1 /* Handle parameterized types (templates) for GNU C++.
2 Copyright (C) 1992, 93-97, 1998, 1999, 2000 Free Software Foundation, Inc.
3 Written by Ken Raeburn (raeburn@cygnus.com) while at Watchmaker Computing.
4 Rewritten by Jason Merrill (jason@cygnus.com).
6 This file is part of GNU CC.
8 GNU CC is free software; you can redistribute it and/or modify
9 it under the terms of the GNU General Public License as published by
10 the Free Software Foundation; either version 2, or (at your option)
13 GNU CC is distributed in the hope that it will be useful,
14 but WITHOUT ANY WARRANTY; without even the implied warranty of
15 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
16 GNU General Public License for more details.
18 You should have received a copy of the GNU General Public License
19 along with GNU CC; see the file COPYING. If not, write to
20 the Free Software Foundation, 59 Temple Place - Suite 330,
21 Boston, MA 02111-1307, USA. */
23 /* Known bugs or deficiencies include:
25 all methods must be provided in header files; can't use a source
26 file that contains only the method templates and "just win". */
46 /* The type of functions taking a tree, and some additional data, and
48 typedef int (*tree_fn_t) PARAMS ((tree, void*));
50 extern struct obstack permanent_obstack;
53 extern char *input_filename;
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;
65 static tree maybe_templates;
66 static tree *maybe_template_tail = &maybe_templates;
68 int processing_template_parmlist;
69 static int template_header_count;
71 static tree saved_trees;
72 static varray_type inline_parm_levels;
73 static size_t inline_parm_levels_used;
75 #define obstack_chunk_alloc xmalloc
76 #define obstack_chunk_free free
78 #define UNIFY_ALLOW_NONE 0
79 #define UNIFY_ALLOW_MORE_CV_QUAL 1
80 #define UNIFY_ALLOW_LESS_CV_QUAL 2
81 #define UNIFY_ALLOW_DERIVED 4
82 #define UNIFY_ALLOW_INTEGER 8
84 #define GTB_VIA_VIRTUAL 1 /* The base class we are examining is
85 virtual, or a base class of a virtual
87 #define GTB_IGNORE_TYPE 2 /* We don't need to try to unify the current
88 type with the desired type. */
90 static int resolve_overloaded_unification PARAMS ((tree, tree, tree, tree,
91 unification_kind_t, int));
92 static int try_one_overload PARAMS ((tree, tree, tree, tree, tree,
93 unification_kind_t, int));
94 static int unify PARAMS ((tree, tree, tree, tree, int));
95 static void add_pending_template PARAMS ((tree));
96 static int push_tinst_level PARAMS ((tree));
97 static tree classtype_mangled_name PARAMS ((tree));
98 static char *mangle_class_name_for_template PARAMS ((char *, tree, tree));
99 static tree tsubst_expr_values PARAMS ((tree, tree));
100 static int list_eq PARAMS ((tree, tree));
101 static tree get_class_bindings PARAMS ((tree, tree, tree));
102 static tree coerce_template_parms PARAMS ((tree, tree, tree, int, int));
103 static void tsubst_enum PARAMS ((tree, tree, tree));
104 static tree add_to_template_args PARAMS ((tree, tree));
105 static tree add_outermost_template_args PARAMS ((tree, tree));
106 static void maybe_adjust_types_for_deduction PARAMS ((unification_kind_t, tree*,
108 static int type_unification_real PARAMS ((tree, tree, tree, tree,
109 int, unification_kind_t, int));
110 static void note_template_header PARAMS ((int));
111 static tree maybe_fold_nontype_arg PARAMS ((tree));
112 static tree convert_nontype_argument PARAMS ((tree, tree));
113 static tree convert_template_argument PARAMS ((tree, tree, tree, int,
115 static tree get_bindings_overload PARAMS ((tree, tree, tree));
116 static int for_each_template_parm PARAMS ((tree, tree_fn_t, void*));
117 static tree build_template_parm_index PARAMS ((int, int, int, tree, tree));
118 static int inline_needs_template_parms PARAMS ((tree));
119 static void push_inline_template_parms_recursive PARAMS ((tree, int));
120 static tree retrieve_specialization PARAMS ((tree, tree));
121 static tree retrieve_local_specialization PARAMS ((tree, tree));
122 static tree register_specialization PARAMS ((tree, tree, tree));
123 static tree register_local_specialization PARAMS ((tree, tree, tree));
124 static int unregister_specialization PARAMS ((tree, tree));
125 static tree reduce_template_parm_level PARAMS ((tree, tree, int));
126 static tree build_template_decl PARAMS ((tree, tree));
127 static int mark_template_parm PARAMS ((tree, void *));
128 static tree tsubst_friend_function PARAMS ((tree, tree));
129 static tree tsubst_friend_class PARAMS ((tree, tree));
130 static tree get_bindings_real PARAMS ((tree, tree, tree, int));
131 static int template_decl_level PARAMS ((tree));
132 static tree maybe_get_template_decl_from_type_decl PARAMS ((tree));
133 static int check_cv_quals_for_unify PARAMS ((int, tree, tree));
134 static tree tsubst_template_arg_vector PARAMS ((tree, tree, int));
135 static tree tsubst_template_parms PARAMS ((tree, tree, int));
136 static void regenerate_decl_from_template PARAMS ((tree, tree));
137 static tree most_specialized PARAMS ((tree, tree, tree));
138 static tree most_specialized_class PARAMS ((tree, tree));
139 static void set_mangled_name_for_template_decl PARAMS ((tree));
140 static int template_class_depth_real PARAMS ((tree, int));
141 static tree tsubst_aggr_type PARAMS ((tree, tree, int, tree, int));
142 static tree tsubst_decl PARAMS ((tree, tree, tree, tree));
143 static tree tsubst_arg_types PARAMS ((tree, tree, int, tree));
144 static tree tsubst_function_type PARAMS ((tree, tree, int, tree));
145 static void check_specialization_scope PARAMS ((void));
146 static tree process_partial_specialization PARAMS ((tree));
147 static void set_current_access_from_decl PARAMS ((tree));
148 static void check_default_tmpl_args PARAMS ((tree, tree, int, int));
149 static tree tsubst_call_declarator_parms PARAMS ((tree, tree, int, tree));
150 static tree get_template_base_recursive PARAMS ((tree, tree,
151 tree, tree, tree, int));
152 static tree get_template_base PARAMS ((tree, tree, tree, tree));
153 static tree try_class_unification PARAMS ((tree, tree, tree, tree));
154 static int coerce_template_template_parms PARAMS ((tree, tree, int,
156 static tree determine_specialization PARAMS ((tree, tree, tree *, int));
157 static int template_args_equal PARAMS ((tree, tree));
158 static void print_template_context PARAMS ((int));
159 static void tsubst_default_arguments PARAMS ((tree));
160 static tree for_each_template_parm_r PARAMS ((tree *, int *, void *));
162 /* Called once to initialize pt.c. */
167 ggc_add_tree_root (&pending_templates, 1);
168 ggc_add_tree_root (&maybe_templates, 1);
169 ggc_add_tree_root (&saved_trees, 1);
172 /* Do any processing required when DECL (a member template declaration
173 using TEMPLATE_PARAMETERS as its innermost parameter list) is
174 finished. Returns the TEMPLATE_DECL corresponding to DECL, unless
175 it is a specialization, in which case the DECL itself is returned. */
178 finish_member_template_decl (decl)
181 if (decl == NULL_TREE || decl == void_type_node)
183 else if (decl == error_mark_node)
184 /* By returning NULL_TREE, the parser will just ignore this
185 declaration. We have already issued the error. */
187 else if (TREE_CODE (decl) == TREE_LIST)
189 /* Assume that the class is the only declspec. */
190 decl = TREE_VALUE (decl);
191 if (IS_AGGR_TYPE (decl) && CLASSTYPE_TEMPLATE_INFO (decl)
192 && ! CLASSTYPE_TEMPLATE_SPECIALIZATION (decl))
194 tree tmpl = CLASSTYPE_TI_TEMPLATE (decl);
195 check_member_template (tmpl);
200 else if (TREE_CODE (decl) == FIELD_DECL)
201 cp_error ("data member `%D' cannot be a member template", decl);
202 else if (DECL_TEMPLATE_INFO (decl))
204 if (!DECL_TEMPLATE_SPECIALIZATION (decl))
206 check_member_template (DECL_TI_TEMPLATE (decl));
207 return DECL_TI_TEMPLATE (decl);
213 cp_error ("invalid member template declaration `%D'", decl);
215 return error_mark_node;
218 /* Returns the template nesting level of the indicated class TYPE.
228 A<T>::B<U> has depth two, while A<T> has depth one.
229 Both A<T>::B<int> and A<int>::B<U> have depth one, if
230 COUNT_SPECIALIZATIONS is 0 or if they are instantiations, not
233 This function is guaranteed to return 0 if passed NULL_TREE so
234 that, for example, `template_class_depth (current_class_type)' is
238 template_class_depth_real (type, count_specializations)
240 int count_specializations;
245 type && TREE_CODE (type) != NAMESPACE_DECL;
246 type = (TREE_CODE (type) == FUNCTION_DECL)
247 ? CP_DECL_CONTEXT (type) : TYPE_CONTEXT (type))
249 if (TREE_CODE (type) != FUNCTION_DECL)
251 if (CLASSTYPE_TEMPLATE_INFO (type)
252 && PRIMARY_TEMPLATE_P (CLASSTYPE_TI_TEMPLATE (type))
253 && ((count_specializations
254 && CLASSTYPE_TEMPLATE_SPECIALIZATION (type))
255 || uses_template_parms (CLASSTYPE_TI_ARGS (type))))
260 if (DECL_TEMPLATE_INFO (type)
261 && PRIMARY_TEMPLATE_P (DECL_TI_TEMPLATE (type))
262 && ((count_specializations
263 && DECL_TEMPLATE_SPECIALIZATION (type))
264 || uses_template_parms (DECL_TI_ARGS (type))))
272 /* Returns the template nesting level of the indicated class TYPE.
273 Like template_class_depth_real, but instantiations do not count in
277 template_class_depth (type)
280 return template_class_depth_real (type, /*count_specializations=*/0);
283 /* Returns 1 if processing DECL as part of do_pending_inlines
284 needs us to push template parms. */
287 inline_needs_template_parms (decl)
290 if (! DECL_TEMPLATE_INFO (decl))
293 return (TMPL_PARMS_DEPTH (DECL_TEMPLATE_PARMS (most_general_template (decl)))
294 > (processing_template_decl + DECL_TEMPLATE_SPECIALIZATION (decl)));
297 /* Subroutine of maybe_begin_member_template_processing.
298 Push the template parms in PARMS, starting from LEVELS steps into the
299 chain, and ending at the beginning, since template parms are listed
303 push_inline_template_parms_recursive (parmlist, levels)
307 tree parms = TREE_VALUE (parmlist);
311 push_inline_template_parms_recursive (TREE_CHAIN (parmlist), levels - 1);
313 ++processing_template_decl;
314 current_template_parms
315 = tree_cons (build_int_2 (0, processing_template_decl),
316 parms, current_template_parms);
317 TEMPLATE_PARMS_FOR_INLINE (current_template_parms) = 1;
320 for (i = 0; i < TREE_VEC_LENGTH (parms); ++i)
322 tree parm = TREE_VALUE (TREE_VEC_ELT (parms, i));
323 my_friendly_assert (TREE_CODE_CLASS (TREE_CODE (parm)) == 'd', 0);
325 switch (TREE_CODE (parm))
334 /* Make a CONST_DECL as is done in process_template_parm.
335 It is ugly that we recreate this here; the original
336 version built in process_template_parm is no longer
338 tree decl = build_decl (CONST_DECL, DECL_NAME (parm),
340 SET_DECL_ARTIFICIAL (decl);
341 DECL_INITIAL (decl) = DECL_INITIAL (parm);
342 SET_DECL_TEMPLATE_PARM_P (decl);
348 my_friendly_abort (0);
353 /* Restore the template parameter context for a member template or
354 a friend template defined in a class definition. */
357 maybe_begin_member_template_processing (decl)
363 if (inline_needs_template_parms (decl))
365 parms = DECL_TEMPLATE_PARMS (most_general_template (decl));
366 levels = TMPL_PARMS_DEPTH (parms) - processing_template_decl;
368 if (DECL_TEMPLATE_SPECIALIZATION (decl))
371 parms = TREE_CHAIN (parms);
374 push_inline_template_parms_recursive (parms, levels);
377 /* Remember how many levels of template parameters we pushed so that
378 we can pop them later. */
379 if (!inline_parm_levels)
380 VARRAY_INT_INIT (inline_parm_levels, 4, "inline_parm_levels");
381 if (inline_parm_levels_used == inline_parm_levels->num_elements)
382 VARRAY_GROW (inline_parm_levels, 2 * inline_parm_levels_used);
383 VARRAY_INT (inline_parm_levels, inline_parm_levels_used) = levels;
384 ++inline_parm_levels_used;
387 /* Undo the effects of begin_member_template_processing. */
390 maybe_end_member_template_processing ()
394 if (!inline_parm_levels_used)
397 --inline_parm_levels_used;
399 i < VARRAY_INT (inline_parm_levels, inline_parm_levels_used);
402 --processing_template_decl;
403 current_template_parms = TREE_CHAIN (current_template_parms);
408 /* Returns non-zero iff T is a member template function. We must be
411 template <class T> class C { void f(); }
413 Here, f is a template function, and a member, but not a member
414 template. This function does not concern itself with the origin of
415 T, only its present state. So if we have
417 template <class T> class C { template <class U> void f(U); }
419 then neither C<int>::f<char> nor C<T>::f<double> is considered
420 to be a member template. But, `template <class U> void
421 C<int>::f(U)' is considered a member template. */
424 is_member_template (t)
427 if (!DECL_FUNCTION_TEMPLATE_P (t))
428 /* Anything that isn't a function or a template function is
429 certainly not a member template. */
432 /* A local class can't have member templates. */
433 if (decl_function_context (t))
436 return (DECL_FUNCTION_MEMBER_P (DECL_TEMPLATE_RESULT (t))
437 /* If there are more levels of template parameters than
438 there are template classes surrounding the declaration,
439 then we have a member template. */
440 && (TMPL_PARMS_DEPTH (DECL_TEMPLATE_PARMS (t)) >
441 template_class_depth (DECL_CONTEXT (t))));
445 /* Returns non-zero iff T is a member template class. See
446 is_member_template for a description of what precisely constitutes
447 a member template. */
450 is_member_template_class (t)
453 if (!DECL_CLASS_TEMPLATE_P (t))
454 /* Anything that isn't a class template, is certainly not a member
458 if (!DECL_CLASS_SCOPE_P (t))
459 /* Anything whose context isn't a class type is surely not a
463 /* If there are more levels of template parameters than there are
464 template classes surrounding the declaration, then we have a
466 return (TMPL_PARMS_DEPTH (DECL_TEMPLATE_PARMS (t)) >
467 template_class_depth (DECL_CONTEXT (t)));
471 /* Return a new template argument vector which contains all of ARGS,
472 but has as its innermost set of arguments the EXTRA_ARGS. The
473 resulting vector will be built on a temporary obstack, and so must
474 be explicitly copied to the permanent obstack, if required. */
477 add_to_template_args (args, extra_args)
486 extra_depth = TMPL_ARGS_DEPTH (extra_args);
487 new_args = make_tree_vec (TMPL_ARGS_DEPTH (args) + extra_depth);
489 for (i = 1; i <= TMPL_ARGS_DEPTH (args); ++i)
490 SET_TMPL_ARGS_LEVEL (new_args, i, TMPL_ARGS_LEVEL (args, i));
492 for (j = 1; j <= extra_depth; ++j, ++i)
493 SET_TMPL_ARGS_LEVEL (new_args, i, TMPL_ARGS_LEVEL (extra_args, j));
498 /* Like add_to_template_args, but only the outermost ARGS are added to
499 the EXTRA_ARGS. In particular, all but TMPL_ARGS_DEPTH
500 (EXTRA_ARGS) levels are added. This function is used to combine
501 the template arguments from a partial instantiation with the
502 template arguments used to attain the full instantiation from the
503 partial instantiation. */
506 add_outermost_template_args (args, extra_args)
512 /* If there are more levels of EXTRA_ARGS than there are ARGS,
513 something very fishy is going on. */
514 my_friendly_assert (TMPL_ARGS_DEPTH (args) >= TMPL_ARGS_DEPTH (extra_args),
517 /* If *all* the new arguments will be the EXTRA_ARGS, just return
519 if (TMPL_ARGS_DEPTH (args) == TMPL_ARGS_DEPTH (extra_args))
522 /* For the moment, we make ARGS look like it contains fewer levels. */
523 TREE_VEC_LENGTH (args) -= TMPL_ARGS_DEPTH (extra_args);
525 new_args = add_to_template_args (args, extra_args);
527 /* Now, we restore ARGS to its full dimensions. */
528 TREE_VEC_LENGTH (args) += TMPL_ARGS_DEPTH (extra_args);
533 /* We've got a template header coming up; push to a new level for storing
537 begin_template_parm_list ()
539 /* We use a non-tag-transparent scope here, which causes pushtag to
540 put tags in this scope, rather than in the enclosing class or
541 namespace scope. This is the right thing, since we want
542 TEMPLATE_DECLS, and not TYPE_DECLS for template classes. For a
543 global template class, push_template_decl handles putting the
544 TEMPLATE_DECL into top-level scope. For a nested template class,
547 template <class T> struct S1 {
548 template <class T> struct S2 {};
551 pushtag contains special code to call pushdecl_with_scope on the
552 TEMPLATE_DECL for S2. */
554 declare_pseudo_global_level ();
555 ++processing_template_decl;
556 ++processing_template_parmlist;
557 note_template_header (0);
560 /* This routine is called when a specialization is declared. If it is
561 illegal to declare a specialization here, an error is reported. */
564 check_specialization_scope ()
566 tree scope = current_scope ();
570 An explicit specialization shall be declared in the namespace of
571 which the template is a member, or, for member templates, in the
572 namespace of which the enclosing class or enclosing class
573 template is a member. An explicit specialization of a member
574 function, member class or static data member of a class template
575 shall be declared in the namespace of which the class template
577 if (scope && TREE_CODE (scope) != NAMESPACE_DECL)
578 cp_error ("explicit specialization in non-namespace scope `%D'",
583 In an explicit specialization declaration for a member of a class
584 template or a member template that appears in namespace scope,
585 the member template and some of its enclosing class templates may
586 remain unspecialized, except that the declaration shall not
587 explicitly specialize a class member template if its enclosing
588 class templates are not explicitly specialized as well. */
589 if (current_template_parms)
590 cp_error ("enclosing class templates are not explicitly specialized");
593 /* We've just seen template <>. */
596 begin_specialization ()
598 note_template_header (1);
599 check_specialization_scope ();
602 /* Called at then end of processing a declaration preceeded by
606 end_specialization ()
608 reset_specialization ();
611 /* Any template <>'s that we have seen thus far are not referring to a
612 function specialization. */
615 reset_specialization ()
617 processing_specialization = 0;
618 template_header_count = 0;
621 /* We've just seen a template header. If SPECIALIZATION is non-zero,
622 it was of the form template <>. */
625 note_template_header (specialization)
628 processing_specialization = specialization;
629 template_header_count++;
632 /* We're beginning an explicit instantiation. */
635 begin_explicit_instantiation ()
637 ++processing_explicit_instantiation;
642 end_explicit_instantiation ()
644 my_friendly_assert(processing_explicit_instantiation > 0, 0);
645 --processing_explicit_instantiation;
648 /* The TYPE is being declared. If it is a template type, that means it
649 is a partial specialization. Do appropriate error-checking. */
652 maybe_process_partial_specialization (type)
655 if (IS_AGGR_TYPE (type) && CLASSTYPE_USE_TEMPLATE (type))
657 if (CLASSTYPE_IMPLICIT_INSTANTIATION (type)
658 && TYPE_SIZE (type) == NULL_TREE)
660 if (current_namespace
661 != decl_namespace_context (CLASSTYPE_TI_TEMPLATE (type)))
663 cp_pedwarn ("specializing `%#T' in different namespace", type);
664 cp_pedwarn_at (" from definition of `%#D'",
665 CLASSTYPE_TI_TEMPLATE (type));
667 SET_CLASSTYPE_TEMPLATE_SPECIALIZATION (type);
668 if (processing_template_decl)
669 push_template_decl (TYPE_MAIN_DECL (type));
671 else if (CLASSTYPE_TEMPLATE_INSTANTIATION (type))
672 cp_error ("specialization of `%T' after instantiation", type);
674 else if (processing_specialization)
675 cp_error ("explicit specialization of non-template `%T'", type);
678 /* Retrieve the specialization (in the sense of [temp.spec] - a
679 specialization is either an instantiation or an explicit
680 specialization) of TMPL for the given template ARGS. If there is
681 no such specialization, return NULL_TREE. The ARGS are a vector of
682 arguments, or a vector of vectors of arguments, in the case of
683 templates with more than one level of parameters. */
686 retrieve_specialization (tmpl, args)
692 my_friendly_assert (TREE_CODE (tmpl) == TEMPLATE_DECL, 0);
694 /* There should be as many levels of arguments as there are
695 levels of parameters. */
696 my_friendly_assert (TMPL_ARGS_DEPTH (args)
697 == TMPL_PARMS_DEPTH (DECL_TEMPLATE_PARMS (tmpl)),
700 for (s = DECL_TEMPLATE_SPECIALIZATIONS (tmpl);
703 if (comp_template_args (TREE_PURPOSE (s), args))
704 return TREE_VALUE (s);
709 /* Like retrieve_speciailization, but for local declarations. FN is
710 the function in which we are looking for an instantiation. */
713 retrieve_local_specialization (tmpl, fn)
717 tree s = purpose_member (fn, DECL_TEMPLATE_SPECIALIZATIONS (tmpl));
718 return s ? TREE_VALUE (s) : NULL_TREE;
721 /* Returns non-zero iff DECL is a specialization of TMPL. */
724 is_specialization_of (decl, tmpl)
730 if (TREE_CODE (decl) == FUNCTION_DECL)
734 t = DECL_TEMPLATE_INFO (t) ? DECL_TI_TEMPLATE (t) : NULL_TREE)
740 my_friendly_assert (TREE_CODE (decl) == TYPE_DECL, 0);
742 for (t = TREE_TYPE (decl);
744 t = CLASSTYPE_USE_TEMPLATE (t)
745 ? TREE_TYPE (CLASSTYPE_TI_TEMPLATE (t)) : NULL_TREE)
746 if (same_type_p (TYPE_MAIN_VARIANT (t),
747 TYPE_MAIN_VARIANT (TREE_TYPE (tmpl))))
754 /* Register the specialization SPEC as a specialization of TMPL with
755 the indicated ARGS. Returns SPEC, or an equivalent prior
756 declaration, if available. */
759 register_specialization (spec, tmpl, args)
766 my_friendly_assert (TREE_CODE (tmpl) == TEMPLATE_DECL, 0);
768 if (TREE_CODE (spec) == FUNCTION_DECL
769 && uses_template_parms (DECL_TI_ARGS (spec)))
770 /* This is the FUNCTION_DECL for a partial instantiation. Don't
771 register it; we want the corresponding TEMPLATE_DECL instead.
772 We use `uses_template_parms (DECL_TI_ARGS (spec))' rather than
773 the more obvious `uses_template_parms (spec)' to avoid problems
774 with default function arguments. In particular, given
777 template <class T> void f(T t1, T t = T())
779 the default argument expression is not substituted for in an
780 instantiation unless and until it is actually needed. */
783 /* There should be as many levels of arguments as there are
784 levels of parameters. */
785 my_friendly_assert (TMPL_ARGS_DEPTH (args)
786 == TMPL_PARMS_DEPTH (DECL_TEMPLATE_PARMS (tmpl)),
789 for (s = DECL_TEMPLATE_SPECIALIZATIONS (tmpl);
793 tree fn = TREE_VALUE (s);
795 /* We can sometimes try to re-register a specialization that we've
796 already got. In particular, regenerate_decl_from_template
797 calls duplicate_decls which will update the specialization
798 list. But, we'll still get called again here anyhow. It's
799 more convenient to simply allow this than to try to prevent it. */
802 else if (comp_template_args (TREE_PURPOSE (s), args))
804 if (DECL_TEMPLATE_SPECIALIZATION (spec))
806 if (DECL_TEMPLATE_INSTANTIATION (fn))
809 || DECL_EXPLICIT_INSTANTIATION (fn))
811 cp_error ("specialization of %D after instantiation",
817 /* This situation should occur only if the first
818 specialization is an implicit instantiation,
819 the second is an explicit specialization, and
820 the implicit instantiation has not yet been
821 used. That situation can occur if we have
822 implicitly instantiated a member function and
823 then specialized it later.
825 We can also wind up here if a friend
826 declaration that looked like an instantiation
827 turns out to be a specialization:
829 template <class T> void foo(T);
830 class S { friend void foo<>(int) };
831 template <> void foo(int);
833 We transform the existing DECL in place so that
834 any pointers to it become pointers to the
837 If there was a definition for the template, but
838 not for the specialization, we want this to
839 look as if there is no definition, and vice
841 DECL_INITIAL (fn) = NULL_TREE;
842 duplicate_decls (spec, fn);
847 else if (DECL_TEMPLATE_SPECIALIZATION (fn))
849 duplicate_decls (spec, fn);
856 DECL_TEMPLATE_SPECIALIZATIONS (tmpl)
857 = tree_cons (args, spec, DECL_TEMPLATE_SPECIALIZATIONS (tmpl));
862 /* Unregister the specialization SPEC as a specialization of TMPL.
863 Returns nonzero if the SPEC was listed as a specialization of
867 unregister_specialization (spec, tmpl)
873 for (s = &DECL_TEMPLATE_SPECIALIZATIONS (tmpl);
875 s = &TREE_CHAIN (*s))
876 if (TREE_VALUE (*s) == spec)
878 *s = TREE_CHAIN (*s);
885 /* Like register_specialization, but for local declarations. FN is
886 the function in which we are registering SPEC, an instantiation of
890 register_local_specialization (spec, tmpl, fn)
895 DECL_TEMPLATE_SPECIALIZATIONS (tmpl)
896 = tree_cons (fn, spec, DECL_TEMPLATE_SPECIALIZATIONS (tmpl));
901 /* Print the list of candidate FNS in an error message. */
904 print_candidates (fns)
909 const char *str = "candidates are:";
911 for (fn = fns; fn != NULL_TREE; fn = TREE_CHAIN (fn))
915 for (f = TREE_VALUE (fn); f; f = OVL_NEXT (f))
916 cp_error_at ("%s %+#D", str, OVL_CURRENT (f));
921 /* Returns the template (one of the functions given by TEMPLATE_ID)
922 which can be specialized to match the indicated DECL with the
923 explicit template args given in TEMPLATE_ID. The DECL may be
924 NULL_TREE if none is available. In that case, the functions in
925 TEMPLATE_ID are non-members.
927 If NEED_MEMBER_TEMPLATE is non-zero the function is known to be a
928 specialization of a member template.
930 The template args (those explicitly specified and those deduced)
931 are output in a newly created vector *TARGS_OUT.
933 If it is impossible to determine the result, an error message is
934 issued. The error_mark_node is returned to indicate failure. */
937 determine_specialization (template_id, decl, targs_out,
938 need_member_template)
942 int need_member_template;
947 tree candidates = NULL_TREE;
948 tree templates = NULL_TREE;
950 *targs_out = NULL_TREE;
952 if (template_id == error_mark_node)
953 return error_mark_node;
955 fns = TREE_OPERAND (template_id, 0);
956 explicit_targs = TREE_OPERAND (template_id, 1);
958 if (fns == error_mark_node)
959 return error_mark_node;
961 /* Check for baselinks. */
962 if (BASELINK_P (fns))
963 fns = TREE_VALUE (fns);
965 if (!is_overloaded_fn (fns))
967 cp_error ("`%D' is not a function template", fns);
968 return error_mark_node;
971 for (; fns; fns = OVL_NEXT (fns))
975 tree fn = OVL_CURRENT (fns);
977 if (TREE_CODE (fn) == TEMPLATE_DECL)
978 /* DECL might be a specialization of FN. */
980 else if (need_member_template)
981 /* FN is an ordinary member function, and we need a
982 specialization of a member template. */
984 else if (TREE_CODE (fn) != FUNCTION_DECL)
985 /* We can get IDENTIFIER_NODEs here in certain erroneous
988 else if (!DECL_FUNCTION_MEMBER_P (fn))
989 /* This is just an ordinary non-member function. Nothing can
990 be a specialization of that. */
996 /* This is an ordinary member function. However, since
997 we're here, we can assume it's enclosing class is a
998 template class. For example,
1000 template <typename T> struct S { void f(); };
1001 template <> void S<int>::f() {}
1003 Here, S<int>::f is a non-template, but S<int> is a
1004 template class. If FN has the same type as DECL, we
1005 might be in business. */
1006 if (!same_type_p (TREE_TYPE (TREE_TYPE (decl)),
1007 TREE_TYPE (TREE_TYPE (fn))))
1008 /* The return types differ. */
1011 /* Adjust the type of DECL in case FN is a static member. */
1012 decl_arg_types = TYPE_ARG_TYPES (TREE_TYPE (decl));
1013 if (DECL_STATIC_FUNCTION_P (fn)
1014 && DECL_NONSTATIC_MEMBER_FUNCTION_P (decl))
1015 decl_arg_types = TREE_CHAIN (decl_arg_types);
1017 if (compparms (TYPE_ARG_TYPES (TREE_TYPE (fn)),
1020 candidates = tree_cons (NULL_TREE, fn, candidates);
1025 /* See whether this function might be a specialization of this
1027 targs = get_bindings (tmpl, decl, explicit_targs);
1030 /* We cannot deduce template arguments that when used to
1031 specialize TMPL will produce DECL. */
1034 /* Save this template, and the arguments deduced. */
1035 templates = tree_cons (targs, tmpl, templates);
1038 if (templates && TREE_CHAIN (templates))
1044 It is possible for a specialization with a given function
1045 signature to be instantiated from more than one function
1046 template. In such cases, explicit specification of the
1047 template arguments must be used to uniquely identify the
1048 function template specialization being specialized.
1050 Note that here, there's no suggestion that we're supposed to
1051 determine which of the candidate templates is most
1052 specialized. However, we, also have:
1056 Partial ordering of overloaded function template
1057 declarations is used in the following contexts to select
1058 the function template to which a function template
1059 specialization refers:
1061 -- when an explicit specialization refers to a function
1064 So, we do use the partial ordering rules, at least for now.
1065 This extension can only serve to make illegal programs legal,
1066 so it's safe. And, there is strong anecdotal evidence that
1067 the committee intended the partial ordering rules to apply;
1068 the EDG front-end has that behavior, and John Spicer claims
1069 that the committee simply forgot to delete the wording in
1070 [temp.expl.spec]. */
1071 tree tmpl = most_specialized (templates, decl, explicit_targs);
1072 if (tmpl && tmpl != error_mark_node)
1074 targs = get_bindings (tmpl, decl, explicit_targs);
1075 templates = tree_cons (targs, tmpl, NULL_TREE);
1079 if (templates == NULL_TREE && candidates == NULL_TREE)
1081 cp_error_at ("template-id `%D' for `%+D' does not match any template declaration",
1083 return error_mark_node;
1085 else if ((templates && TREE_CHAIN (templates))
1086 || (candidates && TREE_CHAIN (candidates))
1087 || (templates && candidates))
1089 cp_error_at ("ambiguous template specialization `%D' for `%+D'",
1091 chainon (candidates, templates);
1092 print_candidates (candidates);
1093 return error_mark_node;
1096 /* We have one, and exactly one, match. */
1099 /* It was a specialization of an ordinary member function in a
1101 *targs_out = copy_node (DECL_TI_ARGS (TREE_VALUE (candidates)));
1102 return DECL_TI_TEMPLATE (TREE_VALUE (candidates));
1105 /* It was a specialization of a template. */
1106 targs = DECL_TI_ARGS (DECL_RESULT (TREE_VALUE (templates)));
1107 if (TMPL_ARGS_HAVE_MULTIPLE_LEVELS (targs))
1109 *targs_out = copy_node (targs);
1110 SET_TMPL_ARGS_LEVEL (*targs_out,
1111 TMPL_ARGS_DEPTH (*targs_out),
1112 TREE_PURPOSE (templates));
1115 *targs_out = TREE_PURPOSE (templates);
1116 return TREE_VALUE (templates);
1119 /* Check to see if the function just declared, as indicated in
1120 DECLARATOR, and in DECL, is a specialization of a function
1121 template. We may also discover that the declaration is an explicit
1122 instantiation at this point.
1124 Returns DECL, or an equivalent declaration that should be used
1125 instead if all goes well. Issues an error message if something is
1126 amiss. Returns error_mark_node if the error is not easily
1129 FLAGS is a bitmask consisting of the following flags:
1131 2: The function has a definition.
1132 4: The function is a friend.
1134 The TEMPLATE_COUNT is the number of references to qualifying
1135 template classes that appeared in the name of the function. For
1138 template <class T> struct S { void f(); };
1141 the TEMPLATE_COUNT would be 1. However, explicitly specialized
1142 classes are not counted in the TEMPLATE_COUNT, so that in
1144 template <class T> struct S {};
1145 template <> struct S<int> { void f(); }
1146 template <> void S<int>::f();
1148 the TEMPLATE_COUNT would be 0. (Note that this declaration is
1149 illegal; there should be no template <>.)
1151 If the function is a specialization, it is marked as such via
1152 DECL_TEMPLATE_SPECIALIZATION. Furthermore, its DECL_TEMPLATE_INFO
1153 is set up correctly, and it is added to the list of specializations
1154 for that template. */
1157 check_explicit_specialization (declarator, decl, template_count, flags)
1163 int have_def = flags & 2;
1164 int is_friend = flags & 4;
1165 int specialization = 0;
1166 int explicit_instantiation = 0;
1167 int member_specialization = 0;
1169 tree ctype = DECL_CLASS_CONTEXT (decl);
1170 tree dname = DECL_NAME (decl);
1172 if (processing_specialization)
1174 /* The last template header was of the form template <>. */
1176 if (template_header_count > template_count)
1178 /* There were more template headers than qualifying template
1180 if (template_header_count - template_count > 1)
1181 /* There shouldn't be that many template parameter lists.
1182 There can be at most one parameter list for every
1183 qualifying class, plus one for the function itself. */
1184 cp_error ("too many template parameter lists in declaration of `%D'", decl);
1186 SET_DECL_TEMPLATE_SPECIALIZATION (decl);
1188 member_specialization = 1;
1192 else if (template_header_count == template_count)
1194 /* The counts are equal. So, this might be a
1195 specialization, but it is not a specialization of a
1196 member template. It might be something like
1198 template <class T> struct S {
1202 void S<int>::f(int i) {} */
1204 SET_DECL_TEMPLATE_SPECIALIZATION (decl);
1208 /* This cannot be an explicit specialization. There are not
1209 enough headers for all of the qualifying classes. For
1210 example, we might have:
1213 void S<int>::T<char>::f();
1215 But, we're missing another template <>. */
1216 cp_error("too few template parameter lists in declaration of `%D'", decl);
1220 else if (processing_explicit_instantiation)
1222 if (template_header_count)
1223 cp_error ("template parameter list used in explicit instantiation");
1226 cp_error ("definition provided for explicit instantiation");
1228 explicit_instantiation = 1;
1230 else if (ctype != NULL_TREE
1231 && !TYPE_BEING_DEFINED (ctype)
1232 && CLASSTYPE_TEMPLATE_INSTANTIATION (ctype)
1235 /* This case catches outdated code that looks like this:
1237 template <class T> struct S { void f(); };
1238 void S<int>::f() {} // Missing template <>
1240 We disable this check when the type is being defined to
1241 avoid complaining about default compiler-generated
1242 constructors, destructors, and assignment operators.
