4199
4200 case TEMPLATE_TYPE_PARM:
4201 case TEMPLATE_PARM_INDEX:
4202 if (fn && (*fn)(t, data))
4203 return error_mark_node;
4204 else if (!fn)
4205 return error_mark_node;
4206 break;
4207
4208 case TEMPLATE_DECL:
4209 /* A template template parameter is encountered */
4210 if (DECL_TEMPLATE_TEMPLATE_PARM_P (t)
4211 && for_each_template_parm (TREE_TYPE (t), fn, data))
4212 return error_mark_node;
4213
4214 /* Already substituted template template parameter */
4215 *walk_subtrees = 0;
4216 break;
4217
4218 case TYPENAME_TYPE:
4219 if (!fn || for_each_template_parm (TYPENAME_TYPE_FULLNAME (t), fn, data))
4220 return error_mark_node;
4221 break;
4222
4223 case CONSTRUCTOR:
4224 if (TREE_TYPE (t) && TYPE_PTRMEMFUNC_P (TREE_TYPE (t))
4225 && for_each_template_parm (TYPE_PTRMEMFUNC_FN_TYPE
4226 (TREE_TYPE (t)), fn, data))
4227 return error_mark_node;
4228 break;
4229
4230 case INDIRECT_REF:
4231 case COMPONENT_REF:
4232 /* If there's no type, then this thing must be some expression
4233 involving template parameters. */
4234 if (!fn && !TREE_TYPE (t))
4235 return error_mark_node;
4236 break;
4237
4238 case MODOP_EXPR:
4239 case CAST_EXPR:
4240 case REINTERPRET_CAST_EXPR:
4241 case CONST_CAST_EXPR:
4242 case STATIC_CAST_EXPR:
4243 case DYNAMIC_CAST_EXPR:
4244 case ARROW_EXPR:
4245 case DOTSTAR_EXPR:
4246 case TYPEID_EXPR:
4247 case LOOKUP_EXPR:
4248 case PSEUDO_DTOR_EXPR:
4249 if (!fn)
4250 return error_mark_node;
4251 break;
4252
4253 default:
4254 break;
4255 }
4256
4257 /* We didn't find any template parameters we liked. */
4258 return NULL_TREE;
4259 }
4260
4261 /* For each TEMPLATE_TYPE_PARM, TEMPLATE_TEMPLATE_PARM, or
4262 TEMPLATE_PARM_INDEX in T, call FN with the parameter and the DATA.
4263 If FN returns non-zero, the iteration is terminated, and
4264 for_each_template_parm returns 1. Otherwise, the iteration
4265 continues. If FN never returns a non-zero value, the value
4266 returned by for_each_template_parm is 0. If FN is NULL, it is
4267 considered to be the function which always returns 1. */
4268
4269 static int
4270 for_each_template_parm (t, fn, data)
4271 tree t;
4272 tree_fn_t fn;
4273 void* data;
4274 {
4275 struct pair_fn_data pfd;
4276
4277 /* Set up. */
4278 pfd.fn = fn;
4279 pfd.data = data;
4280
4281 /* Walk the tree. */
4282 return walk_tree (&t, for_each_template_parm_r, &pfd) != NULL_TREE;
4283 }
4284
4285 int
4286 uses_template_parms (t)
4287 tree t;
4288 {
4289 return for_each_template_parm (t, 0, 0);
4290 }
4291
4292 static int tinst_depth;
4293 extern int max_tinst_depth;
4294 #ifdef GATHER_STATISTICS
4295 int depth_reached;
4296 #endif
4297 static int tinst_level_tick;
4298 static int last_template_error_tick;
4299
4300 /* Print out all the template instantiations that we are currently
4301 working on. If ERR, we are being called from cp_thing, so do
4302 the right thing for an error message. */
4303
4304 static void
4305 print_template_context (err)
4306 int err;
4307 {
4308 tree p = current_tinst_level;
4309 int line = lineno;
4310 const char *file = input_filename;
4311
4312 if (err && p)
4313 {
4314 if (current_function_decl != TINST_DECL (p)
4315 && current_function_decl != NULL_TREE)
4316 /* We can get here during the processing of some synthesized
4317 method. Then, TINST_DECL (p) will be the function that's causing
4318 the synthesis. */
4319 ;
4320 else
4321 {
4322 if (current_function_decl == TINST_DECL (p))
4323 /* Avoid redundancy with the the "In function" line. */;
4324 else
4325 fprintf (stderr, "%s: In instantiation of `%s':\n",
4326 file, decl_as_string (TINST_DECL (p),
4327 TS_DECL_TYPE | TS_FUNC_NORETURN));
4328
4329 line = TINST_LINE (p);
4330 file = TINST_FILE (p);
4331 p = TREE_CHAIN (p);
4332 }
4333 }
4334
4335 for (; p; p = TREE_CHAIN (p))
4336 {
4337 fprintf (stderr, "%s:%d: instantiated from `%s'\n", file, line,
4338 decl_as_string (TINST_DECL (p),
4339 TS_DECL_TYPE | TS_FUNC_NORETURN));
4340 line = TINST_LINE (p);
4341 file = TINST_FILE (p);
4342 }
4343 fprintf (stderr, "%s:%d: instantiated from here\n", file, line);
4344 }
4345
4346 /* Called from cp_thing to print the template context for an error. */
4347
4348 void
4349 maybe_print_template_context ()
4350 {
4351 if (last_template_error_tick == tinst_level_tick
4352 || current_tinst_level == 0)
4353 return;
4354
4355 last_template_error_tick = tinst_level_tick;
4356 print_template_context (1);
4357 }
4358
4359 /* We're starting to instantiate D; record the template instantiation context
4360 for diagnostics and to restore it later. */
4361
4362 static int
4363 push_tinst_level (d)
4364 tree d;
4365 {
4366 tree new;
4367
4368 if (tinst_depth >= max_tinst_depth)
4369 {
4370 /* If the instantiation in question still has unbound template parms,
4371 we don't really care if we can't instantiate it, so just return.
4372 This happens with base instantiation for implicit `typename'. */
4373 if (uses_template_parms (d))
4374 return 0;
4375
4376 last_template_error_tick = tinst_level_tick;
4377 cp_error ("template instantiation depth exceeds maximum of %d (use -ftemplate-depth-NN to increase the maximum) instantiating `%D'",
4378 max_tinst_depth, d);
4379
4380 print_template_context (0);
4381
4382 return 0;
4383 }
4384
4385 new = build_expr_wfl (d, input_filename, lineno, 0);
4386 TREE_CHAIN (new) = current_tinst_level;
4387 current_tinst_level = new;
4388
4389 ++tinst_depth;
4390 #ifdef GATHER_STATISTICS
4391 if (tinst_depth > depth_reached)
4392 depth_reached = tinst_depth;
4393 #endif
4394
4395 ++tinst_level_tick;
4396 return 1;
4397 }
4398
4399 /* We're done instantiating this template; return to the instantiation
4400 context. */
4401
4402 void
4403 pop_tinst_level ()
4404 {
4405 tree old = current_tinst_level;
4406
4407 /* Restore the filename and line number stashed away when we started
4408 this instantiation. */
4409 lineno = TINST_LINE (old);
4410 input_filename = TINST_FILE (old);
4411 extract_interface_info ();
4412
4413 current_tinst_level = TREE_CHAIN (old);
4414 --tinst_depth;
4415 ++tinst_level_tick;
4416 }
4417
4418 /* We're instantiating a deferred template; restore the template
4419 instantiation context in which the instantiation was requested, which
4420 is one step out from LEVEL. */
4421
4422 static void
4423 reopen_tinst_level (level)
4424 tree level;
4425 {
4426 tree t;
4427
4428 tinst_depth = 0;
4429 for (t = level; t; t = TREE_CHAIN (t))
4430 ++tinst_depth;
4431
4432 current_tinst_level = level;
4433 pop_tinst_level ();
4434 }
4435
4436 /* Return the outermost template instantiation context, for use with
4437 -falt-external-templates. */
4438
4439 tree
4440 tinst_for_decl ()
4441 {
4442 tree p = current_tinst_level;
4443
4444 if (p)
4445 for (; TREE_CHAIN (p) ; p = TREE_CHAIN (p))
4446 ;
4447 return p;
4448 }
4449
4450 /* DECL is a friend FUNCTION_DECL or TEMPLATE_DECL. ARGS is the
4451 vector of template arguments, as for tsubst.
4452
4453 Returns an appropriate tsbust'd friend declaration. */
4454
4455 static tree
4456 tsubst_friend_function (decl, args)
4457 tree decl;
4458 tree args;
4459 {
4460 tree new_friend;
4461 int line = lineno;
4462 const char *file = input_filename;
4463
4464 lineno = DECL_SOURCE_LINE (decl);
4465 input_filename = DECL_SOURCE_FILE (decl);
4466
4467 if (TREE_CODE (decl) == FUNCTION_DECL
4468 && DECL_TEMPLATE_INSTANTIATION (decl)
4469 && TREE_CODE (DECL_TI_TEMPLATE (decl)) != TEMPLATE_DECL)
4470 /* This was a friend declared with an explicit template
4471 argument list, e.g.:
4472
4473 friend void f<>(T);
4474
4475 to indicate that f was a template instantiation, not a new
4476 function declaration. Now, we have to figure out what
4477 instantiation of what template. */
4478 {
4479 tree template_id;
4480 tree new_args;
4481 tree tmpl;
4482
4483 template_id
4484 = lookup_template_function (tsubst_expr (DECL_TI_TEMPLATE (decl),
4485 args, /*complain=*/1,
4486 NULL_TREE),
4487 tsubst (DECL_TI_ARGS (decl),
4488 args, /*complain=*/1,
4489 NULL_TREE));
4490 new_friend = tsubst (decl, args, /*complain=*/1, NULL_TREE);
4491 tmpl = determine_specialization (template_id, new_friend,
4492 &new_args,
4493 /*need_member_template=*/0);
4494 new_friend = instantiate_template (tmpl, new_args);
4495 goto done;
4496 }
4497
4498 new_friend = tsubst (decl, args, /*complain=*/1, NULL_TREE);
4499
4500 /* The NEW_FRIEND will look like an instantiation, to the
4501 compiler, but is not an instantiation from the point of view of
4502 the language. For example, we might have had:
4503
4504 template <class T> struct S {
4505 template <class U> friend void f(T, U);
4506 };
4507
4508 Then, in S<int>, template <class U> void f(int, U) is not an
4509 instantiation of anything. */
4510 DECL_USE_TEMPLATE (new_friend) = 0;
4511 if (TREE_CODE (decl) == TEMPLATE_DECL)
4512 {
4513 DECL_USE_TEMPLATE (DECL_TEMPLATE_RESULT (new_friend)) = 0;
4514 DECL_SAVED_TREE (DECL_TEMPLATE_RESULT (new_friend))
4515 = DECL_SAVED_TREE (DECL_TEMPLATE_RESULT (decl));
4516 }
4517
4518 /* The mangled name for the NEW_FRIEND is incorrect. The call to
4519 tsubst will have resulted in a call to
4520 set_mangled_name_for_template_decl. But, the function is not a
4521 template instantiation and should not be mangled like one.
4522 Therefore, we remangle the function name. We don't have to do
4523 this if the NEW_FRIEND is a template since
4524 set_mangled_name_for_template_decl doesn't do anything if the
4525 function declaration still uses template arguments. */
4526 if (TREE_CODE (new_friend) != TEMPLATE_DECL)
4527 {
4528 set_mangled_name_for_decl (new_friend);
4529 DECL_RTL (new_friend) = 0;
4530 make_decl_rtl (new_friend, NULL_PTR, 1);
4531 }
4532
4533 if (DECL_NAMESPACE_SCOPE_P (new_friend))
4534 {
4535 tree old_decl;
4536 tree new_friend_template_info;
4537 tree new_friend_result_template_info;
4538 tree ns;
4539 int new_friend_is_defn;
4540
4541 /* We must save some information from NEW_FRIEND before calling
4542 duplicate decls since that function will free NEW_FRIEND if
4543 possible. */
4544 new_friend_template_info = DECL_TEMPLATE_INFO (new_friend);
4545 if (TREE_CODE (new_friend) == TEMPLATE_DECL)
4546 {
4547 /* This declaration is a `primary' template. */
4548 DECL_PRIMARY_TEMPLATE (new_friend) = new_friend;
4549
4550 new_friend_is_defn
4551 = DECL_INITIAL (DECL_TEMPLATE_RESULT (new_friend)) != NULL_TREE;
4552 new_friend_result_template_info
4553 = DECL_TEMPLATE_INFO (DECL_TEMPLATE_RESULT (new_friend));
4554 }
4555 else
4556 {
4557 new_friend_is_defn = DECL_INITIAL (new_friend) != NULL_TREE;
4558 new_friend_result_template_info = NULL_TREE;
4559 }
4560
4561 /* Inside pushdecl_namespace_level, we will push into the
4562 current namespace. However, the friend function should go
4563 into the namespace of the template. */
4564 ns = decl_namespace_context (new_friend);
4565 push_nested_namespace (ns);
4566 old_decl = pushdecl_namespace_level (new_friend);
4567 pop_nested_namespace (ns);
4568
4569 if (old_decl != new_friend)
4570 {
4571 /* This new friend declaration matched an existing
4572 declaration. For example, given:
4573
4574 template <class T> void f(T);
4575 template <class U> class C {
4576 template <class T> friend void f(T) {}
4577 };
4578
4579 the friend declaration actually provides the definition
4580 of `f', once C has been instantiated for some type. So,
4581 old_decl will be the out-of-class template declaration,
4582 while new_friend is the in-class definition.
4583
4584 But, if `f' was called before this point, the
4585 instantiation of `f' will have DECL_TI_ARGS corresponding
4586 to `T' but not to `U', references to which might appear
4587 in the definition of `f'. Previously, the most general
4588 template for an instantiation of `f' was the out-of-class
4589 version; now it is the in-class version. Therefore, we
4590 run through all specialization of `f', adding to their
4591 DECL_TI_ARGS appropriately. In particular, they need a
4592 new set of outer arguments, corresponding to the
4593 arguments for this class instantiation.
4594
4595 The same situation can arise with something like this:
4596
4597 friend void f(int);
4598 template <class T> class C {
4599 friend void f(T) {}
4600 };
4601
4602 when `C<int>' is instantiated. Now, `f(int)' is defined
4603 in the class. */
4604
4605 if (!new_friend_is_defn)
4606 /* On the other hand, if the in-class declaration does
4607 *not* provide a definition, then we don't want to alter
4608 existing definitions. We can just leave everything
4609 alone. */
4610 ;
4611 else
4612 {
4613 /* Overwrite whatever template info was there before, if
4614 any, with the new template information pertaining to
4615 the declaration. */
4616 DECL_TEMPLATE_INFO (old_decl) = new_friend_template_info;
4617
4618 if (TREE_CODE (old_decl) != TEMPLATE_DECL)
4619 /* duplicate_decls will take care of this case. */
4620 ;
4621 else
4622 {
4623 tree t;
4624 tree new_friend_args;
4625
4626 DECL_TEMPLATE_INFO (DECL_TEMPLATE_RESULT (old_decl))
4627 = new_friend_result_template_info;
4628
4629 new_friend_args = TI_ARGS (new_friend_template_info);
4630 for (t = DECL_TEMPLATE_SPECIALIZATIONS (old_decl);
4631 t != NULL_TREE;
4632 t = TREE_CHAIN (t))
4633 {
4634 tree spec = TREE_VALUE (t);
4635
4636 DECL_TI_ARGS (spec)
4637 = add_outermost_template_args (new_friend_args,
4638 DECL_TI_ARGS (spec));
4639 }
4640
4641 /* Now, since specializations are always supposed to
4642 hang off of the most general template, we must move
4643 them. */
4644 t = most_general_template (old_decl);
4645 if (t != old_decl)
4646 {
4647 DECL_TEMPLATE_SPECIALIZATIONS (t)
4648 = chainon (DECL_TEMPLATE_SPECIALIZATIONS (t),
4649 DECL_TEMPLATE_SPECIALIZATIONS (old_decl));
4650 DECL_TEMPLATE_SPECIALIZATIONS (old_decl) = NULL_TREE;
4651 }
4652 }
4653 }
4654
4655 /* The information from NEW_FRIEND has been merged into OLD_DECL
4656 by duplicate_decls. */
4657 new_friend = old_decl;
4658 }
4659 }
4660 else if (COMPLETE_TYPE_P (DECL_CONTEXT (new_friend)))
4661 {
4662 /* Check to see that the declaration is really present, and,
4663 possibly obtain an improved declaration. */
4664 tree fn = check_classfn (DECL_CONTEXT (new_friend),
4665 new_friend);
4666
4667 if (fn)
4668 new_friend = fn;
4669 }
4670
4671 done:
4672 lineno = line;
4673 input_filename = file;
4674 return new_friend;
4675 }
4676
4677 /* FRIEND_TMPL is a friend TEMPLATE_DECL. ARGS is the vector of
4678 template arguments, as for tsubst.
4679
4680 Returns an appropriate tsbust'd friend type. */
4681
4682 static tree
4683 tsubst_friend_class (friend_tmpl, args)
4684 tree friend_tmpl;
4685 tree args;
4686 {
4687 tree friend_type;
4688 tree tmpl;
4689
4690 /* First, we look for a class template. */
4691 tmpl = lookup_name (DECL_NAME (friend_tmpl), /*prefer_type=*/0);
4692
4693 /* But, if we don't find one, it might be because we're in a
4694 situation like this:
4695
4696 template <class T>
4697 struct S {
4698 template <class U>
4699 friend struct S;
4700 };
4701
4702 Here, in the scope of (say) S<int>, `S' is bound to a TYPE_DECL
4703 for `S<int>', not the TEMPLATE_DECL. */
4704 if (!tmpl || !DECL_CLASS_TEMPLATE_P (tmpl))
4705 {
4706 tmpl = lookup_name (DECL_NAME (friend_tmpl), /*prefer_type=*/1);
4707 tmpl = maybe_get_template_decl_from_type_decl (tmpl);
4708 }
4709
4710 if (tmpl && DECL_CLASS_TEMPLATE_P (tmpl))
4711 {
4712 /* The friend template has already been declared. Just
4713 check to see that the declarations match, and install any new
4714 default parameters. We must tsubst the default parameters,
4715 of course. We only need the innermost template parameters
4716 because that is all that redeclare_class_template will look
4717 at. */
4718 tree parms
4719 = tsubst_template_parms (DECL_TEMPLATE_PARMS (friend_tmpl),
4720 args, /*complain=*/1);
4721 redeclare_class_template (TREE_TYPE (tmpl), parms);
4722 friend_type = TREE_TYPE (tmpl);
4723 }
4724 else
4725 {
4726 /* The friend template has not already been declared. In this
4727 case, the instantiation of the template class will cause the
4728 injection of this template into the global scope. */
4729 tmpl = tsubst (friend_tmpl, args, /*complain=*/1, NULL_TREE);
4730
4731 /* The new TMPL is not an instantiation of anything, so we
4732 forget its origins. We don't reset CLASSTYPE_TI_TEMPLATE for
4733 the new type because that is supposed to be the corresponding
4734 template decl, i.e., TMPL. */
4735 DECL_USE_TEMPLATE (tmpl) = 0;
4736 DECL_TEMPLATE_INFO (tmpl) = NULL_TREE;
4737 CLASSTYPE_USE_TEMPLATE (TREE_TYPE (tmpl)) = 0;
4738
4739 /* Inject this template into the global scope. */
4740 friend_type = TREE_TYPE (pushdecl_top_level (tmpl));
4741 }
4742
4743 return friend_type;
4744 }
4745
4746 tree
4747 instantiate_class_template (type)
4748 tree type;
4749 {
4750 tree template, args, pattern, t;
4751 tree typedecl;
4752
4753 if (type == error_mark_node)
4754 return error_mark_node;
4755
4756 if (TYPE_BEING_DEFINED (type) || COMPLETE_TYPE_P (type))
4757 return type;
4758
4759 /* Figure out which template is being instantiated. */
4760 template = most_general_template (CLASSTYPE_TI_TEMPLATE (type));
4761 my_friendly_assert (TREE_CODE (template) == TEMPLATE_DECL, 279);
4762
4763 /* Figure out which arguments are being used to do the
4764 instantiation. */
4765 args = CLASSTYPE_TI_ARGS (type);
4766 PARTIAL_INSTANTIATION_P (type) = uses_template_parms (args);
4767
4768 if (pedantic && PARTIAL_INSTANTIATION_P (type))
4769 /* If this is a partial instantiation, then we can't instantiate
4770 the type; there's no telling whether or not one of the
4771 template parameters might eventually be instantiated to some
4772 value that results in a specialization being used. For
4773 example, consider:
4774
4775 template <class T>
4776 struct S {};
4777
4778 template <class U>
4779 void f(S<U>);
4780
4781 template <>
4782 struct S<int> {};
4783
4784 Now, the `S<U>' in `f<int>' is the specialization, not an
4785 instantiation of the original template. */
4786 return type;
4787
4788 /* Determine what specialization of the original template to
4789 instantiate. */
4790 if (PARTIAL_INSTANTIATION_P (type))
4791 /* There's no telling which specialization is appropriate at this
4792 point. Since all peeking at the innards of this partial
4793 instantiation are extensions (like the "implicit typename"
4794 extension, which allows users to omit the keyword `typename' on
4795 names that are declared as types in template base classes), we
4796 are free to do what we please.
