1 /* Handle parameterized types (templates) for GNU C++.
2 Copyright (C) 1992, 1993, 1994, 1995, 1996, 1997, 1998, 1999, 2000,
3 2001, 2002, 2003, 2004, 2005 Free Software Foundation, Inc.
4 Written by Ken Raeburn (raeburn@cygnus.com) while at Watchmaker Computing.
5 Rewritten by Jason Merrill (jason@cygnus.com).
7 This file is part of GCC.
9 GCC is free software; you can redistribute it and/or modify
10 it under the terms of the GNU General Public License as published by
11 the Free Software Foundation; either version 2, or (at your option)
14 GCC is distributed in the hope that it will be useful,
15 but WITHOUT ANY WARRANTY; without even the implied warranty of
16 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
17 GNU General Public License for more details.
19 You should have received a copy of the GNU General Public License
20 along with GCC; see the file COPYING. If not, write to
21 the Free Software Foundation, 51 Franklin Street, Fifth Floor,
22 Boston, MA 02110-1301, USA. */
24 /* Known bugs or deficiencies include:
26 all methods must be provided in header files; can't use a source
27 file that contains only the method templates and "just win". */
31 #include "coretypes.h"
35 #include "pointer-set.h"
39 #include "cp-objcp-common.h"
40 #include "tree-inline.h"
47 #include "tree-iterator.h"
49 /* The type of functions taking a tree, and some additional data, and
51 typedef int (*tree_fn_t) (tree, void*);
53 /* The PENDING_TEMPLATES is a TREE_LIST of templates whose
54 instantiations have been deferred, either because their definitions
55 were not yet available, or because we were putting off doing the work.
56 The TREE_PURPOSE of each entry is either a DECL (for a function or
57 static data member), or a TYPE (for a class) indicating what we are
58 hoping to instantiate. The TREE_VALUE is not used. */
59 static GTY(()) tree pending_templates;
60 static GTY(()) tree last_pending_template;
62 int processing_template_parmlist;
63 static int template_header_count;
65 static GTY(()) tree saved_trees;
66 static GTY(()) varray_type inline_parm_levels;
67 static size_t inline_parm_levels_used;
69 static GTY(()) tree current_tinst_level;
71 static GTY(()) tree saved_access_scope;
73 /* Live only within one (recursive) call to tsubst_expr. We use
74 this to pass the statement expression node from the STMT_EXPR
75 to the EXPR_STMT that is its result. */
76 static tree cur_stmt_expr;
78 /* A map from local variable declarations in the body of the template
79 presently being instantiated to the corresponding instantiated
81 static htab_t local_specializations;
83 #define UNIFY_ALLOW_NONE 0
84 #define UNIFY_ALLOW_MORE_CV_QUAL 1
85 #define UNIFY_ALLOW_LESS_CV_QUAL 2
86 #define UNIFY_ALLOW_DERIVED 4
87 #define UNIFY_ALLOW_INTEGER 8
88 #define UNIFY_ALLOW_OUTER_LEVEL 16
89 #define UNIFY_ALLOW_OUTER_MORE_CV_QUAL 32
90 #define UNIFY_ALLOW_OUTER_LESS_CV_QUAL 64
92 static void push_access_scope (tree);
93 static void pop_access_scope (tree);
94 static int resolve_overloaded_unification (tree, tree, tree, tree,
95 unification_kind_t, int);
96 static int try_one_overload (tree, tree, tree, tree, tree,
97 unification_kind_t, int, bool);
98 static int unify (tree, tree, tree, tree, int);
99 static void add_pending_template (tree);
100 static void reopen_tinst_level (tree);
101 static tree classtype_mangled_name (tree);
102 static char* mangle_class_name_for_template (const char *, tree, tree);
103 static tree tsubst_initializer_list (tree, tree);
104 static tree get_class_bindings (tree, tree, tree);
105 static tree coerce_template_parms (tree, tree, tree, tsubst_flags_t, int);
106 static void tsubst_enum (tree, tree, tree);
107 static tree add_to_template_args (tree, tree);
108 static tree add_outermost_template_args (tree, tree);
109 static bool check_instantiated_args (tree, tree, tsubst_flags_t);
110 static int maybe_adjust_types_for_deduction (unification_kind_t, tree*, tree*);
111 static int type_unification_real (tree, tree, tree, tree,
112 int, unification_kind_t, int);
113 static void note_template_header (int);
114 static tree convert_nontype_argument_function (tree, tree);
115 static tree convert_nontype_argument (tree, tree);
116 static tree convert_template_argument (tree, tree, tree,
117 tsubst_flags_t, int, tree);
118 static int for_each_template_parm (tree, tree_fn_t, void*,
119 struct pointer_set_t*);
120 static tree build_template_parm_index (int, int, int, tree, tree);
121 static int inline_needs_template_parms (tree);
122 static void push_inline_template_parms_recursive (tree, int);
123 static tree retrieve_local_specialization (tree);
124 static void register_local_specialization (tree, tree);
125 static tree reduce_template_parm_level (tree, tree, int);
126 static int mark_template_parm (tree, void *);
127 static int template_parm_this_level_p (tree, void *);
128 static tree tsubst_friend_function (tree, tree);
129 static tree tsubst_friend_class (tree, tree);
130 static int can_complete_type_without_circularity (tree);
131 static tree get_bindings (tree, tree, tree, bool);
132 static int template_decl_level (tree);
133 static int check_cv_quals_for_unify (int, tree, tree);
134 static tree tsubst_template_arg (tree, tree, tsubst_flags_t, tree);
135 static tree tsubst_template_args (tree, tree, tsubst_flags_t, tree);
136 static tree tsubst_template_parms (tree, tree, tsubst_flags_t);
137 static void regenerate_decl_from_template (tree, tree);
138 static tree most_specialized (tree, tree, tree);
139 static tree most_specialized_class (tree, tree);
140 static int template_class_depth_real (tree, int);
141 static tree tsubst_aggr_type (tree, tree, tsubst_flags_t, tree, int);
142 static tree tsubst_arg_types (tree, tree, tsubst_flags_t, tree);
143 static tree tsubst_function_type (tree, tree, tsubst_flags_t, tree);
144 static void check_specialization_scope (void);
145 static tree process_partial_specialization (tree);
146 static void set_current_access_from_decl (tree);
147 static void check_default_tmpl_args (tree, tree, int, int);
148 static tree tsubst_call_declarator_parms (tree, tree, tsubst_flags_t, tree);
149 static tree get_template_base (tree, tree, tree, tree);
150 static int verify_class_unification (tree, tree, tree);
151 static tree try_class_unification (tree, tree, tree, tree);
152 static int coerce_template_template_parms (tree, tree, tsubst_flags_t,
154 static tree determine_specialization (tree, tree, tree *, int, int);
155 static int template_args_equal (tree, tree);
156 static void tsubst_default_arguments (tree);
157 static tree for_each_template_parm_r (tree *, int *, void *);
158 static tree copy_default_args_to_explicit_spec_1 (tree, tree);
159 static void copy_default_args_to_explicit_spec (tree);
160 static int invalid_nontype_parm_type_p (tree, tsubst_flags_t);
161 static int eq_local_specializations (const void *, const void *);
162 static bool dependent_type_p_r (tree);
163 static tree tsubst (tree, tree, tsubst_flags_t, tree);
164 static tree tsubst_expr (tree, tree, tsubst_flags_t, tree);
165 static tree tsubst_copy (tree, tree, tsubst_flags_t, tree);
167 /* Make the current scope suitable for access checking when we are
168 processing T. T can be FUNCTION_DECL for instantiated function
169 template, or VAR_DECL for static member variable (need by
170 instantiate_decl). */
173 push_access_scope (tree t)
175 gcc_assert (TREE_CODE (t) == FUNCTION_DECL
176 || TREE_CODE (t) == VAR_DECL);
178 if (DECL_FRIEND_CONTEXT (t))
179 push_nested_class (DECL_FRIEND_CONTEXT (t));
180 else if (DECL_CLASS_SCOPE_P (t))
181 push_nested_class (DECL_CONTEXT (t));
183 push_to_top_level ();
185 if (TREE_CODE (t) == FUNCTION_DECL)
187 saved_access_scope = tree_cons
188 (NULL_TREE, current_function_decl, saved_access_scope);
189 current_function_decl = t;
193 /* Restore the scope set up by push_access_scope. T is the node we
197 pop_access_scope (tree t)
199 if (TREE_CODE (t) == FUNCTION_DECL)
201 current_function_decl = TREE_VALUE (saved_access_scope);
202 saved_access_scope = TREE_CHAIN (saved_access_scope);
205 if (DECL_FRIEND_CONTEXT (t) || DECL_CLASS_SCOPE_P (t))
208 pop_from_top_level ();
211 /* Do any processing required when DECL (a member template
212 declaration) is finished. Returns the TEMPLATE_DECL corresponding
213 to DECL, unless it is a specialization, in which case the DECL
214 itself is returned. */
217 finish_member_template_decl (tree decl)
219 if (decl == error_mark_node)
220 return error_mark_node;
222 gcc_assert (DECL_P (decl));
224 if (TREE_CODE (decl) == TYPE_DECL)
228 type = TREE_TYPE (decl);
229 if (IS_AGGR_TYPE (type)
230 && CLASSTYPE_TEMPLATE_INFO (type)
231 && !CLASSTYPE_TEMPLATE_SPECIALIZATION (type))
233 tree tmpl = CLASSTYPE_TI_TEMPLATE (type);
234 check_member_template (tmpl);
239 else if (TREE_CODE (decl) == FIELD_DECL)
240 error ("data member %qD cannot be a member template", decl);
241 else if (DECL_TEMPLATE_INFO (decl))
243 if (!DECL_TEMPLATE_SPECIALIZATION (decl))
245 check_member_template (DECL_TI_TEMPLATE (decl));
246 return DECL_TI_TEMPLATE (decl);
252 error ("invalid member template declaration %qD", decl);
254 return error_mark_node;
257 /* Returns the template nesting level of the indicated class TYPE.
267 A<T>::B<U> has depth two, while A<T> has depth one.
268 Both A<T>::B<int> and A<int>::B<U> have depth one, if
269 COUNT_SPECIALIZATIONS is 0 or if they are instantiations, not
272 This function is guaranteed to return 0 if passed NULL_TREE so
273 that, for example, `template_class_depth (current_class_type)' is
277 template_class_depth_real (tree type, int count_specializations)
282 type && TREE_CODE (type) != NAMESPACE_DECL;
283 type = (TREE_CODE (type) == FUNCTION_DECL)
284 ? CP_DECL_CONTEXT (type) : TYPE_CONTEXT (type))
286 if (TREE_CODE (type) != FUNCTION_DECL)
288 if (CLASSTYPE_TEMPLATE_INFO (type)
289 && PRIMARY_TEMPLATE_P (CLASSTYPE_TI_TEMPLATE (type))
290 && ((count_specializations
291 && CLASSTYPE_TEMPLATE_SPECIALIZATION (type))
292 || uses_template_parms (CLASSTYPE_TI_ARGS (type))))
297 if (DECL_TEMPLATE_INFO (type)
298 && PRIMARY_TEMPLATE_P (DECL_TI_TEMPLATE (type))
299 && ((count_specializations
300 && DECL_TEMPLATE_SPECIALIZATION (type))
301 || uses_template_parms (DECL_TI_ARGS (type))))
309 /* Returns the template nesting level of the indicated class TYPE.
310 Like template_class_depth_real, but instantiations do not count in
314 template_class_depth (tree type)
316 return template_class_depth_real (type, /*count_specializations=*/0);
319 /* Returns 1 if processing DECL as part of do_pending_inlines
320 needs us to push template parms. */
323 inline_needs_template_parms (tree decl)
325 if (! DECL_TEMPLATE_INFO (decl))
328 return (TMPL_PARMS_DEPTH (DECL_TEMPLATE_PARMS (most_general_template (decl)))
329 > (processing_template_decl + DECL_TEMPLATE_SPECIALIZATION (decl)));
332 /* Subroutine of maybe_begin_member_template_processing.
333 Push the template parms in PARMS, starting from LEVELS steps into the
334 chain, and ending at the beginning, since template parms are listed
338 push_inline_template_parms_recursive (tree parmlist, int levels)
340 tree parms = TREE_VALUE (parmlist);
344 push_inline_template_parms_recursive (TREE_CHAIN (parmlist), levels - 1);
346 ++processing_template_decl;
347 current_template_parms
348 = tree_cons (size_int (processing_template_decl),
349 parms, current_template_parms);
350 TEMPLATE_PARMS_FOR_INLINE (current_template_parms) = 1;
352 begin_scope (TREE_VEC_LENGTH (parms) ? sk_template_parms : sk_template_spec,
354 for (i = 0; i < TREE_VEC_LENGTH (parms); ++i)
356 tree parm = TREE_VALUE (TREE_VEC_ELT (parms, i));
357 gcc_assert (DECL_P (parm));
359 switch (TREE_CODE (parm))
368 /* Make a CONST_DECL as is done in process_template_parm.
369 It is ugly that we recreate this here; the original
370 version built in process_template_parm is no longer
372 tree decl = build_decl (CONST_DECL, DECL_NAME (parm),
374 DECL_ARTIFICIAL (decl) = 1;
375 TREE_CONSTANT (decl) = 1;
376 TREE_INVARIANT (decl) = 1;
377 TREE_READONLY (decl) = 1;
378 DECL_INITIAL (decl) = DECL_INITIAL (parm);
379 SET_DECL_TEMPLATE_PARM_P (decl);
390 /* Restore the template parameter context for a member template or
391 a friend template defined in a class definition. */
394 maybe_begin_member_template_processing (tree decl)
399 if (inline_needs_template_parms (decl))
401 parms = DECL_TEMPLATE_PARMS (most_general_template (decl));
402 levels = TMPL_PARMS_DEPTH (parms) - processing_template_decl;
404 if (DECL_TEMPLATE_SPECIALIZATION (decl))
407 parms = TREE_CHAIN (parms);
410 push_inline_template_parms_recursive (parms, levels);
413 /* Remember how many levels of template parameters we pushed so that
414 we can pop them later. */
415 if (!inline_parm_levels)
416 VARRAY_INT_INIT (inline_parm_levels, 4, "inline_parm_levels");
417 if (inline_parm_levels_used == inline_parm_levels->num_elements)
418 VARRAY_GROW (inline_parm_levels, 2 * inline_parm_levels_used);
419 VARRAY_INT (inline_parm_levels, inline_parm_levels_used) = levels;
420 ++inline_parm_levels_used;
423 /* Undo the effects of maybe_begin_member_template_processing. */
426 maybe_end_member_template_processing (void)
430 if (!inline_parm_levels_used)
433 --inline_parm_levels_used;
435 i < VARRAY_INT (inline_parm_levels, inline_parm_levels_used);
438 --processing_template_decl;
439 current_template_parms = TREE_CHAIN (current_template_parms);
444 /* Return a new template argument vector which contains all of ARGS,
445 but has as its innermost set of arguments the EXTRA_ARGS. */
448 add_to_template_args (tree args, tree extra_args)
455 extra_depth = TMPL_ARGS_DEPTH (extra_args);
456 new_args = make_tree_vec (TMPL_ARGS_DEPTH (args) + extra_depth);
458 for (i = 1; i <= TMPL_ARGS_DEPTH (args); ++i)
459 SET_TMPL_ARGS_LEVEL (new_args, i, TMPL_ARGS_LEVEL (args, i));
461 for (j = 1; j <= extra_depth; ++j, ++i)
462 SET_TMPL_ARGS_LEVEL (new_args, i, TMPL_ARGS_LEVEL (extra_args, j));
467 /* Like add_to_template_args, but only the outermost ARGS are added to
468 the EXTRA_ARGS. In particular, all but TMPL_ARGS_DEPTH
469 (EXTRA_ARGS) levels are added. This function is used to combine
470 the template arguments from a partial instantiation with the
471 template arguments used to attain the full instantiation from the
472 partial instantiation. */
475 add_outermost_template_args (tree args, tree extra_args)
479 /* If there are more levels of EXTRA_ARGS than there are ARGS,
480 something very fishy is going on. */
481 gcc_assert (TMPL_ARGS_DEPTH (args) >= TMPL_ARGS_DEPTH (extra_args));
483 /* If *all* the new arguments will be the EXTRA_ARGS, just return
485 if (TMPL_ARGS_DEPTH (args) == TMPL_ARGS_DEPTH (extra_args))
488 /* For the moment, we make ARGS look like it contains fewer levels. */
489 TREE_VEC_LENGTH (args) -= TMPL_ARGS_DEPTH (extra_args);
491 new_args = add_to_template_args (args, extra_args);
493 /* Now, we restore ARGS to its full dimensions. */
494 TREE_VEC_LENGTH (args) += TMPL_ARGS_DEPTH (extra_args);
499 /* Return the N levels of innermost template arguments from the ARGS. */
502 get_innermost_template_args (tree args, int n)
510 /* If N is 1, just return the innermost set of template arguments. */
512 return TMPL_ARGS_LEVEL (args, TMPL_ARGS_DEPTH (args));
514 /* If we're not removing anything, just return the arguments we were
516 extra_levels = TMPL_ARGS_DEPTH (args) - n;
517 gcc_assert (extra_levels >= 0);
518 if (extra_levels == 0)
521 /* Make a new set of arguments, not containing the outer arguments. */
522 new_args = make_tree_vec (n);
523 for (i = 1; i <= n; ++i)
524 SET_TMPL_ARGS_LEVEL (new_args, i,
525 TMPL_ARGS_LEVEL (args, i + extra_levels));
530 /* We've got a template header coming up; push to a new level for storing
534 begin_template_parm_list (void)
536 /* We use a non-tag-transparent scope here, which causes pushtag to
537 put tags in this scope, rather than in the enclosing class or
538 namespace scope. This is the right thing, since we want
539 TEMPLATE_DECLS, and not TYPE_DECLS for template classes. For a
540 global template class, push_template_decl handles putting the
541 TEMPLATE_DECL into top-level scope. For a nested template class,
544 template <class T> struct S1 {
545 template <class T> struct S2 {};
548 pushtag contains special code to call pushdecl_with_scope on the
549 TEMPLATE_DECL for S2. */
550 begin_scope (sk_template_parms, NULL);
551 ++processing_template_decl;
552 ++processing_template_parmlist;
553 note_template_header (0);
556 /* This routine is called when a specialization is declared. If it is
557 invalid to declare a specialization here, an error is reported. */
560 check_specialization_scope (void)
562 tree scope = current_scope ();
566 An explicit specialization shall be declared in the namespace of
567 which the template is a member, or, for member templates, in the
568 namespace of which the enclosing class or enclosing class
569 template is a member. An explicit specialization of a member
570 function, member class or static data member of a class template
571 shall be declared in the namespace of which the class template
573 if (scope && TREE_CODE (scope) != NAMESPACE_DECL)
574 error ("explicit specialization in non-namespace scope %qD", scope);
578 In an explicit specialization declaration for a member of a class
579 template or a member template that appears in namespace scope,
580 the member template and some of its enclosing class templates may
581 remain unspecialized, except that the declaration shall not
582 explicitly specialize a class member template if its enclosing
583 class templates are not explicitly specialized as well. */
584 if (current_template_parms)
585 error ("enclosing class templates are not explicitly specialized");
588 /* We've just seen template <>. */
591 begin_specialization (void)
593 begin_scope (sk_template_spec, NULL);
594 note_template_header (1);
595 check_specialization_scope ();
598 /* Called at then end of processing a declaration preceded by
602 end_specialization (void)
605 reset_specialization ();
608 /* Any template <>'s that we have seen thus far are not referring to a
609 function specialization. */
612 reset_specialization (void)
614 processing_specialization = 0;
615 template_header_count = 0;
618 /* We've just seen a template header. If SPECIALIZATION is nonzero,
619 it was of the form template <>. */
622 note_template_header (int specialization)
624 processing_specialization = specialization;
625 template_header_count++;
628 /* We're beginning an explicit instantiation. */
631 begin_explicit_instantiation (void)
633 gcc_assert (!processing_explicit_instantiation);
634 processing_explicit_instantiation = true;
639 end_explicit_instantiation (void)
641 gcc_assert (processing_explicit_instantiation);
642 processing_explicit_instantiation = false;
645 /* An explicit specialization or partial specialization TMPL is being
646 declared. Check that the namespace in which the specialization is
647 occurring is permissible. Returns false iff it is invalid to
648 specialize TMPL in the current namespace. */
651 check_specialization_namespace (tree tmpl)
653 tree tpl_ns = decl_namespace_context (tmpl);
657 An explicit specialization shall be declared in the namespace of
658 which the template is a member, or, for member templates, in the
659 namespace of which the enclosing class or enclosing class
660 template is a member. An explicit specialization of a member
661 function, member class or static data member of a class template
662 shall be declared in the namespace of which the class template is
664 if (is_associated_namespace (current_namespace, tpl_ns))
665 /* Same or super-using namespace. */
669 pedwarn ("specialization of %qD in different namespace", tmpl);
670 pedwarn (" from definition of %q+#D", tmpl);
675 /* SPEC is an explicit instantiation. Check that it is valid to
676 perform this explicit instantiation in the current namespace. */
679 check_explicit_instantiation_namespace (tree spec)
683 /* DR 275: An explicit instantiation shall appear in an enclosing
684 namespace of its template. */
685 ns = decl_namespace_context (spec);
686 if (!is_ancestor (current_namespace, ns))
687 pedwarn ("explicit instantiation of %qD in namespace %qD "
688 "(which does not enclose namespace %qD)",
689 spec, current_namespace, ns);
692 /* The TYPE is being declared. If it is a template type, that means it
693 is a partial specialization. Do appropriate error-checking. */
696 maybe_process_partial_specialization (tree type)
698 /* TYPE maybe an ERROR_MARK_NODE. */
699 tree context = TYPE_P (type) ? TYPE_CONTEXT (type) : NULL_TREE;
701 if (CLASS_TYPE_P (type) && CLASSTYPE_USE_TEMPLATE (type))
703 /* This is for ordinary explicit specialization and partial
704 specialization of a template class such as:
706 template <> class C<int>;
710 template <class T> class C<T*>;
712 Make sure that `C<int>' and `C<T*>' are implicit instantiations. */
714 if (CLASSTYPE_IMPLICIT_INSTANTIATION (type)
715 && !COMPLETE_TYPE_P (type))
717 check_specialization_namespace (CLASSTYPE_TI_TEMPLATE (type));
718 SET_CLASSTYPE_TEMPLATE_SPECIALIZATION (type);
719 if (processing_template_decl)
720 push_template_decl (TYPE_MAIN_DECL (type));
722 else if (CLASSTYPE_TEMPLATE_INSTANTIATION (type))
723 error ("specialization of %qT after instantiation", type);
725 else if (CLASS_TYPE_P (type)
726 && !CLASSTYPE_USE_TEMPLATE (type)
727 && CLASSTYPE_TEMPLATE_INFO (type)
728 && context && CLASS_TYPE_P (context)
729 && CLASSTYPE_TEMPLATE_INFO (context))
731 /* This is for an explicit specialization of member class
732 template according to [temp.expl.spec/18]:
734 template <> template <class U> class C<int>::D;
736 The context `C<int>' must be an implicit instantiation.
737 Otherwise this is just a member class template declared
740 template <> class C<int> { template <class U> class D; };
741 template <> template <class U> class C<int>::D;
743 In the first case, `C<int>::D' is a specialization of `C<T>::D'
744 while in the second case, `C<int>::D' is a primary template
745 and `C<T>::D' may not exist. */
747 if (CLASSTYPE_IMPLICIT_INSTANTIATION (context)
748 && !COMPLETE_TYPE_P (type))
752 if (current_namespace
753 != decl_namespace_context (CLASSTYPE_TI_TEMPLATE (type)))
755 pedwarn ("specializing %q#T in different namespace", type);
756 pedwarn (" from definition of %q+#D",
757 CLASSTYPE_TI_TEMPLATE (type));
760 /* Check for invalid specialization after instantiation:
762 template <> template <> class C<int>::D<int>;
763 template <> template <class U> class C<int>::D; */
765 for (t = DECL_TEMPLATE_INSTANTIATIONS
766 (most_general_template (CLASSTYPE_TI_TEMPLATE (type)));
767 t; t = TREE_CHAIN (t))
768 if (TREE_VALUE (t) != type
769 && TYPE_CONTEXT (TREE_VALUE (t)) == context)
770 error ("specialization %qT after instantiation %qT",
771 type, TREE_VALUE (t));
773 /* Mark TYPE as a specialization. And as a result, we only
774 have one level of template argument for the innermost
776 SET_CLASSTYPE_TEMPLATE_SPECIALIZATION (type);
777 CLASSTYPE_TI_ARGS (type)
778 = INNERMOST_TEMPLATE_ARGS (CLASSTYPE_TI_ARGS (type));
781 else if (processing_specialization)
782 error ("explicit specialization of non-template %qT", type);
785 /* Returns nonzero if we can optimize the retrieval of specializations
786 for TMPL, a TEMPLATE_DECL. In particular, for such a template, we
787 do not use DECL_TEMPLATE_SPECIALIZATIONS at all. */
790 optimize_specialization_lookup_p (tree tmpl)
792 return (DECL_FUNCTION_TEMPLATE_P (tmpl)
793 && DECL_CLASS_SCOPE_P (tmpl)
794 /* DECL_CLASS_SCOPE_P holds of T::f even if T is a template
796 && CLASS_TYPE_P (DECL_CONTEXT (tmpl))
797 /* The optimized lookup depends on the fact that the
798 template arguments for the member function template apply
799 purely to the containing class, which is not true if the
800 containing class is an explicit or partial
802 && !CLASSTYPE_TEMPLATE_SPECIALIZATION (DECL_CONTEXT (tmpl))
803 && !DECL_MEMBER_TEMPLATE_P (tmpl)
804 && !DECL_CONV_FN_P (tmpl)
805 /* It is possible to have a template that is not a member
806 template and is not a member of a template class:
808 template <typename T>
809 struct S { friend A::f(); };
811 Here, the friend function is a template, but the context does
812 not have template information. The optimized lookup relies
813 on having ARGS be the template arguments for both the class
814 and the function template. */
815 && !DECL_FRIEND_P (DECL_TEMPLATE_RESULT (tmpl)));
818 /* Retrieve the specialization (in the sense of [temp.spec] - a
819 specialization is either an instantiation or an explicit
820 specialization) of TMPL for the given template ARGS. If there is
821 no such specialization, return NULL_TREE. The ARGS are a vector of
822 arguments, or a vector of vectors of arguments, in the case of
823 templates with more than one level of parameters.
825 If TMPL is a type template and CLASS_SPECIALIZATIONS_P is true,
826 then we search for a partial specialization matching ARGS. This
827 parameter is ignored if TMPL is not a class template. */
830 retrieve_specialization (tree tmpl, tree args,
831 bool class_specializations_p)
833 gcc_assert (TREE_CODE (tmpl) == TEMPLATE_DECL);
835 /* There should be as many levels of arguments as there are
836 levels of parameters. */
837 gcc_assert (TMPL_ARGS_DEPTH (args)
838 == TMPL_PARMS_DEPTH (DECL_TEMPLATE_PARMS (tmpl)));
840 if (optimize_specialization_lookup_p (tmpl))
843 tree class_specialization;
844 VEC(tree,gc) *methods;
848 /* The template arguments actually apply to the containing
849 class. Find the class specialization with those
851 class_template = CLASSTYPE_TI_TEMPLATE (DECL_CONTEXT (tmpl));
853 = retrieve_specialization (class_template, args,
854 /*class_specializations_p=*/false);
855 if (!class_specialization)
857 /* Now, find the appropriate entry in the CLASSTYPE_METHOD_VEC
858 for the specialization. */
859 idx = class_method_index_for_fn (class_specialization, tmpl);
862 /* Iterate through the methods with the indicated name, looking
863 for the one that has an instance of TMPL. */
864 methods = CLASSTYPE_METHOD_VEC (class_specialization);
865 for (fns = VEC_index (tree, methods, idx); fns; fns = OVL_NEXT (fns))
867 tree fn = OVL_CURRENT (fns);
868 if (DECL_TEMPLATE_INFO (fn) && DECL_TI_TEMPLATE (fn) == tmpl)
878 /* Class templates store their instantiations on the
879 DECL_TEMPLATE_INSTANTIATIONS list; other templates use the
880 DECL_TEMPLATE_SPECIALIZATIONS list. */
881 if (!class_specializations_p
882 && TREE_CODE (DECL_TEMPLATE_RESULT (tmpl)) == TYPE_DECL)
883 sp = &DECL_TEMPLATE_INSTANTIATIONS (tmpl);
885 sp = &DECL_TEMPLATE_SPECIALIZATIONS (tmpl);
887 /* Iterate through the list until we find a matching template. */
888 while (*sp != NULL_TREE)
892 if (comp_template_args (TREE_PURPOSE (spec), args))
894 /* Use the move-to-front heuristic to speed up future
898 *sp = TREE_CHAIN (*sp);
899 TREE_CHAIN (spec) = *head;
902 return TREE_VALUE (spec);
904 sp = &TREE_CHAIN (spec);
911 /* Like retrieve_specialization, but for local declarations. */
914 retrieve_local_specialization (tree tmpl)
916 tree spec = htab_find_with_hash (local_specializations, tmpl,
917 htab_hash_pointer (tmpl));
918 return spec ? TREE_PURPOSE (spec) : NULL_TREE;
921 /* Returns nonzero iff DECL is a specialization of TMPL. */
924 is_specialization_of (tree decl, tree tmpl)
928 if (TREE_CODE (decl) == FUNCTION_DECL)
932 t = DECL_TEMPLATE_INFO (t) ? DECL_TI_TEMPLATE (t) : NULL_TREE)
938 gcc_assert (TREE_CODE (decl) == TYPE_DECL);
940 for (t = TREE_TYPE (decl);
942 t = CLASSTYPE_USE_TEMPLATE (t)
943 ? TREE_TYPE (CLASSTYPE_TI_TEMPLATE (t)) : NULL_TREE)
944 if (same_type_ignoring_top_level_qualifiers_p (t, TREE_TYPE (tmpl)))
951 /* Returns nonzero iff DECL is a specialization of friend declaration
952 FRIEND according to [temp.friend]. */
955 is_specialization_of_friend (tree decl, tree friend)
957 bool need_template = true;
960 gcc_assert (TREE_CODE (decl) == FUNCTION_DECL
961 || TREE_CODE (decl) == TYPE_DECL);
963 /* For [temp.friend/6] when FRIEND is an ordinary member function
964 of a template class, we want to check if DECL is a specialization
966 if (TREE_CODE (friend) == FUNCTION_DECL
967 && DECL_TEMPLATE_INFO (friend)
968 && !DECL_USE_TEMPLATE (friend))
970 /* We want a TEMPLATE_DECL for `is_specialization_of'. */
971 friend = DECL_TI_TEMPLATE (friend);
972 need_template = false;
974 else if (TREE_CODE (friend) == TEMPLATE_DECL
975 && !PRIMARY_TEMPLATE_P (friend))
976 need_template = false;
978 /* There is nothing to do if this is not a template friend. */
979 if (TREE_CODE (friend) != TEMPLATE_DECL)
982 if (is_specialization_of (decl, friend))
986 A member of a class template may be declared to be a friend of a
987 non-template class. In this case, the corresponding member of
988 every specialization of the class template is a friend of the
989 class granting friendship.
991 For example, given a template friend declaration
993 template <class T> friend void A<T>::f();
995 the member function below is considered a friend
997 template <> struct A<int> {
1001 For this type of template friend, TEMPLATE_DEPTH below will be
1002 nonzero. To determine if DECL is a friend of FRIEND, we first
1003 check if the enclosing class is a specialization of another. */
1005 template_depth = template_class_depth (DECL_CONTEXT (friend));
1007 && DECL_CLASS_SCOPE_P (decl)
1008 && is_specialization_of (TYPE_NAME (DECL_CONTEXT (decl)),
1009 CLASSTYPE_TI_TEMPLATE (DECL_CONTEXT (friend))))
1011 /* Next, we check the members themselves. In order to handle
1012 a few tricky cases, such as when FRIEND's are
1014 template <class T> friend void A<T>::g(T t);
1015 template <class T> template <T t> friend void A<T>::h();
1019 void A<int>::g(int);
1020 template <int> void A<int>::h();
1022 we need to figure out ARGS, the template arguments from
1023 the context of DECL. This is required for template substitution
1024 of `T' in the function parameter of `g' and template parameter
1025 of `h' in the above examples. Here ARGS corresponds to `int'. */
1027 tree context = DECL_CONTEXT (decl);
1028 tree args = NULL_TREE;
1029 int current_depth = 0;
1031 while (current_depth < template_depth)
1033 if (CLASSTYPE_TEMPLATE_INFO (context))
1035 if (current_depth == 0)
1036 args = TYPE_TI_ARGS (context);
1038 args = add_to_template_args (TYPE_TI_ARGS (context), args);
1041 context = TYPE_CONTEXT (context);
1044 if (TREE_CODE (decl) == FUNCTION_DECL)
1049 tree friend_args_type;
1050 tree decl_args_type;
1052 /* Make sure that both DECL and FRIEND are templates or
1054 is_template = DECL_TEMPLATE_INFO (decl)
1055 && PRIMARY_TEMPLATE_P (DECL_TI_TEMPLATE (decl));
1056 if (need_template ^ is_template)
1058 else if (is_template)
1060 /* If both are templates, check template parameter list. */
1062 = tsubst_template_parms (DECL_TEMPLATE_PARMS (friend),
1064 if (!comp_template_parms
1065 (DECL_TEMPLATE_PARMS (DECL_TI_TEMPLATE (decl)),
1069 decl_type = TREE_TYPE (DECL_TI_TEMPLATE (decl));
1072 decl_type = TREE_TYPE (decl);
1074 friend_type = tsubst_function_type (TREE_TYPE (friend), args,
1075 tf_none, NULL_TREE);
1076 if (friend_type == error_mark_node)
1079 /* Check if return types match. */
1080 if (!same_type_p (TREE_TYPE (decl_type), TREE_TYPE (friend_type)))
1083 /* Check if function parameter types match, ignoring the
1084 `this' parameter. */
1085 friend_args_type = TYPE_ARG_TYPES (friend_type);
1086 decl_args_type = TYPE_ARG_TYPES (decl_type);
1087 if (DECL_NONSTATIC_MEMBER_FUNCTION_P (friend))
1088 friend_args_type = TREE_CHAIN (friend_args_type);
1089 if (DECL_NONSTATIC_MEMBER_FUNCTION_P (decl))
1090 decl_args_type = TREE_CHAIN (decl_args_type);
1092 return compparms (decl_args_type, friend_args_type);
1096 /* DECL is a TYPE_DECL */
1098 tree decl_type = TREE_TYPE (decl);
1100 /* Make sure that both DECL and FRIEND are templates or
1103 = CLASSTYPE_TEMPLATE_INFO (decl_type)
1104 && PRIMARY_TEMPLATE_P (CLASSTYPE_TI_TEMPLATE (decl_type));
1106 if (need_template ^ is_template)
1108 else if (is_template)
1111 /* If both are templates, check the name of the two
1112 TEMPLATE_DECL's first because is_friend didn't. */
1113 if (DECL_NAME (CLASSTYPE_TI_TEMPLATE (decl_type))
1114 != DECL_NAME (friend))
1117 /* Now check template parameter list. */
1119 = tsubst_template_parms (DECL_TEMPLATE_PARMS (friend),
1121 return comp_template_parms
1122 (DECL_TEMPLATE_PARMS (CLASSTYPE_TI_TEMPLATE (decl_type)),
1126 return (DECL_NAME (decl)
1127 == DECL_NAME (friend));
1133 /* Register the specialization SPEC as a specialization of TMPL with
1134 the indicated ARGS. IS_FRIEND indicates whether the specialization
1135 is actually just a friend declaration. Returns SPEC, or an
1136 equivalent prior declaration, if available. */
1139 register_specialization (tree spec, tree tmpl, tree args, bool is_friend)
1143 gcc_assert (TREE_CODE (tmpl) == TEMPLATE_DECL);
1145 if (TREE_CODE (spec) == FUNCTION_DECL
1146 && uses_template_parms (DECL_TI_ARGS (spec)))
1147 /* This is the FUNCTION_DECL for a partial instantiation. Don't
1148 register it; we want the corresponding TEMPLATE_DECL instead.
1149 We use `uses_template_parms (DECL_TI_ARGS (spec))' rather than
1150 the more obvious `uses_template_parms (spec)' to avoid problems
1151 with default function arguments. In particular, given
1152 something like this:
1154 template <class T> void f(T t1, T t = T())
1156 the default argument expression is not substituted for in an
1157 instantiation unless and until it is actually needed. */
1160 fn = retrieve_specialization (tmpl, args,
1161 /*class_specializations_p=*/false);
1162 /* We can sometimes try to re-register a specialization that we've
1163 already got. In particular, regenerate_decl_from_template calls
1164 duplicate_decls which will update the specialization list. But,
1165 we'll still get called again here anyhow. It's more convenient
1166 to simply allow this than to try to prevent it. */
1169 else if (fn && DECL_TEMPLATE_SPECIALIZATION (spec))
1171 if (DECL_TEMPLATE_INSTANTIATION (fn))
1174 || DECL_EXPLICIT_INSTANTIATION (fn))
1176 error ("specialization of %qD after instantiation",
1182 /* This situation should occur only if the first
1183 specialization is an implicit instantiation, the
1184 second is an explicit specialization, and the
1185 implicit instantiation has not yet been used. That
1186 situation can occur if we have implicitly
1187 instantiated a member function and then specialized
1190 We can also wind up here if a friend declaration that
1191 looked like an instantiation turns out to be a
1194 template <class T> void foo(T);
1195 class S { friend void foo<>(int) };
1196 template <> void foo(int);
1198 We transform the existing DECL in place so that any
1199 pointers to it become pointers to the updated
1202 If there was a definition for the template, but not
1203 for the specialization, we want this to look as if
1204 there were no definition, and vice versa. */
1205 DECL_INITIAL (fn) = NULL_TREE;
1206 duplicate_decls (spec, fn, is_friend);
1207 check_specialization_namespace (fn);
1212 else if (DECL_TEMPLATE_SPECIALIZATION (fn))
1214 if (!duplicate_decls (spec, fn, is_friend) && DECL_INITIAL (spec))
1215 /* Dup decl failed, but this is a new definition. Set the
1216 line number so any errors match this new
1218 DECL_SOURCE_LOCATION (fn) = DECL_SOURCE_LOCATION (spec);
1224 /* A specialization must be declared in the same namespace as the
1225 template it is specializing. */
1226 if (DECL_TEMPLATE_SPECIALIZATION (spec)
1227 && !check_specialization_namespace (tmpl))
1228 DECL_CONTEXT (spec) = decl_namespace_context (tmpl);
1230 if (!optimize_specialization_lookup_p (tmpl))
1231 DECL_TEMPLATE_SPECIALIZATIONS (tmpl)
1232 = tree_cons (args, spec, DECL_TEMPLATE_SPECIALIZATIONS (tmpl));
1237 /* Unregister the specialization SPEC as a specialization of TMPL.
1238 Replace it with NEW_SPEC, if NEW_SPEC is non-NULL. Returns true
1239 if the SPEC was listed as a specialization of TMPL. */
1242 reregister_specialization (tree spec, tree tmpl, tree new_spec)
1246 for (s = &DECL_TEMPLATE_SPECIALIZATIONS (tmpl);
1248 s = &TREE_CHAIN (*s))
1249 if (TREE_VALUE (*s) == spec)
1252 *s = TREE_CHAIN (*s);
1254 TREE_VALUE (*s) = new_spec;
1261 /* Compare an entry in the local specializations hash table P1 (which
1262 is really a pointer to a TREE_LIST) with P2 (which is really a
1266 eq_local_specializations (const void *p1, const void *p2)
1268 return TREE_VALUE ((tree) p1) == (tree) p2;
1271 /* Hash P1, an entry in the local specializations table. */
1274 hash_local_specialization (const void* p1)
1276 return htab_hash_pointer (TREE_VALUE ((tree) p1));
1279 /* Like register_specialization, but for local declarations. We are
1280 registering SPEC, an instantiation of TMPL. */
1283 register_local_specialization (tree spec, tree tmpl)
1287 slot = htab_find_slot_with_hash (local_specializations, tmpl,
1288 htab_hash_pointer (tmpl), INSERT);
1289 *slot = build_tree_list (spec, tmpl);
1292 /* Print the list of candidate FNS in an error message. */
1295 print_candidates (tree fns)
1299 const char *str = "candidates are:";
1301 for (fn = fns; fn != NULL_TREE; fn = TREE_CHAIN (fn))
1305 for (f = TREE_VALUE (fn); f; f = OVL_NEXT (f))
1306 error ("%s %+#D", str, OVL_CURRENT (f));
1311 /* Returns the template (one of the functions given by TEMPLATE_ID)
1312 which can be specialized to match the indicated DECL with the
1313 explicit template args given in TEMPLATE_ID. The DECL may be
1314 NULL_TREE if none is available. In that case, the functions in
1315 TEMPLATE_ID are non-members.
1317 If NEED_MEMBER_TEMPLATE is nonzero the function is known to be a
1318 specialization of a member template.
1320 The TEMPLATE_COUNT is the number of references to qualifying
1321 template classes that appeared in the name of the function. See
1322 check_explicit_specialization for a more accurate description.
1324 The template args (those explicitly specified and those deduced)
1325 are output in a newly created vector *TARGS_OUT.
1327 If it is impossible to determine the result, an error message is
1328 issued. The error_mark_node is returned to indicate failure. */
1331 determine_specialization (tree template_id,
1334 int need_member_template,
1339 tree explicit_targs;
1340 tree candidates = NULL_TREE;
1341 tree templates = NULL_TREE;
1343 struct cp_binding_level *b;
1345 *targs_out = NULL_TREE;
1347 if (template_id == error_mark_node)
1348 return error_mark_node;
1350 fns = TREE_OPERAND (template_id, 0);
1351 explicit_targs = TREE_OPERAND (template_id, 1);
1353 if (fns == error_mark_node)
1354 return error_mark_node;
1356 /* Check for baselinks. */
1357 if (BASELINK_P (fns))
1358 fns = BASELINK_FUNCTIONS (fns);
1360 if (!is_overloaded_fn (fns))
1362 error ("%qD is not a function template", fns);
1363 return error_mark_node;
1366 /* Count the number of template headers specified for this
1369 for (b = current_binding_level;
1370 b->kind == sk_template_parms;
1374 for (; fns; fns = OVL_NEXT (fns))
1376 tree fn = OVL_CURRENT (fns);
1378 if (TREE_CODE (fn) == TEMPLATE_DECL)
1380 tree decl_arg_types;
1383 /* DECL might be a specialization of FN. */
1385 /* Adjust the type of DECL in case FN is a static member. */
1386 decl_arg_types = TYPE_ARG_TYPES (TREE_TYPE (decl));
1387 if (DECL_STATIC_FUNCTION_P (fn)
1388 && DECL_NONSTATIC_MEMBER_FUNCTION_P (decl))
1389 decl_arg_types = TREE_CHAIN (decl_arg_types);
1391 /* Check that the number of function parameters matches.
1393 template <class T> void f(int i = 0);
1394 template <> void f<int>();
1395 The specialization f<int> is invalid but is not caught
1396 by get_bindings below. */
1398 fn_arg_types = TYPE_ARG_TYPES (TREE_TYPE (fn));
1399 if (list_length (fn_arg_types) != list_length (decl_arg_types))
1402 /* For a non-static member function, we need to make sure that
1403 the const qualification is the same. This can be done by
1404 checking the 'this' in the argument list. */
1405 if (DECL_NONSTATIC_MEMBER_FUNCTION_P (fn)
1406 && !same_type_p (TREE_VALUE (fn_arg_types),
1407 TREE_VALUE (decl_arg_types)))
1410 /* In case of explicit specialization, we need to check if
1411 the number of template headers appearing in the specialization
1412 is correct. This is usually done in check_explicit_specialization,
1413 but the check done there cannot be exhaustive when specializing
1414 member functions. Consider the following code:
1416 template <> void A<int>::f(int);
1417 template <> template <> void A<int>::f(int);
1419 Assuming that A<int> is not itself an explicit specialization
1420 already, the first line specializes "f" which is a non-template
1421 member function, whilst the second line specializes "f" which
1422 is a template member function. So both lines are syntactically
1423 correct, and check_explicit_specialization does not reject
1426 Here, we can do better, as we are matching the specialization
1427 against the declarations. We count the number of template
1428 headers, and we check if they match TEMPLATE_COUNT + 1
1429 (TEMPLATE_COUNT is the number of qualifying template classes,
1430 plus there must be another header for the member template
1433 Notice that if header_count is zero, this is not a
1434 specialization but rather a template instantiation, so there
1435 is no check we can perform here. */
1436 if (header_count && header_count != template_count + 1)
1439 /* Check that the number of template arguments at the
1440 innermost level for DECL is the same as for FN. */
1441 if (current_binding_level->kind == sk_template_parms
1442 && !current_binding_level->explicit_spec_p
1443 && (TREE_VEC_LENGTH (DECL_INNERMOST_TEMPLATE_PARMS (fn))
1444 != TREE_VEC_LENGTH (TREE_VALUE (current_template_parms))))
1447 /* See whether this function might be a specialization of this
1449 targs = get_bindings (fn, decl, explicit_targs, /*check_ret=*/true);
1452 /* We cannot deduce template arguments that when used to
1453 specialize TMPL will produce DECL. */
1456 /* Save this template, and the arguments deduced. */
1457 templates = tree_cons (targs, fn, templates);
1459 else if (need_member_template)
1460 /* FN is an ordinary member function, and we need a
1461 specialization of a member template. */
1463 else if (TREE_CODE (fn) != FUNCTION_DECL)
1464 /* We can get IDENTIFIER_NODEs here in certain erroneous
1467 else if (!DECL_FUNCTION_MEMBER_P (fn))
1468 /* This is just an ordinary non-member function. Nothing can
1469 be a specialization of that. */
1471 else if (DECL_ARTIFICIAL (fn))
1472 /* Cannot specialize functions that are created implicitly. */
1476 tree decl_arg_types;
1478 /* This is an ordinary member function. However, since
1479 we're here, we can assume it's enclosing class is a
1480 template class. For example,
1482 template <typename T> struct S { void f(); };
1483 template <> void S<int>::f() {}
1485 Here, S<int>::f is a non-template, but S<int> is a
1486 template class. If FN has the same type as DECL, we
1487 might be in business. */
1489 if (!DECL_TEMPLATE_INFO (fn))
1490 /* Its enclosing class is an explicit specialization
1491 of a template class. This is not a candidate. */
1494 if (!same_type_p (TREE_TYPE (TREE_TYPE (decl)),
1495 TREE_TYPE (TREE_TYPE (fn))))
1496 /* The return types differ. */
1499 /* Adjust the type of DECL in case FN is a static member. */
1500 decl_arg_types = TYPE_ARG_TYPES (TREE_TYPE (decl));
1501 if (DECL_STATIC_FUNCTION_P (fn)
1502 && DECL_NONSTATIC_MEMBER_FUNCTION_P (decl))
1503 decl_arg_types = TREE_CHAIN (decl_arg_types);
1505 if (compparms (TYPE_ARG_TYPES (TREE_TYPE (fn)),
1508 candidates = tree_cons (NULL_TREE, fn, candidates);
1512 if (templates && TREE_CHAIN (templates))
1518 It is possible for a specialization with a given function
1519 signature to be instantiated from more than one function
1520 template. In such cases, explicit specification of the
1521 template arguments must be used to uniquely identify the
1522 function template specialization being specialized.
