1 /* Handle parameterized types (templates) for GNU C++.
2 Copyright (C) 1992, 1993, 1994, 1995, 1996, 1997, 1998, 1999, 2000,
3 2001, 2002, 2003 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, 59 Temple Place - Suite 330,
22 Boston, MA 02111-1307, 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"
37 #include "tree-inline.h"
46 /* The type of functions taking a tree, and some additional data, and
48 typedef int (*tree_fn_t) (tree, void*);
50 /* The PENDING_TEMPLATES is a TREE_LIST of templates whose
51 instantiations have been deferred, either because their definitions
52 were not yet available, or because we were putting off doing the work.
53 The TREE_PURPOSE of each entry is either a DECL (for a function or
54 static data member), or a TYPE (for a class) indicating what we are
55 hoping to instantiate. The TREE_VALUE is not used. */
56 static GTY(()) tree pending_templates;
57 static GTY(()) tree last_pending_template;
59 int processing_template_parmlist;
60 static int template_header_count;
62 static GTY(()) tree saved_trees;
63 static GTY(()) varray_type inline_parm_levels;
64 static size_t inline_parm_levels_used;
66 static GTY(()) tree current_tinst_level;
68 static GTY(()) tree saved_access_scope;
70 /* A map from local variable declarations in the body of the template
71 presently being instantiated to the corresponding instantiated
73 static htab_t local_specializations;
75 #define UNIFY_ALLOW_NONE 0
76 #define UNIFY_ALLOW_MORE_CV_QUAL 1
77 #define UNIFY_ALLOW_LESS_CV_QUAL 2
78 #define UNIFY_ALLOW_DERIVED 4
79 #define UNIFY_ALLOW_INTEGER 8
80 #define UNIFY_ALLOW_OUTER_LEVEL 16
81 #define UNIFY_ALLOW_OUTER_MORE_CV_QUAL 32
82 #define UNIFY_ALLOW_OUTER_LESS_CV_QUAL 64
83 #define UNIFY_ALLOW_MAX_CORRECTION 128
85 #define GTB_VIA_VIRTUAL 1 /* The base class we are examining is
86 virtual, or a base class of a virtual
88 #define GTB_IGNORE_TYPE 2 /* We don't need to try to unify the current
89 type with the desired type. */
91 static void push_access_scope (tree);
92 static void pop_access_scope (tree);
93 static int resolve_overloaded_unification (tree, tree, tree, tree,
94 unification_kind_t, int);
95 static int try_one_overload (tree, tree, tree, tree, tree,
96 unification_kind_t, int, bool);
97 static int unify (tree, tree, tree, tree, int);
98 static void add_pending_template (tree);
99 static void reopen_tinst_level (tree);
100 static tree classtype_mangled_name (tree);
101 static char* mangle_class_name_for_template (const char *, tree, tree);
102 static tree tsubst_initializer_list (tree, tree);
103 static tree get_class_bindings (tree, tree, tree);
104 static tree coerce_template_parms (tree, tree, tree, tsubst_flags_t, int);
105 static void tsubst_enum (tree, tree, tree);
106 static tree add_to_template_args (tree, tree);
107 static tree add_outermost_template_args (tree, tree);
108 static bool check_instantiated_args (tree, tree, tsubst_flags_t);
109 static int maybe_adjust_types_for_deduction (unification_kind_t, tree*, tree*);
110 static int type_unification_real (tree, tree, tree, tree,
111 int, unification_kind_t, int, int);
112 static void note_template_header (int);
113 static tree convert_nontype_argument (tree, tree);
114 static tree convert_template_argument (tree, tree, tree,
115 tsubst_flags_t, int, tree);
116 static tree get_bindings_overload (tree, tree, tree);
117 static int for_each_template_parm (tree, tree_fn_t, void*, htab_t);
118 static tree build_template_parm_index (int, int, int, tree, tree);
119 static int inline_needs_template_parms (tree);
120 static void push_inline_template_parms_recursive (tree, int);
121 static tree retrieve_specialization (tree, tree);
122 static tree retrieve_local_specialization (tree);
123 static tree register_specialization (tree, tree, tree);
124 static void register_local_specialization (tree, tree);
125 static tree reduce_template_parm_level (tree, tree, int);
126 static tree build_template_decl (tree, tree);
127 static int mark_template_parm (tree, void *);
128 static int template_parm_this_level_p (tree, void *);
129 static tree tsubst_friend_function (tree, tree);
130 static tree tsubst_friend_class (tree, tree);
131 static int can_complete_type_without_circularity (tree);
132 static tree get_bindings (tree, tree, tree);