4797
4798 Trying to figure out which partial instantiation to use can
4799 cause a crash. (Some of the template arguments don't even have
4800 types.) So, we just use the most general version. */
4801 t = NULL_TREE;
4802 else
4803 {
4804 t = most_specialized_class (template, args);
4805
4806 if (t == error_mark_node)
4807 {
4808 const char *str = "candidates are:";
4809 cp_error ("ambiguous class template instantiation for `%#T'", type);
4810 for (t = DECL_TEMPLATE_SPECIALIZATIONS (template); t;
4811 t = TREE_CHAIN (t))
4812 {
4813 if (get_class_bindings (TREE_VALUE (t), TREE_PURPOSE (t),
4814 args))
4815 {
4816 cp_error_at ("%s %+#T", str, TREE_TYPE (t));
4817 str = " ";
4818 }
4819 }
4820 TYPE_BEING_DEFINED (type) = 1;
4821 return error_mark_node;
4822 }
4823 }
4824
4825 if (t)
4826 pattern = TREE_TYPE (t);
4827 else
4828 pattern = TREE_TYPE (template);
4829
4830 /* If the template we're instantiating is incomplete, then clearly
4831 there's nothing we can do. */
4832 if (!COMPLETE_TYPE_P (pattern))
4833 return type;
4834
4835 /* If this is a partial instantiation, don't tsubst anything. We will
4836 only use this type for implicit typename, so the actual contents don't
4837 matter. All that matters is whether a particular name is a type. */
4838 if (PARTIAL_INSTANTIATION_P (type))
4839 {
4840 /* The fields set here must be kept in sync with those cleared
4841 in begin_class_definition. */
4842 TYPE_BINFO_BASETYPES (type) = TYPE_BINFO_BASETYPES (pattern);
4843 TYPE_FIELDS (type) = TYPE_FIELDS (pattern);
4844 TYPE_METHODS (type) = TYPE_METHODS (pattern);
4845 CLASSTYPE_TAGS (type) = CLASSTYPE_TAGS (pattern);
4846 CLASSTYPE_VBASECLASSES (type) = CLASSTYPE_VBASECLASSES (pattern);
4847
4848 /* Pretend that the type is complete, so that we will look
4849 inside it during name lookup and such. */
4850 TYPE_SIZE (type) = bitsize_zero_node;
4851 return type;
4852 }
4853
4854 /* If we've recursively instantiated too many templates, stop. */
4855 if (! push_tinst_level (type))
4856 return type;
4857
4858 /* Now we're really doing the instantiation. Mark the type as in
4859 the process of being defined. */
4860 TYPE_BEING_DEFINED (type) = 1;
4861
4862 maybe_push_to_top_level (uses_template_parms (type));
4863
4864 if (t)
4865 {
4866 /* This TYPE is actually a instantiation of of a partial
4867 specialization. We replace the innermost set of ARGS with
4868 the arguments appropriate for substitution. For example,
4869 given:
4870
4871 template <class T> struct S {};
4872 template <class T> struct S<T*> {};
4873
4874 and supposing that we are instantiating S<int*>, ARGS will
4875 present be {int*} but we need {int}. */
4876 tree inner_args
4877 = get_class_bindings (TREE_VALUE (t), TREE_PURPOSE (t),
4878 args);
4879
4880 /* If there were multiple levels in ARGS, replacing the
4881 innermost level would alter CLASSTYPE_TI_ARGS, which we don't
4882 want, so we make a copy first. */
4883 if (TMPL_ARGS_HAVE_MULTIPLE_LEVELS (args))
4884 {
4885 args = copy_node (args);
4886 SET_TMPL_ARGS_LEVEL (args, TMPL_ARGS_DEPTH (args), inner_args);
4887 }
4888 else
4889 args = inner_args;
4890 }
4891
4892 if (flag_external_templates)
4893 {
4894 if (flag_alt_external_templates)
4895 {
4896 CLASSTYPE_INTERFACE_ONLY (type) = interface_only;
4897 SET_CLASSTYPE_INTERFACE_UNKNOWN_X (type, interface_unknown);
4898 CLASSTYPE_VTABLE_NEEDS_WRITING (type)
4899 = (! CLASSTYPE_INTERFACE_ONLY (type)
4900 && CLASSTYPE_INTERFACE_KNOWN (type));
4901 }
4902 else
4903 {
4904 CLASSTYPE_INTERFACE_ONLY (type) = CLASSTYPE_INTERFACE_ONLY (pattern);
4905 SET_CLASSTYPE_INTERFACE_UNKNOWN_X
4906 (type, CLASSTYPE_INTERFACE_UNKNOWN (pattern));
4907 CLASSTYPE_VTABLE_NEEDS_WRITING (type)
4908 = (! CLASSTYPE_INTERFACE_ONLY (type)
4909 && CLASSTYPE_INTERFACE_KNOWN (type));
4910 }
4911 }
4912 else
4913 {
4914 SET_CLASSTYPE_INTERFACE_UNKNOWN (type);
4915 CLASSTYPE_VTABLE_NEEDS_WRITING (type) = 1;
4916 }
4917
4918 TYPE_HAS_CONSTRUCTOR (type) = TYPE_HAS_CONSTRUCTOR (pattern);
4919 TYPE_HAS_DESTRUCTOR (type) = TYPE_HAS_DESTRUCTOR (pattern);
4920 TYPE_OVERLOADS_CALL_EXPR (type) = TYPE_OVERLOADS_CALL_EXPR (pattern);
4921 TYPE_OVERLOADS_ARRAY_REF (type) = TYPE_OVERLOADS_ARRAY_REF (pattern);
4922 TYPE_OVERLOADS_ARROW (type) = TYPE_OVERLOADS_ARROW (pattern);
4923 TYPE_HAS_NEW_OPERATOR (type) = TYPE_HAS_NEW_OPERATOR (pattern);
4924 TYPE_HAS_ARRAY_NEW_OPERATOR (type) = TYPE_HAS_ARRAY_NEW_OPERATOR (pattern);
4925 TYPE_GETS_DELETE (type) = TYPE_GETS_DELETE (pattern);
4926 TYPE_VEC_DELETE_TAKES_SIZE (type) = TYPE_VEC_DELETE_TAKES_SIZE (pattern);
4927 TYPE_HAS_ASSIGN_REF (type) = TYPE_HAS_ASSIGN_REF (pattern);
4928 TYPE_HAS_CONST_ASSIGN_REF (type) = TYPE_HAS_CONST_ASSIGN_REF (pattern);
4929 TYPE_HAS_ABSTRACT_ASSIGN_REF (type) = TYPE_HAS_ABSTRACT_ASSIGN_REF (pattern);
4930 TYPE_HAS_INIT_REF (type) = TYPE_HAS_INIT_REF (pattern);
4931 TYPE_HAS_CONST_INIT_REF (type) = TYPE_HAS_CONST_INIT_REF (pattern);
4932 TYPE_HAS_DEFAULT_CONSTRUCTOR (type) = TYPE_HAS_DEFAULT_CONSTRUCTOR (pattern);
4933 TYPE_HAS_CONVERSION (type) = TYPE_HAS_CONVERSION (pattern);
4934 TYPE_BASE_CONVS_MAY_REQUIRE_CODE_P (type)
4935 = TYPE_BASE_CONVS_MAY_REQUIRE_CODE_P (pattern);
4936 TYPE_USES_MULTIPLE_INHERITANCE (type)
4937 = TYPE_USES_MULTIPLE_INHERITANCE (pattern);
4938 TYPE_USES_VIRTUAL_BASECLASSES (type)
4939 = TYPE_USES_VIRTUAL_BASECLASSES (pattern);
4940 TYPE_PACKED (type) = TYPE_PACKED (pattern);
4941 TYPE_ALIGN (type) = TYPE_ALIGN (pattern);
4942 TYPE_USER_ALIGN (type) = TYPE_USER_ALIGN (pattern);
4943 TYPE_FOR_JAVA (type) = TYPE_FOR_JAVA (pattern); /* For libjava's JArray<T> */
4944 if (ANON_AGGR_TYPE_P (pattern))
4945 SET_ANON_AGGR_TYPE_P (type);
4946
4947 if (TYPE_BINFO_BASETYPES (pattern))
4948 {
4949 tree base_list = NULL_TREE;
4950 tree pbases = TYPE_BINFO_BASETYPES (pattern);
4951 int i;
4952
4953 /* Substitute into each of the bases to determine the actual
4954 basetypes. */
4955 for (i = 0; i < TREE_VEC_LENGTH (pbases); ++i)
4956 {
4957 tree base;
4958 tree access;
4959 tree pbase;
4960
4961 pbase = TREE_VEC_ELT (pbases, i);
4962
4963 /* Substitue to figure out the base class. */
4964 base = tsubst (BINFO_TYPE (pbase), args,
4965 /*complain=*/1, NULL_TREE);
4966 if (base == error_mark_node)
4967 continue;
4968
4969 /* Calculate the correct access node. */
4970 if (TREE_VIA_VIRTUAL (pbase))
4971 {
4972 if (TREE_VIA_PUBLIC (pbase))
4973 access = access_public_virtual_node;
4974 else if (TREE_VIA_PROTECTED (pbase))
4975 access = access_protected_virtual_node;
4976 else
4977 access = access_private_virtual_node;
4978 }
4979 else
4980 {
4981 if (TREE_VIA_PUBLIC (pbase))
4982 access = access_public_node;
4983 else if (TREE_VIA_PROTECTED (pbase))
4984 access = access_protected_node;
4985 else
4986 access = access_private_node;
4987 }
4988
4989 base_list = tree_cons (access, base, base_list);
4990 }
4991
4992 /* The list is now in reverse order; correct that. */
4993 base_list = nreverse (base_list);
4994
4995 /* Now call xref_basetypes to set up all the base-class
4996 information. */
4997 xref_basetypes (TREE_CODE (pattern) == RECORD_TYPE
4998 ? (CLASSTYPE_DECLARED_CLASS (pattern)
4999 ? class_type_node : record_type_node)
5000 : union_type_node,
5001 DECL_NAME (TYPE_NAME (pattern)),
5002 type,
5003 base_list);
5004 }
5005
5006 /* Now that our base classes are set up, enter the scope of the
5007 class, so that name lookups into base classes, etc. will work
5008 corectly. This is precisely analagous to what we do in
5009 begin_class_definition when defining an ordinary non-template
5010 class. */
5011 pushclass (type, 1);
5012
5013 for (t = CLASSTYPE_TAGS (pattern); t; t = TREE_CHAIN (t))
5014 {
5015 tree tag = TREE_VALUE (t);
5016 tree name = TYPE_IDENTIFIER (tag);
5017 tree newtag;
5018
5019 newtag = tsubst (tag, args, /*complain=*/1, NULL_TREE);
5020 if (TREE_CODE (newtag) != ENUMERAL_TYPE)
5021 {
5022 if (TYPE_LANG_SPECIFIC (tag) && CLASSTYPE_IS_TEMPLATE (tag))
5023 /* Unfortunately, lookup_template_class sets
5024 CLASSTYPE_IMPLICIT_INSTANTIATION for a partial
5025 instantiation (i.e., for the type of a member template
5026 class nested within a template class.) This behavior is
5027 required for maybe_process_partial_specialization to work
5028 correctly, but is not accurate in this case; the TAG is not
5029 an instantiation of anything. (The corresponding
5030 TEMPLATE_DECL is an instantiation, but the TYPE is not.) */
5031 CLASSTYPE_USE_TEMPLATE (newtag) = 0;
5032
5033 /* Now, we call pushtag to put this NEWTAG into the scope of
5034 TYPE. We first set up the IDENTIFIER_TYPE_VALUE to avoid
5035 pushtag calling push_template_decl. We don't have to do
5036 this for enums because it will already have been done in
5037 tsubst_enum. */
5038 if (name)
5039 SET_IDENTIFIER_TYPE_VALUE (name, newtag);
5040 pushtag (name, newtag, /*globalize=*/0);
5041 }
5042 }
5043
5044 /* Don't replace enum constants here. */
5045 for (t = TYPE_FIELDS (pattern); t; t = TREE_CHAIN (t))
5046 if (TREE_CODE (t) != CONST_DECL)
5047 {
5048 tree r;
5049
5050 /* The the file and line for this declaration, to assist in
5051 error message reporting. Since we called push_tinst_level
5052 above, we don't need to restore these. */
5053 lineno = DECL_SOURCE_LINE (t);
5054 input_filename = DECL_SOURCE_FILE (t);
5055
5056 r = tsubst (t, args, /*complain=*/1, NULL_TREE);
5057 if (TREE_CODE (r) == VAR_DECL)
5058 {
5059 tree init;
5060
5061 if (DECL_DEFINED_IN_CLASS_P (r))
5062 init = tsubst_expr (DECL_INITIAL (t), args,
5063 /*complain=*/1, NULL_TREE);
5064 else
5065 init = NULL_TREE;
5066
5067 finish_static_data_member_decl (r, init,
5068 /*asmspec_tree=*/NULL_TREE,
5069 /*flags=*/0);
5070
5071 if (DECL_DEFINED_IN_CLASS_P (r))
5072 check_static_variable_definition (r, TREE_TYPE (r));
5073 }
5074
5075 /* R will have a TREE_CHAIN if and only if it has already been
5076 processed by finish_member_declaration. This can happen
5077 if, for example, it is a TYPE_DECL for a class-scoped
5078 ENUMERAL_TYPE; such a thing will already have been added to
5079 the field list by tsubst_enum above. */
5080 if (!TREE_CHAIN (r))
5081 {
5082 set_current_access_from_decl (r);
5083 finish_member_declaration (r);
5084 }
5085 }
5086
5087 /* Set up the list (TYPE_METHODS) and vector (CLASSTYPE_METHOD_VEC)
5088 for this instantiation. */
5089 for (t = TYPE_METHODS (pattern); t; t = TREE_CHAIN (t))
5090 {
5091 tree r = tsubst (t, args, /*complain=*/1, NULL_TREE);
5092 set_current_access_from_decl (r);
5093 finish_member_declaration (r);
5094 }
5095
5096 /* Construct the DECL_FRIENDLIST for the new class type. */
5097 typedecl = TYPE_MAIN_DECL (type);
5098 for (t = DECL_FRIENDLIST (TYPE_MAIN_DECL (pattern));
5099 t != NULL_TREE;
5100 t = TREE_CHAIN (t))
5101 {
5102 tree friends;
5103
5104 for (friends = TREE_VALUE (t);
5105 friends != NULL_TREE;
5106 friends = TREE_CHAIN (friends))
5107 if (TREE_PURPOSE (friends) == error_mark_node)
5108 add_friend (type,
5109 tsubst_friend_function (TREE_VALUE (friends),
5110 args));
5111 else
5112 my_friendly_abort (20000216);
5113 }
5114
5115 for (t = CLASSTYPE_FRIEND_CLASSES (pattern);
5116 t != NULL_TREE;
5117 t = TREE_CHAIN (t))
5118 {
5119 tree friend_type = TREE_VALUE (t);
5120 tree new_friend_type;
5121
5122 if (TREE_CODE (friend_type) == TEMPLATE_DECL)
5123 new_friend_type = tsubst_friend_class (friend_type, args);
5124 else if (uses_template_parms (friend_type))
5125 new_friend_type = tsubst (friend_type, args, /*complain=*/1,
5126 NULL_TREE);
5127 else
5128 {
5129 tree ns = decl_namespace_context (TYPE_MAIN_DECL (friend_type));
5130
5131 /* The call to xref_tag_from_type does injection for friend
5132 classes. */
5133 push_nested_namespace (ns);
5134 new_friend_type =
5135 xref_tag_from_type (friend_type, NULL_TREE, 1);
5136 pop_nested_namespace (ns);
5137 }
5138
5139 if (TREE_CODE (friend_type) == TEMPLATE_DECL)
5140 /* Trick make_friend_class into realizing that the friend
5141 we're adding is a template, not an ordinary class. It's
5142 important that we use make_friend_class since it will
5143 perform some error-checking and output cross-reference
5144 information. */
5145 ++processing_template_decl;
5146
5147 make_friend_class (type, new_friend_type);
5148
5149 if (TREE_CODE (friend_type) == TEMPLATE_DECL)
5150 --processing_template_decl;
5151 }
5152
5153 for (t = TYPE_FIELDS (type); t; t = TREE_CHAIN (t))
5154 if (TREE_CODE (t) == FIELD_DECL)
5155 {
5156 TREE_TYPE (t) = complete_type (TREE_TYPE (t));
5157 require_complete_type (t);
5158 }
5159
5160 /* Set the file and line number information to whatever is given for
5161 the class itself. This puts error messages involving generated
5162 implicit functions at a predictable point, and the same point
5163 that would be used for non-template classes. */
5164 lineno = DECL_SOURCE_LINE (typedecl);
5165 input_filename = DECL_SOURCE_FILE (typedecl);
5166
5167 unreverse_member_declarations (type);
5168 finish_struct_1 (type);
5169 CLASSTYPE_GOT_SEMICOLON (type) = 1;
5170
5171 /* Clear this now so repo_template_used is happy. */
5172 TYPE_BEING_DEFINED (type) = 0;
5173 repo_template_used (type);
5174
5175 /* Now that the class is complete, instantiate default arguments for
5176 any member functions. We don't do this earlier because the
5177 default arguments may reference members of the class. */
5178 if (!PRIMARY_TEMPLATE_P (template))
5179 for (t = TYPE_METHODS (type); t; t = TREE_CHAIN (t))
5180 if (TREE_CODE (t) == FUNCTION_DECL
5181 /* Implicitly generated member functions will not have tmplate
5182 information; they are not instantiations, but instead are
5183 created "fresh" for each instantiation. */
5184 && DECL_TEMPLATE_INFO (t))
5185 tsubst_default_arguments (t);
5186
5187 popclass ();
5188 pop_from_top_level ();
5189 pop_tinst_level ();
5190
5191 return type;
5192 }
5193
5194 static int
5195 list_eq (t1, t2)
5196 tree t1, t2;
5197 {
5198 if (t1 == NULL_TREE)
5199 return t2 == NULL_TREE;
5200 if (t2 == NULL_TREE)
5201 return 0;
5202 /* Don't care if one declares its arg const and the other doesn't -- the
5203 main variant of the arg type is all that matters. */
5204 if (TYPE_MAIN_VARIANT (TREE_VALUE (t1))
5205 != TYPE_MAIN_VARIANT (TREE_VALUE (t2)))
5206 return 0;
5207 return list_eq (TREE_CHAIN (t1), TREE_CHAIN (t2));
5208 }
5209
5210 /* If arg is a non-type template parameter that does not depend on template
5211 arguments, fold it like we weren't in the body of a template. */
5212
5213 static tree
5214 maybe_fold_nontype_arg (arg)
5215 tree arg;
5216 {
5217 /* If we're not in a template, ARG is already as simple as it's going to
5218 get, and trying to reprocess the trees will break. */
5219 if (! processing_template_decl)
5220 return arg;
5221
5222 if (!TYPE_P (arg) && !uses_template_parms (arg))
5223 {
5224 /* Sometimes, one of the args was an expression involving a
5225 template constant parameter, like N - 1. Now that we've
5226 tsubst'd, we might have something like 2 - 1. This will
5227 confuse lookup_template_class, so we do constant folding
5228 here. We have to unset processing_template_decl, to
5229 fool build_expr_from_tree() into building an actual
5230 tree. */
5231
5232 int saved_processing_template_decl = processing_template_decl;
5233 processing_template_decl = 0;
5234 arg = fold (build_expr_from_tree (arg));
5235 processing_template_decl = saved_processing_template_decl;
5236 }
5237 return arg;
5238 }
5239
5240 /* Substitute ARGS into the vector of template arguments T. */
5241
5242 static tree
5243 tsubst_template_arg_vector (t, args, complain)
5244 tree t;
5245 tree args;
5246 int complain;
5247 {
5248 int len = TREE_VEC_LENGTH (t), need_new = 0, i;
5249 tree *elts = (tree *) alloca (len * sizeof (tree));
5250
5251 bzero ((char *) elts, len * sizeof (tree));
5252
5253 for (i = 0; i < len; i++)
5254 {
5255 if (TREE_VEC_ELT (t, i) != NULL_TREE
5256 && TREE_CODE (TREE_VEC_ELT (t, i)) == TREE_VEC)
5257 elts[i] = tsubst_template_arg_vector (TREE_VEC_ELT (t, i),
5258 args, complain);
5259 else
5260 elts[i] = maybe_fold_nontype_arg
5261 (tsubst_expr (TREE_VEC_ELT (t, i), args, complain,
5262 NULL_TREE));
5263
5264 if (elts[i] != TREE_VEC_ELT (t, i))
5265 need_new = 1;
5266 }
5267
5268 if (!need_new)
5269 return t;
5270
5271 t = make_tree_vec (len);
5272 for (i = 0; i < len; i++)
5273 TREE_VEC_ELT (t, i) = elts[i];
5274
5275 return t;
5276 }
5277
5278 /* Return the result of substituting ARGS into the template parameters
5279 given by PARMS. If there are m levels of ARGS and m + n levels of
5280 PARMS, then the result will contain n levels of PARMS. For
5281 example, if PARMS is `template <class T> template <class U>
5282 template <T*, U, class V>' and ARGS is {{int}, {double}} then the
5283 result will be `template <int*, double, class V>'. */
5284
5285 static tree
5286 tsubst_template_parms (parms, args, complain)
5287 tree parms;
5288 tree args;
5289 int complain;
5290 {
5291 tree r = NULL_TREE;
5292 tree* new_parms;
5293
5294 for (new_parms = &r;
5295 TMPL_PARMS_DEPTH (parms) > TMPL_ARGS_DEPTH (args);
5296 new_parms = &(TREE_CHAIN (*new_parms)),
5297 parms = TREE_CHAIN (parms))
5298 {
5299 tree new_vec =
5300 make_tree_vec (TREE_VEC_LENGTH (TREE_VALUE (parms)));
5301 int i;
5302
5303 for (i = 0; i < TREE_VEC_LENGTH (new_vec); ++i)
5304 {
5305 tree default_value =
5306 TREE_PURPOSE (TREE_VEC_ELT (TREE_VALUE (parms), i));
5307 tree parm_decl =
5308 TREE_VALUE (TREE_VEC_ELT (TREE_VALUE (parms), i));
5309
5310 TREE_VEC_ELT (new_vec, i)
5311 = build_tree_list (tsubst (default_value, args, complain,
5312 NULL_TREE),
5313 tsubst (parm_decl, args, complain,
5314 NULL_TREE));
5315 }
5316
5317 *new_parms =
5318 tree_cons (build_int_2 (0, (TMPL_PARMS_DEPTH (parms)
5319 - TMPL_ARGS_DEPTH (args))),
5320 new_vec, NULL_TREE);
5321 }
5322
5323 return r;
5324 }
5325
5326 /* Substitute the ARGS into the indicated aggregate (or enumeration)
5327 type T. If T is not an aggregate or enumeration type, it is
5328 handled as if by tsubst. IN_DECL is as for tsubst. If
5329 ENTERING_SCOPE is non-zero, T is the context for a template which
5330 we are presently tsubst'ing. Return the subsituted value. */
5331
5332 static tree
5333 tsubst_aggr_type (t, args, complain, in_decl, entering_scope)
5334 tree t;
5335 tree args;
5336 int complain;
5337 tree in_decl;
5338 int entering_scope;
5339 {
5340 if (t == NULL_TREE)
5341 return NULL_TREE;
5342
5343 switch (TREE_CODE (t))
5344 {
5345 case RECORD_TYPE:
5346 if (TYPE_PTRMEMFUNC_P (t))
5347 {
5348 tree r = build_ptrmemfunc_type
5349 (tsubst (TYPE_PTRMEMFUNC_FN_TYPE (t), args, complain, in_decl));
5350 return cp_build_qualified_type_real (r, TYPE_QUALS (t),
5351 complain);
5352 }
5353
5354 /* else fall through */
5355 case ENUMERAL_TYPE:
5356 case UNION_TYPE:
5357 if (TYPE_TEMPLATE_INFO (t))
5358 {
5359 tree argvec;
5360 tree context;
5361 tree r;
5362
5363 /* First, determine the context for the type we are looking
5364 up. */
5365 if (TYPE_CONTEXT (t) != NULL_TREE)
5366 context = tsubst_aggr_type (TYPE_CONTEXT (t), args,
5367 complain,
5368 in_decl, /*entering_scope=*/1);
5369 else
5370 context = NULL_TREE;
5371
5372 /* Then, figure out what arguments are appropriate for the
5373 type we are trying to find. For example, given:
5374
5375 template <class T> struct S;
5376 template <class T, class U> void f(T, U) { S<U> su; }
5377
5378 and supposing that we are instantiating f<int, double>,
5379 then our ARGS will be {int, double}, but, when looking up
5380 S we only want {double}. */
5381 argvec = tsubst_template_arg_vector (TYPE_TI_ARGS (t), args,
5382 complain);
5383
5384 r = lookup_template_class (t, argvec, in_decl, context,
5385 entering_scope);
5386
5387 return cp_build_qualified_type_real (r, TYPE_QUALS (t),
5388 complain);
5389 }
5390 else
5391 /* This is not a template type, so there's nothing to do. */
5392 return t;
5393
5394 default:
5395 return tsubst (t, args, complain, in_decl);
5396 }
5397 }
5398
5399 /* Substitute into the default argument ARG (a default argument for
5400 FN), which has the indicated TYPE. */
5401
5402 tree
5403 tsubst_default_argument (fn, type, arg)
5404 tree fn;
5405 tree type;
5406 tree arg;
5407 {
5408 /* This default argument came from a template. Instantiate the
5409 default argument here, not in tsubst. In the case of
5410 something like:
5411
5412 template <class T>
5413 struct S {
5414 static T t();
5415 void f(T = t());
5416 };
5417
5418 we must be careful to do name lookup in the scope of S<T>,
5419 rather than in the current class. */
5420 if (DECL_CLASS_SCOPE_P (fn))
5421 pushclass (DECL_CONTEXT (fn), 2);
5422
5423 arg = tsubst_expr (arg, DECL_TI_ARGS (fn), /*complain=*/1, NULL_TREE);
5424
5425 if (DECL_CLASS_SCOPE_P (fn))
5426 popclass ();
5427
5428 /* Make sure the default argument is reasonable. */
5429 arg = check_default_argument (type, arg);
5430
5431 return arg;
5432 }
5433
5434 /* Substitute into all the default arguments for FN. */
5435
5436 static void
5437 tsubst_default_arguments (fn)
5438 tree fn;
5439 {
5440 tree arg;
5441 tree tmpl_args;
5442
5443 tmpl_args = DECL_TI_ARGS (fn);
5444
5445 /* If this function is not yet instantiated, we certainly don't need
5446 its default arguments. */
5447 if (uses_template_parms (tmpl_args))
5448 return;
5449
5450 for (arg = TYPE_ARG_TYPES (TREE_TYPE (fn));
5451 arg;
5452 arg = TREE_CHAIN (arg))
5453 if (TREE_PURPOSE (arg))
5454 TREE_PURPOSE (arg) = tsubst_default_argument (fn,
5455 TREE_VALUE (arg),
5456 TREE_PURPOSE (arg));
5457 }
5458
5459 /* Substitute the ARGS into the T, which is a _DECL. TYPE is the
5460 (already computed) substitution of ARGS into TREE_TYPE (T), if
5461 appropriate. Return the result of the substitution. IN_DECL is as
5462 for tsubst. */
5463
5464 static tree
5465 tsubst_decl (t, args, type, in_decl)
5466 tree t;
5467 tree args;
5468 tree type;
5469 tree in_decl;
5470 {
5471 int saved_lineno;
5472 const char *saved_filename;
5473 tree r = NULL_TREE;
5474
5475 /* Set the filename and linenumber to improve error-reporting. */
5476 saved_lineno = lineno;
5477 saved_filename = input_filename;
5478 lineno = DECL_SOURCE_LINE (t);
5479 input_filename = DECL_SOURCE_FILE (t);
5480
5481 switch (TREE_CODE (t))
5482 {
5483 case TEMPLATE_DECL:
5484 {
5485 /* We can get here when processing a member template function
5486 of a template class. */
5487 tree decl = DECL_TEMPLATE_RESULT (t);
5488 tree spec;
5489 int is_template_template_parm = DECL_TEMPLATE_TEMPLATE_PARM_P (t);
5490
5491 if (!is_template_template_parm)
5492 {
5493 /* We might already have an instance of this template.
5494 The ARGS are for the surrounding class type, so the
5495 full args contain the tsubst'd args for the context,
5496 plus the innermost args from the template decl. */
5497 tree tmpl_args = DECL_CLASS_TEMPLATE_P (t)
5498 ? CLASSTYPE_TI_ARGS (TREE_TYPE (t))
5499 : DECL_TI_ARGS (DECL_TEMPLATE_RESULT (t));
5500 tree full_args;
5501
5502 full_args = tsubst_template_arg_vector (tmpl_args, args,
5503 /*complain=*/1);
5504
5505 /* tsubst_template_arg_vector doesn't copy the vector if
5506 nothing changed. But, *something* should have
5507 changed. */
5508 my_friendly_assert (full_args != tmpl_args, 0);
5509
5510 spec = retrieve_specialization (t, full_args);
5511 if (spec != NULL_TREE)
5512 {
5513 r = spec;
5514 break;
5515 }
5516 }
5517
5518 /* Make a new template decl. It will be similar to the
5519 original, but will record the current template arguments.
5520 We also create a new function declaration, which is just
5521 like the old one, but points to this new template, rather
5522 than the old one. */
5523 r = copy_decl (t);
5524 my_friendly_assert (DECL_LANG_SPECIFIC (r) != 0, 0);
5525 TREE_CHAIN (r) = NULL_TREE;
5526
5527 if (is_template_template_parm)
5528 {
5529 tree new_decl = tsubst (decl, args, /*complain=*/1, in_decl);
5530 DECL_TEMPLATE_RESULT (r) = new_decl;
5531 TREE_TYPE (r) = TREE_TYPE (new_decl);
5532 break;
5533 }
5534
5535 DECL_CONTEXT (r)
5536 = tsubst_aggr_type (DECL_CONTEXT (t), args,
5537 /*complain=*/1, in_decl,
5538 /*entering_scope=*/1);
5539 DECL_VIRTUAL_CONTEXT (r)
5540 = tsubst_aggr_type (DECL_VIRTUAL_CONTEXT (t), args,
5541 /*complain=*/1, in_decl,
5542 /*entering_scope=*/1);
5543 DECL_TEMPLATE_INFO (r) = build_tree_list (t, args);
5544
5545 if (TREE_CODE (decl) == TYPE_DECL)
5546 {
5547 tree new_type = tsubst (TREE_TYPE (t), args,
5548 /*complain=*/1, in_decl);
5549 TREE_TYPE (r) = new_type;
5550 CLASSTYPE_TI_TEMPLATE (new_type) = r;
5551 DECL_TEMPLATE_RESULT (r) = TYPE_MAIN_DECL (new_type);
5552 DECL_TI_ARGS (r) = CLASSTYPE_TI_ARGS (new_type);
5553 }
5554 else
5555 {
5556 tree new_decl = tsubst (decl, args, /*complain=*/1, in_decl);
5557
5558 DECL_TEMPLATE_RESULT (r) = new_decl;
5559 DECL_TI_TEMPLATE (new_decl) = r;
5560 TREE_TYPE (r) = TREE_TYPE (new_decl);
5561 DECL_TI_ARGS (r) = DECL_TI_ARGS (new_decl);
5562 }
5563
5564 SET_DECL_IMPLICIT_INSTANTIATION (r);
5565 DECL_TEMPLATE_INSTANTIATIONS (r) = NULL_TREE;
5566 DECL_TEMPLATE_SPECIALIZATIONS (r) = NULL_TREE;
5567
5568 /* The template parameters for this new template are all the
5569 template parameters for the old template, except the
5570 outermost level of parameters. */
5571 DECL_TEMPLATE_PARMS (r)
5572 = tsubst_template_parms (DECL_TEMPLATE_PARMS (t), args,
5573 /*complain=*/1);
5574
5575 if (PRIMARY_TEMPLATE_P (t))
5576 DECL_PRIMARY_TEMPLATE (r) = r;
5577
5578 /* We don't partially instantiate partial specializations. */
5579 if (TREE_CODE (decl) == TYPE_DECL)
5580 break;
5581
5582 /* Record this partial instantiation. */
5583 register_specialization (r, t,
5584 DECL_TI_ARGS (DECL_TEMPLATE_RESULT (r)));
5585
5586 }
5587 break;
5588
5589 case FUNCTION_DECL:
5590 {
5591 tree ctx;
5592 tree argvec = NULL_TREE;
5593 tree *friends;
5594 tree gen_tmpl;
5595 int member;
5596 int args_depth;
5597 int parms_depth;
5598
5599 /* Nobody should be tsubst'ing into non-template functions. */
5600 my_friendly_assert (DECL_TEMPLATE_INFO (t) != NULL_TREE, 0);
5601
5602 if (TREE_CODE (DECL_TI_TEMPLATE (t)) == TEMPLATE_DECL)
5603 {
5604 tree spec;
5605
5606 /* Calculate the most general template of which R is a
5607 specialization, and the complete set of arguments used to
5608 specialize R. */
5609 gen_tmpl = most_general_template (DECL_TI_TEMPLATE (t));
5610 argvec
5611 = tsubst_template_arg_vector (DECL_TI_ARGS
5612 (DECL_TEMPLATE_RESULT (gen_tmpl)),
5613 args, /*complain=*/1);
5614
5615 /* Check to see if we already have this specialization. */
5616 spec = retrieve_specialization (gen_tmpl, argvec);
5617
5618 if (spec)
5619 {
5620 r = spec;
5621 break;
5622 }
5623
5624 /* We can see more levels of arguments than parameters if
5625 there was a specialization of a member template, like
5626 this:
5627
5628 template <class T> struct S { template <class U> void f(); }
5629 template <> template <class U> void S<int>::f(U);
5630
5631 Here, we'll be subtituting into the specialization,
5632 because that's where we can find the code we actually
5633 want to generate, but we'll have enough arguments for
5634 the most general template.