1524 Note that here, there's no suggestion that we're supposed to
1525 determine which of the candidate templates is most
1526 specialized. However, we, also have:
1530 Partial ordering of overloaded function template
1531 declarations is used in the following contexts to select
1532 the function template to which a function template
1533 specialization refers:
1535 -- when an explicit specialization refers to a function
1538 So, we do use the partial ordering rules, at least for now.
1539 This extension can only serve to make invalid programs valid,
1540 so it's safe. And, there is strong anecdotal evidence that
1541 the committee intended the partial ordering rules to apply;
1542 the EDG front-end has that behavior, and John Spicer claims
1543 that the committee simply forgot to delete the wording in
1544 [temp.expl.spec]. */
1545 tree tmpl = most_specialized (templates, decl, explicit_targs);
1546 if (tmpl && tmpl != error_mark_node)
1548 targs = get_bindings (tmpl, decl, explicit_targs, /*check_ret=*/true);
1549 templates = tree_cons (targs, tmpl, NULL_TREE);
1553 if (templates == NULL_TREE && candidates == NULL_TREE)
1555 error ("template-id %qD for %q+D does not match any template "
1556 "declaration", template_id, decl);
1557 return error_mark_node;
1559 else if ((templates && TREE_CHAIN (templates))
1560 || (candidates && TREE_CHAIN (candidates))
1561 || (templates && candidates))
1563 error ("ambiguous template specialization %qD for %q+D",
1565 chainon (candidates, templates);
1566 print_candidates (candidates);
1567 return error_mark_node;
1570 /* We have one, and exactly one, match. */
1573 /* It was a specialization of an ordinary member function in a
1575 *targs_out = copy_node (DECL_TI_ARGS (TREE_VALUE (candidates)));
1576 return DECL_TI_TEMPLATE (TREE_VALUE (candidates));
1579 /* It was a specialization of a template. */
1580 targs = DECL_TI_ARGS (DECL_TEMPLATE_RESULT (TREE_VALUE (templates)));
1581 if (TMPL_ARGS_HAVE_MULTIPLE_LEVELS (targs))
1583 *targs_out = copy_node (targs);
1584 SET_TMPL_ARGS_LEVEL (*targs_out,
1585 TMPL_ARGS_DEPTH (*targs_out),
1586 TREE_PURPOSE (templates));
1589 *targs_out = TREE_PURPOSE (templates);
1590 return TREE_VALUE (templates);
1593 /* Returns a chain of parameter types, exactly like the SPEC_TYPES,
1594 but with the default argument values filled in from those in the
1598 copy_default_args_to_explicit_spec_1 (tree spec_types,
1601 tree new_spec_types;
1606 if (spec_types == void_list_node)
1607 return void_list_node;
1609 /* Substitute into the rest of the list. */
1611 copy_default_args_to_explicit_spec_1 (TREE_CHAIN (spec_types),
1612 TREE_CHAIN (tmpl_types));
1614 /* Add the default argument for this parameter. */
1615 return hash_tree_cons (TREE_PURPOSE (tmpl_types),
1616 TREE_VALUE (spec_types),
1620 /* DECL is an explicit specialization. Replicate default arguments
1621 from the template it specializes. (That way, code like:
1623 template <class T> void f(T = 3);
1624 template <> void f(double);
1627 works, as required.) An alternative approach would be to look up
1628 the correct default arguments at the call-site, but this approach
1629 is consistent with how implicit instantiations are handled. */
1632 copy_default_args_to_explicit_spec (tree decl)
1637 tree new_spec_types;
1641 tree object_type = NULL_TREE;
1642 tree in_charge = NULL_TREE;
1643 tree vtt = NULL_TREE;
1645 /* See if there's anything we need to do. */
1646 tmpl = DECL_TI_TEMPLATE (decl);
1647 tmpl_types = TYPE_ARG_TYPES (TREE_TYPE (DECL_TEMPLATE_RESULT (tmpl)));
1648 for (t = tmpl_types; t; t = TREE_CHAIN (t))
1649 if (TREE_PURPOSE (t))
1654 old_type = TREE_TYPE (decl);
1655 spec_types = TYPE_ARG_TYPES (old_type);
1657 if (DECL_NONSTATIC_MEMBER_FUNCTION_P (decl))
1659 /* Remove the this pointer, but remember the object's type for
1661 object_type = TREE_TYPE (TREE_VALUE (spec_types));
1662 spec_types = TREE_CHAIN (spec_types);
1663 tmpl_types = TREE_CHAIN (tmpl_types);
1665 if (DECL_HAS_IN_CHARGE_PARM_P (decl))
1667 /* DECL may contain more parameters than TMPL due to the extra
1668 in-charge parameter in constructors and destructors. */
1669 in_charge = spec_types;
1670 spec_types = TREE_CHAIN (spec_types);
1672 if (DECL_HAS_VTT_PARM_P (decl))
1675 spec_types = TREE_CHAIN (spec_types);
1679 /* Compute the merged default arguments. */
1681 copy_default_args_to_explicit_spec_1 (spec_types, tmpl_types);
1683 /* Compute the new FUNCTION_TYPE. */
1687 new_spec_types = hash_tree_cons (TREE_PURPOSE (vtt),
1692 /* Put the in-charge parameter back. */
1693 new_spec_types = hash_tree_cons (TREE_PURPOSE (in_charge),
1694 TREE_VALUE (in_charge),
1697 new_type = build_method_type_directly (object_type,
1698 TREE_TYPE (old_type),
1702 new_type = build_function_type (TREE_TYPE (old_type),
1704 new_type = cp_build_type_attribute_variant (new_type,
1705 TYPE_ATTRIBUTES (old_type));
1706 new_type = build_exception_variant (new_type,
1707 TYPE_RAISES_EXCEPTIONS (old_type));
1708 TREE_TYPE (decl) = new_type;
1711 /* Check to see if the function just declared, as indicated in
1712 DECLARATOR, and in DECL, is a specialization of a function
1713 template. We may also discover that the declaration is an explicit
1714 instantiation at this point.
1716 Returns DECL, or an equivalent declaration that should be used
1717 instead if all goes well. Issues an error message if something is
1718 amiss. Returns error_mark_node if the error is not easily
1721 FLAGS is a bitmask consisting of the following flags:
1723 2: The function has a definition.
1724 4: The function is a friend.
1726 The TEMPLATE_COUNT is the number of references to qualifying
1727 template classes that appeared in the name of the function. For
1730 template <class T> struct S { void f(); };
1733 the TEMPLATE_COUNT would be 1. However, explicitly specialized
1734 classes are not counted in the TEMPLATE_COUNT, so that in
1736 template <class T> struct S {};
1737 template <> struct S<int> { void f(); }
1738 template <> void S<int>::f();
1740 the TEMPLATE_COUNT would be 0. (Note that this declaration is
1741 invalid; there should be no template <>.)
1743 If the function is a specialization, it is marked as such via
1744 DECL_TEMPLATE_SPECIALIZATION. Furthermore, its DECL_TEMPLATE_INFO
1745 is set up correctly, and it is added to the list of specializations
1746 for that template. */
1749 check_explicit_specialization (tree declarator,
1754 int have_def = flags & 2;
1755 int is_friend = flags & 4;
1756 int specialization = 0;
1757 int explicit_instantiation = 0;
1758 int member_specialization = 0;
1759 tree ctype = DECL_CLASS_CONTEXT (decl);
1760 tree dname = DECL_NAME (decl);
1765 if (!processing_specialization)
1768 tsk = tsk_excessive_parms;
1771 tsk = current_tmpl_spec_kind (template_count);
1776 if (processing_specialization)
1779 SET_DECL_TEMPLATE_SPECIALIZATION (decl);
1781 else if (TREE_CODE (declarator) == TEMPLATE_ID_EXPR)
1784 /* This could be something like:
1786 template <class T> void f(T);
1787 class S { friend void f<>(int); } */
1791 /* This case handles bogus declarations like template <>
1792 template <class T> void f<int>(); */
1794 error ("template-id %qD in declaration of primary template",
1801 case tsk_invalid_member_spec:
1802 /* The error has already been reported in
1803 check_specialization_scope. */
1804 return error_mark_node;
1806 case tsk_invalid_expl_inst:
1807 error ("template parameter list used in explicit instantiation");
1813 error ("definition provided for explicit instantiation");
1815 explicit_instantiation = 1;
1818 case tsk_excessive_parms:
1819 case tsk_insufficient_parms:
1820 if (tsk == tsk_excessive_parms)
1821 error ("too many template parameter lists in declaration of %qD",
1823 else if (template_header_count)
1824 error("too few template parameter lists in declaration of %qD", decl);
1826 error("explicit specialization of %qD must be introduced by "
1827 "%<template <>%>", decl);
1831 SET_DECL_TEMPLATE_SPECIALIZATION (decl);
1833 member_specialization = 1;
1839 if (TREE_CODE (declarator) == TEMPLATE_ID_EXPR)
1841 /* This case handles bogus declarations like template <>
1842 template <class T> void f<int>(); */
1844 if (uses_template_parms (declarator))
1845 error ("function template partial specialization %qD "
1846 "is not allowed", declarator);
1848 error ("template-id %qD in declaration of primary template",
1853 if (ctype && CLASSTYPE_TEMPLATE_INSTANTIATION (ctype))
1854 /* This is a specialization of a member template, without
1855 specialization the containing class. Something like:
1857 template <class T> struct S {
1858 template <class U> void f (U);
1860 template <> template <class U> void S<int>::f(U) {}
1862 That's a specialization -- but of the entire template. */
1870 if (specialization || member_specialization)
1872 tree t = TYPE_ARG_TYPES (TREE_TYPE (decl));
1873 for (; t; t = TREE_CHAIN (t))
1874 if (TREE_PURPOSE (t))
1877 ("default argument specified in explicit specialization");
1880 if (current_lang_name == lang_name_c)
1881 error ("template specialization with C linkage");
1884 if (specialization || member_specialization || explicit_instantiation)
1886 tree tmpl = NULL_TREE;
1887 tree targs = NULL_TREE;
1889 /* Make sure that the declarator is a TEMPLATE_ID_EXPR. */
1890 if (TREE_CODE (declarator) != TEMPLATE_ID_EXPR)
1894 gcc_assert (TREE_CODE (declarator) == IDENTIFIER_NODE);
1899 /* If there is no class context, the explicit instantiation
1900 must be at namespace scope. */
1901 gcc_assert (DECL_NAMESPACE_SCOPE_P (decl));
1903 /* Find the namespace binding, using the declaration
1905 fns = namespace_binding (dname, CP_DECL_CONTEXT (decl));
1906 if (!fns || !is_overloaded_fn (fns))
1908 error ("%qD is not a template function", dname);
1909 fns = error_mark_node;
1913 declarator = lookup_template_function (fns, NULL_TREE);
1916 if (declarator == error_mark_node)
1917 return error_mark_node;
1919 if (ctype != NULL_TREE && TYPE_BEING_DEFINED (ctype))
1921 if (!explicit_instantiation)
1922 /* A specialization in class scope. This is invalid,
1923 but the error will already have been flagged by
1924 check_specialization_scope. */
1925 return error_mark_node;
1928 /* It's not valid to write an explicit instantiation in
1931 class C { template void f(); }
1933 This case is caught by the parser. However, on
1936 template class C { void f(); };
1938 (which is invalid) we can get here. The error will be
1945 else if (ctype != NULL_TREE
1946 && (TREE_CODE (TREE_OPERAND (declarator, 0)) ==
1949 /* Find the list of functions in ctype that have the same
1950 name as the declared function. */
1951 tree name = TREE_OPERAND (declarator, 0);
1952 tree fns = NULL_TREE;
1955 if (constructor_name_p (name, ctype))
1957 int is_constructor = DECL_CONSTRUCTOR_P (decl);
1959 if (is_constructor ? !TYPE_HAS_CONSTRUCTOR (ctype)
1960 : !CLASSTYPE_DESTRUCTORS (ctype))
1962 /* From [temp.expl.spec]:
1964 If such an explicit specialization for the member
1965 of a class template names an implicitly-declared
1966 special member function (clause _special_), the
1967 program is ill-formed.
1969 Similar language is found in [temp.explicit]. */
1970 error ("specialization of implicitly-declared special member function");
1971 return error_mark_node;
1974 name = is_constructor ? ctor_identifier : dtor_identifier;
1977 if (!DECL_CONV_FN_P (decl))
1979 idx = lookup_fnfields_1 (ctype, name);
1981 fns = VEC_index (tree, CLASSTYPE_METHOD_VEC (ctype), idx);
1985 VEC(tree,gc) *methods;
1988 /* For a type-conversion operator, we cannot do a
1989 name-based lookup. We might be looking for `operator
1990 int' which will be a specialization of `operator T'.
1991 So, we find *all* the conversion operators, and then
1992 select from them. */
1995 methods = CLASSTYPE_METHOD_VEC (ctype);
1997 for (idx = CLASSTYPE_FIRST_CONVERSION_SLOT;
1998 VEC_iterate (tree, methods, idx, ovl);
2001 if (!DECL_CONV_FN_P (OVL_CURRENT (ovl)))
2002 /* There are no more conversion functions. */
2005 /* Glue all these conversion functions together
2006 with those we already have. */
2007 for (; ovl; ovl = OVL_NEXT (ovl))
2008 fns = ovl_cons (OVL_CURRENT (ovl), fns);
2012 if (fns == NULL_TREE)
2014 error ("no member function %qD declared in %qT", name, ctype);
2015 return error_mark_node;
2018 TREE_OPERAND (declarator, 0) = fns;
2021 /* Figure out what exactly is being specialized at this point.
2022 Note that for an explicit instantiation, even one for a
2023 member function, we cannot tell apriori whether the
2024 instantiation is for a member template, or just a member
2025 function of a template class. Even if a member template is
2026 being instantiated, the member template arguments may be
2027 elided if they can be deduced from the rest of the
2029 tmpl = determine_specialization (declarator, decl,
2031 member_specialization,
2034 if (!tmpl || tmpl == error_mark_node)
2035 /* We couldn't figure out what this declaration was
2037 return error_mark_node;
2040 tree gen_tmpl = most_general_template (tmpl);
2042 if (explicit_instantiation)
2044 /* We don't set DECL_EXPLICIT_INSTANTIATION here; that
2045 is done by do_decl_instantiation later. */
2047 int arg_depth = TMPL_ARGS_DEPTH (targs);
2048 int parm_depth = TMPL_PARMS_DEPTH (DECL_TEMPLATE_PARMS (tmpl));
2050 if (arg_depth > parm_depth)
2052 /* If TMPL is not the most general template (for
2053 example, if TMPL is a friend template that is
2054 injected into namespace scope), then there will
2055 be too many levels of TARGS. Remove some of them
2060 new_targs = make_tree_vec (parm_depth);
2061 for (i = arg_depth - parm_depth; i < arg_depth; ++i)
2062 TREE_VEC_ELT (new_targs, i - (arg_depth - parm_depth))
2063 = TREE_VEC_ELT (targs, i);
2067 return instantiate_template (tmpl, targs, tf_error);
2070 /* If we thought that the DECL was a member function, but it
2071 turns out to be specializing a static member function,
2072 make DECL a static member function as well. */
2073 if (DECL_STATIC_FUNCTION_P (tmpl)
2074 && DECL_NONSTATIC_MEMBER_FUNCTION_P (decl))
2075 revert_static_member_fn (decl);
2077 /* If this is a specialization of a member template of a
2078 template class. In we want to return the TEMPLATE_DECL,
2079 not the specialization of it. */
2080 if (tsk == tsk_template)
2082 SET_DECL_TEMPLATE_SPECIALIZATION (tmpl);
2083 DECL_INITIAL (DECL_TEMPLATE_RESULT (tmpl)) = NULL_TREE;
2086 DECL_SOURCE_LOCATION (tmpl) = DECL_SOURCE_LOCATION (decl);
2087 DECL_SOURCE_LOCATION (DECL_TEMPLATE_RESULT (tmpl))
2088 = DECL_SOURCE_LOCATION (decl);
2089 /* We want to use the argument list specified in the
2090 definition, not in the original declaration. */
2091 DECL_ARGUMENTS (DECL_TEMPLATE_RESULT (tmpl))
2092 = DECL_ARGUMENTS (decl);
2097 /* Set up the DECL_TEMPLATE_INFO for DECL. */
2098 DECL_TEMPLATE_INFO (decl) = tree_cons (tmpl, targs, NULL_TREE);
2100 /* Inherit default function arguments from the template
2101 DECL is specializing. */
2102 copy_default_args_to_explicit_spec (decl);
2104 /* This specialization has the same protection as the
2105 template it specializes. */
2106 TREE_PRIVATE (decl) = TREE_PRIVATE (gen_tmpl);
2107 TREE_PROTECTED (decl) = TREE_PROTECTED (gen_tmpl);
2108 /* The specialization has the same visibility as the
2109 template it specializes. */
2110 if (DECL_VISIBILITY_SPECIFIED (gen_tmpl))
2112 DECL_VISIBILITY_SPECIFIED (decl) = 1;
2113 DECL_VISIBILITY (decl) = DECL_VISIBILITY (gen_tmpl);
2115 /* If DECL is a friend declaration, declared using an
2116 unqualified name, the namespace associated with DECL may
2117 have been set incorrectly. For example, in:
2119 template <typename T> void f(T);
2121 struct S { friend void f<int>(int); }
2124 we will have set the DECL_CONTEXT for the friend
2125 declaration to N, rather than to the global namespace. */
2126 if (DECL_NAMESPACE_SCOPE_P (decl))
2127 DECL_CONTEXT (decl) = DECL_CONTEXT (tmpl);
2129 if (is_friend && !have_def)
2130 /* This is not really a declaration of a specialization.
2131 It's just the name of an instantiation. But, it's not
2132 a request for an instantiation, either. */
2133 SET_DECL_IMPLICIT_INSTANTIATION (decl);
2134 else if (DECL_CONSTRUCTOR_P (decl) || DECL_DESTRUCTOR_P (decl))
2135 /* This is indeed a specialization. In case of constructors
2136 and destructors, we need in-charge and not-in-charge
2137 versions in V3 ABI. */
2138 clone_function_decl (decl, /*update_method_vec_p=*/0);
2140 /* Register this specialization so that we can find it
2142 decl = register_specialization (decl, gen_tmpl, targs, is_friend);
2149 /* Returns 1 iff PARMS1 and PARMS2 are identical sets of template
2150 parameters. These are represented in the same format used for
2151 DECL_TEMPLATE_PARMS. */
2154 comp_template_parms (tree parms1, tree parms2)
2159 if (parms1 == parms2)
2162 for (p1 = parms1, p2 = parms2;
2163 p1 != NULL_TREE && p2 != NULL_TREE;
2164 p1 = TREE_CHAIN (p1), p2 = TREE_CHAIN (p2))
2166 tree t1 = TREE_VALUE (p1);
2167 tree t2 = TREE_VALUE (p2);
2170 gcc_assert (TREE_CODE (t1) == TREE_VEC);
2171 gcc_assert (TREE_CODE (t2) == TREE_VEC);
2173 if (TREE_VEC_LENGTH (t1) != TREE_VEC_LENGTH (t2))
2176 for (i = 0; i < TREE_VEC_LENGTH (t2); ++i)
2178 tree parm1 = TREE_VALUE (TREE_VEC_ELT (t1, i));
2179 tree parm2 = TREE_VALUE (TREE_VEC_ELT (t2, i));
2181 if (TREE_CODE (parm1) != TREE_CODE (parm2))
2184 if (TREE_CODE (parm1) == TEMPLATE_TYPE_PARM)
2186 else if (!same_type_p (TREE_TYPE (parm1), TREE_TYPE (parm2)))
2191 if ((p1 != NULL_TREE) != (p2 != NULL_TREE))
2192 /* One set of parameters has more parameters lists than the
2199 /* Complain if DECL shadows a template parameter.
2201 [temp.local]: A template-parameter shall not be redeclared within its
2202 scope (including nested scopes). */
2205 check_template_shadow (tree decl)
2209 /* If we're not in a template, we can't possibly shadow a template
2211 if (!current_template_parms)
2214 /* Figure out what we're shadowing. */
2215 if (TREE_CODE (decl) == OVERLOAD)
2216 decl = OVL_CURRENT (decl);
2217 olddecl = innermost_non_namespace_value (DECL_NAME (decl));
2219 /* If there's no previous binding for this name, we're not shadowing
2220 anything, let alone a template parameter. */
2224 /* If we're not shadowing a template parameter, we're done. Note
2225 that OLDDECL might be an OVERLOAD (or perhaps even an
2226 ERROR_MARK), so we can't just blithely assume it to be a _DECL
2228 if (!DECL_P (olddecl) || !DECL_TEMPLATE_PARM_P (olddecl))
2231 /* We check for decl != olddecl to avoid bogus errors for using a
2232 name inside a class. We check TPFI to avoid duplicate errors for
2233 inline member templates. */
2235 || TEMPLATE_PARMS_FOR_INLINE (current_template_parms))
2238 error ("declaration of %q+#D", decl);
2239 error (" shadows template parm %q+#D", olddecl);
2242 /* Return a new TEMPLATE_PARM_INDEX with the indicated INDEX, LEVEL,
2243 ORIG_LEVEL, DECL, and TYPE. */
2246 build_template_parm_index (int index,
2252 tree t = make_node (TEMPLATE_PARM_INDEX);
2253 TEMPLATE_PARM_IDX (t) = index;
2254 TEMPLATE_PARM_LEVEL (t) = level;
2255 TEMPLATE_PARM_ORIG_LEVEL (t) = orig_level;
2256 TEMPLATE_PARM_DECL (t) = decl;
2257 TREE_TYPE (t) = type;
2258 TREE_CONSTANT (t) = TREE_CONSTANT (decl);
2259 TREE_INVARIANT (t) = TREE_INVARIANT (decl);
2260 TREE_READONLY (t) = TREE_READONLY (decl);
2265 /* Return a TEMPLATE_PARM_INDEX, similar to INDEX, but whose
2266 TEMPLATE_PARM_LEVEL has been decreased by LEVELS. If such a
2267 TEMPLATE_PARM_INDEX already exists, it is returned; otherwise, a
2268 new one is created. */
2271 reduce_template_parm_level (tree index, tree type, int levels)
2273 if (TEMPLATE_PARM_DESCENDANTS (index) == NULL_TREE
2274 || (TEMPLATE_PARM_LEVEL (TEMPLATE_PARM_DESCENDANTS (index))
2275 != TEMPLATE_PARM_LEVEL (index) - levels))
2277 tree orig_decl = TEMPLATE_PARM_DECL (index);
2280 decl = build_decl (TREE_CODE (orig_decl), DECL_NAME (orig_decl), type);
2281 TREE_CONSTANT (decl) = TREE_CONSTANT (orig_decl);
2282 TREE_INVARIANT (decl) = TREE_INVARIANT (orig_decl);
2283 TREE_READONLY (decl) = TREE_READONLY (orig_decl);
2284 DECL_ARTIFICIAL (decl) = 1;
2285 SET_DECL_TEMPLATE_PARM_P (decl);
2287 t = build_template_parm_index (TEMPLATE_PARM_IDX (index),
2288 TEMPLATE_PARM_LEVEL (index) - levels,
2289 TEMPLATE_PARM_ORIG_LEVEL (index),
2291 TEMPLATE_PARM_DESCENDANTS (index) = t;
2293 /* Template template parameters need this. */
2294 if (TREE_CODE (decl) != CONST_DECL)
2295 DECL_TEMPLATE_PARMS (decl)
2296 = DECL_TEMPLATE_PARMS (TEMPLATE_PARM_DECL (index));
2299 return TEMPLATE_PARM_DESCENDANTS (index);
2302 /* Process information from new template parameter NEXT and append it to the
2303 LIST being built. This new parameter is a non-type parameter iff
2304 IS_NON_TYPE is true. */
2307 process_template_parm (tree list, tree next, bool is_non_type)
2315 gcc_assert (TREE_CODE (parm) == TREE_LIST);
2316 defval = TREE_PURPOSE (parm);
2320 tree p = TREE_VALUE (tree_last (list));
2322 if (TREE_CODE (p) == TYPE_DECL || TREE_CODE (p) == TEMPLATE_DECL)
2323 idx = TEMPLATE_TYPE_IDX (TREE_TYPE (p));
2325 idx = TEMPLATE_PARM_IDX (DECL_INITIAL (p));
2333 parm = TREE_VALUE (parm);
2335 SET_DECL_TEMPLATE_PARM_P (parm);
2339 The top-level cv-qualifiers on the template-parameter are
2340 ignored when determining its type. */
2341 TREE_TYPE (parm) = TYPE_MAIN_VARIANT (TREE_TYPE (parm));
2343 /* A template parameter is not modifiable. */
2344 TREE_CONSTANT (parm) = 1;
2345 TREE_INVARIANT (parm) = 1;
2346 TREE_READONLY (parm) = 1;
2347 if (invalid_nontype_parm_type_p (TREE_TYPE (parm), 1))
2348 TREE_TYPE (parm) = void_type_node;
2349 decl = build_decl (CONST_DECL, DECL_NAME (parm), TREE_TYPE (parm));
2350 TREE_CONSTANT (decl) = 1;
2351 TREE_INVARIANT (decl) = 1;
2352 TREE_READONLY (decl) = 1;
2353 DECL_INITIAL (parm) = DECL_INITIAL (decl)
2354 = build_template_parm_index (idx, processing_template_decl,
2355 processing_template_decl,
2356 decl, TREE_TYPE (parm));
2361 parm = TREE_VALUE (TREE_VALUE (parm));
2363 if (parm && TREE_CODE (parm) == TEMPLATE_DECL)
2365 t = make_aggr_type (TEMPLATE_TEMPLATE_PARM);
2366 /* This is for distinguishing between real templates and template
2367 template parameters */
2368 TREE_TYPE (parm) = t;
2369 TREE_TYPE (DECL_TEMPLATE_RESULT (parm)) = t;
2374 t = make_aggr_type (TEMPLATE_TYPE_PARM);
2375 /* parm is either IDENTIFIER_NODE or NULL_TREE. */
2376 decl = build_decl (TYPE_DECL, parm, t);
2379 TYPE_NAME (t) = decl;
2380 TYPE_STUB_DECL (t) = decl;
2382 TEMPLATE_TYPE_PARM_INDEX (t)
2383 = build_template_parm_index (idx, processing_template_decl,
2384 processing_template_decl,
2385 decl, TREE_TYPE (parm));
2387 DECL_ARTIFICIAL (decl) = 1;
2388 SET_DECL_TEMPLATE_PARM_P (decl);
2390 parm = build_tree_list (defval, parm);
2391 return chainon (list, parm);
2394 /* The end of a template parameter list has been reached. Process the
2395 tree list into a parameter vector, converting each parameter into a more
2396 useful form. Type parameters are saved as IDENTIFIER_NODEs, and others
2400 end_template_parm_list (tree parms)
2404 tree saved_parmlist = make_tree_vec (list_length (parms));
2406 current_template_parms
2407 = tree_cons (size_int (processing_template_decl),
2408 saved_parmlist, current_template_parms);
2410 for (parm = parms, nparms = 0; parm; parm = next, nparms++)
2412 next = TREE_CHAIN (parm);
2413 TREE_VEC_ELT (saved_parmlist, nparms) = parm;
2414 TREE_CHAIN (parm) = NULL_TREE;
2417 --processing_template_parmlist;
2419 return saved_parmlist;
2422 /* end_template_decl is called after a template declaration is seen. */
2425 end_template_decl (void)
2427 reset_specialization ();
2429 if (! processing_template_decl)
2432 /* This matches the pushlevel in begin_template_parm_list. */
2435 --processing_template_decl;
2436 current_template_parms = TREE_CHAIN (current_template_parms);
2439 /* Given a template argument vector containing the template PARMS.
2440 The innermost PARMS are given first. */
2443 current_template_args (void)
2446 tree args = NULL_TREE;
2447 int length = TMPL_PARMS_DEPTH (current_template_parms);
2450 /* If there is only one level of template parameters, we do not
2451 create a TREE_VEC of TREE_VECs. Instead, we return a single
2452 TREE_VEC containing the arguments. */
2454 args = make_tree_vec (length);
2456 for (header = current_template_parms; header; header = TREE_CHAIN (header))
2458 tree a = copy_node (TREE_VALUE (header));
2461 TREE_TYPE (a) = NULL_TREE;
2462 for (i = TREE_VEC_LENGTH (a) - 1; i >= 0; --i)
2464 tree t = TREE_VEC_ELT (a, i);
2466 /* T will be a list if we are called from within a
2467 begin/end_template_parm_list pair, but a vector directly
2468 if within a begin/end_member_template_processing pair. */
2469 if (TREE_CODE (t) == TREE_LIST)
2473 if (TREE_CODE (t) == TYPE_DECL
2474 || TREE_CODE (t) == TEMPLATE_DECL)
2477 t = DECL_INITIAL (t);
2478 TREE_VEC_ELT (a, i) = t;
2483 TREE_VEC_ELT (args, --l) = a;
2491 /* Return a TEMPLATE_DECL corresponding to DECL, using the indicated
2492 template PARMS. If MEMBER_TEMPLATE_P is true, the new template is
2493 a member template. Used by push_template_decl below. */
2496 build_template_decl (tree decl, tree parms, bool member_template_p)
2498 tree tmpl = build_lang_decl (TEMPLATE_DECL, DECL_NAME (decl), NULL_TREE);
2499 DECL_TEMPLATE_PARMS (tmpl) = parms;
2500 DECL_CONTEXT (tmpl) = DECL_CONTEXT (decl);
2501 DECL_MEMBER_TEMPLATE_P (tmpl) = member_template_p;
2502 if (DECL_LANG_SPECIFIC (decl))
2504 DECL_STATIC_FUNCTION_P (tmpl) = DECL_STATIC_FUNCTION_P (decl);
2505 DECL_CONSTRUCTOR_P (tmpl) = DECL_CONSTRUCTOR_P (decl);
2506 DECL_DESTRUCTOR_P (tmpl) = DECL_DESTRUCTOR_P (decl);
2507 DECL_NONCONVERTING_P (tmpl) = DECL_NONCONVERTING_P (decl);
2508 DECL_ASSIGNMENT_OPERATOR_P (tmpl) = DECL_ASSIGNMENT_OPERATOR_P (decl);
2509 if (DECL_OVERLOADED_OPERATOR_P (decl))
2510 SET_OVERLOADED_OPERATOR_CODE (tmpl,
2511 DECL_OVERLOADED_OPERATOR_P (decl));
2517 struct template_parm_data
2519 /* The level of the template parameters we are currently
2523 /* The index of the specialization argument we are currently
2527 /* An array whose size is the number of template parameters. The
2528 elements are nonzero if the parameter has been used in any one
2529 of the arguments processed so far. */
2532 /* An array whose size is the number of template arguments. The
2533 elements are nonzero if the argument makes use of template
2534 parameters of this level. */
2535 int* arg_uses_template_parms;
2538 /* Subroutine of push_template_decl used to see if each template
2539 parameter in a partial specialization is used in the explicit
2540 argument list. If T is of the LEVEL given in DATA (which is
2541 treated as a template_parm_data*), then DATA->PARMS is marked
2545 mark_template_parm (tree t, void* data)
2549 struct template_parm_data* tpd = (struct template_parm_data*) data;
2551 if (TREE_CODE (t) == TEMPLATE_PARM_INDEX)
2553 level = TEMPLATE_PARM_LEVEL (t);
2554 idx = TEMPLATE_PARM_IDX (t);
2558 level = TEMPLATE_TYPE_LEVEL (t);
2559 idx = TEMPLATE_TYPE_IDX (t);
2562 if (level == tpd->level)
2564 tpd->parms[idx] = 1;
2565 tpd->arg_uses_template_parms[tpd->current_arg] = 1;
2568 /* Return zero so that for_each_template_parm will continue the
2569 traversal of the tree; we want to mark *every* template parm. */
2573 /* Process the partial specialization DECL. */
2576 process_partial_specialization (tree decl)
2578 tree type = TREE_TYPE (decl);
2579 tree maintmpl = CLASSTYPE_TI_TEMPLATE (type);
2580 tree specargs = CLASSTYPE_TI_ARGS (type);
2581 tree inner_args = INNERMOST_TEMPLATE_ARGS (specargs);
2582 tree inner_parms = INNERMOST_TEMPLATE_PARMS (current_template_parms);
2583 tree main_inner_parms = DECL_INNERMOST_TEMPLATE_PARMS (maintmpl);
2584 int nargs = TREE_VEC_LENGTH (inner_args);
2585 int ntparms = TREE_VEC_LENGTH (inner_parms);
2587 int did_error_intro = 0;
2588 struct template_parm_data tpd;
2589 struct template_parm_data tpd2;
2591 /* We check that each of the template parameters given in the
2592 partial specialization is used in the argument list to the
2593 specialization. For example:
2595 template <class T> struct S;
2596 template <class T> struct S<T*>;
2598 The second declaration is OK because `T*' uses the template
2599 parameter T, whereas
2601 template <class T> struct S<int>;
2603 is no good. Even trickier is:
2614 The S2<T> declaration is actually invalid; it is a
2615 full-specialization. Of course,
2618 struct S2<T (*)(U)>;
2620 or some such would have been OK. */
2621 tpd.level = TMPL_PARMS_DEPTH (current_template_parms);
2622 tpd.parms = alloca (sizeof (int) * ntparms);
2623 memset (tpd.parms, 0, sizeof (int) * ntparms);
2625 tpd.arg_uses_template_parms = alloca (sizeof (int) * nargs);
2626 memset (tpd.arg_uses_template_parms, 0, sizeof (int) * nargs);
2627 for (i = 0; i < nargs; ++i)
2629 tpd.current_arg = i;
2630 for_each_template_parm (TREE_VEC_ELT (inner_args, i),
2631 &mark_template_parm,
2635 for (i = 0; i < ntparms; ++i)
2636 if (tpd.parms[i] == 0)
2638 /* One of the template parms was not used in the
2640 if (!did_error_intro)
2642 error ("template parameters not used in partial specialization:");
2643 did_error_intro = 1;
2646 error (" %qD", TREE_VALUE (TREE_VEC_ELT (inner_parms, i)));
2649 /* [temp.class.spec]
2651 The argument list of the specialization shall not be identical to
2652 the implicit argument list of the primary template. */
2653 if (comp_template_args
2655 INNERMOST_TEMPLATE_ARGS (CLASSTYPE_TI_ARGS (TREE_TYPE
2657 error ("partial specialization %qT does not specialize any template arguments", type);
2659 /* [temp.class.spec]
2661 A partially specialized non-type argument expression shall not
2662 involve template parameters of the partial specialization except
2663 when the argument expression is a simple identifier.
2665 The type of a template parameter corresponding to a specialized
2666 non-type argument shall not be dependent on a parameter of the
2668 gcc_assert (nargs == DECL_NTPARMS (maintmpl));
2670 for (i = 0; i < nargs; ++i)
2672 tree arg = TREE_VEC_ELT (inner_args, i);
2673 if (/* These first two lines are the `non-type' bit. */
2675 && TREE_CODE (arg) != TEMPLATE_DECL
2676 /* This next line is the `argument expression is not just a
2677 simple identifier' condition and also the `specialized
2678 non-type argument' bit. */
2679 && TREE_CODE (arg) != TEMPLATE_PARM_INDEX)
2681 if (tpd.arg_uses_template_parms[i])
2682 error ("template argument %qE involves template parameter(s)", arg);
2685 /* Look at the corresponding template parameter,
2686 marking which template parameters its type depends
2689 TREE_TYPE (TREE_VALUE (TREE_VEC_ELT (main_inner_parms,
2694 /* We haven't yet initialized TPD2. Do so now. */
2695 tpd2.arg_uses_template_parms
2696 = alloca (sizeof (int) * nargs);
2697 /* The number of parameters here is the number in the
2698 main template, which, as checked in the assertion
2700 tpd2.parms = alloca (sizeof (int) * nargs);
2702 TMPL_PARMS_DEPTH (DECL_TEMPLATE_PARMS (maintmpl));
2705 /* Mark the template parameters. But this time, we're
2706 looking for the template parameters of the main
2707 template, not in the specialization. */
2708 tpd2.current_arg = i;
2709 tpd2.arg_uses_template_parms[i] = 0;
2710 memset (tpd2.parms, 0, sizeof (int) * nargs);
2711 for_each_template_parm (type,
2712 &mark_template_parm,
2716 if (tpd2.arg_uses_template_parms [i])
2718 /* The type depended on some template parameters.
2719 If they are fully specialized in the
2720 specialization, that's OK. */
2722 for (j = 0; j < nargs; ++j)
2723 if (tpd2.parms[j] != 0
2724 && tpd.arg_uses_template_parms [j])
2726 error ("type %qT of template argument %qE depends "
2727 "on template parameter(s)",
2737 if (retrieve_specialization (maintmpl, specargs,
2738 /*class_specializations_p=*/true))
2739 /* We've already got this specialization. */
2742 DECL_TEMPLATE_SPECIALIZATIONS (maintmpl)
2743 = tree_cons (inner_args, inner_parms,
2744 DECL_TEMPLATE_SPECIALIZATIONS (maintmpl));
2745 TREE_TYPE (DECL_TEMPLATE_SPECIALIZATIONS (maintmpl)) = type;
2749 /* Check that a template declaration's use of default arguments is not
2750 invalid. Here, PARMS are the template parameters. IS_PRIMARY is
2751 nonzero if DECL is the thing declared by a primary template.
2752 IS_PARTIAL is nonzero if DECL is a partial specialization. */
2755 check_default_tmpl_args (tree decl, tree parms, int is_primary, int is_partial)
2758 int last_level_to_check;
2763 A default template-argument shall not be specified in a
2764 function template declaration or a function template definition, nor
2765 in the template-parameter-list of the definition of a member of a
2768 if (TREE_CODE (CP_DECL_CONTEXT (decl)) == FUNCTION_DECL)
2769 /* You can't have a function template declaration in a local
2770 scope, nor you can you define a member of a class template in a
2774 if (current_class_type
2775 && !TYPE_BEING_DEFINED (current_class_type)
2776 && DECL_LANG_SPECIFIC (decl)
2777 /* If this is either a friend defined in the scope of the class
2778 or a member function. */
2779 && (DECL_FUNCTION_MEMBER_P (decl)
2780 ? same_type_p (DECL_CONTEXT (decl), current_class_type)
2781 : DECL_FRIEND_CONTEXT (decl)
2782 ? same_type_p (DECL_FRIEND_CONTEXT (decl), current_class_type)
2784 /* And, if it was a member function, it really was defined in
2785 the scope of the class. */
2786 && (!DECL_FUNCTION_MEMBER_P (decl)
2787 || DECL_INITIALIZED_IN_CLASS_P (decl)))
2788 /* We already checked these parameters when the template was
2789 declared, so there's no need to do it again now. This function
2790 was defined in class scope, but we're processing it's body now
2791 that the class is complete. */
2796 If a template-parameter has a default template-argument, all
2797 subsequent template-parameters shall have a default
2798 template-argument supplied. */
2799 for (parm_level = parms; parm_level; parm_level = TREE_CHAIN (parm_level))
2801 tree inner_parms = TREE_VALUE (parm_level);
2802 int ntparms = TREE_VEC_LENGTH (inner_parms);
2803 int seen_def_arg_p = 0;
2806 for (i = 0; i < ntparms; ++i)
2808 tree parm = TREE_VEC_ELT (inner_parms, i);
2809 if (TREE_PURPOSE (parm))
2811 else if (seen_def_arg_p)
2813 error ("no default argument for %qD", TREE_VALUE (parm));
2814 /* For better subsequent error-recovery, we indicate that
2815 there should have been a default argument. */
2816 TREE_PURPOSE (parm) = error_mark_node;
2821 if (TREE_CODE (decl) != TYPE_DECL || is_partial || !is_primary)
2822 /* For an ordinary class template, default template arguments are
2823 allowed at the innermost level, e.g.:
2824 template <class T = int>
2826 but, in a partial specialization, they're not allowed even
2827 there, as we have in [temp.class.spec]:
2829 The template parameter list of a specialization shall not
2830 contain default template argument values.
2832 So, for a partial specialization, or for a function template,
2833 we look at all of them. */
2836 /* But, for a primary class template that is not a partial
2837 specialization we look at all template parameters except the
2839 parms = TREE_CHAIN (parms);
2841 /* Figure out what error message to issue. */
2842 if (TREE_CODE (decl) == FUNCTION_DECL)
2843 msg = "default template arguments may not be used in function templates";
2844 else if (is_partial)
2845 msg = "default template arguments may not be used in partial specializations";
2847 msg = "default argument for template parameter for class enclosing %qD";
2849 if (current_class_type && TYPE_BEING_DEFINED (current_class_type))
2850 /* If we're inside a class definition, there's no need to
2851 examine the parameters to the class itself. On the one
2852 hand, they will be checked when the class is defined, and,
2853 on the other, default arguments are valid in things like:
2854 template <class T = double>
2855 struct S { template <class U> void f(U); };
2856 Here the default argument for `S' has no bearing on the
2857 declaration of `f'. */
2858 last_level_to_check = template_class_depth (current_class_type) + 1;
2860 /* Check everything. */
2861 last_level_to_check = 0;
2863 for (parm_level = parms;
2864 parm_level && TMPL_PARMS_DEPTH (parm_level) >= last_level_to_check;
2865 parm_level = TREE_CHAIN (parm_level))
2867 tree inner_parms = TREE_VALUE (parm_level);
2871 ntparms = TREE_VEC_LENGTH (inner_parms);
2872 for (i = 0; i < ntparms; ++i)
2873 if (TREE_PURPOSE (TREE_VEC_ELT (inner_parms, i)))
2881 /* Clear out the default argument so that we are not
2883 TREE_PURPOSE (TREE_VEC_ELT (inner_parms, i)) = NULL_TREE;
2886 /* At this point, if we're still interested in issuing messages,
2887 they must apply to classes surrounding the object declared. */
2889 msg = "default argument for template parameter for class enclosing %qD";
2893 /* Worker for push_template_decl_real, called via
2894 for_each_template_parm. DATA is really an int, indicating the
2895 level of the parameters we are interested in. If T is a template
2896 parameter of that level, return nonzero. */
2899 template_parm_this_level_p (tree t, void* data)
2901 int this_level = *(int *)data;
2904 if (TREE_CODE (t) == TEMPLATE_PARM_INDEX)
2905 level = TEMPLATE_PARM_LEVEL (t);
2907 level = TEMPLATE_TYPE_LEVEL (t);
2908 return level == this_level;
2911 /* Creates a TEMPLATE_DECL for the indicated DECL using the template
2912 parameters given by current_template_args, or reuses a
2913 previously existing one, if appropriate. Returns the DECL, or an
2914 equivalent one, if it is replaced via a call to duplicate_decls.
2916 If IS_FRIEND is true, DECL is a friend declaration. */
2919 push_template_decl_real (tree decl, bool is_friend)
2927 int new_template_p = 0;
2928 /* True if the template is a member template, in the sense of
2930 bool member_template_p = false;
2932 if (decl == error_mark_node)
2935 /* See if this is a partial specialization. */
2936 is_partial = (DECL_IMPLICIT_TYPEDEF_P (decl)
2937 && TREE_CODE (TREE_TYPE (decl)) != ENUMERAL_TYPE
2938 && CLASSTYPE_TEMPLATE_SPECIALIZATION (TREE_TYPE (decl)));
2940 if (TREE_CODE (decl) == FUNCTION_DECL && DECL_FRIEND_P (decl))
2944 /* For a friend, we want the context of the friend function, not
2945 the type of which it is a friend. */
2946 ctx = DECL_CONTEXT (decl);
2947 else if (CP_DECL_CONTEXT (decl)
2948 && TREE_CODE (CP_DECL_CONTEXT (decl)) != NAMESPACE_DECL)
2949 /* In the case of a virtual function, we want the class in which
2951 ctx = CP_DECL_CONTEXT (decl);
2953 /* Otherwise, if we're currently defining some class, the DECL
2954 is assumed to be a member of the class. */
2955 ctx = current_scope ();
2957 if (ctx && TREE_CODE (ctx) == NAMESPACE_DECL)
2960 if (!DECL_CONTEXT (decl))
2961 DECL_CONTEXT (decl) = FROB_CONTEXT (current_namespace);
2963 /* See if this is a primary template. */
2964 primary = template_parm_scope_p ();
2968 if (DECL_CLASS_SCOPE_P (decl))
2969 member_template_p = true;
2970 if (current_lang_name == lang_name_c)
2971 error ("template with C linkage");
2972 else if (TREE_CODE (decl) == TYPE_DECL
2973 && ANON_AGGRNAME_P (DECL_NAME (decl)))
2974 error ("template class without a name");
2975 else if (TREE_CODE (decl) == FUNCTION_DECL)
2977 if (DECL_DESTRUCTOR_P (decl))
2981 A destructor shall not be a member template. */
2982 error ("destructor %qD declared as member template", decl);
2983 return error_mark_node;
2985 if (NEW_DELETE_OPNAME_P (DECL_NAME (decl))
2986 && (!TYPE_ARG_TYPES (TREE_TYPE (decl))
2987 || TYPE_ARG_TYPES (TREE_TYPE (decl)) == void_list_node
2988 || !TREE_CHAIN (TYPE_ARG_TYPES (TREE_TYPE (decl)))
2989 || (TREE_CHAIN (TYPE_ARG_TYPES ((TREE_TYPE (decl))))
2990 == void_list_node)))
2992 /* [basic.stc.dynamic.allocation]
2994 An allocation function can be a function
2995 template. ... Template allocation functions shall
2996 have two or more parameters. */
2997 error ("invalid template declaration of %qD", decl);
3001 else if (DECL_IMPLICIT_TYPEDEF_P (decl)
3002 && CLASS_TYPE_P (TREE_TYPE (decl)))
3006 error ("template declaration of %q#D", decl);
3007 return error_mark_node;
3011 /* Check to see that the rules regarding the use of default
3012 arguments are not being violated. */
3013 check_default_tmpl_args (decl, current_template_parms,
3014 primary, is_partial);
3017 return process_partial_specialization (decl);
3019 args = current_template_args ();
3022 || TREE_CODE (ctx) == FUNCTION_DECL
3023 || (CLASS_TYPE_P (ctx) && TYPE_BEING_DEFINED (ctx))
3024 || (is_friend && !DECL_TEMPLATE_INFO (decl)))
3026 if (DECL_LANG_SPECIFIC (decl)
3027 && DECL_TEMPLATE_INFO (decl)
3028 && DECL_TI_TEMPLATE (decl))
3029 tmpl = DECL_TI_TEMPLATE (decl);
3030 /* If DECL is a TYPE_DECL for a class-template, then there won't
3031 be DECL_LANG_SPECIFIC. The information equivalent to
3032 DECL_TEMPLATE_INFO is found in TYPE_TEMPLATE_INFO instead. */
3033 else if (DECL_IMPLICIT_TYPEDEF_P (decl)
3034 && TYPE_TEMPLATE_INFO (TREE_TYPE (decl))
3035 && TYPE_TI_TEMPLATE (TREE_TYPE (decl)))
3037 /* Since a template declaration already existed for this
3038 class-type, we must be redeclaring it here. Make sure
3039 that the redeclaration is valid. */
3040 redeclare_class_template (TREE_TYPE (decl),
3041 current_template_parms);
3042 /* We don't need to create a new TEMPLATE_DECL; just use the
3043 one we already had. */
3044 tmpl = TYPE_TI_TEMPLATE (TREE_TYPE (decl));
3048 tmpl = build_template_decl (decl, current_template_parms,
3052 if (DECL_LANG_SPECIFIC (decl)
3053 && DECL_TEMPLATE_SPECIALIZATION (decl))
3055 /* A specialization of a member template of a template
3057 SET_DECL_TEMPLATE_SPECIALIZATION (tmpl);
3058 DECL_TEMPLATE_INFO (tmpl) = DECL_TEMPLATE_INFO (decl);
3059 DECL_TEMPLATE_INFO (decl) = NULL_TREE;
3065 tree a, t, current, parms;
3068 if (TREE_CODE (decl) == TYPE_DECL)
3070 if ((IS_AGGR_TYPE_CODE (TREE_CODE (TREE_TYPE (decl)))
3071 || TREE_CODE (TREE_TYPE (decl)) == ENUMERAL_TYPE)
3072 && TYPE_TEMPLATE_INFO (TREE_TYPE (decl))
3073 && TYPE_TI_TEMPLATE (TREE_TYPE (decl)))
3074 tmpl = TYPE_TI_TEMPLATE (TREE_TYPE (decl));
3077 error ("%qD does not declare a template type", decl);
3081 else if (!DECL_LANG_SPECIFIC (decl) || !DECL_TEMPLATE_INFO (decl))
3083 error ("template definition of non-template %q#D", decl);
3087 tmpl = DECL_TI_TEMPLATE (decl);
3089 if (DECL_FUNCTION_TEMPLATE_P (tmpl)
3090 && DECL_TEMPLATE_INFO (decl) && DECL_TI_ARGS (decl)
3091 && DECL_TEMPLATE_SPECIALIZATION (decl)
3092 && DECL_MEMBER_TEMPLATE_P (tmpl))
3096 /* The declaration is a specialization of a member
3097 template, declared outside the class. Therefore, the
3098 innermost template arguments will be NULL, so we
3099 replace them with the arguments determined by the
3100 earlier call to check_explicit_specialization. */
3101 args = DECL_TI_ARGS (decl);
3104 = build_template_decl (decl, current_template_parms,
3106 DECL_TEMPLATE_RESULT (new_tmpl) = decl;
3107 TREE_TYPE (new_tmpl) = TREE_TYPE (decl);
3108 DECL_TI_TEMPLATE (decl) = new_tmpl;
3109 SET_DECL_TEMPLATE_SPECIALIZATION (new_tmpl);
3110 DECL_TEMPLATE_INFO (new_tmpl)
3111 = tree_cons (tmpl, args, NULL_TREE);
3113 register_specialization (new_tmpl,
3114 most_general_template (tmpl),
3120 /* Make sure the template headers we got make sense. */
3122 parms = DECL_TEMPLATE_PARMS (tmpl);
3123 i = TMPL_PARMS_DEPTH (parms);
3124 if (TMPL_ARGS_DEPTH (args) != i)
3126 error ("expected %d levels of template parms for %q#D, got %d",
3127 i, decl, TMPL_ARGS_DEPTH (args));
3130 for (current = decl; i > 0; --i, parms = TREE_CHAIN (parms))
3132 a = TMPL_ARGS_LEVEL (args, i);
3133 t = INNERMOST_TEMPLATE_PARMS (parms);
3135 if (TREE_VEC_LENGTH (t) != TREE_VEC_LENGTH (a))
3137 if (current == decl)
3138 error ("got %d template parameters for %q#D",
3139 TREE_VEC_LENGTH (a), decl);
3141 error ("got %d template parameters for %q#T",
3142 TREE_VEC_LENGTH (a), current);
3143 error (" but %d required", TREE_VEC_LENGTH (t));
3144 return error_mark_node;
3147 /* Perhaps we should also check that the parms are used in the
3148 appropriate qualifying scopes in the declarator? */
3150 if (current == decl)
3153 current = TYPE_CONTEXT (current);
3157 DECL_TEMPLATE_RESULT (tmpl) = decl;
3158 TREE_TYPE (tmpl) = TREE_TYPE (decl);
3160 /* Push template declarations for global functions and types. Note
3161 that we do not try to push a global template friend declared in a
3162 template class; such a thing may well depend on the template
3163 parameters of the class. */
3164 if (new_template_p && !ctx
3165 && !(is_friend && template_class_depth (current_class_type) > 0))
3167 tmpl = pushdecl_namespace_level (tmpl, is_friend);
3168 if (tmpl == error_mark_node)
3169 return error_mark_node;
3171 /* Hide template friend classes that haven't been declared yet. */
3172 if (is_friend && TREE_CODE (decl) == TYPE_DECL)
3174 DECL_ANTICIPATED (tmpl) = 1;
3175 DECL_FRIEND_P (tmpl) = 1;
3181 DECL_PRIMARY_TEMPLATE (tmpl) = tmpl;
3182 if (DECL_CONV_FN_P (tmpl))
3184 int depth = TMPL_PARMS_DEPTH (DECL_TEMPLATE_PARMS (tmpl));
3186 /* It is a conversion operator. See if the type converted to
3187 depends on innermost template operands. */
3189 if (uses_template_parms_level (TREE_TYPE (TREE_TYPE (tmpl)),
3191 DECL_TEMPLATE_CONV_FN_P (tmpl) = 1;
3195 /* The DECL_TI_ARGS of DECL contains full set of arguments referring
3196 back to its most general template. If TMPL is a specialization,
3197 ARGS may only have the innermost set of arguments. Add the missing
3198 argument levels if necessary. */
3199 if (DECL_TEMPLATE_INFO (tmpl))
3200 args = add_outermost_template_args (DECL_TI_ARGS (tmpl), args);
3202 info = tree_cons (tmpl, args, NULL_TREE);
3204 if (DECL_IMPLICIT_TYPEDEF_P (decl))
3206 SET_TYPE_TEMPLATE_INFO (TREE_TYPE (tmpl), info);
3207 if ((!ctx || TREE_CODE (ctx) != FUNCTION_DECL)
3208 && TREE_CODE (TREE_TYPE (decl)) != ENUMERAL_TYPE
3209 /* Don't change the name if we've already set it up. */
3210 && !IDENTIFIER_TEMPLATE (DECL_NAME (decl)))
3211 DECL_NAME (decl) = classtype_mangled_name (TREE_TYPE (decl));
3213 else if (DECL_LANG_SPECIFIC (decl))
3214 DECL_TEMPLATE_INFO (decl) = info;
3216 return DECL_TEMPLATE_RESULT (tmpl);
3220 push_template_decl (tree decl)
3222 return push_template_decl_real (decl, false);
3225 /* Called when a class template TYPE is redeclared with the indicated
3226 template PARMS, e.g.:
3228 template <class T> struct S;
3229 template <class T> struct S {}; */
3232 redeclare_class_template (tree type, tree parms)
3238 if (!TYPE_TEMPLATE_INFO (type))
3240 error ("%qT is not a template type", type);
3244 tmpl = TYPE_TI_TEMPLATE (type);
3245 if (!PRIMARY_TEMPLATE_P (tmpl))
3246 /* The type is nested in some template class. Nothing to worry
3247 about here; there are no new template parameters for the nested
3253 error ("template specifiers not specified in declaration of %qD",
3258 parms = INNERMOST_TEMPLATE_PARMS (parms);
3259 tmpl_parms = DECL_INNERMOST_TEMPLATE_PARMS (tmpl);
3261 if (TREE_VEC_LENGTH (parms) != TREE_VEC_LENGTH (tmpl_parms))
3263 error ("previous declaration %q+D", tmpl);
3264 error ("used %d template parameter(s) instead of %d",
3265 TREE_VEC_LENGTH (tmpl_parms),
3266 TREE_VEC_LENGTH (parms));
3270 for (i = 0; i < TREE_VEC_LENGTH (tmpl_parms); ++i)
3272 tree tmpl_parm = TREE_VALUE (TREE_VEC_ELT (tmpl_parms, i));
3273 tree parm = TREE_VALUE (TREE_VEC_ELT (parms, i));
3274 tree tmpl_default = TREE_PURPOSE (TREE_VEC_ELT (tmpl_parms, i));
3275 tree parm_default = TREE_PURPOSE (TREE_VEC_ELT (parms, i));
3277 /* TMPL_PARM and PARM can be either TYPE_DECL, PARM_DECL, or
3279 if (TREE_CODE (tmpl_parm) != TREE_CODE (parm)
3280 || (TREE_CODE (tmpl_parm) != TYPE_DECL
3281 && !same_type_p (TREE_TYPE (tmpl_parm), TREE_TYPE (parm))))
3283 error ("template parameter %q+#D", tmpl_parm);
3284 error ("redeclared here as %q#D", parm);
3288 if (tmpl_default != NULL_TREE && parm_default != NULL_TREE)
3290 /* We have in [temp.param]:
3292 A template-parameter may not be given default arguments
3293 by two different declarations in the same scope. */
3294 error ("redefinition of default argument for %q#D", parm);
3295 error ("%J original definition appeared here", tmpl_parm);
3299 if (parm_default != NULL_TREE)
3300 /* Update the previous template parameters (which are the ones
3301 that will really count) with the new default value. */
3302 TREE_PURPOSE (TREE_VEC_ELT (tmpl_parms, i)) = parm_default;
3303 else if (tmpl_default != NULL_TREE)
3304 /* Update the new parameters, too; they'll be used as the
3305 parameters for any members. */
3306 TREE_PURPOSE (TREE_VEC_ELT (parms, i)) = tmpl_default;
3310 /* Simplify EXPR if it is a non-dependent expression. Returns the
3311 (possibly simplified) expression. */
3314 fold_non_dependent_expr (tree expr)
3316 /* If we're in a template, but EXPR isn't value dependent, simplify
3317 it. We're supposed to treat:
3319 template <typename T> void f(T[1 + 1]);
3320 template <typename T> void f(T[2]);
3322 as two declarations of the same function, for example. */
3323 if (processing_template_decl
3324 && !type_dependent_expression_p (expr)
3325 && !value_dependent_expression_p (expr))
3327 HOST_WIDE_INT saved_processing_template_decl;
3329 saved_processing_template_decl = processing_template_decl;
3330 processing_template_decl = 0;
3331 expr = tsubst_copy_and_build (expr,
3334 /*in_decl=*/NULL_TREE,
3335 /*function_p=*/false);
3336 processing_template_decl = saved_processing_template_decl;
3341 /* EXPR is an expression which is used in a constant-expression context.