1243 Since the type is an instantiation, not a specialization,
1244 these are the only functions that can be defined before
1245 the class is complete. */
1248 template <class T> void S<int>::f() {}
1250 if (template_header_count)
1252 cp_error ("template parameters specified in specialization");
1258 ("explicit specialization not preceded by `template <>'");
1260 SET_DECL_TEMPLATE_SPECIALIZATION (decl);
1262 else if (TREE_CODE (declarator) == TEMPLATE_ID_EXPR)
1265 /* This could be something like:
1267 template <class T> void f(T);
1268 class S { friend void f<>(int); } */
1272 /* This case handles bogus declarations like template <>
1273 template <class T> void f<int>(); */
1275 cp_error ("template-id `%D' in declaration of primary template",
1281 if (specialization || member_specialization)
1283 tree t = TYPE_ARG_TYPES (TREE_TYPE (decl));
1284 for (; t; t = TREE_CHAIN (t))
1285 if (TREE_PURPOSE (t))
1288 ("default argument specified in explicit specialization");
1291 if (current_lang_name == lang_name_c)
1292 cp_error ("template specialization with C linkage");
1295 if (specialization || member_specialization || explicit_instantiation)
1297 tree tmpl = NULL_TREE;
1298 tree targs = NULL_TREE;
1300 /* Make sure that the declarator is a TEMPLATE_ID_EXPR. */
1301 if (TREE_CODE (declarator) != TEMPLATE_ID_EXPR)
1305 my_friendly_assert (TREE_CODE (declarator) == IDENTIFIER_NODE,
1308 fns = IDENTIFIER_NAMESPACE_VALUE (dname);
1313 lookup_template_function (fns, NULL_TREE);
1316 if (declarator == error_mark_node)
1317 return error_mark_node;
1319 if (ctype != NULL_TREE && TYPE_BEING_DEFINED (ctype))
1321 if (!explicit_instantiation)
1322 /* A specialization in class scope. This is illegal,
1323 but the error will already have been flagged by
1324 check_specialization_scope. */
1325 return error_mark_node;
1328 /* It's not legal to write an explicit instantiation in
1331 class C { template void f(); }
1333 This case is caught by the parser. However, on
1336 template class C { void f(); };
1338 (which is illegal) we can get here. The error will be
1345 else if (TREE_CODE (TREE_OPERAND (declarator, 0)) == LOOKUP_EXPR)
1347 /* A friend declaration. We can't do much, because we don't
1348 know what this resolves to, yet. */
1349 my_friendly_assert (is_friend != 0, 0);
1350 my_friendly_assert (!explicit_instantiation, 0);
1351 SET_DECL_IMPLICIT_INSTANTIATION (decl);
1354 else if (ctype != NULL_TREE
1355 && (TREE_CODE (TREE_OPERAND (declarator, 0)) ==
1358 /* Find the list of functions in ctype that have the same
1359 name as the declared function. */
1360 tree name = TREE_OPERAND (declarator, 0);
1361 tree fns = NULL_TREE;
1364 if (name == constructor_name (ctype)
1365 || name == constructor_name_full (ctype))
1367 int is_constructor = DECL_CONSTRUCTOR_P (decl);
1369 if (is_constructor ? !TYPE_HAS_CONSTRUCTOR (ctype)
1370 : !TYPE_HAS_DESTRUCTOR (ctype))
1372 /* From [temp.expl.spec]:
1374 If such an explicit specialization for the member
1375 of a class template names an implicitly-declared
1376 special member function (clause _special_), the
1377 program is ill-formed.
1379 Similar language is found in [temp.explicit]. */
1380 cp_error ("specialization of implicitly-declared special member function");
1381 return error_mark_node;
1384 name = is_constructor ? ctor_identifier : dtor_identifier;
1387 if (!IDENTIFIER_TYPENAME_P (name))
1389 idx = lookup_fnfields_1 (ctype, name);
1391 fns = TREE_VEC_ELT (CLASSTYPE_METHOD_VEC (ctype), idx);
1397 /* For a type-conversion operator, we cannot do a
1398 name-based lookup. We might be looking for `operator
1399 int' which will be a specialization of `operator T'.
1400 So, we find *all* the conversion operators, and then
1401 select from them. */
1404 methods = CLASSTYPE_METHOD_VEC (ctype);
1406 for (idx = 2; idx < TREE_VEC_LENGTH (methods); ++idx)
1408 tree ovl = TREE_VEC_ELT (methods, idx);
1410 if (!ovl || !DECL_CONV_FN_P (OVL_CURRENT (ovl)))
1411 /* There are no more conversion functions. */
1414 /* Glue all these conversion functions together
1415 with those we already have. */
1416 for (; ovl; ovl = OVL_NEXT (ovl))
1417 fns = ovl_cons (OVL_CURRENT (ovl), fns);
1421 if (fns == NULL_TREE)
1423 cp_error ("no member function `%D' declared in `%T'",
1425 return error_mark_node;
1428 TREE_OPERAND (declarator, 0) = fns;
1431 /* Figure out what exactly is being specialized at this point.
1432 Note that for an explicit instantiation, even one for a
1433 member function, we cannot tell apriori whether the
1434 instantiation is for a member template, or just a member
1435 function of a template class. Even if a member template is
1436 being instantiated, the member template arguments may be
1437 elided if they can be deduced from the rest of the
1439 tmpl = determine_specialization (declarator, decl,
1441 member_specialization);
1443 if (!tmpl || tmpl == error_mark_node)
1444 /* We couldn't figure out what this declaration was
1446 return error_mark_node;
1449 tree gen_tmpl = most_general_template (tmpl);
1451 if (explicit_instantiation)
1453 /* We don't set DECL_EXPLICIT_INSTANTIATION here; that
1454 is done by do_decl_instantiation later. */
1456 int arg_depth = TMPL_ARGS_DEPTH (targs);
1457 int parm_depth = TMPL_PARMS_DEPTH (DECL_TEMPLATE_PARMS (tmpl));
1459 if (arg_depth > parm_depth)
1461 /* If TMPL is not the most general template (for
1462 example, if TMPL is a friend template that is
1463 injected into namespace scope), then there will
1464 be too many levels fo TARGS. Remove some of them
1469 new_targs = make_tree_vec (parm_depth);
1470 for (i = arg_depth - parm_depth; i < arg_depth; ++i)
1471 TREE_VEC_ELT (new_targs, i - (arg_depth - parm_depth))
1472 = TREE_VEC_ELT (targs, i);
1476 decl = instantiate_template (tmpl, targs);
1480 /* If we though that the DECL was a member function, but it
1481 turns out to be specializing a static member function,
1482 make DECL a static member function as well. */
1483 if (DECL_STATIC_FUNCTION_P (tmpl)
1484 && DECL_NONSTATIC_MEMBER_FUNCTION_P (decl))
1486 revert_static_member_fn (&decl, 0, 0);
1487 last_function_parms = TREE_CHAIN (last_function_parms);
1490 /* Set up the DECL_TEMPLATE_INFO for DECL. */
1491 DECL_TEMPLATE_INFO (decl) = tree_cons (tmpl, targs, NULL_TREE);
1493 /* Mangle the function name appropriately. Note that we do
1494 not mangle specializations of non-template member
1495 functions of template classes, e.g. with
1497 template <class T> struct S { void f(); }
1499 and given the specialization
1501 template <> void S<int>::f() {}
1503 we do not mangle S<int>::f() here. That's because it's
1504 just an ordinary member function and doesn't need special
1505 treatment. We do this here so that the ordinary,
1506 non-template, name-mangling algorith will not be used
1508 if ((is_member_template (tmpl) || ctype == NULL_TREE)
1509 && name_mangling_version >= 1)
1510 set_mangled_name_for_template_decl (decl);
1512 if (is_friend && !have_def)
1513 /* This is not really a declaration of a specialization.
1514 It's just the name of an instantiation. But, it's not
1515 a request for an instantiation, either. */
1516 SET_DECL_IMPLICIT_INSTANTIATION (decl);
1518 /* Register this specialization so that we can find it
1520 decl = register_specialization (decl, gen_tmpl, targs);
1527 /* TYPE is being declared. Verify that the use of template headers
1528 and such is reasonable. Issue error messages if not. */
1531 maybe_check_template_type (type)
1534 if (template_header_count)
1536 /* We are in the scope of some `template <...>' header. */
1539 = template_class_depth_real (TYPE_CONTEXT (type),
1540 /*count_specializations=*/1);
1542 if (template_header_count <= context_depth)
1543 /* This is OK; the template headers are for the context. We
1544 are actually too lenient here; like
1545 check_explicit_specialization we should consider the number
1546 of template types included in the actual declaration. For
1549 template <class T> struct S {
1550 template <class U> template <class V>
1556 template <class T> struct S {
1557 template <class U> struct I;
1560 template <class T> template <class U.
1565 else if (template_header_count > context_depth + 1)
1566 /* There are two many template parameter lists. */
1567 cp_error ("too many template parameter lists in declaration of `%T'", type);
1571 /* Returns 1 iff PARMS1 and PARMS2 are identical sets of template
1572 parameters. These are represented in the same format used for
1573 DECL_TEMPLATE_PARMS. */
1575 int comp_template_parms (parms1, parms2)
1582 if (parms1 == parms2)
1585 for (p1 = parms1, p2 = parms2;
1586 p1 != NULL_TREE && p2 != NULL_TREE;
1587 p1 = TREE_CHAIN (p1), p2 = TREE_CHAIN (p2))
1589 tree t1 = TREE_VALUE (p1);
1590 tree t2 = TREE_VALUE (p2);
1593 my_friendly_assert (TREE_CODE (t1) == TREE_VEC, 0);
1594 my_friendly_assert (TREE_CODE (t2) == TREE_VEC, 0);
1596 if (TREE_VEC_LENGTH (t1) != TREE_VEC_LENGTH (t2))
1599 for (i = 0; i < TREE_VEC_LENGTH (t2); ++i)
1601 tree parm1 = TREE_VALUE (TREE_VEC_ELT (t1, i));
1602 tree parm2 = TREE_VALUE (TREE_VEC_ELT (t2, i));
1604 if (TREE_CODE (parm1) != TREE_CODE (parm2))
1607 if (TREE_CODE (parm1) == TEMPLATE_TYPE_PARM)
1609 else if (!same_type_p (TREE_TYPE (parm1), TREE_TYPE (parm2)))
1614 if ((p1 != NULL_TREE) != (p2 != NULL_TREE))
1615 /* One set of parameters has more parameters lists than the
1622 /* Complain if DECL shadows a template parameter.
1624 [temp.local]: A template-parameter shall not be redeclared within its
1625 scope (including nested scopes). */
1628 check_template_shadow (decl)
1633 /* If we're not in a template, we can't possibly shadow a template
1635 if (!current_template_parms)
1638 /* Figure out what we're shadowing. */
1639 if (TREE_CODE (decl) == OVERLOAD)
1640 decl = OVL_CURRENT (decl);
1641 olddecl = IDENTIFIER_VALUE (DECL_NAME (decl));
1643 /* If there's no previous binding for this name, we're not shadowing
1644 anything, let alone a template parameter. */
1648 /* If we're not shadowing a template parameter, we're done. Note
1649 that OLDDECL might be an OVERLOAD (or perhaps even an
1650 ERROR_MARK), so we can't just blithely assume it to be a _DECL
1652 if (TREE_CODE_CLASS (TREE_CODE (olddecl)) != 'd'
1653 || !DECL_TEMPLATE_PARM_P (olddecl))
1656 /* We check for decl != olddecl to avoid bogus errors for using a
1657 name inside a class. We check TPFI to avoid duplicate errors for
1658 inline member templates. */
1660 || TEMPLATE_PARMS_FOR_INLINE (current_template_parms))
1663 cp_error_at ("declaration of `%#D'", decl);
1664 cp_error_at (" shadows template parm `%#D'", olddecl);
1667 /* Return a new TEMPLATE_PARM_INDEX with the indicated INDEX, LEVEL,
1668 ORIG_LEVEL, DECL, and TYPE. */
1671 build_template_parm_index (index, level, orig_level, decl, type)
1678 tree t = make_node (TEMPLATE_PARM_INDEX);
1679 TEMPLATE_PARM_IDX (t) = index;
1680 TEMPLATE_PARM_LEVEL (t) = level;
1681 TEMPLATE_PARM_ORIG_LEVEL (t) = orig_level;
1682 TEMPLATE_PARM_DECL (t) = decl;
1683 TREE_TYPE (t) = type;
1688 /* Return a TEMPLATE_PARM_INDEX, similar to INDEX, but whose
1689 TEMPLATE_PARM_LEVEL has been decreased by LEVELS. If such a
1690 TEMPLATE_PARM_INDEX already exists, it is returned; otherwise, a
1691 new one is created. */
1694 reduce_template_parm_level (index, type, levels)
1699 if (TEMPLATE_PARM_DESCENDANTS (index) == NULL_TREE
1700 || (TEMPLATE_PARM_LEVEL (TEMPLATE_PARM_DESCENDANTS (index))
1701 != TEMPLATE_PARM_LEVEL (index) - levels))
1704 = build_decl (TREE_CODE (TEMPLATE_PARM_DECL (index)),
1705 DECL_NAME (TEMPLATE_PARM_DECL (index)),
1708 = build_template_parm_index (TEMPLATE_PARM_IDX (index),
1709 TEMPLATE_PARM_LEVEL (index) - levels,
1710 TEMPLATE_PARM_ORIG_LEVEL (index),
1712 TEMPLATE_PARM_DESCENDANTS (index) = t;
1714 /* Template template parameters need this. */
1715 DECL_TEMPLATE_PARMS (decl)
1716 = DECL_TEMPLATE_PARMS (TEMPLATE_PARM_DECL (index));
1719 return TEMPLATE_PARM_DESCENDANTS (index);
1722 /* Process information from new template parameter NEXT and append it to the
1723 LIST being built. */
1726 process_template_parm (list, next)
1735 my_friendly_assert (TREE_CODE (parm) == TREE_LIST, 259);
1736 defval = TREE_PURPOSE (parm);
1737 parm = TREE_VALUE (parm);
1738 is_type = TREE_PURPOSE (parm) == class_type_node;
1742 tree p = TREE_VALUE (tree_last (list));
1744 if (TREE_CODE (p) == TYPE_DECL)
1745 idx = TEMPLATE_TYPE_IDX (TREE_TYPE (p));
1746 else if (TREE_CODE (p) == TEMPLATE_DECL)
1747 idx = TEMPLATE_TYPE_IDX (TREE_TYPE (DECL_TEMPLATE_RESULT (p)));
1749 idx = TEMPLATE_PARM_IDX (DECL_INITIAL (p));
1757 my_friendly_assert (TREE_CODE (TREE_PURPOSE (parm)) == TREE_LIST, 260);
1758 /* is a const-param */
1759 parm = grokdeclarator (TREE_VALUE (parm), TREE_PURPOSE (parm),
1760 PARM, 0, NULL_TREE);
1764 The top-level cv-qualifiers on the template-parameter are
1765 ignored when determining its type. */
1766 TREE_TYPE (parm) = TYPE_MAIN_VARIANT (TREE_TYPE (parm));
1768 /* A template parameter is not modifiable. */
1769 TREE_READONLY (parm) = 1;
1770 if (IS_AGGR_TYPE (TREE_TYPE (parm))
1771 && TREE_CODE (TREE_TYPE (parm)) != TEMPLATE_TYPE_PARM
1772 && TREE_CODE (TREE_TYPE (parm)) != TYPENAME_TYPE)
1774 cp_error ("`%#T' is not a valid type for a template constant parameter",
1776 if (DECL_NAME (parm) == NULL_TREE)
1777 error (" a template type parameter must begin with `class' or `typename'");
1778 TREE_TYPE (parm) = void_type_node;
1781 && (TREE_CODE (TREE_TYPE (parm)) == REAL_TYPE
1782 || TREE_CODE (TREE_TYPE (parm)) == COMPLEX_TYPE))
1783 cp_pedwarn ("`%T' is not a valid type for a template constant parameter",
1785 decl = build_decl (CONST_DECL, DECL_NAME (parm), TREE_TYPE (parm));
1786 DECL_INITIAL (parm) = DECL_INITIAL (decl)
1787 = build_template_parm_index (idx, processing_template_decl,
1788 processing_template_decl,
1789 decl, TREE_TYPE (parm));
1794 parm = TREE_VALUE (parm);
1796 if (parm && TREE_CODE (parm) == TEMPLATE_DECL)
1798 t = make_aggr_type (TEMPLATE_TEMPLATE_PARM);
1799 /* This is for distinguishing between real templates and template
1800 template parameters */
1801 TREE_TYPE (parm) = t;
1802 TREE_TYPE (DECL_TEMPLATE_RESULT (parm)) = t;
1807 t = make_aggr_type (TEMPLATE_TYPE_PARM);
1808 /* parm is either IDENTIFIER_NODE or NULL_TREE */
1809 decl = build_decl (TYPE_DECL, parm, t);
1812 TYPE_NAME (t) = decl;
1813 TYPE_STUB_DECL (t) = decl;
1815 TEMPLATE_TYPE_PARM_INDEX (t)
1816 = build_template_parm_index (idx, processing_template_decl,
1817 processing_template_decl,
1818 decl, TREE_TYPE (parm));
1820 SET_DECL_ARTIFICIAL (decl);
1821 SET_DECL_TEMPLATE_PARM_P (decl);
1823 parm = build_tree_list (defval, parm);
1824 return chainon (list, parm);
1827 /* The end of a template parameter list has been reached. Process the
1828 tree list into a parameter vector, converting each parameter into a more
1829 useful form. Type parameters are saved as IDENTIFIER_NODEs, and others
1833 end_template_parm_list (parms)
1838 tree saved_parmlist = make_tree_vec (list_length (parms));
1840 current_template_parms
1841 = tree_cons (build_int_2 (0, processing_template_decl),
1842 saved_parmlist, current_template_parms);
1844 for (parm = parms, nparms = 0;
1846 parm = TREE_CHAIN (parm), nparms++)
1847 TREE_VEC_ELT (saved_parmlist, nparms) = parm;
1849 --processing_template_parmlist;
1851 return saved_parmlist;
1854 /* end_template_decl is called after a template declaration is seen. */
1857 end_template_decl ()
1859 reset_specialization ();
1861 if (! processing_template_decl)
1864 /* This matches the pushlevel in begin_template_parm_list. */
1867 --processing_template_decl;
1868 current_template_parms = TREE_CHAIN (current_template_parms);
1869 (void) get_pending_sizes (); /* Why? */
1872 /* Given a template argument vector containing the template PARMS.
1873 The innermost PARMS are given first. */
1876 current_template_args ()
1879 tree args = NULL_TREE;
1880 int length = TMPL_PARMS_DEPTH (current_template_parms);
1883 /* If there is only one level of template parameters, we do not
1884 create a TREE_VEC of TREE_VECs. Instead, we return a single
1885 TREE_VEC containing the arguments. */
1887 args = make_tree_vec (length);
1889 for (header = current_template_parms; header; header = TREE_CHAIN (header))
1891 tree a = copy_node (TREE_VALUE (header));
1894 TREE_TYPE (a) = NULL_TREE;
1895 for (i = TREE_VEC_LENGTH (a) - 1; i >= 0; --i)
1897 tree t = TREE_VEC_ELT (a, i);
1899 /* T will be a list if we are called from within a
1900 begin/end_template_parm_list pair, but a vector directly
1901 if within a begin/end_member_template_processing pair. */
1902 if (TREE_CODE (t) == TREE_LIST)
1906 if (TREE_CODE (t) == TYPE_DECL
1907 || TREE_CODE (t) == TEMPLATE_DECL)
1910 t = DECL_INITIAL (t);
1911 TREE_VEC_ELT (a, i) = t;
1916 TREE_VEC_ELT (args, --l) = a;
1924 /* Return a TEMPLATE_DECL corresponding to DECL, using the indicated
1925 template PARMS. Used by push_template_decl below. */
1928 build_template_decl (decl, parms)
1932 tree tmpl = build_lang_decl (TEMPLATE_DECL, DECL_NAME (decl), NULL_TREE);
1933 DECL_TEMPLATE_PARMS (tmpl) = parms;
1934 DECL_CONTEXT (tmpl) = DECL_CONTEXT (decl);
1935 if (DECL_LANG_SPECIFIC (decl))
1937 DECL_VIRTUAL_CONTEXT (tmpl) = DECL_VIRTUAL_CONTEXT (decl);
1938 DECL_STATIC_FUNCTION_P (tmpl) = DECL_STATIC_FUNCTION_P (decl);
1939 DECL_CONSTRUCTOR_P (tmpl) = DECL_CONSTRUCTOR_P (decl);
1940 DECL_NONCONVERTING_P (tmpl) = DECL_NONCONVERTING_P (decl);
1946 struct template_parm_data
1948 /* The level of the template parameters we are currently
1952 /* The index of the specialization argument we are currently
1956 /* An array whose size is the number of template parameters. The
1957 elements are non-zero if the parameter has been used in any one
1958 of the arguments processed so far. */
1961 /* An array whose size is the number of template arguments. The
1962 elements are non-zero if the argument makes use of template
1963 parameters of this level. */
1964 int* arg_uses_template_parms;
1967 /* Subroutine of push_template_decl used to see if each template
1968 parameter in a partial specialization is used in the explicit
1969 argument list. If T is of the LEVEL given in DATA (which is
1970 treated as a template_parm_data*), then DATA->PARMS is marked
1974 mark_template_parm (t, data)
1980 struct template_parm_data* tpd = (struct template_parm_data*) data;
1982 if (TREE_CODE (t) == TEMPLATE_PARM_INDEX)
1984 level = TEMPLATE_PARM_LEVEL (t);
1985 idx = TEMPLATE_PARM_IDX (t);
1989 level = TEMPLATE_TYPE_LEVEL (t);
1990 idx = TEMPLATE_TYPE_IDX (t);
1993 if (level == tpd->level)
1995 tpd->parms[idx] = 1;
1996 tpd->arg_uses_template_parms[tpd->current_arg] = 1;
1999 /* Return zero so that for_each_template_parm will continue the
2000 traversal of the tree; we want to mark *every* template parm. */
2004 /* Process the partial specialization DECL. */
2007 process_partial_specialization (decl)
2010 tree type = TREE_TYPE (decl);
2011 tree maintmpl = CLASSTYPE_TI_TEMPLATE (type);
2012 tree specargs = CLASSTYPE_TI_ARGS (type);
2013 tree inner_args = innermost_args (specargs);
2014 tree inner_parms = INNERMOST_TEMPLATE_PARMS (current_template_parms);
2015 tree main_inner_parms = DECL_INNERMOST_TEMPLATE_PARMS (maintmpl);
2016 int nargs = TREE_VEC_LENGTH (inner_args);
2017 int ntparms = TREE_VEC_LENGTH (inner_parms);
2019 int did_error_intro = 0;
2020 struct template_parm_data tpd;
2021 struct template_parm_data tpd2;
2023 /* We check that each of the template parameters given in the
2024 partial specialization is used in the argument list to the
2025 specialization. For example:
2027 template <class T> struct S;
2028 template <class T> struct S<T*>;
2030 The second declaration is OK because `T*' uses the template
2031 parameter T, whereas
2033 template <class T> struct S<int>;
2035 is no good. Even trickier is:
2046 The S2<T> declaration is actually illegal; it is a
2047 full-specialization. Of course,
2050 struct S2<T (*)(U)>;
2052 or some such would have been OK. */
2053 tpd.level = TMPL_PARMS_DEPTH (current_template_parms);
2054 tpd.parms = alloca (sizeof (int) * ntparms);
2055 bzero ((PTR) tpd.parms, sizeof (int) * ntparms);
2057 tpd.arg_uses_template_parms = alloca (sizeof (int) * nargs);
2058 bzero ((PTR) tpd.arg_uses_template_parms, sizeof (int) * nargs);
2059 for (i = 0; i < nargs; ++i)
2061 tpd.current_arg = i;
2062 for_each_template_parm (TREE_VEC_ELT (inner_args, i),
2063 &mark_template_parm,
2066 for (i = 0; i < ntparms; ++i)
2067 if (tpd.parms[i] == 0)
2069 /* One of the template parms was not used in the
2071 if (!did_error_intro)
2073 cp_error ("template parameters not used in partial specialization:");
2074 did_error_intro = 1;
2078 TREE_VALUE (TREE_VEC_ELT (inner_parms, i)));
2081 /* [temp.class.spec]
2083 The argument list of the specialization shall not be identical to
2084 the implicit argument list of the primary template. */
2085 if (comp_template_args (inner_args,
2086 innermost_args (CLASSTYPE_TI_ARGS (TREE_TYPE
2088 cp_error ("partial specialization `%T' does not specialize any template arguments", type);
2090 /* [temp.class.spec]
2092 A partially specialized non-type argument expression shall not
2093 involve template parameters of the partial specialization except
2094 when the argument expression is a simple identifier.
2096 The type of a template parameter corresponding to a specialized
2097 non-type argument shall not be dependent on a parameter of the
2099 my_friendly_assert (nargs == DECL_NTPARMS (maintmpl), 0);
2101 for (i = 0; i < nargs; ++i)
2103 tree arg = TREE_VEC_ELT (inner_args, i);
2104 if (/* These first two lines are the `non-type' bit. */
2105 TREE_CODE_CLASS (TREE_CODE (arg)) != 't'
2106 && TREE_CODE (arg) != TEMPLATE_DECL
2107 /* This next line is the `argument expression is not just a
2108 simple identifier' condition and also the `specialized
2109 non-type argument' bit. */
2110 && TREE_CODE (arg) != TEMPLATE_PARM_INDEX)
2112 if (tpd.arg_uses_template_parms[i])
2113 cp_error ("template argument `%E' involves template parameter(s)", arg);
2116 /* Look at the corresponding template parameter,
2117 marking which template parameters its type depends
2120 TREE_TYPE (TREE_VALUE (TREE_VEC_ELT (main_inner_parms,
2125 /* We haven't yet initialized TPD2. Do so now. */
2126 tpd2.arg_uses_template_parms
2127 = (int*) alloca (sizeof (int) * nargs);
2128 /* The number of parameters here is the number in the
2129 main template, which, as checked in the assertion
2131 tpd2.parms = (int*) alloca (sizeof (int) * nargs);
2133 TMPL_PARMS_DEPTH (DECL_TEMPLATE_PARMS (maintmpl));
2136 /* Mark the template parameters. But this time, we're
2137 looking for the template parameters of the main
2138 template, not in the specialization. */
2139 tpd2.current_arg = i;
2140 tpd2.arg_uses_template_parms[i] = 0;
2141 bzero ((PTR) tpd2.parms, sizeof (int) * nargs);
2142 for_each_template_parm (type,
2143 &mark_template_parm,
2146 if (tpd2.arg_uses_template_parms [i])
2148 /* The type depended on some template parameters.
2149 If they are fully specialized in the
2150 specialization, that's OK. */
2152 for (j = 0; j < nargs; ++j)
2153 if (tpd2.parms[j] != 0
2154 && tpd.arg_uses_template_parms [j])
2156 cp_error ("type `%T' of template argument `%E' depends on template parameter(s)",
2166 if (retrieve_specialization (maintmpl, specargs))
2167 /* We've already got this specialization. */
2170 DECL_TEMPLATE_SPECIALIZATIONS (maintmpl) = CLASSTYPE_TI_SPEC_INFO (type)
2171 = tree_cons (inner_args, inner_parms,
2172 DECL_TEMPLATE_SPECIALIZATIONS (maintmpl));
2173 TREE_TYPE (DECL_TEMPLATE_SPECIALIZATIONS (maintmpl)) = type;
2177 /* Check that a template declaration's use of default arguments is not
2178 invalid. Here, PARMS are the template parameters. IS_PRIMARY is
2179 non-zero if DECL is the thing declared by a primary template.
2180 IS_PARTIAL is non-zero if DECL is a partial specialization. */
2183 check_default_tmpl_args (decl, parms, is_primary, is_partial)
2190 int last_level_to_check;
2195 A default template-argument shall not be specified in a
2196 function template declaration or a function template definition, nor
2197 in the template-parameter-list of the definition of a member of a
2200 if (TREE_CODE (CP_DECL_CONTEXT (decl)) == FUNCTION_DECL)
2201 /* You can't have a function template declaration in a local
2202 scope, nor you can you define a member of a class template in a
2206 if (current_class_type
2207 && !TYPE_BEING_DEFINED (current_class_type)
2208 && DECL_LANG_SPECIFIC (decl)
2209 /* If this is either a friend defined in the scope of the class
2210 or a member function. */
2211 && ((DECL_CONTEXT (decl)
2212 && same_type_p (DECL_CONTEXT (decl), current_class_type))
2213 || (DECL_FRIEND_CONTEXT (decl)
2214 && same_type_p (DECL_FRIEND_CONTEXT (decl),
2215 current_class_type)))
2216 /* And, if it was a member function, it really was defined in
2217 the scope of the class. */
2218 && (!DECL_FUNCTION_MEMBER_P (decl) || DECL_DEFINED_IN_CLASS_P (decl)))
2219 /* We already checked these parameters when the template was
2220 declared, so there's no need to do it again now. This function
2221 was defined in class scope, but we're processing it's body now
2222 that the class is complete. */
2227 If a template-parameter has a default template-argument, all
2228 subsequent template-parameters shall have a default
2229 template-argument supplied. */
2230 for (parm_level = parms; parm_level; parm_level = TREE_CHAIN (parm_level))
2232 tree inner_parms = TREE_VALUE (parm_level);
2233 int ntparms = TREE_VEC_LENGTH (inner_parms);
2234 int seen_def_arg_p = 0;
2237 for (i = 0; i < ntparms; ++i)
2239 tree parm = TREE_VEC_ELT (inner_parms, i);
2240 if (TREE_PURPOSE (parm))
2242 else if (seen_def_arg_p)
2244 cp_error ("no default argument for `%D'", TREE_VALUE (parm));
2245 /* For better subsequent error-recovery, we indicate that
2246 there should have been a default argument. */
2247 TREE_PURPOSE (parm) = error_mark_node;
2252 if (TREE_CODE (decl) != TYPE_DECL || is_partial || !is_primary)
2253 /* For an ordinary class template, default template arguments are
2254 allowed at the innermost level, e.g.:
2255 template <class T = int>
2257 but, in a partial specialization, they're not allowed even
2258 there, as we have in [temp.class.spec]:
2260 The template parameter list of a specialization shall not
2261 contain default template argument values.
2263 So, for a partial specialization, or for a function template,
2264 we look at all of them. */
2267 /* But, for a primary class template that is not a partial
2268 specialization we look at all template parameters except the
2270 parms = TREE_CHAIN (parms);
2272 /* Figure out what error message to issue. */
2273 if (TREE_CODE (decl) == FUNCTION_DECL)
2274 msg = "default argument for template parameter in function template `%D'";
2275 else if (is_partial)
2276 msg = "default argument in partial specialization `%D'";
2278 msg = "default argument for template parameter for class enclosing `%D'";
2280 if (current_class_type && TYPE_BEING_DEFINED (current_class_type))
2281 /* If we're inside a class definition, there's no need to
2282 examine the parameters to the class itself. On the one
2283 hand, they will be checked when the class is defined, and,
2284 on the other, default arguments are legal in things like:
2285 template <class T = double>
2286 struct S { template <class U> void f(U); };
2287 Here the default argument for `S' has no bearing on the
2288 declaration of `f'. */
2289 last_level_to_check = template_class_depth (current_class_type) + 1;
2291 /* Check everything. */
2292 last_level_to_check = 0;
2294 for (parm_level = parms;
2295 parm_level && TMPL_PARMS_DEPTH (parm_level) >= last_level_to_check;
2296 parm_level = TREE_CHAIN (parm_level))
2298 tree inner_parms = TREE_VALUE (parm_level);
2302 ntparms = TREE_VEC_LENGTH (inner_parms);
2303 for (i = 0; i < ntparms; ++i)
2304 if (TREE_PURPOSE (TREE_VEC_ELT (inner_parms, i)))
2308 cp_error (msg, decl);
2312 /* Clear out the default argument so that we are not
2314 TREE_PURPOSE (TREE_VEC_ELT (inner_parms, i)) = NULL_TREE;
2317 /* At this point, if we're still interested in issuing messages,
2318 they must apply to classes surrounding the object declared. */
2320 msg = "default argument for template parameter for class enclosing `%D'";
2324 /* Creates a TEMPLATE_DECL for the indicated DECL using the template
2325 parameters given by current_template_args, or reuses a
2326 previously existing one, if appropriate. Returns the DECL, or an
2327 equivalent one, if it is replaced via a call to duplicate_decls.