5635
5636 We also deal with the peculiar case:
5637
5638 template <class T> struct S {
5639 template <class U> friend void f();
5640 };
5641 template <class U> void f() {}
5642 template S<int>;
5643 template void f<double>();
5644
5645 Here, the ARGS for the instantiation of will be {int,
5646 double}. But, we only need as many ARGS as there are
5647 levels of template parameters in CODE_PATTERN. We are
5648 careful not to get fooled into reducing the ARGS in
5649 situations like:
5650
5651 template <class T> struct S { template <class U> void f(U); }
5652 template <class T> template <> void S<T>::f(int) {}
5653
5654 which we can spot because the pattern will be a
5655 specialization in this case. */
5656 args_depth = TMPL_ARGS_DEPTH (args);
5657 parms_depth =
5658 TMPL_PARMS_DEPTH (DECL_TEMPLATE_PARMS (DECL_TI_TEMPLATE (t)));
5659 if (args_depth > parms_depth
5660 && !DECL_TEMPLATE_SPECIALIZATION (t))
5661 args = get_innermost_template_args (args, parms_depth);
5662 }
5663 else
5664 {
5665 /* This special case arises when we have something like this:
5666
5667 template <class T> struct S {
5668 friend void f<int>(int, double);
5669 };
5670
5671 Here, the DECL_TI_TEMPLATE for the friend declaration
5672 will be a LOOKUP_EXPR or an IDENTIFIER_NODE. We are
5673 being called from tsubst_friend_function, and we want
5674 only to create a new decl (R) with appropriate types so
5675 that we can call determine_specialization. */
5676 my_friendly_assert ((TREE_CODE (DECL_TI_TEMPLATE (t))
5677 == LOOKUP_EXPR)
5678 || (TREE_CODE (DECL_TI_TEMPLATE (t))
5679 == IDENTIFIER_NODE), 0);
5680 gen_tmpl = NULL_TREE;
5681 }
5682
5683 if (DECL_CLASS_SCOPE_P (t))
5684 {
5685 if (DECL_NAME (t) == constructor_name (DECL_CONTEXT (t)))
5686 member = 2;
5687 else
5688 member = 1;
5689 ctx = tsubst_aggr_type (DECL_CONTEXT (t), args,
5690 /*complain=*/1, t,
5691 /*entering_scope=*/1);
5692 }
5693 else
5694 {
5695 member = 0;
5696 ctx = DECL_CONTEXT (t);
5697 }
5698 type = tsubst (type, args, /*complain=*/1, in_decl);
5699 if (type == error_mark_node)
5700 return error_mark_node;
5701
5702 /* We do NOT check for matching decls pushed separately at this
5703 point, as they may not represent instantiations of this
5704 template, and in any case are considered separate under the
5705 discrete model. Instead, see add_maybe_template. */
5706 r = copy_decl (t);
5707 DECL_USE_TEMPLATE (r) = 0;
5708 TREE_TYPE (r) = type;
5709
5710 DECL_CONTEXT (r) = ctx;
5711 DECL_VIRTUAL_CONTEXT (r)
5712 = tsubst_aggr_type (DECL_VIRTUAL_CONTEXT (t), args,
5713 /*complain=*/1, t,
5714 /*entering_scope=*/1);
5715
5716 if (member && DECL_CONV_FN_P (r))
5717 {
5718 /* Type-conversion operator. Reconstruct the name, in
5719 case it's the name of one of the template's parameters. */
5720 if (flag_new_abi)
5721 DECL_NAME (r) = mangle_conv_op_name_for_type (TREE_TYPE (type));
5722 else
5723 DECL_NAME (r) = build_typename_overload (TREE_TYPE (type));
5724 }
5725
5726 DECL_ARGUMENTS (r) = tsubst (DECL_ARGUMENTS (t), args,
5727 /*complain=*/1, t);
5728 DECL_TEMPLATE_RESULT (r) = NULL_TREE;
5729
5730 TREE_STATIC (r) = 0;
5731 TREE_PUBLIC (r) = TREE_PUBLIC (t);
5732 DECL_EXTERNAL (r) = 1;
5733 DECL_INTERFACE_KNOWN (r) = 0;
5734 DECL_DEFER_OUTPUT (r) = 0;
5735 TREE_CHAIN (r) = NULL_TREE;
5736 DECL_PENDING_INLINE_INFO (r) = 0;
5737 DECL_PENDING_INLINE_P (r) = 0;
5738 DECL_SAVED_TREE (r) = NULL_TREE;
5739 TREE_USED (r) = 0;
5740 if (DECL_CLONED_FUNCTION (r))
5741 {
5742 DECL_CLONED_FUNCTION (r) = tsubst (DECL_CLONED_FUNCTION (t),
5743 args, /*complain=*/1, t);
5744 TREE_CHAIN (r) = TREE_CHAIN (DECL_CLONED_FUNCTION (r));
5745 TREE_CHAIN (DECL_CLONED_FUNCTION (r)) = r;
5746 }
5747
5748 /* Set up the DECL_TEMPLATE_INFO for R and compute its mangled
5749 name. There's no need to do this in the special friend
5750 case mentioned above where GEN_TMPL is NULL. */
5751 if (gen_tmpl)
5752 {
5753 DECL_TEMPLATE_INFO (r)
5754 = tree_cons (gen_tmpl, argvec, NULL_TREE);
5755 SET_DECL_IMPLICIT_INSTANTIATION (r);
5756 register_specialization (r, gen_tmpl, argvec);
5757
5758 /* Set the mangled name for R. */
5759 if (DECL_DESTRUCTOR_P (t))
5760 {
5761 if (flag_new_abi)
5762 set_mangled_name_for_decl (r);
5763 else
5764 DECL_ASSEMBLER_NAME (r) = build_destructor_name (ctx);
5765 }
5766 else
5767 {
5768 /* Instantiations of template functions must be mangled
5769 specially, in order to conform to 14.5.5.1
5770 [temp.over.link]. */
5771 tree tmpl = DECL_TI_TEMPLATE (t);
5772
5773 /* TMPL will be NULL if this is a specialization of a
5774 member function of a template class. */
5775 if (name_mangling_version < 1
5776 || tmpl == NULL_TREE
5777 || (member && !is_member_template (tmpl)
5778 && !DECL_TEMPLATE_INFO (tmpl)))
5779 set_mangled_name_for_decl (r);
5780 else
5781 set_mangled_name_for_template_decl (r);
5782 }
5783
5784 DECL_RTL (r) = 0;
5785 make_decl_rtl (r, NULL_PTR, 1);
5786
5787 /* Like grokfndecl. If we don't do this, pushdecl will
5788 mess up our TREE_CHAIN because it doesn't find a
5789 previous decl. Sigh. */
5790 if (member
5791 && ! uses_template_parms (r)
5792 && (IDENTIFIER_GLOBAL_VALUE (DECL_ASSEMBLER_NAME (r))
5793 == NULL_TREE))
5794 SET_IDENTIFIER_GLOBAL_VALUE (DECL_ASSEMBLER_NAME (r), r);
5795
5796 /* We're not supposed to instantiate default arguments
5797 until they are called, for a template. But, for a
5798 declaration like:
5799
5800 template <class T> void f ()
5801 { extern void g(int i = T()); }
5802
5803 we should do the substitution when the template is
5804 instantiated. We handle the member function case in
5805 instantiate_class_template since the default arguments
5806 might refer to other members of the class. */
5807 if (!member
5808 && !PRIMARY_TEMPLATE_P (gen_tmpl)
5809 && !uses_template_parms (argvec))
5810 tsubst_default_arguments (r);
5811 }
5812
5813 /* Copy the list of befriending classes. */
5814 for (friends = &DECL_BEFRIENDING_CLASSES (r);
5815 *friends;
5816 friends = &TREE_CHAIN (*friends))
5817 {
5818 *friends = copy_node (*friends);
5819 TREE_VALUE (*friends) = tsubst (TREE_VALUE (*friends),
5820 args, /*complain=*/1,
5821 in_decl);
5822 }
5823
5824 if (DECL_CONSTRUCTOR_P (r) || DECL_DESTRUCTOR_P (r))
5825 {
5826 maybe_retrofit_in_chrg (r);
5827 if (DECL_CONSTRUCTOR_P (r))
5828 grok_ctor_properties (ctx, r);
5829 }
5830 else if (IDENTIFIER_OPNAME_P (DECL_NAME (r)))
5831 grok_op_properties (r, DECL_VIRTUAL_P (r), DECL_FRIEND_P (r));
5832 }
5833 break;
5834
5835 case PARM_DECL:
5836 {
5837 r = copy_node (t);
5838 TREE_TYPE (r) = type;
5839 c_apply_type_quals_to_decl (CP_TYPE_QUALS (type), r);
5840
5841 if (TREE_CODE (DECL_INITIAL (r)) != TEMPLATE_PARM_INDEX)
5842 DECL_INITIAL (r) = TREE_TYPE (r);
5843 else
5844 DECL_INITIAL (r) = tsubst (DECL_INITIAL (r), args,
5845 /*complain=*/1, in_decl);
5846
5847 DECL_CONTEXT (r) = NULL_TREE;
5848 if (PROMOTE_PROTOTYPES
5849 && (TREE_CODE (type) == INTEGER_TYPE
5850 || TREE_CODE (type) == ENUMERAL_TYPE)
5851 && TYPE_PRECISION (type) < TYPE_PRECISION (integer_type_node))
5852 DECL_ARG_TYPE (r) = integer_type_node;
5853 if (TREE_CHAIN (t))
5854 TREE_CHAIN (r) = tsubst (TREE_CHAIN (t), args,
5855 /*complain=*/1, TREE_CHAIN (t));
5856 }
5857 break;
5858
5859 case FIELD_DECL:
5860 {
5861 r = copy_decl (t);
5862 TREE_TYPE (r) = type;
5863 c_apply_type_quals_to_decl (CP_TYPE_QUALS (type), r);
5864
5865 /* We don't have to set DECL_CONTEXT here; it is set by
5866 finish_member_declaration. */
5867 DECL_INITIAL (r) = tsubst_expr (DECL_INITIAL (t), args,
5868 /*complain=*/1, in_decl);
5869 TREE_CHAIN (r) = NULL_TREE;
5870 if (TREE_CODE (type) == VOID_TYPE)
5871 cp_error_at ("instantiation of `%D' as type void", r);
5872 }
5873 break;
5874
5875 case USING_DECL:
5876 {
5877 r = copy_node (t);
5878 DECL_INITIAL (r)
5879 = tsubst_copy (DECL_INITIAL (t), args, /*complain=*/1, in_decl);
5880 TREE_CHAIN (r) = NULL_TREE;
5881 }
5882 break;
5883
5884 case TYPE_DECL:
5885 if (TREE_CODE (type) == TEMPLATE_TEMPLATE_PARM
5886 || t == TYPE_MAIN_DECL (TREE_TYPE (t)))
5887 {
5888 /* If this is the canonical decl, we don't have to mess with
5889 instantiations, and often we can't (for typename, template
5890 type parms and such). Note that TYPE_NAME is not correct for
5891 the above test if we've copied the type for a typedef. */
5892 r = TYPE_NAME (type);
5893 break;
5894 }
5895
5896 /* Fall through. */
5897
5898 case VAR_DECL:
5899 {
5900 tree argvec = NULL_TREE;
5901 tree gen_tmpl = NULL_TREE;
5902 tree spec;
5903 tree tmpl = NULL_TREE;
5904 tree ctx;
5905 int local_p;
5906
5907 /* Assume this is a non-local variable. */
5908 local_p = 0;
5909
5910 if (TYPE_P (CP_DECL_CONTEXT (t)))
5911 ctx = tsubst_aggr_type (DECL_CONTEXT (t), args,
5912 /*complain=*/1,
5913 in_decl, /*entering_scope=*/1);
5914 else
5915 {
5916 /* Subsequent calls to pushdecl will fill this in. */
5917 ctx = NULL_TREE;
5918 if (!DECL_NAMESPACE_SCOPE_P (t))
5919 local_p = 1;
5920 }
5921
5922 /* Check to see if we already have this specialization. */
5923 if (!local_p)
5924 {
5925 tmpl = DECL_TI_TEMPLATE (t);
5926 gen_tmpl = most_general_template (tmpl);
5927 argvec = tsubst (DECL_TI_ARGS (t), args, /*complain=*/1, in_decl);
5928 spec = retrieve_specialization (gen_tmpl, argvec);
5929 }
5930 else
5931 spec = retrieve_local_specialization (t);
5932
5933 if (spec)
5934 {
5935 r = spec;
5936 break;
5937 }
5938
5939 r = copy_decl (t);
5940 TREE_TYPE (r) = type;
5941 c_apply_type_quals_to_decl (CP_TYPE_QUALS (type), r);
5942 DECL_CONTEXT (r) = ctx;
5943
5944 /* Don't try to expand the initializer until someone tries to use
5945 this variable; otherwise we run into circular dependencies. */
5946 DECL_INITIAL (r) = NULL_TREE;
5947 DECL_RTL (r) = 0;
5948 DECL_SIZE (r) = DECL_SIZE_UNIT (r) = 0;
5949
5950 /* For __PRETTY_FUNCTION__ we have to adjust the initializer. */
5951 if (DECL_PRETTY_FUNCTION_P (r))
5952 {
5953 DECL_INITIAL (r) = tsubst (DECL_INITIAL (t),
5954 args,
5955 /*complain=*/1,
5956 NULL_TREE);
5957 TREE_TYPE (r) = TREE_TYPE (DECL_INITIAL (r));
5958 }
5959
5960 /* Even if the original location is out of scope, the newly
5961 substituted one is not. */
5962 if (TREE_CODE (r) == VAR_DECL)
5963 DECL_DEAD_FOR_LOCAL (r) = 0;
5964
5965 if (!local_p)
5966 {
5967 /* A static data member declaration is always marked
5968 external when it is declared in-class, even if an
5969 initializer is present. We mimic the non-template
5970 processing here. */
5971 DECL_EXTERNAL (r) = 1;
5972
5973 register_specialization (r, gen_tmpl, argvec);
5974 DECL_TEMPLATE_INFO (r) = tree_cons (tmpl, argvec, NULL_TREE);
5975 SET_DECL_IMPLICIT_INSTANTIATION (r);
5976 }
5977 else
5978 register_local_specialization (r, t);
5979
5980 TREE_CHAIN (r) = NULL_TREE;
5981 if (TREE_CODE (r) == VAR_DECL && TREE_CODE (type) == VOID_TYPE)
5982 cp_error_at ("instantiation of `%D' as type void", r);
5983 }
5984 break;
5985
5986 default:
5987 my_friendly_abort (0);
5988 }
5989
5990 /* Restore the file and line information. */
5991 lineno = saved_lineno;
5992 input_filename = saved_filename;
5993
5994 return r;
5995 }
5996
5997 /* Substitue into the ARG_TYPES of a function type. */
5998
5999 static tree
6000 tsubst_arg_types (arg_types, args, complain, in_decl)
6001 tree arg_types;
6002 tree args;
6003 int complain;
6004 tree in_decl;
6005 {
6006 tree remaining_arg_types;
6007 tree type;
6008
6009 if (!arg_types || arg_types == void_list_node)
6010 return arg_types;
6011
6012 remaining_arg_types = tsubst_arg_types (TREE_CHAIN (arg_types),
6013 args, complain, in_decl);
6014 if (remaining_arg_types == error_mark_node)
6015 return error_mark_node;
6016
6017 type = tsubst (TREE_VALUE (arg_types), args, complain, in_decl);
6018 if (type == error_mark_node)
6019 return error_mark_node;
6020
6021 /* Do array-to-pointer, function-to-pointer conversion, and ignore
6022 top-level qualifiers as required. */
6023 type = TYPE_MAIN_VARIANT (type_decays_to (type));
6024
6025 /* Note that we do not substitute into default arguments here. The
6026 standard mandates that they be instantiated only when needed,
6027 which is done in build_over_call. */
6028 return hash_tree_cons (TREE_PURPOSE (arg_types), type,
6029 remaining_arg_types);
6030
6031 }
6032
6033 /* Substitute into a FUNCTION_TYPE or METHOD_TYPE. This routine does
6034 *not* handle the exception-specification for FNTYPE, because the
6035 initial substitution of explicitly provided template parameters
6036 during argument deduction forbids substitution into the
6037 exception-specification:
6038
6039 [temp.deduct]
6040
6041 All references in the function type of the function template to the
6042 corresponding template parameters are replaced by the specified tem-
6043 plate argument values. If a substitution in a template parameter or
6044 in the function type of the function template results in an invalid
6045 type, type deduction fails. [Note: The equivalent substitution in
6046 exception specifications is done only when the function is instanti-
6047 ated, at which point a program is ill-formed if the substitution
6048 results in an invalid type.] */
6049
6050 static tree
6051 tsubst_function_type (t, args, complain, in_decl)
6052 tree t;
6053 tree args;
6054 int complain;
6055 tree in_decl;
6056 {
6057 tree return_type;
6058 tree arg_types;
6059 tree fntype;
6060
6061 /* The TYPE_CONTEXT is not used for function/method types. */
6062 my_friendly_assert (TYPE_CONTEXT (t) == NULL_TREE, 0);
6063
6064 /* Substitue the return type. */
6065 return_type = tsubst (TREE_TYPE (t), args, complain, in_decl);
6066 if (return_type == error_mark_node)
6067 return error_mark_node;
6068
6069 /* Substitue the argument types. */
6070 arg_types = tsubst_arg_types (TYPE_ARG_TYPES (t), args,
6071 complain, in_decl);
6072 if (arg_types == error_mark_node)
6073 return error_mark_node;
6074
6075 /* Construct a new type node and return it. */
6076 if (TREE_CODE (t) == FUNCTION_TYPE)
6077 fntype = build_function_type (return_type, arg_types);
6078 else
6079 {
6080 tree r = TREE_TYPE (TREE_VALUE (arg_types));
6081 if (! IS_AGGR_TYPE (r))
6082 {
6083 /* [temp.deduct]
6084
6085 Type deduction may fail for any of the following
6086 reasons:
6087
6088 -- Attempting to create "pointer to member of T" when T
6089 is not a class type. */
6090 if (complain)
6091 cp_error ("creating pointer to member function of non-class type `%T'",
6092 r);
6093 return error_mark_node;
6094 }
6095
6096 fntype = build_cplus_method_type (r, return_type, TREE_CHAIN
6097 (arg_types));
6098 }
6099 fntype = build_qualified_type (fntype, TYPE_QUALS (t));
6100 fntype = build_type_attribute_variant (fntype, TYPE_ATTRIBUTES (t));
6101
6102 return fntype;
6103 }
6104
6105 /* Substitute into the PARMS of a call-declarator. */
6106
6107 static tree
6108 tsubst_call_declarator_parms (parms, args, complain, in_decl)
6109 tree parms;
6110 tree args;
6111 int complain;
6112 tree in_decl;
6113 {
6114 tree new_parms;
6115 tree type;
6116 tree defarg;
6117
6118 if (!parms || parms == void_list_node)
6119 return parms;
6120
6121 new_parms = tsubst_call_declarator_parms (TREE_CHAIN (parms),
6122 args, complain, in_decl);
6123
6124 /* Figure out the type of this parameter. */
6125 type = tsubst (TREE_VALUE (parms), args, complain, in_decl);
6126
6127 /* Figure out the default argument as well. Note that we use
6128 tsubst_expr since the default argument is really an expression. */
6129 defarg = tsubst_expr (TREE_PURPOSE (parms), args, complain, in_decl);
6130
6131 /* Chain this parameter on to the front of those we have already
6132 processed. We don't use hash_tree_cons because that function
6133 doesn't check TREE_PARMLIST. */
6134 new_parms = tree_cons (defarg, type, new_parms);
6135
6136 /* And note that these are parameters. */
6137 TREE_PARMLIST (new_parms) = 1;
6138
6139 return new_parms;
6140 }
6141
6142 /* Take the tree structure T and replace template parameters used
6143 therein with the argument vector ARGS. IN_DECL is an associated
6144 decl for diagnostics. If an error occurs, returns ERROR_MARK_NODE.
6145 An appropriate error message is issued only if COMPLAIN is
6146 non-zero. Note that we must be relatively non-tolerant of
6147 extensions here, in order to preserve conformance; if we allow
6148 substitutions that should not be allowed, we may allow argument
6149 deductions that should not succeed, and therefore report ambiguous
6150 overload situations where there are none. In theory, we could
6151 allow the substitution, but indicate that it should have failed,
6152 and allow our caller to make sure that the right thing happens, but
6153 we don't try to do this yet.
6154
6155 This function is used for dealing with types, decls and the like;
6156 for expressions, use tsubst_expr or tsubst_copy. */
6157
6158 tree
6159 tsubst (t, args, complain, in_decl)
6160 tree t, args;
6161 int complain;
6162 tree in_decl;
6163 {
6164 tree type, r;
6165
6166 if (t == NULL_TREE || t == error_mark_node
6167 || t == integer_type_node
6168 || t == void_type_node
6169 || t == char_type_node
6170 || TREE_CODE (t) == NAMESPACE_DECL)
6171 return t;
6172
6173 if (TREE_CODE (t) == IDENTIFIER_NODE)
6174 type = IDENTIFIER_TYPE_VALUE (t);
6175 else
6176 type = TREE_TYPE (t);
6177 if (type == unknown_type_node)
6178 my_friendly_abort (42);
6179
6180 if (type && TREE_CODE (t) != FUNCTION_DECL
6181 && TREE_CODE (t) != TYPENAME_TYPE
6182 && TREE_CODE (t) != TEMPLATE_DECL
6183 && TREE_CODE (t) != IDENTIFIER_NODE
6184 && TREE_CODE (t) != FUNCTION_TYPE
6185 && TREE_CODE (t) != METHOD_TYPE)
6186 type = tsubst (type, args, complain, in_decl);
6187 if (type == error_mark_node)
6188 return error_mark_node;
6189
6190 if (DECL_P (t))
6191 return tsubst_decl (t, args, type, in_decl);
6192
6193 switch (TREE_CODE (t))
6194 {
6195 case RECORD_TYPE:
6196 case UNION_TYPE:
6197 case ENUMERAL_TYPE:
6198 return tsubst_aggr_type (t, args, complain, in_decl,
6199 /*entering_scope=*/0);
6200
6201 case ERROR_MARK:
6202 case IDENTIFIER_NODE:
6203 case OP_IDENTIFIER:
6204 case VOID_TYPE:
6205 case REAL_TYPE:
6206 case COMPLEX_TYPE:
6207 case BOOLEAN_TYPE:
6208 case INTEGER_CST:
6209 case REAL_CST:
6210 case STRING_CST:
6211 return t;
6212
6213 case INTEGER_TYPE:
6214 if (t == integer_type_node)
6215 return t;
6216
6217 if (TREE_CODE (TYPE_MIN_VALUE (t)) == INTEGER_CST
6218 && TREE_CODE (TYPE_MAX_VALUE (t)) == INTEGER_CST)
6219 return t;
6220
6221 {
6222 tree max, omax = TREE_OPERAND (TYPE_MAX_VALUE (t), 0);
6223
6224 max = tsubst_expr (omax, args, complain, in_decl);
6225 if (max == error_mark_node)
6226 return error_mark_node;
6227
6228 /* See if we can reduce this expression to something simpler. */
6229 max = maybe_fold_nontype_arg (max);
6230 if (!processing_template_decl)
6231 max = decl_constant_value (max);
6232
6233 if (processing_template_decl
6234 /* When providing explicit arguments to a template
6235 function, but leaving some arguments for subsequent
6236 deduction, MAX may be template-dependent even if we're
6237 not PROCESSING_TEMPLATE_DECL. We still need to check for
6238 template parms, though; MAX won't be an INTEGER_CST for
6239 dynamic arrays, either. */
6240 || (TREE_CODE (max) != INTEGER_CST
6241 && uses_template_parms (max)))
6242 {
6243 tree itype = make_node (INTEGER_TYPE);
6244 TYPE_MIN_VALUE (itype) = size_zero_node;
6245 TYPE_MAX_VALUE (itype) = build_min (MINUS_EXPR, sizetype, max,
6246 integer_one_node);
6247 return itype;
6248 }
6249
6250 if (integer_zerop (omax))
6251 {
6252 /* Still allow an explicit array of size zero. */
6253 if (pedantic)
6254 pedwarn ("creating array with size zero");
6255 }
6256 else if (integer_zerop (max)
6257 || (TREE_CODE (max) == INTEGER_CST
6258 && INT_CST_LT (max, integer_zero_node)))
6259 {
6260 /* [temp.deduct]
6261
6262 Type deduction may fail for any of the following
6263 reasons:
6264
6265 Attempting to create an array with a size that is
6266 zero or negative. */
6267 if (complain)
6268 cp_error ("creating array with size zero (`%E')", max);
6269
6270 return error_mark_node;
6271 }
6272
6273 return compute_array_index_type (NULL_TREE, max);
6274 }
6275
6276 case TEMPLATE_TYPE_PARM:
6277 case TEMPLATE_TEMPLATE_PARM:
6278 case TEMPLATE_PARM_INDEX:
6279 {
6280 int idx;
6281 int level;
6282 int levels;
6283
6284 r = NULL_TREE;
6285
6286 if (TREE_CODE (t) == TEMPLATE_TYPE_PARM
6287 || TREE_CODE (t) == TEMPLATE_TEMPLATE_PARM)
6288 {
6289 idx = TEMPLATE_TYPE_IDX (t);
6290 level = TEMPLATE_TYPE_LEVEL (t);
6291 }
6292 else
6293 {
6294 idx = TEMPLATE_PARM_IDX (t);
6295 level = TEMPLATE_PARM_LEVEL (t);
6296 }
6297
6298 if (TREE_VEC_LENGTH (args) > 0)
6299 {
6300 tree arg = NULL_TREE;
6301
6302 levels = TMPL_ARGS_DEPTH (args);
6303 if (level <= levels)
6304 arg = TMPL_ARG (args, level, idx);
6305
6306 if (arg == error_mark_node)
6307 return error_mark_node;
6308 else if (arg != NULL_TREE)
6309 {
6310 if (TREE_CODE (t) == TEMPLATE_TYPE_PARM)
6311 {
6312 my_friendly_assert (TYPE_P (arg), 0);
6313 return cp_build_qualified_type_real
6314 (arg, CP_TYPE_QUALS (arg) | CP_TYPE_QUALS (t),
6315 complain);
6316 }
6317 else if (TREE_CODE (t) == TEMPLATE_TEMPLATE_PARM)
6318 {
6319 if (TEMPLATE_TEMPLATE_PARM_TEMPLATE_INFO (t))
6320 {
6321 /* We are processing a type constructed from
6322 a template template parameter */
6323 tree argvec = tsubst (TYPE_TI_ARGS (t),
6324 args, complain, in_decl);
6325 if (argvec == error_mark_node)
6326 return error_mark_node;
6327
6328 /* We can get a TEMPLATE_TEMPLATE_PARM here when
6329 we are resolving nested-types in the signature of
6330 a member function templates.