3342 For instance, it could be a VAR_DECL with a constant initializer.
3343 Extract the innest constant expression.
3345 This is basically a more powerful version of
3346 integral_constant_value, which can be used also in templates where
3347 initializers can maintain a syntactic rather than semantic form
3348 (even if they are non-dependent, for access-checking purposes). */
3351 fold_decl_constant_value (tree expr)
3353 tree const_expr = expr;
3356 expr = fold_non_dependent_expr (const_expr);
3357 const_expr = integral_constant_value (expr);
3359 while (expr != const_expr);
3364 /* Subroutine of convert_nontype_argument. Converts EXPR to TYPE, which
3365 must be a function or a pointer-to-function type, as specified
3366 in [temp.arg.nontype]: disambiguate EXPR if it is an overload set,
3367 and check that the resulting function has external linkage. */
3370 convert_nontype_argument_function (tree type, tree expr)
3375 fn = instantiate_type (type, fns, tf_none);
3376 if (fn == error_mark_node)
3377 return error_mark_node;
3380 if (TREE_CODE (fn_no_ptr) == ADDR_EXPR)
3381 fn_no_ptr = TREE_OPERAND (fn_no_ptr, 0);
3383 /* [temp.arg.nontype]/1
3385 A template-argument for a non-type, non-template template-parameter
3388 -- the address of an object or function with external linkage. */
3389 if (!DECL_EXTERNAL_LINKAGE_P (fn_no_ptr))
3391 error ("%qE is not a valid template argument for type %qT "
3392 "because function %qD has not external linkage",
3393 expr, type, fn_no_ptr);
3400 /* Attempt to convert the non-type template parameter EXPR to the
3401 indicated TYPE. If the conversion is successful, return the
3402 converted value. If the conversion is unsuccessful, return
3403 NULL_TREE if we issued an error message, or error_mark_node if we
3404 did not. We issue error messages for out-and-out bad template
3405 parameters, but not simply because the conversion failed, since we
3406 might be just trying to do argument deduction. Both TYPE and EXPR
3407 must be non-dependent.
3409 The conversion follows the special rules described in
3410 [temp.arg.nontype], and it is much more strict than an implicit
3413 This function is called twice for each template argument (see
3414 lookup_template_class for a more accurate description of this
3415 problem). This means that we need to handle expressions which
3416 are not valid in a C++ source, but can be created from the
3417 first call (for instance, casts to perform conversions). These
3418 hacks can go away after we fix the double coercion problem. */
3421 convert_nontype_argument (tree type, tree expr)
3425 /* Detect immediately string literals as invalid non-type argument.
3426 This special-case is not needed for correctness (we would easily
3427 catch this later), but only to provide better diagnostic for this
3428 common user mistake. As suggested by DR 100, we do not mention
3429 linkage issues in the diagnostic as this is not the point. */
3430 if (TREE_CODE (expr) == STRING_CST)
3432 error ("%qE is not a valid template argument for type %qT "
3433 "because string literals can never be used in this context",
3438 /* If we are in a template, EXPR may be non-dependent, but still
3439 have a syntactic, rather than semantic, form. For example, EXPR
3440 might be a SCOPE_REF, rather than the VAR_DECL to which the
3441 SCOPE_REF refers. Preserving the qualifying scope is necessary
3442 so that access checking can be performed when the template is
3443 instantiated -- but here we need the resolved form so that we can
3444 convert the argument. */
3445 expr = fold_non_dependent_expr (expr);
3446 expr_type = TREE_TYPE (expr);
3448 /* HACK: Due to double coercion, we can get a
3449 NOP_EXPR<REFERENCE_TYPE>(ADDR_EXPR<POINTER_TYPE> (arg)) here,
3450 which is the tree that we built on the first call (see
3451 below when coercing to reference to object or to reference to
3452 function). We just strip everything and get to the arg.
3453 See g++.old-deja/g++.oliva/template4.C and g++.dg/template/nontype9.C
3455 if (TREE_CODE (expr) == NOP_EXPR)
3457 if (TYPE_REF_OBJ_P (type) || TYPE_REFFN_P (type))
3459 /* ??? Maybe we could use convert_from_reference here, but we
3460 would need to relax its constraints because the NOP_EXPR
3461 could actually change the type to something more cv-qualified,
3462 and this is not folded by convert_from_reference. */
3463 tree addr = TREE_OPERAND (expr, 0);
3464 gcc_assert (TREE_CODE (expr_type) == REFERENCE_TYPE);
3465 gcc_assert (TREE_CODE (addr) == ADDR_EXPR);
3466 gcc_assert (TREE_CODE (TREE_TYPE (addr)) == POINTER_TYPE);
3467 gcc_assert (same_type_ignoring_top_level_qualifiers_p
3468 (TREE_TYPE (expr_type),
3469 TREE_TYPE (TREE_TYPE (addr))));
3471 expr = TREE_OPERAND (addr, 0);
3472 expr_type = TREE_TYPE (expr);
3475 /* We could also generate a NOP_EXPR(ADDR_EXPR()) when the
3476 parameter is a pointer to object, through decay and
3477 qualification conversion. Let's strip everything. */
3478 else if (TYPE_PTROBV_P (type))
3481 gcc_assert (TREE_CODE (expr) == ADDR_EXPR);
3482 gcc_assert (TREE_CODE (TREE_TYPE (expr)) == POINTER_TYPE);
3483 /* Skip the ADDR_EXPR only if it is part of the decay for
3484 an array. Otherwise, it is part of the original argument
3485 in the source code. */
3486 if (TREE_CODE (TREE_TYPE (TREE_OPERAND (expr, 0))) == ARRAY_TYPE)
3487 expr = TREE_OPERAND (expr, 0);
3488 expr_type = TREE_TYPE (expr);
3492 /* [temp.arg.nontype]/5, bullet 1
3494 For a non-type template-parameter of integral or enumeration type,
3495 integral promotions (_conv.prom_) and integral conversions
3496 (_conv.integral_) are applied. */
3497 if (INTEGRAL_TYPE_P (type))
3499 if (!INTEGRAL_TYPE_P (expr_type))
3500 return error_mark_node;
3502 expr = fold_decl_constant_value (expr);
3503 /* Notice that there are constant expressions like '4 % 0' which
3504 do not fold into integer constants. */
3505 if (TREE_CODE (expr) != INTEGER_CST)
3507 error ("%qE is not a valid template argument for type %qT "
3508 "because it is a non-constant expression", expr, type);
3512 /* At this point, an implicit conversion does what we want,
3513 because we already know that the expression is of integral
3515 expr = ocp_convert (type, expr, CONV_IMPLICIT, LOOKUP_PROTECT);
3516 if (expr == error_mark_node)
3517 return error_mark_node;
3519 /* Conversion was allowed: fold it to a bare integer constant. */
3522 /* [temp.arg.nontype]/5, bullet 2
3524 For a non-type template-parameter of type pointer to object,
3525 qualification conversions (_conv.qual_) and the array-to-pointer
3526 conversion (_conv.array_) are applied. */
3527 else if (TYPE_PTROBV_P (type))
3529 /* [temp.arg.nontype]/1 (TC1 version, DR 49):
3531 A template-argument for a non-type, non-template template-parameter
3532 shall be one of: [...]
3534 -- the name of a non-type template-parameter;
3535 -- the address of an object or function with external linkage, [...]
3536 expressed as "& id-expression" where the & is optional if the name
3537 refers to a function or array, or if the corresponding
3538 template-parameter is a reference.
3540 Here, we do not care about functions, as they are invalid anyway
3541 for a parameter of type pointer-to-object. */
3542 bool constant_address_p =
3543 (TREE_CODE (expr) == ADDR_EXPR
3544 || TREE_CODE (expr_type) == ARRAY_TYPE
3545 || (DECL_P (expr) && DECL_TEMPLATE_PARM_P (expr)));
3547 expr = decay_conversion (expr);
3548 if (expr == error_mark_node)
3549 return error_mark_node;
3551 expr = perform_qualification_conversions (type, expr);
3552 if (expr == error_mark_node)
3553 return error_mark_node;
3555 if (!constant_address_p)
3557 error ("%qE is not a valid template argument for type %qT "
3558 "because it is not a constant pointer", expr, type);
3562 /* [temp.arg.nontype]/5, bullet 3
3564 For a non-type template-parameter of type reference to object, no
3565 conversions apply. The type referred to by the reference may be more
3566 cv-qualified than the (otherwise identical) type of the
3567 template-argument. The template-parameter is bound directly to the
3568 template-argument, which must be an lvalue. */
3569 else if (TYPE_REF_OBJ_P (type))
3571 if (!same_type_ignoring_top_level_qualifiers_p (TREE_TYPE (type),
3573 return error_mark_node;
3575 if (!at_least_as_qualified_p (TREE_TYPE (type), expr_type))
3577 error ("%qE is not a valid template argument for type %qT "
3578 "because of conflicts in cv-qualification", expr, type);
3582 if (!real_lvalue_p (expr))
3584 error ("%qE is not a valid template argument for type %qT "
3585 "because it is not a lvalue", expr, type);
3589 /* [temp.arg.nontype]/1
3591 A template-argument for a non-type, non-template template-parameter
3592 shall be one of: [...]
3594 -- the address of an object or function with external linkage. */
3595 if (!DECL_EXTERNAL_LINKAGE_P (expr))
3597 error ("%qE is not a valid template argument for type %qT "
3598 "because object %qD has not external linkage",
3603 expr = build_nop (type, build_address (expr));
3605 /* [temp.arg.nontype]/5, bullet 4
3607 For a non-type template-parameter of type pointer to function, only
3608 the function-to-pointer conversion (_conv.func_) is applied. If the
3609 template-argument represents a set of overloaded functions (or a
3610 pointer to such), the matching function is selected from the set
3612 else if (TYPE_PTRFN_P (type))
3614 /* If the argument is a template-id, we might not have enough
3615 context information to decay the pointer. */
3616 if (!type_unknown_p (expr_type))
3618 expr = decay_conversion (expr);
3619 if (expr == error_mark_node)
3620 return error_mark_node;
3623 expr = convert_nontype_argument_function (type, expr);
3624 if (!expr || expr == error_mark_node)
3627 /* [temp.arg.nontype]/5, bullet 5
3629 For a non-type template-parameter of type reference to function, no
3630 conversions apply. If the template-argument represents a set of
3631 overloaded functions, the matching function is selected from the set
3633 else if (TYPE_REFFN_P (type))
3635 if (TREE_CODE (expr) == ADDR_EXPR)
3637 error ("%qE is not a valid template argument for type %qT "
3638 "because it is a pointer", expr, type);
3639 inform ("try using %qE instead", TREE_OPERAND (expr, 0));
3643 expr = convert_nontype_argument_function (TREE_TYPE (type), expr);
3644 if (!expr || expr == error_mark_node)
3647 expr = build_nop (type, build_address (expr));
3649 /* [temp.arg.nontype]/5, bullet 6
3651 For a non-type template-parameter of type pointer to member function,
3652 no conversions apply. If the template-argument represents a set of
3653 overloaded member functions, the matching member function is selected
3654 from the set (_over.over_). */
3655 else if (TYPE_PTRMEMFUNC_P (type))
3657 expr = instantiate_type (type, expr, tf_none);
3658 if (expr == error_mark_node)
3659 return error_mark_node;
3661 /* There is no way to disable standard conversions in
3662 resolve_address_of_overloaded_function (called by
3663 instantiate_type). It is possible that the call succeeded by
3664 converting &B::I to &D::I (where B is a base of D), so we need
3665 to reject this conversion here.
3667 Actually, even if there was a way to disable standard conversions,
3668 it would still be better to reject them here so that we can
3669 provide a superior diagnostic. */
3670 if (!same_type_p (TREE_TYPE (expr), type))
3672 /* Make sure we are just one standard conversion off. */
3673 gcc_assert (can_convert (type, TREE_TYPE (expr)));
3674 error ("%qE is not a valid template argument for type %qT "
3675 "because it is of type %qT", expr, type,
3677 inform ("standard conversions are not allowed in this context");
3681 /* [temp.arg.nontype]/5, bullet 7
3683 For a non-type template-parameter of type pointer to data member,
3684 qualification conversions (_conv.qual_) are applied. */
3685 else if (TYPE_PTRMEM_P (type))
3687 expr = perform_qualification_conversions (type, expr);
3688 if (expr == error_mark_node)
3691 /* A template non-type parameter must be one of the above. */
3695 /* Sanity check: did we actually convert the argument to the
3697 gcc_assert (same_type_p (type, TREE_TYPE (expr)));
3702 /* Return 1 if PARM_PARMS and ARG_PARMS matches using rule for
3703 template template parameters. Both PARM_PARMS and ARG_PARMS are
3704 vectors of TREE_LIST nodes containing TYPE_DECL, TEMPLATE_DECL
3707 ARG_PARMS may contain more parameters than PARM_PARMS. If this is
3708 the case, then extra parameters must have default arguments.
3710 Consider the example:
3711 template <class T, class Allocator = allocator> class vector;
3712 template<template <class U> class TT> class C;
3714 C<vector> is a valid instantiation. PARM_PARMS for the above code
3715 contains a TYPE_DECL (for U), ARG_PARMS contains two TYPE_DECLs (for
3716 T and Allocator) and OUTER_ARGS contains the argument that is used to
3717 substitute the TT parameter. */
3720 coerce_template_template_parms (tree parm_parms,
3722 tsubst_flags_t complain,
3726 int nparms, nargs, i;
3729 gcc_assert (TREE_CODE (parm_parms) == TREE_VEC);
3730 gcc_assert (TREE_CODE (arg_parms) == TREE_VEC);
3732 nparms = TREE_VEC_LENGTH (parm_parms);
3733 nargs = TREE_VEC_LENGTH (arg_parms);
3735 /* The rule here is opposite of coerce_template_parms. */
3738 && TREE_PURPOSE (TREE_VEC_ELT (arg_parms, nparms)) == NULL_TREE))
3741 for (i = 0; i < nparms; ++i)
3743 parm = TREE_VALUE (TREE_VEC_ELT (parm_parms, i));
3744 arg = TREE_VALUE (TREE_VEC_ELT (arg_parms, i));
3746 if (arg == NULL_TREE || arg == error_mark_node
3747 || parm == NULL_TREE || parm == error_mark_node)
3750 if (TREE_CODE (arg) != TREE_CODE (parm))
3753 switch (TREE_CODE (parm))
3759 /* We encounter instantiations of templates like
3760 template <template <template <class> class> class TT>
3763 tree parmparm = DECL_INNERMOST_TEMPLATE_PARMS (parm);
3764 tree argparm = DECL_INNERMOST_TEMPLATE_PARMS (arg);
3766 if (!coerce_template_template_parms
3767 (parmparm, argparm, complain, in_decl, outer_args))
3773 /* The tsubst call is used to handle cases such as
3775 template <int> class C {};
3776 template <class T, template <T> class TT> class D {};
3779 i.e. the parameter list of TT depends on earlier parameters. */
3780 if (!dependent_type_p (TREE_TYPE (arg))
3782 (tsubst (TREE_TYPE (parm), outer_args, complain, in_decl),
3794 /* Convert the indicated template ARG as necessary to match the
3795 indicated template PARM. Returns the converted ARG, or
3796 error_mark_node if the conversion was unsuccessful. Error and
3797 warning messages are issued under control of COMPLAIN. This
3798 conversion is for the Ith parameter in the parameter list. ARGS is
3799 the full set of template arguments deduced so far. */
3802 convert_template_argument (tree parm,
3805 tsubst_flags_t complain,
3811 int is_type, requires_type, is_tmpl_type, requires_tmpl_type;
3813 inner_args = INNERMOST_TEMPLATE_ARGS (args);
3815 if (TREE_CODE (arg) == TREE_LIST
3816 && TREE_CODE (TREE_VALUE (arg)) == OFFSET_REF)
3818 /* The template argument was the name of some
3819 member function. That's usually
3820 invalid, but static members are OK. In any
3821 case, grab the underlying fields/functions
3822 and issue an error later if required. */
3823 arg = TREE_VALUE (arg);
3824 TREE_TYPE (arg) = unknown_type_node;
3827 requires_tmpl_type = TREE_CODE (parm) == TEMPLATE_DECL;
3828 requires_type = (TREE_CODE (parm) == TYPE_DECL
3829 || requires_tmpl_type);
3831 is_tmpl_type = ((TREE_CODE (arg) == TEMPLATE_DECL
3832 && TREE_CODE (DECL_TEMPLATE_RESULT (arg)) == TYPE_DECL)
3833 || TREE_CODE (arg) == TEMPLATE_TEMPLATE_PARM
3834 || TREE_CODE (arg) == UNBOUND_CLASS_TEMPLATE);
3837 && (TREE_CODE (arg) == TEMPLATE_TEMPLATE_PARM
3838 || TREE_CODE (arg) == UNBOUND_CLASS_TEMPLATE))
3839 arg = TYPE_STUB_DECL (arg);
3841 is_type = TYPE_P (arg) || is_tmpl_type;
3843 if (requires_type && ! is_type && TREE_CODE (arg) == SCOPE_REF
3844 && TREE_CODE (TREE_OPERAND (arg, 0)) == TEMPLATE_TYPE_PARM)
3846 pedwarn ("to refer to a type member of a template parameter, "
3847 "use %<typename %E%>", arg);
3849 arg = make_typename_type (TREE_OPERAND (arg, 0),
3850 TREE_OPERAND (arg, 1),
3852 complain & tf_error);
3855 if (is_type != requires_type)
3859 if (complain & tf_error)
3861 error ("type/value mismatch at argument %d in template "
3862 "parameter list for %qD",
3865 error (" expected a constant of type %qT, got %qT",
3867 (is_tmpl_type ? DECL_NAME (arg) : arg));
3868 else if (requires_tmpl_type)
3869 error (" expected a class template, got %qE", arg);
3871 error (" expected a type, got %qE", arg);
3874 return error_mark_node;
3876 if (is_tmpl_type ^ requires_tmpl_type)
3878 if (in_decl && (complain & tf_error))
3880 error ("type/value mismatch at argument %d in template "
3881 "parameter list for %qD",
3884 error (" expected a type, got %qT", DECL_NAME (arg));
3886 error (" expected a class template, got %qT", arg);
3888 return error_mark_node;
3893 if (requires_tmpl_type)
3895 if (TREE_CODE (TREE_TYPE (arg)) == UNBOUND_CLASS_TEMPLATE)
3896 /* The number of argument required is not known yet.
3897 Just accept it for now. */
3898 val = TREE_TYPE (arg);
3901 tree parmparm = DECL_INNERMOST_TEMPLATE_PARMS (parm);
3902 tree argparm = DECL_INNERMOST_TEMPLATE_PARMS (arg);
3904 if (coerce_template_template_parms (parmparm, argparm,
3910 /* TEMPLATE_TEMPLATE_PARM node is preferred over
3912 if (val != error_mark_node
3913 && DECL_TEMPLATE_TEMPLATE_PARM_P (val))
3914 val = TREE_TYPE (val);
3918 if (in_decl && (complain & tf_error))
3920 error ("type/value mismatch at argument %d in "
3921 "template parameter list for %qD",
3923 error (" expected a template of type %qD, got %qD",
3927 val = error_mark_node;
3936 tree t = tsubst (TREE_TYPE (parm), args, complain, in_decl);
3938 if (invalid_nontype_parm_type_p (t, complain))
3939 return error_mark_node;
3941 if (!uses_template_parms (arg) && !uses_template_parms (t))
3942 /* We used to call digest_init here. However, digest_init
3943 will report errors, which we don't want when complain
3944 is zero. More importantly, digest_init will try too
3945 hard to convert things: for example, `0' should not be
3946 converted to pointer type at this point according to
3947 the standard. Accepting this is not merely an
3948 extension, since deciding whether or not these
3949 conversions can occur is part of determining which
3950 function template to call, or whether a given explicit
3951 argument specification is valid. */
3952 val = convert_nontype_argument (t, arg);
3956 if (val == NULL_TREE)
3957 val = error_mark_node;
3958 else if (val == error_mark_node && (complain & tf_error))
3959 error ("could not convert template argument %qE to %qT", arg, t);
3965 /* Convert all template arguments to their appropriate types, and
3966 return a vector containing the innermost resulting template
3967 arguments. If any error occurs, return error_mark_node. Error and
3968 warning messages are issued under control of COMPLAIN.
3970 If REQUIRE_ALL_ARGUMENTS is nonzero, all arguments must be
3971 provided in ARGLIST, or else trailing parameters must have default
3972 values. If REQUIRE_ALL_ARGUMENTS is zero, we will attempt argument
3973 deduction for any unspecified trailing arguments. */
3976 coerce_template_parms (tree parms,
3979 tsubst_flags_t complain,
3980 int require_all_arguments)
3982 int nparms, nargs, i, lost = 0;
3985 tree new_inner_args;
3987 inner_args = INNERMOST_TEMPLATE_ARGS (args);
3988 nargs = inner_args ? NUM_TMPL_ARGS (inner_args) : 0;
3989 nparms = TREE_VEC_LENGTH (parms);
3993 && require_all_arguments
3994 && TREE_PURPOSE (TREE_VEC_ELT (parms, nargs)) == NULL_TREE))
3996 if (complain & tf_error)
3998 error ("wrong number of template arguments (%d, should be %d)",
4002 error ("provided for %q+D", in_decl);
4005 return error_mark_node;
4008 new_inner_args = make_tree_vec (nparms);
4009 new_args = add_outermost_template_args (args, new_inner_args);
4010 for (i = 0; i < nparms; i++)
4015 /* Get the Ith template parameter. */
4016 parm = TREE_VEC_ELT (parms, i);
4018 /* Calculate the Ith argument. */
4020 arg = TREE_VEC_ELT (inner_args, i);
4021 else if (require_all_arguments)
4022 /* There must be a default arg in this case. */
4023 arg = tsubst_template_arg (TREE_PURPOSE (parm), new_args,
4029 if (arg == error_mark_node)
4031 if (complain & tf_error)
4032 error ("template argument %d is invalid", i + 1);
4035 arg = convert_template_argument (TREE_VALUE (parm),
4036 arg, new_args, complain, i,
4039 if (arg == error_mark_node)
4041 TREE_VEC_ELT (new_inner_args, i) = arg;
4045 return error_mark_node;
4047 return new_inner_args;
4050 /* Returns 1 if template args OT and NT are equivalent. */
4053 template_args_equal (tree ot, tree nt)
4058 if (TREE_CODE (nt) == TREE_VEC)
4059 /* For member templates */
4060 return TREE_CODE (ot) == TREE_VEC && comp_template_args (ot, nt);
4061 else if (TYPE_P (nt))
4062 return TYPE_P (ot) && same_type_p (ot, nt);
4063 else if (TREE_CODE (ot) == TREE_VEC || TYPE_P (ot))
4066 return cp_tree_equal (ot, nt);
4069 /* Returns 1 iff the OLDARGS and NEWARGS are in fact identical sets
4070 of template arguments. Returns 0 otherwise. */
4073 comp_template_args (tree oldargs, tree newargs)
4077 if (TREE_VEC_LENGTH (oldargs) != TREE_VEC_LENGTH (newargs))
4080 for (i = 0; i < TREE_VEC_LENGTH (oldargs); ++i)
4082 tree nt = TREE_VEC_ELT (newargs, i);
4083 tree ot = TREE_VEC_ELT (oldargs, i);
4085 if (! template_args_equal (ot, nt))
4091 /* Given class template name and parameter list, produce a user-friendly name
4092 for the instantiation. */
4095 mangle_class_name_for_template (const char* name, tree parms, tree arglist)
4097 static struct obstack scratch_obstack;
4098 static char *scratch_firstobj;
4101 if (!scratch_firstobj)
4102 gcc_obstack_init (&scratch_obstack);
4104 obstack_free (&scratch_obstack, scratch_firstobj);
4105 scratch_firstobj = obstack_alloc (&scratch_obstack, 1);
4107 #define ccat(C) obstack_1grow (&scratch_obstack, (C));
4108 #define cat(S) obstack_grow (&scratch_obstack, (S), strlen (S))
4112 nparms = TREE_VEC_LENGTH (parms);
4113 arglist = INNERMOST_TEMPLATE_ARGS (arglist);
4114 gcc_assert (nparms == TREE_VEC_LENGTH (arglist));
4115 for (i = 0; i < nparms; i++)
4117 tree parm = TREE_VALUE (TREE_VEC_ELT (parms, i));
4118 tree arg = TREE_VEC_ELT (arglist, i);
4123 if (TREE_CODE (parm) == TYPE_DECL)
4125 cat (type_as_string (arg, TFF_CHASE_TYPEDEF));
4128 else if (TREE_CODE (parm) == TEMPLATE_DECL)
4130 if (TREE_CODE (arg) == TEMPLATE_DECL)
4132 /* Already substituted with real template. Just output
4133 the template name here */
4134 tree context = DECL_CONTEXT (arg);
4137 /* The template may be defined in a namespace, or
4138 may be a member template. */
4139 gcc_assert (TREE_CODE (context) == NAMESPACE_DECL
4140 || CLASS_TYPE_P (context));
4141 cat (decl_as_string (DECL_CONTEXT (arg),
4142 TFF_PLAIN_IDENTIFIER));
4145 cat (IDENTIFIER_POINTER (DECL_NAME (arg)));
4148 /* Output the parameter declaration. */
4149 cat (type_as_string (arg, TFF_CHASE_TYPEDEF));
4153 gcc_assert (TREE_CODE (parm) == PARM_DECL);
4155 /* No need to check arglist against parmlist here; we did that
4156 in coerce_template_parms, called from lookup_template_class. */
4157 cat (expr_as_string (arg, TFF_PLAIN_IDENTIFIER));
4160 char *bufp = obstack_next_free (&scratch_obstack);
4162 while (bufp[offset - 1] == ' ')
4164 obstack_blank_fast (&scratch_obstack, offset);
4166 /* B<C<char> >, not B<C<char>> */
4167 if (bufp[offset - 1] == '>')
4172 return (char *) obstack_base (&scratch_obstack);
4176 classtype_mangled_name (tree t)
4178 if (CLASSTYPE_TEMPLATE_INFO (t)
4179 /* Specializations have already had their names set up in
4180 lookup_template_class. */
4181 && !CLASSTYPE_TEMPLATE_SPECIALIZATION (t))
4183 tree tmpl = most_general_template (CLASSTYPE_TI_TEMPLATE (t));
4185 /* For non-primary templates, the template parameters are
4186 implicit from their surrounding context. */
4187 if (PRIMARY_TEMPLATE_P (tmpl))
4189 tree name = DECL_NAME (tmpl);
4190 char *mangled_name = mangle_class_name_for_template
4191 (IDENTIFIER_POINTER (name),
4192 DECL_INNERMOST_TEMPLATE_PARMS (tmpl),
4193 CLASSTYPE_TI_ARGS (t));
4194 tree id = get_identifier (mangled_name);
4195 IDENTIFIER_TEMPLATE (id) = name;
4200 return TYPE_IDENTIFIER (t);
4204 add_pending_template (tree d)
4206 tree ti = (TYPE_P (d)
4207 ? CLASSTYPE_TEMPLATE_INFO (d)
4208 : DECL_TEMPLATE_INFO (d));
4212 if (TI_PENDING_TEMPLATE_FLAG (ti))
4215 /* We are called both from instantiate_decl, where we've already had a
4216 tinst_level pushed, and instantiate_template, where we haven't.
4218 level = !(current_tinst_level && TINST_DECL (current_tinst_level) == d);
4221 push_tinst_level (d);
4223 pt = tree_cons (current_tinst_level, d, NULL_TREE);
4224 if (last_pending_template)
4225 TREE_CHAIN (last_pending_template) = pt;
4227 pending_templates = pt;
4229 last_pending_template = pt;
4231 TI_PENDING_TEMPLATE_FLAG (ti) = 1;
4238 /* Return a TEMPLATE_ID_EXPR corresponding to the indicated FNS and
4239 ARGLIST. Valid choices for FNS are given in the cp-tree.def
4240 documentation for TEMPLATE_ID_EXPR. */
4243 lookup_template_function (tree fns, tree arglist)
4247 if (fns == error_mark_node || arglist == error_mark_node)
4248 return error_mark_node;
4250 gcc_assert (!arglist || TREE_CODE (arglist) == TREE_VEC);
4251 gcc_assert (fns && (is_overloaded_fn (fns)
4252 || TREE_CODE (fns) == IDENTIFIER_NODE));
4254 if (BASELINK_P (fns))
4256 BASELINK_FUNCTIONS (fns) = build2 (TEMPLATE_ID_EXPR,
4258 BASELINK_FUNCTIONS (fns),
4263 type = TREE_TYPE (fns);
4264 if (TREE_CODE (fns) == OVERLOAD || !type)
4265 type = unknown_type_node;
4267 return build2 (TEMPLATE_ID_EXPR, type, fns, arglist);
4270 /* Within the scope of a template class S<T>, the name S gets bound
4271 (in build_self_reference) to a TYPE_DECL for the class, not a
4272 TEMPLATE_DECL. If DECL is a TYPE_DECL for current_class_type,
4273 or one of its enclosing classes, and that type is a template,
4274 return the associated TEMPLATE_DECL. Otherwise, the original
4275 DECL is returned. */
4278 maybe_get_template_decl_from_type_decl (tree decl)
4280 return (decl != NULL_TREE
4281 && TREE_CODE (decl) == TYPE_DECL
4282 && DECL_ARTIFICIAL (decl)
4283 && CLASS_TYPE_P (TREE_TYPE (decl))
4284 && CLASSTYPE_TEMPLATE_INFO (TREE_TYPE (decl)))
4285 ? CLASSTYPE_TI_TEMPLATE (TREE_TYPE (decl)) : decl;
4288 /* Given an IDENTIFIER_NODE (type TEMPLATE_DECL) and a chain of
4289 parameters, find the desired type.
4291 D1 is the PTYPENAME terminal, and ARGLIST is the list of arguments.
4293 IN_DECL, if non-NULL, is the template declaration we are trying to
4296 If ENTERING_SCOPE is nonzero, we are about to enter the scope of
4297 the class we are looking up.
4299 Issue error and warning messages under control of COMPLAIN.
4301 If the template class is really a local class in a template
4302 function, then the FUNCTION_CONTEXT is the function in which it is
4305 ??? Note that this function is currently called *twice* for each
4306 template-id: the first time from the parser, while creating the
4307 incomplete type (finish_template_type), and the second type during the
4308 real instantiation (instantiate_template_class). This is surely something
4309 that we want to avoid. It also causes some problems with argument
4310 coercion (see convert_nontype_argument for more information on this). */
4313 lookup_template_class (tree d1,
4318 tsubst_flags_t complain)
4320 tree template = NULL_TREE, parmlist;
4323 timevar_push (TV_NAME_LOOKUP);
4325 if (TREE_CODE (d1) == IDENTIFIER_NODE)
4327 tree value = innermost_non_namespace_value (d1);
4328 if (value && DECL_TEMPLATE_TEMPLATE_PARM_P (value))
4333 push_decl_namespace (context);
4334 template = lookup_name (d1, /*prefer_type=*/0);
4335 template = maybe_get_template_decl_from_type_decl (template);
4337 pop_decl_namespace ();
4340 context = DECL_CONTEXT (template);
4342 else if (TREE_CODE (d1) == TYPE_DECL && IS_AGGR_TYPE (TREE_TYPE (d1)))
4344 tree type = TREE_TYPE (d1);
4346 /* If we are declaring a constructor, say A<T>::A<T>, we will get
4347 an implicit typename for the second A. Deal with it. */
4348 if (TREE_CODE (type) == TYPENAME_TYPE && TREE_TYPE (type))
4349 type = TREE_TYPE (type);
4351 if (CLASSTYPE_TEMPLATE_INFO (type))
4353 template = CLASSTYPE_TI_TEMPLATE (type);
4354 d1 = DECL_NAME (template);
4357 else if (TREE_CODE (d1) == ENUMERAL_TYPE
4358 || (TYPE_P (d1) && IS_AGGR_TYPE (d1)))
4360 template = TYPE_TI_TEMPLATE (d1);
4361 d1 = DECL_NAME (template);
4363 else if (TREE_CODE (d1) == TEMPLATE_DECL
4364 && TREE_CODE (DECL_TEMPLATE_RESULT (d1)) == TYPE_DECL)
4367 d1 = DECL_NAME (template);
4368 context = DECL_CONTEXT (template);
4371 /* Issue an error message if we didn't find a template. */
4374 if (complain & tf_error)
4375 error ("%qT is not a template", d1);
4376 POP_TIMEVAR_AND_RETURN (TV_NAME_LOOKUP, error_mark_node);
4379 if (TREE_CODE (template) != TEMPLATE_DECL
4380 /* Make sure it's a user visible template, if it was named by
4382 || ((complain & tf_user) && !DECL_TEMPLATE_PARM_P (template)
4383 && !PRIMARY_TEMPLATE_P (template)))
4385 if (complain & tf_error)
4387 error ("non-template type %qT used as a template", d1);
4389 error ("for template declaration %q+D", in_decl);
4391 POP_TIMEVAR_AND_RETURN (TV_NAME_LOOKUP, error_mark_node);
4394 complain &= ~tf_user;
4396 if (DECL_TEMPLATE_TEMPLATE_PARM_P (template))
4398 /* Create a new TEMPLATE_DECL and TEMPLATE_TEMPLATE_PARM node to store
4399 template arguments */
4404 parmlist = DECL_INNERMOST_TEMPLATE_PARMS (template);
4406 /* Consider an example where a template template parameter declared as
4408 template <class T, class U = std::allocator<T> > class TT
4410 The template parameter level of T and U are one level larger than
4411 of TT. To proper process the default argument of U, say when an
4412 instantiation `TT<int>' is seen, we need to build the full
4413 arguments containing {int} as the innermost level. Outer levels,
4414 available when not appearing as default template argument, can be
4415 obtained from `current_template_args ()'.
4417 Suppose that TT is later substituted with std::vector. The above
4418 instantiation is `TT<int, std::allocator<T> >' with TT at
4419 level 1, and T at level 2, while the template arguments at level 1
4420 becomes {std::vector} and the inner level 2 is {int}. */
4422 if (current_template_parms)
4423 arglist = add_to_template_args (current_template_args (), arglist);
4425 arglist2 = coerce_template_parms (parmlist, arglist, template,
4426 complain, /*require_all_args=*/1);
4427 if (arglist2 == error_mark_node
4428 || (!uses_template_parms (arglist2)
4429 && check_instantiated_args (template, arglist2, complain)))
4430 POP_TIMEVAR_AND_RETURN (TV_NAME_LOOKUP, error_mark_node);
4432 parm = bind_template_template_parm (TREE_TYPE (template), arglist2);
4433 POP_TIMEVAR_AND_RETURN (TV_NAME_LOOKUP, parm);
4437 tree template_type = TREE_TYPE (template);
4440 tree found = NULL_TREE;
4443 int is_partial_instantiation;
4445 gen_tmpl = most_general_template (template);
4446 parmlist = DECL_TEMPLATE_PARMS (gen_tmpl);
4447 parm_depth = TMPL_PARMS_DEPTH (parmlist);
4448 arg_depth = TMPL_ARGS_DEPTH (arglist);
4450 if (arg_depth == 1 && parm_depth > 1)
4452 /* We've been given an incomplete set of template arguments.
4455 template <class T> struct S1 {
4456 template <class U> struct S2 {};
4457 template <class U> struct S2<U*> {};
4460 we will be called with an ARGLIST of `U*', but the
4461 TEMPLATE will be `template <class T> template
4462 <class U> struct S1<T>::S2'. We must fill in the missing
4465 = add_outermost_template_args (TYPE_TI_ARGS (TREE_TYPE (template)),
4467 arg_depth = TMPL_ARGS_DEPTH (arglist);
4470 /* Now we should have enough arguments. */
4471 gcc_assert (parm_depth == arg_depth);
4473 /* From here on, we're only interested in the most general
4475 template = gen_tmpl;
4477 /* Calculate the BOUND_ARGS. These will be the args that are
4478 actually tsubst'd into the definition to create the
4482 /* We have multiple levels of arguments to coerce, at once. */
4484 int saved_depth = TMPL_ARGS_DEPTH (arglist);
4486 tree bound_args = make_tree_vec (parm_depth);
4488 for (i = saved_depth,
4489 t = DECL_TEMPLATE_PARMS (template);
4490 i > 0 && t != NULL_TREE;
4491 --i, t = TREE_CHAIN (t))
4493 tree a = coerce_template_parms (TREE_VALUE (t),
4495 complain, /*require_all_args=*/1);
4497 /* Don't process further if one of the levels fails. */
4498 if (a == error_mark_node)
4500 /* Restore the ARGLIST to its full size. */
4501 TREE_VEC_LENGTH (arglist) = saved_depth;
4502 POP_TIMEVAR_AND_RETURN (TV_NAME_LOOKUP, error_mark_node);
4505 SET_TMPL_ARGS_LEVEL (bound_args, i, a);
4507 /* We temporarily reduce the length of the ARGLIST so
4508 that coerce_template_parms will see only the arguments
4509 corresponding to the template parameters it is
4511 TREE_VEC_LENGTH (arglist)--;
4514 /* Restore the ARGLIST to its full size. */
4515 TREE_VEC_LENGTH (arglist) = saved_depth;
4517 arglist = bound_args;
4521 = coerce_template_parms (INNERMOST_TEMPLATE_PARMS (parmlist),
4522 INNERMOST_TEMPLATE_ARGS (arglist),
4524 complain, /*require_all_args=*/1);
4526 if (arglist == error_mark_node)
4527 /* We were unable to bind the arguments. */
4528 POP_TIMEVAR_AND_RETURN (TV_NAME_LOOKUP, error_mark_node);
4530 /* In the scope of a template class, explicit references to the
4531 template class refer to the type of the template, not any
4532 instantiation of it. For example, in:
4534 template <class T> class C { void f(C<T>); }
4536 the `C<T>' is just the same as `C'. Outside of the
4537 class, however, such a reference is an instantiation. */
4538 if (comp_template_args (TYPE_TI_ARGS (template_type),
4541 found = template_type;
4543 if (!entering_scope && PRIMARY_TEMPLATE_P (template))
4547 for (ctx = current_class_type;
4548 ctx && TREE_CODE (ctx) != NAMESPACE_DECL;
4550 ? TYPE_CONTEXT (ctx)
4551 : DECL_CONTEXT (ctx)))
4552 if (TYPE_P (ctx) && same_type_p (ctx, template_type))
4555 /* We're not in the scope of the class, so the
4556 TEMPLATE_TYPE is not the type we want after all. */
4562 POP_TIMEVAR_AND_RETURN (TV_NAME_LOOKUP, found);
4564 /* If we already have this specialization, return it. */
4565 found = retrieve_specialization (template, arglist,
4566 /*class_specializations_p=*/false);
4568 POP_TIMEVAR_AND_RETURN (TV_NAME_LOOKUP, found);
4570 /* This type is a "partial instantiation" if any of the template
4571 arguments still involve template parameters. Note that we set
4572 IS_PARTIAL_INSTANTIATION for partial specializations as
4574 is_partial_instantiation = uses_template_parms (arglist);
4576 /* If the deduced arguments are invalid, then the binding
4578 if (!is_partial_instantiation
4579 && check_instantiated_args (template,
4580 INNERMOST_TEMPLATE_ARGS (arglist),
4582 POP_TIMEVAR_AND_RETURN (TV_NAME_LOOKUP, error_mark_node);
4584 if (!is_partial_instantiation
4585 && !PRIMARY_TEMPLATE_P (template)
4586 && TREE_CODE (CP_DECL_CONTEXT (template)) == NAMESPACE_DECL)
4588 found = xref_tag_from_type (TREE_TYPE (template),
4589 DECL_NAME (template),
4590 /*tag_scope=*/ts_global);
4591 POP_TIMEVAR_AND_RETURN (TV_NAME_LOOKUP, found);
4594 context = tsubst (DECL_CONTEXT (template), arglist,
4597 context = global_namespace;
4599 /* Create the type. */
4600 if (TREE_CODE (template_type) == ENUMERAL_TYPE)
4602 if (!is_partial_instantiation)
4604 set_current_access_from_decl (TYPE_NAME (template_type));
4605 t = start_enum (TYPE_IDENTIFIER (template_type));
4608 /* We don't want to call start_enum for this type, since
4609 the values for the enumeration constants may involve
4610 template parameters. And, no one should be interested
4611 in the enumeration constants for such a type. */
4612 t = make_node (ENUMERAL_TYPE);
4616 t = make_aggr_type (TREE_CODE (template_type));
4617 CLASSTYPE_DECLARED_CLASS (t)
4618 = CLASSTYPE_DECLARED_CLASS (template_type);
4619 SET_CLASSTYPE_IMPLICIT_INSTANTIATION (t);
4620 TYPE_FOR_JAVA (t) = TYPE_FOR_JAVA (template_type);
4622 /* A local class. Make sure the decl gets registered properly. */
4623 if (context == current_function_decl)
4624 pushtag (DECL_NAME (template), t, /*tag_scope=*/ts_current);
4627 /* If we called start_enum or pushtag above, this information
4628 will already be set up. */
4631 TYPE_CONTEXT (t) = FROB_CONTEXT (context);
4633 type_decl = create_implicit_typedef (DECL_NAME (template), t);
4634 DECL_CONTEXT (type_decl) = TYPE_CONTEXT (t);
4635 TYPE_STUB_DECL (t) = type_decl;
4636 DECL_SOURCE_LOCATION (type_decl)
4637 = DECL_SOURCE_LOCATION (TYPE_STUB_DECL (template_type));
4640 type_decl = TYPE_NAME (t);
4642 TREE_PRIVATE (type_decl)
4643 = TREE_PRIVATE (TYPE_STUB_DECL (template_type));
4644 TREE_PROTECTED (type_decl)
4645 = TREE_PROTECTED (TYPE_STUB_DECL (template_type));
4646 DECL_IN_SYSTEM_HEADER (type_decl)
4647 = DECL_IN_SYSTEM_HEADER (template);
4648 if (CLASSTYPE_VISIBILITY_SPECIFIED (template_type))
4650 DECL_VISIBILITY_SPECIFIED (type_decl) = 1;
4651 DECL_VISIBILITY (type_decl) = CLASSTYPE_VISIBILITY (template_type);
4654 /* Set up the template information. We have to figure out which
4655 template is the immediate parent if this is a full
4657 if (parm_depth == 1 || is_partial_instantiation
4658 || !PRIMARY_TEMPLATE_P (template))
4659 /* This case is easy; there are no member templates involved. */
4663 /* This is a full instantiation of a member template. Look
4664 for a partial instantiation of which this is an instance. */
4666 for (found = DECL_TEMPLATE_INSTANTIATIONS (template);
4667 found; found = TREE_CHAIN (found))
4670 tree tmpl = CLASSTYPE_TI_TEMPLATE (TREE_VALUE (found));
4672 /* We only want partial instantiations, here, not
4673 specializations or full instantiations. */
4674 if (CLASSTYPE_TEMPLATE_SPECIALIZATION (TREE_VALUE (found))
4675 || !uses_template_parms (TREE_VALUE (found)))
4678 /* Temporarily reduce by one the number of levels in the
4679 ARGLIST and in FOUND so as to avoid comparing the
4680 last set of arguments. */
4681 TREE_VEC_LENGTH (arglist)--;
4682 TREE_VEC_LENGTH (TREE_PURPOSE (found)) --;
4684 /* See if the arguments match. If they do, then TMPL is
4685 the partial instantiation we want. */
4686 success = comp_template_args (TREE_PURPOSE (found), arglist);
4688 /* Restore the argument vectors to their full size. */
4689 TREE_VEC_LENGTH (arglist)++;
4690 TREE_VEC_LENGTH (TREE_PURPOSE (found))++;
4701 /* There was no partial instantiation. This happens
4702 where C<T> is a member template of A<T> and it's used
4705 template <typename T> struct B { A<T>::C<int> m; };
4708 Create the partial instantiation.
4710 TREE_VEC_LENGTH (arglist)--;
4711 found = tsubst (template, arglist, complain, NULL_TREE);
4712 TREE_VEC_LENGTH (arglist)++;
4716 SET_TYPE_TEMPLATE_INFO (t, tree_cons (found, arglist, NULL_TREE));
4717 DECL_TEMPLATE_INSTANTIATIONS (template)
4718 = tree_cons (arglist, t,
4719 DECL_TEMPLATE_INSTANTIATIONS (template));
4721 if (TREE_CODE (t) == ENUMERAL_TYPE
4722 && !is_partial_instantiation)
4723 /* Now that the type has been registered on the instantiations
4724 list, we set up the enumerators. Because the enumeration
4725 constants may involve the enumeration type itself, we make
4726 sure to register the type first, and then create the
4727 constants. That way, doing tsubst_expr for the enumeration
4728 constants won't result in recursive calls here; we'll find
4729 the instantiation and exit above. */
4730 tsubst_enum (template_type, t, arglist);
4732 /* Reset the name of the type, now that CLASSTYPE_TEMPLATE_INFO
4734 if (TREE_CODE (t) != ENUMERAL_TYPE)
4735 DECL_NAME (type_decl) = classtype_mangled_name (t);
4736 if (is_partial_instantiation)
4737 /* If the type makes use of template parameters, the
4738 code that generates debugging information will crash. */
4739 DECL_IGNORED_P (TYPE_STUB_DECL (t)) = 1;
4741 POP_TIMEVAR_AND_RETURN (TV_NAME_LOOKUP, t);
4743 timevar_pop (TV_NAME_LOOKUP);
4750 struct pointer_set_t *visited;
4753 /* Called from for_each_template_parm via walk_tree. */
4756 for_each_template_parm_r (tree *tp, int *walk_subtrees, void *d)
4759 struct pair_fn_data *pfd = (struct pair_fn_data *) d;
4760 tree_fn_t fn = pfd->fn;
4761 void *data = pfd->data;
4764 && for_each_template_parm (TYPE_CONTEXT (t), fn, data, pfd->visited))
4765 return error_mark_node;
4767 switch (TREE_CODE (t))
4770 if (TYPE_PTRMEMFUNC_P (t))
4776 if (!TYPE_TEMPLATE_INFO (t))
4778 else if (for_each_template_parm (TREE_VALUE (TYPE_TEMPLATE_INFO (t)),
4779 fn, data, pfd->visited))
4780 return error_mark_node;
4784 /* Since we're not going to walk subtrees, we have to do this
4786 if (for_each_template_parm (TYPE_METHOD_BASETYPE (t), fn, data,
4788 return error_mark_node;
4792 /* Check the return type. */
4793 if (for_each_template_parm (TREE_TYPE (t), fn, data, pfd->visited))
4794 return error_mark_node;
4796 /* Check the parameter types. Since default arguments are not
4797 instantiated until they are needed, the TYPE_ARG_TYPES may
4798 contain expressions that involve template parameters. But,
4799 no-one should be looking at them yet. And, once they're
4800 instantiated, they don't contain template parameters, so
4801 there's no point in looking at them then, either. */
4805 for (parm = TYPE_ARG_TYPES (t); parm; parm = TREE_CHAIN (parm))
4806 if (for_each_template_parm (TREE_VALUE (parm), fn, data,
4808 return error_mark_node;
4810 /* Since we've already handled the TYPE_ARG_TYPES, we don't
4811 want walk_tree walking into them itself. */
4817 if (for_each_template_parm (TYPE_FIELDS (t), fn, data,
4819 return error_mark_node;
4824 if (DECL_LANG_SPECIFIC (t) && DECL_TEMPLATE_INFO (t)
4825 && for_each_template_parm (DECL_TI_ARGS (t), fn, data,
4827 return error_mark_node;
4832 if (TREE_CODE (t) == CONST_DECL && DECL_TEMPLATE_PARM_P (t)
4833 && for_each_template_parm (DECL_INITIAL (t), fn, data,
4835 return error_mark_node;
4836 if (DECL_CONTEXT (t)
4837 && for_each_template_parm (DECL_CONTEXT (t), fn, data,
4839 return error_mark_node;
4842 case BOUND_TEMPLATE_TEMPLATE_PARM:
4843 /* Record template parameters such as `T' inside `TT<T>'. */
4844 if (for_each_template_parm (TYPE_TI_ARGS (t), fn, data, pfd->visited))
4845 return error_mark_node;
4848 case TEMPLATE_TEMPLATE_PARM:
4849 case TEMPLATE_TYPE_PARM:
4850 case TEMPLATE_PARM_INDEX:
4851 if (fn && (*fn)(t, data))
4852 return error_mark_node;
4854 return error_mark_node;
4858 /* A template template parameter is encountered. */
4859 if (DECL_TEMPLATE_TEMPLATE_PARM_P (t)
4860 && for_each_template_parm (TREE_TYPE (t), fn, data, pfd->visited))
4861 return error_mark_node;
4863 /* Already substituted template template parameter */
4869 || for_each_template_parm (TYPENAME_TYPE_FULLNAME (t), fn,
4870 data, pfd->visited))
4871 return error_mark_node;
4875 if (TREE_TYPE (t) && TYPE_PTRMEMFUNC_P (TREE_TYPE (t))
4876 && for_each_template_parm (TYPE_PTRMEMFUNC_FN_TYPE
4877 (TREE_TYPE (t)), fn, data,
4879 return error_mark_node;
4884 /* If there's no type, then this thing must be some expression
4885 involving template parameters. */
4886 if (!fn && !TREE_TYPE (t))
4887 return error_mark_node;
4892 case REINTERPRET_CAST_EXPR:
4893 case CONST_CAST_EXPR:
4894 case STATIC_CAST_EXPR:
4895 case DYNAMIC_CAST_EXPR:
4899 case PSEUDO_DTOR_EXPR:
4901 return error_mark_node;
4905 /* If we do not handle this case specially, we end up walking
4906 the BINFO hierarchy, which is circular, and therefore
4907 confuses walk_tree. */
4909 if (for_each_template_parm (BASELINK_FUNCTIONS (*tp), fn, data,
4911 return error_mark_node;
4918 /* We didn't find any template parameters we liked. */
4922 /* For each TEMPLATE_TYPE_PARM, TEMPLATE_TEMPLATE_PARM,
4923 BOUND_TEMPLATE_TEMPLATE_PARM or TEMPLATE_PARM_INDEX in T,
4924 call FN with the parameter and the DATA.