2329 If IS_FRIEND is non-zero, DECL is a friend declaration. */
2332 push_template_decl_real (decl, is_friend)
2342 int new_template_p = 0;
2344 /* See if this is a partial specialization. */
2345 is_partial = (DECL_IMPLICIT_TYPEDEF_P (decl)
2346 && TREE_CODE (TREE_TYPE (decl)) != ENUMERAL_TYPE
2347 && CLASSTYPE_TEMPLATE_SPECIALIZATION (TREE_TYPE (decl)));
2349 is_friend |= (TREE_CODE (decl) == FUNCTION_DECL && DECL_FRIEND_P (decl));
2352 /* For a friend, we want the context of the friend function, not
2353 the type of which it is a friend. */
2354 ctx = DECL_CONTEXT (decl);
2355 else if (CP_DECL_CONTEXT (decl)
2356 && TREE_CODE (CP_DECL_CONTEXT (decl)) != NAMESPACE_DECL)
2357 /* In the case of a virtual function, we want the class in which
2359 ctx = CP_DECL_CONTEXT (decl);
2361 /* Otherwise, if we're currently definining some class, the DECL
2362 is assumed to be a member of the class. */
2363 ctx = current_scope ();
2365 if (ctx && TREE_CODE (ctx) == NAMESPACE_DECL)
2368 if (!DECL_CONTEXT (decl))
2369 DECL_CONTEXT (decl) = FROB_CONTEXT (current_namespace);
2371 /* See if this is a primary template. */
2372 primary = pseudo_global_level_p ();
2376 if (current_lang_name == lang_name_c)
2377 cp_error ("template with C linkage");
2378 else if (TREE_CODE (decl) == TYPE_DECL
2379 && ANON_AGGRNAME_P (DECL_NAME (decl)))
2380 cp_error ("template class without a name");
2381 else if ((DECL_IMPLICIT_TYPEDEF_P (decl)
2382 && CLASS_TYPE_P (TREE_TYPE (decl)))
2383 || (TREE_CODE (decl) == VAR_DECL && ctx && CLASS_TYPE_P (ctx))
2384 || TREE_CODE (decl) == FUNCTION_DECL)
2387 cp_error ("template declaration of `%#D'", decl);
2390 /* Check to see that the rules regarding the use of default
2391 arguments are not being violated. */
2392 check_default_tmpl_args (decl, current_template_parms,
2393 primary, is_partial);
2396 return process_partial_specialization (decl);
2398 args = current_template_args ();
2401 || TREE_CODE (ctx) == FUNCTION_DECL
2402 || TYPE_BEING_DEFINED (ctx)
2403 || (is_friend && !DECL_TEMPLATE_INFO (decl)))
2405 if (DECL_LANG_SPECIFIC (decl)
2406 && DECL_TEMPLATE_INFO (decl)
2407 && DECL_TI_TEMPLATE (decl))
2408 tmpl = DECL_TI_TEMPLATE (decl);
2409 /* If DECL is a TYPE_DECL for a class-template, then there won't
2410 be DECL_LANG_SPECIFIC. The information equivalent to
2411 DECL_TEMPLATE_INFO is found in TYPE_TEMPLATE_INFO instead. */
2412 else if (DECL_IMPLICIT_TYPEDEF_P (decl)
2413 && TYPE_TEMPLATE_INFO (TREE_TYPE (decl))
2414 && TYPE_TI_TEMPLATE (TREE_TYPE (decl)))
2416 /* Since a template declaration already existed for this
2417 class-type, we must be redeclaring it here. Make sure
2418 that the redeclaration is legal. */
2419 redeclare_class_template (TREE_TYPE (decl),
2420 current_template_parms);
2421 /* We don't need to create a new TEMPLATE_DECL; just use the
2422 one we already had. */
2423 tmpl = TYPE_TI_TEMPLATE (TREE_TYPE (decl));
2427 tmpl = build_template_decl (decl, current_template_parms);
2430 if (DECL_LANG_SPECIFIC (decl)
2431 && DECL_TEMPLATE_SPECIALIZATION (decl))
2433 /* A specialization of a member template of a template
2435 SET_DECL_TEMPLATE_SPECIALIZATION (tmpl);
2436 DECL_TEMPLATE_INFO (tmpl) = DECL_TEMPLATE_INFO (decl);
2437 DECL_TEMPLATE_INFO (decl) = NULL_TREE;
2443 tree a, t, current, parms;
2446 if (CLASSTYPE_TEMPLATE_INSTANTIATION (ctx))
2447 cp_error ("must specialize `%#T' before defining member `%#D'",
2449 if (TREE_CODE (decl) == TYPE_DECL)
2451 if ((IS_AGGR_TYPE_CODE (TREE_CODE (TREE_TYPE (decl)))
2452 || TREE_CODE (TREE_TYPE (decl)) == ENUMERAL_TYPE)
2453 && TYPE_TEMPLATE_INFO (TREE_TYPE (decl))
2454 && TYPE_TI_TEMPLATE (TREE_TYPE (decl)))
2455 tmpl = TYPE_TI_TEMPLATE (TREE_TYPE (decl));
2458 cp_error ("`%D' does not declare a template type", decl);
2462 else if (! DECL_TEMPLATE_INFO (decl))
2464 cp_error ("template definition of non-template `%#D'", decl);
2468 tmpl = DECL_TI_TEMPLATE (decl);
2470 if (is_member_template (tmpl)
2471 && DECL_FUNCTION_TEMPLATE_P (tmpl)
2472 && DECL_TEMPLATE_INFO (decl) && DECL_TI_ARGS (decl)
2473 && DECL_TEMPLATE_SPECIALIZATION (decl))
2477 /* The declaration is a specialization of a member
2478 template, declared outside the class. Therefore, the
2479 innermost template arguments will be NULL, so we
2480 replace them with the arguments determined by the
2481 earlier call to check_explicit_specialization. */
2482 args = DECL_TI_ARGS (decl);
2485 = build_template_decl (decl, current_template_parms);
2486 DECL_TEMPLATE_RESULT (new_tmpl) = decl;
2487 TREE_TYPE (new_tmpl) = TREE_TYPE (decl);
2488 DECL_TI_TEMPLATE (decl) = new_tmpl;
2489 SET_DECL_TEMPLATE_SPECIALIZATION (new_tmpl);
2490 DECL_TEMPLATE_INFO (new_tmpl)
2491 = tree_cons (tmpl, args, NULL_TREE);
2493 register_specialization (new_tmpl, tmpl, args);
2497 /* Make sure the template headers we got make sense. */
2499 parms = DECL_TEMPLATE_PARMS (tmpl);
2500 i = TMPL_PARMS_DEPTH (parms);
2501 if (TMPL_ARGS_DEPTH (args) != i)
2503 cp_error ("expected %d levels of template parms for `%#D', got %d",
2504 i, decl, TMPL_ARGS_DEPTH (args));
2507 for (current = decl; i > 0; --i, parms = TREE_CHAIN (parms))
2509 a = TMPL_ARGS_LEVEL (args, i);
2510 t = INNERMOST_TEMPLATE_PARMS (parms);
2512 if (TREE_VEC_LENGTH (t) != TREE_VEC_LENGTH (a))
2514 if (current == decl)
2515 cp_error ("got %d template parameters for `%#D'",
2516 TREE_VEC_LENGTH (a), decl);
2518 cp_error ("got %d template parameters for `%#T'",
2519 TREE_VEC_LENGTH (a), current);
2520 cp_error (" but %d required", TREE_VEC_LENGTH (t));
2523 /* Perhaps we should also check that the parms are used in the
2524 appropriate qualifying scopes in the declarator? */
2526 if (current == decl)
2529 current = TYPE_CONTEXT (current);
2533 DECL_TEMPLATE_RESULT (tmpl) = decl;
2534 TREE_TYPE (tmpl) = TREE_TYPE (decl);
2536 /* Push template declarations for global functions and types. Note
2537 that we do not try to push a global template friend declared in a
2538 template class; such a thing may well depend on the template
2539 parameters of the class. */
2540 if (new_template_p && !ctx
2541 && !(is_friend && template_class_depth (current_class_type) > 0))
2542 tmpl = pushdecl_namespace_level (tmpl);
2545 DECL_PRIMARY_TEMPLATE (tmpl) = tmpl;
2547 info = tree_cons (tmpl, args, NULL_TREE);
2549 if (DECL_IMPLICIT_TYPEDEF_P (decl))
2551 SET_TYPE_TEMPLATE_INFO (TREE_TYPE (tmpl), info);
2552 if ((!ctx || TREE_CODE (ctx) != FUNCTION_DECL)
2553 && TREE_CODE (TREE_TYPE (decl)) != ENUMERAL_TYPE)
2554 DECL_NAME (decl) = classtype_mangled_name (TREE_TYPE (decl));
2556 else if (DECL_LANG_SPECIFIC (decl))
2557 DECL_TEMPLATE_INFO (decl) = info;
2559 return DECL_TEMPLATE_RESULT (tmpl);
2563 push_template_decl (decl)
2566 return push_template_decl_real (decl, 0);
2569 /* Called when a class template TYPE is redeclared with the indicated
2570 template PARMS, e.g.:
2572 template <class T> struct S;
2573 template <class T> struct S {}; */
2576 redeclare_class_template (type, parms)
2584 if (!TYPE_TEMPLATE_INFO (type))
2586 cp_error ("`%T' is not a template type", type);
2590 tmpl = TYPE_TI_TEMPLATE (type);
2591 if (!PRIMARY_TEMPLATE_P (tmpl))
2592 /* The type is nested in some template class. Nothing to worry
2593 about here; there are no new template parameters for the nested
2597 parms = INNERMOST_TEMPLATE_PARMS (parms);
2598 tmpl_parms = DECL_INNERMOST_TEMPLATE_PARMS (tmpl);
2600 if (TREE_VEC_LENGTH (parms) != TREE_VEC_LENGTH (tmpl_parms))
2602 cp_error_at ("previous declaration `%D'", tmpl);
2603 cp_error ("used %d template parameter%s instead of %d",
2604 TREE_VEC_LENGTH (tmpl_parms),
2605 TREE_VEC_LENGTH (tmpl_parms) == 1 ? "" : "s",
2606 TREE_VEC_LENGTH (parms));
2610 for (i = 0; i < TREE_VEC_LENGTH (tmpl_parms); ++i)
2612 tree tmpl_parm = TREE_VALUE (TREE_VEC_ELT (tmpl_parms, i));
2613 tree parm = TREE_VALUE (TREE_VEC_ELT (parms, i));
2614 tree tmpl_default = TREE_PURPOSE (TREE_VEC_ELT (tmpl_parms, i));
2615 tree parm_default = TREE_PURPOSE (TREE_VEC_ELT (parms, i));
2617 if (TREE_CODE (tmpl_parm) != TREE_CODE (parm))
2619 cp_error_at ("template parameter `%#D'", tmpl_parm);
2620 cp_error ("redeclared here as `%#D'", parm);
2624 if (tmpl_default != NULL_TREE && parm_default != NULL_TREE)
2626 /* We have in [temp.param]:
2628 A template-parameter may not be given default arguments
2629 by two different declarations in the same scope. */
2630 cp_error ("redefinition of default argument for `%#D'", parm);
2631 cp_error_at (" original definition appeared here", tmpl_parm);
2635 if (parm_default != NULL_TREE)
2636 /* Update the previous template parameters (which are the ones
2637 that will really count) with the new default value. */
2638 TREE_PURPOSE (TREE_VEC_ELT (tmpl_parms, i)) = parm_default;
2639 else if (tmpl_default != NULL_TREE)
2640 /* Update the new parameters, too; they'll be used as the
2641 parameters for any members. */
2642 TREE_PURPOSE (TREE_VEC_ELT (parms, i)) = tmpl_default;
2646 /* Attempt to convert the non-type template parameter EXPR to the
2647 indicated TYPE. If the conversion is successful, return the
2648 converted value. If the conversion is unsuccesful, return
2649 NULL_TREE if we issued an error message, or error_mark_node if we
2650 did not. We issue error messages for out-and-out bad template
2651 parameters, but not simply because the conversion failed, since we
2652 might be just trying to do argument deduction. By the time this
2653 function is called, neither TYPE nor EXPR may make use of template
2657 convert_nontype_argument (type, expr)
2661 tree expr_type = TREE_TYPE (expr);
2663 /* A template-argument for a non-type, non-template
2664 template-parameter shall be one of:
2666 --an integral constant-expression of integral or enumeration
2669 --the name of a non-type template-parameter; or
2671 --the name of an object or function with external linkage,
2672 including function templates and function template-ids but
2673 excluding non-static class members, expressed as id-expression;
2676 --the address of an object or function with external linkage,
2677 including function templates and function template-ids but
2678 excluding non-static class members, expressed as & id-expression
2679 where the & is optional if the name refers to a function or
2682 --a pointer to member expressed as described in _expr.unary.op_. */
2684 /* An integral constant-expression can include const variables or
2685 enumerators. Simplify things by folding them to their values,
2686 unless we're about to bind the declaration to a reference
2688 if (INTEGRAL_TYPE_P (expr_type) && TREE_READONLY_DECL_P (expr)
2689 && TREE_CODE (type) != REFERENCE_TYPE)
2690 expr = decl_constant_value (expr);
2692 if (is_overloaded_fn (expr))
2693 /* OK for now. We'll check that it has external linkage later.
2694 Check this first since if expr_type is the unknown_type_node
2695 we would otherwise complain below. */
2697 else if (TYPE_PTRMEM_P (expr_type)
2698 || TYPE_PTRMEMFUNC_P (expr_type))
2700 if (TREE_CODE (expr) != PTRMEM_CST)
2703 else if (TYPE_PTR_P (expr_type)
2704 || TYPE_PTRMEM_P (expr_type)
2705 || TREE_CODE (expr_type) == ARRAY_TYPE
2706 || TREE_CODE (type) == REFERENCE_TYPE
2707 /* If expr is the address of an overloaded function, we
2708 will get the unknown_type_node at this point. */
2709 || expr_type == unknown_type_node)
2715 if (TREE_CODE (type) == REFERENCE_TYPE
2716 || TREE_CODE (expr_type) == ARRAY_TYPE)
2720 if (TREE_CODE (e) != ADDR_EXPR)
2723 cp_error ("`%E' is not a valid template argument", expr);
2724 if (TYPE_PTR_P (expr_type))
2726 if (TREE_CODE (TREE_TYPE (expr_type)) == FUNCTION_TYPE)
2727 cp_error ("it must be the address of a function with external linkage");
2729 cp_error ("it must be the address of an object with external linkage");
2731 else if (TYPE_PTRMEM_P (expr_type)
2732 || TYPE_PTRMEMFUNC_P (expr_type))
2733 cp_error ("it must be a pointer-to-member of the form `&X::Y'");
2738 referent = TREE_OPERAND (e, 0);
2739 STRIP_NOPS (referent);
2742 if (TREE_CODE (referent) == STRING_CST)
2744 cp_error ("string literal %E is not a valid template argument",
2746 error ("because it is the address of an object with static linkage");
2750 if (is_overloaded_fn (referent))
2751 /* We'll check that it has external linkage later. */
2753 else if (TREE_CODE (referent) != VAR_DECL)
2755 else if (!TREE_PUBLIC (referent))
2757 cp_error ("address of non-extern `%E' cannot be used as template argument", referent);
2758 return error_mark_node;
2761 else if (INTEGRAL_TYPE_P (expr_type)
2762 || TYPE_PTRMEM_P (expr_type)
2763 || TYPE_PTRMEMFUNC_P (expr_type)
2764 /* The next two are g++ extensions. */
2765 || TREE_CODE (expr_type) == REAL_TYPE
2766 || TREE_CODE (expr_type) == COMPLEX_TYPE)
2768 if (! TREE_CONSTANT (expr))
2771 cp_error ("non-constant `%E' cannot be used as template argument",
2778 cp_error ("object `%E' cannot be used as template argument", expr);
2782 switch (TREE_CODE (type))
2787 /* For a non-type template-parameter of integral or enumeration
2788 type, integral promotions (_conv.prom_) and integral
2789 conversions (_conv.integral_) are applied. */
2790 if (!INTEGRAL_TYPE_P (expr_type))
2791 return error_mark_node;
2793 /* It's safe to call digest_init in this case; we know we're
2794 just converting one integral constant expression to another. */
2795 expr = digest_init (type, expr, (tree*) 0);
2797 if (TREE_CODE (expr) != INTEGER_CST)
2798 /* Curiously, some TREE_CONSTANT integral expressions do not
2799 simplify to integer constants. For example, `3 % 0',
2800 remains a TRUNC_MOD_EXPR. */
2807 /* These are g++ extensions. */
2808 if (TREE_CODE (expr_type) != TREE_CODE (type))
2809 return error_mark_node;
2811 expr = digest_init (type, expr, (tree*) 0);
2813 if (TREE_CODE (expr) != REAL_CST)
2820 tree type_pointed_to = TREE_TYPE (type);
2822 if (TYPE_PTRMEM_P (type))
2826 /* For a non-type template-parameter of type pointer to data
2827 member, qualification conversions (_conv.qual_) are
2829 e = perform_qualification_conversions (type, expr);
2830 if (TREE_CODE (e) == NOP_EXPR)
2831 /* The call to perform_qualification_conversions will
2832 insert a NOP_EXPR over EXPR to do express conversion,
2833 if necessary. But, that will confuse us if we use
2834 this (converted) template parameter to instantiate
2835 another template; then the thing will not look like a
2836 valid template argument. So, just make a new
2837 constant, of the appropriate type. */
2838 e = make_ptrmem_cst (type, PTRMEM_CST_MEMBER (expr));
2841 else if (TREE_CODE (type_pointed_to) == FUNCTION_TYPE)
2843 /* For a non-type template-parameter of type pointer to
2844 function, only the function-to-pointer conversion
2845 (_conv.func_) is applied. If the template-argument
2846 represents a set of overloaded functions (or a pointer to
2847 such), the matching function is selected from the set
2852 if (TREE_CODE (expr) == ADDR_EXPR)
2853 fns = TREE_OPERAND (expr, 0);
2857 fn = instantiate_type (type_pointed_to, fns, 0);
2859 if (fn == error_mark_node)
2860 return error_mark_node;
2862 if (!TREE_PUBLIC (fn))
2864 if (really_overloaded_fn (fns))
2865 return error_mark_node;
2870 expr = build_unary_op (ADDR_EXPR, fn, 0);
2872 my_friendly_assert (same_type_p (type, TREE_TYPE (expr)),
2878 /* For a non-type template-parameter of type pointer to
2879 object, qualification conversions (_conv.qual_) and the
2880 array-to-pointer conversion (_conv.array_) are applied.
2881 [Note: In particular, neither the null pointer conversion
2882 (_conv.ptr_) nor the derived-to-base conversion
2883 (_conv.ptr_) are applied. Although 0 is a valid
2884 template-argument for a non-type template-parameter of
2885 integral type, it is not a valid template-argument for a
2886 non-type template-parameter of pointer type.]
2888 The call to decay_conversion performs the
2889 array-to-pointer conversion, if appropriate. */
2890 expr = decay_conversion (expr);
2892 if (expr == error_mark_node)
2893 return error_mark_node;
2895 return perform_qualification_conversions (type, expr);
2900 case REFERENCE_TYPE:
2902 tree type_referred_to = TREE_TYPE (type);
2904 if (TREE_CODE (type_referred_to) == FUNCTION_TYPE)
2906 /* For a non-type template-parameter of type reference to
2907 function, no conversions apply. If the
2908 template-argument represents a set of overloaded
2909 functions, the matching function is selected from the
2910 set (_over.over_). */
2914 fn = instantiate_type (type_referred_to, fns, 0);
2916 if (fn == error_mark_node)
2917 return error_mark_node;
2919 if (!TREE_PUBLIC (fn))
2921 if (really_overloaded_fn (fns))
2922 /* Don't issue an error here; we might get a different
2923 function if the overloading had worked out
2925 return error_mark_node;
2930 my_friendly_assert (same_type_p (type_referred_to,
2938 /* For a non-type template-parameter of type reference to
2939 object, no conversions apply. The type referred to by the
2940 reference may be more cv-qualified than the (otherwise
2941 identical) type of the template-argument. The
2942 template-parameter is bound directly to the
2943 template-argument, which must be an lvalue. */
2944 if ((TYPE_MAIN_VARIANT (expr_type)
2945 != TYPE_MAIN_VARIANT (type_referred_to))
2946 || !at_least_as_qualified_p (type_referred_to,
2948 || !real_lvalue_p (expr))
2949 return error_mark_node;
2958 if (!TYPE_PTRMEMFUNC_P (type))
2959 /* This handles templates like
2960 template<class T, T t> void f();
2961 when T is substituted with any class. The second template
2962 parameter becomes invalid and the template candidate is
2964 return error_mark_node;
2966 /* For a non-type template-parameter of type pointer to member
2967 function, no conversions apply. If the template-argument
2968 represents a set of overloaded member functions, the
2969 matching member function is selected from the set
2972 if (!TYPE_PTRMEMFUNC_P (expr_type) &&
2973 expr_type != unknown_type_node)
2974 return error_mark_node;
2976 if (TREE_CODE (expr) == PTRMEM_CST)
2978 /* A ptr-to-member constant. */
2979 if (!same_type_p (type, expr_type))
2980 return error_mark_node;
2985 if (TREE_CODE (expr) != ADDR_EXPR)
2986 return error_mark_node;
2988 expr = instantiate_type (type, expr, 0);
2990 if (expr == error_mark_node)
2991 return error_mark_node;
2993 my_friendly_assert (same_type_p (type, TREE_TYPE (expr)),
3000 /* All non-type parameters must have one of these types. */
3001 my_friendly_abort (0);
3005 return error_mark_node;
3008 /* Return 1 if PARM_PARMS and ARG_PARMS matches using rule for
3009 template template parameters. Both PARM_PARMS and ARG_PARMS are
3010 vectors of TREE_LIST nodes containing TYPE_DECL, TEMPLATE_DECL
3013 ARG_PARMS may contain more parameters than PARM_PARMS. If this is
3014 the case, then extra parameters must have default arguments.
3016 Consider the example:
3017 template <class T, class Allocator = allocator> class vector;
3018 template<template <class U> class TT> class C;
3020 C<vector> is a valid instantiation. PARM_PARMS for the above code
3021 contains a TYPE_DECL (for U), ARG_PARMS contains two TYPE_DECLs (for
3022 T and Allocator) and OUTER_ARGS contains the argument that is used to
3023 substitute the TT parameter. */
3026 coerce_template_template_parms (parm_parms, arg_parms, complain,
3027 in_decl, outer_args)
3028 tree parm_parms, arg_parms;
3030 tree in_decl, outer_args;
3032 int nparms, nargs, i;
3035 my_friendly_assert (TREE_CODE (parm_parms) == TREE_VEC, 0);
3036 my_friendly_assert (TREE_CODE (arg_parms) == TREE_VEC, 0);
3038 nparms = TREE_VEC_LENGTH (parm_parms);
3039 nargs = TREE_VEC_LENGTH (arg_parms);
3041 /* The rule here is opposite of coerce_template_parms. */
3044 && TREE_PURPOSE (TREE_VEC_ELT (arg_parms, nparms)) == NULL_TREE))
3047 for (i = 0; i < nparms; ++i)
3049 parm = TREE_VALUE (TREE_VEC_ELT (parm_parms, i));
3050 arg = TREE_VALUE (TREE_VEC_ELT (arg_parms, i));
3052 if (arg == NULL_TREE || arg == error_mark_node
3053 || parm == NULL_TREE || parm == error_mark_node)
3056 if (TREE_CODE (arg) != TREE_CODE (parm))
3059 switch (TREE_CODE (parm))
3065 /* We encounter instantiations of templates like
3066 template <template <template <class> class> class TT>
3069 tree parmparm = DECL_INNERMOST_TEMPLATE_PARMS (parm);
3070 tree argparm = DECL_INNERMOST_TEMPLATE_PARMS (arg);
3072 if (!coerce_template_template_parms (parmparm, argparm,
3080 /* The tsubst call is used to handle cases such as
3081 template <class T, template <T> class TT> class D;
3082 i.e. the parameter list of TT depends on earlier parameters. */
3083 if (!same_type_p (tsubst (TREE_TYPE (parm), outer_args,
3090 my_friendly_abort (0);
3096 /* Convert the indicated template ARG as necessary to match the
3097 indicated template PARM. Returns the converted ARG, or
3098 error_mark_node if the conversion was unsuccessful. Error messages
3099 are issued if COMPLAIN is non-zero. This conversion is for the Ith
3100 parameter in the parameter list. ARGS is the full set of template
3101 arguments deduced so far. */
3104 convert_template_argument (parm, arg, args, complain, i, in_decl)
3114 int is_type, requires_type, is_tmpl_type, requires_tmpl_type;
3116 inner_args = innermost_args (args);
3118 if (TREE_CODE (arg) == TREE_LIST
3119 && TREE_TYPE (arg) != NULL_TREE
3120 && TREE_CODE (TREE_TYPE (arg)) == OFFSET_TYPE)
3122 /* The template argument was the name of some
3123 member function. That's usually
3124 illegal, but static members are OK. In any
3125 case, grab the underlying fields/functions
3126 and issue an error later if required. */
3127 arg = TREE_VALUE (arg);
3128 TREE_TYPE (arg) = unknown_type_node;
3131 requires_tmpl_type = TREE_CODE (parm) == TEMPLATE_DECL;
3132 requires_type = (TREE_CODE (parm) == TYPE_DECL
3133 || requires_tmpl_type);
3135 /* Check if it is a class template. If REQUIRES_TMPL_TYPE is true,
3136 we also accept implicitly created TYPE_DECL as a valid argument.
3137 This is necessary to handle the case where we pass a template name
3138 to a template template parameter in a scope where we've derived from
3139 in instantiation of that template, so the template name refers to that
3140 instantiation. We really ought to handle this better. */
3142 = ((TREE_CODE (arg) == TEMPLATE_DECL
3143 && TREE_CODE (DECL_TEMPLATE_RESULT (arg)) == TYPE_DECL)
3144 || (TREE_CODE (arg) == TEMPLATE_TEMPLATE_PARM
3145 && !TEMPLATE_TEMPLATE_PARM_TEMPLATE_INFO (arg))
3146 || (TREE_CODE (arg) == RECORD_TYPE
3147 && CLASSTYPE_TEMPLATE_INFO (arg)
3148 && TREE_CODE (TYPE_NAME (arg)) == TYPE_DECL
3149 && DECL_ARTIFICIAL (TYPE_NAME (arg))
3150 && requires_tmpl_type
3151 && is_base_of_enclosing_class (arg, current_class_type)));
3152 if (is_tmpl_type && TREE_CODE (arg) == TEMPLATE_TEMPLATE_PARM)
3153 arg = TYPE_STUB_DECL (arg);
3154 else if (is_tmpl_type && TREE_CODE (arg) == RECORD_TYPE)
3155 arg = CLASSTYPE_TI_TEMPLATE (arg);
3157 is_type = TREE_CODE_CLASS (TREE_CODE (arg)) == 't' || is_tmpl_type;
3159 if (requires_type && ! is_type && TREE_CODE (arg) == SCOPE_REF
3160 && TREE_CODE (TREE_OPERAND (arg, 0)) == TEMPLATE_TYPE_PARM)
3162 cp_pedwarn ("to refer to a type member of a template parameter,");
3163 cp_pedwarn (" use `typename %E'", arg);
3165 arg = make_typename_type (TREE_OPERAND (arg, 0),
3166 TREE_OPERAND (arg, 1),
3170 if (is_type != requires_type)
3176 cp_error ("type/value mismatch at argument %d in template parameter list for `%D'",
3179 cp_error (" expected a constant of type `%T', got `%T'",
3181 (is_tmpl_type ? DECL_NAME (arg) : arg));
3183 cp_error (" expected a type, got `%E'", arg);
3186 return error_mark_node;
3188 if (is_tmpl_type ^ requires_tmpl_type)
3190 if (in_decl && complain)
3192 cp_error ("type/value mismatch at argument %d in template parameter list for `%D'",
3195 cp_error (" expected a type, got `%T'", DECL_NAME (arg));
3197 cp_error (" expected a class template, got `%T'", arg);
3199 return error_mark_node;
3204 if (requires_tmpl_type)
3206 tree parmparm = DECL_INNERMOST_TEMPLATE_PARMS (parm);
3207 tree argparm = DECL_INNERMOST_TEMPLATE_PARMS (arg);
3209 if (coerce_template_template_parms (parmparm, argparm, complain,
3210 in_decl, inner_args))
3214 /* TEMPLATE_TEMPLATE_PARM node is preferred over
3216 if (val != error_mark_node
3217 && DECL_TEMPLATE_TEMPLATE_PARM_P (val))
3218 val = TREE_TYPE (val);
3222 if (in_decl && complain)
3224 cp_error ("type/value mismatch at argument %d in template parameter list for `%D'",
3226 cp_error (" expected a template of type `%D', got `%D'", parm, arg);
3229 val = error_mark_node;
3234 val = groktypename (arg);
3235 if (! processing_template_decl)
3237 /* [basic.link]: A name with no linkage (notably, the
3238 name of a class or enumeration declared in a local
3239 scope) shall not be used to declare an entity with
3240 linkage. This implies that names with no linkage
3241 cannot be used as template arguments. */
3242 tree t = no_linkage_check (val);
3245 if (ANON_AGGRNAME_P (TYPE_IDENTIFIER (t)))
3247 ("template-argument `%T' uses anonymous type", val);
3250 ("template-argument `%T' uses local type `%T'",
3252 return error_mark_node;
3259 tree t = tsubst (TREE_TYPE (parm), args, complain, in_decl);
3261 if (processing_template_decl)
3262 arg = maybe_fold_nontype_arg (arg);
3264 if (!uses_template_parms (arg) && !uses_template_parms (t))
3265 /* We used to call digest_init here. However, digest_init
3266 will report errors, which we don't want when complain
3267 is zero. More importantly, digest_init will try too
3268 hard to convert things: for example, `0' should not be
3269 converted to pointer type at this point according to
3270 the standard. Accepting this is not merely an
3271 extension, since deciding whether or not these
3272 conversions can occur is part of determining which
3273 function template to call, or whether a given epxlicit
3274 argument specification is legal. */
3275 val = convert_nontype_argument (t, arg);
3279 if (val == NULL_TREE)
3280 val = error_mark_node;
3281 else if (val == error_mark_node && complain)
3282 cp_error ("could not convert template argument `%E' to `%T'",
3289 /* Convert all template arguments to their appropriate types, and
3290 return a vector containing the innermost resulting template
3291 arguments. If any error occurs, return error_mark_node, and, if
3292 COMPLAIN is non-zero, issue an error message. Some error messages
3293 are issued even if COMPLAIN is zero; for instance, if a template
3294 argument is composed from a local class.
3296 If REQUIRE_ALL_ARGUMENTS is non-zero, all arguments must be
3297 provided in ARGLIST, or else trailing parameters must have default
3298 values. If REQUIRE_ALL_ARGUMENTS is zero, we will attempt argument
3299 deduction for any unspecified trailing arguments.
3301 The resulting TREE_VEC is allocated on a temporary obstack, and
3302 must be explicitly copied if it will be permanent. */
3305 coerce_template_parms (parms, args, in_decl,
3307 require_all_arguments)
3311 int require_all_arguments;
3313 int nparms, nargs, i, lost = 0;
3316 tree new_inner_args;
3318 inner_args = innermost_args (args);
3319 nargs = NUM_TMPL_ARGS (inner_args);
3320 nparms = TREE_VEC_LENGTH (parms);
3324 && require_all_arguments
3325 && TREE_PURPOSE (TREE_VEC_ELT (parms, nargs)) == NULL_TREE))
3329 cp_error ("wrong number of template arguments (%d, should be %d)",
3333 cp_error_at ("provided for `%D'", in_decl);
3336 return error_mark_node;
3339 new_inner_args = make_tree_vec (nparms);
3340 new_args = add_outermost_template_args (args, new_inner_args);
3341 for (i = 0; i < nparms; i++)
3346 /* Get the Ith template parameter. */
3347 parm = TREE_VEC_ELT (parms, i);
3349 /* Calculate the Ith argument. */
3350 if (inner_args && TREE_CODE (inner_args) == TREE_LIST)
3352 arg = TREE_VALUE (inner_args);
3353 inner_args = TREE_CHAIN (inner_args);
3356 arg = TREE_VEC_ELT (inner_args, i);
3357 /* If no template argument was supplied, look for a default
3359 else if (TREE_PURPOSE (parm) == NULL_TREE)
3361 /* There was no default value. */
3362 my_friendly_assert (!require_all_arguments, 0);
3365 else if (TREE_CODE (TREE_VALUE (parm)) == TYPE_DECL)
3366 arg = tsubst (TREE_PURPOSE (parm), new_args, complain, in_decl);
3368 arg = tsubst_expr (TREE_PURPOSE (parm), new_args, complain,
3371 /* Now, convert the Ith argument, as necessary. */
3372 if (arg == NULL_TREE)
3373 /* We're out of arguments. */
3375 my_friendly_assert (!require_all_arguments, 0);
3378 else if (arg == error_mark_node)
3380 cp_error ("template argument %d is invalid", i + 1);
3381 arg = error_mark_node;
3384 arg = convert_template_argument (TREE_VALUE (parm),
3385 arg, new_args, complain, i,
3388 if (arg == error_mark_node)
3390 TREE_VEC_ELT (new_inner_args, i) = arg;
3394 return error_mark_node;
3396 return new_inner_args;
3399 /* Returns 1 if template args OT and NT are equivalent. */
3402 template_args_equal (ot, nt)
3407 if (TREE_CODE (nt) != TREE_CODE (ot))
3409 if (TREE_CODE (nt) == TREE_VEC)
3410 /* For member templates */
3411 return comp_template_args (ot, nt);
3412 else if (TREE_CODE_CLASS (TREE_CODE (ot)) == 't')
3413 return same_type_p (ot, nt);
3415 return (cp_tree_equal (ot, nt) > 0);
3418 /* Returns 1 iff the OLDARGS and NEWARGS are in fact identical sets
3419 of template arguments. Returns 0 otherwise. */
3422 comp_template_args (oldargs, newargs)
3423 tree oldargs, newargs;
3427 if (TREE_VEC_LENGTH (oldargs) != TREE_VEC_LENGTH (newargs))
3430 for (i = 0; i < TREE_VEC_LENGTH (oldargs); ++i)
3432 tree nt = TREE_VEC_ELT (newargs, i);
3433 tree ot = TREE_VEC_ELT (oldargs, i);
3435 if (! template_args_equal (ot, nt))
3441 /* Given class template name and parameter list, produce a user-friendly name
3442 for the instantiation. */
3445 mangle_class_name_for_template (name, parms, arglist)
3447 tree parms, arglist;
3449 static struct obstack scratch_obstack;
3450 static char *scratch_firstobj;
3453 if (!scratch_firstobj)
3454 gcc_obstack_init (&scratch_obstack);
3456 obstack_free (&scratch_obstack, scratch_firstobj);
3457 scratch_firstobj = obstack_alloc (&scratch_obstack, 1);
3459 #define ccat(c) obstack_1grow (&scratch_obstack, (c));
3460 #define cat(s) obstack_grow (&scratch_obstack, (s), strlen (s))
3464 nparms = TREE_VEC_LENGTH (parms);
3465 arglist = innermost_args (arglist);
3466 my_friendly_assert (nparms == TREE_VEC_LENGTH (arglist), 268);
3467 for (i = 0; i < nparms; i++)
3469 tree parm = TREE_VALUE (TREE_VEC_ELT (parms, i));
3470 tree arg = TREE_VEC_ELT (arglist, i);
3475 if (TREE_CODE (parm) == TYPE_DECL)
3477 cat (type_as_string (arg, TS_CHASE_TYPEDEFS));
3480 else if (TREE_CODE (parm) == TEMPLATE_DECL)
3482 if (TREE_CODE (arg) == TEMPLATE_DECL)
3484 /* Already substituted with real template. Just output
3485 the template name here */
3486 tree context = DECL_CONTEXT (arg);
3489 /* The template may be defined in a namespace, or
3490 may be a member template. */
3491 my_friendly_assert (TREE_CODE (context) == NAMESPACE_DECL
3492 || CLASS_TYPE_P (context),
3494 cat(decl_as_string (DECL_CONTEXT (arg), 0));
3497 cat (IDENTIFIER_POINTER (DECL_NAME (arg)));
3500 /* Output the parameter declaration */
3501 cat (type_as_string (arg, TS_CHASE_TYPEDEFS));
3505 my_friendly_assert (TREE_CODE (parm) == PARM_DECL, 269);
3507 if (TREE_CODE (arg) == TREE_LIST)
3509 /* New list cell was built because old chain link was in
3511 my_friendly_assert (TREE_PURPOSE (arg) == NULL_TREE, 270);
3512 arg = TREE_VALUE (arg);
3514 /* No need to check arglist against parmlist here; we did that
3515 in coerce_template_parms, called from lookup_template_class. */
3516 cat (expr_as_string (arg, 0));
3519 char *bufp = obstack_next_free (&scratch_obstack);
3521 while (bufp[offset - 1] == ' ')
3523 obstack_blank_fast (&scratch_obstack, offset);
3525 /* B<C<char> >, not B<C<char>> */
3526 if (bufp[offset - 1] == '>')
3531 return (char *) obstack_base (&scratch_obstack);
3535 classtype_mangled_name (t)
3538 if (CLASSTYPE_TEMPLATE_INFO (t)
3539 /* Specializations have already had their names set up in
3540 lookup_template_class. */
3541 && !CLASSTYPE_TEMPLATE_SPECIALIZATION (t))
3543 tree tmpl = most_general_template (CLASSTYPE_TI_TEMPLATE (t));
3545 /* For non-primary templates, the template parameters are
3546 implicit from their surrounding context. */
3547 if (PRIMARY_TEMPLATE_P (tmpl))
3549 tree name = DECL_NAME (tmpl);
3550 char *mangled_name = mangle_class_name_for_template
3551 (IDENTIFIER_POINTER (name),
3552 DECL_INNERMOST_TEMPLATE_PARMS (tmpl),
3553 CLASSTYPE_TI_ARGS (t));
3554 tree id = get_identifier (mangled_name);
3555 IDENTIFIER_TEMPLATE (id) = name;
3560 return TYPE_IDENTIFIER (t);
3564 add_pending_template (d)
3569 if (TREE_CODE_CLASS (TREE_CODE (d)) == 't')
3570 ti = CLASSTYPE_TEMPLATE_INFO (d);
3572 ti = DECL_TEMPLATE_INFO (d);
3574 if (TI_PENDING_TEMPLATE_FLAG (ti))
3577 *template_tail = tree_cons (build_srcloc_here (), d, NULL_TREE);
3578 template_tail = &TREE_CHAIN (*template_tail);
3579 TI_PENDING_TEMPLATE_FLAG (ti) = 1;
3583 /* Return a TEMPLATE_ID_EXPR corresponding to the indicated FNS (which
3584 may be either a _DECL or an overloaded function or an
3585 IDENTIFIER_NODE), and ARGLIST. */
3588 lookup_template_function (fns, arglist)
3593 if (fns == NULL_TREE)
3595 cp_error ("non-template used as template");
3596 return error_mark_node;
3599 type = TREE_TYPE (fns);
3600 if (TREE_CODE (fns) == OVERLOAD || !type)
3601 type = unknown_type_node;
3603 if (processing_template_decl)
3604 return build_min (TEMPLATE_ID_EXPR, type, fns, arglist);
3606 return build (TEMPLATE_ID_EXPR, type, fns, arglist);
3609 /* Within the scope of a template class S<T>, the name S gets bound
3610 (in build_self_reference) to a TYPE_DECL for the class, not a
3611 TEMPLATE_DECL. If DECL is a TYPE_DECL for current_class_type,
3612 or one of its enclosing classes, and that type is a template,
3613 return the associated TEMPLATE_DECL. Otherwise, the original
3614 DECL is returned. */
3617 maybe_get_template_decl_from_type_decl (decl)
3620 return (decl != NULL_TREE
3621 && TREE_CODE (decl) == TYPE_DECL
3622 && DECL_ARTIFICIAL (decl)
3623 && CLASS_TYPE_P (TREE_TYPE (decl))
3624 && CLASSTYPE_TEMPLATE_INFO (TREE_TYPE (decl)))
3625 ? CLASSTYPE_TI_TEMPLATE (TREE_TYPE (decl)) : decl;
3628 /* Given an IDENTIFIER_NODE (type TEMPLATE_DECL) and a chain of
3629 parameters, find the desired type.
3631 D1 is the PTYPENAME terminal, and ARGLIST is the list of arguments.
3632 (Actually ARGLIST may be either a TREE_LIST or a TREE_VEC. It will
3633 be a TREE_LIST if called directly from the parser, and a TREE_VEC
3634 otherwise.) Since ARGLIST is build on the temp_decl_obstack, we must
3635 copy it here to keep it from being reclaimed when the decl storage
3638 IN_DECL, if non-NULL, is the template declaration we are trying to
3641 If ENTERING_SCOPE is non-zero, we are about to enter the scope of
3642 the class we are looking up.
3644 If the template class is really a local class in a template
3645 function, then the FUNCTION_CONTEXT is the function in which it is
3646 being instantiated. */
3649 lookup_template_class (d1, arglist, in_decl, context, entering_scope)
3655 tree template = NULL_TREE, parmlist;
3658 if (TREE_CODE (d1) == IDENTIFIER_NODE)
3660 if (IDENTIFIER_VALUE (d1)
3661 && DECL_TEMPLATE_TEMPLATE_PARM_P (IDENTIFIER_VALUE (d1)))
3662 template = IDENTIFIER_VALUE (d1);
3666 push_decl_namespace (context);
3667 template = lookup_name (d1, /*prefer_type=*/0);
3668 template = maybe_get_template_decl_from_type_decl (template);
3670 pop_decl_namespace ();
3673 context = DECL_CONTEXT (template);
3675 else if (TREE_CODE (d1) == TYPE_DECL && IS_AGGR_TYPE (TREE_TYPE (d1)))
3677 tree type = TREE_TYPE (d1);
3679 /* If we are declaring a constructor, say A<T>::A<T>, we will get
3680 an implicit typename for the second A. Deal with it. */
3681 if (TREE_CODE (type) == TYPENAME_TYPE && TREE_TYPE (type))
3682 type = TREE_TYPE (type);
3684 if (CLASSTYPE_TEMPLATE_INFO (type))
3686 template = CLASSTYPE_TI_TEMPLATE (type);
3687 d1 = DECL_NAME (template);
3690 else if (TREE_CODE (d1) == ENUMERAL_TYPE
3691 || (TREE_CODE_CLASS (TREE_CODE (d1)) == 't'
3692 && IS_AGGR_TYPE (d1)))
3694 template = TYPE_TI_TEMPLATE (d1);
3695 d1 = DECL_NAME (template);
3697 else if (TREE_CODE (d1) == TEMPLATE_DECL
3698 && TREE_CODE (DECL_RESULT (d1)) == TYPE_DECL)
3701 d1 = DECL_NAME (template);
3702 context = DECL_CONTEXT (template);
3705 my_friendly_abort (272);
3707 /* With something like `template <class T> class X class X { ... };'
3708 we could end up with D1 having nothing but an IDENTIFIER_VALUE.