133 static tree get_bindings_real (tree, tree, tree, int, int, int);
134 static int template_decl_level (tree);
135 static int check_cv_quals_for_unify (int, tree, tree);
136 static tree tsubst_template_arg (tree, tree, tsubst_flags_t, tree);
137 static tree tsubst_template_args (tree, tree, tsubst_flags_t, tree);
138 static tree tsubst_template_parms (tree, tree, tsubst_flags_t);
139 static void regenerate_decl_from_template (tree, tree);
140 static tree most_specialized (tree, tree, tree);
141 static tree most_specialized_class (tree, tree);
142 static int template_class_depth_real (tree, int);
143 static tree tsubst_aggr_type (tree, tree, tsubst_flags_t, tree, int);
144 static tree tsubst_decl (tree, tree, tree, tsubst_flags_t);
145 static tree tsubst_arg_types (tree, tree, tsubst_flags_t, tree);
146 static tree tsubst_function_type (tree, tree, tsubst_flags_t, tree);
147 static void check_specialization_scope (void);
148 static tree process_partial_specialization (tree);
149 static void set_current_access_from_decl (tree);
150 static void check_default_tmpl_args (tree, tree, int, int);
151 static tree tsubst_call_declarator_parms (tree, tree, tsubst_flags_t, tree);
152 static tree get_template_base_recursive (tree, tree, tree, tree, tree, int);
153 static tree get_template_base (tree, tree, tree, tree);
154 static int verify_class_unification (tree, tree, tree);
155 static tree try_class_unification (tree, tree, tree, tree);
156 static int coerce_template_template_parms (tree, tree, tsubst_flags_t,
158 static tree determine_specialization (tree, tree, tree *, int);
159 static int template_args_equal (tree, tree);
160 static void tsubst_default_arguments (tree);
161 static tree for_each_template_parm_r (tree *, int *, void *);
162 static tree copy_default_args_to_explicit_spec_1 (tree, tree);
163 static void copy_default_args_to_explicit_spec (tree);
164 static int invalid_nontype_parm_type_p (tree, tsubst_flags_t);
165 static int eq_local_specializations (const void *, const void *);
166 static bool dependent_type_p_r (tree);
167 static tree tsubst (tree, tree, tsubst_flags_t, tree);
168 static tree tsubst_expr (tree, tree, tsubst_flags_t, tree);
169 static tree tsubst_copy (tree, tree, tsubst_flags_t, tree);
171 /* Make the current scope suitable for access checking when we are
172 processing T. T can be FUNCTION_DECL for instantiated function
173 template, or VAR_DECL for static member variable (need by
174 instantiate_decl). */
177 push_access_scope (tree t)
179 my_friendly_assert (TREE_CODE (t) == FUNCTION_DECL
180 || TREE_CODE (t) == VAR_DECL,
183 if (DECL_CLASS_SCOPE_P (t))
184 push_nested_class (DECL_CONTEXT (t));
186 push_to_top_level ();
188 if (TREE_CODE (t) == FUNCTION_DECL)
190 saved_access_scope = tree_cons
191 (NULL_TREE, current_function_decl, saved_access_scope);
192 current_function_decl = t;
196 /* Restore the scope set up by push_access_scope. T is the node we
200 pop_access_scope (tree t)
202 if (TREE_CODE (t) == FUNCTION_DECL)
204 current_function_decl = TREE_VALUE (saved_access_scope);
205 saved_access_scope = TREE_CHAIN (saved_access_scope);
208 if (DECL_CLASS_SCOPE_P (t))
211 pop_from_top_level ();
214 /* Do any processing required when DECL (a member template
215 declaration) is finished. Returns the TEMPLATE_DECL corresponding
216 to DECL, unless it is a specialization, in which case the DECL
217 itself is returned. */
220 finish_member_template_decl (tree decl)
222 if (decl == error_mark_node)
223 return error_mark_node;
225 my_friendly_assert (DECL_P (decl), 20020812);
227 if (TREE_CODE (decl) == TYPE_DECL)
231 type = TREE_TYPE (decl);
232 if (IS_AGGR_TYPE (type)
233 && CLASSTYPE_TEMPLATE_INFO (type)
234 && !CLASSTYPE_TEMPLATE_SPECIALIZATION (type))
236 tree tmpl = CLASSTYPE_TI_TEMPLATE (type);
237 check_member_template (tmpl);
242 else if (TREE_CODE (decl) == FIELD_DECL)
243 error ("data member `%D' cannot be a member template", decl);
244 else if (DECL_TEMPLATE_INFO (decl))
246 if (!DECL_TEMPLATE_SPECIALIZATION (decl))
248 check_member_template (DECL_TI_TEMPLATE (decl));
249 return DECL_TI_TEMPLATE (decl);
255 error ("invalid member template declaration `%D'", decl);
257 return error_mark_node;
260 /* Returns the template nesting level of the indicated class TYPE.