6331 Otherwise ARG is a TEMPLATE_DECL and is the real
6332 template to be instantiated. */
6333 if (TREE_CODE (arg) == TEMPLATE_TEMPLATE_PARM)
6334 arg = TYPE_NAME (arg);
6335
6336 r = lookup_template_class (arg,
6337 argvec, in_decl,
6338 DECL_CONTEXT (arg),
6339 /*entering_scope=*/0);
6340 return cp_build_qualified_type_real (r,
6341 TYPE_QUALS (t),
6342 complain);
6343 }
6344 else
6345 /* We are processing a template argument list. */
6346 return arg;
6347 }
6348 else
6349 return arg;
6350 }
6351 }
6352 else
6353 my_friendly_abort (981018);
6354
6355 if (level == 1)
6356 /* This can happen during the attempted tsubst'ing in
6357 unify. This means that we don't yet have any information
6358 about the template parameter in question. */
6359 return t;
6360
6361 /* If we get here, we must have been looking at a parm for a
6362 more deeply nested template. Make a new version of this
6363 template parameter, but with a lower level. */
6364 switch (TREE_CODE (t))
6365 {
6366 case TEMPLATE_TYPE_PARM:
6367 case TEMPLATE_TEMPLATE_PARM:
6368 if (CP_TYPE_QUALS (t))
6369 {
6370 r = tsubst (TYPE_MAIN_VARIANT (t), args, complain, in_decl);
6371 r = cp_build_qualified_type_real (r, CP_TYPE_QUALS (t),
6372 complain);
6373 }
6374 else
6375 {
6376 r = copy_node (t);
6377 TEMPLATE_TYPE_PARM_INDEX (r)
6378 = reduce_template_parm_level (TEMPLATE_TYPE_PARM_INDEX (t),
6379 r, levels);
6380 TYPE_STUB_DECL (r) = TYPE_NAME (r) = TEMPLATE_TYPE_DECL (r);
6381 TYPE_MAIN_VARIANT (r) = r;
6382 TYPE_POINTER_TO (r) = NULL_TREE;
6383 TYPE_REFERENCE_TO (r) = NULL_TREE;
6384
6385 if (TREE_CODE (t) == TEMPLATE_TEMPLATE_PARM
6386 && TEMPLATE_TEMPLATE_PARM_TEMPLATE_INFO (t))
6387 {
6388 tree argvec = tsubst (TYPE_TI_ARGS (t), args,
6389 complain, in_decl);
6390 if (argvec == error_mark_node)
6391 return error_mark_node;
6392
6393 TEMPLATE_TEMPLATE_PARM_TEMPLATE_INFO (r)
6394 = tree_cons (TYPE_TI_TEMPLATE (t), argvec, NULL_TREE);
6395 }
6396 }
6397 break;
6398
6399 case TEMPLATE_PARM_INDEX:
6400 r = reduce_template_parm_level (t, type, levels);
6401 break;
6402
6403 default:
6404 my_friendly_abort (0);
6405 }
6406
6407 return r;
6408 }
6409
6410 case TREE_LIST:
6411 {
6412 tree purpose, value, chain, result;
6413
6414 if (t == void_list_node)
6415 return t;
6416
6417 purpose = TREE_PURPOSE (t);
6418 if (purpose)
6419 {
6420 purpose = tsubst (purpose, args, complain, in_decl);
6421 if (purpose == error_mark_node)
6422 return error_mark_node;
6423 }
6424 value = TREE_VALUE (t);
6425 if (value)
6426 {
6427 value = tsubst (value, args, complain, in_decl);
6428 if (value == error_mark_node)
6429 return error_mark_node;
6430 }
6431 chain = TREE_CHAIN (t);
6432 if (chain && chain != void_type_node)
6433 {
6434 chain = tsubst (chain, args, complain, in_decl);
6435 if (chain == error_mark_node)
6436 return error_mark_node;
6437 }
6438 if (purpose == TREE_PURPOSE (t)
6439 && value == TREE_VALUE (t)
6440 && chain == TREE_CHAIN (t))
6441 return t;
6442 result = hash_tree_cons (purpose, value, chain);
6443 TREE_PARMLIST (result) = TREE_PARMLIST (t);
6444 return result;
6445 }
6446 case TREE_VEC:
6447 if (type != NULL_TREE)
6448 {
6449 /* A binfo node. We always need to make a copy, of the node
6450 itself and of its BINFO_BASETYPES. */
6451
6452 t = copy_node (t);
6453
6454 /* Make sure type isn't a typedef copy. */
6455 type = BINFO_TYPE (TYPE_BINFO (type));
6456
6457 TREE_TYPE (t) = complete_type (type);
6458 if (IS_AGGR_TYPE (type))
6459 {
6460 BINFO_VTABLE (t) = TYPE_BINFO_VTABLE (type);
6461 BINFO_VIRTUALS (t) = TYPE_BINFO_VIRTUALS (type);
6462 if (TYPE_BINFO_BASETYPES (type) != NULL_TREE)
6463 BINFO_BASETYPES (t) = copy_node (TYPE_BINFO_BASETYPES (type));
6464 }
6465 return t;
6466 }
6467
6468 /* Otherwise, a vector of template arguments. */
6469 return tsubst_template_arg_vector (t, args, complain);
6470
6471 case POINTER_TYPE:
6472 case REFERENCE_TYPE:
6473 {
6474 enum tree_code code;
6475
6476 if (type == TREE_TYPE (t))
6477 return t;
6478
6479 code = TREE_CODE (t);
6480
6481
6482 /* [temp.deduct]
6483
6484 Type deduction may fail for any of the following
6485 reasons:
6486
6487 -- Attempting to create a pointer to reference type.
6488 -- Attempting to create a reference to a reference type or
6489 a reference to void. */
6490 if (TREE_CODE (type) == REFERENCE_TYPE
6491 || (code == REFERENCE_TYPE && TREE_CODE (type) == VOID_TYPE))
6492 {
6493 static int last_line = 0;
6494 static const char* last_file = 0;
6495
6496 /* We keep track of the last time we issued this error
6497 message to avoid spewing a ton of messages during a
6498 single bad template instantiation. */
6499 if (complain && (last_line != lineno ||
6500 last_file != input_filename))
6501 {
6502 if (TREE_CODE (type) == VOID_TYPE)
6503 cp_error ("forming reference to void");
6504 else
6505 cp_error ("forming %s to reference type `%T'",
6506 (code == POINTER_TYPE) ? "pointer" : "reference",
6507 type);
6508 last_line = lineno;
6509 last_file = input_filename;
6510 }
6511
6512 return error_mark_node;
6513 }
6514 else if (code == POINTER_TYPE)
6515 r = build_pointer_type (type);
6516 else
6517 r = build_reference_type (type);
6518 r = cp_build_qualified_type_real (r, TYPE_QUALS (t), complain);
6519
6520 if (r != error_mark_node)
6521 /* Will this ever be needed for TYPE_..._TO values? */
6522 layout_type (r);
6523
6524 return r;
6525 }
6526 case OFFSET_TYPE:
6527 {
6528 r = tsubst (TYPE_OFFSET_BASETYPE (t), args, complain, in_decl);
6529 if (r == error_mark_node || !IS_AGGR_TYPE (r))
6530 {
6531 /* [temp.deduct]
6532
6533 Type deduction may fail for any of the following
6534 reasons:
6535
6536 -- Attempting to create "pointer to member of T" when T
6537 is not a class type. */
6538 if (complain)
6539 cp_error ("creating pointer to member of non-class type `%T'",
6540 r);
6541 return error_mark_node;
6542 }
6543 return build_offset_type (r, type);
6544 }
6545 case FUNCTION_TYPE:
6546 case METHOD_TYPE:
6547 {
6548 tree fntype;
6549 tree raises;
6550
6551 fntype = tsubst_function_type (t, args, complain, in_decl);
6552 if (fntype == error_mark_node)
6553 return error_mark_node;
6554
6555 /* Substitue the exception specification. */
6556 raises = TYPE_RAISES_EXCEPTIONS (t);
6557 if (raises)
6558 {
6559 tree list = NULL_TREE;
6560
6561 if (! TREE_VALUE (raises))
6562 list = raises;
6563 else
6564 for (; raises != NULL_TREE; raises = TREE_CHAIN (raises))
6565 {
6566 tree spec = TREE_VALUE (raises);
6567
6568 spec = tsubst (spec, args, complain, in_decl);
6569 if (spec == error_mark_node)
6570 return spec;
6571 list = add_exception_specifier (list, spec, complain);
6572 }
6573 fntype = build_exception_variant (fntype, list);
6574 }
6575 return fntype;
6576 }
6577 case ARRAY_TYPE:
6578 {
6579 tree domain = tsubst (TYPE_DOMAIN (t), args, complain, in_decl);
6580 if (domain == error_mark_node)
6581 return error_mark_node;
6582
6583 /* As an optimization, we avoid regenerating the array type if
6584 it will obviously be the same as T. */
6585 if (type == TREE_TYPE (t) && domain == TYPE_DOMAIN (t))
6586 return t;
6587
6588 /* These checks should match the ones in grokdeclarator.
6589
6590 [temp.deduct]
6591
6592 The deduction may fail for any of the following reasons:
6593
6594 -- Attempting to create an array with an element type that
6595 is void, a function type, or a reference type. */
6596 if (TREE_CODE (type) == VOID_TYPE
6597 || TREE_CODE (type) == FUNCTION_TYPE
6598 || TREE_CODE (type) == REFERENCE_TYPE)
6599 {
6600 if (complain)
6601 cp_error ("creating array of `%T'", type);
6602 return error_mark_node;
6603 }
6604
6605 r = build_cplus_array_type (type, domain);
6606 return r;
6607 }
6608
6609 case PLUS_EXPR:
6610 case MINUS_EXPR:
6611 {
6612 tree e1 = tsubst (TREE_OPERAND (t, 0), args, complain,
6613 in_decl);
6614 tree e2 = tsubst (TREE_OPERAND (t, 1), args, complain,
6615 in_decl);
6616
6617 if (e1 == error_mark_node || e2 == error_mark_node)
6618 return error_mark_node;
6619
6620 return fold (build (TREE_CODE (t), TREE_TYPE (t), e1, e2));
6621 }
6622
6623 case NEGATE_EXPR:
6624 case NOP_EXPR:
6625 {
6626 tree e = tsubst (TREE_OPERAND (t, 0), args, complain,
6627 in_decl);
6628 if (e == error_mark_node)
6629 return error_mark_node;
6630
6631 return fold (build (TREE_CODE (t), TREE_TYPE (t), e));
6632 }
6633
6634 case TYPENAME_TYPE:
6635 {
6636 tree ctx = tsubst_aggr_type (TYPE_CONTEXT (t), args, complain,
6637 in_decl, /*entering_scope=*/1);
6638 tree f = tsubst_copy (TYPENAME_TYPE_FULLNAME (t), args,
6639 complain, in_decl);
6640
6641 if (ctx == error_mark_node || f == error_mark_node)
6642 return error_mark_node;
6643
6644 if (!IS_AGGR_TYPE (ctx))
6645 {
6646 if (complain)
6647 cp_error ("`%T' is not a class, struct, or union type",
6648 ctx);
6649 return error_mark_node;
6650 }
6651 else if (!uses_template_parms (ctx) && !TYPE_BEING_DEFINED (ctx))
6652 {
6653 /* Normally, make_typename_type does not require that the CTX
6654 have complete type in order to allow things like:
6655
6656 template <class T> struct S { typename S<T>::X Y; };
6657
6658 But, such constructs have already been resolved by this
6659 point, so here CTX really should have complete type, unless
6660 it's a partial instantiation. */
6661 ctx = complete_type (ctx);
6662 if (!COMPLETE_TYPE_P (ctx))
6663 {
6664 if (complain)
6665 incomplete_type_error (NULL_TREE, ctx);
6666 return error_mark_node;
6667 }
6668 }
6669
6670 f = make_typename_type (ctx, f, complain);
6671 if (f == error_mark_node)
6672 return f;
6673 return cp_build_qualified_type_real (f,
6674 CP_TYPE_QUALS (f)
6675 | CP_TYPE_QUALS (t),
6676 complain);
6677 }
6678
6679 case INDIRECT_REF:
6680 {
6681 tree e = tsubst (TREE_OPERAND (t, 0), args, complain,
6682 in_decl);
6683 if (e == error_mark_node)
6684 return error_mark_node;
6685 return make_pointer_declarator (type, e);
6686 }
6687
6688 case ADDR_EXPR:
6689 {
6690 tree e = tsubst (TREE_OPERAND (t, 0), args, complain,
6691 in_decl);
6692 if (e == error_mark_node)
6693 return error_mark_node;
6694 return make_reference_declarator (type, e);
6695 }
6696
6697 case ARRAY_REF:
6698 {
6699 tree e1 = tsubst (TREE_OPERAND (t, 0), args, complain,
6700 in_decl);
6701 tree e2 = tsubst_expr (TREE_OPERAND (t, 1), args, complain,
6702 in_decl);
6703 if (e1 == error_mark_node || e2 == error_mark_node)
6704 return error_mark_node;
6705
6706 return build_parse_node (ARRAY_REF, e1, e2, tsubst_expr);
6707 }
6708
6709 case CALL_EXPR:
6710 {
6711 tree e1 = tsubst (TREE_OPERAND (t, 0), args, complain,
6712 in_decl);
6713 tree e2 = (tsubst_call_declarator_parms
6714 (CALL_DECLARATOR_PARMS (t), args, complain, in_decl));
6715 tree e3 = tsubst (CALL_DECLARATOR_EXCEPTION_SPEC (t), args,
6716 complain, in_decl);
6717
6718 if (e1 == error_mark_node || e2 == error_mark_node
6719 || e3 == error_mark_node)
6720 return error_mark_node;
6721
6722 return make_call_declarator (e1, e2, CALL_DECLARATOR_QUALS (t), e3);
6723 }
6724
6725 case SCOPE_REF:
6726 {
6727 tree e1 = tsubst (TREE_OPERAND (t, 0), args, complain,
6728 in_decl);
6729 tree e2 = tsubst (TREE_OPERAND (t, 1), args, complain, in_decl);
6730 if (e1 == error_mark_node || e2 == error_mark_node)
6731 return error_mark_node;
6732
6733 return build_parse_node (TREE_CODE (t), e1, e2);
6734 }
6735
6736 case TYPEOF_TYPE:
6737 {
6738 tree e1 = tsubst_expr (TYPE_FIELDS (t), args, complain,
6739 in_decl);
6740 if (e1 == error_mark_node)
6741 return error_mark_node;
6742
6743 return TREE_TYPE (e1);
6744 }
6745
6746 case FUNCTION_NAME:
6747 {
6748 const char *name;
6749 int len;
6750 tree type;
6751 tree str;
6752
6753 /* This code should match declare_hidden_char_array in
6754 c-common.c. */
6755 name = (*decl_printable_name) (current_function_decl, 2);
6756 len = strlen (name) + 1;
6757 type = build_array_type (char_type_node,
6758 build_index_type (build_int_2 (len, 0)));
6759 str = build_string (len, name);
6760 TREE_TYPE (str) = type;
6761 return str;
6762 }
6763
6764 default:
6765 sorry ("use of `%s' in template",
6766 tree_code_name [(int) TREE_CODE (t)]);
6767 return error_mark_node;
6768 }
6769 }
6770
6771 /* Like tsubst, but deals with expressions. This function just replaces
6772 template parms; to finish processing the resultant expression, use
6773 tsubst_expr. */
6774
6775 tree
6776 tsubst_copy (t, args, complain, in_decl)
6777 tree t, args;
6778 int complain;
6779 tree in_decl;
6780 {
6781 enum tree_code code;
6782 tree r;
6783
6784 if (t == NULL_TREE || t == error_mark_node)
6785 return t;
6786
6787 code = TREE_CODE (t);
6788
6789 switch (code)
6790 {
6791 case PARM_DECL:
6792 return do_identifier (DECL_NAME (t), 0, NULL_TREE);
6793
6794 case CONST_DECL:
6795 {
6796 tree enum_type;
6797 tree v;
6798
6799 if (!DECL_CONTEXT (t))
6800 /* This is a global enumeration constant. */
6801 return t;
6802
6803 /* Unfortunately, we cannot just call lookup_name here.
6804 Consider:
6805
6806 template <int I> int f() {
6807 enum E { a = I };
6808 struct S { void g() { E e = a; } };
6809 };
6810
6811 When we instantiate f<7>::S::g(), say, lookup_name is not
6812 clever enough to find f<7>::a. */
6813 enum_type
6814 = tsubst_aggr_type (TREE_TYPE (t), args, complain, in_decl,
6815 /*entering_scope=*/0);
6816
6817 for (v = TYPE_VALUES (enum_type);
6818 v != NULL_TREE;
6819 v = TREE_CHAIN (v))
6820 if (TREE_PURPOSE (v) == DECL_NAME (t))
6821 return TREE_VALUE (v);
6822
6823 /* We didn't find the name. That should never happen; if
6824 name-lookup found it during preliminary parsing, we
6825 should find it again here during instantiation. */
6826 my_friendly_abort (0);
6827 }
6828 return t;
6829
6830 case FIELD_DECL:
6831 if (DECL_CONTEXT (t))
6832 {
6833 tree ctx;
6834
6835 ctx = tsubst_aggr_type (DECL_CONTEXT (t), args, complain, in_decl,
6836 /*entering_scope=*/1);
6837 if (ctx != DECL_CONTEXT (t))
6838 return lookup_field (ctx, DECL_NAME (t), 0, 0);
6839 }
6840 return t;
6841
6842 case VAR_DECL:
6843 case FUNCTION_DECL:
6844 if (DECL_LANG_SPECIFIC (t) && DECL_TEMPLATE_INFO (t))
6845 t = tsubst (t, args, complain, in_decl);
6846 mark_used (t);
6847 return t;
6848
6849 case TEMPLATE_DECL:
6850 if (is_member_template (t))
6851 return tsubst (t, args, complain, in_decl);
6852 else
6853 return t;
6854
6855 case LOOKUP_EXPR:
6856 {
6857 /* We must tsbust into a LOOKUP_EXPR in case the names to
6858 which it refers is a conversion operator; in that case the
6859 name will change. We avoid making unnecessary copies,
6860 however. */
6861
6862 tree id = tsubst_copy (TREE_OPERAND (t, 0), args, complain, in_decl);
6863
6864 if (id != TREE_OPERAND (t, 0))
6865 {
6866 r = build_nt (LOOKUP_EXPR, id);
6867 LOOKUP_EXPR_GLOBAL (r) = LOOKUP_EXPR_GLOBAL (t);
6868 t = r;
6869 }
6870
6871 return t;
6872 }
6873
6874 case CAST_EXPR:
6875 case REINTERPRET_CAST_EXPR:
6876 case CONST_CAST_EXPR:
6877 case STATIC_CAST_EXPR:
6878 case DYNAMIC_CAST_EXPR:
6879 case NOP_EXPR:
6880 return build1
6881 (code, tsubst (TREE_TYPE (t), args, complain, in_decl),
6882 tsubst_copy (TREE_OPERAND (t, 0), args, complain, in_decl));
6883
6884 case INDIRECT_REF:
6885 case PREDECREMENT_EXPR:
6886 case PREINCREMENT_EXPR:
6887 case POSTDECREMENT_EXPR:
6888 case POSTINCREMENT_EXPR:
6889 case NEGATE_EXPR:
6890 case TRUTH_NOT_EXPR:
6891 case BIT_NOT_EXPR:
6892 case ADDR_EXPR:
6893 case CONVERT_EXPR: /* Unary + */
6894 case SIZEOF_EXPR:
6895 case ALIGNOF_EXPR:
6896 case ARROW_EXPR:
6897 case THROW_EXPR:
6898 case TYPEID_EXPR:
6899 case REALPART_EXPR:
6900 case IMAGPART_EXPR:
6901 return build1
6902 (code, tsubst (TREE_TYPE (t), args, complain, in_decl),
6903 tsubst_copy (TREE_OPERAND (t, 0), args, complain, in_decl));
6904
6905 case PLUS_EXPR:
6906 case MINUS_EXPR:
6907 case MULT_EXPR:
6908 case TRUNC_DIV_EXPR:
6909 case CEIL_DIV_EXPR:
6910 case FLOOR_DIV_EXPR:
6911 case ROUND_DIV_EXPR:
6912 case EXACT_DIV_EXPR:
6913 case BIT_AND_EXPR:
6914 case BIT_ANDTC_EXPR:
6915 case BIT_IOR_EXPR:
6916 case BIT_XOR_EXPR:
6917 case TRUNC_MOD_EXPR:
6918 case FLOOR_MOD_EXPR:
6919 case TRUTH_ANDIF_EXPR:
6920 case TRUTH_ORIF_EXPR:
6921 case TRUTH_AND_EXPR:
6922 case TRUTH_OR_EXPR:
6923 case RSHIFT_EXPR:
6924 case LSHIFT_EXPR:
6925 case RROTATE_EXPR:
6926 case LROTATE_EXPR:
6927 case EQ_EXPR:
6928 case NE_EXPR:
6929 case MAX_EXPR:
6930 case MIN_EXPR:
6931 case LE_EXPR:
6932 case GE_EXPR:
6933 case LT_EXPR:
6934 case GT_EXPR:
6935 case COMPONENT_REF:
6936 case ARRAY_REF:
6937 case COMPOUND_EXPR:
6938 case SCOPE_REF:
6939 case DOTSTAR_EXPR:
6940 case MEMBER_REF:
6941 return build_nt
6942 (code, tsubst_copy (TREE_OPERAND (t, 0), args, complain, in_decl),
6943 tsubst_copy (TREE_OPERAND (t, 1), args, complain, in_decl));
6944
6945 case CALL_EXPR:
6946 {
6947 tree fn = TREE_OPERAND (t, 0);
6948 if (is_overloaded_fn (fn))
6949 fn = tsubst_copy (get_first_fn (fn), args, complain, in_decl);
6950 else
6951 /* Sometimes FN is a LOOKUP_EXPR. */
6952 fn = tsubst_copy (fn, args, complain, in_decl);
6953 return build_nt
6954 (code, fn, tsubst_copy (TREE_OPERAND (t, 1), args, complain,
6955 in_decl),
6956 NULL_TREE);
6957 }
6958
6959 case METHOD_CALL_EXPR:
6960 {
6961 tree name = TREE_OPERAND (t, 0);
6962 if (TREE_CODE (name) == BIT_NOT_EXPR)
6963 {
6964 name = tsubst_copy (TREE_OPERAND (name, 0), args,
6965 complain, in_decl);
6966 name = build1 (BIT_NOT_EXPR, NULL_TREE, name);
6967 }
6968 else if (TREE_CODE (name) == SCOPE_REF
6969 && TREE_CODE (TREE_OPERAND (name, 1)) == BIT_NOT_EXPR)
6970 {
6971 tree base = tsubst_copy (TREE_OPERAND (name, 0), args,
6972 complain, in_decl);
6973 name = TREE_OPERAND (name, 1);
6974 name = tsubst_copy (TREE_OPERAND (name, 0), args,
6975 complain, in_decl);
6976 name = build1 (BIT_NOT_EXPR, NULL_TREE, name);
6977 name = build_nt (SCOPE_REF, base, name);
6978 }
6979 else
6980 name = tsubst_copy (TREE_OPERAND (t, 0), args, complain, in_decl);
6981 return build_nt
6982 (code, name, tsubst_copy (TREE_OPERAND (t, 1), args,
6983 complain, in_decl),
6984 tsubst_copy (TREE_OPERAND (t, 2), args, complain, in_decl),
6985 NULL_TREE);
6986 }
6987
6988 case STMT_EXPR:
6989 /* This processing should really occur in tsubst_expr, However,
6990 tsubst_expr does not recurse into expressions, since it
6991 assumes that there aren't any statements inside them.