4925 If FN returns nonzero, the iteration is terminated, and
4926 for_each_template_parm returns 1. Otherwise, the iteration
4927 continues. If FN never returns a nonzero value, the value
4928 returned by for_each_template_parm is 0. If FN is NULL, it is
4929 considered to be the function which always returns 1. */
4932 for_each_template_parm (tree t, tree_fn_t fn, void* data,
4933 struct pointer_set_t *visited)
4935 struct pair_fn_data pfd;
4942 /* Walk the tree. (Conceptually, we would like to walk without
4943 duplicates, but for_each_template_parm_r recursively calls
4944 for_each_template_parm, so we would need to reorganize a fair
4945 bit to use walk_tree_without_duplicates, so we keep our own
4948 pfd.visited = visited;
4950 pfd.visited = pointer_set_create ();
4951 result = walk_tree (&t,
4952 for_each_template_parm_r,
4954 pfd.visited) != NULL_TREE;
4959 pointer_set_destroy (pfd.visited);
4966 /* Returns true if T depends on any template parameter. */
4969 uses_template_parms (tree t)
4972 int saved_processing_template_decl;
4974 saved_processing_template_decl = processing_template_decl;
4975 if (!saved_processing_template_decl)
4976 processing_template_decl = 1;
4978 dependent_p = dependent_type_p (t);
4979 else if (TREE_CODE (t) == TREE_VEC)
4980 dependent_p = any_dependent_template_arguments_p (t);
4981 else if (TREE_CODE (t) == TREE_LIST)
4982 dependent_p = (uses_template_parms (TREE_VALUE (t))
4983 || uses_template_parms (TREE_CHAIN (t)));
4984 else if (TREE_CODE (t) == TYPE_DECL)
4985 dependent_p = dependent_type_p (TREE_TYPE (t));
4988 || TREE_CODE (t) == TEMPLATE_PARM_INDEX
4989 || TREE_CODE (t) == OVERLOAD
4990 || TREE_CODE (t) == BASELINK
4991 || TREE_CODE (t) == IDENTIFIER_NODE
4992 || CONSTANT_CLASS_P (t))
4993 dependent_p = (type_dependent_expression_p (t)
4994 || value_dependent_expression_p (t));
4997 gcc_assert (t == error_mark_node);
4998 dependent_p = false;
5001 processing_template_decl = saved_processing_template_decl;
5006 /* Returns true if T depends on any template parameter with level LEVEL. */
5009 uses_template_parms_level (tree t, int level)
5011 return for_each_template_parm (t, template_parm_this_level_p, &level, NULL);
5014 static int tinst_depth;
5015 extern int max_tinst_depth;
5016 #ifdef GATHER_STATISTICS
5019 static int tinst_level_tick;
5020 static int last_template_error_tick;
5022 /* We're starting to instantiate D; record the template instantiation context
5023 for diagnostics and to restore it later. */
5026 push_tinst_level (tree d)
5030 if (tinst_depth >= max_tinst_depth)
5032 /* If the instantiation in question still has unbound template parms,
5033 we don't really care if we can't instantiate it, so just return.
5034 This happens with base instantiation for implicit `typename'. */
5035 if (uses_template_parms (d))
5038 last_template_error_tick = tinst_level_tick;
5039 error ("template instantiation depth exceeds maximum of %d (use "
5040 "-ftemplate-depth-NN to increase the maximum) instantiating %qD",
5041 max_tinst_depth, d);
5043 print_instantiation_context ();
5048 new = make_node (TINST_LEVEL);
5049 TINST_DECL (new) = d;
5050 TINST_LOCATION (new) = input_location;
5051 TINST_IN_SYSTEM_HEADER_P (new) = in_system_header;
5052 TREE_CHAIN (new) = current_tinst_level;
5053 current_tinst_level = new;
5056 #ifdef GATHER_STATISTICS
5057 if (tinst_depth > depth_reached)
5058 depth_reached = tinst_depth;
5065 /* We're done instantiating this template; return to the instantiation
5069 pop_tinst_level (void)
5071 tree old = current_tinst_level;
5073 /* Restore the filename and line number stashed away when we started
5074 this instantiation. */
5075 input_location = TINST_LOCATION (old);
5076 in_system_header = TINST_IN_SYSTEM_HEADER_P (old);
5077 current_tinst_level = TREE_CHAIN (old);
5082 /* We're instantiating a deferred template; restore the template
5083 instantiation context in which the instantiation was requested, which
5084 is one step out from LEVEL. */
5087 reopen_tinst_level (tree level)
5092 for (t = level; t; t = TREE_CHAIN (t))
5095 current_tinst_level = level;
5099 /* DECL is a friend FUNCTION_DECL or TEMPLATE_DECL. ARGS is the
5100 vector of template arguments, as for tsubst.
5102 Returns an appropriate tsubst'd friend declaration. */
5105 tsubst_friend_function (tree decl, tree args)
5109 if (TREE_CODE (decl) == FUNCTION_DECL
5110 && DECL_TEMPLATE_INSTANTIATION (decl)
5111 && TREE_CODE (DECL_TI_TEMPLATE (decl)) != TEMPLATE_DECL)
5112 /* This was a friend declared with an explicit template
5113 argument list, e.g.:
5117 to indicate that f was a template instantiation, not a new
5118 function declaration. Now, we have to figure out what
5119 instantiation of what template. */
5121 tree template_id, arglist, fns;
5124 tree ns = decl_namespace_context (TYPE_MAIN_DECL (current_class_type));
5126 /* Friend functions are looked up in the containing namespace scope.
5127 We must enter that scope, to avoid finding member functions of the
5128 current cless with same name. */
5129 push_nested_namespace (ns);
5130 fns = tsubst_expr (DECL_TI_TEMPLATE (decl), args,
5131 tf_error | tf_warning, NULL_TREE);
5132 pop_nested_namespace (ns);
5133 arglist = tsubst (DECL_TI_ARGS (decl), args,
5134 tf_error | tf_warning, NULL_TREE);
5135 template_id = lookup_template_function (fns, arglist);
5137 new_friend = tsubst (decl, args, tf_error | tf_warning, NULL_TREE);
5138 tmpl = determine_specialization (template_id, new_friend,
5140 /*need_member_template=*/0,
5141 TREE_VEC_LENGTH (args));
5142 return instantiate_template (tmpl, new_args, tf_error);
5145 new_friend = tsubst (decl, args, tf_error | tf_warning, NULL_TREE);
5147 /* The NEW_FRIEND will look like an instantiation, to the
5148 compiler, but is not an instantiation from the point of view of
5149 the language. For example, we might have had:
5151 template <class T> struct S {
5152 template <class U> friend void f(T, U);
5155 Then, in S<int>, template <class U> void f(int, U) is not an
5156 instantiation of anything. */
5157 if (new_friend == error_mark_node)
5158 return error_mark_node;
5160 DECL_USE_TEMPLATE (new_friend) = 0;
5161 if (TREE_CODE (decl) == TEMPLATE_DECL)
5163 DECL_USE_TEMPLATE (DECL_TEMPLATE_RESULT (new_friend)) = 0;
5164 DECL_SAVED_TREE (DECL_TEMPLATE_RESULT (new_friend))
5165 = DECL_SAVED_TREE (DECL_TEMPLATE_RESULT (decl));
5168 /* The mangled name for the NEW_FRIEND is incorrect. The function
5169 is not a template instantiation and should not be mangled like
5170 one. Therefore, we forget the mangling here; we'll recompute it
5171 later if we need it. */
5172 if (TREE_CODE (new_friend) != TEMPLATE_DECL)
5174 SET_DECL_RTL (new_friend, NULL_RTX);
5175 SET_DECL_ASSEMBLER_NAME (new_friend, NULL_TREE);
5178 if (DECL_NAMESPACE_SCOPE_P (new_friend))
5181 tree new_friend_template_info;
5182 tree new_friend_result_template_info;
5184 int new_friend_is_defn;
5186 /* We must save some information from NEW_FRIEND before calling
5187 duplicate decls since that function will free NEW_FRIEND if
5189 new_friend_template_info = DECL_TEMPLATE_INFO (new_friend);
5190 new_friend_is_defn =
5191 (DECL_INITIAL (DECL_TEMPLATE_RESULT
5192 (template_for_substitution (new_friend)))
5194 if (TREE_CODE (new_friend) == TEMPLATE_DECL)
5196 /* This declaration is a `primary' template. */
5197 DECL_PRIMARY_TEMPLATE (new_friend) = new_friend;
5199 new_friend_result_template_info
5200 = DECL_TEMPLATE_INFO (DECL_TEMPLATE_RESULT (new_friend));
5203 new_friend_result_template_info = NULL_TREE;
5205 /* Inside pushdecl_namespace_level, we will push into the
5206 current namespace. However, the friend function should go
5207 into the namespace of the template. */
5208 ns = decl_namespace_context (new_friend);
5209 push_nested_namespace (ns);
5210 old_decl = pushdecl_namespace_level (new_friend, /*is_friend=*/true);
5211 pop_nested_namespace (ns);
5213 if (old_decl != new_friend)
5215 /* This new friend declaration matched an existing
5216 declaration. For example, given:
5218 template <class T> void f(T);
5219 template <class U> class C {
5220 template <class T> friend void f(T) {}
5223 the friend declaration actually provides the definition
5224 of `f', once C has been instantiated for some type. So,
5225 old_decl will be the out-of-class template declaration,
5226 while new_friend is the in-class definition.
5228 But, if `f' was called before this point, the
5229 instantiation of `f' will have DECL_TI_ARGS corresponding
5230 to `T' but not to `U', references to which might appear
5231 in the definition of `f'. Previously, the most general
5232 template for an instantiation of `f' was the out-of-class
5233 version; now it is the in-class version. Therefore, we
5234 run through all specialization of `f', adding to their
5235 DECL_TI_ARGS appropriately. In particular, they need a
5236 new set of outer arguments, corresponding to the
5237 arguments for this class instantiation.
5239 The same situation can arise with something like this:
5242 template <class T> class C {
5246 when `C<int>' is instantiated. Now, `f(int)' is defined
5249 if (!new_friend_is_defn)
5250 /* On the other hand, if the in-class declaration does
5251 *not* provide a definition, then we don't want to alter
5252 existing definitions. We can just leave everything
5257 /* Overwrite whatever template info was there before, if
5258 any, with the new template information pertaining to
5260 DECL_TEMPLATE_INFO (old_decl) = new_friend_template_info;
5262 if (TREE_CODE (old_decl) != TEMPLATE_DECL)
5263 reregister_specialization (new_friend,
5264 most_general_template (old_decl),
5269 tree new_friend_args;
5271 DECL_TEMPLATE_INFO (DECL_TEMPLATE_RESULT (old_decl))
5272 = new_friend_result_template_info;
5274 new_friend_args = TI_ARGS (new_friend_template_info);
5275 for (t = DECL_TEMPLATE_SPECIALIZATIONS (old_decl);
5279 tree spec = TREE_VALUE (t);
5282 = add_outermost_template_args (new_friend_args,
5283 DECL_TI_ARGS (spec));
5286 /* Now, since specializations are always supposed to
5287 hang off of the most general template, we must move
5289 t = most_general_template (old_decl);
5292 DECL_TEMPLATE_SPECIALIZATIONS (t)
5293 = chainon (DECL_TEMPLATE_SPECIALIZATIONS (t),
5294 DECL_TEMPLATE_SPECIALIZATIONS (old_decl));
5295 DECL_TEMPLATE_SPECIALIZATIONS (old_decl) = NULL_TREE;
5300 /* The information from NEW_FRIEND has been merged into OLD_DECL
5301 by duplicate_decls. */
5302 new_friend = old_decl;
5307 tree context = DECL_CONTEXT (new_friend);
5311 template <class T> class C {
5312 template <class U> friend void C1<U>::f (); // case 1
5313 friend void C2<T>::f (); // case 2
5315 we only need to make sure CONTEXT is a complete type for
5316 case 2. To distinguish between the two cases, we note that
5317 CONTEXT of case 1 remains dependent type after tsubst while
5318 this isn't true for case 2. */
5319 ++processing_template_decl;
5320 dependent_p = dependent_type_p (context);
5321 --processing_template_decl;
5324 && !complete_type_or_else (context, NULL_TREE))
5325 return error_mark_node;
5327 if (COMPLETE_TYPE_P (context))
5329 /* Check to see that the declaration is really present, and,
5330 possibly obtain an improved declaration. */
5331 tree fn = check_classfn (context,
5332 new_friend, NULL_TREE);
5342 /* FRIEND_TMPL is a friend TEMPLATE_DECL. ARGS is the vector of
5343 template arguments, as for tsubst.
5345 Returns an appropriate tsubst'd friend type or error_mark_node on
5349 tsubst_friend_class (tree friend_tmpl, tree args)
5355 context = DECL_CONTEXT (friend_tmpl);
5359 if (TREE_CODE (context) == NAMESPACE_DECL)
5360 push_nested_namespace (context);
5362 push_nested_class (tsubst (context, args, tf_none, NULL_TREE));
5365 /* First, we look for a class template. */
5366 tmpl = lookup_name (DECL_NAME (friend_tmpl), /*prefer_type=*/0);
5368 /* But, if we don't find one, it might be because we're in a
5369 situation like this:
5377 Here, in the scope of (say) S<int>, `S' is bound to a TYPE_DECL
5378 for `S<int>', not the TEMPLATE_DECL. */
5379 if (!tmpl || !DECL_CLASS_TEMPLATE_P (tmpl))
5381 tmpl = lookup_name (DECL_NAME (friend_tmpl), /*prefer_type=*/1);
5382 tmpl = maybe_get_template_decl_from_type_decl (tmpl);
5385 if (tmpl && DECL_CLASS_TEMPLATE_P (tmpl))
5387 /* The friend template has already been declared. Just
5388 check to see that the declarations match, and install any new
5389 default parameters. We must tsubst the default parameters,
5390 of course. We only need the innermost template parameters
5391 because that is all that redeclare_class_template will look
5393 if (TMPL_PARMS_DEPTH (DECL_TEMPLATE_PARMS (friend_tmpl))
5394 > TMPL_ARGS_DEPTH (args))
5397 parms = tsubst_template_parms (DECL_TEMPLATE_PARMS (friend_tmpl),
5398 args, tf_error | tf_warning);
5399 redeclare_class_template (TREE_TYPE (tmpl), parms);
5402 friend_type = TREE_TYPE (tmpl);
5406 /* The friend template has not already been declared. In this
5407 case, the instantiation of the template class will cause the
5408 injection of this template into the global scope. */
5409 tmpl = tsubst (friend_tmpl, args, tf_error | tf_warning, NULL_TREE);
5411 /* The new TMPL is not an instantiation of anything, so we
5412 forget its origins. We don't reset CLASSTYPE_TI_TEMPLATE for
5413 the new type because that is supposed to be the corresponding
5414 template decl, i.e., TMPL. */
5415 DECL_USE_TEMPLATE (tmpl) = 0;
5416 DECL_TEMPLATE_INFO (tmpl) = NULL_TREE;
5417 CLASSTYPE_USE_TEMPLATE (TREE_TYPE (tmpl)) = 0;
5418 CLASSTYPE_TI_ARGS (TREE_TYPE (tmpl))
5419 = INNERMOST_TEMPLATE_ARGS (CLASSTYPE_TI_ARGS (TREE_TYPE (tmpl)));
5421 /* Inject this template into the global scope. */
5422 friend_type = TREE_TYPE (pushdecl_top_level_maybe_friend (tmpl, true));
5427 if (TREE_CODE (context) == NAMESPACE_DECL)
5428 pop_nested_namespace (context);
5430 pop_nested_class ();
5436 /* Returns zero if TYPE cannot be completed later due to circularity.
5437 Otherwise returns one. */
5440 can_complete_type_without_circularity (tree type)
5442 if (type == NULL_TREE || type == error_mark_node)
5444 else if (COMPLETE_TYPE_P (type))
5446 else if (TREE_CODE (type) == ARRAY_TYPE && TYPE_DOMAIN (type))
5447 return can_complete_type_without_circularity (TREE_TYPE (type));
5448 else if (CLASS_TYPE_P (type)
5449 && TYPE_BEING_DEFINED (TYPE_MAIN_VARIANT (type)))
5456 instantiate_class_template (tree type)
5458 tree template, args, pattern, t, member;
5463 if (type == error_mark_node)
5464 return error_mark_node;
5466 if (TYPE_BEING_DEFINED (type)
5467 || COMPLETE_TYPE_P (type)
5468 || dependent_type_p (type))
5471 /* Figure out which template is being instantiated. */
5472 template = most_general_template (CLASSTYPE_TI_TEMPLATE (type));
5473 gcc_assert (TREE_CODE (template) == TEMPLATE_DECL);
5475 /* Figure out which arguments are being used to do the
5477 args = CLASSTYPE_TI_ARGS (type);
5479 /* Determine what specialization of the original template to
5481 t = most_specialized_class (template, args);
5482 if (t == error_mark_node)
5484 const char *str = "candidates are:";
5485 error ("ambiguous class template instantiation for %q#T", type);
5486 for (t = DECL_TEMPLATE_SPECIALIZATIONS (template); t;
5489 if (get_class_bindings (TREE_VALUE (t), TREE_PURPOSE (t), args))
5491 error ("%s %+#T", str, TREE_TYPE (t));
5495 TYPE_BEING_DEFINED (type) = 1;
5496 return error_mark_node;
5500 pattern = TREE_TYPE (t);
5502 pattern = TREE_TYPE (template);
5504 /* If the template we're instantiating is incomplete, then clearly
5505 there's nothing we can do. */
5506 if (!COMPLETE_TYPE_P (pattern))
5509 /* If we've recursively instantiated too many templates, stop. */
5510 if (! push_tinst_level (type))
5513 /* Now we're really doing the instantiation. Mark the type as in
5514 the process of being defined. */
5515 TYPE_BEING_DEFINED (type) = 1;
5517 /* We may be in the middle of deferred access check. Disable
5519 push_deferring_access_checks (dk_no_deferred);
5521 push_to_top_level ();
5525 /* This TYPE is actually an instantiation of a partial
5526 specialization. We replace the innermost set of ARGS with
5527 the arguments appropriate for substitution. For example,
5530 template <class T> struct S {};
5531 template <class T> struct S<T*> {};
5533 and supposing that we are instantiating S<int*>, ARGS will
5534 present be {int*} but we need {int}. */
5536 = get_class_bindings (TREE_VALUE (t), TREE_PURPOSE (t),
5539 /* If there were multiple levels in ARGS, replacing the
5540 innermost level would alter CLASSTYPE_TI_ARGS, which we don't
5541 want, so we make a copy first. */
5542 if (TMPL_ARGS_HAVE_MULTIPLE_LEVELS (args))
5544 args = copy_node (args);
5545 SET_TMPL_ARGS_LEVEL (args, TMPL_ARGS_DEPTH (args), inner_args);
5551 SET_CLASSTYPE_INTERFACE_UNKNOWN (type);
5553 /* Set the input location to the template definition. This is needed
5554 if tsubsting causes an error. */
5555 typedecl = TYPE_MAIN_DECL (type);
5556 input_location = DECL_SOURCE_LOCATION (typedecl);
5557 in_system_header = DECL_IN_SYSTEM_HEADER (typedecl);
5559 TYPE_HAS_CONSTRUCTOR (type) = TYPE_HAS_CONSTRUCTOR (pattern);
5560 TYPE_HAS_NEW_OPERATOR (type) = TYPE_HAS_NEW_OPERATOR (pattern);
5561 TYPE_HAS_ARRAY_NEW_OPERATOR (type) = TYPE_HAS_ARRAY_NEW_OPERATOR (pattern);
5562 TYPE_GETS_DELETE (type) = TYPE_GETS_DELETE (pattern);
5563 TYPE_HAS_ASSIGN_REF (type) = TYPE_HAS_ASSIGN_REF (pattern);
5564 TYPE_HAS_CONST_ASSIGN_REF (type) = TYPE_HAS_CONST_ASSIGN_REF (pattern);
5565 TYPE_HAS_INIT_REF (type) = TYPE_HAS_INIT_REF (pattern);
5566 TYPE_HAS_CONST_INIT_REF (type) = TYPE_HAS_CONST_INIT_REF (pattern);
5567 TYPE_HAS_DEFAULT_CONSTRUCTOR (type) = TYPE_HAS_DEFAULT_CONSTRUCTOR (pattern);
5568 TYPE_HAS_CONVERSION (type) = TYPE_HAS_CONVERSION (pattern);
5569 TYPE_PACKED (type) = TYPE_PACKED (pattern);
5570 TYPE_ALIGN (type) = TYPE_ALIGN (pattern);
5571 TYPE_USER_ALIGN (type) = TYPE_USER_ALIGN (pattern);
5572 TYPE_FOR_JAVA (type) = TYPE_FOR_JAVA (pattern); /* For libjava's JArray<T> */
5573 if (ANON_AGGR_TYPE_P (pattern))
5574 SET_ANON_AGGR_TYPE_P (type);
5575 if (CLASSTYPE_VISIBILITY_SPECIFIED (pattern))
5577 CLASSTYPE_VISIBILITY_SPECIFIED (type) = 1;
5578 CLASSTYPE_VISIBILITY (type) = CLASSTYPE_VISIBILITY (pattern);
5581 pbinfo = TYPE_BINFO (pattern);
5583 /* We should never instantiate a nested class before its enclosing
5584 class; we need to look up the nested class by name before we can
5585 instantiate it, and that lookup should instantiate the enclosing
5587 gcc_assert (!DECL_CLASS_SCOPE_P (TYPE_MAIN_DECL (pattern))
5588 || COMPLETE_TYPE_P (TYPE_CONTEXT (type))
5589 || TYPE_BEING_DEFINED (TYPE_CONTEXT (type)));
5591 base_list = NULL_TREE;
5592 if (BINFO_N_BASE_BINFOS (pbinfo))
5595 tree context = TYPE_CONTEXT (type);
5599 /* We must enter the scope containing the type, as that is where
5600 the accessibility of types named in dependent bases are
5602 pushed_scope = push_scope (context ? context : global_namespace);
5604 /* Substitute into each of the bases to determine the actual
5606 for (i = 0; BINFO_BASE_ITERATE (pbinfo, i, pbase_binfo); i++)
5609 tree access = BINFO_BASE_ACCESS (pbinfo, i);
5611 /* Substitute to figure out the base class. */
5612 base = tsubst (BINFO_TYPE (pbase_binfo), args, tf_error, NULL_TREE);
5613 if (base == error_mark_node)
5616 base_list = tree_cons (access, base, base_list);
5617 if (BINFO_VIRTUAL_P (pbase_binfo))
5618 TREE_TYPE (base_list) = integer_type_node;
5621 /* The list is now in reverse order; correct that. */
5622 base_list = nreverse (base_list);
5625 pop_scope (pushed_scope);
5627 /* Now call xref_basetypes to set up all the base-class
5629 xref_basetypes (type, base_list);
5632 /* Now that our base classes are set up, enter the scope of the
5633 class, so that name lookups into base classes, etc. will work
5634 correctly. This is precisely analogous to what we do in
5635 begin_class_definition when defining an ordinary non-template
5639 /* Now members are processed in the order of declaration. */
5640 for (member = CLASSTYPE_DECL_LIST (pattern);
5641 member; member = TREE_CHAIN (member))
5643 tree t = TREE_VALUE (member);
5645 if (TREE_PURPOSE (member))
5649 /* Build new CLASSTYPE_NESTED_UTDS. */
5652 tree name = TYPE_IDENTIFIER (tag);
5654 bool class_template_p;
5656 class_template_p = (TREE_CODE (tag) != ENUMERAL_TYPE
5657 && TYPE_LANG_SPECIFIC (tag)
5658 && CLASSTYPE_IS_TEMPLATE (tag));
5659 /* If the member is a class template, then -- even after
5660 substitution -- there may be dependent types in the
5661 template argument list for the class. We increment
5662 PROCESSING_TEMPLATE_DECL so that dependent_type_p, as
5663 that function will assume that no types are dependent
5664 when outside of a template. */
5665 if (class_template_p)
5666 ++processing_template_decl;
5667 newtag = tsubst (tag, args, tf_error, NULL_TREE);
5668 if (class_template_p)
5669 --processing_template_decl;
5670 if (newtag == error_mark_node)
5673 if (TREE_CODE (newtag) != ENUMERAL_TYPE)
5675 if (class_template_p)
5676 /* Unfortunately, lookup_template_class sets
5677 CLASSTYPE_IMPLICIT_INSTANTIATION for a partial
5678 instantiation (i.e., for the type of a member
5679 template class nested within a template class.)
5680 This behavior is required for
5681 maybe_process_partial_specialization to work
5682 correctly, but is not accurate in this case;
5683 the TAG is not an instantiation of anything.
5684 (The corresponding TEMPLATE_DECL is an
5685 instantiation, but the TYPE is not.) */
5686 CLASSTYPE_USE_TEMPLATE (newtag) = 0;
5688 /* Now, we call pushtag to put this NEWTAG into the scope of
5689 TYPE. We first set up the IDENTIFIER_TYPE_VALUE to avoid
5690 pushtag calling push_template_decl. We don't have to do
5691 this for enums because it will already have been done in
5694 SET_IDENTIFIER_TYPE_VALUE (name, newtag);
5695 pushtag (name, newtag, /*tag_scope=*/ts_current);
5698 else if (TREE_CODE (t) == FUNCTION_DECL
5699 || DECL_FUNCTION_TEMPLATE_P (t))
5701 /* Build new TYPE_METHODS. */
5704 if (TREE_CODE (t) == TEMPLATE_DECL)
5705 ++processing_template_decl;
5706 r = tsubst (t, args, tf_error, NULL_TREE);
5707 if (TREE_CODE (t) == TEMPLATE_DECL)
5708 --processing_template_decl;
5709 set_current_access_from_decl (r);
5710 grok_special_member_properties (r);
5711 finish_member_declaration (r);
5715 /* Build new TYPE_FIELDS. */
5717 if (TREE_CODE (t) != CONST_DECL)
5721 /* The the file and line for this declaration, to
5722 assist in error message reporting. Since we
5723 called push_tinst_level above, we don't need to
5725 input_location = DECL_SOURCE_LOCATION (t);
5727 if (TREE_CODE (t) == TEMPLATE_DECL)
5728 ++processing_template_decl;
5729 r = tsubst (t, args, tf_error | tf_warning, NULL_TREE);
5730 if (TREE_CODE (t) == TEMPLATE_DECL)
5731 --processing_template_decl;
5732 if (TREE_CODE (r) == VAR_DECL)
5736 [t]he initialization (and any associated
5737 side-effects) of a static data member does
5738 not occur unless the static data member is
5739 itself used in a way that requires the
5740 definition of the static data member to
5743 Therefore, we do not substitute into the
5744 initialized for the static data member here. */
5745 finish_static_data_member_decl
5748 /*asmspec_tree=*/NULL_TREE,
5750 if (DECL_INITIALIZED_IN_CLASS_P (r))
5751 check_static_variable_definition (r, TREE_TYPE (r));
5753 else if (TREE_CODE (r) == FIELD_DECL)
5755 /* Determine whether R has a valid type and can be
5756 completed later. If R is invalid, then it is
5757 replaced by error_mark_node so that it will not be
5758 added to TYPE_FIELDS. */
5759 tree rtype = TREE_TYPE (r);
5760 if (can_complete_type_without_circularity (rtype))
5761 complete_type (rtype);
5763 if (!COMPLETE_TYPE_P (rtype))
5765 cxx_incomplete_type_error (r, rtype);
5766 r = error_mark_node;
5770 /* If it is a TYPE_DECL for a class-scoped ENUMERAL_TYPE,
5771 such a thing will already have been added to the field
5772 list by tsubst_enum in finish_member_declaration in the
5773 CLASSTYPE_NESTED_UTDS case above. */
5774 if (!(TREE_CODE (r) == TYPE_DECL
5775 && TREE_CODE (TREE_TYPE (r)) == ENUMERAL_TYPE
5776 && DECL_ARTIFICIAL (r)))
5778 set_current_access_from_decl (r);
5779 finish_member_declaration (r);
5786 if (TYPE_P (t) || DECL_CLASS_TEMPLATE_P (t))
5788 /* Build new CLASSTYPE_FRIEND_CLASSES. */
5790 tree friend_type = t;
5791 bool adjust_processing_template_decl = false;
5793 if (TREE_CODE (friend_type) == TEMPLATE_DECL)
5795 /* template <class T> friend class C; */
5796 friend_type = tsubst_friend_class (friend_type, args);
5797 adjust_processing_template_decl = true;
5799 else if (TREE_CODE (friend_type) == UNBOUND_CLASS_TEMPLATE)
5801 /* template <class T> friend class C::D; */
5802 friend_type = tsubst (friend_type, args,
5803 tf_error | tf_warning, NULL_TREE);
5804 if (TREE_CODE (friend_type) == TEMPLATE_DECL)
5805 friend_type = TREE_TYPE (friend_type);
5806 adjust_processing_template_decl = true;
5808 else if (TREE_CODE (friend_type) == TYPENAME_TYPE)
5810 /* This could be either
5814 when dependent_type_p is false or
5816 template <class U> friend class T::C;
5819 friend_type = tsubst (friend_type, args,
5820 tf_error | tf_warning, NULL_TREE);
5821 /* Bump processing_template_decl for correct
5822 dependent_type_p calculation. */
5823 ++processing_template_decl;
5824 if (dependent_type_p (friend_type))
5825 adjust_processing_template_decl = true;
5826 --processing_template_decl;
5828 else if (!CLASSTYPE_USE_TEMPLATE (friend_type)
5829 && hidden_name_p (TYPE_NAME (friend_type)))
5833 where C hasn't been declared yet. Let's lookup name
5834 from namespace scope directly, bypassing any name that
5835 come from dependent base class. */
5836 tree ns = decl_namespace_context (TYPE_MAIN_DECL (friend_type));
5838 /* The call to xref_tag_from_type does injection for friend
5840 push_nested_namespace (ns);
5842 xref_tag_from_type (friend_type, NULL_TREE,
5843 /*tag_scope=*/ts_current);
5844 pop_nested_namespace (ns);
5846 else if (uses_template_parms (friend_type))
5847 /* friend class C<T>; */
5848 friend_type = tsubst (friend_type, args,
5849 tf_error | tf_warning, NULL_TREE);
5854 where C is already declared or
5856 friend class C<int>;
5858 We don't have to do anything in these cases. */
5860 if (adjust_processing_template_decl)
5861 /* Trick make_friend_class into realizing that the friend
5862 we're adding is a template, not an ordinary class. It's
5863 important that we use make_friend_class since it will
5864 perform some error-checking and output cross-reference
5866 ++processing_template_decl;
5868 if (friend_type != error_mark_node)
5869 make_friend_class (type, friend_type, /*complain=*/false);
5871 if (adjust_processing_template_decl)
5872 --processing_template_decl;
5876 /* Build new DECL_FRIENDLIST. */
5879 /* The the file and line for this declaration, to
5880 assist in error message reporting. Since we
5881 called push_tinst_level above, we don't need to
5883 input_location = DECL_SOURCE_LOCATION (t);
5885 if (TREE_CODE (t) == TEMPLATE_DECL)
5887 ++processing_template_decl;
5888 push_deferring_access_checks (dk_no_check);
5891 r = tsubst_friend_function (t, args);
5892 add_friend (type, r, /*complain=*/false);
5893 if (TREE_CODE (t) == TEMPLATE_DECL)
5895 pop_deferring_access_checks ();
5896 --processing_template_decl;
5902 /* Set the file and line number information to whatever is given for
5903 the class itself. This puts error messages involving generated
5904 implicit functions at a predictable point, and the same point
5905 that would be used for non-template classes. */
5906 input_location = DECL_SOURCE_LOCATION (typedecl);
5908 unreverse_member_declarations (type);
5909 finish_struct_1 (type);
5910 TYPE_BEING_DEFINED (type) = 0;
5912 /* Now that the class is complete, instantiate default arguments for
5913 any member functions. We don't do this earlier because the
5914 default arguments may reference members of the class. */
5915 if (!PRIMARY_TEMPLATE_P (template))
5916 for (t = TYPE_METHODS (type); t; t = TREE_CHAIN (t))
5917 if (TREE_CODE (t) == FUNCTION_DECL
5918 /* Implicitly generated member functions will not have template
5919 information; they are not instantiations, but instead are
5920 created "fresh" for each instantiation. */
5921 && DECL_TEMPLATE_INFO (t))
5922 tsubst_default_arguments (t);
5925 pop_from_top_level ();
5926 pop_deferring_access_checks ();
5929 /* The vtable for a template class can be emitted in any translation
5930 unit in which the class is instantiated. When there is no key
5931 method, however, finish_struct_1 will already have added TYPE to
5932 the keyed_classes list. */
5933 if (TYPE_CONTAINS_VPTR_P (type) && CLASSTYPE_KEY_METHOD (type))
5934 keyed_classes = tree_cons (NULL_TREE, type, keyed_classes);
5940 tsubst_template_arg (tree t, tree args, tsubst_flags_t complain, tree in_decl)
5946 else if (TYPE_P (t))
5947 r = tsubst (t, args, complain, in_decl);
5950 r = tsubst_expr (t, args, complain, in_decl);
5951 r = fold_non_dependent_expr (r);
5956 /* Substitute ARGS into the vector or list of template arguments T. */
5959 tsubst_template_args (tree t, tree args, tsubst_flags_t complain, tree in_decl)
5961 int len = TREE_VEC_LENGTH (t);
5962 int need_new = 0, i;
5963 tree *elts = alloca (len * sizeof (tree));
5965 for (i = 0; i < len; i++)
5967 tree orig_arg = TREE_VEC_ELT (t, i);
5970 if (TREE_CODE (orig_arg) == TREE_VEC)
5971 new_arg = tsubst_template_args (orig_arg, args, complain, in_decl);
5973 new_arg = tsubst_template_arg (orig_arg, args, complain, in_decl);
5975 if (new_arg == error_mark_node)
5976 return error_mark_node;
5979 if (new_arg != orig_arg)
5986 t = make_tree_vec (len);
5987 for (i = 0; i < len; i++)
5988 TREE_VEC_ELT (t, i) = elts[i];
5993 /* Return the result of substituting ARGS into the template parameters
5994 given by PARMS. If there are m levels of ARGS and m + n levels of
5995 PARMS, then the result will contain n levels of PARMS. For
5996 example, if PARMS is `template <class T> template <class U>
5997 template <T*, U, class V>' and ARGS is {{int}, {double}} then the
5998 result will be `template <int*, double, class V>'. */
6001 tsubst_template_parms (tree parms, tree args, tsubst_flags_t complain)
6006 /* When substituting into a template, we must set
6007 PROCESSING_TEMPLATE_DECL as the template parameters may be
6008 dependent if they are based on one-another, and the dependency
6009 predicates are short-circuit outside of templates. */
6010 ++processing_template_decl;
6012 for (new_parms = &r;
6013 TMPL_PARMS_DEPTH (parms) > TMPL_ARGS_DEPTH (args);
6014 new_parms = &(TREE_CHAIN (*new_parms)),
6015 parms = TREE_CHAIN (parms))
6018 make_tree_vec (TREE_VEC_LENGTH (TREE_VALUE (parms)));
6021 for (i = 0; i < TREE_VEC_LENGTH (new_vec); ++i)
6023 tree tuple = TREE_VEC_ELT (TREE_VALUE (parms), i);
6024 tree default_value = TREE_PURPOSE (tuple);
6025 tree parm_decl = TREE_VALUE (tuple);
6027 parm_decl = tsubst (parm_decl, args, complain, NULL_TREE);
6028 if (TREE_CODE (parm_decl) == PARM_DECL
6029 && invalid_nontype_parm_type_p (TREE_TYPE (parm_decl), complain))
6030 parm_decl = error_mark_node;
6031 default_value = tsubst_template_arg (default_value, args,
6032 complain, NULL_TREE);
6034 tuple = build_tree_list (default_value, parm_decl);
6035 TREE_VEC_ELT (new_vec, i) = tuple;
6039 tree_cons (size_int (TMPL_PARMS_DEPTH (parms)
6040 - TMPL_ARGS_DEPTH (args)),
6041 new_vec, NULL_TREE);
6044 --processing_template_decl;
6049 /* Substitute the ARGS into the indicated aggregate (or enumeration)
6050 type T. If T is not an aggregate or enumeration type, it is
6051 handled as if by tsubst. IN_DECL is as for tsubst. If
6052 ENTERING_SCOPE is nonzero, T is the context for a template which
6053 we are presently tsubst'ing. Return the substituted value. */
6056 tsubst_aggr_type (tree t,
6058 tsubst_flags_t complain,
6065 switch (TREE_CODE (t))
6068 if (TYPE_PTRMEMFUNC_P (t))
6069 return tsubst (TYPE_PTRMEMFUNC_FN_TYPE (t), args, complain, in_decl);
6071 /* Else fall through. */
6074 if (TYPE_TEMPLATE_INFO (t))
6079 bool saved_skip_evaluation;
6081 /* In "sizeof(X<I>)" we need to evaluate "I". */
6082 saved_skip_evaluation = skip_evaluation;
6083 skip_evaluation = false;
6085 /* First, determine the context for the type we are looking
6087 context = TYPE_CONTEXT (t);
6089 context = tsubst_aggr_type (context, args, complain,
6090 in_decl, /*entering_scope=*/1);
6092 /* Then, figure out what arguments are appropriate for the
6093 type we are trying to find. For example, given:
6095 template <class T> struct S;
6096 template <class T, class U> void f(T, U) { S<U> su; }
6098 and supposing that we are instantiating f<int, double>,
6099 then our ARGS will be {int, double}, but, when looking up
6100 S we only want {double}. */
6101 argvec = tsubst_template_args (TYPE_TI_ARGS (t), args,
6103 if (argvec == error_mark_node)
6104 r = error_mark_node;
6107 r = lookup_template_class (t, argvec, in_decl, context,
6108 entering_scope, complain);
6109 r = cp_build_qualified_type_real (r, TYPE_QUALS (t), complain);
6112 skip_evaluation = saved_skip_evaluation;
6117 /* This is not a template type, so there's nothing to do. */
6121 return tsubst (t, args, complain, in_decl);
6125 /* Substitute into the default argument ARG (a default argument for
6126 FN), which has the indicated TYPE. */
6129 tsubst_default_argument (tree fn, tree type, tree arg)
6131 tree saved_class_ptr = NULL_TREE;
6132 tree saved_class_ref = NULL_TREE;
6134 /* This default argument came from a template. Instantiate the
6135 default argument here, not in tsubst. In the case of
6144 we must be careful to do name lookup in the scope of S<T>,
6145 rather than in the current class. */
6146 push_access_scope (fn);
6147 /* The "this" pointer is not valid in a default argument. */
6150 saved_class_ptr = current_class_ptr;
6151 cp_function_chain->x_current_class_ptr = NULL_TREE;
6152 saved_class_ref = current_class_ref;
6153 cp_function_chain->x_current_class_ref = NULL_TREE;
6156 push_deferring_access_checks(dk_no_deferred);
6157 arg = tsubst_expr (arg, DECL_TI_ARGS (fn),
6158 tf_error | tf_warning, NULL_TREE);
6159 pop_deferring_access_checks();
6161 /* Restore the "this" pointer. */
6164 cp_function_chain->x_current_class_ptr = saved_class_ptr;
6165 cp_function_chain->x_current_class_ref = saved_class_ref;
6168 pop_access_scope (fn);
6170 /* Make sure the default argument is reasonable. */
6171 arg = check_default_argument (type, arg);
6176 /* Substitute into all the default arguments for FN. */
6179 tsubst_default_arguments (tree fn)
6184 tmpl_args = DECL_TI_ARGS (fn);
6186 /* If this function is not yet instantiated, we certainly don't need
6187 its default arguments. */
6188 if (uses_template_parms (tmpl_args))
6191 for (arg = TYPE_ARG_TYPES (TREE_TYPE (fn));
6193 arg = TREE_CHAIN (arg))
6194 if (TREE_PURPOSE (arg))
6195 TREE_PURPOSE (arg) = tsubst_default_argument (fn,
6197 TREE_PURPOSE (arg));
6200 /* Substitute the ARGS into the T, which is a _DECL. Return the
6201 result of the substitution. Issue error and warning messages under
6202 control of COMPLAIN. */
6205 tsubst_decl (tree t, tree args, tsubst_flags_t complain)
6207 location_t saved_loc;
6211 /* Set the filename and linenumber to improve error-reporting. */
6212 saved_loc = input_location;
6213 input_location = DECL_SOURCE_LOCATION (t);
6215 switch (TREE_CODE (t))
6219 /* We can get here when processing a member function template,
6220 member class template, and template template parameter of
6221 a template class. */
6222 tree decl = DECL_TEMPLATE_RESULT (t);
6227 if (DECL_TEMPLATE_TEMPLATE_PARM_P (t))
6229 /* Template template parameter is treated here. */
6230 tree new_type = tsubst (TREE_TYPE (t), args, complain, in_decl);
6231 if (new_type == error_mark_node)
6232 return error_mark_node;
6235 TREE_CHAIN (r) = NULL_TREE;
6236 TREE_TYPE (r) = new_type;
6237 DECL_TEMPLATE_RESULT (r)
6238 = build_decl (TYPE_DECL, DECL_NAME (decl), new_type);
6239 DECL_TEMPLATE_PARMS (r)
6240 = tsubst_template_parms (DECL_TEMPLATE_PARMS (t), args,
6242 TYPE_NAME (new_type) = r;
6246 /* We might already have an instance of this template.
6247 The ARGS are for the surrounding class type, so the
6248 full args contain the tsubst'd args for the context,
6249 plus the innermost args from the template decl. */
6250 tmpl_args = DECL_CLASS_TEMPLATE_P (t)
6251 ? CLASSTYPE_TI_ARGS (TREE_TYPE (t))
6252 : DECL_TI_ARGS (DECL_TEMPLATE_RESULT (t));
6253 /* Because this is a template, the arguments will still be
6254 dependent, even after substitution. If
6255 PROCESSING_TEMPLATE_DECL is not set, the dependency
6256 predicates will short-circuit. */
6257 ++processing_template_decl;
6258 full_args = tsubst_template_args (tmpl_args, args,
6260 --processing_template_decl;
6261 if (full_args == error_mark_node)
6262 return error_mark_node;
6264 /* tsubst_template_args doesn't copy the vector if
6265 nothing changed. But, *something* should have
6267 gcc_assert (full_args != tmpl_args);
6269 spec = retrieve_specialization (t, full_args,
6270 /*class_specializations_p=*/true);
6271 if (spec != NULL_TREE)
6277 /* Make a new template decl. It will be similar to the
6278 original, but will record the current template arguments.