270 A<T>::B<U> has depth two, while A<T> has depth one.
271 Both A<T>::B<int> and A<int>::B<U> have depth one, if
272 COUNT_SPECIALIZATIONS is 0 or if they are instantiations, not
275 This function is guaranteed to return 0 if passed NULL_TREE so
276 that, for example, `template_class_depth (current_class_type)' is
280 template_class_depth_real (tree type, int count_specializations)
285 type && TREE_CODE (type) != NAMESPACE_DECL;
286 type = (TREE_CODE (type) == FUNCTION_DECL)
287 ? CP_DECL_CONTEXT (type) : TYPE_CONTEXT (type))
289 if (TREE_CODE (type) != FUNCTION_DECL)
291 if (CLASSTYPE_TEMPLATE_INFO (type)
292 && PRIMARY_TEMPLATE_P (CLASSTYPE_TI_TEMPLATE (type))
293 && ((count_specializations
294 && CLASSTYPE_TEMPLATE_SPECIALIZATION (type))
295 || uses_template_parms (CLASSTYPE_TI_ARGS (type))))
300 if (DECL_TEMPLATE_INFO (type)
301 && PRIMARY_TEMPLATE_P (DECL_TI_TEMPLATE (type))
302 && ((count_specializations
303 && DECL_TEMPLATE_SPECIALIZATION (type))
304 || uses_template_parms (DECL_TI_ARGS (type))))
312 /* Returns the template nesting level of the indicated class TYPE.
313 Like template_class_depth_real, but instantiations do not count in
317 template_class_depth (tree type)
319 return template_class_depth_real (type, /*count_specializations=*/0);
322 /* Returns 1 if processing DECL as part of do_pending_inlines
323 needs us to push template parms. */
326 inline_needs_template_parms (tree decl)
328 if (! DECL_TEMPLATE_INFO (decl))
331 return (TMPL_PARMS_DEPTH (DECL_TEMPLATE_PARMS (most_general_template (decl)))
332 > (processing_template_decl + DECL_TEMPLATE_SPECIALIZATION (decl)));
335 /* Subroutine of maybe_begin_member_template_processing.
336 Push the template parms in PARMS, starting from LEVELS steps into the
337 chain, and ending at the beginning, since template parms are listed
341 push_inline_template_parms_recursive (tree parmlist, int levels)
343 tree parms = TREE_VALUE (parmlist);
347 push_inline_template_parms_recursive (TREE_CHAIN (parmlist), levels - 1);
349 ++processing_template_decl;
350 current_template_parms
351 = tree_cons (size_int (processing_template_decl),
352 parms, current_template_parms);
353 TEMPLATE_PARMS_FOR_INLINE (current_template_parms) = 1;
356 for (i = 0; i < TREE_VEC_LENGTH (parms); ++i)
358 tree parm = TREE_VALUE (TREE_VEC_ELT (parms, i));
359 my_friendly_assert (DECL_P (parm), 0);
361 switch (TREE_CODE (parm))
370 /* Make a CONST_DECL as is done in process_template_parm.