3709 We don't want to do that, but we have to deal with the situation,
3710 so let's give them some syntax errors to chew on instead of a
3714 cp_error ("`%T' is not a template", d1);
3715 return error_mark_node;
3718 if (context == NULL_TREE)
3719 context = global_namespace;
3721 if (TREE_CODE (template) != TEMPLATE_DECL)
3723 cp_error ("non-template type `%T' used as a template", d1);
3725 cp_error_at ("for template declaration `%D'", in_decl);
3726 return error_mark_node;
3729 if (DECL_TEMPLATE_TEMPLATE_PARM_P (template))
3731 /* Create a new TEMPLATE_DECL and TEMPLATE_TEMPLATE_PARM node to store
3732 template arguments */
3734 tree parm = copy_template_template_parm (TREE_TYPE (template));
3735 tree template2 = TYPE_STUB_DECL (parm);
3738 parmlist = DECL_INNERMOST_TEMPLATE_PARMS (template);
3740 arglist2 = coerce_template_parms (parmlist, arglist, template, 1, 1);
3741 if (arglist2 == error_mark_node)
3742 return error_mark_node;
3744 TEMPLATE_TEMPLATE_PARM_TEMPLATE_INFO (parm)
3745 = tree_cons (template2, arglist2, NULL_TREE);
3746 TYPE_SIZE (parm) = 0;
3751 tree template_type = TREE_TYPE (template);
3754 tree found = NULL_TREE;
3757 int is_partial_instantiation;
3759 gen_tmpl = most_general_template (template);
3760 parmlist = DECL_TEMPLATE_PARMS (gen_tmpl);
3761 parm_depth = TMPL_PARMS_DEPTH (parmlist);
3762 arg_depth = TMPL_ARGS_DEPTH (arglist);
3764 if (arg_depth == 1 && parm_depth > 1)
3766 /* We've been given an incomplete set of template arguments.
3769 template <class T> struct S1 {
3770 template <class U> struct S2 {};
3771 template <class U> struct S2<U*> {};
3774 we will be called with an ARGLIST of `U*', but the
3775 TEMPLATE will be `template <class T> template
3776 <class U> struct S1<T>::S2'. We must fill in the missing
3779 = add_outermost_template_args (TYPE_TI_ARGS (TREE_TYPE (template)),
3781 arg_depth = TMPL_ARGS_DEPTH (arglist);
3784 /* Now we should enough arguments. */
3785 my_friendly_assert (parm_depth == arg_depth, 0);
3787 /* From here on, we're only interested in the most general
3789 template = gen_tmpl;
3791 /* Calculate the BOUND_ARGS. These will be the args that are
3792 actually tsubst'd into the definition to create the
3796 /* We have multiple levels of arguments to coerce, at once. */
3798 int saved_depth = TMPL_ARGS_DEPTH (arglist);
3800 tree bound_args = make_tree_vec (parm_depth);
3802 for (i = saved_depth,
3803 t = DECL_TEMPLATE_PARMS (template);
3804 i > 0 && t != NULL_TREE;
3805 --i, t = TREE_CHAIN (t))
3807 tree a = coerce_template_parms (TREE_VALUE (t),
3808 arglist, template, 1, 1);
3809 SET_TMPL_ARGS_LEVEL (bound_args, i, a);
3811 /* We temporarily reduce the length of the ARGLIST so
3812 that coerce_template_parms will see only the arguments
3813 corresponding to the template parameters it is
3815 TREE_VEC_LENGTH (arglist)--;
3818 /* Restore the ARGLIST to its full size. */
3819 TREE_VEC_LENGTH (arglist) = saved_depth;
3821 arglist = bound_args;
3825 = coerce_template_parms (INNERMOST_TEMPLATE_PARMS (parmlist),
3826 innermost_args (arglist),
3829 if (arglist == error_mark_node)
3830 /* We were unable to bind the arguments. */
3831 return error_mark_node;
3833 /* In the scope of a template class, explicit references to the
3834 template class refer to the type of the template, not any
3835 instantiation of it. For example, in:
3837 template <class T> class C { void f(C<T>); }
3839 the `C<T>' is just the same as `C'. Outside of the
3840 class, however, such a reference is an instantiation. */
3841 if (comp_template_args (TYPE_TI_ARGS (template_type),
3844 found = template_type;
3846 if (!entering_scope && PRIMARY_TEMPLATE_P (template))
3850 /* Note that we use DECL_CONTEXT, rather than
3851 CP_DECL_CONTEXT, so that the termination test is
3852 always just `ctx'. We're not interested in namepace
3854 for (ctx = current_class_type;
3856 ctx = (TREE_CODE_CLASS (TREE_CODE (ctx)) == 't')
3857 ? TYPE_CONTEXT (ctx) : DECL_CONTEXT (ctx))
3858 if (same_type_p (ctx, template_type))
3862 /* We're not in the scope of the class, so the
3863 TEMPLATE_TYPE is not the type we want after
3871 for (found = DECL_TEMPLATE_INSTANTIATIONS (template);
3872 found; found = TREE_CHAIN (found))
3873 if (comp_template_args (TREE_PURPOSE (found), arglist))
3877 found = TREE_VALUE (found);
3883 /* This type is a "partial instantiation" if any of the template
3884 arguments still inolve template parameters. Note that we set
3885 IS_PARTIAL_INSTANTIATION for partial specializations as
3887 is_partial_instantiation = uses_template_parms (arglist);
3889 if (!is_partial_instantiation
3890 && !PRIMARY_TEMPLATE_P (template)
3891 && TREE_CODE (CP_DECL_CONTEXT (template)) == NAMESPACE_DECL)
3893 found = xref_tag_from_type (TREE_TYPE (template),
3894 DECL_NAME (template),
3899 /* Create the type. */
3900 if (TREE_CODE (template_type) == ENUMERAL_TYPE)
3902 if (!is_partial_instantiation)
3903 t = start_enum (TYPE_IDENTIFIER (template_type));
3905 /* We don't want to call start_enum for this type, since
3906 the values for the enumeration constants may involve
3907 template parameters. And, no one should be interested
3908 in the enumeration constants for such a type. */
3909 t = make_node (ENUMERAL_TYPE);
3913 t = make_aggr_type (TREE_CODE (template_type));
3914 CLASSTYPE_DECLARED_CLASS (t)
3915 = CLASSTYPE_DECLARED_CLASS (template_type);
3916 CLASSTYPE_GOT_SEMICOLON (t) = 1;
3917 SET_CLASSTYPE_IMPLICIT_INSTANTIATION (t);
3918 TYPE_FOR_JAVA (t) = TYPE_FOR_JAVA (template_type);
3920 /* A local class. Make sure the decl gets registered properly. */
3921 if (context == current_function_decl)
3922 pushtag (DECL_NAME (template), t, 0);
3925 /* If we called start_enum or pushtag above, this information
3926 will already be set up. */
3929 TYPE_CONTEXT (t) = FROB_CONTEXT (context);
3931 type_decl = create_implicit_typedef (DECL_NAME (template), t);
3932 DECL_CONTEXT (type_decl) = TYPE_CONTEXT (t);
3933 TYPE_STUB_DECL (t) = type_decl;
3934 DECL_SOURCE_FILE (type_decl)
3935 = DECL_SOURCE_FILE (TYPE_STUB_DECL (template_type));
3936 DECL_SOURCE_LINE (type_decl)
3937 = DECL_SOURCE_LINE (TYPE_STUB_DECL (template_type));
3940 type_decl = TYPE_NAME (t);
3942 /* Set up the template information. We have to figure out which
3943 template is the immediate parent if this is a full
3945 if (parm_depth == 1 || is_partial_instantiation
3946 || !PRIMARY_TEMPLATE_P (template))
3947 /* This case is easy; there are no member templates involved. */
3951 /* This is a full instantiation of a member template. There
3952 should be some partial instantiation of which this is an
3955 for (found = DECL_TEMPLATE_INSTANTIATIONS (template);
3956 found; found = TREE_CHAIN (found))
3959 tree tmpl = CLASSTYPE_TI_TEMPLATE (TREE_VALUE (found));
3961 /* We only want partial instantiations, here, not
3962 specializations or full instantiations. */
3963 if (CLASSTYPE_TEMPLATE_SPECIALIZATION (TREE_VALUE (found))
3964 || !uses_template_parms (TREE_VALUE (found)))
3967 /* Temporarily reduce by one the number of levels in the
3968 ARGLIST and in FOUND so as to avoid comparing the
3969 last set of arguments. */
3970 TREE_VEC_LENGTH (arglist)--;
3971 TREE_VEC_LENGTH (TREE_PURPOSE (found)) --;
3973 /* See if the arguments match. If they do, then TMPL is
3974 the partial instantiation we want. */
3975 success = comp_template_args (TREE_PURPOSE (found), arglist);
3977 /* Restore the argument vectors to their full size. */
3978 TREE_VEC_LENGTH (arglist)++;
3979 TREE_VEC_LENGTH (TREE_PURPOSE (found))++;
3989 my_friendly_abort (0);
3992 SET_TYPE_TEMPLATE_INFO (t,
3993 tree_cons (found, arglist, NULL_TREE));
3994 DECL_TEMPLATE_INSTANTIATIONS (template)
3995 = tree_cons (arglist, t,
3996 DECL_TEMPLATE_INSTANTIATIONS (template));
3998 if (TREE_CODE (t) == ENUMERAL_TYPE
3999 && !is_partial_instantiation)
4000 /* Now that the type has been registered on the instantiations
4001 list, we set up the enumerators. Because the enumeration
4002 constants may involve the enumeration type itself, we make
4003 sure to register the type first, and then create the
4004 constants. That way, doing tsubst_expr for the enumeration
4005 constants won't result in recursive calls here; we'll find
4006 the instantiation and exit above. */
4007 tsubst_enum (template_type, t, arglist);
4009 /* Reset the name of the type, now that CLASSTYPE_TEMPLATE_INFO
4011 if (TREE_CODE (t) != ENUMERAL_TYPE)
4012 DECL_NAME (type_decl) = classtype_mangled_name (t);
4013 DECL_ASSEMBLER_NAME (type_decl) = DECL_NAME (type_decl);
4014 if (!is_partial_instantiation)
4016 DECL_ASSEMBLER_NAME (type_decl)
4017 = get_identifier (build_overload_name (t, 1, 1));
4019 /* For backwards compatibility; code that uses
4020 -fexternal-templates expects looking up a template to
4021 instantiate it. I think DDD still relies on this.
4022 (jason 8/20/1998) */
4023 if (TREE_CODE (t) != ENUMERAL_TYPE
4024 && flag_external_templates
4025 && CLASSTYPE_INTERFACE_KNOWN (TREE_TYPE (template))
4026 && ! CLASSTYPE_INTERFACE_ONLY (TREE_TYPE (template)))
4027 add_pending_template (t);
4030 /* If the type makes use of template parameters, the
4031 code that generates debugging information will crash. */
4032 DECL_IGNORED_P (TYPE_STUB_DECL (t)) = 1;
4044 /* Called from for_each_template_parm via walk_tree. */
4047 for_each_template_parm_r (tp, walk_subtrees, d)
4053 struct pair_fn_data *pfd = (struct pair_fn_data *) d;
4054 tree_fn_t fn = pfd->fn;
4055 void *data = pfd->data;
4057 if (TREE_CODE_CLASS (TREE_CODE (t)) == 't'
4058 && for_each_template_parm (TYPE_CONTEXT (t), fn, data))
4059 return error_mark_node;
4061 switch (TREE_CODE (t))
4064 if (TYPE_PTRMEMFUNC_FLAG (t))
4070 if (!TYPE_TEMPLATE_INFO (t))
4072 else if (for_each_template_parm (TREE_VALUE (TYPE_TEMPLATE_INFO (t)),
4074 return error_mark_node;
4078 /* Since we're not going to walk subtrees, we have to do this
4080 if (for_each_template_parm (TYPE_METHOD_BASETYPE (t), fn, data))
4081 return error_mark_node;
4084 /* Check the return type. */
4085 if (for_each_template_parm (TREE_TYPE (t), fn, data))
4086 return error_mark_node;
4088 /* Check the parameter types. Since default arguments are not
4089 instantiated until they are needed, the TYPE_ARG_TYPES may
4090 contain expressions that involve template parameters. But,
4091 no-one should be looking at them yet. And, once they're
4092 instantiated, they don't contain template parameters, so
4093 there's no point in looking at them then, either. */
4097 for (parm = TYPE_ARG_TYPES (t); parm; parm = TREE_CHAIN (parm))
4098 if (for_each_template_parm (TREE_VALUE (parm), fn, data))
4099 return error_mark_node;
4101 /* Since we've already handled the TYPE_ARG_TYPES, we don't
4102 want walk_tree walking into them itself. */
4109 if (DECL_LANG_SPECIFIC (t) && DECL_TEMPLATE_INFO (t)
4110 && for_each_template_parm (DECL_TI_ARGS (t), fn, data))
4111 return error_mark_node;
4116 if (DECL_CONTEXT (t)
4117 && for_each_template_parm (DECL_CONTEXT (t), fn, data))
4118 return error_mark_node;
4121 case TEMPLATE_TEMPLATE_PARM:
4122 /* Record template parameters such as `T' inside `TT<T>'. */
4123 if (TEMPLATE_TEMPLATE_PARM_TEMPLATE_INFO (t)
4124 && for_each_template_parm (TYPE_TI_ARGS (t), fn, data))
4125 return error_mark_node;
4128 case TEMPLATE_TYPE_PARM:
4129 case TEMPLATE_PARM_INDEX:
4130 if (fn && (*fn)(t, data))
4131 return error_mark_node;
4133 return error_mark_node;
4137 /* A template template parameter is encountered */
4138 if (DECL_TEMPLATE_TEMPLATE_PARM_P (t)
4139 && for_each_template_parm (TREE_TYPE (t), fn, data))
4140 return error_mark_node;
4142 /* Already substituted template template parameter */
4147 if (!fn || for_each_template_parm (TYPENAME_TYPE_FULLNAME (t), fn, data))
4148 return error_mark_node;
4152 if (TREE_TYPE (t) && TYPE_PTRMEMFUNC_P (TREE_TYPE (t))
4153 && for_each_template_parm (TYPE_PTRMEMFUNC_FN_TYPE
4154 (TREE_TYPE (t)), fn, data))
4155 return error_mark_node;
4160 /* If there's no type, then this thing must be some expression
4161 involving template parameters. */
4162 if (!fn && !TREE_TYPE (t))
4163 return error_mark_node;
4168 case REINTERPRET_CAST_EXPR:
4169 case CONST_CAST_EXPR:
4170 case STATIC_CAST_EXPR:
4171 case DYNAMIC_CAST_EXPR:
4176 case PSEUDO_DTOR_EXPR:
4178 return error_mark_node;
4185 /* We didn't find any template parameters we liked. */
4189 /* For each TEMPLATE_TYPE_PARM, TEMPLATE_TEMPLATE_PARM, or
4190 TEMPLATE_PARM_INDEX in T, call FN with the parameter and the DATA.
4191 If FN returns non-zero, the iteration is terminated, and
4192 for_each_template_parm returns 1. Otherwise, the iteration
4193 continues. If FN never returns a non-zero value, the value
4194 returned by for_each_template_parm is 0. If FN is NULL, it is
4195 considered to be the function which always returns 1. */
4198 for_each_template_parm (t, fn, data)
4203 struct pair_fn_data pfd;
4209 /* Walk the tree. */
4210 return walk_tree (&t, for_each_template_parm_r, &pfd) != NULL_TREE;
4214 uses_template_parms (t)
4217 return for_each_template_parm (t, 0, 0);
4220 static struct tinst_level *current_tinst_level;
4221 static struct tinst_level *free_tinst_level;
4222 static int tinst_depth;
4223 extern int max_tinst_depth;
4224 #ifdef GATHER_STATISTICS
4227 static int tinst_level_tick;
4228 static int last_template_error_tick;
4230 /* Print out all the template instantiations that we are currently
4231 working on. If ERR, we are being called from cp_thing, so do
4232 the right thing for an error message. */
4235 print_template_context (err)
4238 struct tinst_level *p = current_tinst_level;
4240 char *file = input_filename;
4244 if (current_function_decl != p->decl
4245 && current_function_decl != NULL_TREE)
4246 /* We can get here during the processing of some synthesized
4247 method. Then, p->decl will be the function that's causing
4252 if (current_function_decl == p->decl)
4253 /* Avoid redundancy with the the "In function" line. */;
4255 fprintf (stderr, "%s: In instantiation of `%s':\n",
4256 file, decl_as_string (p->decl, TS_DECL_TYPE | TS_FUNC_NORETURN));
4264 for (; p; p = p->next)
4266 fprintf (stderr, "%s:%d: instantiated from `%s'\n", file, line,
4267 decl_as_string (p->decl, TS_DECL_TYPE | TS_FUNC_NORETURN));
4271 fprintf (stderr, "%s:%d: instantiated from here\n", file, line);
4274 /* Called from cp_thing to print the template context for an error. */
4277 maybe_print_template_context ()
4279 if (last_template_error_tick == tinst_level_tick
4280 || current_tinst_level == 0)
4283 last_template_error_tick = tinst_level_tick;
4284 print_template_context (1);
4288 push_tinst_level (d)
4291 struct tinst_level *new;
4293 if (tinst_depth >= max_tinst_depth)
4295 /* If the instantiation in question still has unbound template parms,
4296 we don't really care if we can't instantiate it, so just return.
4297 This happens with base instantiation for implicit `typename'. */
4298 if (uses_template_parms (d))
4301 last_template_error_tick = tinst_level_tick;
4302 error ("template instantiation depth exceeds maximum of %d",
4304 error (" (use -ftemplate-depth-NN to increase the maximum)");
4305 cp_error (" instantiating `%D'", d);
4307 print_template_context (0);
4312 if (free_tinst_level)
4314 new = free_tinst_level;
4315 free_tinst_level = new->next;
4318 new = (struct tinst_level *) xmalloc (sizeof (struct tinst_level));
4322 new->file = input_filename;
4323 new->next = current_tinst_level;
4324 current_tinst_level = new;
4327 #ifdef GATHER_STATISTICS
4328 if (tinst_depth > depth_reached)
4329 depth_reached = tinst_depth;
4339 struct tinst_level *old = current_tinst_level;
4341 /* Restore the filename and line number stashed away when we started
4342 this instantiation. */
4344 input_filename = old->file;
4345 extract_interface_info ();
4347 current_tinst_level = old->next;
4348 old->next = free_tinst_level;
4349 free_tinst_level = old;
4354 struct tinst_level *
4357 struct tinst_level *p = current_tinst_level;
4360 for (; p->next ; p = p->next )
4365 /* DECL is a friend FUNCTION_DECL or TEMPLATE_DECL. ARGS is the
4366 vector of template arguments, as for tsubst.
4368 Returns an appropriate tsbust'd friend declaration. */
4371 tsubst_friend_function (decl, args)
4377 char *file = input_filename;
4379 lineno = DECL_SOURCE_LINE (decl);
4380 input_filename = DECL_SOURCE_FILE (decl);
4382 if (TREE_CODE (decl) == FUNCTION_DECL
4383 && DECL_TEMPLATE_INSTANTIATION (decl)
4384 && TREE_CODE (DECL_TI_TEMPLATE (decl)) != TEMPLATE_DECL)
4385 /* This was a friend declared with an explicit template
4386 argument list, e.g.:
4390 to indicate that f was a template instantiation, not a new
4391 function declaration. Now, we have to figure out what
4392 instantiation of what template. */
4399 = lookup_template_function (tsubst_expr (DECL_TI_TEMPLATE (decl),
4400 args, /*complain=*/1,
4402 tsubst (DECL_TI_ARGS (decl),
4403 args, /*complain=*/1,
4405 new_friend = tsubst (decl, args, /*complain=*/1, NULL_TREE);
4406 tmpl = determine_specialization (template_id, new_friend,
4408 /*need_member_template=*/0);
4409 new_friend = instantiate_template (tmpl, new_args);
4413 new_friend = tsubst (decl, args, /*complain=*/1, NULL_TREE);
4415 /* The NEW_FRIEND will look like an instantiation, to the
4416 compiler, but is not an instantiation from the point of view of
4417 the language. For example, we might have had:
4419 template <class T> struct S {
4420 template <class U> friend void f(T, U);
4423 Then, in S<int>, template <class U> void f(int, U) is not an
4424 instantiation of anything. */
4425 DECL_USE_TEMPLATE (new_friend) = 0;
4426 if (TREE_CODE (decl) == TEMPLATE_DECL)
4427 DECL_USE_TEMPLATE (DECL_TEMPLATE_RESULT (new_friend)) = 0;
4429 /* The mangled name for the NEW_FRIEND is incorrect. The call to
4430 tsubst will have resulted in a call to
4431 set_mangled_name_for_template_decl. But, the function is not a
4432 template instantiation and should not be mangled like one.
4433 Therefore, we remangle the function name. We don't have to do
4434 this if the NEW_FRIEND is a template since
4435 set_mangled_name_for_template_decl doesn't do anything if the
4436 function declaration still uses template arguments. */
4437 if (TREE_CODE (new_friend) != TEMPLATE_DECL)
4439 set_mangled_name_for_decl (new_friend);
4440 DECL_RTL (new_friend) = 0;
4441 make_decl_rtl (new_friend, NULL_PTR, 1);
4444 if (DECL_NAMESPACE_SCOPE_P (new_friend))
4447 tree new_friend_template_info;
4448 tree new_friend_result_template_info;
4450 int new_friend_is_defn;
4452 /* We must save some information from NEW_FRIEND before calling
4453 duplicate decls since that function will free NEW_FRIEND if
4455 new_friend_template_info = DECL_TEMPLATE_INFO (new_friend);
4456 if (TREE_CODE (new_friend) == TEMPLATE_DECL)
4458 /* This declaration is a `primary' template. */
4459 DECL_PRIMARY_TEMPLATE (new_friend) = new_friend;
4462 = DECL_INITIAL (DECL_RESULT (new_friend)) != NULL_TREE;
4463 new_friend_result_template_info
4464 = DECL_TEMPLATE_INFO (DECL_RESULT (new_friend));
4468 new_friend_is_defn = DECL_INITIAL (new_friend) != NULL_TREE;
4469 new_friend_result_template_info = NULL_TREE;
4472 /* Inside pushdecl_namespace_level, we will push into the
4473 current namespace. However, the friend function should go
4474 into the namespace of the template. */
4475 ns = decl_namespace_context (new_friend);
4476 push_nested_namespace (ns);
4477 old_decl = pushdecl_namespace_level (new_friend);
4478 pop_nested_namespace (ns);
4480 if (old_decl != new_friend)
4482 /* This new friend declaration matched an existing
4483 declaration. For example, given:
4485 template <class T> void f(T);
4486 template <class U> class C {
4487 template <class T> friend void f(T) {}
4490 the friend declaration actually provides the definition
4491 of `f', once C has been instantiated for some type. So,
4492 old_decl will be the out-of-class template declaration,
4493 while new_friend is the in-class definition.
4495 But, if `f' was called before this point, the
4496 instantiation of `f' will have DECL_TI_ARGS corresponding
4497 to `T' but not to `U', references to which might appear
4498 in the definition of `f'. Previously, the most general
4499 template for an instantiation of `f' was the out-of-class
4500 version; now it is the in-class version. Therefore, we
4501 run through all specialization of `f', adding to their
4502 DECL_TI_ARGS appropriately. In particular, they need a
4503 new set of outer arguments, corresponding to the
4504 arguments for this class instantiation.
4506 The same situation can arise with something like this:
4509 template <class T> class C {
4513 when `C<int>' is instantiated. Now, `f(int)' is defined
4516 if (!new_friend_is_defn)
4517 /* On the other hand, if the in-class declaration does
4518 *not* provide a definition, then we don't want to alter
4519 existing definitions. We can just leave everything
4524 /* Overwrite whatever template info was there before, if
4525 any, with the new template information pertaining to
4527 DECL_TEMPLATE_INFO (old_decl) = new_friend_template_info;
4529 if (TREE_CODE (old_decl) != TEMPLATE_DECL)
4530 /* duplicate_decls will take care of this case. */
4535 tree new_friend_args;
4537 DECL_TEMPLATE_INFO (DECL_RESULT (old_decl))
4538 = new_friend_result_template_info;
4540 new_friend_args = TI_ARGS (new_friend_template_info);
4541 for (t = DECL_TEMPLATE_SPECIALIZATIONS (old_decl);
4545 tree spec = TREE_VALUE (t);
4548 = add_outermost_template_args (new_friend_args,
4549 DECL_TI_ARGS (spec));
4552 /* Now, since specializations are always supposed to
4553 hang off of the most general template, we must move
4555 t = most_general_template (old_decl);
4558 DECL_TEMPLATE_SPECIALIZATIONS (t)
4559 = chainon (DECL_TEMPLATE_SPECIALIZATIONS (t),
4560 DECL_TEMPLATE_SPECIALIZATIONS (old_decl));
4561 DECL_TEMPLATE_SPECIALIZATIONS (old_decl) = NULL_TREE;
4566 /* The information from NEW_FRIEND has been merged into OLD_DECL
4567 by duplicate_decls. */
4568 new_friend = old_decl;
4571 else if (TYPE_SIZE (DECL_CONTEXT (new_friend)))
4573 /* Check to see that the declaration is really present, and,
4574 possibly obtain an improved declaration. */
4575 tree fn = check_classfn (DECL_CONTEXT (new_friend),
4584 input_filename = file;
4588 /* FRIEND_TMPL is a friend TEMPLATE_DECL. ARGS is the vector of
4589 template arguments, as for tsubst.
4591 Returns an appropriate tsbust'd friend type. */
4594 tsubst_friend_class (friend_tmpl, args)
4601 /* First, we look for a class template. */
4602 tmpl = lookup_name (DECL_NAME (friend_tmpl), /*prefer_type=*/0);
4604 /* But, if we don't find one, it might be because we're in a
4605 situation like this:
4613 Here, in the scope of (say) S<int>, `S' is bound to a TYPE_DECL
4614 for `S<int>', not the TEMPLATE_DECL. */
4615 if (!tmpl || !DECL_CLASS_TEMPLATE_P (tmpl))
4617 tmpl = lookup_name (DECL_NAME (friend_tmpl), /*prefer_type=*/1);
4618 tmpl = maybe_get_template_decl_from_type_decl (tmpl);
4621 if (tmpl && DECL_CLASS_TEMPLATE_P (tmpl))
4623 /* The friend template has already been declared. Just
4624 check to see that the declarations match, and install any new
4625 default parameters. We must tsubst the default parameters,
4626 of course. We only need the innermost template parameters
4627 because that is all that redeclare_class_template will look
4630 = tsubst_template_parms (DECL_TEMPLATE_PARMS (friend_tmpl),
4631 args, /*complain=*/1);
4632 redeclare_class_template (TREE_TYPE (tmpl), parms);
4633 friend_type = TREE_TYPE (tmpl);
4637 /* The friend template has not already been declared. In this
4638 case, the instantiation of the template class will cause the
4639 injection of this template into the global scope. */
4640 tmpl = tsubst (friend_tmpl, args, /*complain=*/1, NULL_TREE);
4642 /* The new TMPL is not an instantiation of anything, so we
4643 forget its origins. We don't reset CLASSTYPE_TI_TEMPLATE for
4644 the new type because that is supposed to be the corresponding
4645 template decl, i.e., TMPL. */
4646 DECL_USE_TEMPLATE (tmpl) = 0;
4647 DECL_TEMPLATE_INFO (tmpl) = NULL_TREE;
4648 CLASSTYPE_USE_TEMPLATE (TREE_TYPE (tmpl)) = 0;
4650 /* Inject this template into the global scope. */
4651 friend_type = TREE_TYPE (pushdecl_top_level (tmpl));
4658 instantiate_class_template (type)
4661 tree template, args, pattern, t;
4664 if (type == error_mark_node)
4665 return error_mark_node;
4667 if (TYPE_BEING_DEFINED (type) || TYPE_SIZE (type))
4670 /* Figure out which template is being instantiated. */
4671 template = most_general_template (CLASSTYPE_TI_TEMPLATE (type));
4672 my_friendly_assert (TREE_CODE (template) == TEMPLATE_DECL, 279);
4674 /* Figure out which arguments are being used to do the
4676 args = CLASSTYPE_TI_ARGS (type);
4677 PARTIAL_INSTANTIATION_P (type) = uses_template_parms (args);
4679 if (pedantic && PARTIAL_INSTANTIATION_P (type))
4680 /* If this is a partial instantiation, then we can't instantiate
4681 the type; there's no telling whether or not one of the
4682 template parameters might eventually be instantiated to some
4683 value that results in a specialization being used. For
4695 Now, the `S<U>' in `f<int>' is the specialization, not an
4696 instantiation of the original template. */
4699 /* Determine what specialization of the original template to
4701 if (PARTIAL_INSTANTIATION_P (type))
4702 /* There's no telling which specialization is appropriate at this
4703 point. Since all peeking at the innards of this partial
4704 instantiation are extensions (like the "implicit typename"
4705 extension, which allows users to omit the keyword `typename' on
4706 names that are declared as types in template base classes), we
4707 are free to do what we please.