6992 Instead, it simply calls build_expr_from_tree. So, we need
6993 to expand the STMT_EXPR here. */
6994 if (!processing_template_decl)
6995 {
6996 tree stmt_expr = begin_stmt_expr ();
6997 tsubst_expr (STMT_EXPR_STMT (t), args,
6998 complain, in_decl);
6999 return finish_stmt_expr (stmt_expr);
7000 }
7001
7002 return t;
7003
7004 case COND_EXPR:
7005 case MODOP_EXPR:
7006 case PSEUDO_DTOR_EXPR:
7007 {
7008 r = build_nt
7009 (code, tsubst_copy (TREE_OPERAND (t, 0), args, complain, in_decl),
7010 tsubst_copy (TREE_OPERAND (t, 1), args, complain, in_decl),
7011 tsubst_copy (TREE_OPERAND (t, 2), args, complain, in_decl));
7012 return r;
7013 }
7014
7015 case NEW_EXPR:
7016 {
7017 r = build_nt
7018 (code, tsubst_copy (TREE_OPERAND (t, 0), args, complain, in_decl),
7019 tsubst_copy (TREE_OPERAND (t, 1), args, complain, in_decl),
7020 tsubst_copy (TREE_OPERAND (t, 2), args, complain, in_decl));
7021 NEW_EXPR_USE_GLOBAL (r) = NEW_EXPR_USE_GLOBAL (t);
7022 return r;
7023 }
7024
7025 case DELETE_EXPR:
7026 {
7027 r = build_nt
7028 (code, tsubst_copy (TREE_OPERAND (t, 0), args, complain, in_decl),
7029 tsubst_copy (TREE_OPERAND (t, 1), args, complain, in_decl));
7030 DELETE_EXPR_USE_GLOBAL (r) = DELETE_EXPR_USE_GLOBAL (t);
7031 DELETE_EXPR_USE_VEC (r) = DELETE_EXPR_USE_VEC (t);
7032 return r;
7033 }
7034
7035 case TEMPLATE_ID_EXPR:
7036 {
7037 /* Substituted template arguments */
7038 tree targs = tsubst_copy (TREE_OPERAND (t, 1), args, complain,
7039 in_decl);
7040
7041 if (targs && TREE_CODE (targs) == TREE_LIST)
7042 {
7043 tree chain;
7044 for (chain = targs; chain; chain = TREE_CHAIN (chain))
7045 TREE_VALUE (chain) = maybe_fold_nontype_arg (TREE_VALUE (chain));
7046 }
7047 else if (targs)
7048 {
7049 int i;
7050 for (i = 0; i < TREE_VEC_LENGTH (targs); ++i)
7051 TREE_VEC_ELT (targs, i)
7052 = maybe_fold_nontype_arg (TREE_VEC_ELT (targs, i));
7053 }
7054
7055 return lookup_template_function
7056 (tsubst_copy (TREE_OPERAND (t, 0), args, complain, in_decl), targs);
7057 }
7058
7059 case TREE_LIST:
7060 {
7061 tree purpose, value, chain;
7062
7063 if (t == void_list_node)
7064 return t;
7065
7066 purpose = TREE_PURPOSE (t);
7067 if (purpose)
7068 purpose = tsubst_copy (purpose, args, complain, in_decl);
7069 value = TREE_VALUE (t);
7070 if (value)
7071 value = tsubst_copy (value, args, complain, in_decl);
7072 chain = TREE_CHAIN (t);
7073 if (chain && chain != void_type_node)
7074 chain = tsubst_copy (chain, args, complain, in_decl);
7075 if (purpose == TREE_PURPOSE (t)
7076 && value == TREE_VALUE (t)
7077 && chain == TREE_CHAIN (t))
7078 return t;
7079 return tree_cons (purpose, value, chain);
7080 }
7081
7082 case RECORD_TYPE:
7083 case UNION_TYPE:
7084 case ENUMERAL_TYPE:
7085 case INTEGER_TYPE:
7086 case TEMPLATE_TYPE_PARM:
7087 case TEMPLATE_TEMPLATE_PARM:
7088 case TEMPLATE_PARM_INDEX:
7089 case POINTER_TYPE:
7090 case REFERENCE_TYPE:
7091 case OFFSET_TYPE:
7092 case FUNCTION_TYPE:
7093 case METHOD_TYPE:
7094 case ARRAY_TYPE:
7095 case TYPENAME_TYPE:
7096 case TYPE_DECL:
7097 return tsubst (t, args, complain, in_decl);
7098
7099 case IDENTIFIER_NODE:
7100 if (IDENTIFIER_TYPENAME_P (t))
7101 {
7102 tree new_type = tsubst (TREE_TYPE (t), args, complain, in_decl);
7103 if (flag_new_abi)
7104 return mangle_conv_op_name_for_type (new_type);
7105 else
7106 return (build_typename_overload (new_type));
7107 }
7108 else
7109 return t;
7110
7111 case CONSTRUCTOR:
7112 {
7113 r = build
7114 (CONSTRUCTOR, tsubst (TREE_TYPE (t), args, complain, in_decl),
7115 NULL_TREE, tsubst_copy (CONSTRUCTOR_ELTS (t), args,
7116 complain, in_decl));
7117 TREE_HAS_CONSTRUCTOR (r) = TREE_HAS_CONSTRUCTOR (t);
7118 return r;
7119 }
7120
7121 case VA_ARG_EXPR:
7122 return build_x_va_arg (tsubst_copy (TREE_OPERAND (t, 0), args, complain,
7123 in_decl),
7124 tsubst (TREE_TYPE (t), args, complain, in_decl));
7125
7126 case FUNCTION_NAME:
7127 return tsubst (t, args, complain, in_decl);
7128
7129 default:
7130 return t;
7131 }
7132 }
7133
7134 /* Like tsubst_copy, but also does semantic processing. */
7135
7136 tree
7137 tsubst_expr (t, args, complain, in_decl)
7138 tree t, args;
7139 int complain;
7140 tree in_decl;
7141 {
7142 tree stmt;
7143
7144 if (t == NULL_TREE || t == error_mark_node)
7145 return t;
7146
7147 if (processing_template_decl)
7148 return tsubst_copy (t, args, complain, in_decl);
7149
7150 switch (TREE_CODE (t))
7151 {
7152 case RETURN_INIT:
7153 prep_stmt (t);
7154 finish_named_return_value
7155 (TREE_OPERAND (t, 0),
7156 tsubst_expr (TREE_OPERAND (t, 1), args, /*complain=*/1, in_decl));
7157 tsubst_expr (TREE_CHAIN (t), args, complain, in_decl);
7158 break;
7159
7160 case CTOR_INITIALIZER:
7161 {
7162 tree member_init_list;
7163 tree base_init_list;
7164
7165 prep_stmt (t);
7166 member_init_list
7167 = tsubst_initializer_list (TREE_OPERAND (t, 0), args);
7168 base_init_list
7169 = tsubst_initializer_list (TREE_OPERAND (t, 1), args);
7170 setup_vtbl_ptr (member_init_list, base_init_list);
7171 tsubst_expr (TREE_CHAIN (t), args, complain, in_decl);
7172 break;
7173 }
7174
7175 case RETURN_STMT:
7176 prep_stmt (t);
7177 finish_return_stmt (tsubst_expr (RETURN_EXPR (t),
7178 args, complain, in_decl));
7179 break;
7180
7181 case EXPR_STMT:
7182 prep_stmt (t);
7183 finish_expr_stmt (tsubst_expr (EXPR_STMT_EXPR (t),
7184 args, complain, in_decl));
7185 break;
7186
7187 case DECL_STMT:
7188 {
7189 tree decl;
7190 tree init;
7191
7192 prep_stmt (t);
7193 decl = DECL_STMT_DECL (t);
7194 if (TREE_CODE (decl) == LABEL_DECL)
7195 finish_label_decl (DECL_NAME (decl));
7196 else
7197 {
7198 init = DECL_INITIAL (decl);
7199 decl = tsubst (decl, args, complain, in_decl);
7200 init = tsubst_expr (init, args, complain, in_decl);
7201 if (init)
7202 DECL_INITIAL (decl) = error_mark_node;
7203 /* By marking the declaration as instantiated, we avoid
7204 trying to instantiate it. Since instantiate_decl can't
7205 handle local variables, and since we've already done
7206 all that needs to be done, that's the right thing to
7207 do. */
7208 if (TREE_CODE (decl) == VAR_DECL)
7209 DECL_TEMPLATE_INSTANTIATED (decl) = 1;
7210 maybe_push_decl (decl);
7211 cp_finish_decl (decl, init, NULL_TREE, 0);
7212 }
7213 return decl;
7214 }
7215
7216 case FOR_STMT:
7217 {
7218 tree tmp;
7219 prep_stmt (t);
7220
7221 stmt = begin_for_stmt ();
7222 for (tmp = FOR_INIT_STMT (t); tmp; tmp = TREE_CHAIN (tmp))
7223 tsubst_expr (tmp, args, complain, in_decl);
7224 finish_for_init_stmt (stmt);
7225 finish_for_cond (tsubst_expr (FOR_COND (t), args,
7226 complain, in_decl),
7227 stmt);
7228 tmp = tsubst_expr (FOR_EXPR (t), args, complain, in_decl);
7229 finish_for_expr (tmp, stmt);
7230 tsubst_expr (FOR_BODY (t), args, complain, in_decl);
7231 finish_for_stmt (stmt);
7232 }
7233 break;
7234
7235 case WHILE_STMT:
7236 {
7237 prep_stmt (t);
7238 stmt = begin_while_stmt ();
7239 finish_while_stmt_cond (tsubst_expr (WHILE_COND (t),
7240 args, complain, in_decl),
7241 stmt);
7242 tsubst_expr (WHILE_BODY (t), args, complain, in_decl);
7243 finish_while_stmt (stmt);
7244 }
7245 break;
7246
7247 case DO_STMT:
7248 {
7249 prep_stmt (t);
7250 stmt = begin_do_stmt ();
7251 tsubst_expr (DO_BODY (t), args, complain, in_decl);
7252 finish_do_body (stmt);
7253 finish_do_stmt (tsubst_expr (DO_COND (t), args,
7254 complain, in_decl),
7255 stmt);
7256 }
7257 break;
7258
7259 case IF_STMT:
7260 {
7261 tree tmp;
7262
7263 prep_stmt (t);
7264 stmt = begin_if_stmt ();
7265 finish_if_stmt_cond (tsubst_expr (IF_COND (t),
7266 args, complain, in_decl),
7267 stmt);
7268
7269 if (tmp = THEN_CLAUSE (t), tmp)
7270 {
7271 tsubst_expr (tmp, args, complain, in_decl);
7272 finish_then_clause (stmt);
7273 }
7274
7275 if (tmp = ELSE_CLAUSE (t), tmp)
7276 {
7277 begin_else_clause ();
7278 tsubst_expr (tmp, args, complain, in_decl);
7279 finish_else_clause (stmt);
7280 }
7281
7282 finish_if_stmt ();
7283 }
7284 break;
7285
7286 case COMPOUND_STMT:
7287 {
7288 tree substmt;
7289
7290 prep_stmt (t);
7291 stmt = begin_compound_stmt (COMPOUND_STMT_NO_SCOPE (t));
7292 for (substmt = COMPOUND_BODY (t);
7293 substmt != NULL_TREE;
7294 substmt = TREE_CHAIN (substmt))
7295 tsubst_expr (substmt, args, complain, in_decl);
7296 return finish_compound_stmt (COMPOUND_STMT_NO_SCOPE (t), stmt);
7297 }
7298 break;
7299
7300 case BREAK_STMT:
7301 prep_stmt (t);
7302 finish_break_stmt ();
7303 break;
7304
7305 case CONTINUE_STMT:
7306 prep_stmt (t);
7307 finish_continue_stmt ();
7308 break;
7309
7310 case SWITCH_STMT:
7311 {
7312 tree val;
7313
7314 prep_stmt (t);
7315 stmt = begin_switch_stmt ();
7316 val = tsubst_expr (SWITCH_COND (t), args, complain, in_decl);
7317 finish_switch_cond (val, stmt);
7318 tsubst_expr (SWITCH_BODY (t), args, complain, in_decl);
7319 finish_switch_stmt (stmt);
7320 }
7321 break;
7322
7323 case CASE_LABEL:
7324 prep_stmt (t);
7325 finish_case_label (tsubst_expr (CASE_LOW (t), args, complain, in_decl),
7326 tsubst_expr (CASE_HIGH (t), args, complain, in_decl));
7327 break;
7328
7329 case LABEL_STMT:
7330 lineno = STMT_LINENO (t);
7331 finish_label_stmt (DECL_NAME (LABEL_STMT_LABEL (t)));
7332 break;
7333
7334 case GOTO_STMT:
7335 prep_stmt (t);
7336 t = GOTO_DESTINATION (t);
7337 if (TREE_CODE (t) != LABEL_DECL)
7338 /* Computed goto's must be tsubst'd into. On the other hand,
7339 non-computed gotos must not be; the identifier in question
7340 will have no binding. */
7341 t = tsubst_expr (t, args, complain, in_decl);
7342 else
7343 t = DECL_NAME (t);
7344 finish_goto_stmt (t);
7345 break;
7346
7347 case ASM_STMT:
7348 prep_stmt (t);
7349 finish_asm_stmt (ASM_CV_QUAL (t),
7350 tsubst_expr (ASM_STRING (t), args, complain, in_decl),
7351 tsubst_expr (ASM_OUTPUTS (t), args, complain, in_decl),
7352 tsubst_expr (ASM_INPUTS (t), args, complain, in_decl),
7353 tsubst_expr (ASM_CLOBBERS (t), args, complain,
7354 in_decl));
7355 break;
7356
7357 case TRY_BLOCK:
7358 prep_stmt (t);
7359 if (CLEANUP_P (t))
7360 {
7361 stmt = begin_try_block ();
7362 tsubst_expr (TRY_STMTS (t), args, complain, in_decl);
7363 finish_cleanup_try_block (stmt);
7364 finish_cleanup (tsubst_expr (TRY_HANDLERS (t), args,
7365 complain, in_decl),
7366 stmt);
7367 }
7368 else
7369 {
7370 tree handler;
7371
7372 if (FN_TRY_BLOCK_P (t))
7373 stmt = begin_function_try_block ();
7374 else
7375 stmt = begin_try_block ();
7376
7377 tsubst_expr (TRY_STMTS (t), args, complain, in_decl);
7378
7379 if (FN_TRY_BLOCK_P (t))
7380 finish_function_try_block (stmt);
7381 else
7382 finish_try_block (stmt);
7383
7384 handler = TRY_HANDLERS (t);
7385 for (; handler; handler = TREE_CHAIN (handler))
7386 tsubst_expr (handler, args, complain, in_decl);
7387 if (FN_TRY_BLOCK_P (t))
7388 finish_function_handler_sequence (stmt);
7389 else
7390 finish_handler_sequence (stmt);
7391 }
7392 break;
7393
7394 case HANDLER:
7395 {
7396 tree decl;
7397 tree blocks;
7398
7399 prep_stmt (t);
7400 stmt = begin_handler ();
7401 if (HANDLER_PARMS (t))
7402 {
7403 decl = DECL_STMT_DECL (HANDLER_PARMS (t));
7404 decl = tsubst (decl, args, complain, in_decl);
7405 /* Prevent instantiate_decl from trying to instantiate
7406 this variable. We've already done all that needs to be
7407 done. */
7408 DECL_TEMPLATE_INSTANTIATED (decl) = 1;
7409 }
7410 else
7411 decl = NULL_TREE;
7412 blocks = finish_handler_parms (decl, stmt);
7413 tsubst_expr (HANDLER_BODY (t), args, complain, in_decl);
7414 finish_handler (blocks, stmt);
7415 }
7416 break;
7417
7418 case TAG_DEFN:
7419 prep_stmt (t);
7420 t = TREE_TYPE (t);
7421 tsubst (t, args, complain, NULL_TREE);
7422 break;
7423
7424 default:
7425 return build_expr_from_tree (tsubst_copy (t, args, complain, in_decl));
7426 }
7427 return NULL_TREE;
7428 }
7429
7430 /* TMPL is a TEMPLATE_DECL for a cloned constructor or destructor.
7431 Instantiate it with the ARGS. */
7432
7433 static tree
7434 instantiate_clone (tmpl, args)
7435 tree tmpl;
7436 tree args;
7437 {
7438 tree spec;
7439 tree clone;
7440
7441 /* Instantiated the cloned function, rather than the clone. */
7442 spec = instantiate_template (DECL_CLONED_FUNCTION (tmpl), args);
7443
7444 /* Then, see if we've already cloned the instantiation. */
7445 for (clone = TREE_CHAIN (spec);
7446 clone && DECL_CLONED_FUNCTION_P (clone);
7447 clone = TREE_CHAIN (clone))
7448 if (DECL_NAME (clone) == DECL_NAME (tmpl))
7449 return clone;
7450
7451 /* If we haven't, do so know. */
7452 if (!clone)
7453 clone_function_decl (spec, /*update_method_vec_p=*/0);
7454
7455 /* Look again. */
7456 for (clone = TREE_CHAIN (spec);
7457 clone && DECL_CLONED_FUNCTION_P (clone);
7458 clone = TREE_CHAIN (clone))
7459 if (DECL_NAME (clone) == DECL_NAME (tmpl))
7460 return clone;
7461
7462 /* We should always have found the clone by now. */
7463 my_friendly_abort (20000411);
7464 return NULL_TREE;
7465 }
7466
7467 /* Instantiate the indicated variable or function template TMPL with
7468 the template arguments in TARG_PTR. */
7469
7470 tree
7471 instantiate_template (tmpl, targ_ptr)
7472 tree tmpl, targ_ptr;
7473 {
7474 tree fndecl;
7475 tree gen_tmpl;
7476 tree spec;
7477 int i, len;
7478 tree inner_args;
7479
7480 if (tmpl == error_mark_node)
7481 return error_mark_node;
7482
7483 my_friendly_assert (TREE_CODE (tmpl) == TEMPLATE_DECL, 283);
7484
7485 /* If this function is a clone, handle it specially. */
7486 if (DECL_CLONED_FUNCTION_P (tmpl))
7487 return instantiate_clone (tmpl, targ_ptr);
7488
7489 /* Check to see if we already have this specialization. */
7490 spec = retrieve_specialization (tmpl, targ_ptr);
7491 if (spec != NULL_TREE)
7492 return spec;
7493
7494 gen_tmpl = most_general_template (tmpl);
7495 if (tmpl != gen_tmpl)
7496 {
7497 /* The TMPL is a partial instantiation. To get a full set of
7498 arguments we must add the arguments used to perform the
7499 partial instantiation. */
7500 targ_ptr = add_outermost_template_args (DECL_TI_ARGS (tmpl),
7501 targ_ptr);
7502
7503 /* Check to see if we already have this specialization. */
7504 spec = retrieve_specialization (gen_tmpl, targ_ptr);
7505 if (spec != NULL_TREE)
7506 return spec;
7507 }
7508
7509 len = DECL_NTPARMS (gen_tmpl);
7510 inner_args = INNERMOST_TEMPLATE_ARGS (targ_ptr);
7511 i = len;
7512 while (i--)
7513 {
7514 tree t = TREE_VEC_ELT (inner_args, i);
7515 if (TYPE_P (t))
7516 {
7517 tree nt = target_type (t);
7518 if (IS_AGGR_TYPE (nt) && decl_function_context (TYPE_MAIN_DECL (nt)))
7519 {
7520 cp_error ("type `%T' composed from a local class is not a valid template-argument", t);
7521 cp_error (" trying to instantiate `%D'", gen_tmpl);
7522 return error_mark_node;
7523 }
7524 }
7525 }
7526
7527 /* substitute template parameters */
7528 fndecl = tsubst (DECL_TEMPLATE_RESULT (gen_tmpl),
7529 targ_ptr, /*complain=*/1, gen_tmpl);
7530 /* The DECL_TI_TEMPLATE should always be the immediate parent
7531 template, not the most general template. */
7532 DECL_TI_TEMPLATE (fndecl) = tmpl;
7533
7534 if (flag_external_templates)
7535 add_pending_template (fndecl);
7536
7537 return fndecl;
7538 }
7539
7540 /* Push the name of the class template into the scope of the instantiation. */
7541
7542 void
7543 overload_template_name (type)
7544 tree type;
7545 {
7546 tree id = DECL_NAME (CLASSTYPE_TI_TEMPLATE (type));
7547 tree decl;
7548
7549 if (IDENTIFIER_CLASS_VALUE (id)
7550 && TREE_TYPE (IDENTIFIER_CLASS_VALUE (id)) == type)
7551 return;
7552
7553 decl = build_decl (TYPE_DECL, id, type);
7554 DECL_ARTIFICIAL (decl) = 1;
7555 pushdecl_class_level (decl);
7556 }
7557
7558 /* The FN is a TEMPLATE_DECL for a function. The ARGS are the
7559 arguments that are being used when calling it. TARGS is a vector
7560 into which the deduced template arguments are placed.
7561
7562 Return zero for success, 2 for an incomplete match that doesn't resolve
7563 all the types, and 1 for complete failure. An error message will be
7564 printed only for an incomplete match.
7565
7566 If FN is a conversion operator, RETURN_TYPE is the type desired as
7567 the result of the conversion operator.
7568
7569 TPARMS is a vector of template parameters.
7570
7571 The EXPLICIT_TARGS are explicit template arguments provided via a
7572 template-id.
7573
7574 The parameter STRICT is one of:
7575
7576 DEDUCE_CALL:
7577 We are deducing arguments for a function call, as in
7578 [temp.deduct.call].
7579
7580 DEDUCE_CONV:
7581 We are deducing arguments for a conversion function, as in
7582 [temp.deduct.conv].
7583
7584 DEDUCE_EXACT:
7585 We are deducing arguments when calculating the partial
7586 ordering between specializations of function or class
7587 templates, as in [temp.func.order] and [temp.class.order],
7588 when doing an explicit instantiation as in [temp.explicit],
7589 when determining an explicit specialization as in
7590 [temp.expl.spec], or when taking the address of a function
7591 template, as in [temp.deduct.funcaddr].
7592
7593 The other arguments are as for type_unification. */
7594
7595 int
7596 fn_type_unification (fn, explicit_targs, targs, args, return_type,
7597 strict)
7598 tree fn, explicit_targs, targs, args, return_type;
7599 unification_kind_t strict;
7600 {
7601 tree parms;
7602 tree fntype;
7603 int result;
7604
7605 my_friendly_assert (TREE_CODE (fn) == TEMPLATE_DECL, 0);
7606
7607 fntype = TREE_TYPE (fn);
7608 if (explicit_targs)
7609 {
7610 /* [temp.deduct]
7611
7612 The specified template arguments must match the template
7613 parameters in kind (i.e., type, nontype, template), and there
7614 must not be more arguments than there are parameters;
7615 otherwise type deduction fails.
7616
7617 Nontype arguments must match the types of the corresponding
7618 nontype template parameters, or must be convertible to the
7619 types of the corresponding nontype parameters as specified in
7620 _temp.arg.nontype_, otherwise type deduction fails.
7621
7622 All references in the function type of the function template
7623 to the corresponding template parameters are replaced by the
7624 specified template argument values. If a substitution in a
7625 template parameter or in the function type of the function
7626 template results in an invalid type, type deduction fails. */
7627 int i;
7628 tree converted_args;
7629
7630 converted_args
7631 = (coerce_template_parms (DECL_INNERMOST_TEMPLATE_PARMS (fn),
7632 explicit_targs, NULL_TREE, /*complain=*/0,
7633 /*require_all_arguments=*/0));
7634 if (converted_args == error_mark_node)
7635 return 1;
7636
7637 fntype = tsubst (fntype, converted_args, /*complain=*/0, NULL_TREE);
7638 if (fntype == error_mark_node)
7639 return 1;
7640
7641 /* Place the explicitly specified arguments in TARGS. */
7642 for (i = 0; i < TREE_VEC_LENGTH (targs); i++)
7643 TREE_VEC_ELT (targs, i) = TREE_VEC_ELT (converted_args, i);
7644 }
7645
7646 parms = TYPE_ARG_TYPES (fntype);
7647
7648 if (DECL_CONV_FN_P (fn))
7649 {
7650 /* This is a template conversion operator. Remove `this', since
7651 we could be comparing conversions from different classes. */
7652 parms = TREE_CHAIN (parms);
7653 args = TREE_CHAIN (args);
7654 my_friendly_assert (return_type != NULL_TREE, 20000227);
7655 }
7656
7657 if (return_type)
7658 {
7659 /* We've been given a return type to match, prepend it. */
7660 parms = tree_cons (NULL_TREE, TREE_TYPE (fntype), parms);
7661 args = tree_cons (NULL_TREE, return_type, args);
7662 }
7663
7664 /* We allow incomplete unification without an error message here
7665 because the standard doesn't seem to explicitly prohibit it. Our
7666 callers must be ready to deal with unification failures in any
7667 event. */
7668 result = type_unification_real (DECL_INNERMOST_TEMPLATE_PARMS (fn),
7669 targs, parms, args, /*subr=*/0,
7670 strict, /*allow_incomplete*/1);
7671
7672 if (result == 0)
7673 /* All is well so far. Now, check:
7674
7675 [temp.deduct]
7676
7677 When all template arguments have been deduced, all uses of
7678 template parameters in nondeduced contexts are replaced with
7679 the corresponding deduced argument values. If the
7680 substitution results in an invalid type, as described above,
7681 type deduction fails. */
7682 if (tsubst (TREE_TYPE (fn), targs, /*complain=*/0, NULL_TREE)
7683 == error_mark_node)
7684 return 1;
7685
7686 return result;
7687 }
7688
7689 /* Adjust types before performing type deduction, as described in
7690 [temp.deduct.call] and [temp.deduct.conv]. The rules in these two
7691 sections are symmetric. PARM is the type of a function parameter
7692 or the return type of the conversion function. ARG is the type of
7693 the argument passed to the call, or the type of the value
7694 intialized with the result of the conversion function. */
7695
7696 static void
7697 maybe_adjust_types_for_deduction (strict, parm, arg)
7698 unification_kind_t strict;
7699 tree* parm;
7700 tree* arg;
7701 {
7702 switch (strict)
7703 {
7704 case DEDUCE_CALL:
7705 break;
7706
7707 case DEDUCE_CONV:
7708 {
7709 /* Swap PARM and ARG throughout the remainder of this
7710 function; the handling is precisely symmetric since PARM
7711 will initialize ARG rather than vice versa. */
7712 tree* temp = parm;
7713 parm = arg;
7714 arg = temp;
7715 break;
7716 }
7717
7718 case DEDUCE_EXACT:
7719 /* There is nothing to do in this case. */
7720 return;
7721
7722 default:
7723 my_friendly_abort (0);
7724 }
7725
7726 if (TREE_CODE (*parm) != REFERENCE_TYPE)
7727 {
7728 /* [temp.deduct.call]
7729
7730 If P is not a reference type:
7731
7732 --If A is an array type, the pointer type produced by the
7733 array-to-pointer standard conversion (_conv.array_) is
7734 used in place of A for type deduction; otherwise,
7735
7736 --If A is a function type, the pointer type produced by
7737 the function-to-pointer standard conversion
7738 (_conv.func_) is used in place of A for type deduction;
7739 otherwise,
7740
7741 --If A is a cv-qualified type, the top level
7742 cv-qualifiers of A's type are ignored for type
7743 deduction. */
7744 if (TREE_CODE (*arg) == ARRAY_TYPE)
7745 *arg = build_pointer_type (TREE_TYPE (*arg));
7746 else if (TREE_CODE (*arg) == FUNCTION_TYPE)
7747 *arg = build_pointer_type (*arg);
7748 else
7749 *arg = TYPE_MAIN_VARIANT (*arg);
7750 }
7751
7752 /* [temp.deduct.call]
7753
7754 If P is a cv-qualified type, the top level cv-qualifiers
7755 of P's type are ignored for type deduction. If P is a
7756 reference type, the type referred to by P is used for
7757 type deduction. */
7758 *parm = TYPE_MAIN_VARIANT (*parm);
7759 if (TREE_CODE (*parm) == REFERENCE_TYPE)
7760 *parm = TREE_TYPE (*parm);
7761 }
7762
7763 /* Like type_unfication.
7764
7765 If SUBR is 1, we're being called recursively (to unify the
7766 arguments of a function or method parameter of a function
7767 template). */
7768
7769 static int
7770 type_unification_real (tparms, targs, parms, args, subr,
7771 strict, allow_incomplete)
7772 tree tparms, targs, parms, args;
7773 int subr;
7774 unification_kind_t strict;
7775 int allow_incomplete;
7776 {
7777 tree parm, arg;
7778 int i;
7779 int ntparms = TREE_VEC_LENGTH (tparms);
7780 int sub_strict;
7781
7782 my_friendly_assert (TREE_CODE (tparms) == TREE_VEC, 289);
7783 my_friendly_assert (parms == NULL_TREE
7784 || TREE_CODE (parms) == TREE_LIST, 290);
7785 /* ARGS could be NULL (via a call from parse.y to
7786 build_x_function_call). */
7787 if (args)
7788 my_friendly_assert (TREE_CODE (args) == TREE_LIST, 291);
7789 my_friendly_assert (ntparms > 0, 292);
7790
7791 switch (strict)
7792 {
7793 case DEDUCE_CALL:
7794 sub_strict = UNIFY_ALLOW_MORE_CV_QUAL | UNIFY_ALLOW_DERIVED;
7795 break;
7796
7797 case DEDUCE_CONV:
7798 sub_strict = UNIFY_ALLOW_LESS_CV_QUAL;
7799 break;
7800
7801 case DEDUCE_EXACT:
7802 sub_strict = UNIFY_ALLOW_NONE;
7803 break;
7804
7805 default:
7806 my_friendly_abort (0);
7807 }
7808
7809 while (parms
7810 && parms != void_list_node
7811 && args
7812 && args != void_list_node)
7813 {
7814 parm = TREE_VALUE (parms);
7815 parms = TREE_CHAIN (parms);
7816 arg = TREE_VALUE (args);
7817 args = TREE_CHAIN (args);
7818
7819 if (arg == error_mark_node)
7820 return 1;
7821 if (arg == unknown_type_node)
7822 /* We can't deduce anything from this, but we might get all the
7823 template args from other function args. */
7824 continue;
7825
7826 /* Conversions will be performed on a function argument that
7827 corresponds with a function parameter that contains only
7828 non-deducible template parameters and explicitly specified
7829 template parameters. */
7830 if (! uses_template_parms (parm))
7831 {
7832 tree type;
7833
7834 if (!TYPE_P (arg))
7835 type = TREE_TYPE (arg);
7836 else
7837 {
7838 type = arg;
7839 arg = NULL_TREE;
7840 }
7841
7842 if (strict == DEDUCE_EXACT)
7843 {
7844 if (same_type_p (parm, type))
7845 continue;
7846 }
7847 else
7848 /* It might work; we shouldn't check now, because we might
7849 get into infinite recursion. Overload resolution will
7850 handle it. */
7851 continue;
7852
7853 return 1;
7854 }
7855
7856 if (!TYPE_P (arg))
7857 {
7858 my_friendly_assert (TREE_TYPE (arg) != NULL_TREE, 293);
7859 if (type_unknown_p (arg))
7860 {
7861 /* [temp.deduct.type] A template-argument can be deduced from
7862 a pointer to function or pointer to member function
7863 argument if the set of overloaded functions does not
7864 contain function templates and at most one of a set of
7865 overloaded functions provides a unique match. */
7866
7867 if (resolve_overloaded_unification
7868 (tparms, targs, parm, arg, strict, sub_strict)
7869 != 0)
7870 return 1;
7871 continue;
7872 }
7873 arg = TREE_TYPE (arg);
7874 }
7875
7876 if (!subr)
7877 maybe_adjust_types_for_deduction (strict, &parm, &arg);
7878
7879 switch (unify (tparms, targs, parm, arg, sub_strict))
7880 {
7881 case 0:
7882 break;
7883 case 1:
7884 return 1;
7885 }
7886 }
7887 /* Fail if we've reached the end of the parm list, and more args
7888 are present, and the parm list isn't variadic. */
7889 if (args && args != void_list_node && parms == void_list_node)
7890 return 1;
7891 /* Fail if parms are left and they don't have default values. */
7892 if (parms
7893 && parms != void_list_node
7894 && TREE_PURPOSE (parms) == NULL_TREE)
7895 return 1;
7896 if (!subr)
7897 for (i = 0; i < ntparms; i++)
7898 if (TREE_VEC_ELT (targs, i) == NULL_TREE)
7899 {
7900 if (!allow_incomplete)
7901 error ("incomplete type unification");
7902 return 2;
7903 }
7904 return 0;
7905 }
7906
7907 /* Subroutine of type_unification_real. Args are like the variables at the
7908 call site. ARG is an overloaded function (or template-id); we try
7909 deducing template args from each of the overloads, and if only one
7910 succeeds, we go with that. Modifies TARGS and returns 0 on success. */
7911
7912 static int
7913 resolve_overloaded_unification (tparms, targs, parm, arg, strict,
7914 sub_strict)
7915 tree tparms, targs, parm, arg;
7916 unification_kind_t strict;
7917 int sub_strict;
7918 {
7919 tree tempargs = copy_node (targs);
7920 int good = 0;
7921
7922 if (TREE_CODE (arg) == ADDR_EXPR)
7923 arg = TREE_OPERAND (arg, 0);
7924
7925 if (TREE_CODE (arg) == COMPONENT_REF)
7926 /* Handle `&x' where `x' is some static or non-static member
7927 function name. */
7928 arg = TREE_OPERAND (arg, 1);
7929
7930 if (TREE_CODE (arg) == OFFSET_REF)
7931 arg = TREE_OPERAND (arg, 1);
7932
7933 /* Strip baselink information. */
7934 while (TREE_CODE (arg) == TREE_LIST)
7935 arg = TREE_VALUE (arg);
7936
7937 if (TREE_CODE (arg) == TEMPLATE_ID_EXPR)
7938 {
7939 /* If we got some explicit template args, we need to plug them into
7940 the affected templates before we try to unify, in case the
7941 explicit args will completely resolve the templates in question. */
7942
7943 tree expl_subargs = TREE_OPERAND (arg, 1);
7944 arg = TREE_OPERAND (arg, 0);
7945
7946 for (; arg; arg = OVL_NEXT (arg))
7947 {
7948 tree fn = OVL_CURRENT (arg);
7949 tree subargs, elem;
7950
7951 if (TREE_CODE (fn) != TEMPLATE_DECL)
7952 continue;
7953
7954 subargs = get_bindings_overload (fn, DECL_TEMPLATE_RESULT (fn),
7955 expl_subargs);
7956 if (subargs)
7957 {
7958 elem = tsubst (TREE_TYPE (fn), subargs, /*complain=*/0,
7959 NULL_TREE);
7960 if (TREE_CODE (elem) == METHOD_TYPE)
7961 elem = build_ptrmemfunc_type (build_pointer_type (elem));
7962 good += try_one_overload (tparms, targs, tempargs, parm, elem,
7963 strict, sub_strict);
7964 }
7965 }
7966 }
7967 else if (TREE_CODE (arg) == OVERLOAD)
7968 {
7969 for (; arg; arg = OVL_NEXT (arg))
7970 {
7971 tree type = TREE_TYPE (OVL_CURRENT (arg));
7972 if (TREE_CODE (type) == METHOD_TYPE)
7973 type = build_ptrmemfunc_type (build_pointer_type (type));
7974 good += try_one_overload (tparms, targs, tempargs, parm,
7975 type,
7976 strict, sub_strict);
7977 }
7978 }
7979 else
7980 my_friendly_abort (981006);
7981
7982 /* [temp.deduct.type] A template-argument can be deduced from a pointer
7983 to function or pointer to member function argument if the set of
7984 overloaded functions does not contain function templates and at most
7985 one of a set of overloaded functions provides a unique match.