6279 We also create a new function declaration, which is just
6280 like the old one, but points to this new template, rather
6281 than the old one. */
6283 gcc_assert (DECL_LANG_SPECIFIC (r) != 0);
6284 TREE_CHAIN (r) = NULL_TREE;
6286 DECL_TEMPLATE_INFO (r) = build_tree_list (t, args);
6288 if (TREE_CODE (decl) == TYPE_DECL)
6291 ++processing_template_decl;
6292 new_type = tsubst (TREE_TYPE (t), args, complain, in_decl);
6293 --processing_template_decl;
6294 if (new_type == error_mark_node)
6295 return error_mark_node;
6297 TREE_TYPE (r) = new_type;
6298 CLASSTYPE_TI_TEMPLATE (new_type) = r;
6299 DECL_TEMPLATE_RESULT (r) = TYPE_MAIN_DECL (new_type);
6300 DECL_TI_ARGS (r) = CLASSTYPE_TI_ARGS (new_type);
6301 DECL_CONTEXT (r) = TYPE_CONTEXT (new_type);
6306 ++processing_template_decl;
6307 new_decl = tsubst (decl, args, complain, in_decl);
6308 --processing_template_decl;
6309 if (new_decl == error_mark_node)
6310 return error_mark_node;
6312 DECL_TEMPLATE_RESULT (r) = new_decl;
6313 DECL_TI_TEMPLATE (new_decl) = r;
6314 TREE_TYPE (r) = TREE_TYPE (new_decl);
6315 DECL_TI_ARGS (r) = DECL_TI_ARGS (new_decl);
6316 DECL_CONTEXT (r) = DECL_CONTEXT (new_decl);
6319 SET_DECL_IMPLICIT_INSTANTIATION (r);
6320 DECL_TEMPLATE_INSTANTIATIONS (r) = NULL_TREE;
6321 DECL_TEMPLATE_SPECIALIZATIONS (r) = NULL_TREE;
6323 /* The template parameters for this new template are all the
6324 template parameters for the old template, except the
6325 outermost level of parameters. */
6326 DECL_TEMPLATE_PARMS (r)
6327 = tsubst_template_parms (DECL_TEMPLATE_PARMS (t), args,
6330 if (PRIMARY_TEMPLATE_P (t))
6331 DECL_PRIMARY_TEMPLATE (r) = r;
6333 if (TREE_CODE (decl) != TYPE_DECL)
6334 /* Record this non-type partial instantiation. */
6335 register_specialization (r, t,
6336 DECL_TI_ARGS (DECL_TEMPLATE_RESULT (r)),
6344 tree argvec = NULL_TREE;
6352 /* Nobody should be tsubst'ing into non-template functions. */
6353 gcc_assert (DECL_TEMPLATE_INFO (t) != NULL_TREE);
6355 if (TREE_CODE (DECL_TI_TEMPLATE (t)) == TEMPLATE_DECL)
6360 /* If T is not dependent, just return it. We have to
6361 increment PROCESSING_TEMPLATE_DECL because
6362 value_dependent_expression_p assumes that nothing is
6363 dependent when PROCESSING_TEMPLATE_DECL is zero. */
6364 ++processing_template_decl;
6365 dependent_p = value_dependent_expression_p (t);
6366 --processing_template_decl;
6370 /* Calculate the most general template of which R is a
6371 specialization, and the complete set of arguments used to
6373 gen_tmpl = most_general_template (DECL_TI_TEMPLATE (t));
6374 argvec = tsubst_template_args (DECL_TI_ARGS
6375 (DECL_TEMPLATE_RESULT (gen_tmpl)),
6376 args, complain, in_decl);
6378 /* Check to see if we already have this specialization. */
6379 spec = retrieve_specialization (gen_tmpl, argvec,
6380 /*class_specializations_p=*/false);
6388 /* We can see more levels of arguments than parameters if
6389 there was a specialization of a member template, like
6392 template <class T> struct S { template <class U> void f(); }
6393 template <> template <class U> void S<int>::f(U);
6395 Here, we'll be substituting into the specialization,
6396 because that's where we can find the code we actually
6397 want to generate, but we'll have enough arguments for
6398 the most general template.
6400 We also deal with the peculiar case:
6402 template <class T> struct S {
6403 template <class U> friend void f();
6405 template <class U> void f() {}
6407 template void f<double>();
6409 Here, the ARGS for the instantiation of will be {int,
6410 double}. But, we only need as many ARGS as there are
6411 levels of template parameters in CODE_PATTERN. We are
6412 careful not to get fooled into reducing the ARGS in
6415 template <class T> struct S { template <class U> void f(U); }
6416 template <class T> template <> void S<T>::f(int) {}
6418 which we can spot because the pattern will be a
6419 specialization in this case. */
6420 args_depth = TMPL_ARGS_DEPTH (args);
6422 TMPL_PARMS_DEPTH (DECL_TEMPLATE_PARMS (DECL_TI_TEMPLATE (t)));
6423 if (args_depth > parms_depth
6424 && !DECL_TEMPLATE_SPECIALIZATION (t))
6425 args = get_innermost_template_args (args, parms_depth);
6429 /* This special case arises when we have something like this:
6431 template <class T> struct S {
6432 friend void f<int>(int, double);
6435 Here, the DECL_TI_TEMPLATE for the friend declaration
6436 will be an IDENTIFIER_NODE. We are being called from
6437 tsubst_friend_function, and we want only to create a
6438 new decl (R) with appropriate types so that we can call
6439 determine_specialization. */
6440 gen_tmpl = NULL_TREE;
6443 if (DECL_CLASS_SCOPE_P (t))
6445 if (DECL_NAME (t) == constructor_name (DECL_CONTEXT (t)))
6449 ctx = tsubst_aggr_type (DECL_CONTEXT (t), args,
6450 complain, t, /*entering_scope=*/1);
6455 ctx = DECL_CONTEXT (t);
6457 type = tsubst (TREE_TYPE (t), args, complain, in_decl);
6458 if (type == error_mark_node)
6459 return error_mark_node;
6461 /* We do NOT check for matching decls pushed separately at this
6462 point, as they may not represent instantiations of this
6463 template, and in any case are considered separate under the
6466 DECL_USE_TEMPLATE (r) = 0;
6467 TREE_TYPE (r) = type;
6468 /* Clear out the mangled name and RTL for the instantiation. */
6469 SET_DECL_ASSEMBLER_NAME (r, NULL_TREE);
6470 SET_DECL_RTL (r, NULL_RTX);
6471 DECL_INITIAL (r) = NULL_TREE;
6472 DECL_CONTEXT (r) = ctx;
6474 if (member && DECL_CONV_FN_P (r))
6475 /* Type-conversion operator. Reconstruct the name, in
6476 case it's the name of one of the template's parameters. */
6477 DECL_NAME (r) = mangle_conv_op_name_for_type (TREE_TYPE (type));
6479 DECL_ARGUMENTS (r) = tsubst (DECL_ARGUMENTS (t), args,
6481 DECL_RESULT (r) = NULL_TREE;
6483 TREE_STATIC (r) = 0;
6484 TREE_PUBLIC (r) = TREE_PUBLIC (t);
6485 DECL_EXTERNAL (r) = 1;
6486 /* If this is an instantiation of a function with internal
6487 linkage, we already know what object file linkage will be
6488 assigned to the instantiation. */
6489 DECL_INTERFACE_KNOWN (r) = !TREE_PUBLIC (r);
6490 DECL_DEFER_OUTPUT (r) = 0;
6491 TREE_CHAIN (r) = NULL_TREE;
6492 DECL_PENDING_INLINE_INFO (r) = 0;
6493 DECL_PENDING_INLINE_P (r) = 0;
6494 DECL_SAVED_TREE (r) = NULL_TREE;
6496 if (DECL_CLONED_FUNCTION (r))
6498 DECL_CLONED_FUNCTION (r) = tsubst (DECL_CLONED_FUNCTION (t),
6500 TREE_CHAIN (r) = TREE_CHAIN (DECL_CLONED_FUNCTION (r));
6501 TREE_CHAIN (DECL_CLONED_FUNCTION (r)) = r;
6504 /* Set up the DECL_TEMPLATE_INFO for R. There's no need to do
6505 this in the special friend case mentioned above where
6506 GEN_TMPL is NULL. */
6509 DECL_TEMPLATE_INFO (r)
6510 = tree_cons (gen_tmpl, argvec, NULL_TREE);
6511 SET_DECL_IMPLICIT_INSTANTIATION (r);
6512 register_specialization (r, gen_tmpl, argvec, false);
6514 /* We're not supposed to instantiate default arguments
6515 until they are called, for a template. But, for a
6518 template <class T> void f ()
6519 { extern void g(int i = T()); }
6521 we should do the substitution when the template is
6522 instantiated. We handle the member function case in
6523 instantiate_class_template since the default arguments
6524 might refer to other members of the class. */
6526 && !PRIMARY_TEMPLATE_P (gen_tmpl)
6527 && !uses_template_parms (argvec))
6528 tsubst_default_arguments (r);
6531 DECL_TEMPLATE_INFO (r) = NULL_TREE;
6533 /* Copy the list of befriending classes. */
6534 for (friends = &DECL_BEFRIENDING_CLASSES (r);
6536 friends = &TREE_CHAIN (*friends))
6538 *friends = copy_node (*friends);
6539 TREE_VALUE (*friends) = tsubst (TREE_VALUE (*friends),
6544 if (DECL_CONSTRUCTOR_P (r) || DECL_DESTRUCTOR_P (r))
6546 maybe_retrofit_in_chrg (r);
6547 if (DECL_CONSTRUCTOR_P (r))
6548 grok_ctor_properties (ctx, r);
6549 /* If this is an instantiation of a member template, clone it.
6550 If it isn't, that'll be handled by
6551 clone_constructors_and_destructors. */
6552 if (PRIMARY_TEMPLATE_P (gen_tmpl))
6553 clone_function_decl (r, /*update_method_vec_p=*/0);
6555 else if (IDENTIFIER_OPNAME_P (DECL_NAME (r)))
6556 grok_op_properties (r, (complain & tf_error) != 0);
6558 if (DECL_FRIEND_P (t) && DECL_FRIEND_CONTEXT (t))
6559 SET_DECL_FRIEND_CONTEXT (r,
6560 tsubst (DECL_FRIEND_CONTEXT (t),
6561 args, complain, in_decl));
6570 if (DECL_TEMPLATE_PARM_P (t))
6571 SET_DECL_TEMPLATE_PARM_P (r);
6573 type = tsubst (TREE_TYPE (t), args, complain, in_decl);
6574 type = type_decays_to (type);
6575 TREE_TYPE (r) = type;
6576 cp_apply_type_quals_to_decl (cp_type_quals (type), r);
6578 if (DECL_INITIAL (r))
6580 if (TREE_CODE (DECL_INITIAL (r)) != TEMPLATE_PARM_INDEX)
6581 DECL_INITIAL (r) = TREE_TYPE (r);
6583 DECL_INITIAL (r) = tsubst (DECL_INITIAL (r), args,
6587 DECL_CONTEXT (r) = NULL_TREE;
6589 if (!DECL_TEMPLATE_PARM_P (r))
6590 DECL_ARG_TYPE (r) = type_passed_as (type);
6592 TREE_CHAIN (r) = tsubst (TREE_CHAIN (t), args,
6593 complain, TREE_CHAIN (t));
6602 type = tsubst (TREE_TYPE (t), args, complain, in_decl);
6603 if (type == error_mark_node)
6604 return error_mark_node;
6605 TREE_TYPE (r) = type;
6606 cp_apply_type_quals_to_decl (cp_type_quals (type), r);
6608 /* We don't have to set DECL_CONTEXT here; it is set by
6609 finish_member_declaration. */
6610 DECL_INITIAL (r) = tsubst_expr (DECL_INITIAL (t), args,
6612 TREE_CHAIN (r) = NULL_TREE;
6613 if (VOID_TYPE_P (type))
6614 error ("instantiation of %q+D as type %qT", r, type);
6619 /* We reach here only for member using decls. */
6620 if (DECL_DEPENDENT_P (t))
6622 r = do_class_using_decl
6623 (tsubst_copy (USING_DECL_SCOPE (t), args, complain, in_decl),
6624 tsubst_copy (DECL_NAME (t), args, complain, in_decl));
6626 r = error_mark_node;
6631 TREE_CHAIN (r) = NULL_TREE;
6638 tree argvec = NULL_TREE;
6639 tree gen_tmpl = NULL_TREE;
6641 tree tmpl = NULL_TREE;
6643 tree type = NULL_TREE;
6646 if (TREE_CODE (t) == TYPE_DECL)
6648 type = tsubst (TREE_TYPE (t), args, complain, in_decl);
6649 if (TREE_CODE (type) == TEMPLATE_TEMPLATE_PARM
6650 || t == TYPE_MAIN_DECL (TREE_TYPE (t)))
6652 /* If this is the canonical decl, we don't have to
6653 mess with instantiations, and often we can't (for
6654 typename, template type parms and such). Note that
6655 TYPE_NAME is not correct for the above test if
6656 we've copied the type for a typedef. */
6657 r = TYPE_NAME (type);
6662 /* Assume this is a non-local variable. */
6665 if (TYPE_P (CP_DECL_CONTEXT (t)))
6666 ctx = tsubst_aggr_type (DECL_CONTEXT (t), args,
6668 in_decl, /*entering_scope=*/1);
6669 else if (DECL_NAMESPACE_SCOPE_P (t))
6670 ctx = DECL_CONTEXT (t);
6673 /* Subsequent calls to pushdecl will fill this in. */
6678 /* Check to see if we already have this specialization. */
6681 tmpl = DECL_TI_TEMPLATE (t);
6682 gen_tmpl = most_general_template (tmpl);
6683 argvec = tsubst (DECL_TI_ARGS (t), args, complain, in_decl);
6684 spec = retrieve_specialization (gen_tmpl, argvec,
6685 /*class_specializations_p=*/false);
6688 spec = retrieve_local_specialization (t);
6697 if (TREE_CODE (r) == VAR_DECL)
6699 /* Even if the original location is out of scope, the
6700 newly substituted one is not. */
6701 DECL_DEAD_FOR_LOCAL (r) = 0;
6702 DECL_INITIALIZED_P (r) = 0;
6703 DECL_TEMPLATE_INSTANTIATED (r) = 0;
6704 type = tsubst (TREE_TYPE (t), args, complain, in_decl);
6705 if (type == error_mark_node)
6706 return error_mark_node;
6707 type = complete_type (type);
6708 DECL_INITIALIZED_BY_CONSTANT_EXPRESSION_P (r)
6709 = DECL_INITIALIZED_BY_CONSTANT_EXPRESSION_P (t);
6710 type = check_var_type (DECL_NAME (r), type);
6712 if (DECL_HAS_VALUE_EXPR_P (t))
6714 tree ve = DECL_VALUE_EXPR (t);
6715 ve = tsubst_expr (ve, args, complain, in_decl);
6716 SET_DECL_VALUE_EXPR (r, ve);
6719 else if (DECL_SELF_REFERENCE_P (t))
6720 SET_DECL_SELF_REFERENCE_P (r);
6721 TREE_TYPE (r) = type;
6722 cp_apply_type_quals_to_decl (cp_type_quals (type), r);
6723 DECL_CONTEXT (r) = ctx;
6724 /* Clear out the mangled name and RTL for the instantiation. */
6725 SET_DECL_ASSEMBLER_NAME (r, NULL_TREE);
6726 if (CODE_CONTAINS_STRUCT (TREE_CODE (t), TS_DECL_WRTL))
6727 SET_DECL_RTL (r, NULL_RTX);
6728 /* The initializer must not be expanded until it is required;
6730 DECL_INITIAL (r) = NULL_TREE;
6731 if (CODE_CONTAINS_STRUCT (TREE_CODE (t), TS_DECL_WRTL))
6732 SET_DECL_RTL (r, NULL_RTX);
6733 DECL_SIZE (r) = DECL_SIZE_UNIT (r) = 0;
6737 /* A static data member declaration is always marked
6738 external when it is declared in-class, even if an
6739 initializer is present. We mimic the non-template
6741 DECL_EXTERNAL (r) = 1;
6743 register_specialization (r, gen_tmpl, argvec, false);
6744 DECL_TEMPLATE_INFO (r) = tree_cons (tmpl, argvec, NULL_TREE);
6745 SET_DECL_IMPLICIT_INSTANTIATION (r);
6748 register_local_specialization (r, t);
6750 TREE_CHAIN (r) = NULL_TREE;
6759 /* Restore the file and line information. */
6760 input_location = saved_loc;
6765 /* Substitute into the ARG_TYPES of a function type. */
6768 tsubst_arg_types (tree arg_types,
6770 tsubst_flags_t complain,
6773 tree remaining_arg_types;
6776 tree result = NULL_TREE;
6778 if (!arg_types || arg_types == void_list_node)
6781 remaining_arg_types = tsubst_arg_types (TREE_CHAIN (arg_types),
6782 args, complain, in_decl);
6783 if (remaining_arg_types == error_mark_node)
6784 return error_mark_node;
6786 type = tsubst (TREE_VALUE (arg_types), args, complain, in_decl);
6787 if (type == error_mark_node)
6788 return error_mark_node;
6789 if (VOID_TYPE_P (type))
6791 if (complain & tf_error)
6793 error ("invalid parameter type %qT", type);
6795 error ("in declaration %q+D", in_decl);
6797 return error_mark_node;
6800 /* Do array-to-pointer, function-to-pointer conversion, and ignore
6801 top-level qualifiers as required. */
6802 type = TYPE_MAIN_VARIANT (type_decays_to (type));
6804 /* We do not substitute into default arguments here. The standard
6805 mandates that they be instantiated only when needed, which is
6806 done in build_over_call. */
6807 default_arg = TREE_PURPOSE (arg_types);
6809 if (default_arg && TREE_CODE (default_arg) == DEFAULT_ARG)
6811 /* We've instantiated a template before its default arguments
6812 have been parsed. This can happen for a nested template
6813 class, and is not an error unless we require the default
6814 argument in a call of this function. */
6815 result = tree_cons (default_arg, type, remaining_arg_types);
6816 VEC_safe_push (tree, gc, DEFARG_INSTANTIATIONS (default_arg), result);
6819 result = hash_tree_cons (default_arg, type, remaining_arg_types);
6824 /* Substitute into a FUNCTION_TYPE or METHOD_TYPE. This routine does
6825 *not* handle the exception-specification for FNTYPE, because the
6826 initial substitution of explicitly provided template parameters
6827 during argument deduction forbids substitution into the
6828 exception-specification:
6832 All references in the function type of the function template to the
6833 corresponding template parameters are replaced by the specified tem-
6834 plate argument values. If a substitution in a template parameter or
6835 in the function type of the function template results in an invalid
6836 type, type deduction fails. [Note: The equivalent substitution in
6837 exception specifications is done only when the function is instanti-
6838 ated, at which point a program is ill-formed if the substitution
6839 results in an invalid type.] */
6842 tsubst_function_type (tree t,
6844 tsubst_flags_t complain,
6851 /* The TYPE_CONTEXT is not used for function/method types. */
6852 gcc_assert (TYPE_CONTEXT (t) == NULL_TREE);
6854 /* Substitute the return type. */
6855 return_type = tsubst (TREE_TYPE (t), args, complain, in_decl);
6856 if (return_type == error_mark_node)
6857 return error_mark_node;
6858 /* The standard does not presently indicate that creation of a
6859 function type with an invalid return type is a deduction failure.
6860 However, that is clearly analogous to creating an array of "void"
6861 or a reference to a reference. This is core issue #486. */
6862 if (TREE_CODE (return_type) == ARRAY_TYPE
6863 || TREE_CODE (return_type) == FUNCTION_TYPE)
6865 if (complain & tf_error)
6867 if (TREE_CODE (return_type) == ARRAY_TYPE)
6868 error ("function returning an array");
6870 error ("function returning a function");
6872 return error_mark_node;
6875 /* Substitute the argument types. */
6876 arg_types = tsubst_arg_types (TYPE_ARG_TYPES (t), args,
6878 if (arg_types == error_mark_node)
6879 return error_mark_node;
6881 /* Construct a new type node and return it. */
6882 if (TREE_CODE (t) == FUNCTION_TYPE)
6883 fntype = build_function_type (return_type, arg_types);
6886 tree r = TREE_TYPE (TREE_VALUE (arg_types));
6887 if (! IS_AGGR_TYPE (r))
6891 Type deduction may fail for any of the following
6894 -- Attempting to create "pointer to member of T" when T
6895 is not a class type. */
6896 if (complain & tf_error)
6897 error ("creating pointer to member function of non-class type %qT",
6899 return error_mark_node;
6902 fntype = build_method_type_directly (r, return_type,
6903 TREE_CHAIN (arg_types));
6905 fntype = cp_build_qualified_type_real (fntype, TYPE_QUALS (t), complain);
6906 fntype = cp_build_type_attribute_variant (fntype, TYPE_ATTRIBUTES (t));
6911 /* FNTYPE is a FUNCTION_TYPE or METHOD_TYPE. Substitute the template
6912 ARGS into that specification, and return the substituted
6913 specification. If there is no specification, return NULL_TREE. */
6916 tsubst_exception_specification (tree fntype,
6918 tsubst_flags_t complain,
6924 specs = TYPE_RAISES_EXCEPTIONS (fntype);
6925 new_specs = NULL_TREE;
6928 if (! TREE_VALUE (specs))
6934 spec = tsubst (TREE_VALUE (specs), args, complain, in_decl);
6935 if (spec == error_mark_node)
6937 new_specs = add_exception_specifier (new_specs, spec, complain);
6938 specs = TREE_CHAIN (specs);
6944 /* Substitute into the PARMS of a call-declarator. */
6947 tsubst_call_declarator_parms (tree parms,
6949 tsubst_flags_t complain,
6956 if (!parms || parms == void_list_node)
6959 new_parms = tsubst_call_declarator_parms (TREE_CHAIN (parms),
6960 args, complain, in_decl);
6962 /* Figure out the type of this parameter. */
6963 type = tsubst (TREE_VALUE (parms), args, complain, in_decl);
6965 /* Figure out the default argument as well. Note that we use
6966 tsubst_expr since the default argument is really an expression. */
6967 defarg = tsubst_expr (TREE_PURPOSE (parms), args, complain, in_decl);
6969 /* Chain this parameter on to the front of those we have already
6970 processed. We don't use hash_tree_cons because that function
6971 doesn't check TREE_PARMLIST. */
6972 new_parms = tree_cons (defarg, type, new_parms);
6977 /* Take the tree structure T and replace template parameters used
6978 therein with the argument vector ARGS. IN_DECL is an associated
6979 decl for diagnostics. If an error occurs, returns ERROR_MARK_NODE.
6980 Issue error and warning messages under control of COMPLAIN. Note
6981 that we must be relatively non-tolerant of extensions here, in
6982 order to preserve conformance; if we allow substitutions that
6983 should not be allowed, we may allow argument deductions that should
6984 not succeed, and therefore report ambiguous overload situations
6985 where there are none. In theory, we could allow the substitution,
6986 but indicate that it should have failed, and allow our caller to
6987 make sure that the right thing happens, but we don't try to do this
6990 This function is used for dealing with types, decls and the like;
6991 for expressions, use tsubst_expr or tsubst_copy. */
6994 tsubst (tree t, tree args, tsubst_flags_t complain, tree in_decl)
6998 if (t == NULL_TREE || t == error_mark_node
6999 || t == integer_type_node
7000 || t == void_type_node
7001 || t == char_type_node
7002 || t == unknown_type_node
7003 || TREE_CODE (t) == NAMESPACE_DECL)
7007 return tsubst_decl (t, args, complain);
7009 if (TREE_CODE (t) == IDENTIFIER_NODE)
7010 type = IDENTIFIER_TYPE_VALUE (t);
7012 type = TREE_TYPE (t);
7014 gcc_assert (type != unknown_type_node);
7017 && TREE_CODE (t) != TYPENAME_TYPE
7018 && TREE_CODE (t) != IDENTIFIER_NODE
7019 && TREE_CODE (t) != FUNCTION_TYPE
7020 && TREE_CODE (t) != METHOD_TYPE)
7021 type = tsubst (type, args, complain, in_decl);
7022 if (type == error_mark_node)
7023 return error_mark_node;
7025 switch (TREE_CODE (t))
7030 return tsubst_aggr_type (t, args, complain, in_decl,
7031 /*entering_scope=*/0);
7034 case IDENTIFIER_NODE:
7046 if (t == integer_type_node)
7049 if (TREE_CODE (TYPE_MIN_VALUE (t)) == INTEGER_CST
7050 && TREE_CODE (TYPE_MAX_VALUE (t)) == INTEGER_CST)
7054 tree max, omax = TREE_OPERAND (TYPE_MAX_VALUE (t), 0);
7056 /* The array dimension behaves like a non-type template arg,
7057 in that we want to fold it as much as possible. */
7058 max = tsubst_template_arg (omax, args, complain, in_decl);
7059 max = fold_decl_constant_value (max);
7061 if (integer_zerop (omax))
7063 /* Still allow an explicit array of size zero. */
7065 pedwarn ("creating array with size zero");
7067 else if (integer_zerop (max)
7068 || (TREE_CODE (max) == INTEGER_CST
7069 && INT_CST_LT (max, integer_zero_node)))
7073 Type deduction may fail for any of the following
7076 Attempting to create an array with a size that is
7077 zero or negative. */
7078 if (complain & tf_error)
7079 error ("creating array with size zero (%qE)", max);
7081 return error_mark_node;
7084 return compute_array_index_type (NULL_TREE, max);
7087 case TEMPLATE_TYPE_PARM:
7088 case TEMPLATE_TEMPLATE_PARM:
7089 case BOUND_TEMPLATE_TEMPLATE_PARM:
7090 case TEMPLATE_PARM_INDEX:
7095 tree arg = NULL_TREE;
7099 gcc_assert (TREE_VEC_LENGTH (args) > 0);
7100 if (TREE_CODE (t) == TEMPLATE_TYPE_PARM
7101 || TREE_CODE (t) == TEMPLATE_TEMPLATE_PARM
7102 || TREE_CODE (t) == BOUND_TEMPLATE_TEMPLATE_PARM)
7104 idx = TEMPLATE_TYPE_IDX (t);
7105 level = TEMPLATE_TYPE_LEVEL (t);
7109 idx = TEMPLATE_PARM_IDX (t);
7110 level = TEMPLATE_PARM_LEVEL (t);
7113 levels = TMPL_ARGS_DEPTH (args);
7114 if (level <= levels)
7115 arg = TMPL_ARG (args, level, idx);
7117 if (arg == error_mark_node)
7118 return error_mark_node;
7119 else if (arg != NULL_TREE)
7121 if (TREE_CODE (t) == TEMPLATE_TYPE_PARM)
7123 gcc_assert (TYPE_P (arg));
7124 return cp_build_qualified_type_real
7125 (arg, cp_type_quals (arg) | cp_type_quals (t),
7126 complain | tf_ignore_bad_quals);
7128 else if (TREE_CODE (t) == BOUND_TEMPLATE_TEMPLATE_PARM)
7130 /* We are processing a type constructed from a
7131 template template parameter. */
7132 tree argvec = tsubst (TYPE_TI_ARGS (t),
7133 args, complain, in_decl);
7134 if (argvec == error_mark_node)
7135 return error_mark_node;
7137 /* We can get a TEMPLATE_TEMPLATE_PARM here when we
7138 are resolving nested-types in the signature of a
7139 member function templates. Otherwise ARG is a
7140 TEMPLATE_DECL and is the real template to be
7142 if (TREE_CODE (arg) == TEMPLATE_TEMPLATE_PARM)
7143 arg = TYPE_NAME (arg);
7145 r = lookup_template_class (arg,
7148 /*entering_scope=*/0,
7150 return cp_build_qualified_type_real
7151 (r, TYPE_QUALS (t), complain);
7154 /* TEMPLATE_TEMPLATE_PARM or TEMPLATE_PARM_INDEX. */
7159 /* This can happen during the attempted tsubst'ing in
7160 unify. This means that we don't yet have any information
7161 about the template parameter in question. */
7164 /* If we get here, we must have been looking at a parm for a
7165 more deeply nested template. Make a new version of this
7166 template parameter, but with a lower level. */
7167 switch (TREE_CODE (t))
7169 case TEMPLATE_TYPE_PARM:
7170 case TEMPLATE_TEMPLATE_PARM:
7171 case BOUND_TEMPLATE_TEMPLATE_PARM:
7172 if (cp_type_quals (t))
7174 r = tsubst (TYPE_MAIN_VARIANT (t), args, complain, in_decl);
7175 r = cp_build_qualified_type_real
7176 (r, cp_type_quals (t),
7177 complain | (TREE_CODE (t) == TEMPLATE_TYPE_PARM
7178 ? tf_ignore_bad_quals : 0));
7183 TEMPLATE_TYPE_PARM_INDEX (r)
7184 = reduce_template_parm_level (TEMPLATE_TYPE_PARM_INDEX (t),
7186 TYPE_STUB_DECL (r) = TYPE_NAME (r) = TEMPLATE_TYPE_DECL (r);
7187 TYPE_MAIN_VARIANT (r) = r;
7188 TYPE_POINTER_TO (r) = NULL_TREE;
7189 TYPE_REFERENCE_TO (r) = NULL_TREE;
7191 if (TREE_CODE (t) == BOUND_TEMPLATE_TEMPLATE_PARM)
7193 tree argvec = tsubst (TYPE_TI_ARGS (t), args,
7195 if (argvec == error_mark_node)
7196 return error_mark_node;
7198 TEMPLATE_TEMPLATE_PARM_TEMPLATE_INFO (r)
7199 = tree_cons (TYPE_TI_TEMPLATE (t), argvec, NULL_TREE);
7204 case TEMPLATE_PARM_INDEX:
7205 r = reduce_template_parm_level (t, type, levels);
7217 tree purpose, value, chain;
7219 if (t == void_list_node)
7222 purpose = TREE_PURPOSE (t);
7225 purpose = tsubst (purpose, args, complain, in_decl);
7226 if (purpose == error_mark_node)
7227 return error_mark_node;
7229 value = TREE_VALUE (t);
7232 value = tsubst (value, args, complain, in_decl);
7233 if (value == error_mark_node)
7234 return error_mark_node;
7236 chain = TREE_CHAIN (t);
7237 if (chain && chain != void_type_node)
7239 chain = tsubst (chain, args, complain, in_decl);
7240 if (chain == error_mark_node)
7241 return error_mark_node;
7243 if (purpose == TREE_PURPOSE (t)
7244 && value == TREE_VALUE (t)
7245 && chain == TREE_CHAIN (t))
7247 return hash_tree_cons (purpose, value, chain);
7251 /* We should never be tsubsting a binfo. */
7255 /* A vector of template arguments. */
7257 return tsubst_template_args (t, args, complain, in_decl);
7260 case REFERENCE_TYPE:
7262 enum tree_code code;
7264 if (type == TREE_TYPE (t) && TREE_CODE (type) != METHOD_TYPE)
7267 code = TREE_CODE (t);
7272 Type deduction may fail for any of the following
7275 -- Attempting to create a pointer to reference type.
7276 -- Attempting to create a reference to a reference type or
7277 a reference to void. */
7278 if (TREE_CODE (type) == REFERENCE_TYPE
7279 || (code == REFERENCE_TYPE && TREE_CODE (type) == VOID_TYPE))
7281 static location_t last_loc;
7283 /* We keep track of the last time we issued this error
7284 message to avoid spewing a ton of messages during a
7285 single bad template instantiation. */
7286 if (complain & tf_error
7287 #ifdef USE_MAPPED_LOCATION
7288 && last_loc != input_location
7290 && (last_loc.line != input_line
7291 || last_loc.file != input_filename)
7295 if (TREE_CODE (type) == VOID_TYPE)
7296 error ("forming reference to void");
7298 error ("forming %s to reference type %qT",
7299 (code == POINTER_TYPE) ? "pointer" : "reference",
7301 last_loc = input_location;
7304 return error_mark_node;
7306 else if (code == POINTER_TYPE)
7308 r = build_pointer_type (type);
7309 if (TREE_CODE (type) == METHOD_TYPE)
7310 r = build_ptrmemfunc_type (r);
7313 r = build_reference_type (type);
7314 r = cp_build_qualified_type_real (r, TYPE_QUALS (t), complain);
7316 if (r != error_mark_node)
7317 /* Will this ever be needed for TYPE_..._TO values? */
7324 r = tsubst (TYPE_OFFSET_BASETYPE (t), args, complain, in_decl);
7325 if (r == error_mark_node || !IS_AGGR_TYPE (r))
7329 Type deduction may fail for any of the following
7332 -- Attempting to create "pointer to member of T" when T
7333 is not a class type. */
7334 if (complain & tf_error)
7335 error ("creating pointer to member of non-class type %qT", r);
7336 return error_mark_node;
7338 if (TREE_CODE (type) == REFERENCE_TYPE)
7340 if (complain & tf_error)
7341 error ("creating pointer to member reference type %qT", type);
7342 return error_mark_node;
7344 if (TREE_CODE (type) == VOID_TYPE)
7346 if (complain & tf_error)
7347 error ("creating pointer to member of type void");
7348 return error_mark_node;
7350 gcc_assert (TREE_CODE (type) != METHOD_TYPE);
7351 if (TREE_CODE (type) == FUNCTION_TYPE)
7353 /* The type of the implicit object parameter gets its
7354 cv-qualifiers from the FUNCTION_TYPE. */
7356 tree this_type = cp_build_qualified_type (TYPE_MAIN_VARIANT (r),
7357 cp_type_quals (type));
7359 method_type = build_method_type_directly (this_type,
7361 TYPE_ARG_TYPES (type));
7362 memptr = build_ptrmemfunc_type (build_pointer_type (method_type));
7363 return cp_build_qualified_type_real (memptr, cp_type_quals (t),
7367 return cp_build_qualified_type_real (build_ptrmem_type (r, type),
7376 fntype = tsubst_function_type (t, args, complain, in_decl);
7377 if (fntype == error_mark_node)
7378 return error_mark_node;
7380 /* Substitute the exception specification. */
7381 specs = tsubst_exception_specification (t, args, complain,
7383 if (specs == error_mark_node)
7384 return error_mark_node;
7386 fntype = build_exception_variant (fntype, specs);
7391 tree domain = tsubst (TYPE_DOMAIN (t), args, complain, in_decl);
7392 if (domain == error_mark_node)
7393 return error_mark_node;
7395 /* As an optimization, we avoid regenerating the array type if
7396 it will obviously be the same as T. */
7397 if (type == TREE_TYPE (t) && domain == TYPE_DOMAIN (t))
7400 /* These checks should match the ones in grokdeclarator.
7404 The deduction may fail for any of the following reasons:
7406 -- Attempting to create an array with an element type that
7407 is void, a function type, or a reference type, or [DR337]
7408 an abstract class type. */
7409 if (TREE_CODE (type) == VOID_TYPE
7410 || TREE_CODE (type) == FUNCTION_TYPE
7411 || TREE_CODE (type) == REFERENCE_TYPE)
7413 if (complain & tf_error)
7414 error ("creating array of %qT", type);
7415 return error_mark_node;
7417 if (CLASS_TYPE_P (type) && CLASSTYPE_PURE_VIRTUALS (type))
7419 if (complain & tf_error)
7420 error ("creating array of %qT, which is an abstract class type",
7422 return error_mark_node;
7425 r = build_cplus_array_type (type, domain);
7432 tree e1 = tsubst (TREE_OPERAND (t, 0), args, complain, in_decl);
7433 tree e2 = tsubst (TREE_OPERAND (t, 1), args, complain, in_decl);
7435 if (e1 == error_mark_node || e2 == error_mark_node)
7436 return error_mark_node;
7438 return fold_build2 (TREE_CODE (t), TREE_TYPE (t), e1, e2);
7444 tree e = tsubst (TREE_OPERAND (t, 0), args, complain, in_decl);
7445 if (e == error_mark_node)
7446 return error_mark_node;
7448 return fold_build1 (TREE_CODE (t), TREE_TYPE (t), e);
7453 tree ctx = tsubst_aggr_type (TYPE_CONTEXT (t), args, complain,
7454 in_decl, /*entering_scope=*/1);
7455 tree f = tsubst_copy (TYPENAME_TYPE_FULLNAME (t), args,
7458 if (ctx == error_mark_node || f == error_mark_node)
7459 return error_mark_node;
7461 if (!IS_AGGR_TYPE (ctx))
7463 if (complain & tf_error)
7464 error ("%qT is not a class, struct, or union type", ctx);
7465 return error_mark_node;
7467 else if (!uses_template_parms (ctx) && !TYPE_BEING_DEFINED (ctx))
7469 /* Normally, make_typename_type does not require that the CTX
7470 have complete type in order to allow things like:
7472 template <class T> struct S { typename S<T>::X Y; };
7474 But, such constructs have already been resolved by this
7475 point, so here CTX really should have complete type, unless
7476 it's a partial instantiation. */
7477 ctx = complete_type (ctx);
7478 if (!COMPLETE_TYPE_P (ctx))
7480 if (complain & tf_error)
7481 cxx_incomplete_type_error (NULL_TREE, ctx);
7482 return error_mark_node;
7486 f = make_typename_type (ctx, f, typename_type,
7487 (complain & tf_error) | tf_keep_type_decl);
7488 if (f == error_mark_node)
7490 if (TREE_CODE (f) == TYPE_DECL)
7492 complain |= tf_ignore_bad_quals;
7496 if (TREE_CODE (f) != TYPENAME_TYPE)
7498 if (TYPENAME_IS_ENUM_P (t) && TREE_CODE (f) != ENUMERAL_TYPE)
7499 error ("%qT resolves to %qT, which is not an enumeration type",
7501 else if (TYPENAME_IS_CLASS_P (t) && !CLASS_TYPE_P (f))
7502 error ("%qT resolves to %qT, which is is not a class type",
7506 return cp_build_qualified_type_real
7507 (f, cp_type_quals (f) | cp_type_quals (t), complain);
7510 case UNBOUND_CLASS_TEMPLATE:
7512 tree ctx = tsubst_aggr_type (TYPE_CONTEXT (t), args, complain,
7513 in_decl, /*entering_scope=*/1);
7514 tree name = TYPE_IDENTIFIER (t);
7515 tree parm_list = DECL_TEMPLATE_PARMS (TYPE_NAME (t));
7517 if (ctx == error_mark_node || name == error_mark_node)
7518 return error_mark_node;
7521 parm_list = tsubst_template_parms (parm_list, args, complain);
7522 return make_unbound_class_template (ctx, name, parm_list, complain);
7532 tree e1 = tsubst (TREE_OPERAND (t, 0), args, complain, in_decl);
7533 tree e2 = tsubst_expr (TREE_OPERAND (t, 1), args, complain, in_decl);
7534 if (e1 == error_mark_node || e2 == error_mark_node)
7535 return error_mark_node;
7537 return build_nt (ARRAY_REF, e1, e2, NULL_TREE, NULL_TREE);
7542 tree e1 = tsubst (TREE_OPERAND (t, 0), args, complain, in_decl);
7543 tree e2 = tsubst (TREE_OPERAND (t, 1), args, complain, in_decl);
7544 if (e1 == error_mark_node || e2 == error_mark_node)
7545 return error_mark_node;
7547 return build_qualified_name (/*type=*/NULL_TREE,
7548 e1, e2, QUALIFIED_NAME_IS_TEMPLATE (t));
7555 type = finish_typeof (tsubst_expr (TYPEOF_TYPE_EXPR (t), args,
7556 complain, in_decl));
7557 return cp_build_qualified_type_real (type,
7559 | cp_type_quals (type),
7564 sorry ("use of %qs in template",
7565 tree_code_name [(int) TREE_CODE (t)]);
7566 return error_mark_node;
7570 /* Like tsubst_expr for a BASELINK. OBJECT_TYPE, if non-NULL, is the
7571 type of the expression on the left-hand side of the "." or "->"
7575 tsubst_baselink (tree baselink, tree object_type,
7576 tree args, tsubst_flags_t complain, tree in_decl)
7579 tree qualifying_scope;
7581 tree template_args = 0;
7582 bool template_id_p = false;
7584 /* A baselink indicates a function from a base class. The
7585 BASELINK_ACCESS_BINFO and BASELINK_BINFO are going to have
7586 non-dependent types; otherwise, the lookup could not have
7587 succeeded. However, they may indicate bases of the template
7588 class, rather than the instantiated class.
7590 In addition, lookups that were not ambiguous before may be
7591 ambiguous now. Therefore, we perform the lookup again. */
7592 qualifying_scope = BINFO_TYPE (BASELINK_ACCESS_BINFO (baselink));
7593 fns = BASELINK_FUNCTIONS (baselink);
7594 if (TREE_CODE (fns) == TEMPLATE_ID_EXPR)
7596 template_id_p = true;
7597 template_args = TREE_OPERAND (fns, 1);
7598 fns = TREE_OPERAND (fns, 0);
7600 template_args = tsubst_template_args (template_args, args,
7603 name = DECL_NAME (get_first_fn (fns));
7604 baselink = lookup_fnfields (qualifying_scope, name, /*protect=*/1);
7606 /* If lookup found a single function, mark it as used at this
7607 point. (If it lookup found multiple functions the one selected
7608 later by overload resolution will be marked as used at that
7610 if (BASELINK_P (baselink))
7611 fns = BASELINK_FUNCTIONS (baselink);
7612 if (!template_id_p && !really_overloaded_fn (fns))
7613 mark_used (OVL_CURRENT (fns));
7615 /* Add back the template arguments, if present. */
7616 if (BASELINK_P (baselink) && template_id_p)
7617 BASELINK_FUNCTIONS (baselink)
7618 = build_nt (TEMPLATE_ID_EXPR,
7619 BASELINK_FUNCTIONS (baselink),
7623 object_type = current_class_type;
7624 return adjust_result_of_qualified_name_lookup (baselink,
7629 /* Like tsubst_expr for a SCOPE_REF, given by QUALIFIED_ID. DONE is
7630 true if the qualified-id will be a postfix-expression in-and-of
7631 itself; false if more of the postfix-expression follows the
7632 QUALIFIED_ID. ADDRESS_P is true if the qualified-id is the operand
7636 tsubst_qualified_id (tree qualified_id, tree args,
7637 tsubst_flags_t complain, tree in_decl,
7638 bool done, bool address_p)
7646 gcc_assert (TREE_CODE (qualified_id) == SCOPE_REF);
7648 /* Figure out what name to look up. */
7649 name = TREE_OPERAND (qualified_id, 1);
7650 if (TREE_CODE (name) == TEMPLATE_ID_EXPR)
7653 template_args = TREE_OPERAND (name, 1);
7655 template_args = tsubst_template_args (template_args, args,
7657 name = TREE_OPERAND (name, 0);
7661 is_template = false;
7662 template_args = NULL_TREE;
7665 /* Substitute into the qualifying scope. When there are no ARGS, we
7666 are just trying to simplify a non-dependent expression. In that
7667 case the qualifying scope may be dependent, and, in any case,
7668 substituting will not help. */
7669 scope = TREE_OPERAND (qualified_id, 0);
7672 scope = tsubst (scope, args, complain, in_decl);
7673 expr = tsubst_copy (name, args, complain, in_decl);
7678 if (dependent_type_p (scope))
7679 return build_qualified_name (/*type=*/NULL_TREE,
7681 QUALIFIED_NAME_IS_TEMPLATE (qualified_id));
7683 if (!BASELINK_P (name) && !DECL_P (expr))
7685 if (TREE_CODE (expr) == BIT_NOT_EXPR)
7686 /* If this were actually a destructor call, it would have been
7687 parsed as such by the parser. */
7688 expr = error_mark_node;
7690 expr = lookup_qualified_name (scope, expr, /*is_type_p=*/0, false);
7691 if (TREE_CODE (TREE_CODE (expr) == TEMPLATE_DECL
7692 ? DECL_TEMPLATE_RESULT (expr) : expr) == TYPE_DECL)
7694 if (complain & tf_error)
7696 error ("dependent-name %qE is parsed as a non-type, but "
7697 "instantiation yields a type", qualified_id);
7698 inform ("say %<typename %E%> if a type is meant", qualified_id);
7700 return error_mark_node;
7706 check_accessibility_of_qualified_id (expr, /*object_type=*/NULL_TREE,
7708 /* Remember that there was a reference to this entity. */
7712 if (expr == error_mark_node || TREE_CODE (expr) == TREE_LIST)
7714 if (complain & tf_error)
7715 qualified_name_lookup_error (scope,
7716 TREE_OPERAND (qualified_id, 1),
7718 return error_mark_node;
7722 expr = lookup_template_function (expr, template_args);
7724 if (expr == error_mark_node && complain & tf_error)
7725 qualified_name_lookup_error (scope, TREE_OPERAND (qualified_id, 1),
7727 else if (TYPE_P (scope))
7729 expr = (adjust_result_of_qualified_name_lookup
7730 (expr, scope, current_class_type));
7731 expr = (finish_qualified_id_expr
7732 (scope, expr, done, address_p,
7733 QUALIFIED_NAME_IS_TEMPLATE (qualified_id),
7734 /*template_arg_p=*/false));
7737 if (TREE_CODE (expr) != SCOPE_REF)
7738 expr = convert_from_reference (expr);
7743 /* Like tsubst, but deals with expressions. This function just replaces
7744 template parms; to finish processing the resultant expression, use
7748 tsubst_copy (tree t, tree args, tsubst_flags_t complain, tree in_decl)
7750 enum tree_code code;
7753 if (t == NULL_TREE || t == error_mark_node)
7756 code = TREE_CODE (t);
7761 r = retrieve_local_specialization (t);
7762 gcc_assert (r != NULL);
7771 if (DECL_TEMPLATE_PARM_P (t))
7772 return tsubst_copy (DECL_INITIAL (t), args, complain, in_decl);
7773 /* There is no need to substitute into namespace-scope
7775 if (DECL_NAMESPACE_SCOPE_P (t))
7777 /* If ARGS is NULL, then T is known to be non-dependent. */
7778 if (args == NULL_TREE)
7779 return integral_constant_value (t);
7781 /* Unfortunately, we cannot just call lookup_name here.