4709 Trying to figure out which partial instantiation to use can
4710 cause a crash. (Some of the template arguments don't even have
4711 types.) So, we just use the most general version. */
4715 t = most_specialized_class (template, args);
4717 if (t == error_mark_node)
4719 const char *str = "candidates are:";
4720 cp_error ("ambiguous class template instantiation for `%#T'", type);
4721 for (t = DECL_TEMPLATE_SPECIALIZATIONS (template); t;
4724 if (get_class_bindings (TREE_VALUE (t), TREE_PURPOSE (t),
4727 cp_error_at ("%s %+#T", str, TREE_TYPE (t));
4731 TYPE_BEING_DEFINED (type) = 1;
4732 return error_mark_node;
4737 pattern = TREE_TYPE (t);
4739 pattern = TREE_TYPE (template);
4741 /* If the template we're instantiating is incomplete, then clearly
4742 there's nothing we can do. */
4743 if (TYPE_SIZE (pattern) == NULL_TREE)
4746 /* If this is a partial instantiation, don't tsubst anything. We will
4747 only use this type for implicit typename, so the actual contents don't
4748 matter. All that matters is whether a particular name is a type. */
4749 if (PARTIAL_INSTANTIATION_P (type))
4751 /* The fields set here must be kept in sync with those cleared
4752 in begin_class_definition. */
4753 TYPE_BINFO_BASETYPES (type) = TYPE_BINFO_BASETYPES (pattern);
4754 TYPE_FIELDS (type) = TYPE_FIELDS (pattern);
4755 TYPE_METHODS (type) = TYPE_METHODS (pattern);
4756 CLASSTYPE_TAGS (type) = CLASSTYPE_TAGS (pattern);
4757 /* Pretend that the type is complete, so that we will look
4758 inside it during name lookup and such. */
4759 TYPE_SIZE (type) = integer_zero_node;
4763 /* If we've recursively instantiated too many templates, stop. */
4764 if (! push_tinst_level (type))
4767 /* Now we're really doing the instantiation. Mark the type as in
4768 the process of being defined. */
4769 TYPE_BEING_DEFINED (type) = 1;
4771 maybe_push_to_top_level (uses_template_parms (type));
4775 /* This TYPE is actually a instantiation of of a partial
4776 specialization. We replace the innermost set of ARGS with
4777 the arguments appropriate for substitution. For example,
4780 template <class T> struct S {};
4781 template <class T> struct S<T*> {};
4783 and supposing that we are instantiating S<int*>, ARGS will
4784 present be {int*} but we need {int}. */
4786 = get_class_bindings (TREE_VALUE (t), TREE_PURPOSE (t),
4789 /* If there were multiple levels in ARGS, replacing the
4790 innermost level would alter CLASSTYPE_TI_ARGS, which we don't
4791 want, so we make a copy first. */
4792 if (TMPL_ARGS_HAVE_MULTIPLE_LEVELS (args))
4794 args = copy_node (args);
4795 SET_TMPL_ARGS_LEVEL (args, TMPL_ARGS_DEPTH (args), inner_args);
4801 if (flag_external_templates)
4803 if (flag_alt_external_templates)
4805 CLASSTYPE_INTERFACE_ONLY (type) = interface_only;
4806 SET_CLASSTYPE_INTERFACE_UNKNOWN_X (type, interface_unknown);
4807 CLASSTYPE_VTABLE_NEEDS_WRITING (type)
4808 = (! CLASSTYPE_INTERFACE_ONLY (type)
4809 && CLASSTYPE_INTERFACE_KNOWN (type));
4813 CLASSTYPE_INTERFACE_ONLY (type) = CLASSTYPE_INTERFACE_ONLY (pattern);
4814 SET_CLASSTYPE_INTERFACE_UNKNOWN_X
4815 (type, CLASSTYPE_INTERFACE_UNKNOWN (pattern));
4816 CLASSTYPE_VTABLE_NEEDS_WRITING (type)
4817 = (! CLASSTYPE_INTERFACE_ONLY (type)
4818 && CLASSTYPE_INTERFACE_KNOWN (type));
4823 SET_CLASSTYPE_INTERFACE_UNKNOWN (type);
4824 CLASSTYPE_VTABLE_NEEDS_WRITING (type) = 1;
4827 TYPE_HAS_CONSTRUCTOR (type) = TYPE_HAS_CONSTRUCTOR (pattern);
4828 TYPE_HAS_DESTRUCTOR (type) = TYPE_HAS_DESTRUCTOR (pattern);
4829 TYPE_OVERLOADS_CALL_EXPR (type) = TYPE_OVERLOADS_CALL_EXPR (pattern);
4830 TYPE_OVERLOADS_ARRAY_REF (type) = TYPE_OVERLOADS_ARRAY_REF (pattern);
4831 TYPE_OVERLOADS_ARROW (type) = TYPE_OVERLOADS_ARROW (pattern);
4832 TYPE_GETS_NEW (type) = TYPE_GETS_NEW (pattern);
4833 TYPE_GETS_DELETE (type) = TYPE_GETS_DELETE (pattern);
4834 TYPE_VEC_DELETE_TAKES_SIZE (type) = TYPE_VEC_DELETE_TAKES_SIZE (pattern);
4835 TYPE_HAS_ASSIGN_REF (type) = TYPE_HAS_ASSIGN_REF (pattern);
4836 TYPE_HAS_CONST_ASSIGN_REF (type) = TYPE_HAS_CONST_ASSIGN_REF (pattern);
4837 TYPE_HAS_ABSTRACT_ASSIGN_REF (type) = TYPE_HAS_ABSTRACT_ASSIGN_REF (pattern);
4838 TYPE_HAS_INIT_REF (type) = TYPE_HAS_INIT_REF (pattern);
4839 TYPE_HAS_CONST_INIT_REF (type) = TYPE_HAS_CONST_INIT_REF (pattern);
4840 TYPE_HAS_DEFAULT_CONSTRUCTOR (type) = TYPE_HAS_DEFAULT_CONSTRUCTOR (pattern);
4841 TYPE_HAS_CONVERSION (type) = TYPE_HAS_CONVERSION (pattern);
4842 TYPE_BASE_CONVS_MAY_REQUIRE_CODE_P (type)
4843 = TYPE_BASE_CONVS_MAY_REQUIRE_CODE_P (pattern);
4844 TYPE_USES_MULTIPLE_INHERITANCE (type)
4845 = TYPE_USES_MULTIPLE_INHERITANCE (pattern);
4846 TYPE_USES_VIRTUAL_BASECLASSES (type)
4847 = TYPE_USES_VIRTUAL_BASECLASSES (pattern);
4848 TYPE_PACKED (type) = TYPE_PACKED (pattern);
4849 TYPE_ALIGN (type) = TYPE_ALIGN (pattern);
4850 TYPE_FOR_JAVA (type) = TYPE_FOR_JAVA (pattern); /* For libjava's JArray<T> */
4851 if (ANON_AGGR_TYPE_P (pattern))
4852 SET_ANON_AGGR_TYPE_P (type);
4854 if (TYPE_BINFO_BASETYPES (pattern))
4856 tree base_list = NULL_TREE;
4857 tree pbases = TYPE_BINFO_BASETYPES (pattern);
4860 /* Substitute into each of the bases to determine the actual
4862 for (i = 0; i < TREE_VEC_LENGTH (pbases); ++i)
4868 pbase = TREE_VEC_ELT (pbases, i);
4870 /* Substitue to figure out the base class. */
4871 base = tsubst (BINFO_TYPE (pbase), args,
4872 /*complain=*/1, NULL_TREE);
4873 if (base == error_mark_node)
4876 /* Calculate the correct access node. */
4877 if (TREE_VIA_VIRTUAL (pbase))
4879 if (TREE_VIA_PUBLIC (pbase))
4880 access = access_public_virtual_node;
4881 else if (TREE_VIA_PROTECTED (pbase))
4882 access = access_protected_virtual_node;
4884 access = access_private_virtual_node;
4888 if (TREE_VIA_PUBLIC (pbase))
4889 access = access_public_node;
4890 else if (TREE_VIA_PROTECTED (pbase))
4891 access = access_protected_node;
4893 access = access_private_node;
4896 base_list = tree_cons (access, base, base_list);
4899 /* The list is now in reverse order; correct that. */
4900 base_list = nreverse (base_list);
4902 /* Now call xref_basetypes to set up all the base-class
4904 xref_basetypes (TREE_CODE (pattern) == RECORD_TYPE
4905 ? (CLASSTYPE_DECLARED_CLASS (pattern)
4906 ? class_type_node : record_type_node)
4908 DECL_NAME (TYPE_NAME (pattern)),
4913 /* Now that our base classes are set up, enter the scope of the
4914 class, so that name lookups into base classes, etc. will work
4915 corectly. This is precisely analagous to what we do in
4916 begin_class_definition when defining an ordinary non-template
4918 pushclass (type, 1);
4920 for (t = CLASSTYPE_TAGS (pattern); t; t = TREE_CHAIN (t))
4922 tree tag = TREE_VALUE (t);
4923 tree name = TYPE_IDENTIFIER (tag);
4926 newtag = tsubst (tag, args, /*complain=*/1, NULL_TREE);
4927 if (TREE_CODE (newtag) != ENUMERAL_TYPE)
4929 if (TYPE_LANG_SPECIFIC (tag) && CLASSTYPE_IS_TEMPLATE (tag))
4930 /* Unfortunately, lookup_template_class sets
4931 CLASSTYPE_IMPLICIT_INSTANTIATION for a partial
4932 instantiation (i.e., for the type of a member template
4933 class nested within a template class.) This behavior is
4934 required for maybe_process_partial_specialization to work
4935 correctly, but is not accurate in this case; the TAG is not
4936 an instantiation of anything. (The corresponding
4937 TEMPLATE_DECL is an instantiation, but the TYPE is not.) */
4938 CLASSTYPE_USE_TEMPLATE (newtag) = 0;
4940 /* Now, we call pushtag to put this NEWTAG into the scope of
4941 TYPE. We first set up the IDENTIFIER_TYPE_VALUE to avoid
4942 pushtag calling push_template_decl. We don't have to do
4943 this for enums because it will already have been done in
4946 SET_IDENTIFIER_TYPE_VALUE (name, newtag);
4947 pushtag (name, newtag, /*globalize=*/0);
4951 /* Don't replace enum constants here. */
4952 for (t = TYPE_FIELDS (pattern); t; t = TREE_CHAIN (t))
4953 if (TREE_CODE (t) != CONST_DECL)
4957 /* The the file and line for this declaration, to assist in
4958 error message reporting. Since we called push_tinst_level
4959 above, we don't need to restore these. */
4960 lineno = DECL_SOURCE_LINE (t);
4961 input_filename = DECL_SOURCE_FILE (t);
4963 r = tsubst (t, args, /*complain=*/1, NULL_TREE);
4964 if (TREE_CODE (r) == VAR_DECL)
4968 if (DECL_DEFINED_IN_CLASS_P (r))
4969 init = tsubst_expr (DECL_INITIAL (t), args,
4970 /*complain=*/1, NULL_TREE);
4974 finish_static_data_member_decl (r, init,
4975 /*asmspec_tree=*/NULL_TREE,
4978 if (DECL_DEFINED_IN_CLASS_P (r))
4979 check_static_variable_definition (r, TREE_TYPE (r));
4982 /* R will have a TREE_CHAIN if and only if it has already been
4983 processed by finish_member_declaration. This can happen
4984 if, for example, it is a TYPE_DECL for a class-scoped
4985 ENUMERAL_TYPE; such a thing will already have been added to
4986 the field list by tsubst_enum above. */
4987 if (!TREE_CHAIN (r))
4989 set_current_access_from_decl (r);
4990 finish_member_declaration (r);
4994 /* Set up the list (TYPE_METHODS) and vector (CLASSTYPE_METHOD_VEC)
4995 for this instantiation. */
4996 for (t = TYPE_METHODS (pattern); t; t = TREE_CHAIN (t))
4998 tree r = tsubst (t, args, /*complain=*/1, NULL_TREE);
4999 set_current_access_from_decl (r);
5000 finish_member_declaration (r);
5003 /* Construct the DECL_FRIENDLIST for the new class type. */
5004 typedecl = TYPE_MAIN_DECL (type);
5005 for (t = DECL_FRIENDLIST (TYPE_MAIN_DECL (pattern));
5011 for (friends = TREE_VALUE (t);
5012 friends != NULL_TREE;
5013 friends = TREE_CHAIN (friends))
5014 if (TREE_PURPOSE (friends) == error_mark_node)
5016 tsubst_friend_function (TREE_VALUE (friends),
5019 my_friendly_abort (20000216);
5022 for (t = CLASSTYPE_FRIEND_CLASSES (pattern);
5026 tree friend_type = TREE_VALUE (t);
5027 tree new_friend_type;
5029 if (TREE_CODE (friend_type) == TEMPLATE_DECL)
5030 new_friend_type = tsubst_friend_class (friend_type, args);
5031 else if (uses_template_parms (friend_type))
5032 new_friend_type = tsubst (friend_type, args, /*complain=*/1,
5036 tree ns = decl_namespace_context (TYPE_MAIN_DECL (friend_type));
5038 /* The call to xref_tag_from_type does injection for friend
5040 push_nested_namespace (ns);
5042 xref_tag_from_type (friend_type, NULL_TREE, 1);
5043 pop_nested_namespace (ns);
5046 if (TREE_CODE (friend_type) == TEMPLATE_DECL)
5047 /* Trick make_friend_class into realizing that the friend
5048 we're adding is a template, not an ordinary class. It's
5049 important that we use make_friend_class since it will
5050 perform some error-checking and output cross-reference
5052 ++processing_template_decl;
5054 make_friend_class (type, new_friend_type);
5056 if (TREE_CODE (friend_type) == TEMPLATE_DECL)
5057 --processing_template_decl;
5060 for (t = TYPE_FIELDS (type); t; t = TREE_CHAIN (t))
5061 if (TREE_CODE (t) == FIELD_DECL)
5063 TREE_TYPE (t) = complete_type (TREE_TYPE (t));
5064 require_complete_type (t);
5067 /* Set the file and line number information to whatever is given for
5068 the class itself. This puts error messages involving generated
5069 implicit functions at a predictable point, and the same point
5070 that would be used for non-template classes. */
5071 lineno = DECL_SOURCE_LINE (typedecl);
5072 input_filename = DECL_SOURCE_FILE (typedecl);
5074 unreverse_member_declarations (type);
5075 finish_struct_1 (type);
5076 CLASSTYPE_GOT_SEMICOLON (type) = 1;
5078 /* Clear this now so repo_template_used is happy. */
5079 TYPE_BEING_DEFINED (type) = 0;
5080 repo_template_used (type);
5082 /* Now that the class is complete, instantiate default arguments for
5083 any member functions. We don't do this earlier because the
5084 default arguments may reference members of the class. */
5085 if (!PRIMARY_TEMPLATE_P (template))
5086 for (t = TYPE_METHODS (type); t; t = TREE_CHAIN (t))
5087 if (TREE_CODE (t) == FUNCTION_DECL
5088 /* Implicitly generated member functions will not have tmplate
5089 information; they are not instantiations, but instead are
5090 created "fresh" for each instantiation. */
5091 && DECL_TEMPLATE_INFO (t))
5092 tsubst_default_arguments (t);
5095 pop_from_top_level ();
5105 if (t1 == NULL_TREE)
5106 return t2 == NULL_TREE;
5107 if (t2 == NULL_TREE)
5109 /* Don't care if one declares its arg const and the other doesn't -- the
5110 main variant of the arg type is all that matters. */
5111 if (TYPE_MAIN_VARIANT (TREE_VALUE (t1))
5112 != TYPE_MAIN_VARIANT (TREE_VALUE (t2)))
5114 return list_eq (TREE_CHAIN (t1), TREE_CHAIN (t2));
5117 /* If arg is a non-type template parameter that does not depend on template
5118 arguments, fold it like we weren't in the body of a template. */
5121 maybe_fold_nontype_arg (arg)
5124 /* If we're not in a template, ARG is already as simple as it's going to
5125 get, and trying to reprocess the trees will break. */
5126 if (! processing_template_decl)
5129 if (TREE_CODE_CLASS (TREE_CODE (arg)) != 't'
5130 && !uses_template_parms (arg))
5132 /* Sometimes, one of the args was an expression involving a
5133 template constant parameter, like N - 1. Now that we've
5134 tsubst'd, we might have something like 2 - 1. This will
5135 confuse lookup_template_class, so we do constant folding
5136 here. We have to unset processing_template_decl, to
5137 fool build_expr_from_tree() into building an actual
5140 int saved_processing_template_decl = processing_template_decl;
5141 processing_template_decl = 0;
5142 arg = fold (build_expr_from_tree (arg));
5143 processing_template_decl = saved_processing_template_decl;
5148 /* Return the TREE_VEC with the arguments for the innermost template header,
5149 where ARGS is either that or the VEC of VECs for all the
5153 innermost_args (args)
5156 return TMPL_ARGS_LEVEL (args, TMPL_ARGS_DEPTH (args));
5159 /* Substitute ARGS into the vector of template arguments T. */
5162 tsubst_template_arg_vector (t, args, complain)
5167 int len = TREE_VEC_LENGTH (t), need_new = 0, i;
5168 tree *elts = (tree *) alloca (len * sizeof (tree));
5170 bzero ((char *) elts, len * sizeof (tree));
5172 for (i = 0; i < len; i++)
5174 if (TREE_VEC_ELT (t, i) != NULL_TREE
5175 && TREE_CODE (TREE_VEC_ELT (t, i)) == TREE_VEC)
5176 elts[i] = tsubst_template_arg_vector (TREE_VEC_ELT (t, i),
5179 elts[i] = maybe_fold_nontype_arg
5180 (tsubst_expr (TREE_VEC_ELT (t, i), args, complain,
5183 if (elts[i] != TREE_VEC_ELT (t, i))
5190 t = make_tree_vec (len);
5191 for (i = 0; i < len; i++)
5192 TREE_VEC_ELT (t, i) = elts[i];
5197 /* Return the result of substituting ARGS into the template parameters
5198 given by PARMS. If there are m levels of ARGS and m + n levels of
5199 PARMS, then the result will contain n levels of PARMS. For
5200 example, if PARMS is `template <class T> template <class U>
5201 template <T*, U, class V>' and ARGS is {{int}, {double}} then the
5202 result will be `template <int*, double, class V>'. */
5205 tsubst_template_parms (parms, args, complain)
5213 for (new_parms = &r;
5214 TMPL_PARMS_DEPTH (parms) > TMPL_ARGS_DEPTH (args);
5215 new_parms = &(TREE_CHAIN (*new_parms)),
5216 parms = TREE_CHAIN (parms))
5219 make_tree_vec (TREE_VEC_LENGTH (TREE_VALUE (parms)));
5222 for (i = 0; i < TREE_VEC_LENGTH (new_vec); ++i)
5224 tree default_value =
5225 TREE_PURPOSE (TREE_VEC_ELT (TREE_VALUE (parms), i));
5227 TREE_VALUE (TREE_VEC_ELT (TREE_VALUE (parms), i));
5229 TREE_VEC_ELT (new_vec, i)
5230 = build_tree_list (tsubst (default_value, args, complain,
5232 tsubst (parm_decl, args, complain,
5237 tree_cons (build_int_2 (0, (TMPL_PARMS_DEPTH (parms)
5238 - TMPL_ARGS_DEPTH (args))),
5239 new_vec, NULL_TREE);
5245 /* Substitute the ARGS into the indicated aggregate (or enumeration)
5246 type T. If T is not an aggregate or enumeration type, it is
5247 handled as if by tsubst. IN_DECL is as for tsubst. If
5248 ENTERING_SCOPE is non-zero, T is the context for a template which
5249 we are presently tsubst'ing. Return the subsituted value. */
5252 tsubst_aggr_type (t, args, complain, in_decl, entering_scope)
5262 switch (TREE_CODE (t))
5265 if (TYPE_PTRMEMFUNC_P (t))
5267 tree r = build_ptrmemfunc_type
5268 (tsubst (TYPE_PTRMEMFUNC_FN_TYPE (t), args, complain, in_decl));
5269 return cp_build_qualified_type_real (r, TYPE_QUALS (t),
5273 /* else fall through */
5276 if (TYPE_TEMPLATE_INFO (t))
5282 /* First, determine the context for the type we are looking
5284 if (TYPE_CONTEXT (t) != NULL_TREE)
5285 context = tsubst_aggr_type (TYPE_CONTEXT (t), args,
5287 in_decl, /*entering_scope=*/1);
5289 context = NULL_TREE;
5291 /* Then, figure out what arguments are appropriate for the
5292 type we are trying to find. For example, given:
5294 template <class T> struct S;
5295 template <class T, class U> void f(T, U) { S<U> su; }
5297 and supposing that we are instantiating f<int, double>,
5298 then our ARGS will be {int, double}, but, when looking up
5299 S we only want {double}. */
5300 argvec = tsubst_template_arg_vector (TYPE_TI_ARGS (t), args,
5303 r = lookup_template_class (t, argvec, in_decl, context,
5306 return cp_build_qualified_type_real (r, TYPE_QUALS (t),
5310 /* This is not a template type, so there's nothing to do. */
5314 return tsubst (t, args, complain, in_decl);
5318 /* Substitute into the default argument ARG (a default argument for
5319 FN), which has the indicated TYPE. */
5322 tsubst_default_argument (fn, type, arg)
5327 /* This default argument came from a template. Instantiate the
5328 default argument here, not in tsubst. In the case of
5337 we must be careful to do name lookup in the scope of S<T>,
5338 rather than in the current class. */
5339 if (DECL_CLASS_SCOPE_P (fn))
5340 pushclass (DECL_CONTEXT (fn), 2);
5342 arg = tsubst_expr (arg, DECL_TI_ARGS (fn), /*complain=*/1, NULL_TREE);
5344 if (DECL_CLASS_SCOPE_P (fn))
5347 /* Make sure the default argument is reasonable. */
5348 arg = check_default_argument (type, arg);
5353 /* Substitute into all the default arguments for FN. */
5356 tsubst_default_arguments (fn)
5362 tmpl_args = DECL_TI_ARGS (fn);
5364 /* If this function is not yet instantiated, we certainly don't need
5365 its default arguments. */
5366 if (uses_template_parms (tmpl_args))
5369 for (arg = TYPE_ARG_TYPES (TREE_TYPE (fn));
5371 arg = TREE_CHAIN (arg))
5372 if (TREE_PURPOSE (arg))
5373 TREE_PURPOSE (arg) = tsubst_default_argument (fn,
5375 TREE_PURPOSE (arg));
5378 /* Substitute the ARGS into the T, which is a _DECL. TYPE is the
5379 (already computed) substitution of ARGS into TREE_TYPE (T), if
5380 appropriate. Return the result of the substitution. IN_DECL is as
5384 tsubst_decl (t, args, type, in_decl)
5391 char* saved_filename;
5394 /* Set the filename and linenumber to improve error-reporting. */
5395 saved_lineno = lineno;
5396 saved_filename = input_filename;
5397 lineno = DECL_SOURCE_LINE (t);
5398 input_filename = DECL_SOURCE_FILE (t);
5400 switch (TREE_CODE (t))
5404 /* We can get here when processing a member template function
5405 of a template class. */
5406 tree decl = DECL_TEMPLATE_RESULT (t);
5408 int is_template_template_parm = DECL_TEMPLATE_TEMPLATE_PARM_P (t);
5410 if (!is_template_template_parm)
5412 /* We might already have an instance of this template.
5413 The ARGS are for the surrounding class type, so the
5414 full args contain the tsubst'd args for the context,
5415 plus the innermost args from the template decl. */
5416 tree tmpl_args = DECL_CLASS_TEMPLATE_P (t)
5417 ? CLASSTYPE_TI_ARGS (TREE_TYPE (t))
5418 : DECL_TI_ARGS (DECL_RESULT (t));
5421 full_args = tsubst_template_arg_vector (tmpl_args, args,
5424 /* tsubst_template_arg_vector doesn't copy the vector if
5425 nothing changed. But, *something* should have
5427 my_friendly_assert (full_args != tmpl_args, 0);
5429 spec = retrieve_specialization (t, full_args);
5430 if (spec != NULL_TREE)
5437 /* Make a new template decl. It will be similar to the
5438 original, but will record the current template arguments.
5439 We also create a new function declaration, which is just
5440 like the old one, but points to this new template, rather
5441 than the old one. */
5444 my_friendly_assert (DECL_LANG_SPECIFIC (r) != 0, 0);
5445 TREE_CHAIN (r) = NULL_TREE;
5447 if (is_template_template_parm)
5449 tree new_decl = tsubst (decl, args, /*complain=*/1, in_decl);
5450 DECL_RESULT (r) = new_decl;
5451 TREE_TYPE (r) = TREE_TYPE (new_decl);
5456 = tsubst_aggr_type (DECL_CONTEXT (t), args,
5457 /*complain=*/1, in_decl,
5458 /*entering_scope=*/1);
5459 DECL_VIRTUAL_CONTEXT (r)
5460 = tsubst_aggr_type (DECL_VIRTUAL_CONTEXT (t), args,
5461 /*complain=*/1, in_decl,
5462 /*entering_scope=*/1);
5463 DECL_TEMPLATE_INFO (r) = build_tree_list (t, args);
5465 if (TREE_CODE (decl) == TYPE_DECL)
5467 tree new_type = tsubst (TREE_TYPE (t), args,
5468 /*complain=*/1, in_decl);
5469 TREE_TYPE (r) = new_type;
5470 CLASSTYPE_TI_TEMPLATE (new_type) = r;
5471 DECL_RESULT (r) = TYPE_MAIN_DECL (new_type);
5472 DECL_TI_ARGS (r) = CLASSTYPE_TI_ARGS (new_type);
5476 tree new_decl = tsubst (decl, args, /*complain=*/1, in_decl);
5477 DECL_RESULT (r) = new_decl;
5478 DECL_TI_TEMPLATE (new_decl) = r;
5479 TREE_TYPE (r) = TREE_TYPE (new_decl);
5480 DECL_TI_ARGS (r) = DECL_TI_ARGS (new_decl);
5483 SET_DECL_IMPLICIT_INSTANTIATION (r);
5484 DECL_TEMPLATE_INSTANTIATIONS (r) = NULL_TREE;
5485 DECL_TEMPLATE_SPECIALIZATIONS (r) = NULL_TREE;
5487 /* The template parameters for this new template are all the
5488 template parameters for the old template, except the
5489 outermost level of parameters. */
5490 DECL_TEMPLATE_PARMS (r)
5491 = tsubst_template_parms (DECL_TEMPLATE_PARMS (t), args,
5494 if (PRIMARY_TEMPLATE_P (t))
5495 DECL_PRIMARY_TEMPLATE (r) = r;
5497 /* We don't partially instantiate partial specializations. */
5498 if (TREE_CODE (decl) == TYPE_DECL)
5501 for (spec = DECL_TEMPLATE_SPECIALIZATIONS (t);
5503 spec = TREE_CHAIN (spec))
5505 /* It helps to consider example here. Consider:
5516 Now, for example, we are instantiating S<int>::f(U u).
5517 We want to make a template:
5522 It will have a specialization, for the case U = int*, of
5526 void S<int>::f<int*>(int*);
5528 This specialization will be an instantiation of
5529 the specialization given in the declaration of S, with
5530 argument list int*. */
5532 tree fn = TREE_VALUE (spec);
5536 if (!DECL_TEMPLATE_SPECIALIZATION (fn))
5537 /* Instantiations are on the same list, but they're of
5538 no concern to us. */
5541 if (TREE_CODE (fn) != TEMPLATE_DECL)
5542 /* A full specialization. There's no need to record
5546 spec_args = tsubst (DECL_TI_ARGS (fn), args,
5547 /*complain=*/1, in_decl);
5548 new_fn = tsubst (DECL_RESULT (most_general_template (fn)),
5549 spec_args, /*complain=*/1, in_decl);
5550 DECL_TI_TEMPLATE (new_fn) = fn;
5551 register_specialization (new_fn, r,
5552 innermost_args (spec_args));
5555 /* Record this partial instantiation. */
5556 register_specialization (r, t,
5557 DECL_TI_ARGS (DECL_RESULT (r)));
5565 tree argvec = NULL_TREE;
5572 /* Nobody should be tsubst'ing into non-template functions. */
5573 my_friendly_assert (DECL_TEMPLATE_INFO (t) != NULL_TREE, 0);
5575 if (TREE_CODE (DECL_TI_TEMPLATE (t)) == TEMPLATE_DECL)
5579 /* Calculate the most general template of which R is a
5580 specialization, and the complete set of arguments used to
5582 gen_tmpl = most_general_template (DECL_TI_TEMPLATE (t));
5584 = tsubst_template_arg_vector (DECL_TI_ARGS
5585 (DECL_TEMPLATE_RESULT (gen_tmpl)),
5586 args, /*complain=*/1);
5588 /* Check to see if we already have this specialization. */
5589 spec = retrieve_specialization (gen_tmpl, argvec);
5597 /* Here, we deal with the peculiar case:
5599 template <class T> struct S {
5600 template <class U> friend void f();
5602 template <class U> friend void f() {}
5604 template void f<double>();
5606 Here, the ARGS for the instantiation of will be {int,
5607 double}. But, we only need as many ARGS as there are
5608 levels of template parameters in CODE_PATTERN. We are
5609 careful not to get fooled into reducing the ARGS in
5612 template <class T> struct S { template <class U> void f(U); }
5613 template <class T> template <> void S<T>::f(int) {}
5615 which we can spot because the pattern will be a
5616 specialization in this case. */
5617 args_depth = TMPL_ARGS_DEPTH (args);
5619 TMPL_PARMS_DEPTH (DECL_TEMPLATE_PARMS (DECL_TI_TEMPLATE (t)));
5620 if (args_depth > parms_depth
5621 && !DECL_TEMPLATE_SPECIALIZATION (t))
5623 my_friendly_assert (DECL_FRIEND_P (t), 0);
5625 if (parms_depth > 1)
5629 args = make_tree_vec (parms_depth);
5630 for (i = 0; i < parms_depth; ++i)
5631 TREE_VEC_ELT (args, i) =
5632 TREE_VEC_ELT (args, i + (args_depth - parms_depth));
5635 args = TREE_VEC_ELT (args, args_depth - parms_depth);
5640 /* This special case arises when we have something like this:
5642 template <class T> struct S {
5643 friend void f<int>(int, double);
5646 Here, the DECL_TI_TEMPLATE for the friend declaration
5647 will be a LOOKUP_EXPR or an IDENTIFIER_NODE. We are
5648 being called from tsubst_friend_function, and we want
5649 only to create a new decl (R) with appropriate types so
5650 that we can call determine_specialization. */
5651 my_friendly_assert ((TREE_CODE (DECL_TI_TEMPLATE (t))
5653 || (TREE_CODE (DECL_TI_TEMPLATE (t))
5654 == IDENTIFIER_NODE), 0);
5655 gen_tmpl = NULL_TREE;
5658 if (DECL_CLASS_SCOPE_P (t))
5660 if (DECL_NAME (t) == constructor_name (DECL_CONTEXT (t)))
5664 ctx = tsubst_aggr_type (DECL_CONTEXT (t), args,
5666 /*entering_scope=*/1);
5671 ctx = DECL_CONTEXT (t);
5673 type = tsubst (type, args, /*complain=*/1, in_decl);
5674 if (type == error_mark_node)
5675 return error_mark_node;
5677 /* We do NOT check for matching decls pushed separately at this
5678 point, as they may not represent instantiations of this
5679 template, and in any case are considered separate under the
5680 discrete model. Instead, see add_maybe_template. */
5684 DECL_USE_TEMPLATE (r) = 0;
5685 TREE_TYPE (r) = type;
5687 DECL_CONTEXT (r) = ctx;
5688 DECL_VIRTUAL_CONTEXT (r)
5689 = tsubst_aggr_type (DECL_VIRTUAL_CONTEXT (t), args,
5691 /*entering_scope=*/1);
5693 if (member && IDENTIFIER_TYPENAME_P (DECL_NAME (r)))
5694 /* Type-conversion operator. Reconstruct the name, in
5695 case it's the name of one of the template's parameters. */
5696 DECL_NAME (r) = build_typename_overload (TREE_TYPE (type));
5698 DECL_ARGUMENTS (r) = tsubst (DECL_ARGUMENTS (t), args,
5700 DECL_MAIN_VARIANT (r) = r;
5701 DECL_RESULT (r) = NULL_TREE;
5703 TREE_STATIC (r) = 0;
5704 TREE_PUBLIC (r) = TREE_PUBLIC (t);
5705 DECL_EXTERNAL (r) = 1;
5706 DECL_INTERFACE_KNOWN (r) = 0;
5707 DECL_DEFER_OUTPUT (r) = 0;
5708 TREE_CHAIN (r) = NULL_TREE;
5709 DECL_PENDING_INLINE_INFO (r) = 0;
5710 DECL_PENDING_INLINE_P (r) = 0;
5713 /* Set up the DECL_TEMPLATE_INFO for R and compute its mangled
5714 name. There's no need to do this in the special friend
5715 case mentioned above where GEN_TMPL is NULL. */
5718 DECL_TEMPLATE_INFO (r)
5719 = tree_cons (gen_tmpl, argvec, NULL_TREE);
5720 SET_DECL_IMPLICIT_INSTANTIATION (r);
5721 register_specialization (r, gen_tmpl, argvec);
5723 /* Set the mangled name for R. */
5724 if (DECL_DESTRUCTOR_P (t))
5725 DECL_ASSEMBLER_NAME (r) = build_destructor_name (ctx);
5728 /* Instantiations of template functions must be mangled
5729 specially, in order to conform to 14.5.5.1
5730 [temp.over.link]. */
5731 tree tmpl = DECL_TI_TEMPLATE (t);
5733 /* TMPL will be NULL if this is a specialization of a
5734 member function of a template class. */
5735 if (name_mangling_version < 1
5736 || tmpl == NULL_TREE
5737 || (member && !is_member_template (tmpl)
5738 && !DECL_TEMPLATE_INFO (tmpl)))
5739 set_mangled_name_for_decl (r);
5741 set_mangled_name_for_template_decl (r);
5745 make_decl_rtl (r, NULL_PTR, 1);
5747 /* Like grokfndecl. If we don't do this, pushdecl will
5748 mess up our TREE_CHAIN because it doesn't find a
5749 previous decl. Sigh. */
5751 && ! uses_template_parms (r)
5752 && (IDENTIFIER_GLOBAL_VALUE (DECL_ASSEMBLER_NAME (r))
5754 SET_IDENTIFIER_GLOBAL_VALUE (DECL_ASSEMBLER_NAME (r), r);
5756 /* We're not supposed to instantiate default arguments
5757 until they are called, for a template. But, for a
5760 template <class T> void f ()
5761 { extern void g(int i = T()); }
5763 we should do the substitution when the template is
5764 instantiated. We handle the member function case in
5765 instantiate_class_template since the default arguments
5766 might refer to other members of the class. */
5768 && !PRIMARY_TEMPLATE_P (gen_tmpl)
5769 && !uses_template_parms (argvec))
5770 tsubst_default_arguments (r);
5773 /* Copy the list of befriending classes. */
5774 for (friends = &DECL_BEFRIENDING_CLASSES (r);
5776 friends = &TREE_CHAIN (*friends))
5778 *friends = copy_node (*friends);
5779 TREE_VALUE (*friends) = tsubst (TREE_VALUE (*friends),
5780 args, /*complain=*/1,
5784 if (DECL_CONSTRUCTOR_P (r))
5786 maybe_retrofit_in_chrg (r);
5787 grok_ctor_properties (ctx, r);
5789 else if (DECL_OVERLOADED_OPERATOR_P (r))
5790 grok_op_properties (r, DECL_VIRTUAL_P (r), DECL_FRIEND_P (r));
5797 TREE_TYPE (r) = type;
5798 c_apply_type_quals_to_decl (CP_TYPE_QUALS (type), r);
5800 if (TREE_CODE (DECL_INITIAL (r)) != TEMPLATE_PARM_INDEX)
5801 DECL_INITIAL (r) = TREE_TYPE (r);
5803 DECL_INITIAL (r) = tsubst (DECL_INITIAL (r), args,
5804 /*complain=*/1, in_decl);
5806 DECL_CONTEXT (r) = NULL_TREE;
5807 if (PROMOTE_PROTOTYPES
5808 && (TREE_CODE (type) == INTEGER_TYPE
5809 || TREE_CODE (type) == ENUMERAL_TYPE)
5810 && TYPE_PRECISION (type) < TYPE_PRECISION (integer_type_node))
5811 DECL_ARG_TYPE (r) = integer_type_node;
5813 TREE_CHAIN (r) = tsubst (TREE_CHAIN (t), args,
5814 /*complain=*/1, TREE_CHAIN (t));
5822 TREE_TYPE (r) = type;
5823 c_apply_type_quals_to_decl (CP_TYPE_QUALS (type), r);
5825 /* We don't have to set DECL_CONTEXT here; it is set by
5826 finish_member_declaration. */
5827 DECL_INITIAL (r) = tsubst_expr (DECL_INITIAL (t), args,
5828 /*complain=*/1, in_decl);
5829 TREE_CHAIN (r) = NULL_TREE;
5830 if (TREE_CODE (type) == VOID_TYPE)
5831 cp_error_at ("instantiation of `%D' as type void", r);
5839 = tsubst_copy (DECL_INITIAL (t), args, /*complain=*/1, in_decl);
5840 TREE_CHAIN (r) = NULL_TREE;
5845 if (DECL_IMPLICIT_TYPEDEF_P (t))
5847 /* For an implicit typedef, we just want the implicit
5848 typedef for the tsubst'd type. We've already got the
5849 tsubst'd type, as TYPE, so we just need it's associated
5851 r = TYPE_NAME (type);
5854 else if (!DECL_LANG_SPECIFIC (t))
5856 /* For a template type parameter, we don't have to do
5857 anything special. */
5858 r= TYPE_NAME (type);
5872 /* Nobody should be tsubst'ing into non-template variables. */
5873 my_friendly_assert (DECL_LANG_SPECIFIC (t)
5874 && DECL_TEMPLATE_INFO (t) != NULL_TREE, 0);
5876 if (TYPE_P (CP_DECL_CONTEXT (t)))
5877 ctx = tsubst_aggr_type (DECL_CONTEXT (t), args,
5879 in_decl, /*entering_scope=*/1);
5881 /* Subsequent calls to pushdecl will fill this in. */
5884 /* Check to see if we already have this specialization. */
5885 tmpl = DECL_TI_TEMPLATE (t);
5886 gen_tmpl = most_general_template (tmpl);
5887 argvec = tsubst (DECL_TI_ARGS (t), args, /*complain=*/1, in_decl);
5889 spec = retrieve_specialization (gen_tmpl, argvec);
5891 spec = retrieve_local_specialization (gen_tmpl,
5892 current_function_decl);
5900 /* This declaration is going to have to be around for a while,
5901 so me make sure it is on a saveable obstack. */
5904 TREE_TYPE (r) = type;
5905 c_apply_type_quals_to_decl (CP_TYPE_QUALS (type), r);
5906 DECL_CONTEXT (r) = ctx;
5908 /* Don't try to expand the initializer until someone tries to use
5909 this variable; otherwise we run into circular dependencies. */
5910 DECL_INITIAL (r) = NULL_TREE;
5915 /* For __PRETTY_FUNCTION__ we have to adjust the initializer. */
5916 if (DECL_PRETTY_FUNCTION_P (r))
5918 DECL_INITIAL (r) = tsubst (DECL_INITIAL (t),
5922 TREE_TYPE (r) = TREE_TYPE (DECL_INITIAL (r));
5925 /* If the template variable was marked TREE_ASM_WRITTEN, that
5926 means we don't need to write out any of the instantiations
5927 either. (__FUNCTION__ and its ilk are marked thusly.) */
5928 TREE_ASM_WRITTEN (r) = TREE_ASM_WRITTEN (t);
5930 /* Even if the original location is out of scope, the newly
5931 substituted one is not. */
5932 if (TREE_CODE (r) == VAR_DECL)
5933 DECL_DEAD_FOR_LOCAL (r) = 0;
5935 /* A static data member declaration is always marked external
5936 when it is declared in-class, even if an initializer is
5937 present. We mimic the non-template processing here. */
5939 DECL_EXTERNAL (r) = 1;
5941 DECL_TEMPLATE_INFO (r) = tree_cons (tmpl, argvec, NULL_TREE);
5942 SET_DECL_IMPLICIT_INSTANTIATION (r);
5944 register_specialization (r, gen_tmpl, argvec);
5946 register_local_specialization (r, gen_tmpl,
5947 current_function_decl);
5949 TREE_CHAIN (r) = NULL_TREE;
5950 if (TREE_CODE (r) == VAR_DECL && TREE_CODE (type) == VOID_TYPE)
5951 cp_error_at ("instantiation of `%D' as type void", r);
5956 my_friendly_abort (0);
5959 /* Restore the file and line information. */
5960 lineno = saved_lineno;
5961 input_filename = saved_filename;
5966 /* Substitue into the ARG_TYPES of a function type. */
5969 tsubst_arg_types (arg_types, args, complain, in_decl)
5975 tree remaining_arg_types;
5978 if (!arg_types || arg_types == void_list_node)
5981 remaining_arg_types = tsubst_arg_types (TREE_CHAIN (arg_types),
5982 args, complain, in_decl);
5983 if (remaining_arg_types == error_mark_node)
5984 return error_mark_node;
5986 type = tsubst (TREE_VALUE (arg_types), args, complain, in_decl);
5987 if (type == error_mark_node)
5988 return error_mark_node;
5990 /* Do array-to-pointer, function-to-pointer conversion, and ignore
5991 top-level qualifiers as required. */
5992 type = TYPE_MAIN_VARIANT (type_decays_to (type));
5994 /* Note that we do not substitute into default arguments here. The
5995 standard mandates that they be instantiated only when needed,
5996 which is done in build_over_call. */
5997 return hash_tree_cons (TREE_PURPOSE (arg_types), type,
5998 remaining_arg_types);
6002 /* Substitute into a FUNCTION_TYPE or METHOD_TYPE. This routine does
6003 *not* handle the exception-specification for FNTYPE, because the
6004 initial substitution of explicitly provided template parameters
6005 during argument deduction forbids substitution into the
6006 exception-specification:
6010 All references in the function type of the function template to the
6011 corresponding template parameters are replaced by the specified tem-
6012 plate argument values. If a substitution in a template parameter or
6013 in the function type of the function template results in an invalid
6014 type, type deduction fails. [Note: The equivalent substitution in
6015 exception specifications is done only when the function is instanti-
6016 ated, at which point a program is ill-formed if the substitution
6017 results in an invalid type.] */
6020 tsubst_function_type (t, args, complain, in_decl)
6030 /* The TYPE_CONTEXT is not used for function/method types. */
6031 my_friendly_assert (TYPE_CONTEXT (t) == NULL_TREE, 0);
6033 /* Substitue the return type. */
6034 return_type = tsubst (TREE_TYPE (t), args, complain, in_decl);
6035 if (return_type == error_mark_node)
6036 return error_mark_node;
6038 /* Substitue the argument types. */
6039 arg_types = tsubst_arg_types (TYPE_ARG_TYPES (t), args,
6041 if (arg_types == error_mark_node)
6042 return error_mark_node;
6044 /* Construct a new type node and return it. */
6045 if (TREE_CODE (t) == FUNCTION_TYPE)
6046 fntype = build_function_type (return_type, arg_types);
6049 tree r = TREE_TYPE (TREE_VALUE (arg_types));
6050 if (! IS_AGGR_TYPE (r))
6054 Type deduction may fail for any of the following
6057 -- Attempting to create "pointer to member of T" when T
6058 is not a class type. */
6060 cp_error ("creating pointer to member function of non-class type `%T'",
6062 return error_mark_node;
6065 fntype = build_cplus_method_type (r, return_type, TREE_CHAIN
6068 fntype = build_qualified_type (fntype, TYPE_QUALS (t));
6069 fntype = build_type_attribute_variant (fntype, TYPE_ATTRIBUTES (t));
6074 /* Substitute into the PARMS of a call-declarator. */
6077 tsubst_call_declarator_parms (parms, args, complain, in_decl)
6087 if (!parms || parms == void_list_node)
6090 new_parms = tsubst_call_declarator_parms (TREE_CHAIN (parms),
6091 args, complain, in_decl);
6093 /* Figure out the type of this parameter. */
6094 type = tsubst (TREE_VALUE (parms), args, complain, in_decl);
6096 /* Figure out the default argument as well. Note that we use
6097 tsubst_expr since the default argument is really an expression. */
6098 defarg = tsubst_expr (TREE_PURPOSE (parms), args, complain, in_decl);
6100 /* Chain this parameter on to the front of those we have already
6101 processed. We don't use hash_tree_cons because that function
6102 doesn't check TREE_PARMLIST. */
6103 new_parms = tree_cons (defarg, type, new_parms);
6105 /* And note that these are parameters. */
6106 TREE_PARMLIST (new_parms) = 1;
6111 /* Take the tree structure T and replace template parameters used
6112 therein with the argument vector ARGS. IN_DECL is an associated
6113 decl for diagnostics. If an error occurs, returns ERROR_MARK_NODE.