7986
7987 So if we found multiple possibilities, we return success but don't
7988 deduce anything. */
7989
7990 if (good == 1)
7991 {
7992 int i = TREE_VEC_LENGTH (targs);
7993 for (; i--; )
7994 if (TREE_VEC_ELT (tempargs, i))
7995 TREE_VEC_ELT (targs, i) = TREE_VEC_ELT (tempargs, i);
7996 }
7997 if (good)
7998 return 0;
7999
8000 return 1;
8001 }
8002
8003 /* Subroutine of resolve_overloaded_unification; does deduction for a single
8004 overload. Fills TARGS with any deduced arguments, or error_mark_node if
8005 different overloads deduce different arguments for a given parm.
8006 Returns 1 on success. */
8007
8008 static int
8009 try_one_overload (tparms, orig_targs, targs, parm, arg, strict,
8010 sub_strict)
8011 tree tparms, orig_targs, targs, parm, arg;
8012 unification_kind_t strict;
8013 int sub_strict;
8014 {
8015 int nargs;
8016 tree tempargs;
8017 int i;
8018
8019 /* [temp.deduct.type] A template-argument can be deduced from a pointer
8020 to function or pointer to member function argument if the set of
8021 overloaded functions does not contain function templates and at most
8022 one of a set of overloaded functions provides a unique match.
8023
8024 So if this is a template, just return success. */
8025
8026 if (uses_template_parms (arg))
8027 return 1;
8028
8029 maybe_adjust_types_for_deduction (strict, &parm, &arg);
8030
8031 /* We don't copy orig_targs for this because if we have already deduced
8032 some template args from previous args, unify would complain when we
8033 try to deduce a template parameter for the same argument, even though
8034 there isn't really a conflict. */
8035 nargs = TREE_VEC_LENGTH (targs);
8036 tempargs = make_tree_vec (nargs);
8037
8038 if (unify (tparms, tempargs, parm, arg, sub_strict) != 0)
8039 return 0;
8040
8041 /* First make sure we didn't deduce anything that conflicts with
8042 explicitly specified args. */
8043 for (i = nargs; i--; )
8044 {
8045 tree elt = TREE_VEC_ELT (tempargs, i);
8046 tree oldelt = TREE_VEC_ELT (orig_targs, i);
8047
8048 if (elt == NULL_TREE)
8049 continue;
8050 else if (uses_template_parms (elt))
8051 {
8052 /* Since we're unifying against ourselves, we will fill in template
8053 args used in the function parm list with our own template parms.
8054 Discard them. */
8055 TREE_VEC_ELT (tempargs, i) = NULL_TREE;
8056 continue;
8057 }
8058 else if (oldelt && ! template_args_equal (oldelt, elt))
8059 return 0;
8060 }
8061
8062 for (i = nargs; i--; )
8063 {
8064 tree elt = TREE_VEC_ELT (tempargs, i);
8065
8066 if (elt)
8067 TREE_VEC_ELT (targs, i) = elt;
8068 }
8069
8070 return 1;
8071 }
8072
8073 /* PARM is a template class (perhaps with unbound template
8074 parameters). ARG is a fully instantiated type. If ARG can be
8075 bound to PARM, return ARG, otherwise return NULL_TREE. TPARMS and
8076 TARGS are as for unify. */
8077
8078 static tree
8079 try_class_unification (tparms, targs, parm, arg)
8080 tree tparms;
8081 tree targs;
8082 tree parm;
8083 tree arg;
8084 {
8085 int i;
8086 tree copy_of_targs;
8087
8088 if (!CLASSTYPE_TEMPLATE_INFO (arg)
8089 || CLASSTYPE_TI_TEMPLATE (arg) != CLASSTYPE_TI_TEMPLATE (parm))
8090 return NULL_TREE;
8091
8092 /* We need to make a new template argument vector for the call to
8093 unify. If we used TARGS, we'd clutter it up with the result of
8094 the attempted unification, even if this class didn't work out.
8095 We also don't want to commit ourselves to all the unifications
8096 we've already done, since unification is supposed to be done on
8097 an argument-by-argument basis. In other words, consider the
8098 following pathological case:
8099
8100 template <int I, int J, int K>
8101 struct S {};
8102
8103 template <int I, int J>
8104 struct S<I, J, 2> : public S<I, I, I>, S<J, J, J> {};
8105
8106 template <int I, int J, int K>
8107 void f(S<I, J, K>, S<I, I, I>);
8108
8109 void g() {
8110 S<0, 0, 0> s0;
8111 S<0, 1, 2> s2;
8112
8113 f(s0, s2);
8114 }
8115
8116 Now, by the time we consider the unification involving `s2', we
8117 already know that we must have `f<0, 0, 0>'. But, even though
8118 `S<0, 1, 2>' is derived from `S<0, 0, 0>', the code is not legal
8119 because there are two ways to unify base classes of S<0, 1, 2>
8120 with S<I, I, I>. If we kept the already deduced knowledge, we
8121 would reject the possibility I=1. */
8122 copy_of_targs = make_tree_vec (TREE_VEC_LENGTH (targs));
8123 i = unify (tparms, copy_of_targs, CLASSTYPE_TI_ARGS (parm),
8124 CLASSTYPE_TI_ARGS (arg), UNIFY_ALLOW_NONE);
8125
8126 /* If unification failed, we're done. */
8127 if (i != 0)
8128 return NULL_TREE;
8129 else
8130 return arg;
8131 }
8132
8133 /* Subroutine of get_template_base. RVAL, if non-NULL, is a base we
8134 have alreay discovered to be satisfactory. ARG_BINFO is the binfo
8135 for the base class of ARG that we are currently examining. */
8136
8137 static tree
8138 get_template_base_recursive (tparms, targs, parm,
8139 arg_binfo, rval, flags)
8140 tree tparms;
8141 tree targs;
8142 tree arg_binfo;
8143 tree rval;
8144 tree parm;
8145 int flags;
8146 {
8147 tree binfos;
8148 int i, n_baselinks;
8149 tree arg = BINFO_TYPE (arg_binfo);
8150
8151 if (!(flags & GTB_IGNORE_TYPE))
8152 {
8153 tree r = try_class_unification (tparms, targs,
8154 parm, arg);
8155
8156 /* If there is more than one satisfactory baseclass, then:
8157
8158 [temp.deduct.call]
8159
8160 If they yield more than one possible deduced A, the type
8161 deduction fails.
8162
8163 applies. */
8164 if (r && rval && !same_type_p (r, rval))
8165 return error_mark_node;
8166 else if (r)
8167 rval = r;
8168 }
8169
8170 binfos = BINFO_BASETYPES (arg_binfo);
8171 n_baselinks = binfos ? TREE_VEC_LENGTH (binfos) : 0;
8172
8173 /* Process base types. */
8174 for (i = 0; i < n_baselinks; i++)
8175 {
8176 tree base_binfo = TREE_VEC_ELT (binfos, i);
8177 int this_virtual;
8178
8179 /* Skip this base, if we've already seen it. */
8180 if (BINFO_MARKED (base_binfo))
8181 continue;
8182
8183 this_virtual =
8184 (flags & GTB_VIA_VIRTUAL) || TREE_VIA_VIRTUAL (base_binfo);
8185
8186 /* When searching for a non-virtual, we cannot mark virtually
8187 found binfos. */
8188 if (! this_virtual)
8189 SET_BINFO_MARKED (base_binfo);
8190
8191 rval = get_template_base_recursive (tparms, targs,
8192 parm,
8193 base_binfo,
8194 rval,
8195 GTB_VIA_VIRTUAL * this_virtual);
8196
8197 /* If we discovered more than one matching base class, we can
8198 stop now. */
8199 if (rval == error_mark_node)
8200 return error_mark_node;
8201 }
8202
8203 return rval;
8204 }
8205
8206 /* Given a template type PARM and a class type ARG, find the unique
8207 base type in ARG that is an instance of PARM. We do not examine
8208 ARG itself; only its base-classes. If there is no appropriate base
8209 class, return NULL_TREE. If there is more than one, return
8210 error_mark_node. PARM may be the type of a partial specialization,
8211 as well as a plain template type. Used by unify. */
8212
8213 static tree
8214 get_template_base (tparms, targs, parm, arg)
8215 tree tparms;
8216 tree targs;
8217 tree parm;
8218 tree arg;
8219 {
8220 tree rval;
8221 tree arg_binfo;
8222
8223 my_friendly_assert (IS_AGGR_TYPE_CODE (TREE_CODE (arg)), 92);
8224
8225 arg_binfo = TYPE_BINFO (complete_type (arg));
8226 rval = get_template_base_recursive (tparms, targs,
8227 parm, arg_binfo,
8228 NULL_TREE,
8229 GTB_IGNORE_TYPE);
8230
8231 /* Since get_template_base_recursive marks the bases classes, we
8232 must unmark them here. */
8233 dfs_walk (arg_binfo, dfs_unmark, markedp, 0);
8234
8235 return rval;
8236 }
8237
8238 /* Returns the level of DECL, which declares a template parameter. */
8239
8240 static int
8241 template_decl_level (decl)
8242 tree decl;
8243 {
8244 switch (TREE_CODE (decl))
8245 {
8246 case TYPE_DECL:
8247 case TEMPLATE_DECL:
8248 return TEMPLATE_TYPE_LEVEL (TREE_TYPE (decl));
8249
8250 case PARM_DECL:
8251 return TEMPLATE_PARM_LEVEL (DECL_INITIAL (decl));
8252
8253 default:
8254 my_friendly_abort (0);
8255 return 0;
8256 }
8257 }
8258
8259 /* Decide whether ARG can be unified with PARM, considering only the
8260 cv-qualifiers of each type, given STRICT as documented for unify.
8261 Returns non-zero iff the unification is OK on that basis.*/
8262
8263 static int
8264 check_cv_quals_for_unify (strict, arg, parm)
8265 int strict;
8266 tree arg;
8267 tree parm;
8268 {
8269 if (!(strict & UNIFY_ALLOW_MORE_CV_QUAL)
8270 && !at_least_as_qualified_p (arg, parm))
8271 return 0;
8272
8273 if (!(strict & UNIFY_ALLOW_LESS_CV_QUAL)
8274 && !at_least_as_qualified_p (parm, arg))
8275 return 0;
8276
8277 return 1;
8278 }
8279
8280 /* Takes parameters as for type_unification. Returns 0 if the
8281 type deduction suceeds, 1 otherwise. The parameter STRICT is a
8282 bitwise or of the following flags:
8283
8284 UNIFY_ALLOW_NONE:
8285 Require an exact match between PARM and ARG.
8286 UNIFY_ALLOW_MORE_CV_QUAL:
8287 Allow the deduced ARG to be more cv-qualified than ARG.
8288 UNIFY_ALLOW_LESS_CV_QUAL:
8289 Allow the deduced ARG to be less cv-qualified than ARG.
8290 UNIFY_ALLOW_DERIVED:
8291 Allow the deduced ARG to be a template base class of ARG,
8292 or a pointer to a template base class of the type pointed to by
8293 ARG.
8294 UNIFY_ALLOW_INTEGER:
8295 Allow any integral type to be deduced. See the TEMPLATE_PARM_INDEX
8296 case for more information. */
8297
8298 static int
8299 unify (tparms, targs, parm, arg, strict)
8300 tree tparms, targs, parm, arg;
8301 int strict;
8302 {
8303 int idx;
8304 tree targ;
8305 tree tparm;
8306
8307 /* I don't think this will do the right thing with respect to types.
8308 But the only case I've seen it in so far has been array bounds, where
8309 signedness is the only information lost, and I think that will be
8310 okay. */
8311 while (TREE_CODE (parm) == NOP_EXPR)
8312 parm = TREE_OPERAND (parm, 0);
8313
8314 if (arg == error_mark_node)
8315 return 1;
8316 if (arg == unknown_type_node)
8317 /* We can't deduce anything from this, but we might get all the
8318 template args from other function args. */
8319 return 0;
8320
8321 /* If PARM uses template parameters, then we can't bail out here,
8322 even if ARG == PARM, since we won't record unifications for the
8323 template parameters. We might need them if we're trying to
8324 figure out which of two things is more specialized. */
8325 if (arg == parm && !uses_template_parms (parm))
8326 return 0;
8327
8328 /* Immediately reject some pairs that won't unify because of
8329 cv-qualification mismatches. */
8330 if (TREE_CODE (arg) == TREE_CODE (parm)
8331 && TYPE_P (arg)
8332 /* We check the cv-qualifiers when unifying with template type
8333 parameters below. We want to allow ARG `const T' to unify with
8334 PARM `T' for example, when computing which of two templates
8335 is more specialized, for example. */
8336 && TREE_CODE (arg) != TEMPLATE_TYPE_PARM
8337 && !check_cv_quals_for_unify (strict, arg, parm))
8338 return 1;
8339
8340 switch (TREE_CODE (parm))
8341 {
8342 case TYPENAME_TYPE:
8343 /* In a type which contains a nested-name-specifier, template
8344 argument values cannot be deduced for template parameters used
8345 within the nested-name-specifier. */
8346 return 0;
8347
8348 case TEMPLATE_TYPE_PARM:
8349 case TEMPLATE_TEMPLATE_PARM:
8350 tparm = TREE_VALUE (TREE_VEC_ELT (tparms, 0));
8351
8352 if (TEMPLATE_TYPE_LEVEL (parm)
8353 != template_decl_level (tparm))
8354 /* The PARM is not one we're trying to unify. Just check
8355 to see if it matches ARG. */
8356 return (TREE_CODE (arg) == TREE_CODE (parm)
8357 && same_type_p (parm, arg)) ? 0 : 1;
8358 idx = TEMPLATE_TYPE_IDX (parm);
8359 targ = TREE_VEC_ELT (targs, idx);
8360 tparm = TREE_VALUE (TREE_VEC_ELT (tparms, idx));
8361
8362 /* Check for mixed types and values. */
8363 if ((TREE_CODE (parm) == TEMPLATE_TYPE_PARM
8364 && TREE_CODE (tparm) != TYPE_DECL)
8365 || (TREE_CODE (parm) == TEMPLATE_TEMPLATE_PARM
8366 && TREE_CODE (tparm) != TEMPLATE_DECL))
8367 return 1;
8368
8369 if (TREE_CODE (parm) == TEMPLATE_TEMPLATE_PARM)
8370 {
8371 if (TEMPLATE_TEMPLATE_PARM_TEMPLATE_INFO (parm))
8372 {
8373 /* We arrive here when PARM does not involve template
8374 specialization. */
8375
8376 /* ARG must be constructed from a template class. */
8377 if (TREE_CODE (arg) != RECORD_TYPE || !CLASSTYPE_TEMPLATE_INFO (arg))
8378 return 1;
8379
8380 {
8381 tree parmtmpl = TYPE_TI_TEMPLATE (parm);
8382 tree parmvec = TYPE_TI_ARGS (parm);
8383 tree argvec = CLASSTYPE_TI_ARGS (arg);
8384 tree argtmplvec
8385 = DECL_INNERMOST_TEMPLATE_PARMS (CLASSTYPE_TI_TEMPLATE (arg));
8386 int i;
8387
8388 /* The parameter and argument roles have to be switched here
8389 in order to handle default arguments properly. For example,
8390 template<template <class> class TT> void f(TT<int>)
8391 should be able to accept vector<int> which comes from
8392 template <class T, class Allocator = allocator>
8393 class vector. */
8394
8395 if (coerce_template_parms (argtmplvec, parmvec, parmtmpl, 0, 1)
8396 == error_mark_node)
8397 return 1;
8398
8399 /* Deduce arguments T, i from TT<T> or TT<i>.
8400 We check each element of PARMVEC and ARGVEC individually
8401 rather than the whole TREE_VEC since they can have
8402 different number of elements. */
8403
8404 for (i = 0; i < TREE_VEC_LENGTH (parmvec); ++i)
8405 {
8406 tree t = TREE_VEC_ELT (parmvec, i);
8407
8408 if (unify (tparms, targs, t,
8409 TREE_VEC_ELT (argvec, i),
8410 UNIFY_ALLOW_NONE))
8411 return 1;
8412 }
8413 }
8414 arg = CLASSTYPE_TI_TEMPLATE (arg);
8415 }
8416 }
8417 else
8418 {
8419 /* If PARM is `const T' and ARG is only `int', we don't have
8420 a match unless we are allowing additional qualification.
8421 If ARG is `const int' and PARM is just `T' that's OK;
8422 that binds `const int' to `T'. */
8423 if (!check_cv_quals_for_unify (strict | UNIFY_ALLOW_LESS_CV_QUAL,
8424 arg, parm))
8425 return 1;
8426
8427 /* Consider the case where ARG is `const volatile int' and
8428 PARM is `const T'. Then, T should be `volatile int'. */
8429 arg =
8430 cp_build_qualified_type_real (arg,
8431 CP_TYPE_QUALS (arg)
8432 & ~CP_TYPE_QUALS (parm),
8433 /*complain=*/0);
8434 if (arg == error_mark_node)
8435 return 1;
8436 }
8437
8438 /* Simple cases: Value already set, does match or doesn't. */
8439 if (targ != NULL_TREE && same_type_p (targ, arg))
8440 return 0;
8441 else if (targ)
8442 return 1;
8443
8444 /* Make sure that ARG is not a variable-sized array. (Note that
8445 were talking about variable-sized arrays (like `int[n]'),
8446 rather than arrays of unknown size (like `int[]').) We'll
8447 get very confused by such a type since the bound of the array
8448 will not be computable in an instantiation. Besides, such
8449 types are not allowed in ISO C++, so we can do as we please
8450 here. */
8451 if (TREE_CODE (arg) == ARRAY_TYPE
8452 && !uses_template_parms (arg)
8453 && (TREE_CODE (TYPE_MAX_VALUE (TYPE_DOMAIN (arg)))
8454 != INTEGER_CST))
8455 return 1;
8456
8457 TREE_VEC_ELT (targs, idx) = arg;
8458 return 0;
8459
8460 case TEMPLATE_PARM_INDEX:
8461 tparm = TREE_VALUE (TREE_VEC_ELT (tparms, 0));
8462
8463 if (TEMPLATE_PARM_LEVEL (parm)
8464 != template_decl_level (tparm))
8465 /* The PARM is not one we're trying to unify. Just check
8466 to see if it matches ARG. */
8467 return (TREE_CODE (arg) == TREE_CODE (parm)
8468 && cp_tree_equal (parm, arg) > 0) ? 0 : 1;
8469
8470 idx = TEMPLATE_PARM_IDX (parm);
8471 targ = TREE_VEC_ELT (targs, idx);
8472
8473 if (targ)
8474 {
8475 int i = (cp_tree_equal (targ, arg) > 0);
8476 if (i == 1)
8477 return 0;
8478 else if (i == 0)
8479 return 1;
8480 else
8481 my_friendly_abort (42);
8482 }
8483
8484 /* [temp.deduct.type] If, in the declaration of a function template
8485 with a non-type template-parameter, the non-type
8486 template-parameter is used in an expression in the function
8487 parameter-list and, if the corresponding template-argument is
8488 deduced, the template-argument type shall match the type of the
8489 template-parameter exactly, except that a template-argument
8490 deduced from an array bound may be of any integral type. */
8491 if (same_type_p (TREE_TYPE (arg), TREE_TYPE (parm)))
8492 /* OK */;
8493 else if ((strict & UNIFY_ALLOW_INTEGER)
8494 && (TREE_CODE (TREE_TYPE (parm)) == INTEGER_TYPE
8495 || TREE_CODE (TREE_TYPE (parm)) == BOOLEAN_TYPE))
8496 /* OK */;
8497 else
8498 return 1;
8499
8500 TREE_VEC_ELT (targs, idx) = arg;
8501 return 0;
8502
8503 case POINTER_TYPE:
8504 {
8505 int sub_strict;
8506
8507 if (TREE_CODE (arg) != POINTER_TYPE)
8508 return 1;
8509
8510 /* [temp.deduct.call]
8511
8512 A can be another pointer or pointer to member type that can
8513 be converted to the deduced A via a qualification
8514 conversion (_conv.qual_).
8515
8516 We pass down STRICT here rather than UNIFY_ALLOW_NONE.
8517 This will allow for additional cv-qualification of the
8518 pointed-to types if appropriate. In general, this is a bit
8519 too generous; we are only supposed to allow qualification
8520 conversions and this method will allow an ARG of char** and
8521 a deduced ARG of const char**. However, overload
8522 resolution will subsequently invalidate the candidate, so
8523 this is probably OK. */
8524 sub_strict = strict;
8525
8526 if (TREE_CODE (TREE_TYPE (arg)) != RECORD_TYPE)
8527 /* The derived-to-base conversion only persists through one
8528 level of pointers. */
8529 sub_strict &= ~UNIFY_ALLOW_DERIVED;
8530
8531 return unify (tparms, targs, TREE_TYPE (parm),
8532 TREE_TYPE (arg), sub_strict);
8533 }
8534
8535 case REFERENCE_TYPE:
8536 if (TREE_CODE (arg) != REFERENCE_TYPE)
8537 return 1;
8538 return unify (tparms, targs, TREE_TYPE (parm), TREE_TYPE (arg),
8539 UNIFY_ALLOW_NONE);
8540
8541 case ARRAY_TYPE:
8542 if (TREE_CODE (arg) != ARRAY_TYPE)
8543 return 1;
8544 if ((TYPE_DOMAIN (parm) == NULL_TREE)
8545 != (TYPE_DOMAIN (arg) == NULL_TREE))
8546 return 1;
8547 if (TYPE_DOMAIN (parm) != NULL_TREE
8548 && unify (tparms, targs, TYPE_DOMAIN (parm),
8549 TYPE_DOMAIN (arg), UNIFY_ALLOW_NONE) != 0)
8550 return 1;
8551 return unify (tparms, targs, TREE_TYPE (parm), TREE_TYPE (arg),
8552 UNIFY_ALLOW_NONE);
8553
8554 case REAL_TYPE:
8555 case COMPLEX_TYPE:
8556 case INTEGER_TYPE:
8557 case BOOLEAN_TYPE:
8558 case VOID_TYPE:
8559 if (TREE_CODE (arg) != TREE_CODE (parm))
8560 return 1;
8561
8562 if (TREE_CODE (parm) == INTEGER_TYPE
8563 && TREE_CODE (TYPE_MAX_VALUE (parm)) != INTEGER_CST)
8564 {
8565 if (TYPE_MIN_VALUE (parm) && TYPE_MIN_VALUE (arg)
8566 && unify (tparms, targs, TYPE_MIN_VALUE (parm),
8567 TYPE_MIN_VALUE (arg), UNIFY_ALLOW_INTEGER))
8568 return 1;
8569 if (TYPE_MAX_VALUE (parm) && TYPE_MAX_VALUE (arg)
8570 && unify (tparms, targs, TYPE_MAX_VALUE (parm),
8571 TYPE_MAX_VALUE (arg), UNIFY_ALLOW_INTEGER))
8572 return 1;
8573 }
8574 /* We have already checked cv-qualification at the top of the
8575 function. */
8576 else if (!same_type_ignoring_top_level_qualifiers_p (arg, parm))
8577 return 1;
8578
8579 /* As far as unification is concerned, this wins. Later checks
8580 will invalidate it if necessary. */
8581 return 0;
8582
8583 /* Types INTEGER_CST and MINUS_EXPR can come from array bounds. */
8584 /* Type INTEGER_CST can come from ordinary constant template args. */
8585 case INTEGER_CST:
8586 while (TREE_CODE (arg) == NOP_EXPR)
8587 arg = TREE_OPERAND (arg, 0);
8588
8589 if (TREE_CODE (arg) != INTEGER_CST)
8590 return 1;
8591 return !tree_int_cst_equal (parm, arg);
8592
8593 case TREE_VEC:
8594 {
8595 int i;
8596 if (TREE_CODE (arg) != TREE_VEC)
8597 return 1;
8598 if (TREE_VEC_LENGTH (parm) != TREE_VEC_LENGTH (arg))
8599 return 1;
8600 for (i = 0; i < TREE_VEC_LENGTH (parm); ++i)
8601 if (unify (tparms, targs,
8602 TREE_VEC_ELT (parm, i), TREE_VEC_ELT (arg, i),
8603 UNIFY_ALLOW_NONE))
8604 return 1;
8605 return 0;
8606 }
8607
8608 case RECORD_TYPE:
8609 case UNION_TYPE:
8610 if (TREE_CODE (arg) != TREE_CODE (parm))
8611 return 1;
8612
8613 if (TYPE_PTRMEMFUNC_P (parm))
8614 {
8615 if (!TYPE_PTRMEMFUNC_P (arg))
8616 return 1;
8617
8618 return unify (tparms, targs,
8619 TYPE_PTRMEMFUNC_FN_TYPE (parm),
8620 TYPE_PTRMEMFUNC_FN_TYPE (arg),
8621 strict);
8622 }
8623
8624 if (CLASSTYPE_TEMPLATE_INFO (parm))
8625 {
8626 tree t = NULL_TREE;
8627
8628 if (strict & UNIFY_ALLOW_DERIVED)
8629 {
8630 /* First, we try to unify the PARM and ARG directly. */
8631 t = try_class_unification (tparms, targs,
8632 parm, arg);
8633
8634 if (!t)
8635 {
8636 /* Fallback to the special case allowed in
8637 [temp.deduct.call]:
8638
8639 If P is a class, and P has the form
8640 template-id, then A can be a derived class of
8641 the deduced A. Likewise, if P is a pointer to
8642 a class of the form template-id, A can be a
8643 pointer to a derived class pointed to by the
8644 deduced A. */
8645 t = get_template_base (tparms, targs,
8646 parm, arg);
8647
8648 if (! t || t == error_mark_node)
8649 return 1;
8650 }
8651 }
8652 else if (CLASSTYPE_TEMPLATE_INFO (arg)
8653 && (CLASSTYPE_TI_TEMPLATE (parm)
8654 == CLASSTYPE_TI_TEMPLATE (arg)))
8655 /* Perhaps PARM is something like S<U> and ARG is S<int>.