7784 template <int I> int f() {
7786 struct S { void g() { E e = a; } };
7789 When we instantiate f<7>::S::g(), say, lookup_name is not
7790 clever enough to find f<7>::a. */
7792 = tsubst_aggr_type (TREE_TYPE (t), args, complain, in_decl,
7793 /*entering_scope=*/0);
7795 for (v = TYPE_VALUES (enum_type);
7798 if (TREE_PURPOSE (v) == DECL_NAME (t))
7799 return TREE_VALUE (v);
7801 /* We didn't find the name. That should never happen; if
7802 name-lookup found it during preliminary parsing, we
7803 should find it again here during instantiation. */
7809 if (DECL_CONTEXT (t))
7813 ctx = tsubst_aggr_type (DECL_CONTEXT (t), args, complain, in_decl,
7814 /*entering_scope=*/1);
7815 if (ctx != DECL_CONTEXT (t))
7817 tree r = lookup_field (ctx, DECL_NAME (t), 0, false);
7820 if (complain & tf_error)
7821 error ("using invalid field %qD", t);
7822 return error_mark_node;
7832 if ((DECL_LANG_SPECIFIC (t) && DECL_TEMPLATE_INFO (t))
7833 || local_variable_p (t))
7834 t = tsubst (t, args, complain, in_decl);
7839 return tsubst_baselink (t, current_class_type, args, complain, in_decl);
7842 if (DECL_TEMPLATE_TEMPLATE_PARM_P (t))
7843 return tsubst (TREE_TYPE (DECL_TEMPLATE_RESULT (t)),
7844 args, complain, in_decl);
7845 else if (DECL_FUNCTION_TEMPLATE_P (t) && DECL_MEMBER_TEMPLATE_P (t))
7846 return tsubst (t, args, complain, in_decl);
7847 else if (DECL_CLASS_SCOPE_P (t)
7848 && uses_template_parms (DECL_CONTEXT (t)))
7850 /* Template template argument like the following example need
7853 template <template <class> class TT> struct C {};
7854 template <class T> struct D {
7855 template <class U> struct E {};
7860 We are processing the template argument `E' in #1 for
7861 the template instantiation #2. Originally, `E' is a
7862 TEMPLATE_DECL with `D<T>' as its DECL_CONTEXT. Now we
7863 have to substitute this with one having context `D<int>'. */
7865 tree context = tsubst (DECL_CONTEXT (t), args, complain, in_decl);
7866 return lookup_field (context, DECL_NAME(t), 0, false);
7869 /* Ordinary template template argument. */
7873 case REINTERPRET_CAST_EXPR:
7874 case CONST_CAST_EXPR:
7875 case STATIC_CAST_EXPR:
7876 case DYNAMIC_CAST_EXPR:
7879 (code, tsubst (TREE_TYPE (t), args, complain, in_decl),
7880 tsubst_copy (TREE_OPERAND (t, 0), args, complain, in_decl));
7884 case TRUTH_NOT_EXPR:
7887 case UNARY_PLUS_EXPR: /* Unary + */
7896 (code, tsubst (TREE_TYPE (t), args, complain, in_decl),
7897 tsubst_copy (TREE_OPERAND (t, 0), args, complain, in_decl));
7904 object = tsubst_copy (TREE_OPERAND (t, 0), args, complain, in_decl);
7905 name = TREE_OPERAND (t, 1);
7906 if (TREE_CODE (name) == BIT_NOT_EXPR)
7908 name = tsubst_copy (TREE_OPERAND (name, 0), args,
7910 name = build1 (BIT_NOT_EXPR, NULL_TREE, name);
7912 else if (TREE_CODE (name) == SCOPE_REF
7913 && TREE_CODE (TREE_OPERAND (name, 1)) == BIT_NOT_EXPR)
7915 tree base = tsubst_copy (TREE_OPERAND (name, 0), args,
7917 name = TREE_OPERAND (name, 1);
7918 name = tsubst_copy (TREE_OPERAND (name, 0), args,
7920 name = build1 (BIT_NOT_EXPR, NULL_TREE, name);
7921 name = build_qualified_name (/*type=*/NULL_TREE,
7923 /*template_p=*/false);
7925 else if (TREE_CODE (name) == BASELINK)
7926 name = tsubst_baselink (name,
7927 non_reference (TREE_TYPE (object)),
7931 name = tsubst_copy (name, args, complain, in_decl);
7932 return build_nt (COMPONENT_REF, object, name, NULL_TREE);
7938 case TRUNC_DIV_EXPR:
7940 case FLOOR_DIV_EXPR:
7941 case ROUND_DIV_EXPR:
7942 case EXACT_DIV_EXPR:
7946 case TRUNC_MOD_EXPR:
7947 case FLOOR_MOD_EXPR:
7948 case TRUTH_ANDIF_EXPR:
7949 case TRUTH_ORIF_EXPR:
7950 case TRUTH_AND_EXPR:
7967 case PREDECREMENT_EXPR:
7968 case PREINCREMENT_EXPR:
7969 case POSTDECREMENT_EXPR:
7970 case POSTINCREMENT_EXPR:
7972 (code, tsubst_copy (TREE_OPERAND (t, 0), args, complain, in_decl),
7973 tsubst_copy (TREE_OPERAND (t, 1), args, complain, in_decl));
7976 return build_qualified_name (/*type=*/NULL_TREE,
7977 tsubst_copy (TREE_OPERAND (t, 0),
7978 args, complain, in_decl),
7979 tsubst_copy (TREE_OPERAND (t, 1),
7980 args, complain, in_decl),
7981 QUALIFIED_NAME_IS_TEMPLATE (t));
7986 tsubst_copy (TREE_OPERAND (t, 0), args, complain, in_decl),
7987 tsubst_copy (TREE_OPERAND (t, 1), args, complain, in_decl),
7988 NULL_TREE, NULL_TREE);
7991 return build_nt (code,
7992 tsubst_copy (TREE_OPERAND (t, 0), args,
7994 tsubst_copy (TREE_OPERAND (t, 1), args, complain,
8000 case PSEUDO_DTOR_EXPR:
8003 (code, tsubst_copy (TREE_OPERAND (t, 0), args, complain, in_decl),
8004 tsubst_copy (TREE_OPERAND (t, 1), args, complain, in_decl),
8005 tsubst_copy (TREE_OPERAND (t, 2), args, complain, in_decl));
8006 TREE_NO_WARNING (r) = TREE_NO_WARNING (t);
8013 (code, tsubst_copy (TREE_OPERAND (t, 0), args, complain, in_decl),
8014 tsubst_copy (TREE_OPERAND (t, 1), args, complain, in_decl),
8015 tsubst_copy (TREE_OPERAND (t, 2), args, complain, in_decl));
8016 NEW_EXPR_USE_GLOBAL (r) = NEW_EXPR_USE_GLOBAL (t);
8023 (code, tsubst_copy (TREE_OPERAND (t, 0), args, complain, in_decl),
8024 tsubst_copy (TREE_OPERAND (t, 1), args, complain, in_decl));
8025 DELETE_EXPR_USE_GLOBAL (r) = DELETE_EXPR_USE_GLOBAL (t);
8026 DELETE_EXPR_USE_VEC (r) = DELETE_EXPR_USE_VEC (t);
8030 case TEMPLATE_ID_EXPR:
8032 /* Substituted template arguments */
8033 tree fn = TREE_OPERAND (t, 0);
8034 tree targs = TREE_OPERAND (t, 1);
8036 fn = tsubst_copy (fn, args, complain, in_decl);
8038 targs = tsubst_template_args (targs, args, complain, in_decl);
8040 return lookup_template_function (fn, targs);
8045 tree purpose, value, chain;
8047 if (t == void_list_node)
8050 purpose = TREE_PURPOSE (t);
8052 purpose = tsubst_copy (purpose, args, complain, in_decl);
8053 value = TREE_VALUE (t);
8055 value = tsubst_copy (value, args, complain, in_decl);
8056 chain = TREE_CHAIN (t);
8057 if (chain && chain != void_type_node)
8058 chain = tsubst_copy (chain, args, complain, in_decl);
8059 if (purpose == TREE_PURPOSE (t)
8060 && value == TREE_VALUE (t)
8061 && chain == TREE_CHAIN (t))
8063 return tree_cons (purpose, value, chain);
8070 case TEMPLATE_TYPE_PARM:
8071 case TEMPLATE_TEMPLATE_PARM:
8072 case BOUND_TEMPLATE_TEMPLATE_PARM:
8073 case TEMPLATE_PARM_INDEX:
8075 case REFERENCE_TYPE:
8081 case UNBOUND_CLASS_TEMPLATE:
8084 return tsubst (t, args, complain, in_decl);
8086 case IDENTIFIER_NODE:
8087 if (IDENTIFIER_TYPENAME_P (t))
8089 tree new_type = tsubst (TREE_TYPE (t), args, complain, in_decl);
8090 return mangle_conv_op_name_for_type (new_type);
8096 /* This is handled by tsubst_copy_and_build. */
8100 return build_x_va_arg (tsubst_copy (TREE_OPERAND (t, 0), args, complain,
8102 tsubst (TREE_TYPE (t), args, complain, in_decl));
8104 case CLEANUP_POINT_EXPR:
8105 /* We shouldn't have built any of these during initial template
8106 generation. Instead, they should be built during instantiation
8107 in response to the saved STMT_IS_FULL_EXPR_P setting. */
8115 /* Like tsubst_copy for expressions, etc. but also does semantic
8119 tsubst_expr (tree t, tree args, tsubst_flags_t complain, tree in_decl)
8123 if (t == NULL_TREE || t == error_mark_node)
8126 if (EXPR_HAS_LOCATION (t))
8127 input_location = EXPR_LOCATION (t);
8128 if (STATEMENT_CODE_P (TREE_CODE (t)))
8129 current_stmt_tree ()->stmts_are_full_exprs_p = STMT_IS_FULL_EXPR_P (t);
8131 switch (TREE_CODE (t))
8133 case STATEMENT_LIST:
8135 tree_stmt_iterator i;
8136 for (i = tsi_start (t); !tsi_end_p (i); tsi_next (&i))
8137 tsubst_expr (tsi_stmt (i), args, complain, in_decl);
8141 case CTOR_INITIALIZER:
8142 finish_mem_initializers (tsubst_initializer_list
8143 (TREE_OPERAND (t, 0), args));
8147 finish_return_stmt (tsubst_expr (TREE_OPERAND (t, 0),
8148 args, complain, in_decl));
8152 tmp = tsubst_expr (EXPR_STMT_EXPR (t), args, complain, in_decl);
8153 if (EXPR_STMT_STMT_EXPR_RESULT (t))
8154 finish_stmt_expr_expr (tmp, cur_stmt_expr);
8156 finish_expr_stmt (tmp);
8160 do_using_directive (tsubst_expr (USING_STMT_NAMESPACE (t),
8161 args, complain, in_decl));
8169 decl = DECL_EXPR_DECL (t);
8170 if (TREE_CODE (decl) == LABEL_DECL)
8171 finish_label_decl (DECL_NAME (decl));
8172 else if (TREE_CODE (decl) == USING_DECL)
8174 tree scope = USING_DECL_SCOPE (decl);
8175 tree name = DECL_NAME (decl);
8178 scope = tsubst_expr (scope, args, complain, in_decl);
8179 decl = lookup_qualified_name (scope, name,
8180 /*is_type_p=*/false,
8181 /*complain=*/false);
8182 if (decl == error_mark_node || TREE_CODE (decl) == TREE_LIST)
8183 qualified_name_lookup_error (scope, name, decl);
8185 do_local_using_decl (decl, scope, name);
8189 init = DECL_INITIAL (decl);
8190 decl = tsubst (decl, args, complain, in_decl);
8191 if (decl != error_mark_node)
8194 DECL_INITIAL (decl) = error_mark_node;
8195 /* By marking the declaration as instantiated, we avoid
8196 trying to instantiate it. Since instantiate_decl can't
8197 handle local variables, and since we've already done
8198 all that needs to be done, that's the right thing to
8200 if (TREE_CODE (decl) == VAR_DECL)
8201 DECL_TEMPLATE_INSTANTIATED (decl) = 1;
8202 if (TREE_CODE (decl) == VAR_DECL
8203 && ANON_AGGR_TYPE_P (TREE_TYPE (decl)))
8204 /* Anonymous aggregates are a special case. */
8205 finish_anon_union (decl);
8208 maybe_push_decl (decl);
8209 if (TREE_CODE (decl) == VAR_DECL
8210 && DECL_PRETTY_FUNCTION_P (decl))
8212 /* For __PRETTY_FUNCTION__ we have to adjust the
8214 const char *const name
8215 = cxx_printable_name (current_function_decl, 2);
8216 init = cp_fname_init (name, &TREE_TYPE (decl));
8219 init = tsubst_expr (init, args, complain, in_decl);
8220 cp_finish_decl (decl, init, NULL_TREE, 0);
8225 /* A DECL_EXPR can also be used as an expression, in the condition
8226 clause of an if/for/while construct. */
8231 stmt = begin_for_stmt ();
8232 tsubst_expr (FOR_INIT_STMT (t), args, complain, in_decl);
8233 finish_for_init_stmt (stmt);
8234 tmp = tsubst_expr (FOR_COND (t), args, complain, in_decl);
8235 finish_for_cond (tmp, stmt);
8236 tmp = tsubst_expr (FOR_EXPR (t), args, complain, in_decl);
8237 finish_for_expr (tmp, stmt);
8238 tsubst_expr (FOR_BODY (t), args, complain, in_decl);
8239 finish_for_stmt (stmt);
8243 stmt = begin_while_stmt ();
8244 tmp = tsubst_expr (WHILE_COND (t), args, complain, in_decl);
8245 finish_while_stmt_cond (tmp, stmt);
8246 tsubst_expr (WHILE_BODY (t), args, complain, in_decl);
8247 finish_while_stmt (stmt);
8251 stmt = begin_do_stmt ();
8252 tsubst_expr (DO_BODY (t), args, complain, in_decl);
8253 finish_do_body (stmt);
8254 tmp = tsubst_expr (DO_COND (t), args, complain, in_decl);
8255 finish_do_stmt (tmp, stmt);
8259 stmt = begin_if_stmt ();
8260 tmp = tsubst_expr (IF_COND (t), args, complain, in_decl);
8261 finish_if_stmt_cond (tmp, stmt);
8262 tsubst_expr (THEN_CLAUSE (t), args, complain, in_decl);
8263 finish_then_clause (stmt);
8265 if (ELSE_CLAUSE (t))
8267 begin_else_clause (stmt);
8268 tsubst_expr (ELSE_CLAUSE (t), args, complain, in_decl);
8269 finish_else_clause (stmt);
8272 finish_if_stmt (stmt);
8276 if (BIND_EXPR_BODY_BLOCK (t))
8277 stmt = begin_function_body ();
8279 stmt = begin_compound_stmt (BIND_EXPR_TRY_BLOCK (t)
8280 ? BCS_TRY_BLOCK : 0);
8282 tsubst_expr (BIND_EXPR_BODY (t), args, complain, in_decl);
8284 if (BIND_EXPR_BODY_BLOCK (t))
8285 finish_function_body (stmt);
8287 finish_compound_stmt (stmt);
8291 finish_break_stmt ();
8295 finish_continue_stmt ();
8299 stmt = begin_switch_stmt ();
8300 tmp = tsubst_expr (SWITCH_STMT_COND (t), args, complain, in_decl);
8301 finish_switch_cond (tmp, stmt);
8302 tsubst_expr (SWITCH_STMT_BODY (t), args, complain, in_decl);
8303 finish_switch_stmt (stmt);
8306 case CASE_LABEL_EXPR:
8307 finish_case_label (tsubst_expr (CASE_LOW (t), args, complain, in_decl),
8308 tsubst_expr (CASE_HIGH (t), args, complain,
8313 finish_label_stmt (DECL_NAME (LABEL_EXPR_LABEL (t)));
8317 tmp = GOTO_DESTINATION (t);
8318 if (TREE_CODE (tmp) != LABEL_DECL)
8319 /* Computed goto's must be tsubst'd into. On the other hand,
8320 non-computed gotos must not be; the identifier in question
8321 will have no binding. */
8322 tmp = tsubst_expr (tmp, args, complain, in_decl);
8324 tmp = DECL_NAME (tmp);
8325 finish_goto_stmt (tmp);
8329 tmp = finish_asm_stmt
8330 (ASM_VOLATILE_P (t),
8331 tsubst_expr (ASM_STRING (t), args, complain, in_decl),
8332 tsubst_expr (ASM_OUTPUTS (t), args, complain, in_decl),
8333 tsubst_expr (ASM_INPUTS (t), args, complain, in_decl),
8334 tsubst_expr (ASM_CLOBBERS (t), args, complain, in_decl));
8336 tree asm_expr = tmp;
8337 if (TREE_CODE (asm_expr) == CLEANUP_POINT_EXPR)
8338 asm_expr = TREE_OPERAND (asm_expr, 0);
8339 ASM_INPUT_P (asm_expr) = ASM_INPUT_P (t);
8346 stmt = begin_try_block ();
8347 tsubst_expr (TRY_STMTS (t), args, complain, in_decl);
8348 finish_cleanup_try_block (stmt);
8349 finish_cleanup (tsubst_expr (TRY_HANDLERS (t), args,
8355 if (FN_TRY_BLOCK_P (t))
8356 stmt = begin_function_try_block ();
8358 stmt = begin_try_block ();
8360 tsubst_expr (TRY_STMTS (t), args, complain, in_decl);
8362 if (FN_TRY_BLOCK_P (t))
8363 finish_function_try_block (stmt);
8365 finish_try_block (stmt);
8367 tsubst_expr (TRY_HANDLERS (t), args, complain, in_decl);
8368 if (FN_TRY_BLOCK_P (t))
8369 finish_function_handler_sequence (stmt);
8371 finish_handler_sequence (stmt);
8379 stmt = begin_handler ();
8380 if (HANDLER_PARMS (t))
8382 decl = HANDLER_PARMS (t);
8383 decl = tsubst (decl, args, complain, in_decl);
8384 /* Prevent instantiate_decl from trying to instantiate
8385 this variable. We've already done all that needs to be
8387 DECL_TEMPLATE_INSTANTIATED (decl) = 1;
8391 finish_handler_parms (decl, stmt);
8392 tsubst_expr (HANDLER_BODY (t), args, complain, in_decl);
8393 finish_handler (stmt);
8398 tsubst (TREE_TYPE (t), args, complain, NULL_TREE);
8402 gcc_assert (!STATEMENT_CODE_P (TREE_CODE (t)));
8404 return tsubst_copy_and_build (t, args, complain, in_decl,
8405 /*function_p=*/false);
8411 /* T is a postfix-expression that is not being used in a function
8412 call. Return the substituted version of T. */
8415 tsubst_non_call_postfix_expression (tree t, tree args,
8416 tsubst_flags_t complain,
8419 if (TREE_CODE (t) == SCOPE_REF)
8420 t = tsubst_qualified_id (t, args, complain, in_decl,
8421 /*done=*/false, /*address_p=*/false);
8423 t = tsubst_copy_and_build (t, args, complain, in_decl,
8424 /*function_p=*/false);
8429 /* Like tsubst but deals with expressions and performs semantic
8430 analysis. FUNCTION_P is true if T is the "F" in "F (ARGS)". */
8433 tsubst_copy_and_build (tree t,
8435 tsubst_flags_t complain,
8439 #define RECUR(NODE) \
8440 tsubst_copy_and_build (NODE, args, complain, in_decl, /*function_p=*/false)
8444 if (t == NULL_TREE || t == error_mark_node)
8447 switch (TREE_CODE (t))
8452 case IDENTIFIER_NODE:
8456 bool non_integral_constant_expression_p;
8457 const char *error_msg;
8459 if (IDENTIFIER_TYPENAME_P (t))
8461 tree new_type = tsubst (TREE_TYPE (t), args, complain, in_decl);
8462 t = mangle_conv_op_name_for_type (new_type);
8465 /* Look up the name. */
8466 decl = lookup_name (t, 0);
8468 /* By convention, expressions use ERROR_MARK_NODE to indicate
8469 failure, not NULL_TREE. */
8470 if (decl == NULL_TREE)
8471 decl = error_mark_node;
8473 decl = finish_id_expression (t, decl, NULL_TREE,
8475 /*integral_constant_expression_p=*/false,
8476 /*allow_non_integral_constant_expression_p=*/false,
8477 &non_integral_constant_expression_p,
8478 /*template_p=*/false,
8480 /*address_p=*/false,
8481 /*template_arg_p=*/false,
8485 if (!function_p && TREE_CODE (decl) == IDENTIFIER_NODE)
8486 decl = unqualified_name_lookup_error (decl);
8490 case TEMPLATE_ID_EXPR:
8493 tree template = RECUR (TREE_OPERAND (t, 0));
8494 tree targs = TREE_OPERAND (t, 1);
8497 targs = tsubst_template_args (targs, args, complain, in_decl);
8499 if (TREE_CODE (template) == COMPONENT_REF)
8501 object = TREE_OPERAND (template, 0);
8502 template = TREE_OPERAND (template, 1);
8506 template = lookup_template_function (template, targs);
8509 return build3 (COMPONENT_REF, TREE_TYPE (template),
8510 object, template, NULL_TREE);
8517 tree r = RECUR (TREE_OPERAND (t, 0));
8519 if (REFERENCE_REF_P (t))
8521 /* A type conversion to reference type will be enclosed in
8522 such an indirect ref, but the substitution of the cast
8523 will have also added such an indirect ref. */
8524 if (TREE_CODE (TREE_TYPE (r)) == REFERENCE_TYPE)
8525 r = convert_from_reference (r);
8528 r = build_x_indirect_ref (r, "unary *");
8534 (tsubst (TREE_TYPE (t), args, complain, in_decl),
8535 RECUR (TREE_OPERAND (t, 0)));
8538 return build_functional_cast
8539 (tsubst (TREE_TYPE (t), args, complain, in_decl),
8540 RECUR (TREE_OPERAND (t, 0)));
8542 case REINTERPRET_CAST_EXPR:
8543 return build_reinterpret_cast
8544 (tsubst (TREE_TYPE (t), args, complain, in_decl),
8545 RECUR (TREE_OPERAND (t, 0)));
8547 case CONST_CAST_EXPR:
8548 return build_const_cast
8549 (tsubst (TREE_TYPE (t), args, complain, in_decl),
8550 RECUR (TREE_OPERAND (t, 0)));
8552 case DYNAMIC_CAST_EXPR:
8553 return build_dynamic_cast
8554 (tsubst (TREE_TYPE (t), args, complain, in_decl),
8555 RECUR (TREE_OPERAND (t, 0)));
8557 case STATIC_CAST_EXPR:
8558 return build_static_cast
8559 (tsubst (TREE_TYPE (t), args, complain, in_decl),
8560 RECUR (TREE_OPERAND (t, 0)));
8562 case POSTDECREMENT_EXPR:
8563 case POSTINCREMENT_EXPR:
8564 op1 = tsubst_non_call_postfix_expression (TREE_OPERAND (t, 0),
8565 args, complain, in_decl);
8566 return build_x_unary_op (TREE_CODE (t), op1);
8568 case PREDECREMENT_EXPR:
8569 case PREINCREMENT_EXPR:
8573 case TRUTH_NOT_EXPR:
8574 case UNARY_PLUS_EXPR: /* Unary + */
8577 return build_x_unary_op (TREE_CODE (t), RECUR (TREE_OPERAND (t, 0)));
8580 op1 = TREE_OPERAND (t, 0);
8581 if (TREE_CODE (op1) == SCOPE_REF)
8582 op1 = tsubst_qualified_id (op1, args, complain, in_decl,
8583 /*done=*/true, /*address_p=*/true);
8585 op1 = tsubst_non_call_postfix_expression (op1, args, complain,
8587 if (TREE_CODE (op1) == LABEL_DECL)
8588 return finish_label_address_expr (DECL_NAME (op1));
8589 return build_x_unary_op (ADDR_EXPR, op1);
8594 case TRUNC_DIV_EXPR:
8596 case FLOOR_DIV_EXPR:
8597 case ROUND_DIV_EXPR:
8598 case EXACT_DIV_EXPR:
8602 case TRUNC_MOD_EXPR:
8603 case FLOOR_MOD_EXPR:
8604 case TRUTH_ANDIF_EXPR:
8605 case TRUTH_ORIF_EXPR:
8606 case TRUTH_AND_EXPR:
8622 return build_x_binary_op
8624 RECUR (TREE_OPERAND (t, 0)),
8625 RECUR (TREE_OPERAND (t, 1)),
8626 /*overloaded_p=*/NULL);
8629 return tsubst_qualified_id (t, args, complain, in_decl, /*done=*/true,
8630 /*address_p=*/false);
8632 op1 = tsubst_non_call_postfix_expression (TREE_OPERAND (t, 0),
8633 args, complain, in_decl);
8634 return build_x_binary_op (ARRAY_REF, op1, RECUR (TREE_OPERAND (t, 1)),
8635 /*overloaded_p=*/NULL);
8639 op1 = TREE_OPERAND (t, 0);
8642 /* When there are no ARGS, we are trying to evaluate a
8643 non-dependent expression from the parser. Trying to do
8644 the substitutions may not work. */
8646 op1 = TREE_TYPE (op1);
8655 return cxx_sizeof_or_alignof_type (op1, TREE_CODE (t), true);
8657 return cxx_sizeof_or_alignof_expr (op1, TREE_CODE (t));
8661 tree r = build_x_modify_expr
8662 (RECUR (TREE_OPERAND (t, 0)),
8663 TREE_CODE (TREE_OPERAND (t, 1)),
8664 RECUR (TREE_OPERAND (t, 2)));
8665 /* TREE_NO_WARNING must be set if either the expression was
8666 parenthesized or it uses an operator such as >>= rather
8667 than plain assignment. In the former case, it was already
8668 set and must be copied. In the latter case,
8669 build_x_modify_expr sets it and it must not be reset
8671 if (TREE_NO_WARNING (t))
8672 TREE_NO_WARNING (r) = TREE_NO_WARNING (t);
8677 op1 = tsubst_non_call_postfix_expression (TREE_OPERAND (t, 0),
8678 args, complain, in_decl);
8679 /* Remember that there was a reference to this entity. */
8682 return build_x_arrow (op1);
8686 (RECUR (TREE_OPERAND (t, 0)),
8687 RECUR (TREE_OPERAND (t, 1)),
8688 RECUR (TREE_OPERAND (t, 2)),
8689 RECUR (TREE_OPERAND (t, 3)),
8690 NEW_EXPR_USE_GLOBAL (t));
8693 return delete_sanity
8694 (RECUR (TREE_OPERAND (t, 0)),
8695 RECUR (TREE_OPERAND (t, 1)),
8696 DELETE_EXPR_USE_VEC (t),
8697 DELETE_EXPR_USE_GLOBAL (t));
8700 return build_x_compound_expr (RECUR (TREE_OPERAND (t, 0)),
8701 RECUR (TREE_OPERAND (t, 1)));
8710 function = TREE_OPERAND (t, 0);
8711 /* When we parsed the expression, we determined whether or
8712 not Koenig lookup should be performed. */
8713 koenig_p = KOENIG_LOOKUP_P (t);
8714 if (TREE_CODE (function) == SCOPE_REF)
8717 function = tsubst_qualified_id (function, args, complain, in_decl,
8719 /*address_p=*/false);
8723 if (TREE_CODE (function) == COMPONENT_REF)
8725 tree op = TREE_OPERAND (function, 1);
8727 qualified_p = (TREE_CODE (op) == SCOPE_REF
8729 && BASELINK_QUALIFIED_P (op)));
8732 qualified_p = false;
8734 function = tsubst_copy_and_build (function, args, complain,
8737 if (BASELINK_P (function))
8741 call_args = RECUR (TREE_OPERAND (t, 1));
8743 /* We do not perform argument-dependent lookup if normal
8744 lookup finds a non-function, in accordance with the
8745 expected resolution of DR 218. */
8747 && ((is_overloaded_fn (function)
8748 /* If lookup found a member function, the Koenig lookup is
8749 not appropriate, even if an unqualified-name was used
8750 to denote the function. */
8751 && !DECL_FUNCTION_MEMBER_P (get_first_fn (function)))
8752 || TREE_CODE (function) == IDENTIFIER_NODE))
8753 function = perform_koenig_lookup (function, call_args);
8755 if (TREE_CODE (function) == IDENTIFIER_NODE)
8757 unqualified_name_lookup_error (function);
8758 return error_mark_node;
8761 /* Remember that there was a reference to this entity. */
8762 if (DECL_P (function))
8763 mark_used (function);
8765 if (TREE_CODE (function) == OFFSET_REF)
8766 return build_offset_ref_call_from_tree (function, call_args);
8767 if (TREE_CODE (function) == COMPONENT_REF)
8769 if (!BASELINK_P (TREE_OPERAND (function, 1)))
8770 return finish_call_expr (function, call_args,
8771 /*disallow_virtual=*/false,
8772 /*koenig_p=*/false);
8774 return (build_new_method_call
8775 (TREE_OPERAND (function, 0),
8776 TREE_OPERAND (function, 1),
8777 call_args, NULL_TREE,
8778 qualified_p ? LOOKUP_NONVIRTUAL : LOOKUP_NORMAL));
8780 return finish_call_expr (function, call_args,
8781 /*disallow_virtual=*/qualified_p,
8786 return build_x_conditional_expr
8787 (RECUR (TREE_OPERAND (t, 0)),
8788 RECUR (TREE_OPERAND (t, 1)),
8789 RECUR (TREE_OPERAND (t, 2)));
8791 case PSEUDO_DTOR_EXPR:
8792 return finish_pseudo_destructor_expr
8793 (RECUR (TREE_OPERAND (t, 0)),
8794 RECUR (TREE_OPERAND (t, 1)),
8795 RECUR (TREE_OPERAND (t, 2)));
8799 tree purpose, value, chain;
8801 if (t == void_list_node)
8804 purpose = TREE_PURPOSE (t);
8806 purpose = RECUR (purpose);
8807 value = TREE_VALUE (t);
8809 value = RECUR (value);
8810 chain = TREE_CHAIN (t);
8811 if (chain && chain != void_type_node)
8812 chain = RECUR (chain);
8813 if (purpose == TREE_PURPOSE (t)
8814 && value == TREE_VALUE (t)
8815 && chain == TREE_CHAIN (t))
8817 return tree_cons (purpose, value, chain);
8825 object = tsubst_non_call_postfix_expression (TREE_OPERAND (t, 0),
8826 args, complain, in_decl);
8827 /* Remember that there was a reference to this entity. */
8828 if (DECL_P (object))
8831 member = TREE_OPERAND (t, 1);
8832 if (BASELINK_P (member))
8833 member = tsubst_baselink (member,
8834 non_reference (TREE_TYPE (object)),
8835 args, complain, in_decl);
8837 member = tsubst_copy (member, args, complain, in_decl);
8839 if (member == error_mark_node)
8840 return error_mark_node;
8841 else if (!CLASS_TYPE_P (TREE_TYPE (object)))
8843 if (TREE_CODE (member) == BIT_NOT_EXPR)
8844 return finish_pseudo_destructor_expr (object,
8846 TREE_TYPE (object));
8847 else if (TREE_CODE (member) == SCOPE_REF
8848 && (TREE_CODE (TREE_OPERAND (member, 1)) == BIT_NOT_EXPR))
8849 return finish_pseudo_destructor_expr (object,
8851 TREE_TYPE (object));
8853 else if (TREE_CODE (member) == SCOPE_REF
8854 && TREE_CODE (TREE_OPERAND (member, 1)) == TEMPLATE_ID_EXPR)
8859 /* Lookup the template functions now that we know what the
8861 tmpl = TREE_OPERAND (TREE_OPERAND (member, 1), 0);
8862 args = TREE_OPERAND (TREE_OPERAND (member, 1), 1);
8863 member = lookup_qualified_name (TREE_OPERAND (member, 0), tmpl,
8864 /*is_type_p=*/false,
8865 /*complain=*/false);
8866 if (BASELINK_P (member))
8868 BASELINK_FUNCTIONS (member)
8869 = build_nt (TEMPLATE_ID_EXPR, BASELINK_FUNCTIONS (member),
8871 member = (adjust_result_of_qualified_name_lookup
8872 (member, BINFO_TYPE (BASELINK_BINFO (member)),
8873 TREE_TYPE (object)));
8877 qualified_name_lookup_error (TREE_TYPE (object), tmpl,
8879 return error_mark_node;
8882 else if (TREE_CODE (member) == SCOPE_REF
8883 && !CLASS_TYPE_P (TREE_OPERAND (member, 0))
8884 && TREE_CODE (TREE_OPERAND (member, 0)) != NAMESPACE_DECL)
8886 if (complain & tf_error)
8888 if (TYPE_P (TREE_OPERAND (member, 0)))
8889 error ("%qT is not a class or namespace",
8890 TREE_OPERAND (member, 0));
8892 error ("%qD is not a class or namespace",
8893 TREE_OPERAND (member, 0));
8895 return error_mark_node;
8897 else if (TREE_CODE (member) == FIELD_DECL)
8898 return finish_non_static_data_member (member, object, NULL_TREE);
8900 return finish_class_member_access_expr (object, member,
8901 /*template_p=*/false);
8906 (RECUR (TREE_OPERAND (t, 0)));
8910 VEC(constructor_elt,gc) *n;
8911 constructor_elt *ce;
8912 unsigned HOST_WIDE_INT idx;
8914 tree type = tsubst (TREE_TYPE (t), args, complain, in_decl);
8915 bool process_index_p;
8917 /* digest_init will do the wrong thing if we let it. */
8918 if (type && TYPE_PTRMEMFUNC_P (type))
8921 /* We do not want to process the index of aggregate
8922 initializers as they are identifier nodes which will be
8923 looked up by digest_init. */
8924 process_index_p = !(type && IS_AGGR_TYPE (type));
8926 n = VEC_copy (constructor_elt, gc, CONSTRUCTOR_ELTS (t));
8927 for (idx = 0; VEC_iterate (constructor_elt, n, idx, ce); idx++)
8929 if (ce->index && process_index_p)
8930 ce->index = RECUR (ce->index);
8931 ce->value = RECUR (ce->value);
8934 r = build_constructor (NULL_TREE, n);
8935 TREE_HAS_CONSTRUCTOR (r) = TREE_HAS_CONSTRUCTOR (t);
8938 return digest_init (type, r);
8944 tree operand_0 = RECUR (TREE_OPERAND (t, 0));
8945 if (TYPE_P (operand_0))
8946 return get_typeid (operand_0);
8947 return build_typeid (operand_0);
8957 tree r = tsubst_copy (t, args, complain, in_decl);
8959 if (TREE_CODE (TREE_TYPE (t)) != REFERENCE_TYPE)
8960 /* If the original type was a reference, we'll be wrapped in
8961 the appropriate INDIRECT_REF. */
8962 r = convert_from_reference (r);
8967 return build_x_va_arg (RECUR (TREE_OPERAND (t, 0)),
8968 tsubst_copy (TREE_TYPE (t), args, complain,
8972 return fold_offsetof (RECUR (TREE_OPERAND (t, 0)));
8976 tree old_stmt_expr = cur_stmt_expr;
8977 tree stmt_expr = begin_stmt_expr ();
8979 cur_stmt_expr = stmt_expr;
8980 tsubst_expr (STMT_EXPR_STMT (t), args, complain, in_decl);
8981 stmt_expr = finish_stmt_expr (stmt_expr, false);
8982 cur_stmt_expr = old_stmt_expr;
8988 t = tsubst_copy (t, args, complain, in_decl);
8989 /* As in finish_id_expression, we resolve enumeration constants
8990 to their underlying values. */
8991 if (TREE_CODE (t) == CONST_DECL)
8992 return DECL_INITIAL (t);
8996 /* Handle Objective-C++ constructs, if appropriate. */
8999 = objcp_tsubst_copy_and_build (t, args, complain,
9000 in_decl, /*function_p=*/false);
9004 return tsubst_copy (t, args, complain, in_decl);
9010 /* Verify that the instantiated ARGS are valid. For type arguments,
9011 make sure that the type's linkage is ok. For non-type arguments,
9012 make sure they are constants if they are integral or enumerations.
9013 Emit an error under control of COMPLAIN, and return TRUE on error. */
9016 check_instantiated_args (tree tmpl, tree args, tsubst_flags_t complain)
9018 int ix, len = DECL_NTPARMS (tmpl);
9019 bool result = false;
9021 for (ix = 0; ix != len; ix++)
9023 tree t = TREE_VEC_ELT (args, ix);
9027 /* [basic.link]: A name with no linkage (notably, the name
9028 of a class or enumeration declared in a local scope)
9029 shall not be used to declare an entity with linkage.
9030 This implies that names with no linkage cannot be used as
9031 template arguments. */
9032 tree nt = no_linkage_check (t, /*relaxed_p=*/false);
9036 /* DR 488 makes use of a type with no linkage cause
9037 type deduction to fail. */
9038 if (complain & tf_error)
9040 if (TYPE_ANONYMOUS_P (nt))
9041 error ("%qT is/uses anonymous type", t);
9043 error ("%qT uses local type %qT", t, nt);
9047 /* In order to avoid all sorts of complications, we do not
9048 allow variably-modified types as template arguments. */
9049 else if (variably_modified_type_p (t, NULL_TREE))
9051 if (complain & tf_error)
9052 error ("%qT is a variably modified type", t);
9056 /* A non-type argument of integral or enumerated type must be a
9058 else if (TREE_TYPE (t)
9059 && INTEGRAL_OR_ENUMERATION_TYPE_P (TREE_TYPE (t))
9060 && !TREE_CONSTANT (t))
9062 if (complain & tf_error)
9063 error ("integral expression %qE is not constant", t);
9067 if (result && (complain & tf_error))
9068 error (" trying to instantiate %qD", tmpl);
9072 /* Instantiate the indicated variable or function template TMPL with
9073 the template arguments in TARG_PTR. */
9076 instantiate_template (tree tmpl, tree targ_ptr, tsubst_flags_t complain)
9082 if (tmpl == error_mark_node)
9083 return error_mark_node;
9085 gcc_assert (TREE_CODE (tmpl) == TEMPLATE_DECL);
9087 /* If this function is a clone, handle it specially. */
9088 if (DECL_CLONED_FUNCTION_P (tmpl))
9093 spec = instantiate_template (DECL_CLONED_FUNCTION (tmpl), targ_ptr,
9095 if (spec == error_mark_node)
9096 return error_mark_node;
9098 /* Look for the clone. */
9099 FOR_EACH_CLONE (clone, spec)
9100 if (DECL_NAME (clone) == DECL_NAME (tmpl))
9102 /* We should always have found the clone by now. */
9107 /* Check to see if we already have this specialization. */
9108 spec = retrieve_specialization (tmpl, targ_ptr,
9109 /*class_specializations_p=*/false);
9110 if (spec != NULL_TREE)
9113 gen_tmpl = most_general_template (tmpl);
9114 if (tmpl != gen_tmpl)
9116 /* The TMPL is a partial instantiation. To get a full set of
9117 arguments we must add the arguments used to perform the
9118 partial instantiation. */
9119 targ_ptr = add_outermost_template_args (DECL_TI_ARGS (tmpl),
9122 /* Check to see if we already have this specialization. */
9123 spec = retrieve_specialization (gen_tmpl, targ_ptr,
9124 /*class_specializations_p=*/false);
9125 if (spec != NULL_TREE)
9129 if (check_instantiated_args (gen_tmpl, INNERMOST_TEMPLATE_ARGS (targ_ptr),
9131 return error_mark_node;
9133 /* We are building a FUNCTION_DECL, during which the access of its
9134 parameters and return types have to be checked. However this
9135 FUNCTION_DECL which is the desired context for access checking
9136 is not built yet. We solve this chicken-and-egg problem by
9137 deferring all checks until we have the FUNCTION_DECL. */
9138 push_deferring_access_checks (dk_deferred);
9140 /* Substitute template parameters. */
9141 fndecl = tsubst (DECL_TEMPLATE_RESULT (gen_tmpl),
9142 targ_ptr, complain, gen_tmpl);
9144 /* Now we know the specialization, compute access previously
9146 push_access_scope (fndecl);
9147 perform_deferred_access_checks ();
9148 pop_access_scope (fndecl);
9149 pop_deferring_access_checks ();
9151 /* The DECL_TI_TEMPLATE should always be the immediate parent
9152 template, not the most general template. */
9153 DECL_TI_TEMPLATE (fndecl) = tmpl;
9155 /* If we've just instantiated the main entry point for a function,
9156 instantiate all the alternate entry points as well. We do this
9157 by cloning the instantiation of the main entry point, not by
9158 instantiating the template clones. */
9159 if (TREE_CHAIN (gen_tmpl) && DECL_CLONED_FUNCTION_P (TREE_CHAIN (gen_tmpl)))
9160 clone_function_decl (fndecl, /*update_method_vec_p=*/0);
9165 /* The FN is a TEMPLATE_DECL for a function. The ARGS are the
9166 arguments that are being used when calling it. TARGS is a vector
9167 into which the deduced template arguments are placed.
9169 Return zero for success, 2 for an incomplete match that doesn't resolve
9170 all the types, and 1 for complete failure. An error message will be
9171 printed only for an incomplete match.
9173 If FN is a conversion operator, or we are trying to produce a specific
9174 specialization, RETURN_TYPE is the return type desired.
9176 The EXPLICIT_TARGS are explicit template arguments provided via a
9179 The parameter STRICT is one of:
9182 We are deducing arguments for a function call, as in
9186 We are deducing arguments for a conversion function, as in
9190 We are deducing arguments when doing an explicit instantiation
9191 as in [temp.explicit], when determining an explicit specialization
9192 as in [temp.expl.spec], or when taking the address of a function
9193 template, as in [temp.deduct.funcaddr]. */
9196 fn_type_unification (tree fn,
9197 tree explicit_targs,
9201 unification_kind_t strict,
9208 gcc_assert (TREE_CODE (fn) == TEMPLATE_DECL);
9210 fntype = TREE_TYPE (fn);
9215 The specified template arguments must match the template
9216 parameters in kind (i.e., type, nontype, template), and there
9217 must not be more arguments than there are parameters;
9218 otherwise type deduction fails.
9220 Nontype arguments must match the types of the corresponding
9221 nontype template parameters, or must be convertible to the
9222 types of the corresponding nontype parameters as specified in
9223 _temp.arg.nontype_, otherwise type deduction fails.
9225 All references in the function type of the function template
9226 to the corresponding template parameters are replaced by the
9227 specified template argument values. If a substitution in a
9228 template parameter or in the function type of the function
9229 template results in an invalid type, type deduction fails. */
9231 tree converted_args;
9234 if (explicit_targs == error_mark_node)
9238 = (coerce_template_parms (DECL_INNERMOST_TEMPLATE_PARMS (fn),
9239 explicit_targs, NULL_TREE, tf_none,
9240 /*require_all_arguments=*/0));
9241 if (converted_args == error_mark_node)
9244 /* Substitute the explicit args into the function type. This is
9245 necessary so that, for instance, explicitly declared function
9246 arguments can match null pointed constants. If we were given
9247 an incomplete set of explicit args, we must not do semantic
9248 processing during substitution as we could create partial
9250 incomplete = NUM_TMPL_ARGS (explicit_targs) != NUM_TMPL_ARGS (targs);
9251 processing_template_decl += incomplete;
9252 fntype = tsubst (fntype, converted_args, tf_none, NULL_TREE);
9253 processing_template_decl -= incomplete;
9255 if (fntype == error_mark_node)
9258 /* Place the explicitly specified arguments in TARGS. */
9259 for (i = NUM_TMPL_ARGS (converted_args); i--;)
9260 TREE_VEC_ELT (targs, i) = TREE_VEC_ELT (converted_args, i);
9263 parms = TYPE_ARG_TYPES (fntype);
9264 /* Never do unification on the 'this' parameter. */
9265 if (DECL_NONSTATIC_MEMBER_FUNCTION_P (fn))
9266 parms = TREE_CHAIN (parms);
9270 parms = tree_cons (NULL_TREE, TREE_TYPE (fntype), parms);
9271 args = tree_cons (NULL_TREE, return_type, args);
9274 /* We allow incomplete unification without an error message here
9275 because the standard doesn't seem to explicitly prohibit it. Our
9276 callers must be ready to deal with unification failures in any
9278 result = type_unification_real (DECL_INNERMOST_TEMPLATE_PARMS (fn),
9279 targs, parms, args, /*subr=*/0,
9283 /* All is well so far. Now, check:
9287 When all template arguments have been deduced, all uses of
9288 template parameters in nondeduced contexts are replaced with
9289 the corresponding deduced argument values. If the
9290 substitution results in an invalid type, as described above,
9291 type deduction fails. */
9292 if (tsubst (TREE_TYPE (fn), targs, tf_none, NULL_TREE)
9299 /* Adjust types before performing type deduction, as described in
9300 [temp.deduct.call] and [temp.deduct.conv]. The rules in these two
9301 sections are symmetric. PARM is the type of a function parameter
9302 or the return type of the conversion function. ARG is the type of
9303 the argument passed to the call, or the type of the value
9304 initialized with the result of the conversion function. */
9307 maybe_adjust_types_for_deduction (unification_kind_t strict,
9320 /* Swap PARM and ARG throughout the remainder of this
9321 function; the handling is precisely symmetric since PARM
9322 will initialize ARG rather than vice versa. */
9330 /* There is nothing to do in this case. */
9337 if (TREE_CODE (*parm) != REFERENCE_TYPE)
9339 /* [temp.deduct.call]
9341 If P is not a reference type:
9343 --If A is an array type, the pointer type produced by the
9344 array-to-pointer standard conversion (_conv.array_) is
9345 used in place of A for type deduction; otherwise,
9347 --If A is a function type, the pointer type produced by
9348 the function-to-pointer standard conversion
9349 (_conv.func_) is used in place of A for type deduction;
9352 --If A is a cv-qualified type, the top level
9353 cv-qualifiers of A's type are ignored for type
9355 if (TREE_CODE (*arg) == ARRAY_TYPE)
9356 *arg = build_pointer_type (TREE_TYPE (*arg));
9357 else if (TREE_CODE (*arg) == FUNCTION_TYPE)
9358 *arg = build_pointer_type (*arg);
9360 *arg = TYPE_MAIN_VARIANT (*arg);
9363 /* [temp.deduct.call]
9365 If P is a cv-qualified type, the top level cv-qualifiers
9366 of P's type are ignored for type deduction. If P is a
9367 reference type, the type referred to by P is used for
9369 *parm = TYPE_MAIN_VARIANT (*parm);
9370 if (TREE_CODE (*parm) == REFERENCE_TYPE)
9372 *parm = TREE_TYPE (*parm);
9373 result |= UNIFY_ALLOW_OUTER_MORE_CV_QUAL;
9376 /* DR 322. For conversion deduction, remove a reference type on parm
9377 too (which has been swapped into ARG). */
9378 if (strict == DEDUCE_CONV && TREE_CODE (*arg) == REFERENCE_TYPE)
9379 *arg = TREE_TYPE (*arg);
9384 /* Most parms like fn_type_unification.
9386 If SUBR is 1, we're being called recursively (to unify the
9387 arguments of a function or method parameter of a function
9391 type_unification_real (tree tparms,
9396 unification_kind_t strict,
9401 int ntparms = TREE_VEC_LENGTH (tparms);
9403 int saw_undeduced = 0;
9406 gcc_assert (TREE_CODE (tparms) == TREE_VEC);
9407 gcc_assert (xparms == NULL_TREE || TREE_CODE (xparms) == TREE_LIST);
9408 gcc_assert (!xargs || TREE_CODE (xargs) == TREE_LIST);
9409 gcc_assert (ntparms > 0);
9414 sub_strict = (UNIFY_ALLOW_OUTER_LEVEL | UNIFY_ALLOW_MORE_CV_QUAL
9415 | UNIFY_ALLOW_DERIVED);
9419 sub_strict = UNIFY_ALLOW_LESS_CV_QUAL;
9423 sub_strict = UNIFY_ALLOW_NONE;
9434 while (parms && parms != void_list_node
9435 && args && args != void_list_node)
9437 parm = TREE_VALUE (parms);
9438 parms = TREE_CHAIN (parms);
9439 arg = TREE_VALUE (args);
9440 args = TREE_CHAIN (args);
9442 if (arg == error_mark_node)
9444 if (arg == unknown_type_node)
9445 /* We can't deduce anything from this, but we might get all the
9446 template args from other function args. */
9449 /* Conversions will be performed on a function argument that
9450 corresponds with a function parameter that contains only
9451 non-deducible template parameters and explicitly specified
9452 template parameters. */
9453 if (!uses_template_parms (parm))
9458 type = TREE_TYPE (arg);
9462 if (same_type_p (parm, type))
9464 if (strict != DEDUCE_EXACT
9465 && can_convert_arg (parm, type, TYPE_P (arg) ? NULL_TREE : arg,
9474 gcc_assert (TREE_TYPE (arg) != NULL_TREE);
9475 if (type_unknown_p (arg))
9477 /* [temp.deduct.type] A template-argument can be deduced from
9478 a pointer to function or pointer to member function
9479 argument if the set of overloaded functions does not
9480 contain function templates and at most one of a set of
9481 overloaded functions provides a unique match. */
9483 if (resolve_overloaded_unification
9484 (tparms, targs, parm, arg, strict, sub_strict)
9489 arg = TREE_TYPE (arg);
9490 if (arg == error_mark_node)
9495 int arg_strict = sub_strict;
9498 arg_strict |= maybe_adjust_types_for_deduction (strict, &parm, &arg);
9500 if (unify (tparms, targs, parm, arg, arg_strict))
9505 /* Fail if we've reached the end of the parm list, and more args
9506 are present, and the parm list isn't variadic. */
9507 if (args && args != void_list_node && parms == void_list_node)
9509 /* Fail if parms are left and they don't have default values. */
9510 if (parms && parms != void_list_node
9511 && TREE_PURPOSE (parms) == NULL_TREE)
9515 for (i = 0; i < ntparms; i++)
9516 if (!TREE_VEC_ELT (targs, i))
9518 tree tparm = TREE_VALUE (TREE_VEC_ELT (tparms, i));
9520 /* If this is an undeduced nontype parameter that depends on
9521 a type parameter, try another pass; its type may have been
9522 deduced from a later argument than the one from which
9523 this parameter can be deduced. */
9524 if (TREE_CODE (tparm) == PARM_DECL
9525 && uses_template_parms (TREE_TYPE (tparm))
9526 && !saw_undeduced++)
9535 /* Subroutine of type_unification_real. Args are like the variables at the
9536 call site. ARG is an overloaded function (or template-id); we try
9537 deducing template args from each of the overloads, and if only one
9538 succeeds, we go with that. Modifies TARGS and returns 0 on success. */
9541 resolve_overloaded_unification (tree tparms,
9545 unification_kind_t strict,
9548 tree tempargs = copy_node (targs);
9552 if (TREE_CODE (arg) == ADDR_EXPR)
9554 arg = TREE_OPERAND (arg, 0);
9560 if (TREE_CODE (arg) == COMPONENT_REF)
9561 /* Handle `&x' where `x' is some static or non-static member
9563 arg = TREE_OPERAND (arg, 1);
9565 if (TREE_CODE (arg) == OFFSET_REF)
9566 arg = TREE_OPERAND (arg, 1);
9568 /* Strip baselink information. */
9569 if (BASELINK_P (arg))
9570 arg = BASELINK_FUNCTIONS (arg);
9572 if (TREE_CODE (arg) == TEMPLATE_ID_EXPR)
9574 /* If we got some explicit template args, we need to plug them into
9575 the affected templates before we try to unify, in case the
9576 explicit args will completely resolve the templates in question. */
9578 tree expl_subargs = TREE_OPERAND (arg, 1);
9579 arg = TREE_OPERAND (arg, 0);
9581 for (; arg; arg = OVL_NEXT (arg))
9583 tree fn = OVL_CURRENT (arg);
9586 if (TREE_CODE (fn) != TEMPLATE_DECL)
9589 subargs = get_bindings (fn, DECL_TEMPLATE_RESULT (fn),
9590 expl_subargs, /*check_ret=*/false);
9593 elem = tsubst (TREE_TYPE (fn), subargs, tf_none, NULL_TREE);
9594 good += try_one_overload (tparms, targs, tempargs, parm,
9595 elem, strict, sub_strict, addr_p);
9601 gcc_assert (TREE_CODE (arg) == OVERLOAD
9602 || TREE_CODE (arg) == FUNCTION_DECL);
9604 for (; arg; arg = OVL_NEXT (arg))
9605 good += try_one_overload (tparms, targs, tempargs, parm,
9606 TREE_TYPE (OVL_CURRENT (arg)),
9607 strict, sub_strict, addr_p);
9610 /* [temp.deduct.type] A template-argument can be deduced from a pointer
9611 to function or pointer to member function argument if the set of
9612 overloaded functions does not contain function templates and at most
9613 one of a set of overloaded functions provides a unique match.
9615 So if we found multiple possibilities, we return success but don't
9620 int i = TREE_VEC_LENGTH (targs);
9622 if (TREE_VEC_ELT (tempargs, i))
9623 TREE_VEC_ELT (targs, i) = TREE_VEC_ELT (tempargs, i);
9631 /* Subroutine of resolve_overloaded_unification; does deduction for a single
9632 overload. Fills TARGS with any deduced arguments, or error_mark_node if
9633 different overloads deduce different arguments for a given parm.
9634 ADDR_P is true if the expression for which deduction is being
9635 performed was of the form "& fn" rather than simply "fn".
9637 Returns 1 on success. */
9640 try_one_overload (tree tparms,
9645 unification_kind_t strict,
9653 /* [temp.deduct.type] A template-argument can be deduced from a pointer
9654 to function or pointer to member function argument if the set of
9655 overloaded functions does not contain function templates and at most
9656 one of a set of overloaded functions provides a unique match.
9658 So if this is a template, just return success. */
9660 if (uses_template_parms (arg))
9663 if (TREE_CODE (arg) == METHOD_TYPE)
9664 arg = build_ptrmemfunc_type (build_pointer_type (arg));
9666 arg = build_pointer_type (arg);
9668 sub_strict |= maybe_adjust_types_for_deduction (strict, &parm, &arg);
9670 /* We don't copy orig_targs for this because if we have already deduced
9671 some template args from previous args, unify would complain when we
9672 try to deduce a template parameter for the same argument, even though
9673 there isn't really a conflict. */
9674 nargs = TREE_VEC_LENGTH (targs);
9675 tempargs = make_tree_vec (nargs);
9677 if (unify (tparms, tempargs, parm, arg, sub_strict) != 0)
9680 /* First make sure we didn't deduce anything that conflicts with
9681 explicitly specified args. */
9682 for (i = nargs; i--; )
9684 tree elt = TREE_VEC_ELT (tempargs, i);
9685 tree oldelt = TREE_VEC_ELT (orig_targs, i);
9689 else if (uses_template_parms (elt))
9690 /* Since we're unifying against ourselves, we will fill in
9691 template args used in the function parm list with our own
9692 template parms. Discard them. */
9693 TREE_VEC_ELT (tempargs, i) = NULL_TREE;
9694 else if (oldelt && !template_args_equal (oldelt, elt))
9698 for (i = nargs; i--; )
9700 tree elt = TREE_VEC_ELT (tempargs, i);
9703 TREE_VEC_ELT (targs, i) = elt;
9709 /* Verify that nondeduce template argument agrees with the type
9710 obtained from argument deduction. Return nonzero if the
9715 struct A { typedef int X; };
9716 template <class T, class U> struct C {};
9717 template <class T> struct C<T, typename T::X> {};
9719 Then with the instantiation `C<A, int>', we can deduce that
9720 `T' is `A' but unify () does not check whether `typename T::X'
9721 is `int'. This function ensure that they agree.