6114 An appropriate error message is issued only if COMPLAIN is
6115 non-zero. Note that we must be relatively non-tolerant of
6116 extensions here, in order to preserve conformance; if we allow
6117 substitutions that should not be allowed, we may allow argument
6118 deductions that should not succeed, and therefore report ambiguous
6119 overload situations where there are none. In theory, we could
6120 allow the substitution, but indicate that it should have failed,
6121 and allow our caller to make sure that the right thing happens, but
6122 we don't try to do this yet.
6124 This function is used for dealing with types, decls and the like;
6125 for expressions, use tsubst_expr or tsubst_copy. */
6128 tsubst (t, args, complain, in_decl)
6135 if (t == NULL_TREE || t == error_mark_node
6136 || t == integer_type_node
6137 || t == void_type_node
6138 || t == char_type_node
6139 || TREE_CODE (t) == NAMESPACE_DECL)
6142 if (TREE_CODE (t) == IDENTIFIER_NODE)
6143 type = IDENTIFIER_TYPE_VALUE (t);
6145 type = TREE_TYPE (t);
6146 if (type == unknown_type_node)
6147 my_friendly_abort (42);
6149 if (type && TREE_CODE (t) != FUNCTION_DECL
6150 && TREE_CODE (t) != TYPENAME_TYPE
6151 && TREE_CODE (t) != TEMPLATE_DECL
6152 && TREE_CODE (t) != IDENTIFIER_NODE
6153 && TREE_CODE (t) != FUNCTION_TYPE
6154 && TREE_CODE (t) != METHOD_TYPE)
6155 type = tsubst (type, args, complain, in_decl);
6156 if (type == error_mark_node)
6157 return error_mark_node;
6159 if (TREE_CODE_CLASS (TREE_CODE (t)) == 'd')
6160 return tsubst_decl (t, args, type, in_decl);
6162 switch (TREE_CODE (t))
6167 return tsubst_aggr_type (t, args, complain, in_decl,
6168 /*entering_scope=*/0);
6171 case IDENTIFIER_NODE:
6183 if (t == integer_type_node)
6186 if (TREE_CODE (TYPE_MIN_VALUE (t)) == INTEGER_CST
6187 && TREE_CODE (TYPE_MAX_VALUE (t)) == INTEGER_CST)
6191 tree max, omax = TREE_OPERAND (TYPE_MAX_VALUE (t), 0);
6193 max = tsubst_expr (omax, args, complain, in_decl);
6194 if (max == error_mark_node)
6195 return error_mark_node;
6197 /* See if we can reduce this expression to something simpler. */
6198 max = maybe_fold_nontype_arg (max);
6199 if (!processing_template_decl && TREE_READONLY_DECL_P (max))
6200 max = decl_constant_value (max);
6202 if (processing_template_decl
6203 /* When providing explicit arguments to a template
6204 function, but leaving some arguments for subsequent
6205 deduction, MAX may be template-dependent even if we're
6206 not PROCESSING_TEMPLATE_DECL. We still need to check for
6207 template parms, though; MAX won't be an INTEGER_CST for
6208 dynamic arrays, either. */
6209 || (TREE_CODE (max) != INTEGER_CST
6210 && uses_template_parms (max)))
6212 tree itype = make_node (INTEGER_TYPE);
6213 TYPE_MIN_VALUE (itype) = size_zero_node;
6214 TYPE_MAX_VALUE (itype) = build_min (MINUS_EXPR, sizetype, max,
6219 if (integer_zerop (omax))
6221 /* Still allow an explicit array of size zero. */
6223 pedwarn ("creating array with size zero");
6225 else if (integer_zerop (max)
6226 || (TREE_CODE (max) == INTEGER_CST
6227 && INT_CST_LT (max, integer_zero_node)))
6231 Type deduction may fail for any of the following
6234 Attempting to create an array with a size that is
6235 zero or negative. */
6237 cp_error ("creating array with size zero (`%E')", max);
6239 return error_mark_node;
6242 return compute_array_index_type (NULL_TREE, max);
6245 case TEMPLATE_TYPE_PARM:
6246 case TEMPLATE_TEMPLATE_PARM:
6247 case TEMPLATE_PARM_INDEX:
6255 if (TREE_CODE (t) == TEMPLATE_TYPE_PARM
6256 || TREE_CODE (t) == TEMPLATE_TEMPLATE_PARM)
6258 idx = TEMPLATE_TYPE_IDX (t);
6259 level = TEMPLATE_TYPE_LEVEL (t);
6263 idx = TEMPLATE_PARM_IDX (t);
6264 level = TEMPLATE_PARM_LEVEL (t);
6267 if (TREE_VEC_LENGTH (args) > 0)
6269 tree arg = NULL_TREE;
6271 levels = TMPL_ARGS_DEPTH (args);
6272 if (level <= levels)
6273 arg = TMPL_ARG (args, level, idx);
6275 if (arg == error_mark_node)
6276 return error_mark_node;
6277 else if (arg != NULL_TREE)
6279 if (TREE_CODE (t) == TEMPLATE_TYPE_PARM)
6281 my_friendly_assert (TREE_CODE_CLASS (TREE_CODE (arg))
6283 return cp_build_qualified_type_real
6284 (arg, CP_TYPE_QUALS (arg) | CP_TYPE_QUALS (t),
6287 else if (TREE_CODE (t) == TEMPLATE_TEMPLATE_PARM)
6289 if (TEMPLATE_TEMPLATE_PARM_TEMPLATE_INFO (t))
6291 /* We are processing a type constructed from
6292 a template template parameter */
6293 tree argvec = tsubst (TYPE_TI_ARGS (t),
6294 args, complain, in_decl);
6295 if (argvec == error_mark_node)
6296 return error_mark_node;
6298 /* We can get a TEMPLATE_TEMPLATE_PARM here when
6299 we are resolving nested-types in the signature of
6300 a member function templates.
6301 Otherwise ARG is a TEMPLATE_DECL and is the real
6302 template to be instantiated. */
6303 if (TREE_CODE (arg) == TEMPLATE_TEMPLATE_PARM)
6304 arg = TYPE_NAME (arg);
6306 r = lookup_template_class (DECL_NAME (arg),
6309 /*entering_scope=*/0);
6310 return cp_build_qualified_type_real (r,
6315 /* We are processing a template argument list. */
6323 my_friendly_abort (981018);
6326 /* This can happen during the attempted tsubst'ing in
6327 unify. This means that we don't yet have any information
6328 about the template parameter in question. */
6331 /* If we get here, we must have been looking at a parm for a
6332 more deeply nested template. Make a new version of this
6333 template parameter, but with a lower level. */
6334 switch (TREE_CODE (t))
6336 case TEMPLATE_TYPE_PARM:
6337 case TEMPLATE_TEMPLATE_PARM:
6339 TEMPLATE_TYPE_PARM_INDEX (r)
6340 = reduce_template_parm_level (TEMPLATE_TYPE_PARM_INDEX (t),
6342 TYPE_STUB_DECL (r) = TYPE_NAME (r) = TEMPLATE_TYPE_DECL (r);
6343 TYPE_MAIN_VARIANT (r) = r;
6344 TYPE_POINTER_TO (r) = NULL_TREE;
6345 TYPE_REFERENCE_TO (r) = NULL_TREE;
6347 if (TREE_CODE (t) == TEMPLATE_TEMPLATE_PARM
6348 && TEMPLATE_TEMPLATE_PARM_TEMPLATE_INFO (t))
6350 tree argvec = tsubst (TYPE_TI_ARGS (t), args,
6352 if (argvec == error_mark_node)
6353 return error_mark_node;
6355 TEMPLATE_TEMPLATE_PARM_TEMPLATE_INFO (r)
6356 = tree_cons (TYPE_NAME (t), argvec, NULL_TREE);
6360 case TEMPLATE_PARM_INDEX:
6361 r = reduce_template_parm_level (t, type, levels);
6365 my_friendly_abort (0);
6373 tree purpose, value, chain, result;
6375 if (t == void_list_node)
6378 purpose = TREE_PURPOSE (t);
6381 purpose = tsubst (purpose, args, complain, in_decl);
6382 if (purpose == error_mark_node)
6383 return error_mark_node;
6385 value = TREE_VALUE (t);
6388 value = tsubst (value, args, complain, in_decl);
6389 if (value == error_mark_node)
6390 return error_mark_node;
6392 chain = TREE_CHAIN (t);
6393 if (chain && chain != void_type_node)
6395 chain = tsubst (chain, args, complain, in_decl);
6396 if (chain == error_mark_node)
6397 return error_mark_node;
6399 if (purpose == TREE_PURPOSE (t)
6400 && value == TREE_VALUE (t)
6401 && chain == TREE_CHAIN (t))
6403 result = hash_tree_cons (purpose, value, chain);
6404 TREE_PARMLIST (result) = TREE_PARMLIST (t);
6408 if (type != NULL_TREE)
6410 /* A binfo node. We always need to make a copy, of the node
6411 itself and of its BINFO_BASETYPES. */
6415 /* Make sure type isn't a typedef copy. */
6416 type = BINFO_TYPE (TYPE_BINFO (type));
6418 TREE_TYPE (t) = complete_type (type);
6419 if (IS_AGGR_TYPE (type))
6421 BINFO_VTABLE (t) = TYPE_BINFO_VTABLE (type);
6422 BINFO_VIRTUALS (t) = TYPE_BINFO_VIRTUALS (type);
6423 if (TYPE_BINFO_BASETYPES (type) != NULL_TREE)
6424 BINFO_BASETYPES (t) = copy_node (TYPE_BINFO_BASETYPES (type));
6429 /* Otherwise, a vector of template arguments. */
6430 return tsubst_template_arg_vector (t, args, complain);
6433 case REFERENCE_TYPE:
6435 enum tree_code code;
6437 if (type == TREE_TYPE (t))
6440 code = TREE_CODE (t);
6445 Type deduction may fail for any of the following
6448 -- Attempting to create a pointer to reference type.
6449 -- Attempting to create a reference to a reference type or
6450 a reference to void. */
6451 if (TREE_CODE (type) == REFERENCE_TYPE
6452 || (code == REFERENCE_TYPE && TREE_CODE (type) == VOID_TYPE))
6454 static int last_line = 0;
6455 static char* last_file = 0;
6457 /* We keep track of the last time we issued this error
6458 message to avoid spewing a ton of messages during a
6459 single bad template instantiation. */
6460 if (complain && (last_line != lineno ||
6461 last_file != input_filename))
6463 if (TREE_CODE (type) == VOID_TYPE)
6464 cp_error ("forming reference to void");
6466 cp_error ("forming %s to reference type `%T'",
6467 (code == POINTER_TYPE) ? "pointer" : "reference",
6470 last_file = input_filename;
6473 return error_mark_node;
6475 else if (code == POINTER_TYPE)
6476 r = build_pointer_type (type);
6478 r = build_reference_type (type);
6479 r = cp_build_qualified_type_real (r, TYPE_QUALS (t), complain);
6481 /* Will this ever be needed for TYPE_..._TO values? */
6487 r = tsubst (TYPE_OFFSET_BASETYPE (t), args, complain, in_decl);
6488 if (r == error_mark_node || !IS_AGGR_TYPE (r))
6492 Type deduction may fail for any of the following
6495 -- Attempting to create "pointer to member of T" when T
6496 is not a class type. */
6498 cp_error ("creating pointer to member of non-class type `%T'",
6500 return error_mark_node;
6502 return build_offset_type (r, type);
6510 fntype = tsubst_function_type (t, args, complain, in_decl);
6511 if (fntype == error_mark_node)
6512 return error_mark_node;
6514 /* Substitue the exception specification. */
6515 raises = TYPE_RAISES_EXCEPTIONS (t);
6518 tree list = NULL_TREE;
6520 if (! TREE_VALUE (raises))
6523 for (; raises != NULL_TREE; raises = TREE_CHAIN (raises))
6525 tree spec = TREE_VALUE (raises);
6527 spec = tsubst (spec, args, complain, in_decl);
6528 if (spec == error_mark_node)
6530 list = add_exception_specifier (list, spec, complain);
6532 fntype = build_exception_variant (fntype, list);
6538 tree domain = tsubst (TYPE_DOMAIN (t), args, complain, in_decl);
6539 if (domain == error_mark_node)
6540 return error_mark_node;
6542 /* As an optimization, we avoid regenerating the array type if
6543 it will obviously be the same as T. */
6544 if (type == TREE_TYPE (t) && domain == TYPE_DOMAIN (t))
6547 /* These checks should match the ones in grokdeclarator.
6551 The deduction may fail for any of the following reasons:
6553 -- Attempting to create an array with an element type that
6554 is void, a function type, or a reference type. */
6555 if (TREE_CODE (type) == VOID_TYPE
6556 || TREE_CODE (type) == FUNCTION_TYPE
6557 || TREE_CODE (type) == REFERENCE_TYPE)
6560 cp_error ("creating array of `%T'", type);
6561 return error_mark_node;
6564 r = build_cplus_array_type (type, domain);
6571 tree e1 = tsubst (TREE_OPERAND (t, 0), args, complain,
6573 tree e2 = tsubst (TREE_OPERAND (t, 1), args, complain,
6576 if (e1 == error_mark_node || e2 == error_mark_node)
6577 return error_mark_node;
6579 return fold (build (TREE_CODE (t), TREE_TYPE (t), e1, e2));
6585 tree e = tsubst (TREE_OPERAND (t, 0), args, complain,
6587 if (e == error_mark_node)
6588 return error_mark_node;
6590 return fold (build (TREE_CODE (t), TREE_TYPE (t), e));
6595 tree ctx = tsubst_aggr_type (TYPE_CONTEXT (t), args, complain,
6596 in_decl, /*entering_scope=*/1);
6597 tree f = tsubst_copy (TYPENAME_TYPE_FULLNAME (t), args,
6600 if (ctx == error_mark_node || f == error_mark_node)
6601 return error_mark_node;
6603 if (!IS_AGGR_TYPE (ctx))
6606 cp_error ("`%T' is not a class, struct, or union type",
6608 return error_mark_node;
6610 else if (!uses_template_parms (ctx) && !TYPE_BEING_DEFINED (ctx))
6612 /* Normally, make_typename_type does not require that the CTX
6613 have complete type in order to allow things like:
6615 template <class T> struct S { typename S<T>::X Y; };
6617 But, such constructs have already been resolved by this
6618 point, so here CTX really should have complete type, unless
6619 it's a partial instantiation. */
6620 ctx = complete_type (ctx);
6621 if (!TYPE_SIZE (ctx))
6624 incomplete_type_error (NULL_TREE, ctx);
6625 return error_mark_node;
6629 f = make_typename_type (ctx, f, complain);
6630 if (f == error_mark_node)
6632 return cp_build_qualified_type_real (f,
6634 | CP_TYPE_QUALS (t),
6640 tree e = tsubst (TREE_OPERAND (t, 0), args, complain,
6642 if (e == error_mark_node)
6643 return error_mark_node;
6644 return make_pointer_declarator (type, e);
6649 tree e = tsubst (TREE_OPERAND (t, 0), args, complain,
6651 if (e == error_mark_node)
6652 return error_mark_node;
6653 return make_reference_declarator (type, e);
6658 tree e1 = tsubst (TREE_OPERAND (t, 0), args, complain,
6660 tree e2 = tsubst_expr (TREE_OPERAND (t, 1), args, complain,
6662 if (e1 == error_mark_node || e2 == error_mark_node)
6663 return error_mark_node;
6665 return build_parse_node (ARRAY_REF, e1, e2, tsubst_expr);
6670 tree e1 = tsubst (TREE_OPERAND (t, 0), args, complain,
6672 tree e2 = (tsubst_call_declarator_parms
6673 (CALL_DECLARATOR_PARMS (t), args, complain, in_decl));
6674 tree e3 = tsubst (CALL_DECLARATOR_EXCEPTION_SPEC (t), args,
6677 if (e1 == error_mark_node || e2 == error_mark_node
6678 || e3 == error_mark_node)
6679 return error_mark_node;
6681 return make_call_declarator (e1, e2, CALL_DECLARATOR_QUALS (t), e3);
6686 tree e1 = tsubst (TREE_OPERAND (t, 0), args, complain,
6688 tree e2 = tsubst (TREE_OPERAND (t, 1), args, complain, in_decl);
6689 if (e1 == error_mark_node || e2 == error_mark_node)
6690 return error_mark_node;
6692 return build_parse_node (TREE_CODE (t), e1, e2);
6697 tree e1 = tsubst_expr (TYPE_FIELDS (t), args, complain,
6699 if (e1 == error_mark_node)
6700 return error_mark_node;
6702 return TREE_TYPE (e1);
6712 /* This code should match declare_hidden_char_array in
6714 name = (*decl_printable_name) (current_function_decl, 2);
6715 len = strlen (name) + 1;
6716 type = build_array_type (char_type_node,
6717 build_index_type (build_int_2 (len, 0)));
6718 str = build_string (len, name);
6719 TREE_TYPE (str) = type;
6724 sorry ("use of `%s' in template",
6725 tree_code_name [(int) TREE_CODE (t)]);
6726 return error_mark_node;
6730 /* Like tsubst, but deals with expressions. This function just replaces
6731 template parms; to finish processing the resultant expression, use
6735 tsubst_copy (t, args, complain, in_decl)
6740 enum tree_code code;
6743 if (t == NULL_TREE || t == error_mark_node)
6746 code = TREE_CODE (t);
6751 return do_identifier (DECL_NAME (t), 0, NULL_TREE);
6758 if (!DECL_CONTEXT (t))
6759 /* This is a global enumeration constant. */
6762 /* Unfortunately, we cannot just call lookup_name here.
6765 template <int I> int f() {
6767 struct S { void g() { E e = a; } };
6770 When we instantiate f<7>::S::g(), say, lookup_name is not
6771 clever enough to find f<7>::a. */
6773 = tsubst_aggr_type (TREE_TYPE (t), args, complain, in_decl,
6774 /*entering_scope=*/0);
6776 for (v = TYPE_VALUES (enum_type);
6779 if (TREE_PURPOSE (v) == DECL_NAME (t))
6780 return TREE_VALUE (v);
6782 /* We didn't find the name. That should never happen; if
6783 name-lookup found it during preliminary parsing, we
6784 should find it again here during instantiation. */
6785 my_friendly_abort (0);
6790 if (DECL_CONTEXT (t))
6794 ctx = tsubst_aggr_type (DECL_CONTEXT (t), args, complain, in_decl,
6795 /*entering_scope=*/1);
6796 if (ctx != DECL_CONTEXT (t))
6797 return lookup_field (ctx, DECL_NAME (t), 0, 0);
6803 if (DECL_LANG_SPECIFIC (t) && DECL_TEMPLATE_INFO (t))
6804 t = tsubst (t, args, complain, in_decl);
6809 if (is_member_template (t))
6810 return tsubst (t, args, complain, in_decl);
6816 /* We must tsbust into a LOOKUP_EXPR in case the names to
6817 which it refers is a conversion operator; in that case the
6818 name will change. We avoid making unnecessary copies,
6821 tree id = tsubst_copy (TREE_OPERAND (t, 0), args, complain, in_decl);
6823 if (id != TREE_OPERAND (t, 0))
6825 r = build_nt (LOOKUP_EXPR, id);
6826 LOOKUP_EXPR_GLOBAL (r) = LOOKUP_EXPR_GLOBAL (t);
6834 case REINTERPRET_CAST_EXPR:
6835 case CONST_CAST_EXPR:
6836 case STATIC_CAST_EXPR:
6837 case DYNAMIC_CAST_EXPR:
6840 (code, tsubst (TREE_TYPE (t), args, complain, in_decl),
6841 tsubst_copy (TREE_OPERAND (t, 0), args, complain, in_decl));
6844 case PREDECREMENT_EXPR:
6845 case PREINCREMENT_EXPR:
6846 case POSTDECREMENT_EXPR:
6847 case POSTINCREMENT_EXPR:
6849 case TRUTH_NOT_EXPR:
6852 case CONVERT_EXPR: /* Unary + */
6861 (code, tsubst (TREE_TYPE (t), args, complain, in_decl),
6862 tsubst_copy (TREE_OPERAND (t, 0), args, complain, in_decl));
6867 case TRUNC_DIV_EXPR:
6869 case FLOOR_DIV_EXPR:
6870 case ROUND_DIV_EXPR:
6871 case EXACT_DIV_EXPR:
6873 case BIT_ANDTC_EXPR:
6876 case TRUNC_MOD_EXPR:
6877 case FLOOR_MOD_EXPR:
6878 case TRUTH_ANDIF_EXPR:
6879 case TRUTH_ORIF_EXPR:
6880 case TRUTH_AND_EXPR:
6901 (code, tsubst_copy (TREE_OPERAND (t, 0), args, complain, in_decl),
6902 tsubst_copy (TREE_OPERAND (t, 1), args, complain, in_decl));
6906 tree fn = TREE_OPERAND (t, 0);
6907 if (is_overloaded_fn (fn))
6908 fn = tsubst_copy (get_first_fn (fn), args, complain, in_decl);
6910 /* Sometimes FN is a LOOKUP_EXPR. */
6911 fn = tsubst_copy (fn, args, complain, in_decl);
6913 (code, fn, tsubst_copy (TREE_OPERAND (t, 1), args, complain,
6918 case METHOD_CALL_EXPR:
6920 tree name = TREE_OPERAND (t, 0);
6921 if (TREE_CODE (name) == BIT_NOT_EXPR)
6923 name = tsubst_copy (TREE_OPERAND (name, 0), args,
6925 name = build1 (BIT_NOT_EXPR, NULL_TREE, name);
6927 else if (TREE_CODE (name) == SCOPE_REF
6928 && TREE_CODE (TREE_OPERAND (name, 1)) == BIT_NOT_EXPR)
6930 tree base = tsubst_copy (TREE_OPERAND (name, 0), args,
6932 name = TREE_OPERAND (name, 1);
6933 name = tsubst_copy (TREE_OPERAND (name, 0), args,
6935 name = build1 (BIT_NOT_EXPR, NULL_TREE, name);
6936 name = build_nt (SCOPE_REF, base, name);
6939 name = tsubst_copy (TREE_OPERAND (t, 0), args, complain, in_decl);
6941 (code, name, tsubst_copy (TREE_OPERAND (t, 1), args,
6943 tsubst_copy (TREE_OPERAND (t, 2), args, complain, in_decl),
6948 /* This processing should really occur in tsubst_expr, However,
6949 tsubst_expr does not recurse into expressions, since it
6950 assumes that there aren't any statements inside them.
6951 Instead, it simply calls build_expr_from_tree. So, we need
6952 to expand the STMT_EXPR here. */
6953 if (!processing_template_decl)
6955 tree stmt_expr = begin_stmt_expr ();
6956 tsubst_expr (STMT_EXPR_STMT (t), args,
6958 return finish_stmt_expr (stmt_expr);
6965 case PSEUDO_DTOR_EXPR:
6968 (code, tsubst_copy (TREE_OPERAND (t, 0), args, complain, in_decl),
6969 tsubst_copy (TREE_OPERAND (t, 1), args, complain, in_decl),
6970 tsubst_copy (TREE_OPERAND (t, 2), args, complain, in_decl));
6977 (code, tsubst_copy (TREE_OPERAND (t, 0), args, complain, in_decl),
6978 tsubst_copy (TREE_OPERAND (t, 1), args, complain, in_decl),
6979 tsubst_copy (TREE_OPERAND (t, 2), args, complain, in_decl));
6980 NEW_EXPR_USE_GLOBAL (r) = NEW_EXPR_USE_GLOBAL (t);
6987 (code, tsubst_copy (TREE_OPERAND (t, 0), args, complain, in_decl),
6988 tsubst_copy (TREE_OPERAND (t, 1), args, complain, in_decl));
6989 DELETE_EXPR_USE_GLOBAL (r) = DELETE_EXPR_USE_GLOBAL (t);
6990 DELETE_EXPR_USE_VEC (r) = DELETE_EXPR_USE_VEC (t);
6994 case TEMPLATE_ID_EXPR:
6996 /* Substituted template arguments */
6997 tree targs = tsubst_copy (TREE_OPERAND (t, 1), args, complain,
7000 if (targs && TREE_CODE (targs) == TREE_LIST)
7003 for (chain = targs; chain; chain = TREE_CHAIN (chain))
7004 TREE_VALUE (chain) = maybe_fold_nontype_arg (TREE_VALUE (chain));
7009 for (i = 0; i < TREE_VEC_LENGTH (targs); ++i)
7010 TREE_VEC_ELT (targs, i)
7011 = maybe_fold_nontype_arg (TREE_VEC_ELT (targs, i));
7014 return lookup_template_function
7015 (tsubst_copy (TREE_OPERAND (t, 0), args, complain, in_decl), targs);
7020 tree purpose, value, chain;
7022 if (t == void_list_node)
7025 purpose = TREE_PURPOSE (t);
7027 purpose = tsubst_copy (purpose, args, complain, in_decl);
7028 value = TREE_VALUE (t);
7030 value = tsubst_copy (value, args, complain, in_decl);
7031 chain = TREE_CHAIN (t);
7032 if (chain && chain != void_type_node)
7033 chain = tsubst_copy (chain, args, complain, in_decl);
7034 if (purpose == TREE_PURPOSE (t)
7035 && value == TREE_VALUE (t)
7036 && chain == TREE_CHAIN (t))
7038 return tree_cons (purpose, value, chain);
7045 case TEMPLATE_TYPE_PARM:
7046 case TEMPLATE_TEMPLATE_PARM:
7047 case TEMPLATE_PARM_INDEX:
7049 case REFERENCE_TYPE:
7056 return tsubst (t, args, complain, in_decl);
7058 case IDENTIFIER_NODE:
7059 if (IDENTIFIER_TYPENAME_P (t)
7060 /* Make sure it's not just a variable named `__opr', for instance,
7061 which can occur in some existing code. */
7063 return build_typename_overload
7064 (tsubst (TREE_TYPE (t), args, complain, in_decl));
7071 (CONSTRUCTOR, tsubst (TREE_TYPE (t), args, complain, in_decl),
7072 NULL_TREE, tsubst_copy (CONSTRUCTOR_ELTS (t), args,
7073 complain, in_decl));
7074 TREE_HAS_CONSTRUCTOR (r) = TREE_HAS_CONSTRUCTOR (t);
7079 return build_va_arg (tsubst_copy (TREE_OPERAND (t, 0), args, complain,
7081 tsubst (TREE_TYPE (t), args, complain, in_decl));
7084 return tsubst (t, args, complain, in_decl);
7091 /* Like tsubst_copy, but also does semantic processing. */
7094 tsubst_expr (t, args, complain, in_decl)
7101 if (t == NULL_TREE || t == error_mark_node)
7104 if (processing_template_decl)
7105 return tsubst_copy (t, args, complain, in_decl);
7107 switch (TREE_CODE (t))
7111 finish_named_return_value
7112 (TREE_OPERAND (t, 0),
7113 tsubst_expr (TREE_OPERAND (t, 1), args, /*complain=*/1, in_decl));
7114 tsubst_expr (TREE_CHAIN (t), args, complain, in_decl);
7117 case CTOR_INITIALIZER:
7119 current_member_init_list
7120 = tsubst_expr_values (TREE_OPERAND (t, 0), args);
7121 current_base_init_list
7122 = tsubst_expr_values (TREE_OPERAND (t, 1), args);
7124 tsubst_expr (TREE_CHAIN (t), args, complain, in_decl);
7129 finish_return_stmt (tsubst_expr (RETURN_EXPR (t),
7130 args, complain, in_decl));
7135 finish_expr_stmt (tsubst_expr (EXPR_STMT_EXPR (t),
7136 args, complain, in_decl));
7145 decl = DECL_STMT_DECL (t);
7146 if (TREE_CODE (decl) == LABEL_DECL)
7147 finish_label_decl (DECL_NAME (decl));
7150 init = DECL_INITIAL (decl);
7151 decl = tsubst (decl, args, complain, in_decl);
7152 init = tsubst_expr (init, args, complain, in_decl);
7154 DECL_INITIAL (decl) = error_mark_node;
7155 /* By marking the declaration as instantiated, we avoid
7156 trying to instantiate it. Since instantiate_decl can't
7157 handle local variables, and since we've already done
7158 all that needs to be done, that's the right thing to
7160 if (TREE_CODE (decl) == VAR_DECL)
7161 DECL_TEMPLATE_INSTANTIATED (decl) = 1;
7162 maybe_push_decl (decl);
7163 cp_finish_decl (decl, init, NULL_TREE, 0);
7173 stmt = begin_for_stmt ();
7174 for (tmp = FOR_INIT_STMT (t); tmp; tmp = TREE_CHAIN (tmp))
7175 tsubst_expr (tmp, args, complain, in_decl);
7176 finish_for_init_stmt (stmt);
7177 finish_for_cond (tsubst_expr (FOR_COND (t), args,
7180 tmp = tsubst_expr (FOR_EXPR (t), args, complain, in_decl);
7181 finish_for_expr (tmp, stmt);
7182 tsubst_expr (FOR_BODY (t), args, complain, in_decl);
7183 finish_for_stmt (tmp, stmt);
7190 stmt = begin_while_stmt ();
7191 finish_while_stmt_cond (tsubst_expr (WHILE_COND (t),
7192 args, complain, in_decl),
7194 tsubst_expr (WHILE_BODY (t), args, complain, in_decl);
7195 finish_while_stmt (stmt);
7202 stmt = begin_do_stmt ();
7203 tsubst_expr (DO_BODY (t), args, complain, in_decl);
7204 finish_do_body (stmt);
7205 finish_do_stmt (tsubst_expr (DO_COND (t), args,
7216 stmt = begin_if_stmt ();
7217 finish_if_stmt_cond (tsubst_expr (IF_COND (t),
7218 args, complain, in_decl),
7221 if (tmp = THEN_CLAUSE (t), tmp)
7223 tsubst_expr (tmp, args, complain, in_decl);
7224 finish_then_clause (stmt);
7227 if (tmp = ELSE_CLAUSE (t), tmp)
7229 begin_else_clause ();
7230 tsubst_expr (tmp, args, complain, in_decl);
7231 finish_else_clause (stmt);
7243 stmt = begin_compound_stmt (COMPOUND_STMT_NO_SCOPE (t));
7244 for (substmt = COMPOUND_BODY (t);
7245 substmt != NULL_TREE;
7246 substmt = TREE_CHAIN (substmt))
7247 tsubst_expr (substmt, args, complain, in_decl);
7248 return finish_compound_stmt (COMPOUND_STMT_NO_SCOPE (t), stmt);
7254 finish_break_stmt ();
7259 finish_continue_stmt ();
7267 stmt = begin_switch_stmt ();
7268 val = tsubst_expr (SWITCH_COND (t), args, complain, in_decl);
7269 finish_switch_cond (val, stmt);
7270 tsubst_expr (SWITCH_BODY (t), args, complain, in_decl);
7271 finish_switch_stmt (val, stmt);
7277 finish_case_label (tsubst_expr (CASE_LOW (t), args, complain, in_decl),
7278 tsubst_expr (CASE_HIGH (t), args, complain, in_decl));
7282 lineno = STMT_LINENO (t);
7283 finish_label_stmt (DECL_NAME (LABEL_STMT_LABEL (t)));
7288 t = GOTO_DESTINATION (t);
7289 if (TREE_CODE (t) != LABEL_DECL)
7290 /* Computed goto's must be tsubst'd into. On the other hand,
7291 non-computed gotos must not be; the identifier in question
7292 will have no binding. */
7293 t = tsubst_expr (t, args, complain, in_decl);
7296 finish_goto_stmt (t);
7301 finish_asm_stmt (ASM_CV_QUAL (t),
7302 tsubst_expr (ASM_STRING (t), args, complain, in_decl),
7303 tsubst_expr (ASM_OUTPUTS (t), args, complain, in_decl),
7304 tsubst_expr (ASM_INPUTS (t), args, complain, in_decl),
7305 tsubst_expr (ASM_CLOBBERS (t), args, complain,
7313 stmt = begin_try_block ();
7314 tsubst_expr (TRY_STMTS (t), args, complain, in_decl);
7315 finish_cleanup_try_block (stmt);
7316 finish_cleanup (tsubst_expr (TRY_HANDLERS (t), args,
7324 if (FN_TRY_BLOCK_P (t))
7325 stmt = begin_function_try_block ();
7327 stmt = begin_try_block ();
7329 tsubst_expr (TRY_STMTS (t), args, complain, in_decl);
7331 if (FN_TRY_BLOCK_P (t))
7332 finish_function_try_block (stmt);
7334 finish_try_block (stmt);
7336 handler = TRY_HANDLERS (t);
7337 for (; handler; handler = TREE_CHAIN (handler))
7338 tsubst_expr (handler, args, complain, in_decl);
7339 if (FN_TRY_BLOCK_P (t))
7340 finish_function_handler_sequence (stmt);
7342 finish_handler_sequence (stmt);
7352 stmt = begin_handler ();
7353 if (HANDLER_PARMS (t))
7355 decl = DECL_STMT_DECL (HANDLER_PARMS (t));
7356 decl = tsubst (decl, args, complain, in_decl);
7357 /* Prevent instantiate_decl from trying to instantiate
7358 this variable. We've already done all that needs to be
7360 DECL_TEMPLATE_INSTANTIATED (decl) = 1;
7364 blocks = finish_handler_parms (decl, stmt);
7365 tsubst_expr (HANDLER_BODY (t), args, complain, in_decl);
7366 finish_handler (blocks, stmt);
7373 tsubst (t, args, complain, NULL_TREE);
7377 return build_expr_from_tree (tsubst_copy (t, args, complain, in_decl));
7382 /* Instantiate the indicated variable or function template TMPL with
7383 the template arguments in TARG_PTR. */
7386 instantiate_template (tmpl, targ_ptr)
7387 tree tmpl, targ_ptr;
7395 if (tmpl == error_mark_node)
7396 return error_mark_node;
7398 my_friendly_assert (TREE_CODE (tmpl) == TEMPLATE_DECL, 283);
7400 /* Check to see if we already have this specialization. */
7401 spec = retrieve_specialization (tmpl, targ_ptr);
7402 if (spec != NULL_TREE)
7405 if (DECL_TEMPLATE_INFO (tmpl))
7407 /* The TMPL is a partial instantiation. To get a full set of
7408 arguments we must add the arguments used to perform the
7409 partial instantiation. */
7410 targ_ptr = add_outermost_template_args (DECL_TI_ARGS (tmpl),
7412 gen_tmpl = most_general_template (tmpl);
7414 /* Check to see if we already have this specialization. */
7415 spec = retrieve_specialization (gen_tmpl, targ_ptr);
7416 if (spec != NULL_TREE)
7422 len = DECL_NTPARMS (gen_tmpl);
7423 inner_args = innermost_args (targ_ptr);
7427 tree t = TREE_VEC_ELT (inner_args, i);
7428 if (TREE_CODE_CLASS (TREE_CODE (t)) == 't')
7430 tree nt = target_type (t);
7431 if (IS_AGGR_TYPE (nt) && decl_function_context (TYPE_MAIN_DECL (nt)))
7433 cp_error ("type `%T' composed from a local class is not a valid template-argument", t);
7434 cp_error (" trying to instantiate `%D'", gen_tmpl);
7435 fndecl = error_mark_node;
7441 /* substitute template parameters */
7442 fndecl = tsubst (DECL_RESULT (gen_tmpl), targ_ptr, /*complain=*/1, gen_tmpl);
7443 /* The DECL_TI_TEMPLATE should always be the immediate parent
7444 template, not the most general template. */
7445 DECL_TI_TEMPLATE (fndecl) = tmpl;
7447 if (flag_external_templates)
7448 add_pending_template (fndecl);
7454 /* Push the name of the class template into the scope of the instantiation. */
7457 overload_template_name (type)
7460 tree id = DECL_NAME (CLASSTYPE_TI_TEMPLATE (type));
7463 if (IDENTIFIER_CLASS_VALUE (id)
7464 && TREE_TYPE (IDENTIFIER_CLASS_VALUE (id)) == type)
7467 decl = build_decl (TYPE_DECL, id, type);
7468 SET_DECL_ARTIFICIAL (decl);
7469 pushdecl_class_level (decl);
7472 /* The FN is a TEMPLATE_DECL for a function. The ARGS are the
7473 arguments that are being used when calling it. TARGS is a vector
7474 into which the deduced template arguments are placed.
7476 Return zero for success, 2 for an incomplete match that doesn't resolve
7477 all the types, and 1 for complete failure. An error message will be
7478 printed only for an incomplete match.