8656 Then, we should unify `int' and `U'. */
8657 t = arg;
8658 else
8659 /* There's no chance of unication succeeding. */
8660 return 1;
8661
8662 return unify (tparms, targs, CLASSTYPE_TI_ARGS (parm),
8663 CLASSTYPE_TI_ARGS (t), UNIFY_ALLOW_NONE);
8664 }
8665 else if (!same_type_ignoring_top_level_qualifiers_p (parm, arg))
8666 return 1;
8667 return 0;
8668
8669 case METHOD_TYPE:
8670 case FUNCTION_TYPE:
8671 if (TREE_CODE (arg) != TREE_CODE (parm))
8672 return 1;
8673
8674 if (unify (tparms, targs, TREE_TYPE (parm),
8675 TREE_TYPE (arg), UNIFY_ALLOW_NONE))
8676 return 1;
8677 return type_unification_real (tparms, targs, TYPE_ARG_TYPES (parm),
8678 TYPE_ARG_TYPES (arg), 1,
8679 DEDUCE_EXACT, 0);
8680
8681 case OFFSET_TYPE:
8682 if (TREE_CODE (arg) != OFFSET_TYPE)
8683 return 1;
8684 if (unify (tparms, targs, TYPE_OFFSET_BASETYPE (parm),
8685 TYPE_OFFSET_BASETYPE (arg), UNIFY_ALLOW_NONE))
8686 return 1;
8687 return unify (tparms, targs, TREE_TYPE (parm), TREE_TYPE (arg),
8688 strict);
8689
8690 case CONST_DECL:
8691 if (arg != decl_constant_value (parm))
8692 return 1;
8693 return 0;
8694
8695 case TEMPLATE_DECL:
8696 /* Matched cases are handled by the ARG == PARM test above. */
8697 return 1;
8698
8699 case MINUS_EXPR:
8700 if (TREE_CODE (TREE_OPERAND (parm, 1)) == INTEGER_CST)
8701 {
8702 /* We handle this case specially, since it comes up with
8703 arrays. In particular, something like:
8704
8705 template <int N> void f(int (&x)[N]);
8706
8707 Here, we are trying to unify the range type, which
8708 looks like [0 ... (N - 1)]. */
8709 tree t, t1, t2;
8710 t1 = TREE_OPERAND (parm, 0);
8711 t2 = TREE_OPERAND (parm, 1);
8712
8713 t = fold (build (PLUS_EXPR, integer_type_node, arg, t2));
8714
8715 return unify (tparms, targs, t1, t, strict);
8716 }
8717 /* else fall through */
8718
8719 default:
8720 if (IS_EXPR_CODE_CLASS (TREE_CODE_CLASS (TREE_CODE (parm))))
8721 /* We're looking at an expression. This can happen with
8722 something like:
8723
8724 template <int I>
8725 void foo(S<I>, S<I + 2>);
8726
8727 This is a "nondeduced context":
8728
8729 [deduct.type]
8730
8731 The nondeduced contexts are:
8732
8733 --A type that is a template-id in which one or more of
8734 the template-arguments is an expression that references
8735 a template-parameter.
8736
8737 In these cases, we assume deduction succeeded, but don't
8738 actually infer any unifications. */
8739 return 0;
8740 else
8741 sorry ("use of `%s' in template type unification",
8742 tree_code_name [(int) TREE_CODE (parm)]);
8743
8744 return 1;
8745 }
8746 }
8747 \f
8748 /* Called if RESULT is explicitly instantiated, or is a member of an
8749 explicitly instantiated class, or if using -frepo and the
8750 instantiation of RESULT has been assigned to this file. */
8751
8752 void
8753 mark_decl_instantiated (result, extern_p)
8754 tree result;
8755 int extern_p;
8756 {
8757 if (TREE_CODE (result) != FUNCTION_DECL)
8758 /* The TREE_PUBLIC flag for function declarations will have been
8759 set correctly by tsubst. */
8760 TREE_PUBLIC (result) = 1;
8761
8762 /* We used to set this unconditionally; we moved that to
8763 do_decl_instantiation so it wouldn't get set on members of
8764 explicit class template instantiations. But we still need to set
8765 it here for the 'extern template' case in order to suppress
8766 implicit instantiations. */
8767 if (extern_p)
8768 SET_DECL_EXPLICIT_INSTANTIATION (result);
8769
8770 if (! extern_p)
8771 {
8772 DECL_INTERFACE_KNOWN (result) = 1;
8773 DECL_NOT_REALLY_EXTERN (result) = 1;
8774
8775 /* Always make artificials weak. */
8776 if (DECL_ARTIFICIAL (result) && flag_weak)
8777 comdat_linkage (result);
8778 /* For WIN32 we also want to put explicit instantiations in
8779 linkonce sections. */
8780 else if (TREE_PUBLIC (result))
8781 maybe_make_one_only (result);
8782 }
8783 else if (TREE_CODE (result) == FUNCTION_DECL)
8784 defer_fn (result);
8785 }
8786
8787 /* Given two function templates PAT1 and PAT2, and explicit template
8788 arguments EXPLICIT_ARGS return:
8789
8790 1 if PAT1 is more specialized than PAT2 as described in [temp.func.order].
8791 -1 if PAT2 is more specialized than PAT1.
8792 0 if neither is more specialized. */
8793
8794 int
8795 more_specialized (pat1, pat2, explicit_args)
8796 tree pat1, pat2, explicit_args;
8797 {
8798 tree targs;
8799 int winner = 0;
8800
8801 targs
8802 = get_bindings_overload (pat1, DECL_TEMPLATE_RESULT (pat2), explicit_args);
8803 if (targs)
8804 --winner;
8805
8806 targs
8807 = get_bindings_overload (pat2, DECL_TEMPLATE_RESULT (pat1), explicit_args);
8808 if (targs)
8809 ++winner;
8810
8811 return winner;
8812 }
8813
8814 /* Given two class template specialization list nodes PAT1 and PAT2, return:
8815
8816 1 if PAT1 is more specialized than PAT2 as described in [temp.class.order].
8817 -1 if PAT2 is more specialized than PAT1.
8818 0 if neither is more specialized. */
8819
8820 int
8821 more_specialized_class (pat1, pat2)
8822 tree pat1, pat2;
8823 {
8824 tree targs;
8825 int winner = 0;
8826
8827 targs = get_class_bindings (TREE_VALUE (pat1), TREE_PURPOSE (pat1),
8828 TREE_PURPOSE (pat2));
8829 if (targs)
8830 --winner;
8831
8832 targs = get_class_bindings (TREE_VALUE (pat2), TREE_PURPOSE (pat2),
8833 TREE_PURPOSE (pat1));
8834 if (targs)
8835 ++winner;
8836
8837 return winner;
8838 }
8839
8840 /* Return the template arguments that will produce the function signature
8841 DECL from the function template FN, with the explicit template
8842 arguments EXPLICIT_ARGS. If CHECK_RETTYPE is 1, the return type must
8843 also match. Return NULL_TREE if no satisfactory arguments could be
8844 found. */
8845
8846 static tree
8847 get_bindings_real (fn, decl, explicit_args, check_rettype)
8848 tree fn, decl, explicit_args;
8849 int check_rettype;
8850 {
8851 int ntparms = DECL_NTPARMS (fn);
8852 tree targs = make_tree_vec (ntparms);
8853 tree decl_type;
8854 tree decl_arg_types;
8855 int i;
8856
8857 /* Substitute the explicit template arguments into the type of DECL.
8858 The call to fn_type_unification will handle substitution into the
8859 FN. */
8860 decl_type = TREE_TYPE (decl);
8861 if (explicit_args && uses_template_parms (decl_type))
8862 {
8863 tree tmpl;
8864 tree converted_args;
8865
8866 if (DECL_TEMPLATE_INFO (decl))
8867 tmpl = DECL_TI_TEMPLATE (decl);
8868 else
8869 /* We can get here for some illegal specializations. */
8870 return NULL_TREE;
8871
8872 converted_args
8873 = (coerce_template_parms (DECL_INNERMOST_TEMPLATE_PARMS (tmpl),
8874 explicit_args, NULL_TREE,
8875 /*complain=*/0,
8876 /*require_all_arguments=*/0));
8877 if (converted_args == error_mark_node)
8878 return NULL_TREE;
8879
8880 decl_type = tsubst (decl_type, converted_args, /*complain=*/0,
8881 NULL_TREE);
8882 if (decl_type == error_mark_node)
8883 return NULL_TREE;
8884 }
8885
8886 /* If FN is a static member function, adjust the type of DECL
8887 appropriately. */
8888 decl_arg_types = TYPE_ARG_TYPES (decl_type);
8889 if (DECL_STATIC_FUNCTION_P (fn)
8890 && DECL_NONSTATIC_MEMBER_FUNCTION_P (decl))
8891 decl_arg_types = TREE_CHAIN (decl_arg_types);
8892
8893 i = fn_type_unification (fn, explicit_args, targs,
8894 decl_arg_types,
8895 (check_rettype || DECL_CONV_FN_P (fn)
8896 ? TREE_TYPE (decl_type) : NULL_TREE),
8897 DEDUCE_EXACT);
8898
8899 if (i != 0)
8900 return NULL_TREE;
8901
8902 return targs;
8903 }
8904
8905 /* For most uses, we want to check the return type. */
8906
8907 tree
8908 get_bindings (fn, decl, explicit_args)
8909 tree fn, decl, explicit_args;
8910 {
8911 return get_bindings_real (fn, decl, explicit_args, 1);
8912 }
8913
8914 /* But for more_specialized, we only care about the parameter types. */
8915
8916 static tree
8917 get_bindings_overload (fn, decl, explicit_args)
8918 tree fn, decl, explicit_args;
8919 {
8920 return get_bindings_real (fn, decl, explicit_args, 0);
8921 }
8922
8923 /* Return the innermost template arguments that, when applied to a
8924 template specialization whose innermost template parameters are
8925 TPARMS, and whose specialization arguments are ARGS, yield the
8926 ARGS.
8927
8928 For example, suppose we have:
8929
8930 template <class T, class U> struct S {};
8931 template <class T> struct S<T*, int> {};
8932
8933 Then, suppose we want to get `S<double*, int>'. The TPARMS will be
8934 {T}, the PARMS will be {T*, int} and the ARGS will be {double*,
8935 int}. The resulting vector will be {double}, indicating that `T'
8936 is bound to `double'. */
8937
8938 static tree
8939 get_class_bindings (tparms, parms, args)
8940 tree tparms, parms, args;
8941 {
8942 int i, ntparms = TREE_VEC_LENGTH (tparms);
8943 tree vec = make_tree_vec (ntparms);
8944
8945 args = INNERMOST_TEMPLATE_ARGS (args);
8946
8947 if (unify (tparms, vec, parms, args, UNIFY_ALLOW_NONE))
8948 return NULL_TREE;
8949
8950 for (i = 0; i < ntparms; ++i)
8951 if (! TREE_VEC_ELT (vec, i))
8952 return NULL_TREE;
8953
8954 return vec;
8955 }
8956
8957 /* In INSTANTIATIONS is a list of <INSTANTIATION, TEMPLATE> pairs.
8958 Pick the most specialized template, and return the corresponding
8959 instantiation, or if there is no corresponding instantiation, the
8960 template itself. EXPLICIT_ARGS is any template arguments explicity
8961 mentioned in a template-id. If there is no most specialized
8962 template, error_mark_node is returned. If there are no templates
8963 at all, NULL_TREE is returned. */
8964
8965 tree
8966 most_specialized_instantiation (instantiations, explicit_args)
8967 tree instantiations;
8968 tree explicit_args;
8969 {
8970 tree fn, champ;
8971 int fate;
8972
8973 if (!instantiations)
8974 return NULL_TREE;
8975
8976 champ = instantiations;
8977 for (fn = TREE_CHAIN (instantiations); fn; fn = TREE_CHAIN (fn))
8978 {
8979 fate = more_specialized (TREE_VALUE (champ),
8980 TREE_VALUE (fn), explicit_args);
8981 if (fate == 1)
8982 ;
8983 else
8984 {
8985 if (fate == 0)
8986 {
8987 fn = TREE_CHAIN (fn);
8988 if (! fn)
8989 return error_mark_node;
8990 }
8991 champ = fn;
8992 }
8993 }
8994
8995 for (fn = instantiations; fn && fn != champ; fn = TREE_CHAIN (fn))
8996 {
8997 fate = more_specialized (TREE_VALUE (champ),
8998 TREE_VALUE (fn), explicit_args);
8999 if (fate != 1)
9000 return error_mark_node;
9001 }
9002
9003 return TREE_PURPOSE (champ) ? TREE_PURPOSE (champ) : TREE_VALUE (champ);
9004 }
9005
9006 /* Return the most specialized of the list of templates in FNS that can
9007 produce an instantiation matching DECL, given the explicit template
9008 arguments EXPLICIT_ARGS. */
9009
9010 static tree
9011 most_specialized (fns, decl, explicit_args)
9012 tree fns, decl, explicit_args;
9013 {
9014 tree candidates = NULL_TREE;
9015 tree fn, args;
9016
9017 for (fn = fns; fn; fn = TREE_CHAIN (fn))
9018 {
9019 tree candidate = TREE_VALUE (fn);
9020
9021 args = get_bindings (candidate, decl, explicit_args);
9022 if (args)
9023 candidates = tree_cons (NULL_TREE, candidate, candidates);
9024 }
9025
9026 return most_specialized_instantiation (candidates, explicit_args);
9027 }
9028
9029 /* If DECL is a specialization of some template, return the most
9030 general such template. Otherwise, returns NULL_TREE.
9031
9032 For example, given:
9033
9034 template <class T> struct S { template <class U> void f(U); };
9035
9036 if TMPL is `template <class U> void S<int>::f(U)' this will return
9037 the full template. This function will not trace past partial
9038 specializations, however. For example, given in addition:
9039
9040 template <class T> struct S<T*> { template <class U> void f(U); };
9041
9042 if TMPL is `template <class U> void S<int*>::f(U)' this will return
9043 `template <class T> template <class U> S<T*>::f(U)'. */
9044
9045 tree
9046 most_general_template (decl)
9047 tree decl;
9048 {
9049 /* If DECL is a FUNCTION_DECL, find the TEMPLATE_DECL of which it is
9050 an immediate specialization. */
9051 if (TREE_CODE (decl) == FUNCTION_DECL)
9052 {
9053 if (DECL_TEMPLATE_INFO (decl)) {
9054 decl = DECL_TI_TEMPLATE (decl);
9055
9056 /* The DECL_TI_TEMPLATE can be an IDENTIFIER_NODE for a
9057 template friend. */
9058 if (TREE_CODE (decl) != TEMPLATE_DECL)
9059 return NULL_TREE;
9060 } else
9061 return NULL_TREE;
9062 }
9063
9064 /* Look for more and more general templates. */
9065 while (DECL_TEMPLATE_INFO (decl))
9066 {
9067 /* The DECL_TI_TEMPLATE can be a LOOKUP_EXPR or IDENTIFIER_NODE
9068 in some cases. (See cp-tree.h for details.) */
9069 if (TREE_CODE (DECL_TI_TEMPLATE (decl)) != TEMPLATE_DECL)
9070 break;
9071
9072 /* Stop if we run into an explicitly specialized class template. */
9073 if (!DECL_NAMESPACE_SCOPE_P (decl)
9074 && DECL_CONTEXT (decl)
9075 && CLASSTYPE_TEMPLATE_SPECIALIZATION (DECL_CONTEXT (decl)))
9076 break;
9077
9078 decl = DECL_TI_TEMPLATE (decl);
9079 }
9080
9081 return decl;
9082 }
9083
9084 /* Return the most specialized of the class template specializations
9085 of TMPL which can produce an instantiation matching ARGS, or
9086 error_mark_node if the choice is ambiguous. */
9087
9088 static tree
9089 most_specialized_class (tmpl, args)
9090 tree tmpl;
9091 tree args;
9092 {
9093 tree list = NULL_TREE;
9094 tree t;
9095 tree champ;
9096 int fate;
9097
9098 tmpl = most_general_template (tmpl);
9099 for (t = DECL_TEMPLATE_SPECIALIZATIONS (tmpl); t; t = TREE_CHAIN (t))
9100 {
9101 tree spec_args
9102 = get_class_bindings (TREE_VALUE (t), TREE_PURPOSE (t), args);
9103 if (spec_args)
9104 {
9105 list = decl_tree_cons (TREE_PURPOSE (t), TREE_VALUE (t), list);
9106 TREE_TYPE (list) = TREE_TYPE (t);
9107 }
9108 }
9109
9110 if (! list)
9111 return NULL_TREE;
9112
9113 t = list;
9114 champ = t;
9115 t = TREE_CHAIN (t);
9116 for (; t; t = TREE_CHAIN (t))
9117 {
9118 fate = more_specialized_class (champ, t);
9119 if (fate == 1)
9120 ;
9121 else
9122 {
9123 if (fate == 0)
9124 {
9125 t = TREE_CHAIN (t);
9126 if (! t)
9127 return error_mark_node;
9128 }
9129 champ = t;
9130 }
9131 }
9132
9133 for (t = list; t && t != champ; t = TREE_CHAIN (t))
9134 {
9135 fate = more_specialized_class (champ, t);
9136 if (fate != 1)
9137 return error_mark_node;
9138 }
9139
9140 return champ;
9141 }
9142
9143 /* called from the parser. */
9144
9145 void
9146 do_decl_instantiation (declspecs, declarator, storage)
9147 tree declspecs, declarator, storage;
9148 {
9149 tree decl = grokdeclarator (declarator, declspecs, NORMAL, 0, NULL_TREE);
9150 tree result = NULL_TREE;
9151 int extern_p = 0;
9152
9153 if (!decl)
9154 /* An error ocurred, for which grokdeclarator has already issued
9155 an appropriate message. */
9156 return;
9157 else if (! DECL_LANG_SPECIFIC (decl))
9158 {
9159 cp_error ("explicit instantiation of non-template `%#D'", decl);
9160 return;
9161 }
9162 else if (TREE_CODE (decl) == VAR_DECL)
9163 {
9164 /* There is an asymmetry here in the way VAR_DECLs and
9165 FUNCTION_DECLs are handled by grokdeclarator. In the case of
9166 the latter, the DECL we get back will be marked as a
9167 template instantiation, and the appropriate
9168 DECL_TEMPLATE_INFO will be set up. This does not happen for
9169 VAR_DECLs so we do the lookup here. Probably, grokdeclarator
9170 should handle VAR_DECLs as it currently handles
9171 FUNCTION_DECLs. */
9172 result = lookup_field (DECL_CONTEXT (decl), DECL_NAME (decl), 0, 0);
9173 if (result && TREE_CODE (result) != VAR_DECL)
9174 {
9175 cp_error ("no matching template for `%D' found", result);
9176 return;
9177 }
9178 }
9179 else if (TREE_CODE (decl) != FUNCTION_DECL)
9180 {
9181 cp_error ("explicit instantiation of `%#D'", decl);
9182 return;
9183 }
9184 else
9185 result = decl;
9186
9187 /* Check for various error cases. Note that if the explicit
9188 instantiation is legal the RESULT will currently be marked as an
9189 *implicit* instantiation; DECL_EXPLICIT_INSTANTIATION is not set
9190 until we get here. */
9191
9192 if (DECL_TEMPLATE_SPECIALIZATION (result))
9193 {
9194 /* [temp.spec]
9195
9196 No program shall both explicitly instantiate and explicitly
9197 specialize a template. */
9198 cp_pedwarn ("explicit instantiation of `%#D' after", result);
9199 cp_pedwarn_at ("explicit specialization here", result);
9200 return;
9201 }
9202 else if (DECL_EXPLICIT_INSTANTIATION (result))
9203 {
9204 /* [temp.spec]
9205
9206 No program shall explicitly instantiate any template more
9207 than once.
9208
9209 We check DECL_INTERFACE_KNOWN so as not to complain when the first
9210 instantiation was `extern' and the second is not, and EXTERN_P for
9211 the opposite case. If -frepo, chances are we already got marked
9212 as an explicit instantion because of the repo file. */
9213 if (DECL_INTERFACE_KNOWN (result) && !extern_p && !flag_use_repository)
9214 cp_pedwarn ("duplicate explicit instantiation of `%#D'", result);
9215
9216 /* If we've already instantiated the template, just return now. */
9217 if (DECL_INTERFACE_KNOWN (result))
9218 return;
9219 }
9220 else if (!DECL_IMPLICIT_INSTANTIATION (result))
9221 {
9222 cp_error ("no matching template for `%D' found", result);
9223 return;
9224 }
9225 else if (!DECL_TEMPLATE_INFO (result))
9226 {
9227 cp_pedwarn ("explicit instantiation of non-template `%#D'", result);
9228 return;
9229 }
9230
9231 if (flag_external_templates)
9232 return;
9233
9234 if (storage == NULL_TREE)
9235 ;
9236 else if (storage == ridpointers[(int) RID_EXTERN])
9237 {
9238 if (pedantic)
9239 cp_pedwarn ("ISO C++ forbids the use of `extern' on explicit instantiations");
9240 extern_p = 1;
9241 }
9242 else
9243 cp_error ("storage class `%D' applied to template instantiation",
9244 storage);
9245
9246 SET_DECL_EXPLICIT_INSTANTIATION (result);
9247 mark_decl_instantiated (result, extern_p);
9248 repo_template_instantiated (result, extern_p);
9249 if (! extern_p)
9250 instantiate_decl (result, /*defer_ok=*/1);
9251 }
9252
9253 void
9254 mark_class_instantiated (t, extern_p)
9255 tree t;
9256 int extern_p;
9257 {
9258 SET_CLASSTYPE_EXPLICIT_INSTANTIATION (t);
9259 SET_CLASSTYPE_INTERFACE_KNOWN (t);
9260 CLASSTYPE_INTERFACE_ONLY (t) = extern_p;
9261 CLASSTYPE_VTABLE_NEEDS_WRITING (t) = ! extern_p;
9262 TYPE_DECL_SUPPRESS_DEBUG (TYPE_NAME (t)) = extern_p;
9263 if (! extern_p)
9264 {
9265 CLASSTYPE_DEBUG_REQUESTED (t) = 1;
9266 rest_of_type_compilation (t, 1);
9267 }
9268 }
9269
9270 void
9271 do_type_instantiation (t, storage)
9272 tree t, storage;
9273 {
9274 int extern_p = 0;
9275 int nomem_p = 0;
9276 int static_p = 0;
9277
9278 if (TREE_CODE (t) == TYPE_DECL)
9279 t = TREE_TYPE (t);
9280
9281 if (! CLASS_TYPE_P (t) || ! CLASSTYPE_TEMPLATE_INFO (t))
9282 {
9283 cp_error ("explicit instantiation of non-template type `%T'", t);
9284 return;
9285 }
9286
9287 complete_type (t);
9288
9289 /* With -fexternal-templates, explicit instantiations are treated the same
9290 as implicit ones. */
9291 if (flag_external_templates)
9292 return;
9293
9294 if (!COMPLETE_TYPE_P (t))
9295 {
9296 cp_error ("explicit instantiation of `%#T' before definition of template",
9297 t);
9298 return;
9299 }
9300
9301 if (storage != NULL_TREE)
9302 {
9303 if (pedantic)
9304 cp_pedwarn("ISO C++ forbids the use of `%s' on explicit instantiations",
9305 IDENTIFIER_POINTER (storage));
9306
9307 if (storage == ridpointers[(int) RID_INLINE])
9308 nomem_p = 1;
9309 else if (storage == ridpointers[(int) RID_EXTERN])
9310 extern_p = 1;
9311 else if (storage == ridpointers[(int) RID_STATIC])
9312 static_p = 1;
9313 else
9314 {
9315 cp_error ("storage class `%D' applied to template instantiation",
9316 storage);
9317 extern_p = 0;
9318 }
9319 }
9320
9321 if (CLASSTYPE_TEMPLATE_SPECIALIZATION (t))
9322 {
9323 /* [temp.spec]
9324
9325 No program shall both explicitly instantiate and explicitly
9326 specialize a template. */
9327 cp_error ("explicit instantiation of `%#T' after", t);
9328 cp_error_at ("explicit specialization here", t);
9329 return;
9330 }
9331 else if (CLASSTYPE_EXPLICIT_INSTANTIATION (t))
9332 {
9333 /* [temp.spec]
9334
9335 No program shall explicitly instantiate any template more
9336 than once.
9337
9338 If CLASSTYPE_INTERFACE_ONLY, then the first explicit instantiation
9339 was `extern'. If EXTERN_P then the second is. If -frepo, chances
9340 are we already got marked as an explicit instantion because of the
9341 repo file. All these cases are OK. */
9342 if (!CLASSTYPE_INTERFACE_ONLY (t) && !extern_p && !flag_use_repository)
9343 cp_pedwarn ("duplicate explicit instantiation of `%#T'", t);
9344
9345 /* If we've already instantiated the template, just return now. */
9346 if (!CLASSTYPE_INTERFACE_ONLY (t))
9347 return;
9348 }
9349
9350 mark_class_instantiated (t, extern_p);
9351 repo_template_instantiated (t, extern_p);
9352
9353 if (nomem_p)
9354 return;
9355
9356 {
9357 tree tmp;
9358
9359 /* In contrast to implicit instantiation, where only the
9360 declarations, and not the definitions, of members are
9361 instantiated, we have here:
9362
9363 [temp.explicit]
9364
9365 The explicit instantiation of a class template specialization
9366 implies the instantiation of all of its members not
9367 previously explicitly specialized in the translation unit
9368 containing the explicit instantiation.
9369
9370 Of course, we can't instantiate member template classes, since
9371 we don't have any arguments for them. Note that the standard
9372 is unclear on whether the instatiation of the members are
9373 *explicit* instantiations or not. We choose to be generous,
9374 and not set DECL_EXPLICIT_INSTANTIATION. Therefore, we allow
9375 the explicit instantiation of a class where some of the members
9376 have no definition in the current translation unit. */
9377
9378 if (! static_p)
9379 for (tmp = TYPE_METHODS (t); tmp; tmp = TREE_CHAIN (tmp))
9380 if (TREE_CODE (tmp) == FUNCTION_DECL
9381 && DECL_TEMPLATE_INSTANTIATION (tmp))
9382 {
9383 mark_decl_instantiated (tmp, extern_p);
9384 repo_template_instantiated (tmp, extern_p);
9385 if (! extern_p)
9386 instantiate_decl (tmp, /*defer_ok=*/1);
9387 }
9388
9389 for (tmp = TYPE_FIELDS (t); tmp; tmp = TREE_CHAIN (tmp))
9390 if (TREE_CODE (tmp) == VAR_DECL && DECL_TEMPLATE_INSTANTIATION (tmp))
9391 {
9392 mark_decl_instantiated (tmp, extern_p);
9393 repo_template_instantiated (tmp, extern_p);
9394 if (! extern_p)
9395 instantiate_decl (tmp, /*defer_ok=*/1);
9396 }
9397
9398 for (tmp = CLASSTYPE_TAGS (t); tmp; tmp = TREE_CHAIN (tmp))
9399 if (IS_AGGR_TYPE (TREE_VALUE (tmp))
9400 && !uses_template_parms (CLASSTYPE_TI_ARGS (TREE_VALUE (tmp))))
9401 do_type_instantiation (TYPE_MAIN_DECL (TREE_VALUE (tmp)), storage);
9402 }
9403 }
9404
9405 /* Given a function DECL, which is a specialization of TMPL, modify
9406 DECL to be a re-instantiation of TMPL with the same template
9407 arguments. TMPL should be the template into which tsubst'ing
9408 should occur for DECL, not the most general template.