9723 TARGS, PARMS are the same as the arguments of unify.
9724 ARGS contains template arguments from all levels. */
9727 verify_class_unification (tree targs, tree parms, tree args)
9729 parms = tsubst (parms, add_outermost_template_args (args, targs),
9730 tf_none, NULL_TREE);
9731 if (parms == error_mark_node)
9734 return !comp_template_args (parms, INNERMOST_TEMPLATE_ARGS (args));
9737 /* PARM is a template class (perhaps with unbound template
9738 parameters). ARG is a fully instantiated type. If ARG can be
9739 bound to PARM, return ARG, otherwise return NULL_TREE. TPARMS and
9740 TARGS are as for unify. */
9743 try_class_unification (tree tparms, tree targs, tree parm, tree arg)
9747 if (!CLASSTYPE_TEMPLATE_INFO (arg)
9748 || (most_general_template (CLASSTYPE_TI_TEMPLATE (arg))
9749 != most_general_template (CLASSTYPE_TI_TEMPLATE (parm))))
9752 /* We need to make a new template argument vector for the call to
9753 unify. If we used TARGS, we'd clutter it up with the result of
9754 the attempted unification, even if this class didn't work out.
9755 We also don't want to commit ourselves to all the unifications
9756 we've already done, since unification is supposed to be done on
9757 an argument-by-argument basis. In other words, consider the
9758 following pathological case:
9760 template <int I, int J, int K>
9763 template <int I, int J>
9764 struct S<I, J, 2> : public S<I, I, I>, S<J, J, J> {};
9766 template <int I, int J, int K>
9767 void f(S<I, J, K>, S<I, I, I>);
9776 Now, by the time we consider the unification involving `s2', we
9777 already know that we must have `f<0, 0, 0>'. But, even though
9778 `S<0, 1, 2>' is derived from `S<0, 0, 0>', the code is invalid
9779 because there are two ways to unify base classes of S<0, 1, 2>
9780 with S<I, I, I>. If we kept the already deduced knowledge, we
9781 would reject the possibility I=1. */
9782 copy_of_targs = make_tree_vec (TREE_VEC_LENGTH (targs));
9784 /* If unification failed, we're done. */
9785 if (unify (tparms, copy_of_targs, CLASSTYPE_TI_ARGS (parm),
9786 CLASSTYPE_TI_ARGS (arg), UNIFY_ALLOW_NONE))
9792 /* Given a template type PARM and a class type ARG, find the unique
9793 base type in ARG that is an instance of PARM. We do not examine
9794 ARG itself; only its base-classes. If there is not exactly one
9795 appropriate base class, return NULL_TREE. PARM may be the type of
9796 a partial specialization, as well as a plain template type. Used
9800 get_template_base (tree tparms, tree targs, tree parm, tree arg)
9802 tree rval = NULL_TREE;
9805 gcc_assert (IS_AGGR_TYPE_CODE (TREE_CODE (arg)));
9807 binfo = TYPE_BINFO (complete_type (arg));
9809 /* The type could not be completed. */
9812 /* Walk in inheritance graph order. The search order is not
9813 important, and this avoids multiple walks of virtual bases. */
9814 for (binfo = TREE_CHAIN (binfo); binfo; binfo = TREE_CHAIN (binfo))
9816 tree r = try_class_unification (tparms, targs, parm, BINFO_TYPE (binfo));
9820 /* If there is more than one satisfactory baseclass, then:
9824 If they yield more than one possible deduced A, the type
9828 if (rval && !same_type_p (r, rval))
9838 /* Returns the level of DECL, which declares a template parameter. */
9841 template_decl_level (tree decl)
9843 switch (TREE_CODE (decl))
9847 return TEMPLATE_TYPE_LEVEL (TREE_TYPE (decl));
9850 return TEMPLATE_PARM_LEVEL (DECL_INITIAL (decl));
9858 /* Decide whether ARG can be unified with PARM, considering only the
9859 cv-qualifiers of each type, given STRICT as documented for unify.
9860 Returns nonzero iff the unification is OK on that basis. */
9863 check_cv_quals_for_unify (int strict, tree arg, tree parm)
9865 int arg_quals = cp_type_quals (arg);
9866 int parm_quals = cp_type_quals (parm);
9868 if (TREE_CODE (parm) == TEMPLATE_TYPE_PARM
9869 && !(strict & UNIFY_ALLOW_OUTER_MORE_CV_QUAL))
9871 /* Although a CVR qualifier is ignored when being applied to a
9872 substituted template parameter ([8.3.2]/1 for example), that
9873 does not apply during deduction [14.8.2.4]/1, (even though
9874 that is not explicitly mentioned, [14.8.2.4]/9 indicates
9875 this). Except when we're allowing additional CV qualifiers
9876 at the outer level [14.8.2.1]/3,1st bullet. */
9877 if ((TREE_CODE (arg) == REFERENCE_TYPE
9878 || TREE_CODE (arg) == FUNCTION_TYPE
9879 || TREE_CODE (arg) == METHOD_TYPE)
9880 && (parm_quals & (TYPE_QUAL_CONST | TYPE_QUAL_VOLATILE)))
9883 if ((!POINTER_TYPE_P (arg) && TREE_CODE (arg) != TEMPLATE_TYPE_PARM)
9884 && (parm_quals & TYPE_QUAL_RESTRICT))
9888 if (!(strict & (UNIFY_ALLOW_MORE_CV_QUAL | UNIFY_ALLOW_OUTER_MORE_CV_QUAL))
9889 && (arg_quals & parm_quals) != parm_quals)
9892 if (!(strict & (UNIFY_ALLOW_LESS_CV_QUAL | UNIFY_ALLOW_OUTER_LESS_CV_QUAL))
9893 && (parm_quals & arg_quals) != arg_quals)
9899 /* Takes parameters as for type_unification. Returns 0 if the
9900 type deduction succeeds, 1 otherwise. The parameter STRICT is a
9901 bitwise or of the following flags:
9904 Require an exact match between PARM and ARG.
9905 UNIFY_ALLOW_MORE_CV_QUAL:
9906 Allow the deduced ARG to be more cv-qualified (by qualification
9907 conversion) than ARG.
9908 UNIFY_ALLOW_LESS_CV_QUAL:
9909 Allow the deduced ARG to be less cv-qualified than ARG.
9910 UNIFY_ALLOW_DERIVED:
9911 Allow the deduced ARG to be a template base class of ARG,
9912 or a pointer to a template base class of the type pointed to by
9914 UNIFY_ALLOW_INTEGER:
9915 Allow any integral type to be deduced. See the TEMPLATE_PARM_INDEX
9916 case for more information.
9917 UNIFY_ALLOW_OUTER_LEVEL:
9918 This is the outermost level of a deduction. Used to determine validity
9919 of qualification conversions. A valid qualification conversion must
9920 have const qualified pointers leading up to the inner type which
9921 requires additional CV quals, except at the outer level, where const
9922 is not required [conv.qual]. It would be normal to set this flag in
9923 addition to setting UNIFY_ALLOW_MORE_CV_QUAL.
9924 UNIFY_ALLOW_OUTER_MORE_CV_QUAL:
9925 This is the outermost level of a deduction, and PARM can be more CV
9926 qualified at this point.
9927 UNIFY_ALLOW_OUTER_LESS_CV_QUAL:
9928 This is the outermost level of a deduction, and PARM can be less CV
9929 qualified at this point. */
9932 unify (tree tparms, tree targs, tree parm, tree arg, int strict)
9937 int strict_in = strict;
9939 /* I don't think this will do the right thing with respect to types.
9940 But the only case I've seen it in so far has been array bounds, where
9941 signedness is the only information lost, and I think that will be
9943 while (TREE_CODE (parm) == NOP_EXPR)
9944 parm = TREE_OPERAND (parm, 0);
9946 if (arg == error_mark_node)
9948 if (arg == unknown_type_node)
9949 /* We can't deduce anything from this, but we might get all the
9950 template args from other function args. */
9953 /* If PARM uses template parameters, then we can't bail out here,
9954 even if ARG == PARM, since we won't record unifications for the
9955 template parameters. We might need them if we're trying to
9956 figure out which of two things is more specialized. */
9957 if (arg == parm && !uses_template_parms (parm))
9960 /* Immediately reject some pairs that won't unify because of
9961 cv-qualification mismatches. */
9962 if (TREE_CODE (arg) == TREE_CODE (parm)
9964 /* It is the elements of the array which hold the cv quals of an array
9965 type, and the elements might be template type parms. We'll check
9967 && TREE_CODE (arg) != ARRAY_TYPE
9968 /* We check the cv-qualifiers when unifying with template type
9969 parameters below. We want to allow ARG `const T' to unify with
9970 PARM `T' for example, when computing which of two templates
9971 is more specialized, for example. */
9972 && TREE_CODE (arg) != TEMPLATE_TYPE_PARM
9973 && !check_cv_quals_for_unify (strict_in, arg, parm))
9976 if (!(strict & UNIFY_ALLOW_OUTER_LEVEL)
9977 && TYPE_P (parm) && !CP_TYPE_CONST_P (parm))
9978 strict &= ~UNIFY_ALLOW_MORE_CV_QUAL;
9979 strict &= ~UNIFY_ALLOW_OUTER_LEVEL;
9980 strict &= ~UNIFY_ALLOW_DERIVED;
9981 strict &= ~UNIFY_ALLOW_OUTER_MORE_CV_QUAL;
9982 strict &= ~UNIFY_ALLOW_OUTER_LESS_CV_QUAL;
9984 switch (TREE_CODE (parm))
9988 case UNBOUND_CLASS_TEMPLATE:
9989 /* In a type which contains a nested-name-specifier, template
9990 argument values cannot be deduced for template parameters used
9991 within the nested-name-specifier. */
9994 case TEMPLATE_TYPE_PARM:
9995 case TEMPLATE_TEMPLATE_PARM:
9996 case BOUND_TEMPLATE_TEMPLATE_PARM:
9997 tparm = TREE_VALUE (TREE_VEC_ELT (tparms, 0));
9999 if (TEMPLATE_TYPE_LEVEL (parm)
10000 != template_decl_level (tparm))
10001 /* The PARM is not one we're trying to unify. Just check
10002 to see if it matches ARG. */
10003 return (TREE_CODE (arg) == TREE_CODE (parm)
10004 && same_type_p (parm, arg)) ? 0 : 1;
10005 idx = TEMPLATE_TYPE_IDX (parm);
10006 targ = TREE_VEC_ELT (targs, idx);
10007 tparm = TREE_VALUE (TREE_VEC_ELT (tparms, idx));
10009 /* Check for mixed types and values. */
10010 if ((TREE_CODE (parm) == TEMPLATE_TYPE_PARM
10011 && TREE_CODE (tparm) != TYPE_DECL)
10012 || (TREE_CODE (parm) == TEMPLATE_TEMPLATE_PARM
10013 && TREE_CODE (tparm) != TEMPLATE_DECL))
10016 if (TREE_CODE (parm) == BOUND_TEMPLATE_TEMPLATE_PARM)
10018 /* ARG must be constructed from a template class or a template
10019 template parameter. */
10020 if (TREE_CODE (arg) != BOUND_TEMPLATE_TEMPLATE_PARM
10021 && (TREE_CODE (arg) != RECORD_TYPE || !CLASSTYPE_TEMPLATE_INFO (arg)))
10025 tree parmtmpl = TYPE_TI_TEMPLATE (parm);
10026 tree parmvec = TYPE_TI_ARGS (parm);
10027 tree argvec = INNERMOST_TEMPLATE_ARGS (TYPE_TI_ARGS (arg));
10029 = DECL_INNERMOST_TEMPLATE_PARMS (TYPE_TI_TEMPLATE (arg));
10032 /* The parameter and argument roles have to be switched here
10033 in order to handle default arguments properly. For example,
10034 template<template <class> class TT> void f(TT<int>)
10035 should be able to accept vector<int> which comes from
10036 template <class T, class Allocator = allocator>
10039 if (coerce_template_parms (argtmplvec, parmvec, parmtmpl, 0, 1)
10040 == error_mark_node)
10043 /* Deduce arguments T, i from TT<T> or TT<i>.
10044 We check each element of PARMVEC and ARGVEC individually
10045 rather than the whole TREE_VEC since they can have
10046 different number of elements. */
10048 for (i = 0; i < TREE_VEC_LENGTH (parmvec); ++i)
10050 if (unify (tparms, targs,
10051 TREE_VEC_ELT (parmvec, i),
10052 TREE_VEC_ELT (argvec, i),
10057 arg = TYPE_TI_TEMPLATE (arg);
10059 /* Fall through to deduce template name. */
10062 if (TREE_CODE (parm) == TEMPLATE_TEMPLATE_PARM
10063 || TREE_CODE (parm) == BOUND_TEMPLATE_TEMPLATE_PARM)
10065 /* Deduce template name TT from TT, TT<>, TT<T> and TT<i>. */
10067 /* Simple cases: Value already set, does match or doesn't. */
10068 if (targ != NULL_TREE && template_args_equal (targ, arg))
10075 /* If PARM is `const T' and ARG is only `int', we don't have
10076 a match unless we are allowing additional qualification.
10077 If ARG is `const int' and PARM is just `T' that's OK;
10078 that binds `const int' to `T'. */
10079 if (!check_cv_quals_for_unify (strict_in | UNIFY_ALLOW_LESS_CV_QUAL,
10083 /* Consider the case where ARG is `const volatile int' and
10084 PARM is `const T'. Then, T should be `volatile int'. */
10085 arg = cp_build_qualified_type_real
10086 (arg, cp_type_quals (arg) & ~cp_type_quals (parm), tf_none);
10087 if (arg == error_mark_node)
10090 /* Simple cases: Value already set, does match or doesn't. */
10091 if (targ != NULL_TREE && same_type_p (targ, arg))
10096 /* Make sure that ARG is not a variable-sized array. (Note
10097 that were talking about variable-sized arrays (like
10098 `int[n]'), rather than arrays of unknown size (like
10099 `int[]').) We'll get very confused by such a type since
10100 the bound of the array will not be computable in an
10101 instantiation. Besides, such types are not allowed in
10102 ISO C++, so we can do as we please here. */
10103 if (variably_modified_type_p (arg, NULL_TREE))
10107 TREE_VEC_ELT (targs, idx) = arg;
10110 case TEMPLATE_PARM_INDEX:
10111 tparm = TREE_VALUE (TREE_VEC_ELT (tparms, 0));
10113 if (TEMPLATE_PARM_LEVEL (parm)
10114 != template_decl_level (tparm))
10115 /* The PARM is not one we're trying to unify. Just check
10116 to see if it matches ARG. */
10117 return !(TREE_CODE (arg) == TREE_CODE (parm)
10118 && cp_tree_equal (parm, arg));
10120 idx = TEMPLATE_PARM_IDX (parm);
10121 targ = TREE_VEC_ELT (targs, idx);
10124 return !cp_tree_equal (targ, arg);
10126 /* [temp.deduct.type] If, in the declaration of a function template
10127 with a non-type template-parameter, the non-type
10128 template-parameter is used in an expression in the function
10129 parameter-list and, if the corresponding template-argument is
10130 deduced, the template-argument type shall match the type of the
10131 template-parameter exactly, except that a template-argument
10132 deduced from an array bound may be of any integral type.
10133 The non-type parameter might use already deduced type parameters. */
10134 tparm = tsubst (TREE_TYPE (parm), targs, 0, NULL_TREE);
10135 if (!TREE_TYPE (arg))
10136 /* Template-parameter dependent expression. Just accept it for now.
10137 It will later be processed in convert_template_argument. */
10139 else if (same_type_p (TREE_TYPE (arg), tparm))
10141 else if ((strict & UNIFY_ALLOW_INTEGER)
10142 && (TREE_CODE (tparm) == INTEGER_TYPE
10143 || TREE_CODE (tparm) == BOOLEAN_TYPE))
10144 /* Convert the ARG to the type of PARM; the deduced non-type
10145 template argument must exactly match the types of the
10146 corresponding parameter. */
10147 arg = fold (build_nop (TREE_TYPE (parm), arg));
10148 else if (uses_template_parms (tparm))
10149 /* We haven't deduced the type of this parameter yet. Try again
10155 TREE_VEC_ELT (targs, idx) = arg;
10160 /* A pointer-to-member constant can be unified only with
10161 another constant. */
10162 if (TREE_CODE (arg) != PTRMEM_CST)
10165 /* Just unify the class member. It would be useless (and possibly
10166 wrong, depending on the strict flags) to unify also
10167 PTRMEM_CST_CLASS, because we want to be sure that both parm and
10168 arg refer to the same variable, even if through different
10169 classes. For instance:
10171 struct A { int x; };
10174 Unification of &A::x and &B::x must succeed. */
10175 return unify (tparms, targs, PTRMEM_CST_MEMBER (parm),
10176 PTRMEM_CST_MEMBER (arg), strict);
10181 if (TREE_CODE (arg) != POINTER_TYPE)
10184 /* [temp.deduct.call]
10186 A can be another pointer or pointer to member type that can
10187 be converted to the deduced A via a qualification
10188 conversion (_conv.qual_).
10190 We pass down STRICT here rather than UNIFY_ALLOW_NONE.
10191 This will allow for additional cv-qualification of the
10192 pointed-to types if appropriate. */
10194 if (TREE_CODE (TREE_TYPE (arg)) == RECORD_TYPE)
10195 /* The derived-to-base conversion only persists through one
10196 level of pointers. */
10197 strict |= (strict_in & UNIFY_ALLOW_DERIVED);
10199 return unify (tparms, targs, TREE_TYPE (parm),
10200 TREE_TYPE (arg), strict);
10203 case REFERENCE_TYPE:
10204 if (TREE_CODE (arg) != REFERENCE_TYPE)
10206 return unify (tparms, targs, TREE_TYPE (parm), TREE_TYPE (arg),
10207 strict & UNIFY_ALLOW_MORE_CV_QUAL);
10210 if (TREE_CODE (arg) != ARRAY_TYPE)
10212 if ((TYPE_DOMAIN (parm) == NULL_TREE)
10213 != (TYPE_DOMAIN (arg) == NULL_TREE))
10215 if (TYPE_DOMAIN (parm) != NULL_TREE)
10220 parm_max = TYPE_MAX_VALUE (TYPE_DOMAIN (parm));
10221 arg_max = TYPE_MAX_VALUE (TYPE_DOMAIN (arg));
10223 /* Our representation of array types uses "N - 1" as the
10224 TYPE_MAX_VALUE for an array with "N" elements, if "N" is
10225 not an integer constant. */
10226 if (TREE_CODE (parm_max) == MINUS_EXPR)
10228 arg_max = fold_build2 (PLUS_EXPR,
10231 TREE_OPERAND (parm_max, 1));
10232 parm_max = TREE_OPERAND (parm_max, 0);
10235 if (unify (tparms, targs, parm_max, arg_max, UNIFY_ALLOW_INTEGER))
10238 return unify (tparms, targs, TREE_TYPE (parm), TREE_TYPE (arg),
10239 strict & UNIFY_ALLOW_MORE_CV_QUAL);
10246 case ENUMERAL_TYPE:
10248 if (TREE_CODE (arg) != TREE_CODE (parm))
10251 /* We have already checked cv-qualification at the top of the
10253 if (!same_type_ignoring_top_level_qualifiers_p (arg, parm))
10256 /* As far as unification is concerned, this wins. Later checks
10257 will invalidate it if necessary. */
10260 /* Types INTEGER_CST and MINUS_EXPR can come from array bounds. */
10261 /* Type INTEGER_CST can come from ordinary constant template args. */
10263 while (TREE_CODE (arg) == NOP_EXPR)
10264 arg = TREE_OPERAND (arg, 0);
10266 if (TREE_CODE (arg) != INTEGER_CST)
10268 return !tree_int_cst_equal (parm, arg);
10273 if (TREE_CODE (arg) != TREE_VEC)
10275 if (TREE_VEC_LENGTH (parm) != TREE_VEC_LENGTH (arg))
10277 for (i = 0; i < TREE_VEC_LENGTH (parm); ++i)
10278 if (unify (tparms, targs,
10279 TREE_VEC_ELT (parm, i), TREE_VEC_ELT (arg, i),
10287 if (TREE_CODE (arg) != TREE_CODE (parm))
10290 if (TYPE_PTRMEMFUNC_P (parm))
10292 if (!TYPE_PTRMEMFUNC_P (arg))
10295 return unify (tparms, targs,
10296 TYPE_PTRMEMFUNC_FN_TYPE (parm),
10297 TYPE_PTRMEMFUNC_FN_TYPE (arg),
10301 if (CLASSTYPE_TEMPLATE_INFO (parm))
10303 tree t = NULL_TREE;
10305 if (strict_in & UNIFY_ALLOW_DERIVED)
10307 /* First, we try to unify the PARM and ARG directly. */
10308 t = try_class_unification (tparms, targs,
10313 /* Fallback to the special case allowed in
10314 [temp.deduct.call]:
10316 If P is a class, and P has the form
10317 template-id, then A can be a derived class of
10318 the deduced A. Likewise, if P is a pointer to
10319 a class of the form template-id, A can be a
10320 pointer to a derived class pointed to by the
10322 t = get_template_base (tparms, targs, parm, arg);
10328 else if (CLASSTYPE_TEMPLATE_INFO (arg)
10329 && (CLASSTYPE_TI_TEMPLATE (parm)
10330 == CLASSTYPE_TI_TEMPLATE (arg)))
10331 /* Perhaps PARM is something like S<U> and ARG is S<int>.
10332 Then, we should unify `int' and `U'. */
10335 /* There's no chance of unification succeeding. */
10338 return unify (tparms, targs, CLASSTYPE_TI_ARGS (parm),
10339 CLASSTYPE_TI_ARGS (t), UNIFY_ALLOW_NONE);
10341 else if (!same_type_ignoring_top_level_qualifiers_p (parm, arg))
10346 case FUNCTION_TYPE:
10347 if (TREE_CODE (arg) != TREE_CODE (parm))
10350 /* CV qualifications for methods can never be deduced, they must
10351 match exactly. We need to check them explicitly here,
10352 because type_unification_real treats them as any other
10353 cvqualified parameter. */
10354 if (TREE_CODE (parm) == METHOD_TYPE
10355 && (!check_cv_quals_for_unify
10357 TREE_TYPE (TREE_VALUE (TYPE_ARG_TYPES (arg))),
10358 TREE_TYPE (TREE_VALUE (TYPE_ARG_TYPES (parm))))))
10361 if (unify (tparms, targs, TREE_TYPE (parm),
10362 TREE_TYPE (arg), UNIFY_ALLOW_NONE))
10364 return type_unification_real (tparms, targs, TYPE_ARG_TYPES (parm),
10365 TYPE_ARG_TYPES (arg), 1, DEDUCE_EXACT,
10369 /* Unify a pointer to member with a pointer to member function, which
10370 deduces the type of the member as a function type. */
10371 if (TYPE_PTRMEMFUNC_P (arg))
10375 cp_cv_quals cv_quals;
10377 /* Check top-level cv qualifiers */
10378 if (!check_cv_quals_for_unify (UNIFY_ALLOW_NONE, arg, parm))
10381 if (unify (tparms, targs, TYPE_OFFSET_BASETYPE (parm),
10382 TYPE_PTRMEMFUNC_OBJECT_TYPE (arg), UNIFY_ALLOW_NONE))
10385 /* Determine the type of the function we are unifying against. */
10386 method_type = TREE_TYPE (TYPE_PTRMEMFUNC_FN_TYPE (arg));
10388 build_function_type (TREE_TYPE (method_type),
10389 TREE_CHAIN (TYPE_ARG_TYPES (method_type)));
10391 /* Extract the cv-qualifiers of the member function from the
10392 implicit object parameter and place them on the function
10393 type to be restored later. */
10395 cp_type_quals(TREE_TYPE (TREE_VALUE (TYPE_ARG_TYPES (method_type))));
10396 fntype = build_qualified_type (fntype, cv_quals);
10397 return unify (tparms, targs, TREE_TYPE (parm), fntype, strict);
10400 if (TREE_CODE (arg) != OFFSET_TYPE)
10402 if (unify (tparms, targs, TYPE_OFFSET_BASETYPE (parm),
10403 TYPE_OFFSET_BASETYPE (arg), UNIFY_ALLOW_NONE))
10405 return unify (tparms, targs, TREE_TYPE (parm), TREE_TYPE (arg),
10409 if (DECL_TEMPLATE_PARM_P (parm))
10410 return unify (tparms, targs, DECL_INITIAL (parm), arg, strict);
10411 if (arg != integral_constant_value (parm))
10416 case TEMPLATE_DECL:
10417 /* Matched cases are handled by the ARG == PARM test above. */
10421 gcc_assert (EXPR_P (parm));
10423 /* We must be looking at an expression. This can happen with
10427 void foo(S<I>, S<I + 2>);
10429 This is a "nondeduced context":
10433 The nondeduced contexts are:
10435 --A type that is a template-id in which one or more of
10436 the template-arguments is an expression that references
10437 a template-parameter.
10439 In these cases, we assume deduction succeeded, but don't
10440 actually infer any unifications. */
10442 if (!uses_template_parms (parm)
10443 && !template_args_equal (parm, arg))
10450 /* Note that DECL can be defined in this translation unit, if
10454 mark_definable (tree decl)
10457 DECL_NOT_REALLY_EXTERN (decl) = 1;
10458 FOR_EACH_CLONE (clone, decl)
10459 DECL_NOT_REALLY_EXTERN (clone) = 1;
10462 /* Called if RESULT is explicitly instantiated, or is a member of an
10463 explicitly instantiated class. */
10466 mark_decl_instantiated (tree result, int extern_p)
10468 SET_DECL_EXPLICIT_INSTANTIATION (result);
10470 /* If this entity has already been written out, it's too late to
10471 make any modifications. */
10472 if (TREE_ASM_WRITTEN (result))
10475 if (TREE_CODE (result) != FUNCTION_DECL)
10476 /* The TREE_PUBLIC flag for function declarations will have been
10477 set correctly by tsubst. */
10478 TREE_PUBLIC (result) = 1;
10480 /* This might have been set by an earlier implicit instantiation. */
10481 DECL_COMDAT (result) = 0;
10484 DECL_NOT_REALLY_EXTERN (result) = 0;
10487 mark_definable (result);
10488 /* Always make artificials weak. */
10489 if (DECL_ARTIFICIAL (result) && flag_weak)
10490 comdat_linkage (result);
10491 /* For WIN32 we also want to put explicit instantiations in
10492 linkonce sections. */
10493 else if (TREE_PUBLIC (result))
10494 maybe_make_one_only (result);
10497 /* If EXTERN_P, then this function will not be emitted -- unless
10498 followed by an explicit instantiation, at which point its linkage
10499 will be adjusted. If !EXTERN_P, then this function will be
10500 emitted here. In neither circumstance do we want
10501 import_export_decl to adjust the linkage. */
10502 DECL_INTERFACE_KNOWN (result) = 1;
10505 /* Given two function templates PAT1 and PAT2, return:
10507 1 if PAT1 is more specialized than PAT2 as described in [temp.func.order].
10508 -1 if PAT2 is more specialized than PAT1.
10509 0 if neither is more specialized.
10511 LEN indicates the number of parameters we should consider
10512 (defaulted parameters should not be considered).
10514 The 1998 std underspecified function template partial ordering, and
10515 DR214 addresses the issue. We take pairs of arguments, one from
10516 each of the templates, and deduce them against each other. One of
10517 the templates will be more specialized if all the *other*
10518 template's arguments deduce against its arguments and at least one
10519 of its arguments *does* *not* deduce against the other template's
10520 corresponding argument. Deduction is done as for class templates.
10521 The arguments used in deduction have reference and top level cv
10522 qualifiers removed. Iff both arguments were originally reference
10523 types *and* deduction succeeds in both directions, the template
10524 with the more cv-qualified argument wins for that pairing (if
10525 neither is more cv-qualified, they both are equal). Unlike regular
10526 deduction, after all the arguments have been deduced in this way,
10527 we do *not* verify the deduced template argument values can be
10528 substituted into non-deduced contexts, nor do we have to verify
10529 that all template arguments have been deduced. */
10532 more_specialized_fn (tree pat1, tree pat2, int len)
10534 tree decl1 = DECL_TEMPLATE_RESULT (pat1);
10535 tree decl2 = DECL_TEMPLATE_RESULT (pat2);
10536 tree targs1 = make_tree_vec (DECL_NTPARMS (pat1));
10537 tree targs2 = make_tree_vec (DECL_NTPARMS (pat2));
10538 tree tparms1 = DECL_INNERMOST_TEMPLATE_PARMS (pat1);
10539 tree tparms2 = DECL_INNERMOST_TEMPLATE_PARMS (pat2);
10540 tree args1 = TYPE_ARG_TYPES (TREE_TYPE (decl1));
10541 tree args2 = TYPE_ARG_TYPES (TREE_TYPE (decl2));
10545 /* Remove the this parameter from non-static member functions. If
10546 one is a non-static member function and the other is not a static
10547 member function, remove the first parameter from that function
10548 also. This situation occurs for operator functions where we
10549 locate both a member function (with this pointer) and non-member
10550 operator (with explicit first operand). */
10551 if (DECL_NONSTATIC_MEMBER_FUNCTION_P (decl1))
10553 len--; /* LEN is the number of significant arguments for DECL1 */
10554 args1 = TREE_CHAIN (args1);
10555 if (!DECL_STATIC_FUNCTION_P (decl2))
10556 args2 = TREE_CHAIN (args2);
10558 else if (DECL_NONSTATIC_MEMBER_FUNCTION_P (decl2))
10560 args2 = TREE_CHAIN (args2);
10561 if (!DECL_STATIC_FUNCTION_P (decl1))
10564 args1 = TREE_CHAIN (args1);
10568 /* If only one is a conversion operator, they are unordered. */
10569 if (DECL_CONV_FN_P (decl1) != DECL_CONV_FN_P (decl2))
10572 /* Consider the return type for a conversion function */
10573 if (DECL_CONV_FN_P (decl1))
10575 args1 = tree_cons (NULL_TREE, TREE_TYPE (TREE_TYPE (decl1)), args1);
10576 args2 = tree_cons (NULL_TREE, TREE_TYPE (TREE_TYPE (decl2)), args2);
10580 processing_template_decl++;
10584 tree arg1 = TREE_VALUE (args1);
10585 tree arg2 = TREE_VALUE (args2);
10586 int deduce1, deduce2;
10590 if (TREE_CODE (arg1) == REFERENCE_TYPE)
10592 arg1 = TREE_TYPE (arg1);
10593 quals1 = cp_type_quals (arg1);
10596 if (TREE_CODE (arg2) == REFERENCE_TYPE)
10598 arg2 = TREE_TYPE (arg2);
10599 quals2 = cp_type_quals (arg2);
10602 if ((quals1 < 0) != (quals2 < 0))
10604 /* Only of the args is a reference, see if we should apply
10605 array/function pointer decay to it. This is not part of
10606 DR214, but is, IMHO, consistent with the deduction rules
10607 for the function call itself, and with our earlier
10608 implementation of the underspecified partial ordering
10609 rules. (nathan). */
10612 switch (TREE_CODE (arg1))
10615 arg1 = TREE_TYPE (arg1);
10617 case FUNCTION_TYPE:
10618 arg1 = build_pointer_type (arg1);
10627 switch (TREE_CODE (arg2))
10630 arg2 = TREE_TYPE (arg2);
10632 case FUNCTION_TYPE:
10633 arg2 = build_pointer_type (arg2);
10642 arg1 = TYPE_MAIN_VARIANT (arg1);
10643 arg2 = TYPE_MAIN_VARIANT (arg2);
10645 deduce1 = !unify (tparms1, targs1, arg1, arg2, UNIFY_ALLOW_NONE);
10646 deduce2 = !unify (tparms2, targs2, arg2, arg1, UNIFY_ALLOW_NONE);
10652 if (better1 < 0 && better2 < 0)
10653 /* We've failed to deduce something in either direction.
10654 These must be unordered. */
10657 if (deduce1 && deduce2 && quals1 >= 0 && quals2 >= 0)
10659 /* Deduces in both directions, see if quals can
10660 disambiguate. Pretend the worse one failed to deduce. */
10661 if ((quals1 & quals2) == quals2)
10663 if ((quals1 & quals2) == quals1)
10666 if (deduce1 && !deduce2 && !better2)
10668 if (deduce2 && !deduce1 && !better1)
10671 args1 = TREE_CHAIN (args1);
10672 args2 = TREE_CHAIN (args2);
10675 processing_template_decl--;
10677 return (better1 > 0) - (better2 > 0);
10680 /* Given two class template specialization list nodes PAT1 and PAT2, return:
10682 1 if PAT1 is more specialized than PAT2 as described in [temp.class.order].
10683 -1 if PAT2 is more specialized than PAT1.
10684 0 if neither is more specialized.
10686 FULL_ARGS is the full set of template arguments that triggers this
10687 partial ordering. */
10690 more_specialized_class (tree pat1, tree pat2, tree full_args)
10695 /* Just like what happens for functions, if we are ordering between
10696 different class template specializations, we may encounter dependent
10697 types in the arguments, and we need our dependency check functions
10698 to behave correctly. */
10699 ++processing_template_decl;
10700 targs = get_class_bindings (TREE_VALUE (pat1), TREE_PURPOSE (pat1),
10701 add_outermost_template_args (full_args, TREE_PURPOSE (pat2)));
10705 targs = get_class_bindings (TREE_VALUE (pat2), TREE_PURPOSE (pat2),
10706 add_outermost_template_args (full_args, TREE_PURPOSE (pat1)));
10709 --processing_template_decl;
10714 /* Return the template arguments that will produce the function signature
10715 DECL from the function template FN, with the explicit template
10716 arguments EXPLICIT_ARGS. If CHECK_RETTYPE is true, the return type must
10717 also match. Return NULL_TREE if no satisfactory arguments could be
10721 get_bindings (tree fn, tree decl, tree explicit_args, bool check_rettype)
10723 int ntparms = DECL_NTPARMS (fn);
10724 tree targs = make_tree_vec (ntparms);
10726 tree decl_arg_types;
10728 /* Substitute the explicit template arguments into the type of DECL.
10729 The call to fn_type_unification will handle substitution into the
10731 decl_type = TREE_TYPE (decl);
10732 if (explicit_args && uses_template_parms (decl_type))
10735 tree converted_args;
10737 if (DECL_TEMPLATE_INFO (decl))
10738 tmpl = DECL_TI_TEMPLATE (decl);
10740 /* We can get here for some invalid specializations. */
10744 = (coerce_template_parms (DECL_INNERMOST_TEMPLATE_PARMS (tmpl),
10745 explicit_args, NULL_TREE,
10746 tf_none, /*require_all_arguments=*/0));
10747 if (converted_args == error_mark_node)
10750 decl_type = tsubst (decl_type, converted_args, tf_none, NULL_TREE);
10751 if (decl_type == error_mark_node)
10755 decl_arg_types = TYPE_ARG_TYPES (decl_type);
10756 /* Never do unification on the 'this' parameter. */
10757 if (DECL_NONSTATIC_MEMBER_FUNCTION_P (decl))
10758 decl_arg_types = TREE_CHAIN (decl_arg_types);
10760 if (fn_type_unification (fn, explicit_args, targs,
10762 (check_rettype || DECL_CONV_FN_P (fn)
10763 ? TREE_TYPE (decl_type) : NULL_TREE),
10764 DEDUCE_EXACT, LOOKUP_NORMAL))
10770 /* Return the innermost template arguments that, when applied to a
10771 template specialization whose innermost template parameters are
10772 TPARMS, and whose specialization arguments are PARMS, yield the
10775 For example, suppose we have:
10777 template <class T, class U> struct S {};
10778 template <class T> struct S<T*, int> {};
10780 Then, suppose we want to get `S<double*, int>'. The TPARMS will be
10781 {T}, the PARMS will be {T*, int} and the ARGS will be {double*,
10782 int}. The resulting vector will be {double}, indicating that `T'
10783 is bound to `double'. */
10786 get_class_bindings (tree tparms, tree parms, tree args)
10788 int i, ntparms = TREE_VEC_LENGTH (tparms);
10789 tree vec = make_tree_vec (ntparms);
10791 if (unify (tparms, vec, parms, INNERMOST_TEMPLATE_ARGS (args),
10795 for (i = 0; i < ntparms; ++i)
10796 if (! TREE_VEC_ELT (vec, i))
10799 if (verify_class_unification (vec, parms, args))
10805 /* In INSTANTIATIONS is a list of <INSTANTIATION, TEMPLATE> pairs.
10806 Pick the most specialized template, and return the corresponding
10807 instantiation, or if there is no corresponding instantiation, the
10808 template itself. If there is no most specialized template,
10809 error_mark_node is returned. If there are no templates at all,
10810 NULL_TREE is returned. */
10813 most_specialized_instantiation (tree instantiations)
10817 if (!instantiations)
10820 ++processing_template_decl;
10822 champ = instantiations;
10823 for (fn = TREE_CHAIN (instantiations); fn; fn = TREE_CHAIN (fn))
10827 if (get_bindings (TREE_VALUE (champ),
10828 DECL_TEMPLATE_RESULT (TREE_VALUE (fn)),
10829 NULL_TREE, /*check_ret=*/false))
10832 if (get_bindings (TREE_VALUE (fn),
10833 DECL_TEMPLATE_RESULT (TREE_VALUE (champ)),
10834 NULL_TREE, /*check_ret=*/false))
10841 /* Equally specialized, move to next function. If there
10842 is no next function, nothing's most specialized. */
10843 fn = TREE_CHAIN (fn);
10850 /* Now verify that champ is better than everything earlier in the
10851 instantiation list. */
10852 for (fn = instantiations; fn != champ; fn = TREE_CHAIN (fn))
10853 if (get_bindings (TREE_VALUE (champ),
10854 DECL_TEMPLATE_RESULT (TREE_VALUE (fn)),
10855 NULL_TREE, /*check_ret=*/false)
10856 || !get_bindings (TREE_VALUE (fn),
10857 DECL_TEMPLATE_RESULT (TREE_VALUE (champ)),
10858 NULL_TREE, /*check_ret=*/false))
10864 processing_template_decl--;
10867 return error_mark_node;
10869 return TREE_PURPOSE (champ) ? TREE_PURPOSE (champ) : TREE_VALUE (champ);
10872 /* Return the most specialized of the list of templates in FNS that can
10873 produce an instantiation matching DECL, given the explicit template
10874 arguments EXPLICIT_ARGS. */
10877 most_specialized (tree fns, tree decl, tree explicit_args)
10879 tree candidates = NULL_TREE;
10882 for (fn = fns; fn; fn = TREE_CHAIN (fn))
10884 tree candidate = TREE_VALUE (fn);
10886 args = get_bindings (candidate, decl, explicit_args, /*check_ret=*/true);
10888 candidates = tree_cons (NULL_TREE, candidate, candidates);
10891 return most_specialized_instantiation (candidates);
10894 /* If DECL is a specialization of some template, return the most
10895 general such template. Otherwise, returns NULL_TREE.
10897 For example, given:
10899 template <class T> struct S { template <class U> void f(U); };
10901 if TMPL is `template <class U> void S<int>::f(U)' this will return
10902 the full template. This function will not trace past partial
10903 specializations, however. For example, given in addition:
10905 template <class T> struct S<T*> { template <class U> void f(U); };
10907 if TMPL is `template <class U> void S<int*>::f(U)' this will return
10908 `template <class T> template <class U> S<T*>::f(U)'. */
10911 most_general_template (tree decl)
10913 /* If DECL is a FUNCTION_DECL, find the TEMPLATE_DECL of which it is
10914 an immediate specialization. */
10915 if (TREE_CODE (decl) == FUNCTION_DECL)
10917 if (DECL_TEMPLATE_INFO (decl)) {
10918 decl = DECL_TI_TEMPLATE (decl);
10920 /* The DECL_TI_TEMPLATE can be an IDENTIFIER_NODE for a
10921 template friend. */
10922 if (TREE_CODE (decl) != TEMPLATE_DECL)
10928 /* Look for more and more general templates. */
10929 while (DECL_TEMPLATE_INFO (decl))
10931 /* The DECL_TI_TEMPLATE can be an IDENTIFIER_NODE in some cases.
10932 (See cp-tree.h for details.) */
10933 if (TREE_CODE (DECL_TI_TEMPLATE (decl)) != TEMPLATE_DECL)
10936 if (CLASS_TYPE_P (TREE_TYPE (decl))
10937 && CLASSTYPE_TEMPLATE_SPECIALIZATION (TREE_TYPE (decl)))
10940 /* Stop if we run into an explicitly specialized class template. */
10941 if (!DECL_NAMESPACE_SCOPE_P (decl)
10942 && DECL_CONTEXT (decl)
10943 && CLASSTYPE_TEMPLATE_SPECIALIZATION (DECL_CONTEXT (decl)))
10946 decl = DECL_TI_TEMPLATE (decl);
10952 /* Return the most specialized of the class template specializations
10953 of TMPL which can produce an instantiation matching ARGS, or
10954 error_mark_node if the choice is ambiguous. */
10957 most_specialized_class (tree tmpl, tree args)
10959 tree list = NULL_TREE;
10964 tmpl = most_general_template (tmpl);
10965 for (t = DECL_TEMPLATE_SPECIALIZATIONS (tmpl); t; t = TREE_CHAIN (t))
10968 = get_class_bindings (TREE_VALUE (t), TREE_PURPOSE (t), args);
10971 list = tree_cons (TREE_PURPOSE (t), TREE_VALUE (t), list);
10972 TREE_TYPE (list) = TREE_TYPE (t);
10981 t = TREE_CHAIN (t);
10982 for (; t; t = TREE_CHAIN (t))
10984 fate = more_specialized_class (champ, t, args);
10991 t = TREE_CHAIN (t);
10993 return error_mark_node;
10999 for (t = list; t && t != champ; t = TREE_CHAIN (t))
11001 fate = more_specialized_class (champ, t, args);
11003 return error_mark_node;
11009 /* Explicitly instantiate DECL. */
11012 do_decl_instantiation (tree decl, tree storage)
11014 tree result = NULL_TREE;
11018 /* An error occurred, for which grokdeclarator has already issued
11019 an appropriate message. */
11021 else if (! DECL_LANG_SPECIFIC (decl))
11023 error ("explicit instantiation of non-template %q#D", decl);
11026 else if (TREE_CODE (decl) == VAR_DECL)
11028 /* There is an asymmetry here in the way VAR_DECLs and
11029 FUNCTION_DECLs are handled by grokdeclarator. In the case of
11030 the latter, the DECL we get back will be marked as a
11031 template instantiation, and the appropriate
11032 DECL_TEMPLATE_INFO will be set up. This does not happen for
11033 VAR_DECLs so we do the lookup here. Probably, grokdeclarator
11034 should handle VAR_DECLs as it currently handles
11036 result = lookup_field (DECL_CONTEXT (decl), DECL_NAME (decl), 0, false);
11037 if (!result || TREE_CODE (result) != VAR_DECL)
11039 error ("no matching template for %qD found", decl);
11043 else if (TREE_CODE (decl) != FUNCTION_DECL)
11045 error ("explicit instantiation of %q#D", decl);
11051 /* Check for various error cases. Note that if the explicit
11052 instantiation is valid the RESULT will currently be marked as an
11053 *implicit* instantiation; DECL_EXPLICIT_INSTANTIATION is not set
11054 until we get here. */
11056 if (DECL_TEMPLATE_SPECIALIZATION (result))
11058 /* DR 259 [temp.spec].
11060 Both an explicit instantiation and a declaration of an explicit
11061 specialization shall not appear in a program unless the explicit
11062 instantiation follows a declaration of the explicit specialization.
11064 For a given set of template parameters, if an explicit
11065 instantiation of a template appears after a declaration of an
11066 explicit specialization for that template, the explicit
11067 instantiation has no effect. */
11070 else if (DECL_EXPLICIT_INSTANTIATION (result))
11074 No program shall explicitly instantiate any template more
11077 We check DECL_NOT_REALLY_EXTERN so as not to complain when
11078 the first instantiation was `extern' and the second is not,
11079 and EXTERN_P for the opposite case. */
11080 if (DECL_NOT_REALLY_EXTERN (result) && !extern_p)
11081 pedwarn ("duplicate explicit instantiation of %q#D", result);
11082 /* If an "extern" explicit instantiation follows an ordinary
11083 explicit instantiation, the template is instantiated. */
11087 else if (!DECL_IMPLICIT_INSTANTIATION (result))
11089 error ("no matching template for %qD found", result);
11092 else if (!DECL_TEMPLATE_INFO (result))
11094 pedwarn ("explicit instantiation of non-template %q#D", result);
11098 if (storage == NULL_TREE)
11100 else if (storage == ridpointers[(int) RID_EXTERN])
11102 if (pedantic && !in_system_header)
11103 pedwarn ("ISO C++ forbids the use of %<extern%> on explicit "
11108 error ("storage class %qD applied to template instantiation", storage);
11110 check_explicit_instantiation_namespace (result);
11111 mark_decl_instantiated (result, extern_p);
11113 instantiate_decl (result, /*defer_ok=*/1,
11114 /*expl_inst_class_mem_p=*/false);
11118 mark_class_instantiated (tree t, int extern_p)
11120 SET_CLASSTYPE_EXPLICIT_INSTANTIATION (t);
11121 SET_CLASSTYPE_INTERFACE_KNOWN (t);
11122 CLASSTYPE_INTERFACE_ONLY (t) = extern_p;
11123 TYPE_DECL_SUPPRESS_DEBUG (TYPE_NAME (t)) = extern_p;
11126 CLASSTYPE_DEBUG_REQUESTED (t) = 1;
11127 rest_of_type_compilation (t, 1);
11131 /* Called from do_type_instantiation through binding_table_foreach to
11132 do recursive instantiation for the type bound in ENTRY. */
11134 bt_instantiate_type_proc (binding_entry entry, void *data)
11136 tree storage = *(tree *) data;
11138 if (IS_AGGR_TYPE (entry->type)
11139 && !uses_template_parms (CLASSTYPE_TI_ARGS (entry->type)))
11140 do_type_instantiation (TYPE_MAIN_DECL (entry->type), storage, 0);
11143 /* Called from do_type_instantiation to instantiate a member
11144 (a member function or a static member variable) of an
11145 explicitly instantiated class template. */
11147 instantiate_class_member (tree decl, int extern_p)
11149 mark_decl_instantiated (decl, extern_p);
11151 instantiate_decl (decl, /*defer_ok=*/1,
11152 /*expl_inst_class_mem_p=*/true);
11155 /* Perform an explicit instantiation of template class T. STORAGE, if
11156 non-null, is the RID for extern, inline or static. COMPLAIN is
11157 nonzero if this is called from the parser, zero if called recursively,
11158 since the standard is unclear (as detailed below). */
11161 do_type_instantiation (tree t, tree storage, tsubst_flags_t complain)
11166 int previous_instantiation_extern_p = 0;
11168 if (TREE_CODE (t) == TYPE_DECL)
11171 if (! CLASS_TYPE_P (t) || ! CLASSTYPE_TEMPLATE_INFO (t))
11173 error ("explicit instantiation of non-template type %qT", t);
11179 if (!COMPLETE_TYPE_P (t))
11181 if (complain & tf_error)
11182 error ("explicit instantiation of %q#T before definition of template",
11187 if (storage != NULL_TREE)
11189 if (pedantic && !in_system_header)
11190 pedwarn("ISO C++ forbids the use of %qE on explicit instantiations",
11193 if (storage == ridpointers[(int) RID_INLINE])
11195 else if (storage == ridpointers[(int) RID_EXTERN])
11197 else if (storage == ridpointers[(int) RID_STATIC])
11201 error ("storage class %qD applied to template instantiation",
11207 if (CLASSTYPE_TEMPLATE_SPECIALIZATION (t))
11209 /* DR 259 [temp.spec].
11211 Both an explicit instantiation and a declaration of an explicit
11212 specialization shall not appear in a program unless the explicit
11213 instantiation follows a declaration of the explicit specialization.
11215 For a given set of template parameters, if an explicit
11216 instantiation of a template appears after a declaration of an
11217 explicit specialization for that template, the explicit
11218 instantiation has no effect. */
11221 else if (CLASSTYPE_EXPLICIT_INSTANTIATION (t))
11225 No program shall explicitly instantiate any template more
11228 If PREVIOUS_INSTANTIATION_EXTERN_P, then the first explicit
11229 instantiation was `extern'. If EXTERN_P then the second is.
11230 These cases are OK. */
11231 previous_instantiation_extern_p = CLASSTYPE_INTERFACE_ONLY (t);
11233 if (!previous_instantiation_extern_p && !extern_p
11234 && (complain & tf_error))
11235 pedwarn ("duplicate explicit instantiation of %q#T", t);
11237 /* If we've already instantiated the template, just return now. */
11238 if (!CLASSTYPE_INTERFACE_ONLY (t))
11242 check_explicit_instantiation_namespace (TYPE_NAME (t));
11243 mark_class_instantiated (t, extern_p);
11251 /* In contrast to implicit instantiation, where only the
11252 declarations, and not the definitions, of members are
11253 instantiated, we have here:
11257 The explicit instantiation of a class template specialization
11258 implies the instantiation of all of its members not
11259 previously explicitly specialized in the translation unit
11260 containing the explicit instantiation.