7480 If FN is a conversion operator, RETURN_TYPE is the type desired as
7481 the result of the conversion operator.
7483 TPARMS is a vector of template parameters.
7485 The EXPLICIT_TARGS are explicit template arguments provided via a
7488 The parameter STRICT is one of:
7491 We are deducing arguments for a function call, as in
7495 We are deducing arguments for a conversion function, as in
7499 We are deducing arguments when calculating the partial
7500 ordering between specializations of function or class
7501 templates, as in [temp.func.order] and [temp.class.order],
7502 when doing an explicit instantiation as in [temp.explicit],
7503 when determining an explicit specialization as in
7504 [temp.expl.spec], or when taking the address of a function
7505 template, as in [temp.deduct.funcaddr].
7507 The other arguments are as for type_unification. */
7510 fn_type_unification (fn, explicit_targs, targs, args, return_type,
7512 tree fn, explicit_targs, targs, args, return_type;
7513 unification_kind_t strict;
7519 my_friendly_assert (TREE_CODE (fn) == TEMPLATE_DECL, 0);
7521 fntype = TREE_TYPE (fn);
7526 The specified template arguments must match the template
7527 parameters in kind (i.e., type, nontype, template), and there
7528 must not be more arguments than there are parameters;
7529 otherwise type deduction fails.
7531 Nontype arguments must match the types of the corresponding
7532 nontype template parameters, or must be convertible to the
7533 types of the corresponding nontype parameters as specified in
7534 _temp.arg.nontype_, otherwise type deduction fails.
7536 All references in the function type of the function template
7537 to the corresponding template parameters are replaced by the
7538 specified template argument values. If a substitution in a
7539 template parameter or in the function type of the function
7540 template results in an invalid type, type deduction fails. */
7542 tree converted_args;
7545 = (coerce_template_parms (DECL_INNERMOST_TEMPLATE_PARMS (fn),
7546 explicit_targs, NULL_TREE, /*complain=*/0,
7547 /*require_all_arguments=*/0));
7548 if (converted_args == error_mark_node)
7551 fntype = tsubst (fntype, converted_args, /*complain=*/0, NULL_TREE);
7552 if (fntype == error_mark_node)
7555 /* Place the explicitly specified arguments in TARGS. */
7556 for (i = 0; i < TREE_VEC_LENGTH (targs); i++)
7557 TREE_VEC_ELT (targs, i) = TREE_VEC_ELT (converted_args, i);
7560 parms = TYPE_ARG_TYPES (fntype);
7562 if (DECL_CONV_FN_P (fn))
7564 /* This is a template conversion operator. Use the return types
7565 as well as the argument types. We use it instead of 'this', since
7566 we could be comparing conversions from different classes. */
7567 parms = tree_cons (NULL_TREE, TREE_TYPE (fntype),
7568 TREE_CHAIN (parms));
7569 args = tree_cons (NULL_TREE, return_type, TREE_CHAIN (args));
7572 /* We allow incomplete unification without an error message here
7573 because the standard doesn't seem to explicitly prohibit it. Our
7574 callers must be ready to deal with unification failures in any
7576 result = type_unification_real (DECL_INNERMOST_TEMPLATE_PARMS (fn),
7577 targs, parms, args, /*subr=*/0,
7578 strict, /*allow_incomplete*/1);
7581 /* All is well so far. Now, check:
7585 When all template arguments have been deduced, all uses of
7586 template parameters in nondeduced contexts are replaced with
7587 the corresponding deduced argument values. If the
7588 substitution results in an invalid type, as described above,
7589 type deduction fails. */
7590 if (tsubst (TREE_TYPE (fn), targs, /*complain=*/0, NULL_TREE)
7597 /* Adjust types before performing type deduction, as described in
7598 [temp.deduct.call] and [temp.deduct.conv]. The rules in these two
7599 sections are symmetric. PARM is the type of a function parameter
7600 or the return type of the conversion function. ARG is the type of
7601 the argument passed to the call, or the type of the value
7602 intialized with the result of the conversion function. */
7605 maybe_adjust_types_for_deduction (strict, parm, arg)
7606 unification_kind_t strict;
7617 /* Swap PARM and ARG throughout the remainder of this
7618 function; the handling is precisely symmetric since PARM
7619 will initialize ARG rather than vice versa. */
7627 /* There is nothing to do in this case. */
7631 my_friendly_abort (0);
7634 if (TREE_CODE (*parm) != REFERENCE_TYPE)
7636 /* [temp.deduct.call]
7638 If P is not a reference type:
7640 --If A is an array type, the pointer type produced by the
7641 array-to-pointer standard conversion (_conv.array_) is
7642 used in place of A for type deduction; otherwise,
7644 --If A is a function type, the pointer type produced by
7645 the function-to-pointer standard conversion
7646 (_conv.func_) is used in place of A for type deduction;
7649 --If A is a cv-qualified type, the top level
7650 cv-qualifiers of A's type are ignored for type
7652 if (TREE_CODE (*arg) == ARRAY_TYPE)
7653 *arg = build_pointer_type (TREE_TYPE (*arg));
7654 else if (TREE_CODE (*arg) == FUNCTION_TYPE)
7655 *arg = build_pointer_type (*arg);
7657 *arg = TYPE_MAIN_VARIANT (*arg);
7660 /* [temp.deduct.call]
7662 If P is a cv-qualified type, the top level cv-qualifiers
7663 of P's type are ignored for type deduction. If P is a
7664 reference type, the type referred to by P is used for
7666 *parm = TYPE_MAIN_VARIANT (*parm);
7667 if (TREE_CODE (*parm) == REFERENCE_TYPE)
7668 *parm = TREE_TYPE (*parm);
7671 /* Like type_unfication.
7673 If SUBR is 1, we're being called recursively (to unify the
7674 arguments of a function or method parameter of a function
7678 type_unification_real (tparms, targs, parms, args, subr,
7679 strict, allow_incomplete)
7680 tree tparms, targs, parms, args;
7682 unification_kind_t strict;
7683 int allow_incomplete;
7687 int ntparms = TREE_VEC_LENGTH (tparms);
7690 my_friendly_assert (TREE_CODE (tparms) == TREE_VEC, 289);
7691 my_friendly_assert (parms == NULL_TREE
7692 || TREE_CODE (parms) == TREE_LIST, 290);
7693 /* ARGS could be NULL (via a call from parse.y to
7694 build_x_function_call). */
7696 my_friendly_assert (TREE_CODE (args) == TREE_LIST, 291);
7697 my_friendly_assert (ntparms > 0, 292);
7702 sub_strict = UNIFY_ALLOW_MORE_CV_QUAL | UNIFY_ALLOW_DERIVED;
7706 sub_strict = UNIFY_ALLOW_LESS_CV_QUAL;
7710 sub_strict = UNIFY_ALLOW_NONE;
7714 my_friendly_abort (0);
7718 && parms != void_list_node
7720 && args != void_list_node)
7722 parm = TREE_VALUE (parms);
7723 parms = TREE_CHAIN (parms);
7724 arg = TREE_VALUE (args);
7725 args = TREE_CHAIN (args);
7727 if (arg == error_mark_node)
7729 if (arg == unknown_type_node)
7730 /* We can't deduce anything from this, but we might get all the
7731 template args from other function args. */
7734 /* Conversions will be performed on a function argument that
7735 corresponds with a function parameter that contains only
7736 non-deducible template parameters and explicitly specified
7737 template parameters. */
7738 if (! uses_template_parms (parm))
7742 if (TREE_CODE_CLASS (TREE_CODE (arg)) != 't')
7743 type = TREE_TYPE (arg);
7750 if (strict == DEDUCE_EXACT)
7752 if (same_type_p (parm, type))
7756 /* It might work; we shouldn't check now, because we might
7757 get into infinite recursion. Overload resolution will
7764 if (TREE_CODE_CLASS (TREE_CODE (arg)) != 't')
7766 my_friendly_assert (TREE_TYPE (arg) != NULL_TREE, 293);
7767 if (type_unknown_p (arg))
7769 /* [temp.deduct.type] A template-argument can be deduced from
7770 a pointer to function or pointer to member function
7771 argument if the set of overloaded functions does not
7772 contain function templates and at most one of a set of
7773 overloaded functions provides a unique match. */
7775 if (resolve_overloaded_unification
7776 (tparms, targs, parm, arg, strict, sub_strict)
7781 arg = TREE_TYPE (arg);
7785 maybe_adjust_types_for_deduction (strict, &parm, &arg);
7787 switch (unify (tparms, targs, parm, arg, sub_strict))
7795 /* Fail if we've reached the end of the parm list, and more args
7796 are present, and the parm list isn't variadic. */
7797 if (args && args != void_list_node && parms == void_list_node)
7799 /* Fail if parms are left and they don't have default values. */
7801 && parms != void_list_node
7802 && TREE_PURPOSE (parms) == NULL_TREE)
7805 for (i = 0; i < ntparms; i++)
7806 if (TREE_VEC_ELT (targs, i) == NULL_TREE)
7808 if (!allow_incomplete)
7809 error ("incomplete type unification");
7815 /* Subroutine of type_unification_real. Args are like the variables at the
7816 call site. ARG is an overloaded function (or template-id); we try
7817 deducing template args from each of the overloads, and if only one
7818 succeeds, we go with that. Modifies TARGS and returns 0 on success. */
7821 resolve_overloaded_unification (tparms, targs, parm, arg, strict,
7823 tree tparms, targs, parm, arg;
7824 unification_kind_t strict;
7827 tree tempargs = copy_node (targs);
7830 if (TREE_CODE (arg) == ADDR_EXPR)
7831 arg = TREE_OPERAND (arg, 0);
7833 if (TREE_CODE (arg) == COMPONENT_REF)
7834 /* Handle `&x' where `x' is some static or non-static member
7836 arg = TREE_OPERAND (arg, 1);
7838 if (TREE_CODE (arg) == OFFSET_REF)
7839 arg = TREE_OPERAND (arg, 1);
7841 /* Strip baselink information. */
7842 while (TREE_CODE (arg) == TREE_LIST)
7843 arg = TREE_VALUE (arg);
7845 if (TREE_CODE (arg) == TEMPLATE_ID_EXPR)
7847 /* If we got some explicit template args, we need to plug them into
7848 the affected templates before we try to unify, in case the
7849 explicit args will completely resolve the templates in question. */
7851 tree expl_subargs = TREE_OPERAND (arg, 1);
7852 arg = TREE_OPERAND (arg, 0);
7854 for (; arg; arg = OVL_NEXT (arg))
7856 tree fn = OVL_CURRENT (arg);
7859 if (TREE_CODE (fn) != TEMPLATE_DECL)
7862 subargs = get_bindings_overload (fn, DECL_RESULT (fn), expl_subargs);
7865 elem = tsubst (TREE_TYPE (fn), subargs, /*complain=*/0,
7867 if (TREE_CODE (elem) == METHOD_TYPE)
7868 elem = build_ptrmemfunc_type (build_pointer_type (elem));
7869 good += try_one_overload (tparms, targs, tempargs, parm, elem,
7870 strict, sub_strict);
7874 else if (TREE_CODE (arg) == OVERLOAD)
7876 for (; arg; arg = OVL_NEXT (arg))
7878 tree type = TREE_TYPE (OVL_CURRENT (arg));
7879 if (TREE_CODE (type) == METHOD_TYPE)
7880 type = build_ptrmemfunc_type (build_pointer_type (type));
7881 good += try_one_overload (tparms, targs, tempargs, parm,
7883 strict, sub_strict);
7887 my_friendly_abort (981006);
7889 /* [temp.deduct.type] A template-argument can be deduced from a pointer
7890 to function or pointer to member function argument if the set of
7891 overloaded functions does not contain function templates and at most
7892 one of a set of overloaded functions provides a unique match.
7894 So if we found multiple possibilities, we return success but don't
7899 int i = TREE_VEC_LENGTH (targs);
7901 if (TREE_VEC_ELT (tempargs, i))
7902 TREE_VEC_ELT (targs, i) = TREE_VEC_ELT (tempargs, i);
7910 /* Subroutine of resolve_overloaded_unification; does deduction for a single
7911 overload. Fills TARGS with any deduced arguments, or error_mark_node if
7912 different overloads deduce different arguments for a given parm.
7913 Returns 1 on success. */
7916 try_one_overload (tparms, orig_targs, targs, parm, arg, strict,
7918 tree tparms, orig_targs, targs, parm, arg;
7919 unification_kind_t strict;
7926 /* [temp.deduct.type] A template-argument can be deduced from a pointer
7927 to function or pointer to member function argument if the set of
7928 overloaded functions does not contain function templates and at most
7929 one of a set of overloaded functions provides a unique match.
7931 So if this is a template, just return success. */
7933 if (uses_template_parms (arg))
7936 maybe_adjust_types_for_deduction (strict, &parm, &arg);
7938 /* We don't copy orig_targs for this because if we have already deduced
7939 some template args from previous args, unify would complain when we
7940 try to deduce a template parameter for the same argument, even though
7941 there isn't really a conflict. */
7942 nargs = TREE_VEC_LENGTH (targs);
7943 tempargs = make_tree_vec (nargs);
7945 if (unify (tparms, tempargs, parm, arg, sub_strict) != 0)
7948 /* First make sure we didn't deduce anything that conflicts with
7949 explicitly specified args. */
7950 for (i = nargs; i--; )
7952 tree elt = TREE_VEC_ELT (tempargs, i);
7953 tree oldelt = TREE_VEC_ELT (orig_targs, i);
7955 if (elt == NULL_TREE)
7957 else if (uses_template_parms (elt))
7959 /* Since we're unifying against ourselves, we will fill in template
7960 args used in the function parm list with our own template parms.
7962 TREE_VEC_ELT (tempargs, i) = NULL_TREE;
7965 else if (oldelt && ! template_args_equal (oldelt, elt))
7969 for (i = nargs; i--; )
7971 tree elt = TREE_VEC_ELT (tempargs, i);
7974 TREE_VEC_ELT (targs, i) = elt;
7980 /* PARM is a template class (perhaps with unbound template
7981 parameters). ARG is a fully instantiated type. If ARG can be
7982 bound to PARM, return ARG, otherwise return NULL_TREE. TPARMS and
7983 TARGS are as for unify. */
7986 try_class_unification (tparms, targs, parm, arg)
7995 if (!CLASSTYPE_TEMPLATE_INFO (arg)
7996 || CLASSTYPE_TI_TEMPLATE (arg) != CLASSTYPE_TI_TEMPLATE (parm))
7999 /* We need to make a new template argument vector for the call to
8000 unify. If we used TARGS, we'd clutter it up with the result of
8001 the attempted unification, even if this class didn't work out.
8002 We also don't want to commit ourselves to all the unifications
8003 we've already done, since unification is supposed to be done on
8004 an argument-by-argument basis. In other words, consider the
8005 following pathological case:
8007 template <int I, int J, int K>
8010 template <int I, int J>
8011 struct S<I, J, 2> : public S<I, I, I>, S<J, J, J> {};
8013 template <int I, int J, int K>
8014 void f(S<I, J, K>, S<I, I, I>);
8023 Now, by the time we consider the unification involving `s2', we
8024 already know that we must have `f<0, 0, 0>'. But, even though
8025 `S<0, 1, 2>' is derived from `S<0, 0, 0>', the code is not legal
8026 because there are two ways to unify base classes of S<0, 1, 2>
8027 with S<I, I, I>. If we kept the already deduced knowledge, we
8028 would reject the possibility I=1. */
8029 copy_of_targs = make_tree_vec (TREE_VEC_LENGTH (targs));
8030 i = unify (tparms, copy_of_targs, CLASSTYPE_TI_ARGS (parm),
8031 CLASSTYPE_TI_ARGS (arg), UNIFY_ALLOW_NONE);
8033 /* If unification failed, we're done. */
8040 /* Subroutine of get_template_base. RVAL, if non-NULL, is a base we
8041 have alreay discovered to be satisfactory. ARG_BINFO is the binfo
8042 for the base class of ARG that we are currently examining. */
8045 get_template_base_recursive (tparms, targs, parm,
8046 arg_binfo, rval, flags)
8056 tree arg = BINFO_TYPE (arg_binfo);
8058 if (!(flags & GTB_IGNORE_TYPE))
8060 tree r = try_class_unification (tparms, targs,
8063 /* If there is more than one satisfactory baseclass, then:
8067 If they yield more than one possible deduced A, the type
8071 if (r && rval && !same_type_p (r, rval))
8072 return error_mark_node;
8077 binfos = BINFO_BASETYPES (arg_binfo);
8078 n_baselinks = binfos ? TREE_VEC_LENGTH (binfos) : 0;
8080 /* Process base types. */
8081 for (i = 0; i < n_baselinks; i++)
8083 tree base_binfo = TREE_VEC_ELT (binfos, i);
8086 /* Skip this base, if we've already seen it. */
8087 if (BINFO_MARKED (base_binfo))
8091 (flags & GTB_VIA_VIRTUAL) || TREE_VIA_VIRTUAL (base_binfo);
8093 /* When searching for a non-virtual, we cannot mark virtually
8096 SET_BINFO_MARKED (base_binfo);
8098 rval = get_template_base_recursive (tparms, targs,
8102 GTB_VIA_VIRTUAL * this_virtual);
8104 /* If we discovered more than one matching base class, we can
8106 if (rval == error_mark_node)
8107 return error_mark_node;
8113 /* Given a template type PARM and a class type ARG, find the unique
8114 base type in ARG that is an instance of PARM. We do not examine
8115 ARG itself; only its base-classes. If there is no appropriate base
8116 class, return NULL_TREE. If there is more than one, return
8117 error_mark_node. PARM may be the type of a partial specialization,
8118 as well as a plain template type. Used by unify. */
8121 get_template_base (tparms, targs, parm, arg)
8130 my_friendly_assert (IS_AGGR_TYPE_CODE (TREE_CODE (arg)), 92);
8132 arg_binfo = TYPE_BINFO (complete_type (arg));
8133 rval = get_template_base_recursive (tparms, targs,
8138 /* Since get_template_base_recursive marks the bases classes, we
8139 must unmark them here. */
8140 dfs_walk (arg_binfo, dfs_unmark, markedp, 0);
8145 /* Returns the level of DECL, which declares a template parameter. */
8148 template_decl_level (decl)
8151 switch (TREE_CODE (decl))
8155 return TEMPLATE_TYPE_LEVEL (TREE_TYPE (decl));
8158 return TEMPLATE_PARM_LEVEL (DECL_INITIAL (decl));
8161 my_friendly_abort (0);
8166 /* Decide whether ARG can be unified with PARM, considering only the
8167 cv-qualifiers of each type, given STRICT as documented for unify.
8168 Returns non-zero iff the unification is OK on that basis.*/
8171 check_cv_quals_for_unify (strict, arg, parm)
8176 if (!(strict & UNIFY_ALLOW_MORE_CV_QUAL)
8177 && !at_least_as_qualified_p (arg, parm))
8180 if (!(strict & UNIFY_ALLOW_LESS_CV_QUAL)
8181 && !at_least_as_qualified_p (parm, arg))
8187 /* Takes parameters as for type_unification. Returns 0 if the
8188 type deduction suceeds, 1 otherwise. The parameter STRICT is a
8189 bitwise or of the following flags:
8192 Require an exact match between PARM and ARG.
8193 UNIFY_ALLOW_MORE_CV_QUAL:
8194 Allow the deduced ARG to be more cv-qualified than ARG.
8195 UNIFY_ALLOW_LESS_CV_QUAL:
8196 Allow the deduced ARG to be less cv-qualified than ARG.
8197 UNIFY_ALLOW_DERIVED:
8198 Allow the deduced ARG to be a template base class of ARG,
8199 or a pointer to a template base class of the type pointed to by
8201 UNIFY_ALLOW_INTEGER:
8202 Allow any integral type to be deduced. See the TEMPLATE_PARM_INDEX
8203 case for more information. */
8206 unify (tparms, targs, parm, arg, strict)
8207 tree tparms, targs, parm, arg;
8214 /* I don't think this will do the right thing with respect to types.
8215 But the only case I've seen it in so far has been array bounds, where
8216 signedness is the only information lost, and I think that will be
8218 while (TREE_CODE (parm) == NOP_EXPR)
8219 parm = TREE_OPERAND (parm, 0);
8221 if (arg == error_mark_node)
8223 if (arg == unknown_type_node)
8224 /* We can't deduce anything from this, but we might get all the
8225 template args from other function args. */
8228 /* If PARM uses template parameters, then we can't bail out here,
8229 even if ARG == PARM, since we won't record unifications for the
8230 template parameters. We might need them if we're trying to
8231 figure out which of two things is more specialized. */
8232 if (arg == parm && !uses_template_parms (parm))
8235 /* Immediately reject some pairs that won't unify because of
8236 cv-qualification mismatches. */
8237 if (TREE_CODE (arg) == TREE_CODE (parm)
8238 && TREE_CODE_CLASS (TREE_CODE (arg)) == 't'
8239 /* We check the cv-qualifiers when unifying with template type
8240 parameters below. We want to allow ARG `const T' to unify with
8241 PARM `T' for example, when computing which of two templates
8242 is more specialized, for example. */
8243 && TREE_CODE (arg) != TEMPLATE_TYPE_PARM
8244 && !check_cv_quals_for_unify (strict, arg, parm))
8247 switch (TREE_CODE (parm))
8250 /* In a type which contains a nested-name-specifier, template
8251 argument values cannot be deduced for template parameters used
8252 within the nested-name-specifier. */
8255 case TEMPLATE_TYPE_PARM:
8256 case TEMPLATE_TEMPLATE_PARM:
8257 tparm = TREE_VALUE (TREE_VEC_ELT (tparms, 0));
8259 if (TEMPLATE_TYPE_LEVEL (parm)
8260 != template_decl_level (tparm))
8261 /* The PARM is not one we're trying to unify. Just check
8262 to see if it matches ARG. */
8263 return (TREE_CODE (arg) == TREE_CODE (parm)
8264 && same_type_p (parm, arg)) ? 0 : 1;
8265 idx = TEMPLATE_TYPE_IDX (parm);
8266 targ = TREE_VEC_ELT (targs, idx);
8267 tparm = TREE_VALUE (TREE_VEC_ELT (tparms, idx));
8269 /* Check for mixed types and values. */
8270 if ((TREE_CODE (parm) == TEMPLATE_TYPE_PARM
8271 && TREE_CODE (tparm) != TYPE_DECL)
8272 || (TREE_CODE (parm) == TEMPLATE_TEMPLATE_PARM
8273 && TREE_CODE (tparm) != TEMPLATE_DECL))
8276 if (TREE_CODE (parm) == TEMPLATE_TEMPLATE_PARM)
8278 if (TEMPLATE_TEMPLATE_PARM_TEMPLATE_INFO (parm))
8280 /* We arrive here when PARM does not involve template
8283 /* ARG must be constructed from a template class. */
8284 if (TREE_CODE (arg) != RECORD_TYPE || !CLASSTYPE_TEMPLATE_INFO (arg))
8288 tree parmtmpl = TYPE_TI_TEMPLATE (parm);
8289 tree parmvec = TYPE_TI_ARGS (parm);
8290 tree argvec = CLASSTYPE_TI_ARGS (arg);
8292 = DECL_INNERMOST_TEMPLATE_PARMS (CLASSTYPE_TI_TEMPLATE (arg));
8295 /* The parameter and argument roles have to be switched here
8296 in order to handle default arguments properly. For example,
8297 template<template <class> class TT> void f(TT<int>)
8298 should be able to accept vector<int> which comes from
8299 template <class T, class Allocator = allocator>
8302 if (coerce_template_parms (argtmplvec, parmvec, parmtmpl, 0, 1)
8306 /* Deduce arguments T, i from TT<T> or TT<i>.
8307 We check each element of PARMVEC and ARGVEC individually
8308 rather than the whole TREE_VEC since they can have
8309 different number of elements. */
8311 for (i = 0; i < TREE_VEC_LENGTH (parmvec); ++i)
8313 tree t = TREE_VEC_ELT (parmvec, i);
8315 if (unify (tparms, targs, t,
8316 TREE_VEC_ELT (argvec, i),
8321 arg = CLASSTYPE_TI_TEMPLATE (arg);
8326 /* If PARM is `const T' and ARG is only `int', we don't have
8327 a match unless we are allowing additional qualification.
8328 If ARG is `const int' and PARM is just `T' that's OK;
8329 that binds `const int' to `T'. */
8330 if (!check_cv_quals_for_unify (strict | UNIFY_ALLOW_LESS_CV_QUAL,
8334 /* Consider the case where ARG is `const volatile int' and
8335 PARM is `const T'. Then, T should be `volatile int'. */
8337 cp_build_qualified_type_real (arg,
8339 & ~CP_TYPE_QUALS (parm),
8341 if (arg == error_mark_node)
8345 /* Simple cases: Value already set, does match or doesn't. */
8346 if (targ != NULL_TREE && same_type_p (targ, arg))
8351 /* Make sure that ARG is not a variable-sized array. (Note that
8352 were talking about variable-sized arrays (like `int[n]'),
8353 rather than arrays of unknown size (like `int[]').) We'll
8354 get very confused by such a type since the bound of the array
8355 will not be computable in an instantiation. Besides, such
8356 types are not allowed in ISO C++, so we can do as we please
8358 if (TREE_CODE (arg) == ARRAY_TYPE
8359 && !uses_template_parms (arg)
8360 && (TREE_CODE (TYPE_MAX_VALUE (TYPE_DOMAIN (arg)))
8364 TREE_VEC_ELT (targs, idx) = arg;
8367 case TEMPLATE_PARM_INDEX:
8368 tparm = TREE_VALUE (TREE_VEC_ELT (tparms, 0));
8370 if (TEMPLATE_PARM_LEVEL (parm)
8371 != template_decl_level (tparm))
8372 /* The PARM is not one we're trying to unify. Just check
8373 to see if it matches ARG. */
8374 return (TREE_CODE (arg) == TREE_CODE (parm)
8375 && cp_tree_equal (parm, arg) > 0) ? 0 : 1;
8377 idx = TEMPLATE_PARM_IDX (parm);
8378 targ = TREE_VEC_ELT (targs, idx);
8382 int i = (cp_tree_equal (targ, arg) > 0);
8388 my_friendly_abort (42);
8391 /* [temp.deduct.type] If, in the declaration of a function template
8392 with a non-type template-parameter, the non-type
8393 template-parameter is used in an expression in the function
8394 parameter-list and, if the corresponding template-argument is
8395 deduced, the template-argument type shall match the type of the
8396 template-parameter exactly, except that a template-argument
8397 deduced from an array bound may be of any integral type. */
8398 if (same_type_p (TREE_TYPE (arg), TREE_TYPE (parm)))
8400 else if ((strict & UNIFY_ALLOW_INTEGER)
8401 && (TREE_CODE (TREE_TYPE (parm)) == INTEGER_TYPE
8402 || TREE_CODE (TREE_TYPE (parm)) == BOOLEAN_TYPE))
8407 TREE_VEC_ELT (targs, idx) = arg;
8414 if (TREE_CODE (arg) != POINTER_TYPE)
8417 /* [temp.deduct.call]
8419 A can be another pointer or pointer to member type that can
8420 be converted to the deduced A via a qualification
8421 conversion (_conv.qual_).
8423 We pass down STRICT here rather than UNIFY_ALLOW_NONE.
8424 This will allow for additional cv-qualification of the
8425 pointed-to types if appropriate. In general, this is a bit
8426 too generous; we are only supposed to allow qualification
8427 conversions and this method will allow an ARG of char** and
8428 a deduced ARG of const char**. However, overload
8429 resolution will subsequently invalidate the candidate, so
8430 this is probably OK. */
8431 sub_strict = strict;
8433 if (TREE_CODE (TREE_TYPE (arg)) != RECORD_TYPE)
8434 /* The derived-to-base conversion only persists through one
8435 level of pointers. */
8436 sub_strict &= ~UNIFY_ALLOW_DERIVED;
8438 return unify (tparms, targs, TREE_TYPE (parm),
8439 TREE_TYPE (arg), sub_strict);
8442 case REFERENCE_TYPE:
8443 if (TREE_CODE (arg) != REFERENCE_TYPE)
8445 return unify (tparms, targs, TREE_TYPE (parm), TREE_TYPE (arg),
8449 if (TREE_CODE (arg) != ARRAY_TYPE)
8451 if ((TYPE_DOMAIN (parm) == NULL_TREE)
8452 != (TYPE_DOMAIN (arg) == NULL_TREE))
8454 if (TYPE_DOMAIN (parm) != NULL_TREE
8455 && unify (tparms, targs, TYPE_DOMAIN (parm),
8456 TYPE_DOMAIN (arg), UNIFY_ALLOW_NONE) != 0)
8458 return unify (tparms, targs, TREE_TYPE (parm), TREE_TYPE (arg),
8466 if (TREE_CODE (arg) != TREE_CODE (parm))
8469 if (TREE_CODE (parm) == INTEGER_TYPE
8470 && TREE_CODE (TYPE_MAX_VALUE (parm)) != INTEGER_CST)
8472 if (TYPE_MIN_VALUE (parm) && TYPE_MIN_VALUE (arg)
8473 && unify (tparms, targs, TYPE_MIN_VALUE (parm),
8474 TYPE_MIN_VALUE (arg), UNIFY_ALLOW_INTEGER))
8476 if (TYPE_MAX_VALUE (parm) && TYPE_MAX_VALUE (arg)
8477 && unify (tparms, targs, TYPE_MAX_VALUE (parm),
8478 TYPE_MAX_VALUE (arg), UNIFY_ALLOW_INTEGER))
8481 /* We use the TYPE_MAIN_VARIANT since we have already
8482 checked cv-qualification at the top of the
8484 else if (!same_type_p (TYPE_MAIN_VARIANT (arg),
8485 TYPE_MAIN_VARIANT (parm)))
8488 /* As far as unification is concerned, this wins. Later checks
8489 will invalidate it if necessary. */
8492 /* Types INTEGER_CST and MINUS_EXPR can come from array bounds. */
8493 /* Type INTEGER_CST can come from ordinary constant template args. */
8495 while (TREE_CODE (arg) == NOP_EXPR)
8496 arg = TREE_OPERAND (arg, 0);
8498 if (TREE_CODE (arg) != INTEGER_CST)
8500 return !tree_int_cst_equal (parm, arg);
8505 if (TREE_CODE (arg) != TREE_VEC)
8507 if (TREE_VEC_LENGTH (parm) != TREE_VEC_LENGTH (arg))
8509 for (i = TREE_VEC_LENGTH (parm) - 1; i >= 0; i--)
8510 if (unify (tparms, targs,
8511 TREE_VEC_ELT (parm, i), TREE_VEC_ELT (arg, i),
8519 if (TREE_CODE (arg) != TREE_CODE (parm))
8522 if (TYPE_PTRMEMFUNC_P (parm))
8524 if (!TYPE_PTRMEMFUNC_P (arg))
8527 return unify (tparms, targs,
8528 TYPE_PTRMEMFUNC_FN_TYPE (parm),
8529 TYPE_PTRMEMFUNC_FN_TYPE (arg),
8533 if (CLASSTYPE_TEMPLATE_INFO (parm))
8537 if (strict & UNIFY_ALLOW_DERIVED)
8539 /* First, we try to unify the PARM and ARG directly. */
8540 t = try_class_unification (tparms, targs,
8545 /* Fallback to the special case allowed in
8548 If P is a class, and P has the form
8549 template-id, then A can be a derived class of
8550 the deduced A. Likewise, if P is a pointer to
8551 a class of the form template-id, A can be a
8552 pointer to a derived class pointed to by the
8554 t = get_template_base (tparms, targs,
8557 if (! t || t == error_mark_node)
8561 else if (CLASSTYPE_TEMPLATE_INFO (arg)
8562 && (CLASSTYPE_TI_TEMPLATE (parm)
8563 == CLASSTYPE_TI_TEMPLATE (arg)))
8564 /* Perhaps PARM is something like S<U> and ARG is S<int>.
8565 Then, we should unify `int' and `U'. */
8568 /* There's no chance of unication succeeding. */
8571 return unify (tparms, targs, CLASSTYPE_TI_ARGS (parm),
8572 CLASSTYPE_TI_ARGS (t), UNIFY_ALLOW_NONE);
8574 else if (!same_type_p (TYPE_MAIN_VARIANT (parm),
8575 TYPE_MAIN_VARIANT (arg)))
8581 if (TREE_CODE (arg) != TREE_CODE (parm))
8584 if (unify (tparms, targs, TREE_TYPE (parm),
8585 TREE_TYPE (arg), UNIFY_ALLOW_NONE))
8587 return type_unification_real (tparms, targs, TYPE_ARG_TYPES (parm),
8588 TYPE_ARG_TYPES (arg), 1,
8592 if (TREE_CODE (arg) != OFFSET_TYPE)
8594 if (unify (tparms, targs, TYPE_OFFSET_BASETYPE (parm),
8595 TYPE_OFFSET_BASETYPE (arg), UNIFY_ALLOW_NONE))
8597 return unify (tparms, targs, TREE_TYPE (parm), TREE_TYPE (arg),
8601 if (arg != decl_constant_value (parm))
8606 /* Matched cases are handled by the ARG == PARM test above. */
8610 if (TREE_CODE (TREE_OPERAND (parm, 1)) == INTEGER_CST)
8612 /* We handle this case specially, since it comes up with
8613 arrays. In particular, something like:
8615 template <int N> void f(int (&x)[N]);
8617 Here, we are trying to unify the range type, which
8618 looks like [0 ... (N - 1)]. */
8620 t1 = TREE_OPERAND (parm, 0);
8621 t2 = TREE_OPERAND (parm, 1);
8623 t = fold (build (PLUS_EXPR, integer_type_node, arg, t2));
8625 return unify (tparms, targs, t1, t, strict);
8627 /* else fall through */
8630 if (IS_EXPR_CODE_CLASS (TREE_CODE_CLASS (TREE_CODE (parm))))
8631 /* We're looking at an expression. This can happen with
8635 void foo(S<I>, S<I + 2>);
8637 This is a "nondeduced context":
8641 The nondeduced contexts are:
8643 --A type that is a template-id in which one or more of
8644 the template-arguments is an expression that references
8645 a template-parameter.
8647 In these cases, we assume deduction succeeded, but don't
8648 actually infer any unifications. */
8651 sorry ("use of `%s' in template type unification",
8652 tree_code_name [(int) TREE_CODE (parm)]);
8658 /* Called if RESULT is explicitly instantiated, or is a member of an
8659 explicitly instantiated class, or if using -frepo and the
8660 instantiation of RESULT has been assigned to this file. */
8663 mark_decl_instantiated (result, extern_p)
8667 if (TREE_CODE (result) != FUNCTION_DECL)
8668 /* The TREE_PUBLIC flag for function declarations will have been
8669 set correctly by tsubst. */
8670 TREE_PUBLIC (result) = 1;
8674 DECL_INTERFACE_KNOWN (result) = 1;
8675 DECL_NOT_REALLY_EXTERN (result) = 1;
8677 /* Always make artificials weak. */
8678 if (DECL_ARTIFICIAL (result) && flag_weak)
8679 comdat_linkage (result);
8680 /* For WIN32 we also want to put explicit instantiations in
8681 linkonce sections. */
8682 else if (TREE_PUBLIC (result))
8683 maybe_make_one_only (result);
8685 else if (TREE_CODE (result) == FUNCTION_DECL)
8686 mark_inline_for_output (result);
8689 /* Given two function templates PAT1 and PAT2, and explicit template
8690 arguments EXPLICIT_ARGS return:
8692 1 if PAT1 is more specialized than PAT2 as described in [temp.func.order].
8693 -1 if PAT2 is more specialized than PAT1.
8694 0 if neither is more specialized. */
8697 more_specialized (pat1, pat2, explicit_args)
8698 tree pat1, pat2, explicit_args;
8703 targs = get_bindings_overload (pat1, DECL_RESULT (pat2), explicit_args);
8707 targs = get_bindings_overload (pat2, DECL_RESULT (pat1), explicit_args);
8714 /* Given two class template specialization list nodes PAT1 and PAT2, return:
8716 1 if PAT1 is more specialized than PAT2 as described in [temp.class.order].
8717 -1 if PAT2 is more specialized than PAT1.
8718 0 if neither is more specialized. */
8721 more_specialized_class (pat1, pat2)
8727 targs = get_class_bindings (TREE_VALUE (pat1), TREE_PURPOSE (pat1),
8728 TREE_PURPOSE (pat2));
8732 targs = get_class_bindings (TREE_VALUE (pat2), TREE_PURPOSE (pat2),
8733 TREE_PURPOSE (pat1));
8740 /* Return the template arguments that will produce the function signature
8741 DECL from the function template FN, with the explicit template
8742 arguments EXPLICIT_ARGS. If CHECK_RETTYPE is 1, the return type must
8743 also match. Return NULL_TREE if no satisfactory arguments could be
8747 get_bindings_real (fn, decl, explicit_args, check_rettype)
8748 tree fn, decl, explicit_args;
8751 int ntparms = DECL_NTPARMS (fn);
8752 tree targs = make_tree_vec (ntparms);
8754 tree decl_arg_types;
8757 /* Substitute the explicit template arguments into the type of DECL.