9409
9410 One reason for doing this is a scenario like this:
9411
9412 template <class T>
9413 void f(const T&, int i);
9414
9415 void g() { f(3, 7); }
9416
9417 template <class T>
9418 void f(const T& t, const int i) { }
9419
9420 Note that when the template is first instantiated, with
9421 instantiate_template, the resulting DECL will have no name for the
9422 first parameter, and the wrong type for the second. So, when we go
9423 to instantiate the DECL, we regenerate it. */
9424
9425 static void
9426 regenerate_decl_from_template (decl, tmpl)
9427 tree decl;
9428 tree tmpl;
9429 {
9430 /* The most general version of TMPL. */
9431 tree gen_tmpl;
9432 /* The arguments used to instantiate DECL, from the most general
9433 template. */
9434 tree args;
9435 tree code_pattern;
9436 tree new_decl;
9437 int unregistered;
9438
9439 args = DECL_TI_ARGS (decl);
9440 code_pattern = DECL_TEMPLATE_RESULT (tmpl);
9441
9442 /* Unregister the specialization so that when we tsubst we will not
9443 just return DECL. We don't have to unregister DECL from TMPL
9444 because if would only be registered there if it were a partial
9445 instantiation of a specialization, which it isn't: it's a full
9446 instantiation. */
9447 gen_tmpl = most_general_template (tmpl);
9448 unregistered = unregister_specialization (decl, gen_tmpl);
9449
9450 /* If the DECL was not unregistered then something peculiar is
9451 happening: we created a specialization but did not call
9452 register_specialization for it. */
9453 my_friendly_assert (unregistered, 0);
9454
9455 if (TREE_CODE (decl) == VAR_DECL)
9456 /* Make sure that we can see identifiers, and compute access
9457 correctly, for the class members used in the declaration of
9458 this static variable. */
9459 pushclass (DECL_CONTEXT (decl), 2);
9460
9461 /* Do the substitution to get the new declaration. */
9462 new_decl = tsubst (code_pattern, args, /*complain=*/1, NULL_TREE);
9463
9464 if (TREE_CODE (decl) == VAR_DECL)
9465 {
9466 /* Set up DECL_INITIAL, since tsubst doesn't. */
9467 DECL_INITIAL (new_decl) =
9468 tsubst_expr (DECL_INITIAL (code_pattern), args,
9469 /*complain=*/1, DECL_TI_TEMPLATE (decl));
9470 /* Pop the class context we pushed above. */
9471 popclass ();
9472 }
9473 else if (TREE_CODE (decl) == FUNCTION_DECL)
9474 {
9475 /* Convince duplicate_decls to use the DECL_ARGUMENTS from the
9476 new decl. */
9477 DECL_INITIAL (new_decl) = error_mark_node;
9478 /* And don't complain about a duplicate definition. */
9479 DECL_INITIAL (decl) = NULL_TREE;
9480 }
9481
9482 /* The immediate parent of the new template is still whatever it was
9483 before, even though tsubst sets DECL_TI_TEMPLATE up as the most
9484 general template. We also reset the DECL_ASSEMBLER_NAME since
9485 tsubst always calculates the name as if the function in question
9486 were really a template instance, and sometimes, with friend
9487 functions, this is not so. See tsubst_friend_function for
9488 details. */
9489 DECL_TI_TEMPLATE (new_decl) = DECL_TI_TEMPLATE (decl);
9490 DECL_ASSEMBLER_NAME (new_decl) = DECL_ASSEMBLER_NAME (decl);
9491 DECL_RTL (new_decl) = DECL_RTL (decl);
9492 DECL_USE_TEMPLATE (new_decl) = DECL_USE_TEMPLATE (decl);
9493
9494 /* Call duplicate decls to merge the old and new declarations. */
9495 duplicate_decls (new_decl, decl);
9496
9497 /* Now, re-register the specialization. */
9498 register_specialization (decl, gen_tmpl, args);
9499 }
9500
9501 /* Produce the definition of D, a _DECL generated from a template. If
9502 DEFER_OK is non-zero, then we don't have to actually do the
9503 instantiation now; we just have to do it sometime. */
9504
9505 tree
9506 instantiate_decl (d, defer_ok)
9507 tree d;
9508 int defer_ok;
9509 {
9510 tree tmpl = DECL_TI_TEMPLATE (d);
9511 tree args = DECL_TI_ARGS (d);
9512 tree td;
9513 tree code_pattern;
9514 tree spec;
9515 tree gen_tmpl;
9516 int pattern_defined;
9517 int line = lineno;
9518 const char *file = input_filename;
9519
9520 /* This function should only be used to instantiate templates for
9521 functions and static member variables. */
9522 my_friendly_assert (TREE_CODE (d) == FUNCTION_DECL
9523 || TREE_CODE (d) == VAR_DECL, 0);
9524
9525 /* Don't instantiate cloned functions. Instead, instantiate the
9526 functions they cloned. */
9527 if (TREE_CODE (d) == FUNCTION_DECL && DECL_CLONED_FUNCTION_P (d))
9528 d = DECL_CLONED_FUNCTION (d);
9529
9530 if (DECL_TEMPLATE_INSTANTIATED (d))
9531 /* D has already been instantiated. It might seem reasonable to
9532 check whether or not D is an explict instantiation, and, if so,
9533 stop here. But when an explicit instantiation is deferred
9534 until the end of the compilation, DECL_EXPLICIT_INSTANTIATION
9535 is set, even though we still need to do the instantiation. */
9536 return d;
9537
9538 /* If we already have a specialization of this declaration, then
9539 there's no reason to instantiate it. Note that
9540 retrieve_specialization gives us both instantiations and
9541 specializations, so we must explicitly check
9542 DECL_TEMPLATE_SPECIALIZATION. */
9543 gen_tmpl = most_general_template (tmpl);
9544 spec = retrieve_specialization (gen_tmpl, args);
9545 if (spec != NULL_TREE && DECL_TEMPLATE_SPECIALIZATION (spec))
9546 return spec;
9547
9548 /* This needs to happen before any tsubsting. */
9549 if (! push_tinst_level (d))
9550 return d;
9551
9552 timevar_push (TV_PARSE);
9553
9554 /* Set TD to the template whose DECL_TEMPLATE_RESULT is the pattern
9555 for the instantiation. This is not always the most general
9556 template. Consider, for example:
9557
9558 template <class T>
9559 struct S { template <class U> void f();
9560 template <> void f<int>(); };
9561
9562 and an instantiation of S<double>::f<int>. We want TD to be the
9563 specialization S<T>::f<int>, not the more general S<T>::f<U>. */
9564 td = tmpl;
9565 while (/* An instantiation cannot have a definition, so we need a
9566 more general template. */
9567 DECL_TEMPLATE_INSTANTIATION (td)
9568 /* We must also deal with friend templates. Given:
9569
9570 template <class T> struct S {
9571 template <class U> friend void f() {};
9572 };
9573
9574 S<int>::f<U> say, is not an instantiation of S<T>::f<U>,
9575 so far as the language is concerned, but that's still
9576 where we get the pattern for the instantiation from. On
9577 ther hand, if the definition comes outside the class, say:
9578
9579 template <class T> struct S {
9580 template <class U> friend void f();
9581 };
9582 template <class U> friend void f() {}
9583
9584 we don't need to look any further. That's what the check for
9585 DECL_INITIAL is for. */
9586 || (TREE_CODE (d) == FUNCTION_DECL
9587 && DECL_FRIEND_PSEUDO_TEMPLATE_INSTANTIATION (td)
9588 && !DECL_INITIAL (DECL_TEMPLATE_RESULT (td))))
9589 {
9590 /* The present template, TD, should not be a definition. If it
9591 were a definition, we should be using it! Note that we
9592 cannot restructure the loop to just keep going until we find
9593 a template with a definition, since that might go too far if
9594 a specialization was declared, but not defined. */
9595 my_friendly_assert (!(TREE_CODE (d) == VAR_DECL
9596 && !DECL_IN_AGGR_P (DECL_TEMPLATE_RESULT (td))),
9597 0);
9598
9599 /* Fetch the more general template. */
9600 td = DECL_TI_TEMPLATE (td);
9601 }
9602
9603 code_pattern = DECL_TEMPLATE_RESULT (td);
9604
9605 if (TREE_CODE (d) == FUNCTION_DECL)
9606 pattern_defined = (DECL_SAVED_TREE (code_pattern) != NULL_TREE);
9607 else
9608 pattern_defined = ! DECL_IN_AGGR_P (code_pattern);
9609
9610 push_to_top_level ();
9611 lineno = DECL_SOURCE_LINE (d);
9612 input_filename = DECL_SOURCE_FILE (d);
9613
9614 if (pattern_defined)
9615 {
9616 repo_template_used (d);
9617
9618 if (flag_external_templates && ! DECL_INTERFACE_KNOWN (d))
9619 {
9620 if (flag_alt_external_templates)
9621 {
9622 if (interface_unknown)
9623 warn_if_unknown_interface (d);
9624 }
9625 else if (DECL_INTERFACE_KNOWN (code_pattern))
9626 {
9627 DECL_INTERFACE_KNOWN (d) = 1;
9628 DECL_NOT_REALLY_EXTERN (d) = ! DECL_EXTERNAL (code_pattern);
9629 }
9630 else
9631 warn_if_unknown_interface (code_pattern);
9632 }
9633
9634 if (at_eof)
9635 import_export_decl (d);
9636 }
9637
9638 /* Reject all external templates except inline functions. */
9639 if (DECL_INTERFACE_KNOWN (d)
9640 && ! DECL_NOT_REALLY_EXTERN (d)
9641 && ! (TREE_CODE (d) == FUNCTION_DECL && DECL_INLINE (d)))
9642 goto out;
9643
9644 /* We need to set up DECL_INITIAL regardless of pattern_defined if
9645 the variable is a static const initialized in the class body. */
9646 if (TREE_CODE (d) == VAR_DECL
9647 && TREE_READONLY (d)
9648 && DECL_INITIAL (d) == NULL_TREE
9649 && DECL_INITIAL (code_pattern) != NULL_TREE)
9650 ;
9651 /* Defer all other templates, unless we have been explicitly
9652 forbidden from doing so. We restore the source position here
9653 because it's used by add_pending_template. */
9654 else if (! pattern_defined || defer_ok)
9655 {
9656 lineno = line;
9657 input_filename = file;
9658
9659 if (at_eof && !pattern_defined
9660 && DECL_EXPLICIT_INSTANTIATION (d))
9661 /* [temp.explicit]
9662
9663 The definition of a non-exported function template, a
9664 non-exported member function template, or a non-exported
9665 member function or static data member of a class template
9666 shall be present in every translation unit in which it is
9667 explicitly instantiated. */
9668 cp_error ("explicit instantiation of `%D' but no definition available",
9669 d);
9670
9671 add_pending_template (d);
9672 goto out;
9673 }
9674
9675 /* We're now committed to instantiating this template. Mark it as
9676 instantiated so that recursive calls to instantiate_decl do not
9677 try to instantiate it again. */
9678 DECL_TEMPLATE_INSTANTIATED (d) = 1;
9679
9680 /* Regenerate the declaration in case the template has been modified
9681 by a subsequent redeclaration. */
9682 regenerate_decl_from_template (d, td);
9683
9684 /* We already set the file and line above. Reset them now in case
9685 they changed as a result of calling regenerate_decl_from_template. */
9686 lineno = DECL_SOURCE_LINE (d);
9687 input_filename = DECL_SOURCE_FILE (d);
9688
9689 if (TREE_CODE (d) == VAR_DECL)
9690 {
9691 DECL_IN_AGGR_P (d) = 0;
9692 if (DECL_INTERFACE_KNOWN (d))
9693 DECL_EXTERNAL (d) = ! DECL_NOT_REALLY_EXTERN (d);
9694 else
9695 {
9696 DECL_EXTERNAL (d) = 1;
9697 DECL_NOT_REALLY_EXTERN (d) = 1;
9698 }
9699 cp_finish_decl (d, DECL_INITIAL (d), NULL_TREE, 0);
9700 }
9701 else if (TREE_CODE (d) == FUNCTION_DECL)
9702 {
9703 htab_t saved_local_specializations;
9704
9705 /* Save away the current list, in case we are instantiating one
9706 template from within the body of another. */
9707 saved_local_specializations = local_specializations;
9708
9709 /* Set up the list of local specializations. */
9710 local_specializations = htab_create (37,
9711 htab_hash_pointer,
9712 htab_eq_pointer,
9713 NULL);
9714
9715 /* Set up context. */
9716 start_function (NULL_TREE, d, NULL_TREE, SF_PRE_PARSED);
9717 store_parm_decls ();
9718
9719 /* We already set up __FUNCTION__, etc., so we don't want to do
9720 it again now. */
9721 cp_function_chain->name_declared = 1;
9722
9723 /* Substitute into the body of the function. */
9724 tsubst_expr (DECL_SAVED_TREE (code_pattern), args,
9725 /*complain=*/1, tmpl);
9726
9727 /* We don't need the local specializations any more. */
9728 htab_delete (local_specializations);
9729 local_specializations = saved_local_specializations;
9730
9731 /* Finish the function. */
9732 expand_body (finish_function (0));
9733 }
9734
9735 /* We're not deferring instantiation any more. */
9736 TI_PENDING_TEMPLATE_FLAG (DECL_TEMPLATE_INFO (d)) = 0;
9737
9738 out:
9739 lineno = line;
9740 input_filename = file;
9741
9742 pop_from_top_level ();
9743 pop_tinst_level ();
9744
9745 timevar_pop (TV_PARSE);
9746
9747 return d;
9748 }
9749
9750 /* Run through the list of templates that we wish we could
9751 instantiate, and instantiate any we can. */
9752
9753 int
9754 instantiate_pending_templates ()
9755 {
9756 tree *t;
9757 int instantiated_something = 0;
9758 int reconsider;
9759
9760 do
9761 {
9762 reconsider = 0;
9763
9764 t = &pending_templates;
9765 while (*t)
9766 {
9767 tree instantiation = TREE_VALUE (*t);
9768
9769 reopen_tinst_level (TREE_PURPOSE (*t));
9770
9771 if (TYPE_P (instantiation))
9772 {
9773 tree fn;
9774
9775 if (!COMPLETE_TYPE_P (instantiation))
9776 {
9777 instantiate_class_template (instantiation);
9778 if (CLASSTYPE_TEMPLATE_INSTANTIATION (instantiation))
9779 for (fn = TYPE_METHODS (instantiation);
9780 fn;
9781 fn = TREE_CHAIN (fn))
9782 if (! DECL_ARTIFICIAL (fn))
9783 instantiate_decl (fn, /*defer_ok=*/0);
9784 if (COMPLETE_TYPE_P (instantiation))
9785 {
9786 instantiated_something = 1;
9787 reconsider = 1;
9788 }
9789 }
9790
9791 if (COMPLETE_TYPE_P (instantiation))
9792 /* If INSTANTIATION has been instantiated, then we don't
9793 need to consider it again in the future. */
9794 *t = TREE_CHAIN (*t);
9795 else
9796 t = &TREE_CHAIN (*t);
9797 }
9798 else
9799 {
9800 if (!DECL_TEMPLATE_SPECIALIZATION (instantiation)
9801 && !DECL_TEMPLATE_INSTANTIATED (instantiation))
9802 {
9803 instantiation = instantiate_decl (instantiation,
9804 /*defer_ok=*/0);
9805 if (DECL_TEMPLATE_INSTANTIATED (instantiation))
9806 {
9807 instantiated_something = 1;
9808 reconsider = 1;
9809 }
9810 }
9811
9812 if (DECL_TEMPLATE_SPECIALIZATION (instantiation)
9813 || DECL_TEMPLATE_INSTANTIATED (instantiation))
9814 /* If INSTANTIATION has been instantiated, then we don't
9815 need to consider it again in the future. */
9816 *t = TREE_CHAIN (*t);
9817 else
9818 t = &TREE_CHAIN (*t);
9819 }
9820 tinst_depth = 0;
9821 current_tinst_level = NULL_TREE;
9822 }
9823 template_tail = t;
9824
9825 /* Go through the things that are template instantiations if we are
9826 using guiding declarations. */
9827 t = &maybe_templates;
9828 while (*t)
9829 {
9830 tree template;
9831 tree fn;
9832 tree args;
9833
9834 fn = TREE_VALUE (*t);
9835
9836 if (DECL_INITIAL (fn))
9837 /* If the FN is already defined, then it was either already
9838 instantiated or, even though guiding declarations were
9839 allowed, a non-template definition was provided. */
9840 ;
9841 else
9842 {
9843 template = TREE_PURPOSE (*t);
9844 args = get_bindings (template, fn, NULL_TREE);
9845 fn = instantiate_template (template, args);
9846 instantiate_decl (fn, /*defer_ok=*/0);
9847 reconsider = 1;
9848 }
9849
9850 /* Remove this entry from the chain. */
9851 *t = TREE_CHAIN (*t);
9852 }
9853 maybe_template_tail = t;
9854 }
9855 while (reconsider);
9856
9857 return instantiated_something;
9858 }
9859
9860 /* Substitute ARGVEC into T, which is a list of initializers for
9861 either base class or a non-static data member. The TREE_PURPOSEs
9862 are DECLs, and the TREE_VALUEs are the initializer values. Used by
9863 instantiate_decl. */
9864
9865 static tree
9866 tsubst_initializer_list (t, argvec)
9867 tree t, argvec;
9868 {
9869 tree first = NULL_TREE;
9870 tree *p = &first;
9871
9872 for (; t; t = TREE_CHAIN (t))
9873 {
9874 tree decl;
9875 tree init;
9876 tree val;
9877
9878 decl = tsubst_copy (TREE_PURPOSE (t), argvec, /*complain=*/1,
9879 NULL_TREE);
9880 init = tsubst_expr (TREE_VALUE (t), argvec, /*complain=*/1,
9881 NULL_TREE);
9882
9883 if (!init)
9884 ;
9885 else if (TREE_CODE (init) == TREE_LIST)
9886 for (val = init; val; val = TREE_CHAIN (val))
9887 TREE_VALUE (val) = convert_from_reference (TREE_VALUE (val));
9888 else
9889 init = convert_from_reference (init);
9890
9891 *p = build_tree_list (decl, init);
9892 p = &TREE_CHAIN (*p);
9893 }
9894 return first;
9895 }
9896
9897 /* D is an undefined function declaration in the presence of templates with
9898 the same name, listed in FNS. If one of them can produce D as an
9899 instantiation, remember this so we can instantiate it at EOF if D has
9900 not been defined by that time. */
9901
9902 void
9903 add_maybe_template (d, fns)
9904 tree d, fns;
9905 {
9906 tree t;
9907
9908 if (DECL_MAYBE_TEMPLATE (d))
9909 return;
9910
9911 t = most_specialized (fns, d, NULL_TREE);
9912 if (! t)
9913 return;
9914 if (t == error_mark_node)
9915 {
9916 cp_error ("ambiguous template instantiation for `%D'", d);
9917 return;
9918 }
9919
9920 *maybe_template_tail = tree_cons (t, d, NULL_TREE);
9921 maybe_template_tail = &TREE_CHAIN (*maybe_template_tail);
9922 DECL_MAYBE_TEMPLATE (d) = 1;
9923 }
9924
9925 /* Set CURRENT_ACCESS_SPECIFIER based on the protection of DECL. */
9926
9927 static void
9928 set_current_access_from_decl (decl)
9929 tree decl;
9930 {
9931 if (TREE_PRIVATE (decl))
9932 current_access_specifier = access_private_node;
9933 else if (TREE_PROTECTED (decl))
9934 current_access_specifier = access_protected_node;
9935 else
9936 current_access_specifier = access_public_node;
9937 }
9938
9939 /* Instantiate an enumerated type. TAG is the template type, NEWTAG
9940 is the instantiation (which should have been created with
9941 start_enum) and ARGS are the template arguments to use. */
9942
9943 static void
9944 tsubst_enum (tag, newtag, args)
9945 tree tag;
9946 tree newtag;
9947 tree args;
9948 {
9949 tree e;
9950
9951 for (e = TYPE_VALUES (tag); e; e = TREE_CHAIN (e))
9952 {
9953 tree value;
9954
9955 /* Note that in a template enum, the TREE_VALUE is the
9956 CONST_DECL, not the corresponding INTEGER_CST. */
9957 value = tsubst_expr (DECL_INITIAL (TREE_VALUE (e)),
9958 args, /*complain=*/1,
9959 NULL_TREE);
9960
9961 /* Give this enumeration constant the correct access. */
9962 set_current_access_from_decl (TREE_VALUE (e));
9963
9964 /* Actually build the enumerator itself. */
9965 build_enumerator (TREE_PURPOSE (e), value, newtag);
9966 }
9967
9968 finish_enum (newtag);
9969 }
9970
9971 /* DECL is a FUNCTION_DECL that is a template specialization. Return
9972 its type -- but without substituting the innermost set of template
9973 arguments. So, innermost set of template parameters will appear in
9974 the type. If CONTEXTP is non-NULL, then the partially substituted
9975 DECL_CONTEXT (if any) will also be filled in. Similarly, TPARMSP
9976 will be filled in with the substituted template parameters, if it
9977 is non-NULL. */
9978
9979 tree
9980 get_mostly_instantiated_function_type (decl, contextp, tparmsp)
9981 tree decl;
9982 tree *contextp;
9983 tree *tparmsp;
9984 {
9985 tree context = NULL_TREE;
9986 tree fn_type;
9987 tree tmpl;
9988 tree targs;
9989 tree tparms;
9990 int parm_depth;
9991
9992 tmpl = most_general_template (DECL_TI_TEMPLATE (decl));
9993 targs = DECL_TI_ARGS (decl);
9994 tparms = DECL_TEMPLATE_PARMS (tmpl);
9995 parm_depth = TMPL_PARMS_DEPTH (tparms);
9996
9997 /* There should be as many levels of arguments as there are levels
9998 of parameters. */
9999 my_friendly_assert (parm_depth == TMPL_ARGS_DEPTH (targs), 0);
10000
10001 fn_type = TREE_TYPE (tmpl);
10002 if (DECL_STATIC_FUNCTION_P (decl))
10003 context = DECL_CONTEXT (decl);
10004
10005 if (parm_depth == 1)
10006 /* No substitution is necessary. */
10007 ;
10008 else
10009 {
10010 int i;
10011 tree partial_args;
10012
10013 /* Replace the innermost level of the TARGS with NULL_TREEs to
10014 let tsubst know not to subsitute for those parameters. */
10015 partial_args = make_tree_vec (TREE_VEC_LENGTH (targs));
10016 for (i = 1; i < TMPL_ARGS_DEPTH (targs); ++i)
10017 SET_TMPL_ARGS_LEVEL (partial_args, i,
10018 TMPL_ARGS_LEVEL (targs, i));
10019 SET_TMPL_ARGS_LEVEL (partial_args,
10020 TMPL_ARGS_DEPTH (targs),
10021 make_tree_vec (DECL_NTPARMS (tmpl)));
10022
10023 /* Now, do the (partial) substitution to figure out the
10024 appropriate function type. */
10025 fn_type = tsubst (fn_type, partial_args, /*complain=*/1, NULL_TREE);
10026 if (DECL_STATIC_FUNCTION_P (decl))
10027 context = tsubst (context, partial_args, /*complain=*/1, NULL_TREE);
10028
10029 /* Substitute into the template parameters to obtain the real
10030 innermost set of parameters. This step is important if the
10031 innermost set of template parameters contains value
10032 parameters whose types depend on outer template parameters. */
10033 TREE_VEC_LENGTH (partial_args)--;
10034 tparms = tsubst_template_parms (tparms, partial_args, /*complain=*/1);
10035 }
10036
10037 if (contextp)
10038 *contextp = context;
10039 if (tparmsp)
10040 *tparmsp = tparms;
10041
10042 return fn_type;
10043 }
10044
10045 /* Set the DECL_ASSEMBLER_NAME for DECL, which is a FUNCTION_DECL that
10046 is either an instantiation or specialization of a template
10047 function. */
10048
10049 static void
10050 set_mangled_name_for_template_decl (decl)
10051 tree decl;
10052 {
10053 tree context = NULL_TREE;
10054 tree fn_type;
10055 tree ret_type;
10056 tree parm_types;
10057 tree tparms;
10058 tree targs;
10059
10060 my_friendly_assert (TREE_CODE (decl) == FUNCTION_DECL, 0);
10061 my_friendly_assert (DECL_TEMPLATE_INFO (decl) != NULL_TREE, 0);
10062
10063 /* Under the new ABI, we don't need special machinery. */
10064 if (flag_new_abi)
10065 {
10066 set_mangled_name_for_decl (decl);
10067 return;
10068 }
10069
10070 /* The names of template functions must be mangled so as to indicate
10071 what template is being specialized with what template arguments.
10072 For example, each of the following three functions must get
10073 different mangled names:
10074
10075 void f(int);
10076 template <> void f<7>(int);
10077 template <> void f<8>(int); */
10078
10079 targs = DECL_TI_ARGS (decl);
10080 if (uses_template_parms (targs))
10081 /* This DECL is for a partial instantiation. There's no need to
10082 mangle the name of such an entity. */
10083 return;
10084
10085 /* We now compute the PARMS and RET_TYPE to give to
10086 build_decl_overload_real. The PARMS and RET_TYPE are the
10087 parameter and return types of the template, after all but the
10088 innermost template arguments have been substituted, not the
10089 parameter and return types of the function DECL. For example,
10090 given:
10091
10092 template <class T> T f(T);
10093
10094 both PARMS and RET_TYPE should be `T' even if DECL is `int f(int)'.
10095 A more subtle example is:
10096
10097 template <class T> struct S { template <class U> void f(T, U); }
10098
10099 Here, if DECL is `void S<int>::f(int, double)', PARMS should be
10100 {int, U}. Thus, the args that we want to subsitute into the
10101 return and parameter type for the function are those in TARGS,
10102 with the innermost level omitted. */
10103 fn_type = get_mostly_instantiated_function_type (decl, &context, &tparms);
10104
10105 /* Now, get the innermost parameters and arguments, and figure out
10106 the parameter and return types. */
10107 tparms = INNERMOST_TEMPLATE_PARMS (tparms);
10108 targs = INNERMOST_TEMPLATE_ARGS (targs);
10109 ret_type = TREE_TYPE (fn_type);
10110 parm_types = TYPE_ARG_TYPES (fn_type);
10111
10112 /* For a static member function, we generate a fake `this' pointer,
10113 for the purposes of mangling. This indicates of which class the
10114 function is a member. Because of:
10115
10116 [class.static]
10117
10118 There shall not be a static and a nonstatic member function
10119 with the same name and the same parameter types
10120
10121 we don't have to worry that this will result in a clash with a
10122 non-static member function. */
10123 if (DECL_STATIC_FUNCTION_P (decl))
10124 parm_types = hash_tree_chain (build_pointer_type (context), parm_types);
10125
10126 /* There should be the same number of template parameters as
10127 template arguments. */
10128 my_friendly_assert (TREE_VEC_LENGTH (tparms) == TREE_VEC_LENGTH (targs),
10129 0);
10130
10131 /* Actually set the DECL_ASSEMBLER_NAME. */
10132 DECL_ASSEMBLER_NAME (decl)
10133 = build_decl_overload_real (decl, parm_types, ret_type,
10134 tparms, targs,
10135 DECL_FUNCTION_MEMBER_P (decl)
10136 + DECL_MAYBE_IN_CHARGE_CONSTRUCTOR_P (decl));
10137 }