11262 Of course, we can't instantiate member template classes, since
11263 we don't have any arguments for them. Note that the standard
11264 is unclear on whether the instantiation of the members are
11265 *explicit* instantiations or not. However, the most natural
11266 interpretation is that it should be an explicit instantiation. */
11269 for (tmp = TYPE_METHODS (t); tmp; tmp = TREE_CHAIN (tmp))
11270 if (TREE_CODE (tmp) == FUNCTION_DECL
11271 && DECL_TEMPLATE_INSTANTIATION (tmp))
11272 instantiate_class_member (tmp, extern_p);
11274 for (tmp = TYPE_FIELDS (t); tmp; tmp = TREE_CHAIN (tmp))
11275 if (TREE_CODE (tmp) == VAR_DECL && DECL_TEMPLATE_INSTANTIATION (tmp))
11276 instantiate_class_member (tmp, extern_p);
11278 if (CLASSTYPE_NESTED_UTDS (t))
11279 binding_table_foreach (CLASSTYPE_NESTED_UTDS (t),
11280 bt_instantiate_type_proc, &storage);
11284 /* Given a function DECL, which is a specialization of TMPL, modify
11285 DECL to be a re-instantiation of TMPL with the same template
11286 arguments. TMPL should be the template into which tsubst'ing
11287 should occur for DECL, not the most general template.
11289 One reason for doing this is a scenario like this:
11292 void f(const T&, int i);
11294 void g() { f(3, 7); }
11297 void f(const T& t, const int i) { }
11299 Note that when the template is first instantiated, with
11300 instantiate_template, the resulting DECL will have no name for the
11301 first parameter, and the wrong type for the second. So, when we go
11302 to instantiate the DECL, we regenerate it. */
11305 regenerate_decl_from_template (tree decl, tree tmpl)
11307 /* The arguments used to instantiate DECL, from the most general
11312 args = DECL_TI_ARGS (decl);
11313 code_pattern = DECL_TEMPLATE_RESULT (tmpl);
11315 /* Make sure that we can see identifiers, and compute access
11317 push_access_scope (decl);
11319 if (TREE_CODE (decl) == FUNCTION_DECL)
11327 args_depth = TMPL_ARGS_DEPTH (args);
11328 parms_depth = TMPL_PARMS_DEPTH (DECL_TEMPLATE_PARMS (tmpl));
11329 if (args_depth > parms_depth)
11330 args = get_innermost_template_args (args, parms_depth);
11332 specs = tsubst_exception_specification (TREE_TYPE (code_pattern),
11333 args, tf_error, NULL_TREE);
11335 TREE_TYPE (decl) = build_exception_variant (TREE_TYPE (decl),
11338 /* Merge parameter declarations. */
11339 decl_parm = skip_artificial_parms_for (decl,
11340 DECL_ARGUMENTS (decl));
11342 = skip_artificial_parms_for (code_pattern,
11343 DECL_ARGUMENTS (code_pattern));
11349 if (DECL_NAME (decl_parm) != DECL_NAME (pattern_parm))
11350 DECL_NAME (decl_parm) = DECL_NAME (pattern_parm);
11351 parm_type = tsubst (TREE_TYPE (pattern_parm), args, tf_error,
11353 parm_type = type_decays_to (parm_type);
11354 if (!same_type_p (TREE_TYPE (decl_parm), parm_type))
11355 TREE_TYPE (decl_parm) = parm_type;
11356 attributes = DECL_ATTRIBUTES (pattern_parm);
11357 if (DECL_ATTRIBUTES (decl_parm) != attributes)
11359 DECL_ATTRIBUTES (decl_parm) = attributes;
11360 cplus_decl_attributes (&decl_parm, attributes, /*flags=*/0);
11362 decl_parm = TREE_CHAIN (decl_parm);
11363 pattern_parm = TREE_CHAIN (pattern_parm);
11366 /* Merge additional specifiers from the CODE_PATTERN. */
11367 if (DECL_DECLARED_INLINE_P (code_pattern)
11368 && !DECL_DECLARED_INLINE_P (decl))
11369 DECL_DECLARED_INLINE_P (decl) = 1;
11370 if (DECL_INLINE (code_pattern) && !DECL_INLINE (decl))
11371 DECL_INLINE (decl) = 1;
11373 else if (TREE_CODE (decl) == VAR_DECL)
11374 DECL_INITIAL (decl) =
11375 tsubst_expr (DECL_INITIAL (code_pattern), args,
11376 tf_error, DECL_TI_TEMPLATE (decl));
11378 gcc_unreachable ();
11380 pop_access_scope (decl);
11383 /* Return the TEMPLATE_DECL into which DECL_TI_ARGS(DECL) should be
11384 substituted to get DECL. */
11387 template_for_substitution (tree decl)
11389 tree tmpl = DECL_TI_TEMPLATE (decl);
11391 /* Set TMPL to the template whose DECL_TEMPLATE_RESULT is the pattern
11392 for the instantiation. This is not always the most general
11393 template. Consider, for example:
11396 struct S { template <class U> void f();
11397 template <> void f<int>(); };
11399 and an instantiation of S<double>::f<int>. We want TD to be the
11400 specialization S<T>::f<int>, not the more general S<T>::f<U>. */
11401 while (/* An instantiation cannot have a definition, so we need a
11402 more general template. */
11403 DECL_TEMPLATE_INSTANTIATION (tmpl)
11404 /* We must also deal with friend templates. Given:
11406 template <class T> struct S {
11407 template <class U> friend void f() {};
11410 S<int>::f<U> say, is not an instantiation of S<T>::f<U>,
11411 so far as the language is concerned, but that's still
11412 where we get the pattern for the instantiation from. On
11413 other hand, if the definition comes outside the class, say:
11415 template <class T> struct S {
11416 template <class U> friend void f();
11418 template <class U> friend void f() {}
11420 we don't need to look any further. That's what the check for
11421 DECL_INITIAL is for. */
11422 || (TREE_CODE (decl) == FUNCTION_DECL
11423 && DECL_FRIEND_PSEUDO_TEMPLATE_INSTANTIATION (tmpl)
11424 && !DECL_INITIAL (DECL_TEMPLATE_RESULT (tmpl))))
11426 /* The present template, TD, should not be a definition. If it
11427 were a definition, we should be using it! Note that we
11428 cannot restructure the loop to just keep going until we find
11429 a template with a definition, since that might go too far if
11430 a specialization was declared, but not defined. */
11431 gcc_assert (TREE_CODE (decl) != VAR_DECL
11432 || DECL_IN_AGGR_P (DECL_TEMPLATE_RESULT (tmpl)));
11434 /* Fetch the more general template. */
11435 tmpl = DECL_TI_TEMPLATE (tmpl);
11441 /* Produce the definition of D, a _DECL generated from a template. If
11442 DEFER_OK is nonzero, then we don't have to actually do the
11443 instantiation now; we just have to do it sometime. Normally it is
11444 an error if this is an explicit instantiation but D is undefined.
11445 EXPL_INST_CLASS_MEM_P is true iff D is a member of an
11446 explicitly instantiated class template. */
11449 instantiate_decl (tree d, int defer_ok,
11450 bool expl_inst_class_mem_p)
11452 tree tmpl = DECL_TI_TEMPLATE (d);
11459 bool pattern_defined;
11461 location_t saved_loc = input_location;
11464 /* This function should only be used to instantiate templates for
11465 functions and static member variables. */
11466 gcc_assert (TREE_CODE (d) == FUNCTION_DECL
11467 || TREE_CODE (d) == VAR_DECL);
11469 /* Variables are never deferred; if instantiation is required, they
11470 are instantiated right away. That allows for better code in the
11471 case that an expression refers to the value of the variable --
11472 if the variable has a constant value the referring expression can
11473 take advantage of that fact. */
11474 if (TREE_CODE (d) == VAR_DECL)
11477 /* Don't instantiate cloned functions. Instead, instantiate the
11478 functions they cloned. */
11479 if (TREE_CODE (d) == FUNCTION_DECL && DECL_CLONED_FUNCTION_P (d))
11480 d = DECL_CLONED_FUNCTION (d);
11482 if (DECL_TEMPLATE_INSTANTIATED (d))
11483 /* D has already been instantiated. It might seem reasonable to
11484 check whether or not D is an explicit instantiation, and, if so,
11485 stop here. But when an explicit instantiation is deferred
11486 until the end of the compilation, DECL_EXPLICIT_INSTANTIATION
11487 is set, even though we still need to do the instantiation. */
11490 /* If we already have a specialization of this declaration, then
11491 there's no reason to instantiate it. Note that
11492 retrieve_specialization gives us both instantiations and
11493 specializations, so we must explicitly check
11494 DECL_TEMPLATE_SPECIALIZATION. */
11495 gen_tmpl = most_general_template (tmpl);
11496 gen_args = DECL_TI_ARGS (d);
11497 spec = retrieve_specialization (gen_tmpl, gen_args,
11498 /*class_specializations_p=*/false);
11499 if (spec != NULL_TREE && DECL_TEMPLATE_SPECIALIZATION (spec))
11502 /* This needs to happen before any tsubsting. */
11503 if (! push_tinst_level (d))
11506 timevar_push (TV_PARSE);
11508 /* Set TD to the template whose DECL_TEMPLATE_RESULT is the pattern
11509 for the instantiation. */
11510 td = template_for_substitution (d);
11511 code_pattern = DECL_TEMPLATE_RESULT (td);
11513 /* We should never be trying to instantiate a member of a class
11514 template or partial specialization. */
11515 gcc_assert (d != code_pattern);
11517 if ((DECL_NAMESPACE_SCOPE_P (d) && !DECL_INITIALIZED_IN_CLASS_P (d))
11518 || DECL_TEMPLATE_SPECIALIZATION (td))
11519 /* In the case of a friend template whose definition is provided
11520 outside the class, we may have too many arguments. Drop the
11521 ones we don't need. The same is true for specializations. */
11522 args = get_innermost_template_args
11523 (gen_args, TMPL_PARMS_DEPTH (DECL_TEMPLATE_PARMS (td)));
11527 if (TREE_CODE (d) == FUNCTION_DECL)
11528 pattern_defined = (DECL_SAVED_TREE (code_pattern) != NULL_TREE);
11530 pattern_defined = ! DECL_IN_AGGR_P (code_pattern);
11532 /* We may be in the middle of deferred access check. Disable it now. */
11533 push_deferring_access_checks (dk_no_deferred);
11535 /* Unless an explicit instantiation directive has already determined
11536 the linkage of D, remember that a definition is available for
11538 if (pattern_defined
11539 && !DECL_INTERFACE_KNOWN (d)
11540 && !DECL_NOT_REALLY_EXTERN (d))
11541 mark_definable (d);
11543 input_location = DECL_SOURCE_LOCATION (d);
11545 /* If D is a member of an explicitly instantiated class template,
11546 and no definition is available, treat it like an implicit
11548 if (!pattern_defined && expl_inst_class_mem_p
11549 && DECL_EXPLICIT_INSTANTIATION (d))
11551 DECL_NOT_REALLY_EXTERN (d) = 0;
11552 DECL_INTERFACE_KNOWN (d) = 0;
11553 SET_DECL_IMPLICIT_INSTANTIATION (d);
11558 /* Recheck the substitutions to obtain any warning messages
11559 about ignoring cv qualifiers. */
11560 tree gen = DECL_TEMPLATE_RESULT (gen_tmpl);
11561 tree type = TREE_TYPE (gen);
11563 /* Make sure that we can see identifiers, and compute access
11564 correctly. D is already the target FUNCTION_DECL with the
11566 push_access_scope (d);
11568 if (TREE_CODE (gen) == FUNCTION_DECL)
11570 tsubst (DECL_ARGUMENTS (gen), gen_args, tf_error | tf_warning, d);
11571 tsubst (TYPE_RAISES_EXCEPTIONS (type), gen_args,
11572 tf_error | tf_warning, d);
11573 /* Don't simply tsubst the function type, as that will give
11574 duplicate warnings about poor parameter qualifications.
11575 The function arguments are the same as the decl_arguments
11576 without the top level cv qualifiers. */
11577 type = TREE_TYPE (type);
11579 tsubst (type, gen_args, tf_error | tf_warning, d);
11581 pop_access_scope (d);
11584 /* Check to see whether we know that this template will be
11585 instantiated in some other file, as with "extern template"
11587 external_p = (DECL_INTERFACE_KNOWN (d) && DECL_REALLY_EXTERN (d));
11588 /* In general, we do not instantiate such templates... */
11590 /* ... but we instantiate inline functions so that we can inline
11592 && ! (TREE_CODE (d) == FUNCTION_DECL && DECL_INLINE (d))
11593 /* ... we instantiate static data members whose values are
11594 needed in integral constant expressions. */
11595 && ! (TREE_CODE (d) == VAR_DECL
11596 && DECL_INITIALIZED_BY_CONSTANT_EXPRESSION_P (d)))
11598 /* Defer all other templates, unless we have been explicitly
11599 forbidden from doing so. */
11600 if (/* If there is no definition, we cannot instantiate the
11603 /* If it's OK to postpone instantiation, do so. */
11605 /* If this is a static data member that will be defined
11606 elsewhere, we don't want to instantiate the entire data
11607 member, but we do want to instantiate the initializer so that
11608 we can substitute that elsewhere. */
11609 || (external_p && TREE_CODE (d) == VAR_DECL))
11611 /* The definition of the static data member is now required so
11612 we must substitute the initializer. */
11613 if (TREE_CODE (d) == VAR_DECL
11614 && !DECL_INITIAL (d)
11615 && DECL_INITIAL (code_pattern))
11620 ns = decl_namespace_context (d);
11621 push_nested_namespace (ns);
11622 push_nested_class (DECL_CONTEXT (d));
11623 init = tsubst_expr (DECL_INITIAL (code_pattern),
11625 tf_error | tf_warning, NULL_TREE);
11626 DECL_INITIAL (d) = NULL_TREE;
11627 finish_static_data_member_decl (d, init,
11628 /*asmspec_tree=*/NULL_TREE,
11629 LOOKUP_ONLYCONVERTING);
11630 pop_nested_class ();
11631 pop_nested_namespace (ns);
11634 /* We restore the source position here because it's used by
11635 add_pending_template. */
11636 input_location = saved_loc;
11638 if (at_eof && !pattern_defined
11639 && DECL_EXPLICIT_INSTANTIATION (d))
11642 The definition of a non-exported function template, a
11643 non-exported member function template, or a non-exported
11644 member function or static data member of a class template
11645 shall be present in every translation unit in which it is
11646 explicitly instantiated. */
11648 ("explicit instantiation of %qD but no definition available", d);
11650 /* ??? Historically, we have instantiated inline functions, even
11651 when marked as "extern template". */
11652 if (!(external_p && TREE_CODE (d) == VAR_DECL))
11653 add_pending_template (d);
11656 /* Tell the repository that D is available in this translation unit
11657 -- and see if it is supposed to be instantiated here. */
11658 if (TREE_PUBLIC (d) && !DECL_REALLY_EXTERN (d) && !repo_emit_p (d))
11660 /* In a PCH file, despite the fact that the repository hasn't
11661 requested instantiation in the PCH it is still possible that
11662 an instantiation will be required in a file that includes the
11665 add_pending_template (d);
11666 /* Instantiate inline functions so that the inliner can do its
11667 job, even though we'll not be emitting a copy of this
11669 if (!(TREE_CODE (d) == FUNCTION_DECL
11670 && flag_inline_trees
11671 && DECL_DECLARED_INLINE_P (d)))
11675 need_push = !cfun || !global_bindings_p ();
11677 push_to_top_level ();
11679 /* Mark D as instantiated so that recursive calls to
11680 instantiate_decl do not try to instantiate it again. */
11681 DECL_TEMPLATE_INSTANTIATED (d) = 1;
11683 /* Regenerate the declaration in case the template has been modified
11684 by a subsequent redeclaration. */
11685 regenerate_decl_from_template (d, td);
11687 /* We already set the file and line above. Reset them now in case
11688 they changed as a result of calling regenerate_decl_from_template. */
11689 input_location = DECL_SOURCE_LOCATION (d);
11691 if (TREE_CODE (d) == VAR_DECL)
11693 /* Clear out DECL_RTL; whatever was there before may not be right
11694 since we've reset the type of the declaration. */
11695 SET_DECL_RTL (d, NULL_RTX);
11696 DECL_IN_AGGR_P (d) = 0;
11698 /* Clear DECL_EXTERNAL so that cp_finish_decl will process the
11699 initializer. That function will defer actual emission until
11700 we have a chance to determine linkage. */
11701 DECL_EXTERNAL (d) = 0;
11703 /* Enter the scope of D so that access-checking works correctly. */
11704 push_nested_class (DECL_CONTEXT (d));
11705 cp_finish_decl (d, DECL_INITIAL (d), NULL_TREE, 0);
11706 pop_nested_class ();
11708 else if (TREE_CODE (d) == FUNCTION_DECL)
11710 htab_t saved_local_specializations;
11715 /* Save away the current list, in case we are instantiating one
11716 template from within the body of another. */
11717 saved_local_specializations = local_specializations;
11719 /* Set up the list of local specializations. */
11720 local_specializations = htab_create (37,
11721 hash_local_specialization,
11722 eq_local_specializations,
11725 /* Set up context. */
11726 start_preparsed_function (d, NULL_TREE, SF_PRE_PARSED);
11728 /* Create substitution entries for the parameters. */
11729 subst_decl = DECL_TEMPLATE_RESULT (template_for_substitution (d));
11730 tmpl_parm = DECL_ARGUMENTS (subst_decl);
11731 spec_parm = DECL_ARGUMENTS (d);
11732 if (DECL_NONSTATIC_MEMBER_FUNCTION_P (d))
11734 register_local_specialization (spec_parm, tmpl_parm);
11735 spec_parm = skip_artificial_parms_for (d, spec_parm);
11736 tmpl_parm = skip_artificial_parms_for (subst_decl, tmpl_parm);
11740 register_local_specialization (spec_parm, tmpl_parm);
11741 tmpl_parm = TREE_CHAIN (tmpl_parm);
11742 spec_parm = TREE_CHAIN (spec_parm);
11744 gcc_assert (!spec_parm);
11746 /* Substitute into the body of the function. */
11747 tsubst_expr (DECL_SAVED_TREE (code_pattern), args,
11748 tf_error | tf_warning, tmpl);
11750 /* We don't need the local specializations any more. */
11751 htab_delete (local_specializations);
11752 local_specializations = saved_local_specializations;
11754 /* Finish the function. */
11755 d = finish_function (0);
11756 expand_or_defer_fn (d);
11759 /* We're not deferring instantiation any more. */
11760 TI_PENDING_TEMPLATE_FLAG (DECL_TEMPLATE_INFO (d)) = 0;
11763 pop_from_top_level ();
11766 input_location = saved_loc;
11767 pop_deferring_access_checks ();
11768 pop_tinst_level ();
11770 timevar_pop (TV_PARSE);
11775 /* Run through the list of templates that we wish we could
11776 instantiate, and instantiate any we can. RETRIES is the
11777 number of times we retry pending template instantiation. */
11780 instantiate_pending_templates (int retries)
11783 tree last = NULL_TREE;
11785 location_t saved_loc = input_location;
11786 int saved_in_system_header = in_system_header;
11788 /* Instantiating templates may trigger vtable generation. This in turn
11789 may require further template instantiations. We place a limit here
11790 to avoid infinite loop. */
11791 if (pending_templates && retries >= max_tinst_depth)
11793 error ("template instantiation depth exceeds maximum of %d"
11794 " instantiating %q+D, possibly from virtual table generation"
11795 " (use -ftemplate-depth-NN to increase the maximum)",
11796 max_tinst_depth, TREE_VALUE (pending_templates));
11804 t = &pending_templates;
11807 tree instantiation = TREE_VALUE (*t);
11809 reopen_tinst_level (TREE_PURPOSE (*t));
11811 if (TYPE_P (instantiation))
11815 if (!COMPLETE_TYPE_P (instantiation))
11817 instantiate_class_template (instantiation);
11818 if (CLASSTYPE_TEMPLATE_INSTANTIATION (instantiation))
11819 for (fn = TYPE_METHODS (instantiation);
11821 fn = TREE_CHAIN (fn))
11822 if (! DECL_ARTIFICIAL (fn))
11823 instantiate_decl (fn,
11825 /*expl_inst_class_mem_p=*/false);
11826 if (COMPLETE_TYPE_P (instantiation))
11830 if (COMPLETE_TYPE_P (instantiation))
11831 /* If INSTANTIATION has been instantiated, then we don't
11832 need to consider it again in the future. */
11833 *t = TREE_CHAIN (*t);
11837 t = &TREE_CHAIN (*t);
11842 if (!DECL_TEMPLATE_SPECIALIZATION (instantiation)
11843 && !DECL_TEMPLATE_INSTANTIATED (instantiation))
11846 = instantiate_decl (instantiation,
11848 /*expl_inst_class_mem_p=*/false);
11849 if (DECL_TEMPLATE_INSTANTIATED (instantiation))
11853 if (DECL_TEMPLATE_SPECIALIZATION (instantiation)
11854 || DECL_TEMPLATE_INSTANTIATED (instantiation))
11855 /* If INSTANTIATION has been instantiated, then we don't
11856 need to consider it again in the future. */
11857 *t = TREE_CHAIN (*t);
11861 t = &TREE_CHAIN (*t);
11865 current_tinst_level = NULL_TREE;
11867 last_pending_template = last;
11869 while (reconsider);
11871 input_location = saved_loc;
11872 in_system_header = saved_in_system_header;
11875 /* Substitute ARGVEC into T, which is a list of initializers for
11876 either base class or a non-static data member. The TREE_PURPOSEs
11877 are DECLs, and the TREE_VALUEs are the initializer values. Used by
11878 instantiate_decl. */
11881 tsubst_initializer_list (tree t, tree argvec)
11883 tree inits = NULL_TREE;
11885 for (; t; t = TREE_CHAIN (t))
11890 decl = tsubst_copy (TREE_PURPOSE (t), argvec, tf_error | tf_warning,
11892 decl = expand_member_init (decl);
11893 if (decl && !DECL_P (decl))
11894 in_base_initializer = 1;
11896 init = tsubst_expr (TREE_VALUE (t), argvec, tf_error | tf_warning,
11898 in_base_initializer = 0;
11902 init = build_tree_list (decl, init);
11903 TREE_CHAIN (init) = inits;
11910 /* Set CURRENT_ACCESS_SPECIFIER based on the protection of DECL. */
11913 set_current_access_from_decl (tree decl)
11915 if (TREE_PRIVATE (decl))
11916 current_access_specifier = access_private_node;
11917 else if (TREE_PROTECTED (decl))
11918 current_access_specifier = access_protected_node;
11920 current_access_specifier = access_public_node;
11923 /* Instantiate an enumerated type. TAG is the template type, NEWTAG
11924 is the instantiation (which should have been created with
11925 start_enum) and ARGS are the template arguments to use. */
11928 tsubst_enum (tree tag, tree newtag, tree args)
11932 for (e = TYPE_VALUES (tag); e; e = TREE_CHAIN (e))
11937 decl = TREE_VALUE (e);
11938 /* Note that in a template enum, the TREE_VALUE is the
11939 CONST_DECL, not the corresponding INTEGER_CST. */
11940 value = tsubst_expr (DECL_INITIAL (decl),
11941 args, tf_error | tf_warning,
11944 /* Give this enumeration constant the correct access. */
11945 set_current_access_from_decl (decl);
11947 /* Actually build the enumerator itself. */
11948 build_enumerator (DECL_NAME (decl), value, newtag);
11951 finish_enum (newtag);
11952 DECL_SOURCE_LOCATION (TYPE_NAME (newtag))
11953 = DECL_SOURCE_LOCATION (TYPE_NAME (tag));
11956 /* DECL is a FUNCTION_DECL that is a template specialization. Return
11957 its type -- but without substituting the innermost set of template
11958 arguments. So, innermost set of template parameters will appear in
11962 get_mostly_instantiated_function_type (tree decl)
11970 tmpl = most_general_template (DECL_TI_TEMPLATE (decl));
11971 targs = DECL_TI_ARGS (decl);
11972 tparms = DECL_TEMPLATE_PARMS (tmpl);
11973 parm_depth = TMPL_PARMS_DEPTH (tparms);
11975 /* There should be as many levels of arguments as there are levels
11977 gcc_assert (parm_depth == TMPL_ARGS_DEPTH (targs));
11979 fn_type = TREE_TYPE (tmpl);
11981 if (parm_depth == 1)
11982 /* No substitution is necessary. */
11986 int i, save_access_control;
11989 /* Replace the innermost level of the TARGS with NULL_TREEs to
11990 let tsubst know not to substitute for those parameters. */
11991 partial_args = make_tree_vec (TREE_VEC_LENGTH (targs));
11992 for (i = 1; i < TMPL_ARGS_DEPTH (targs); ++i)
11993 SET_TMPL_ARGS_LEVEL (partial_args, i,
11994 TMPL_ARGS_LEVEL (targs, i));
11995 SET_TMPL_ARGS_LEVEL (partial_args,
11996 TMPL_ARGS_DEPTH (targs),
11997 make_tree_vec (DECL_NTPARMS (tmpl)));
11999 /* Disable access control as this function is used only during
12001 save_access_control = flag_access_control;
12002 flag_access_control = 0;
12004 ++processing_template_decl;
12005 /* Now, do the (partial) substitution to figure out the
12006 appropriate function type. */
12007 fn_type = tsubst (fn_type, partial_args, tf_error, NULL_TREE);
12008 --processing_template_decl;
12010 /* Substitute into the template parameters to obtain the real
12011 innermost set of parameters. This step is important if the
12012 innermost set of template parameters contains value
12013 parameters whose types depend on outer template parameters. */
12014 TREE_VEC_LENGTH (partial_args)--;
12015 tparms = tsubst_template_parms (tparms, partial_args, tf_error);
12017 flag_access_control = save_access_control;
12023 /* Return truthvalue if we're processing a template different from
12024 the last one involved in diagnostics. */
12026 problematic_instantiation_changed (void)
12028 return last_template_error_tick != tinst_level_tick;
12031 /* Remember current template involved in diagnostics. */
12033 record_last_problematic_instantiation (void)
12035 last_template_error_tick = tinst_level_tick;
12039 current_instantiation (void)
12041 return current_tinst_level;
12044 /* [temp.param] Check that template non-type parm TYPE is of an allowable
12045 type. Return zero for ok, nonzero for disallowed. Issue error and
12046 warning messages under control of COMPLAIN. */
12049 invalid_nontype_parm_type_p (tree type, tsubst_flags_t complain)
12051 if (INTEGRAL_TYPE_P (type))
12053 else if (POINTER_TYPE_P (type))
12055 else if (TYPE_PTR_TO_MEMBER_P (type))
12057 else if (TREE_CODE (type) == TEMPLATE_TYPE_PARM)
12059 else if (TREE_CODE (type) == TYPENAME_TYPE)
12062 if (complain & tf_error)
12063 error ("%q#T is not a valid type for a template constant parameter", type);
12067 /* Returns TRUE if TYPE is dependent, in the sense of [temp.dep.type].
12068 Assumes that TYPE really is a type, and not the ERROR_MARK_NODE.*/
12071 dependent_type_p_r (tree type)
12077 A type is dependent if it is:
12079 -- a template parameter. Template template parameters are types
12080 for us (since TYPE_P holds true for them) so we handle
12082 if (TREE_CODE (type) == TEMPLATE_TYPE_PARM
12083 || TREE_CODE (type) == TEMPLATE_TEMPLATE_PARM)
12085 /* -- a qualified-id with a nested-name-specifier which contains a
12086 class-name that names a dependent type or whose unqualified-id
12087 names a dependent type. */
12088 if (TREE_CODE (type) == TYPENAME_TYPE)
12090 /* -- a cv-qualified type where the cv-unqualified type is
12092 type = TYPE_MAIN_VARIANT (type);
12093 /* -- a compound type constructed from any dependent type. */
12094 if (TYPE_PTR_TO_MEMBER_P (type))
12095 return (dependent_type_p (TYPE_PTRMEM_CLASS_TYPE (type))
12096 || dependent_type_p (TYPE_PTRMEM_POINTED_TO_TYPE
12098 else if (TREE_CODE (type) == POINTER_TYPE
12099 || TREE_CODE (type) == REFERENCE_TYPE)
12100 return dependent_type_p (TREE_TYPE (type));
12101 else if (TREE_CODE (type) == FUNCTION_TYPE
12102 || TREE_CODE (type) == METHOD_TYPE)
12106 if (dependent_type_p (TREE_TYPE (type)))
12108 for (arg_type = TYPE_ARG_TYPES (type);
12110 arg_type = TREE_CHAIN (arg_type))
12111 if (dependent_type_p (TREE_VALUE (arg_type)))
12115 /* -- an array type constructed from any dependent type or whose
12116 size is specified by a constant expression that is
12117 value-dependent. */
12118 if (TREE_CODE (type) == ARRAY_TYPE)
12120 if (TYPE_DOMAIN (type)
12121 && ((value_dependent_expression_p
12122 (TYPE_MAX_VALUE (TYPE_DOMAIN (type))))
12123 || (type_dependent_expression_p
12124 (TYPE_MAX_VALUE (TYPE_DOMAIN (type))))))
12126 return dependent_type_p (TREE_TYPE (type));
12129 /* -- a template-id in which either the template name is a template
12131 if (TREE_CODE (type) == BOUND_TEMPLATE_TEMPLATE_PARM)
12133 /* ... or any of the template arguments is a dependent type or
12134 an expression that is type-dependent or value-dependent. */
12135 else if (CLASS_TYPE_P (type) && CLASSTYPE_TEMPLATE_INFO (type)
12136 && (any_dependent_template_arguments_p
12137 (INNERMOST_TEMPLATE_ARGS (CLASSTYPE_TI_ARGS (type)))))
12140 /* All TYPEOF_TYPEs are dependent; if the argument of the `typeof'
12141 expression is not type-dependent, then it should already been
12143 if (TREE_CODE (type) == TYPEOF_TYPE)
12146 /* The standard does not specifically mention types that are local
12147 to template functions or local classes, but they should be
12148 considered dependent too. For example:
12150 template <int I> void f() {
12155 The size of `E' cannot be known until the value of `I' has been
12156 determined. Therefore, `E' must be considered dependent. */
12157 scope = TYPE_CONTEXT (type);
12158 if (scope && TYPE_P (scope))
12159 return dependent_type_p (scope);
12160 else if (scope && TREE_CODE (scope) == FUNCTION_DECL)
12161 return type_dependent_expression_p (scope);
12163 /* Other types are non-dependent. */
12167 /* Returns TRUE if TYPE is dependent, in the sense of
12168 [temp.dep.type]. */
12171 dependent_type_p (tree type)
12173 /* If there are no template parameters in scope, then there can't be
12174 any dependent types. */
12175 if (!processing_template_decl)
12178 /* If the type is NULL, we have not computed a type for the entity
12179 in question; in that case, the type is dependent. */
12183 /* Erroneous types can be considered non-dependent. */
12184 if (type == error_mark_node)
12187 /* If we have not already computed the appropriate value for TYPE,
12189 if (!TYPE_DEPENDENT_P_VALID (type))
12191 TYPE_DEPENDENT_P (type) = dependent_type_p_r (type);
12192 TYPE_DEPENDENT_P_VALID (type) = 1;
12195 return TYPE_DEPENDENT_P (type);
12198 /* Returns TRUE if EXPRESSION is dependent, according to CRITERION. */
12201 dependent_scope_ref_p (tree expression, bool criterion (tree))
12206 gcc_assert (TREE_CODE (expression) == SCOPE_REF);
12208 if (!TYPE_P (TREE_OPERAND (expression, 0)))
12211 scope = TREE_OPERAND (expression, 0);
12212 name = TREE_OPERAND (expression, 1);
12216 An id-expression is type-dependent if it contains a
12217 nested-name-specifier that contains a class-name that names a
12219 /* The suggested resolution to Core Issue 2 implies that if the
12220 qualifying type is the current class, then we must peek
12223 && currently_open_class (scope)
12224 && !criterion (name))
12226 if (dependent_type_p (scope))
12232 /* Returns TRUE if the EXPRESSION is value-dependent, in the sense of
12233 [temp.dep.constexpr] */
12236 value_dependent_expression_p (tree expression)
12238 if (!processing_template_decl)
12241 /* A name declared with a dependent type. */
12242 if (DECL_P (expression) && type_dependent_expression_p (expression))
12245 switch (TREE_CODE (expression))
12247 case IDENTIFIER_NODE:
12248 /* A name that has not been looked up -- must be dependent. */
12251 case TEMPLATE_PARM_INDEX:
12252 /* A non-type template parm. */
12256 /* A non-type template parm. */
12257 if (DECL_TEMPLATE_PARM_P (expression))
12262 /* A constant with integral or enumeration type and is initialized
12263 with an expression that is value-dependent. */
12264 if (DECL_INITIAL (expression)
12265 && INTEGRAL_OR_ENUMERATION_TYPE_P (TREE_TYPE (expression))
12266 && value_dependent_expression_p (DECL_INITIAL (expression)))
12270 case DYNAMIC_CAST_EXPR:
12271 case STATIC_CAST_EXPR:
12272 case CONST_CAST_EXPR:
12273 case REINTERPRET_CAST_EXPR:
12275 /* These expressions are value-dependent if the type to which
12276 the cast occurs is dependent or the expression being casted
12277 is value-dependent. */
12279 tree type = TREE_TYPE (expression);
12281 if (dependent_type_p (type))
12284 /* A functional cast has a list of operands. */
12285 expression = TREE_OPERAND (expression, 0);
12288 /* If there are no operands, it must be an expression such
12289 as "int()". This should not happen for aggregate types
12290 because it would form non-constant expressions. */
12291 gcc_assert (INTEGRAL_OR_ENUMERATION_TYPE_P (type));
12296 if (TREE_CODE (expression) == TREE_LIST)
12298 for (; expression; expression = TREE_CHAIN (expression))
12299 if (value_dependent_expression_p (TREE_VALUE (expression)))
12304 return value_dependent_expression_p (expression);
12309 /* A `sizeof' expression is value-dependent if the operand is
12311 expression = TREE_OPERAND (expression, 0);
12312 if (TYPE_P (expression))
12313 return dependent_type_p (expression);
12314 return type_dependent_expression_p (expression);
12317 return dependent_scope_ref_p (expression, value_dependent_expression_p);
12319 case COMPONENT_REF:
12320 return (value_dependent_expression_p (TREE_OPERAND (expression, 0))
12321 || value_dependent_expression_p (TREE_OPERAND (expression, 1)));
12324 /* A CALL_EXPR is value-dependent if any argument is
12325 value-dependent. Why do we have to handle CALL_EXPRs in this
12326 function at all? First, some function calls, those for which
12327 value_dependent_expression_p is true, man appear in constant
12328 expressions. Second, there appear to be bugs which result in
12329 other CALL_EXPRs reaching this point. */
12331 tree function = TREE_OPERAND (expression, 0);
12332 tree args = TREE_OPERAND (expression, 1);
12334 if (value_dependent_expression_p (function))
12340 if (TREE_CODE (args) == TREE_LIST)
12342 for (; args; args = TREE_CHAIN (args))
12343 if (value_dependent_expression_p (TREE_VALUE (args)))
12348 return value_dependent_expression_p (args);
12352 /* A constant expression is value-dependent if any subexpression is
12353 value-dependent. */
12354 switch (TREE_CODE_CLASS (TREE_CODE (expression)))
12356 case tcc_reference:
12358 return (value_dependent_expression_p
12359 (TREE_OPERAND (expression, 0)));
12361 case tcc_comparison:
12363 return ((value_dependent_expression_p
12364 (TREE_OPERAND (expression, 0)))
12365 || (value_dependent_expression_p
12366 (TREE_OPERAND (expression, 1))));
12368 case tcc_expression:
12371 for (i = 0; i < TREE_CODE_LENGTH (TREE_CODE (expression)); ++i)
12372 /* In some cases, some of the operands may be missing.
12373 (For example, in the case of PREDECREMENT_EXPR, the
12374 amount to increment by may be missing.) That doesn't
12375 make the expression dependent. */
12376 if (TREE_OPERAND (expression, i)
12377 && (value_dependent_expression_p
12378 (TREE_OPERAND (expression, i))))
12388 /* The expression is not value-dependent. */
12392 /* Returns TRUE if the EXPRESSION is type-dependent, in the sense of
12393 [temp.dep.expr]. */
12396 type_dependent_expression_p (tree expression)
12398 if (!processing_template_decl)
12401 if (expression == error_mark_node)
12404 /* An unresolved name is always dependent. */
12405 if (TREE_CODE (expression) == IDENTIFIER_NODE)
12408 /* Some expression forms are never type-dependent. */
12409 if (TREE_CODE (expression) == PSEUDO_DTOR_EXPR
12410 || TREE_CODE (expression) == SIZEOF_EXPR
12411 || TREE_CODE (expression) == ALIGNOF_EXPR
12412 || TREE_CODE (expression) == TYPEID_EXPR
12413 || TREE_CODE (expression) == DELETE_EXPR
12414 || TREE_CODE (expression) == VEC_DELETE_EXPR
12415 || TREE_CODE (expression) == THROW_EXPR)
12418 /* The types of these expressions depends only on the type to which
12419 the cast occurs. */
12420 if (TREE_CODE (expression) == DYNAMIC_CAST_EXPR
12421 || TREE_CODE (expression) == STATIC_CAST_EXPR
12422 || TREE_CODE (expression) == CONST_CAST_EXPR
12423 || TREE_CODE (expression) == REINTERPRET_CAST_EXPR
12424 || TREE_CODE (expression) == CAST_EXPR)
12425 return dependent_type_p (TREE_TYPE (expression));
12427 /* The types of these expressions depends only on the type created
12428 by the expression. */
12429 if (TREE_CODE (expression) == NEW_EXPR
12430 || TREE_CODE (expression) == VEC_NEW_EXPR)
12432 /* For NEW_EXPR tree nodes created inside a template, either
12433 the object type itself or a TREE_LIST may appear as the
12435 tree type = TREE_OPERAND (expression, 1);
12436 if (TREE_CODE (type) == TREE_LIST)
12437 /* This is an array type. We need to check array dimensions
12439 return dependent_type_p (TREE_VALUE (TREE_PURPOSE (type)))
12440 || value_dependent_expression_p
12441 (TREE_OPERAND (TREE_VALUE (type), 1));
12443 return dependent_type_p (type);
12446 if (TREE_CODE (expression) == SCOPE_REF
12447 && dependent_scope_ref_p (expression,
12448 type_dependent_expression_p))
12451 if (TREE_CODE (expression) == FUNCTION_DECL
12452 && DECL_LANG_SPECIFIC (expression)
12453 && DECL_TEMPLATE_INFO (expression)
12454 && (any_dependent_template_arguments_p
12455 (INNERMOST_TEMPLATE_ARGS (DECL_TI_ARGS (expression)))))
12458 if (TREE_CODE (expression) == TEMPLATE_DECL
12459 && !DECL_TEMPLATE_TEMPLATE_PARM_P (expression))
12462 if (TREE_TYPE (expression) == unknown_type_node)
12464 if (TREE_CODE (expression) == ADDR_EXPR)
12465 return type_dependent_expression_p (TREE_OPERAND (expression, 0));
12466 if (TREE_CODE (expression) == COMPONENT_REF
12467 || TREE_CODE (expression) == OFFSET_REF)
12469 if (type_dependent_expression_p (TREE_OPERAND (expression, 0)))
12471 expression = TREE_OPERAND (expression, 1);
12472 if (TREE_CODE (expression) == IDENTIFIER_NODE)
12475 /* SCOPE_REF with non-null TREE_TYPE is always non-dependent. */
12476 if (TREE_CODE (expression) == SCOPE_REF)
12479 if (TREE_CODE (expression) == BASELINK)
12480 expression = BASELINK_FUNCTIONS (expression);
12482 if (TREE_CODE (expression) == TEMPLATE_ID_EXPR)
12484 if (any_dependent_template_arguments_p
12485 (TREE_OPERAND (expression, 1)))
12487 expression = TREE_OPERAND (expression, 0);
12489 gcc_assert (TREE_CODE (expression) == OVERLOAD
12490 || TREE_CODE (expression) == FUNCTION_DECL);
12494 if (type_dependent_expression_p (OVL_CURRENT (expression)))
12496 expression = OVL_NEXT (expression);
12501 gcc_assert (TREE_CODE (expression) != TYPE_DECL);
12503 return (dependent_type_p (TREE_TYPE (expression)));
12506 /* Returns TRUE if ARGS (a TREE_LIST of arguments to a function call)
12507 contains a type-dependent expression. */
12510 any_type_dependent_arguments_p (tree args)
12514 tree arg = TREE_VALUE (args);
12516 if (type_dependent_expression_p (arg))
12518 args = TREE_CHAIN (args);
12523 /* Returns TRUE if the ARG (a template argument) is dependent. */
12526 dependent_template_arg_p (tree arg)
12528 if (!processing_template_decl)
12531 if (TREE_CODE (arg) == TEMPLATE_DECL
12532 || TREE_CODE (arg) == TEMPLATE_TEMPLATE_PARM)
12533 return dependent_template_p (arg);
12534 else if (TYPE_P (arg))
12535 return dependent_type_p (arg);
12537 return (type_dependent_expression_p (arg)
12538 || value_dependent_expression_p (arg));
12541 /* Returns true if ARGS (a collection of template arguments) contains
12542 any dependent arguments. */
12545 any_dependent_template_arguments_p (tree args)
12553 for (i = 0; i < TMPL_ARGS_DEPTH (args); ++i)
12555 tree level = TMPL_ARGS_LEVEL (args, i + 1);
12556 for (j = 0; j < TREE_VEC_LENGTH (level); ++j)
12557 if (dependent_template_arg_p (TREE_VEC_ELT (level, j)))
12564 /* Returns TRUE if the template TMPL is dependent. */
12567 dependent_template_p (tree tmpl)
12569 if (TREE_CODE (tmpl) == OVERLOAD)
12573 if (dependent_template_p (OVL_FUNCTION (tmpl)))
12575 tmpl = OVL_CHAIN (tmpl);
12580 /* Template template parameters are dependent. */
12581 if (DECL_TEMPLATE_TEMPLATE_PARM_P (tmpl)
12582 || TREE_CODE (tmpl) == TEMPLATE_TEMPLATE_PARM)
12584 /* So are names that have not been looked up. */
12585 if (TREE_CODE (tmpl) == SCOPE_REF
12586 || TREE_CODE (tmpl) == IDENTIFIER_NODE)
12588 /* So are member templates of dependent classes. */
12589 if (TYPE_P (CP_DECL_CONTEXT (tmpl)))
12590 return dependent_type_p (DECL_CONTEXT (tmpl));
12594 /* Returns TRUE if the specialization TMPL<ARGS> is dependent. */
12597 dependent_template_id_p (tree tmpl, tree args)
12599 return (dependent_template_p (tmpl)
12600 || any_dependent_template_arguments_p (args));
12603 /* TYPE is a TYPENAME_TYPE. Returns the ordinary TYPE to which the
12604 TYPENAME_TYPE corresponds. Returns ERROR_MARK_NODE if no such TYPE
12605 can be found. Note that this function peers inside uninstantiated
12606 templates and therefore should be used only in extremely limited
12607 situations. ONLY_CURRENT_P restricts this peering to the currently
12608 open classes hierarchy (which is required when comparing types). */
12611 resolve_typename_type (tree type, bool only_current_p)
12619 gcc_assert (TREE_CODE (type) == TYPENAME_TYPE);
12621 scope = TYPE_CONTEXT (type);
12622 name = TYPE_IDENTIFIER (type);
12624 /* If the SCOPE is itself a TYPENAME_TYPE, then we need to resolve
12625 it first before we can figure out what NAME refers to. */
12626 if (TREE_CODE (scope) == TYPENAME_TYPE)
12627 scope = resolve_typename_type (scope, only_current_p);
12628 /* If we don't know what SCOPE refers to, then we cannot resolve the
12630 if (scope == error_mark_node || TREE_CODE (scope) == TYPENAME_TYPE)
12631 return error_mark_node;
12632 /* If the SCOPE is a template type parameter, we have no way of
12633 resolving the name. */
12634 if (TREE_CODE (scope) == TEMPLATE_TYPE_PARM)
12636 /* If the SCOPE is not the current instantiation, there's no reason
12637 to look inside it. */
12638 if (only_current_p && !currently_open_class (scope))
12639 return error_mark_node;
12640 /* If SCOPE is a partial instantiation, it will not have a valid
12641 TYPE_FIELDS list, so use the original template. */
12642 scope = CLASSTYPE_PRIMARY_TEMPLATE_TYPE (scope);
12643 /* Enter the SCOPE so that name lookup will be resolved as if we
12644 were in the class definition. In particular, SCOPE will no
12645 longer be considered a dependent type. */
12646 pushed_scope = push_scope (scope);
12647 /* Look up the declaration. */
12648 decl = lookup_member (scope, name, /*protect=*/0, /*want_type=*/true);
12649 /* Obtain the set of qualifiers applied to the TYPE. */
12650 quals = cp_type_quals (type);
12651 /* For a TYPENAME_TYPE like "typename X::template Y<T>", we want to
12652 find a TEMPLATE_DECL. Otherwise, we want to find a TYPE_DECL. */
12654 type = error_mark_node;
12655 else if (TREE_CODE (TYPENAME_TYPE_FULLNAME (type)) == IDENTIFIER_NODE
12656 && TREE_CODE (decl) == TYPE_DECL)
12657 type = TREE_TYPE (decl);
12658 else if (TREE_CODE (TYPENAME_TYPE_FULLNAME (type)) == TEMPLATE_ID_EXPR
12659 && DECL_CLASS_TEMPLATE_P (decl))
12663 /* Obtain the template and the arguments. */
12664 tmpl = TREE_OPERAND (TYPENAME_TYPE_FULLNAME (type), 0);
12665 args = TREE_OPERAND (TYPENAME_TYPE_FULLNAME (type), 1);
12666 /* Instantiate the template. */
12667 type = lookup_template_class (tmpl, args, NULL_TREE, NULL_TREE,
12668 /*entering_scope=*/0, tf_error | tf_user);
12671 type = error_mark_node;
12672 /* Qualify the resulting type. */
12673 if (type != error_mark_node && quals)
12674 type = cp_build_qualified_type (type, quals);
12675 /* Leave the SCOPE. */
12677 pop_scope (pushed_scope);
12682 /* EXPR is an expression which is not type-dependent. Return a proxy
12683 for EXPR that can be used to compute the types of larger
12684 expressions containing EXPR. */
12687 build_non_dependent_expr (tree expr)
12691 /* Preserve null pointer constants so that the type of things like
12692 "p == 0" where "p" is a pointer can be determined. */
12693 if (null_ptr_cst_p (expr))
12695 /* Preserve OVERLOADs; the functions must be available to resolve
12697 inner_expr = (TREE_CODE (expr) == ADDR_EXPR ?
12698 TREE_OPERAND (expr, 0) :
12699 TREE_CODE (expr) == COMPONENT_REF ?
12700 TREE_OPERAND (expr, 1) : expr);
12701 if (is_overloaded_fn (inner_expr)
12702 || TREE_CODE (inner_expr) == OFFSET_REF)
12704 /* There is no need to return a proxy for a variable. */
12705 if (TREE_CODE (expr) == VAR_DECL)
12707 /* Preserve string constants; conversions from string constants to
12708 "char *" are allowed, even though normally a "const char *"
12709 cannot be used to initialize a "char *". */
12710 if (TREE_CODE (expr) == STRING_CST)
12712 /* Preserve arithmetic constants, as an optimization -- there is no
12713 reason to create a new node. */
12714 if (TREE_CODE (expr) == INTEGER_CST || TREE_CODE (expr) == REAL_CST)
12716 /* Preserve THROW_EXPRs -- all throw-expressions have type "void".
12717 There is at least one place where we want to know that a
12718 particular expression is a throw-expression: when checking a ?:
12719 expression, there are special rules if the second or third
12720 argument is a throw-expression. */
12721 if (TREE_CODE (expr) == THROW_EXPR)
12724 if (TREE_CODE (expr) == COND_EXPR)
12725 return build3 (COND_EXPR,
12727 TREE_OPERAND (expr, 0),
12728 (TREE_OPERAND (expr, 1)
12729 ? build_non_dependent_expr (TREE_OPERAND (expr, 1))
12730 : build_non_dependent_expr (TREE_OPERAND (expr, 0))),
12731 build_non_dependent_expr (TREE_OPERAND (expr, 2)));
12732 if (TREE_CODE (expr) == COMPOUND_EXPR
12733 && !COMPOUND_EXPR_OVERLOADED (expr))
12734 return build2 (COMPOUND_EXPR,
12736 TREE_OPERAND (expr, 0),
12737 build_non_dependent_expr (TREE_OPERAND (expr, 1)));
12739 /* If the type is unknown, it can't really be non-dependent */
12740 gcc_assert (TREE_TYPE (expr) != unknown_type_node);
12742 /* Otherwise, build a NON_DEPENDENT_EXPR.
12744 REFERENCE_TYPEs are not stripped for expressions in templates
12745 because doing so would play havoc with mangling. Consider, for
12748 template <typename T> void f<T& g>() { g(); }
12750 In the body of "f", the expression for "g" will have
12751 REFERENCE_TYPE, even though the standard says that it should
12752 not. The reason is that we must preserve the syntactic form of
12753 the expression so that mangling (say) "f<g>" inside the body of
12754 "f" works out correctly. Therefore, the REFERENCE_TYPE is
12756 return build1 (NON_DEPENDENT_EXPR, non_reference (TREE_TYPE (expr)), expr);
12759 /* ARGS is a TREE_LIST of expressions as arguments to a function call.
12760 Return a new TREE_LIST with the various arguments replaced with
12761 equivalent non-dependent expressions. */
12764 build_non_dependent_args (tree args)
12769 new_args = NULL_TREE;
12770 for (a = args; a; a = TREE_CHAIN (a))
12771 new_args = tree_cons (NULL_TREE,
12772 build_non_dependent_expr (TREE_VALUE (a)),
12774 return nreverse (new_args);
12777 #include "gt-cp-pt.h"