8758 The call to fn_type_unification will handle substitution into the
8760 decl_type = TREE_TYPE (decl);
8761 if (explicit_args && uses_template_parms (decl_type))
8764 tree converted_args;
8766 if (DECL_TEMPLATE_INFO (decl))
8767 tmpl = DECL_TI_TEMPLATE (decl);
8769 /* We can get here for some illegal specializations. */
8773 = (coerce_template_parms (DECL_INNERMOST_TEMPLATE_PARMS (tmpl),
8774 explicit_args, NULL_TREE,
8776 /*require_all_arguments=*/0));
8777 if (converted_args == error_mark_node)
8780 decl_type = tsubst (decl_type, converted_args, /*complain=*/0,
8782 if (decl_type == error_mark_node)
8786 /* If FN is a static member function, adjust the type of DECL
8788 decl_arg_types = TYPE_ARG_TYPES (decl_type);
8789 if (DECL_STATIC_FUNCTION_P (fn)
8790 && DECL_NONSTATIC_MEMBER_FUNCTION_P (decl))
8791 decl_arg_types = TREE_CHAIN (decl_arg_types);
8793 i = fn_type_unification (fn, explicit_args, targs,
8795 TREE_TYPE (decl_type),
8803 /* Check to see that the resulting return type is also OK. */
8804 tree t = tsubst (TREE_TYPE (TREE_TYPE (fn)), targs,
8805 /*complain=*/0, NULL_TREE);
8807 if (!same_type_p (t, TREE_TYPE (TREE_TYPE (decl))))
8814 /* For most uses, we want to check the return type. */
8817 get_bindings (fn, decl, explicit_args)
8818 tree fn, decl, explicit_args;
8820 return get_bindings_real (fn, decl, explicit_args, 1);
8823 /* But for more_specialized, we only care about the parameter types. */
8826 get_bindings_overload (fn, decl, explicit_args)
8827 tree fn, decl, explicit_args;
8829 return get_bindings_real (fn, decl, explicit_args, 0);
8832 /* Return the innermost template arguments that, when applied to a
8833 template specialization whose innermost template parameters are
8834 TPARMS, and whose specialization arguments are ARGS, yield the
8837 For example, suppose we have:
8839 template <class T, class U> struct S {};
8840 template <class T> struct S<T*, int> {};
8842 Then, suppose we want to get `S<double*, int>'. The TPARMS will be
8843 {T}, the PARMS will be {T*, int} and the ARGS will be {double*,
8844 int}. The resulting vector will be {double}, indicating that `T'
8845 is bound to `double'. */
8848 get_class_bindings (tparms, parms, args)
8849 tree tparms, parms, args;
8851 int i, ntparms = TREE_VEC_LENGTH (tparms);
8852 tree vec = make_tree_vec (ntparms);
8854 args = innermost_args (args);
8856 if (unify (tparms, vec, parms, args, UNIFY_ALLOW_NONE))
8859 for (i = 0; i < ntparms; ++i)
8860 if (! TREE_VEC_ELT (vec, i))
8866 /* In INSTANTIATIONS is a list of <INSTANTIATION, TEMPLATE> pairs.
8867 Pick the most specialized template, and return the corresponding
8868 instantiation, or if there is no corresponding instantiation, the
8869 template itself. EXPLICIT_ARGS is any template arguments explicity
8870 mentioned in a template-id. If there is no most specialized
8871 tempalte, error_mark_node is returned. If there are no templates
8872 at all, NULL_TREE is returned. */
8875 most_specialized_instantiation (instantiations, explicit_args)
8876 tree instantiations;
8882 if (!instantiations)
8885 champ = instantiations;
8886 for (fn = TREE_CHAIN (instantiations); fn; fn = TREE_CHAIN (fn))
8888 fate = more_specialized (TREE_VALUE (champ),
8889 TREE_VALUE (fn), explicit_args);
8896 fn = TREE_CHAIN (fn);
8898 return error_mark_node;
8904 for (fn = instantiations; fn && fn != champ; fn = TREE_CHAIN (fn))
8906 fate = more_specialized (TREE_VALUE (champ),
8907 TREE_VALUE (fn), explicit_args);
8909 return error_mark_node;
8912 return TREE_PURPOSE (champ) ? TREE_PURPOSE (champ) : TREE_VALUE (champ);
8915 /* Return the most specialized of the list of templates in FNS that can
8916 produce an instantiation matching DECL, given the explicit template
8917 arguments EXPLICIT_ARGS. */
8920 most_specialized (fns, decl, explicit_args)
8921 tree fns, decl, explicit_args;
8923 tree candidates = NULL_TREE;
8926 for (fn = fns; fn; fn = TREE_CHAIN (fn))
8928 tree candidate = TREE_VALUE (fn);
8930 args = get_bindings (candidate, decl, explicit_args);
8932 candidates = tree_cons (NULL_TREE, candidate, candidates);
8935 return most_specialized_instantiation (candidates, explicit_args);
8938 /* If DECL is a specialization of some template, return the most
8939 general such template. For example, given:
8941 template <class T> struct S { template <class U> void f(U); };
8943 if TMPL is `template <class U> void S<int>::f(U)' this will return
8944 the full template. This function will not trace past partial
8945 specializations, however. For example, given in addition:
8947 template <class T> struct S<T*> { template <class U> void f(U); };
8949 if TMPL is `template <class U> void S<int*>::f(U)' this will return
8950 `template <class T> template <class U> S<T*>::f(U)'. */
8953 most_general_template (decl)
8956 while (DECL_TEMPLATE_INFO (decl)
8957 /* The DECL_TI_TEMPLATE can be a LOOKUP_EXPR or
8958 IDENTIFIER_NODE in some cases. (See cp-tree.h for
8960 && TREE_CODE (DECL_TI_TEMPLATE (decl)) == TEMPLATE_DECL)
8961 decl = DECL_TI_TEMPLATE (decl);
8966 /* Return the most specialized of the class template specializations
8967 of TMPL which can produce an instantiation matching ARGS, or
8968 error_mark_node if the choice is ambiguous. */
8971 most_specialized_class (tmpl, args)
8975 tree list = NULL_TREE;
8980 tmpl = most_general_template (tmpl);
8981 for (t = DECL_TEMPLATE_SPECIALIZATIONS (tmpl); t; t = TREE_CHAIN (t))
8984 = get_class_bindings (TREE_VALUE (t), TREE_PURPOSE (t), args);
8987 list = decl_tree_cons (TREE_PURPOSE (t), TREE_VALUE (t), list);
8988 TREE_TYPE (list) = TREE_TYPE (t);
8998 for (; t; t = TREE_CHAIN (t))
9000 fate = more_specialized_class (champ, t);
9009 return error_mark_node;
9015 for (t = list; t && t != champ; t = TREE_CHAIN (t))
9017 fate = more_specialized_class (champ, t);
9019 return error_mark_node;
9025 /* called from the parser. */
9028 do_decl_instantiation (declspecs, declarator, storage)
9029 tree declspecs, declarator, storage;
9031 tree decl = grokdeclarator (declarator, declspecs, NORMAL, 0, NULL_TREE);
9032 tree result = NULL_TREE;
9036 /* An error ocurred, for which grokdeclarator has already issued
9037 an appropriate message. */
9039 else if (! DECL_LANG_SPECIFIC (decl))
9041 cp_error ("explicit instantiation of non-template `%#D'", decl);
9044 else if (TREE_CODE (decl) == VAR_DECL)
9046 /* There is an asymmetry here in the way VAR_DECLs and
9047 FUNCTION_DECLs are handled by grokdeclarator. In the case of
9048 the latter, the DECL we get back will be marked as a
9049 template instantiation, and the appropriate
9050 DECL_TEMPLATE_INFO will be set up. This does not happen for
9051 VAR_DECLs so we do the lookup here. Probably, grokdeclarator
9052 should handle VAR_DECLs as it currently handles
9054 result = lookup_field (DECL_CONTEXT (decl), DECL_NAME (decl), 0, 0);
9055 if (result && TREE_CODE (result) != VAR_DECL)
9057 cp_error ("no matching template for `%D' found", result);
9061 else if (TREE_CODE (decl) != FUNCTION_DECL)
9063 cp_error ("explicit instantiation of `%#D'", decl);
9069 /* Check for various error cases. Note that if the explicit
9070 instantiation is legal the RESULT will currently be marked as an
9071 *implicit* instantiation; DECL_EXPLICIT_INSTANTIATION is not set
9072 until we get here. */
9074 if (DECL_TEMPLATE_SPECIALIZATION (result))
9078 No program shall both explicitly instantiate and explicitly
9079 specialize a template. */
9080 cp_pedwarn ("explicit instantiation of `%#D' after", result);
9081 cp_pedwarn_at ("explicit specialization here", result);
9084 else if (DECL_EXPLICIT_INSTANTIATION (result))
9088 No program shall explicitly instantiate any template more
9091 We check DECL_INTERFACE_KNOWN so as not to complain when the first
9092 instantiation was `extern' and the second is not, and EXTERN_P for
9093 the opposite case. If -frepo, chances are we already got marked
9094 as an explicit instantion because of the repo file. */
9095 if (DECL_INTERFACE_KNOWN (result) && !extern_p && !flag_use_repository)
9096 cp_pedwarn ("duplicate explicit instantiation of `%#D'", result);
9098 /* If we've already instantiated the template, just return now. */
9099 if (DECL_INTERFACE_KNOWN (result))
9102 else if (!DECL_IMPLICIT_INSTANTIATION (result))
9104 cp_error ("no matching template for `%D' found", result);
9107 else if (!DECL_TEMPLATE_INFO (result))
9109 cp_pedwarn ("explicit instantiation of non-template `%#D'", result);
9113 if (flag_external_templates)
9116 if (storage == NULL_TREE)
9118 else if (storage == ridpointers[(int) RID_EXTERN])
9121 cp_pedwarn ("ANSI C++ forbids the use of `extern' on explicit instantiations");
9125 cp_error ("storage class `%D' applied to template instantiation",
9128 SET_DECL_EXPLICIT_INSTANTIATION (result);
9129 mark_decl_instantiated (result, extern_p);
9130 repo_template_instantiated (result, extern_p);
9132 instantiate_decl (result);
9136 mark_class_instantiated (t, extern_p)
9140 SET_CLASSTYPE_EXPLICIT_INSTANTIATION (t);
9141 SET_CLASSTYPE_INTERFACE_KNOWN (t);
9142 CLASSTYPE_INTERFACE_ONLY (t) = extern_p;
9143 CLASSTYPE_VTABLE_NEEDS_WRITING (t) = ! extern_p;
9144 TYPE_DECL_SUPPRESS_DEBUG (TYPE_NAME (t)) = extern_p;
9147 CLASSTYPE_DEBUG_REQUESTED (t) = 1;
9148 rest_of_type_compilation (t, 1);
9153 do_type_instantiation (t, storage)
9160 if (TREE_CODE (t) == TYPE_DECL)
9163 if (! CLASS_TYPE_P (t) || ! CLASSTYPE_TEMPLATE_INFO (t))
9165 cp_error ("explicit instantiation of non-template type `%T'", t);
9171 /* With -fexternal-templates, explicit instantiations are treated the same
9172 as implicit ones. */
9173 if (flag_external_templates)
9176 if (TYPE_SIZE (t) == NULL_TREE)
9178 cp_error ("explicit instantiation of `%#T' before definition of template",
9183 if (storage != NULL_TREE)
9186 cp_pedwarn("ANSI C++ forbids the use of `%s' on explicit instantiations",
9187 IDENTIFIER_POINTER (storage));
9189 if (storage == ridpointers[(int) RID_INLINE])
9191 else if (storage == ridpointers[(int) RID_EXTERN])
9193 else if (storage == ridpointers[(int) RID_STATIC])
9197 cp_error ("storage class `%D' applied to template instantiation",
9203 if (CLASSTYPE_TEMPLATE_SPECIALIZATION (t))
9207 No program shall both explicitly instantiate and explicitly
9208 specialize a template. */
9209 cp_error ("explicit instantiation of `%#T' after", t);
9210 cp_error_at ("explicit specialization here", t);
9213 else if (CLASSTYPE_EXPLICIT_INSTANTIATION (t))
9217 No program shall explicitly instantiate any template more
9220 If CLASSTYPE_INTERFACE_ONLY, then the first explicit instantiation
9221 was `extern'. If EXTERN_P then the second is. If -frepo, chances
9222 are we already got marked as an explicit instantion because of the
9223 repo file. All these cases are OK. */
9224 if (!CLASSTYPE_INTERFACE_ONLY (t) && !extern_p && !flag_use_repository)
9225 cp_pedwarn ("duplicate explicit instantiation of `%#T'", t);
9227 /* If we've already instantiated the template, just return now. */
9228 if (!CLASSTYPE_INTERFACE_ONLY (t))
9232 mark_class_instantiated (t, extern_p);
9233 repo_template_instantiated (t, extern_p);
9241 /* In contrast to implicit instantiation, where only the
9242 declarations, and not the definitions, of members are
9243 instantiated, we have here:
9247 The explicit instantiation of a class template specialization
9248 implies the instantiation of all of its members not
9249 previously explicitly specialized in the translation unit
9250 containing the explicit instantiation.
9252 Of course, we can't instantiate member template classes, since
9253 we don't have any arguments for them. Note that the standard
9254 is unclear on whether the instatiation of the members are
9255 *explicit* instantiations or not. We choose to be generous,
9256 and not set DECL_EXPLICIT_INSTANTIATION. Therefore, we allow
9257 the explicit instantiation of a class where some of the members
9258 have no definition in the current translation unit. */
9261 for (tmp = TYPE_METHODS (t); tmp; tmp = TREE_CHAIN (tmp))
9262 if (TREE_CODE (tmp) == FUNCTION_DECL
9263 && DECL_TEMPLATE_INSTANTIATION (tmp))
9265 mark_decl_instantiated (tmp, extern_p);
9266 repo_template_instantiated (tmp, extern_p);
9268 instantiate_decl (tmp);
9271 for (tmp = TYPE_FIELDS (t); tmp; tmp = TREE_CHAIN (tmp))
9272 if (TREE_CODE (tmp) == VAR_DECL && DECL_TEMPLATE_INSTANTIATION (tmp))
9274 mark_decl_instantiated (tmp, extern_p);
9275 repo_template_instantiated (tmp, extern_p);
9277 instantiate_decl (tmp);
9280 for (tmp = CLASSTYPE_TAGS (t); tmp; tmp = TREE_CHAIN (tmp))
9281 if (IS_AGGR_TYPE (TREE_VALUE (tmp))
9282 && !uses_template_parms (CLASSTYPE_TI_ARGS (TREE_VALUE (tmp))))
9283 do_type_instantiation (TYPE_MAIN_DECL (TREE_VALUE (tmp)), storage);
9287 /* Given a function DECL, which is a specialization of TMPL, modify
9288 DECL to be a re-instantiation of TMPL with the same template
9289 arguments. TMPL should be the template into which tsubst'ing
9290 should occur for DECL, not the most general template.
9292 One reason for doing this is a scenario like this:
9295 void f(const T&, int i);
9297 void g() { f(3, 7); }
9300 void f(const T& t, const int i) { }
9302 Note that when the template is first instantiated, with
9303 instantiate_template, the resulting DECL will have no name for the
9304 first parameter, and the wrong type for the second. So, when we go
9305 to instantiate the DECL, we regenerate it. */
9308 regenerate_decl_from_template (decl, tmpl)
9318 args = DECL_TI_ARGS (decl);
9319 code_pattern = DECL_TEMPLATE_RESULT (tmpl);
9321 /* Unregister the specialization so that when we tsubst we will not
9322 just return DECL. We don't have to unregister DECL from TMPL
9323 because if would only be registered there if it were a partial
9324 instantiation of a specialization, which it isn't: it's a full
9326 gen_tmpl = most_general_template (tmpl);
9327 unregistered = unregister_specialization (decl, gen_tmpl);
9329 /* If the DECL was not unregistered then something peculiar is
9330 happening: we created a specialization but did not call
9331 register_specialization for it. */
9332 my_friendly_assert (unregistered, 0);
9334 if (TREE_CODE (decl) == VAR_DECL)
9335 /* Make sure that we can see identifiers, and compute access
9336 correctly, for the class members used in the declaration of
9337 this static variable. */
9338 pushclass (DECL_CONTEXT (decl), 2);
9340 /* Do the substitution to get the new declaration. */
9341 new_decl = tsubst (code_pattern, args, /*complain=*/1, NULL_TREE);
9343 if (TREE_CODE (decl) == VAR_DECL)
9345 /* Set up DECL_INITIAL, since tsubst doesn't. */
9346 DECL_INITIAL (new_decl) =
9347 tsubst_expr (DECL_INITIAL (code_pattern), args,
9348 /*complain=*/1, DECL_TI_TEMPLATE (decl));
9349 /* Pop the class context we pushed above. */
9352 else if (TREE_CODE (decl) == FUNCTION_DECL)
9354 /* Convince duplicate_decls to use the DECL_ARGUMENTS from the
9356 DECL_INITIAL (new_decl) = error_mark_node;
9357 /* And don't complain about a duplicate definition. */
9358 DECL_INITIAL (decl) = NULL_TREE;
9361 /* The immediate parent of the new template is still whatever it was
9362 before, even though tsubst sets DECL_TI_TEMPLATE up as the most
9363 general template. We also reset the DECL_ASSEMBLER_NAME since
9364 tsubst always calculates the name as if the function in question
9365 were really a template instance, and sometimes, with friend
9366 functions, this is not so. See tsubst_friend_function for
9368 DECL_TI_TEMPLATE (new_decl) = DECL_TI_TEMPLATE (decl);
9369 DECL_ASSEMBLER_NAME (new_decl) = DECL_ASSEMBLER_NAME (decl);
9370 DECL_RTL (new_decl) = DECL_RTL (decl);
9372 /* Call duplicate decls to merge the old and new declarations. */
9373 duplicate_decls (new_decl, decl);
9375 /* Now, re-register the specialization. */
9376 register_specialization (decl, gen_tmpl, args);
9379 /* Produce the definition of D, a _DECL generated from a template. */
9382 instantiate_decl (d)
9385 tree tmpl = DECL_TI_TEMPLATE (d);
9386 tree args = DECL_TI_ARGS (d);
9391 int nested = in_function_p ();
9392 int pattern_defined;
9394 char *file = input_filename;
9395 tree old_fn = current_function_decl;
9397 /* This function should only be used to instantiate templates for
9398 functions and static member variables. */
9399 my_friendly_assert (TREE_CODE (d) == FUNCTION_DECL
9400 || TREE_CODE (d) == VAR_DECL, 0);
9402 if (DECL_TEMPLATE_INSTANTIATED (d))
9403 /* D has already been instantiated. It might seem reasonable to
9404 check whether or not D is an explict instantiation, and, if so,
9405 stop here. But when an explicit instantiation is deferred
9406 until the end of the compilation, DECL_EXPLICIT_INSTANTIATION
9407 is set, even though we still need to do the instantiation. */
9410 /* If we already have a specialization of this declaration, then
9411 there's no reason to instantiate it. Note that
9412 retrieve_specialization gives us both instantiations and
9413 specializations, so we must explicitly check
9414 DECL_TEMPLATE_SPECIALIZATION. */
9415 gen_tmpl = most_general_template (tmpl);
9416 spec = retrieve_specialization (gen_tmpl, args);
9417 if (spec != NULL_TREE && DECL_TEMPLATE_SPECIALIZATION (spec))
9420 /* This needs to happen before any tsubsting. */
9421 if (! push_tinst_level (d))
9424 /* Set TD to the template whose DECL_TEMPLATE_RESULT is the pattern
9425 for the instantiation. This is not always the most general
9426 template. Consider, for example:
9429 struct S { template <class U> void f();
9430 template <> void f<int>(); };
9432 and an instantiation of S<double>::f<int>. We want TD to be the
9433 specialization S<T>::f<int>, not the more general S<T>::f<U>. */
9436 /* An instantiation cannot have a definition, so we need a
9437 more general template. */
9438 DECL_TEMPLATE_INSTANTIATION (td)
9439 /* We must also deal with friend templates. Given:
9441 template <class T> struct S {
9442 template <class U> friend void f() {};
9445 S<int>::f<U> say, is not an instantiation of S<T>::f<U>,
9446 so far as the language is concerned, but that's still
9447 where we get the pattern for the instantiation from. On
9448 ther hand, if the definition comes outside the class, say:
9450 template <class T> struct S {
9451 template <class U> friend void f();
9453 template <class U> friend void f() {}
9455 we don't need to look any further. That's what the check for
9456 DECL_INITIAL is for. */
9457 || (TREE_CODE (d) == FUNCTION_DECL
9458 && DECL_FRIEND_PSEUDO_TEMPLATE_INSTANTIATION (td)
9459 && !DECL_INITIAL (DECL_TEMPLATE_RESULT (td)));
9462 /* The present template, TD, should not be a definition. If it
9463 were a definition, we should be using it! Note that we
9464 cannot restructure the loop to just keep going until we find
9465 a template with a definition, since that might go too far if
9466 a specialization was declared, but not defined. */
9467 my_friendly_assert (!(TREE_CODE (d) == VAR_DECL
9468 && !DECL_IN_AGGR_P (DECL_TEMPLATE_RESULT (td))),
9471 /* Fetch the more general template. */
9472 td = DECL_TI_TEMPLATE (td);
9475 code_pattern = DECL_TEMPLATE_RESULT (td);
9477 if (TREE_CODE (d) == FUNCTION_DECL)
9478 pattern_defined = (DECL_SAVED_TREE (code_pattern) != NULL_TREE);
9480 pattern_defined = ! DECL_IN_AGGR_P (code_pattern);
9482 push_to_top_level ();
9483 lineno = DECL_SOURCE_LINE (d);
9484 input_filename = DECL_SOURCE_FILE (d);
9486 if (pattern_defined)
9488 repo_template_used (d);
9490 if (flag_external_templates && ! DECL_INTERFACE_KNOWN (d))
9492 if (flag_alt_external_templates)
9494 if (interface_unknown)
9495 warn_if_unknown_interface (d);
9497 else if (DECL_INTERFACE_KNOWN (code_pattern))
9499 DECL_INTERFACE_KNOWN (d) = 1;
9500 DECL_NOT_REALLY_EXTERN (d) = ! DECL_EXTERNAL (code_pattern);
9503 warn_if_unknown_interface (code_pattern);
9507 import_export_decl (d);
9510 /* Reject all external templates except inline functions. */
9511 if (DECL_INTERFACE_KNOWN (d)
9512 && ! DECL_NOT_REALLY_EXTERN (d)
9513 && ! (TREE_CODE (d) == FUNCTION_DECL && DECL_INLINE (d)))
9516 if (TREE_CODE (d) == VAR_DECL
9517 && TREE_READONLY (d)
9518 && DECL_INITIAL (d) == NULL_TREE
9519 && DECL_INITIAL (code_pattern) != NULL_TREE)
9520 /* We need to set up DECL_INITIAL regardless of pattern_defined if
9521 the variable is a static const initialized in the class body. */;
9522 else if (pattern_defined && nested
9523 && TREE_CODE (d) == FUNCTION_DECL && DECL_INLINE (d))
9524 /* An inline function used in another function; instantiate it now so
9525 we can inline it. */;
9526 else if (! pattern_defined || ! at_eof)
9528 /* Defer all other templates. We restore the source position
9529 here because it's used by add_pending_template. */
9531 input_filename = file;
9533 if (at_eof && !pattern_defined
9534 && DECL_EXPLICIT_INSTANTIATION (d))
9537 The definition of a non-exported function template, a
9538 non-exported member function template, or a non-exported
9539 member function or static data member of a class template
9540 shall be present in every translation unit in which it is
9541 explicitly instantiated. */
9542 cp_error ("explicit instantiation of `%D' but no definition available",
9545 add_pending_template (d);
9549 /* If this instantiation is COMDAT, we don't know whether or not we
9550 will really need to write it out. If we can't be sure, mark it
9551 DECL_DEFER_OUTPUT. NOTE: This increases memory consumption,
9552 since we keep some instantiations in memory rather than write
9553 them out immediately and forget them. A better approach would be
9554 to wait until we know we need them to do the instantiation, but
9555 that would break templates with static locals, because we
9556 generate the functions to destroy statics before we determine
9557 which functions are needed. A better solution would be to
9558 generate the ctor and dtor functions as we go. */
9560 if (TREE_CODE (d) == FUNCTION_DECL
9562 && ! DECL_NEEDED_P (d)
9563 /* If the function that caused us to be instantiated is needed, we
9564 will be needed, too. */
9565 && (! nested || (old_fn && ! DECL_NEEDED_P (old_fn))))
9566 DECL_DEFER_OUTPUT (d) = 1;
9568 /* We're now committed to instantiating this template. Mark it as
9569 instantiated so that recursive calls to instantiate_decl do not
9570 try to instantiate it again. */
9571 DECL_TEMPLATE_INSTANTIATED (d) = 1;
9573 /* Regenerate the declaration in case the template has been modified
9574 by a subsequent redeclaration. */
9575 regenerate_decl_from_template (d, td);
9577 /* We already set the file and line above. Reset them now in case
9578 they changed as a result of calling regenerate_decl_from_template. */
9579 lineno = DECL_SOURCE_LINE (d);
9580 input_filename = DECL_SOURCE_FILE (d);
9582 if (TREE_CODE (d) == VAR_DECL)
9584 DECL_IN_AGGR_P (d) = 0;
9585 if (DECL_INTERFACE_KNOWN (d))
9586 DECL_EXTERNAL (d) = ! DECL_NOT_REALLY_EXTERN (d);
9589 DECL_EXTERNAL (d) = 1;
9590 DECL_NOT_REALLY_EXTERN (d) = 1;
9592 cp_finish_decl (d, DECL_INITIAL (d), NULL_TREE, 0);
9594 else if (TREE_CODE (d) == FUNCTION_DECL)
9596 /* Set up context. */
9597 start_function (NULL_TREE, d, NULL_TREE, SF_PRE_PARSED);
9598 store_parm_decls ();
9600 /* We already set up __FUNCTION__, etc., so we don't want to do
9602 current_function_name_declared = 1;
9604 /* Substitute into the body of the function. */
9605 tsubst_expr (DECL_SAVED_TREE (code_pattern), args,
9606 /*complain=*/1, tmpl);
9608 /* Finish the function. */
9609 expand_body (finish_function (lineno, 0));
9614 input_filename = file;
9616 pop_from_top_level ();
9622 /* Run through the list of templates that we wish we could
9623 instantiate, and instantiate any we can. */
9626 instantiate_pending_templates ()
9629 int instantiated_something = 0;
9636 t = &pending_templates;
9639 tree srcloc = TREE_PURPOSE (*t);
9640 tree instantiation = TREE_VALUE (*t);
9642 input_filename = SRCLOC_FILE (srcloc);
9643 lineno = SRCLOC_LINE (srcloc);
9645 if (TREE_CODE_CLASS (TREE_CODE (instantiation)) == 't')
9649 if (!TYPE_SIZE (instantiation))
9651 instantiate_class_template (instantiation);
9652 if (CLASSTYPE_TEMPLATE_INSTANTIATION (instantiation))
9653 for (fn = TYPE_METHODS (instantiation);
9655 fn = TREE_CHAIN (fn))
9656 if (! DECL_ARTIFICIAL (fn))
9657 instantiate_decl (fn);
9658 if (TYPE_SIZE (instantiation))
9660 instantiated_something = 1;
9665 if (TYPE_SIZE (instantiation))
9666 /* If INSTANTIATION has been instantiated, then we don't
9667 need to consider it again in the future. */
9668 *t = TREE_CHAIN (*t);
9670 t = &TREE_CHAIN (*t);
9674 if (DECL_TEMPLATE_INSTANTIATION (instantiation)
9675 && !DECL_TEMPLATE_INSTANTIATED (instantiation))
9677 instantiation = instantiate_decl (instantiation);
9678 if (DECL_TEMPLATE_INSTANTIATED (instantiation))
9680 instantiated_something = 1;
9685 if (!DECL_TEMPLATE_INSTANTIATION (instantiation)
9686 || DECL_TEMPLATE_INSTANTIATED (instantiation))
9687 /* If INSTANTIATION has been instantiated, then we don't
9688 need to consider it again in the future. */
9689 *t = TREE_CHAIN (*t);
9691 t = &TREE_CHAIN (*t);
9696 /* Go through the things that are template instantiations if we are
9697 using guiding declarations. */
9698 t = &maybe_templates;
9705 fn = TREE_VALUE (*t);
9707 if (DECL_INITIAL (fn))
9708 /* If the FN is already defined, then it was either already
9709 instantiated or, even though guiding declarations were
9710 allowed, a non-template definition was provided. */
9714 template = TREE_PURPOSE (*t);
9715 args = get_bindings (template, fn, NULL_TREE);
9716 fn = instantiate_template (template, args);
9717 instantiate_decl (fn);
9721 /* Remove this entry from the chain. */
9722 *t = TREE_CHAIN (*t);
9724 maybe_template_tail = t;
9728 return instantiated_something;
9731 /* Substitute ARGVEC into T, which is a TREE_LIST. In particular, it
9732 is an initializer list: the TREE_PURPOSEs are DECLs, and the
9733 TREE_VALUEs are initializer values. Used by instantiate_decl. */
9736 tsubst_expr_values (t, argvec)
9739 tree first = NULL_TREE;
9742 for (; t; t = TREE_CHAIN (t))
9744 tree pur = tsubst_copy (TREE_PURPOSE (t), argvec,
9745 /*complain=*/1, NULL_TREE);
9746 tree val = tsubst_expr (TREE_VALUE (t), argvec, /*complain=*/1,
9748 *p = build_tree_list (pur, val);
9749 p = &TREE_CHAIN (*p);
9754 /* D is an undefined function declaration in the presence of templates with
9755 the same name, listed in FNS. If one of them can produce D as an
9756 instantiation, remember this so we can instantiate it at EOF if D has
9757 not been defined by that time. */
9760 add_maybe_template (d, fns)
9765 if (DECL_MAYBE_TEMPLATE (d))
9768 t = most_specialized (fns, d, NULL_TREE);
9771 if (t == error_mark_node)
9773 cp_error ("ambiguous template instantiation for `%D'", d);
9777 *maybe_template_tail = tree_cons (t, d, NULL_TREE);
9778 maybe_template_tail = &TREE_CHAIN (*maybe_template_tail);
9779 DECL_MAYBE_TEMPLATE (d) = 1;
9782 /* Set CURRENT_ACCESS_SPECIFIER based on the protection of DECL. */
9785 set_current_access_from_decl (decl)
9788 if (TREE_PRIVATE (decl))
9789 current_access_specifier = access_private_node;
9790 else if (TREE_PROTECTED (decl))
9791 current_access_specifier = access_protected_node;
9793 current_access_specifier = access_public_node;
9796 /* Instantiate an enumerated type. TAG is the template type, NEWTAG
9797 is the instantiation (which should have been created with
9798 start_enum) and ARGS are the template arguments to use. */
9801 tsubst_enum (tag, newtag, args)
9808 for (e = TYPE_VALUES (tag); e; e = TREE_CHAIN (e))
9812 /* Note that in a template enum, the TREE_VALUE is the
9813 CONST_DECL, not the corresponding INTEGER_CST. */
9814 value = tsubst_expr (DECL_INITIAL (TREE_VALUE (e)),
9815 args, /*complain=*/1,
9818 /* Give this enumeration constant the correct access. */
9819 set_current_access_from_decl (TREE_VALUE (e));
9821 /* Actually build the enumerator itself. */
9822 build_enumerator (TREE_PURPOSE (e), value, newtag);
9825 finish_enum (newtag);
9828 /* Set the DECL_ASSEMBLER_NAME for DECL, which is a FUNCTION_DECL that
9829 is either an instantiation or specialization of a template
9833 set_mangled_name_for_template_decl (decl)
9836 tree saved_namespace;
9837 tree context = NULL_TREE;
9846 my_friendly_assert (TREE_CODE (decl) == FUNCTION_DECL, 0);
9847 my_friendly_assert (DECL_TEMPLATE_INFO (decl) != NULL_TREE, 0);
9849 /* The names of template functions must be mangled so as to indicate
9850 what template is being specialized with what template arguments.
9851 For example, each of the following three functions must get
9852 different mangled names:
9855 template <> void f<7>(int);
9856 template <> void f<8>(int); */
9858 targs = DECL_TI_ARGS (decl);
9859 if (uses_template_parms (targs))
9860 /* This DECL is for a partial instantiation. There's no need to
9861 mangle the name of such an entity. */
9864 tmpl = most_general_template (DECL_TI_TEMPLATE (decl));
9865 tparms = DECL_TEMPLATE_PARMS (tmpl);
9866 parm_depth = TMPL_PARMS_DEPTH (tparms);
9868 /* There should be as many levels of arguments as there are levels
9870 my_friendly_assert (parm_depth == TMPL_ARGS_DEPTH (targs), 0);
9872 /* We now compute the PARMS and RET_TYPE to give to
9873 build_decl_overload_real. The PARMS and RET_TYPE are the
9874 parameter and return types of the template, after all but the
9875 innermost template arguments have been substituted, not the
9876 parameter and return types of the function DECL. For example,
9879 template <class T> T f(T);
9881 both PARMS and RET_TYPE should be `T' even if DECL is `int f(int)'.
9882 A more subtle example is:
9884 template <class T> struct S { template <class U> void f(T, U); }
9886 Here, if DECL is `void S<int>::f(int, double)', PARMS should be
9887 {int, U}. Thus, the args that we want to subsitute into the
9888 return and parameter type for the function are those in TARGS,
9889 with the innermost level omitted. */
9890 fn_type = TREE_TYPE (tmpl);
9891 if (DECL_STATIC_FUNCTION_P (decl))
9892 context = DECL_CONTEXT (decl);
9894 if (parm_depth == 1)
9895 /* No substitution is necessary. */
9902 /* Replace the innermost level of the TARGS with NULL_TREEs to
9903 let tsubst know not to subsitute for those parameters. */
9904 partial_args = make_tree_vec (TREE_VEC_LENGTH (targs));
9905 for (i = 1; i < TMPL_ARGS_DEPTH (targs); ++i)
9906 SET_TMPL_ARGS_LEVEL (partial_args, i,
9907 TMPL_ARGS_LEVEL (targs, i));
9908 SET_TMPL_ARGS_LEVEL (partial_args,
9909 TMPL_ARGS_DEPTH (targs),
9910 make_tree_vec (DECL_NTPARMS (tmpl)));
9912 /* Now, do the (partial) substitution to figure out the
9913 appropriate function type. */
9914 fn_type = tsubst (fn_type, partial_args, /*complain=*/1, NULL_TREE);
9915 if (DECL_STATIC_FUNCTION_P (decl))
9916 context = tsubst (context, partial_args, /*complain=*/1, NULL_TREE);
9918 /* Substitute into the template parameters to obtain the real
9919 innermost set of parameters. This step is important if the
9920 innermost set of template parameters contains value
9921 parameters whose types depend on outer template parameters. */
9922 TREE_VEC_LENGTH (partial_args)--;
9923 tparms = tsubst_template_parms (tparms, partial_args, /*complain=*/1);
9926 /* Now, get the innermost parameters and arguments, and figure out
9927 the parameter and return types. */
9928 tparms = INNERMOST_TEMPLATE_PARMS (tparms);
9929 targs = innermost_args (targs);
9930 ret_type = TREE_TYPE (fn_type);
9931 parm_types = TYPE_ARG_TYPES (fn_type);
9933 /* For a static member function, we generate a fake `this' pointer,
9934 for the purposes of mangling. This indicates of which class the
9935 function is a member. Because of:
9939 There shall not be a static and a nonstatic member function
9940 with the same name and the same parameter types
9942 we don't have to worry that this will result in a clash with a
9943 non-static member function. */
9944 if (DECL_STATIC_FUNCTION_P (decl))
9945 parm_types = hash_tree_chain (build_pointer_type (context), parm_types);
9947 /* There should be the same number of template parameters as
9948 template arguments. */
9949 my_friendly_assert (TREE_VEC_LENGTH (tparms) == TREE_VEC_LENGTH (targs),
9952 /* If the template is in a namespace, we need to put that into the
9953 mangled name. Unfortunately, build_decl_overload_real does not
9954 get the decl to mangle, so it relies on the current
9955 namespace. Therefore, we set that here temporarily. */
9956 my_friendly_assert (TREE_CODE_CLASS (TREE_CODE (decl)) == 'd', 980702);
9957 saved_namespace = current_namespace;
9958 current_namespace = CP_DECL_CONTEXT (decl);
9960 /* Actually set the DCL_ASSEMBLER_NAME. */
9961 DECL_ASSEMBLER_NAME (decl)
9962 = build_decl_overload_real (DECL_NAME (decl), parm_types, ret_type,
9964 DECL_FUNCTION_MEMBER_P (decl)
9965 + DECL_CONSTRUCTOR_P (decl));
9967 /* Restore the previously active namespace. */
9968 current_namespace = saved_namespace;