371 It is ugly that we recreate this here; the original
372 version built in process_template_parm is no longer
374 tree decl = build_decl (CONST_DECL, DECL_NAME (parm),
376 DECL_ARTIFICIAL (decl) = 1;
377 TREE_CONSTANT (decl) = 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 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 /* Returns nonzero iff T is a member template function. We must be
447 template <class T> class C { void f(); }
449 Here, f is a template function, and a member, but not a member
450 template. This function does not concern itself with the origin of
451 T, only its present state. So if we have
453 template <class T> class C { template <class U> void f(U); }
455 then neither C<int>::f<char> nor C<T>::f<double> is considered
456 to be a member template. But, `template <class U> void
457 C<int>::f(U)' is considered a member template. */
460 is_member_template (tree t)
462 if (!DECL_FUNCTION_TEMPLATE_P (t))
463 /* Anything that isn't a function or a template function is
464 certainly not a member template. */
467 /* A local class can't have member templates. */
468 if (decl_function_context (t))
471 return (DECL_FUNCTION_MEMBER_P (DECL_TEMPLATE_RESULT (t))
472 /* If there are more levels of template parameters than
473 there are template classes surrounding the declaration,
474 then we have a member template. */
475 && (TMPL_PARMS_DEPTH (DECL_TEMPLATE_PARMS (t)) >
476 template_class_depth (DECL_CONTEXT (t))));
480 /* Returns nonzero iff T is a member template class. See
481 is_member_template for a description of what precisely constitutes
482 a member template. */
485 is_member_template_class (tree t)
487 if (!DECL_CLASS_TEMPLATE_P (t))
488 /* Anything that isn't a class template, is certainly not a member
492 if (!DECL_CLASS_SCOPE_P (t))
493 /* Anything whose context isn't a class type is surely not a
497 /* If there are more levels of template parameters than there are
498 template classes surrounding the declaration, then we have a
500 return (TMPL_PARMS_DEPTH (DECL_TEMPLATE_PARMS (t)) >
501 template_class_depth (DECL_CONTEXT (t)));
505 /* Return a new template argument vector which contains all of ARGS,
506 but has as its innermost set of arguments the EXTRA_ARGS. */
509 add_to_template_args (tree args, tree extra_args)
516 extra_depth = TMPL_ARGS_DEPTH (extra_args);
517 new_args = make_tree_vec (TMPL_ARGS_DEPTH (args) + extra_depth);
519 for (i = 1; i <= TMPL_ARGS_DEPTH (args); ++i)
520 SET_TMPL_ARGS_LEVEL (new_args, i, TMPL_ARGS_LEVEL (args, i));
522 for (j = 1; j <= extra_depth; ++j, ++i)
523 SET_TMPL_ARGS_LEVEL (new_args, i, TMPL_ARGS_LEVEL (extra_args, j));
528 /* Like add_to_template_args, but only the outermost ARGS are added to
529 the EXTRA_ARGS. In particular, all but TMPL_ARGS_DEPTH
530 (EXTRA_ARGS) levels are added. This function is used to combine
531 the template arguments from a partial instantiation with the
532 template arguments used to attain the full instantiation from the
533 partial instantiation. */
536 add_outermost_template_args (tree args, tree extra_args)
540 /* If there are more levels of EXTRA_ARGS than there are ARGS,
541 something very fishy is going on. */
542 my_friendly_assert (TMPL_ARGS_DEPTH (args) >= TMPL_ARGS_DEPTH (extra_args),
545 /* If *all* the new arguments will be the EXTRA_ARGS, just return
547 if (TMPL_ARGS_DEPTH (args) == TMPL_ARGS_DEPTH (extra_args))
550 /* For the moment, we make ARGS look like it contains fewer levels. */
551 TREE_VEC_LENGTH (args) -= TMPL_ARGS_DEPTH (extra_args);
553 new_args = add_to_template_args (args, extra_args);
555 /* Now, we restore ARGS to its full dimensions. */
556 TREE_VEC_LENGTH (args) += TMPL_ARGS_DEPTH (extra_args);
561 /* Return the N levels of innermost template arguments from the ARGS. */
564 get_innermost_template_args (tree args, int n)
570 my_friendly_assert (n >= 0, 20000603);
572 /* If N is 1, just return the innermost set of template arguments. */
574 return TMPL_ARGS_LEVEL (args, TMPL_ARGS_DEPTH (args));
576 /* If we're not removing anything, just return the arguments we were
578 extra_levels = TMPL_ARGS_DEPTH (args) - n;
579 my_friendly_assert (extra_levels >= 0, 20000603);
580 if (extra_levels == 0)
583 /* Make a new set of arguments, not containing the outer arguments. */
584 new_args = make_tree_vec (n);
585 for (i = 1; i <= n; ++i)
586 SET_TMPL_ARGS_LEVEL (new_args, i,
587 TMPL_ARGS_LEVEL (args, i + extra_levels));
592 /* We've got a template header coming up; push to a new level for storing
596 begin_template_parm_list (void)
598 /* We use a non-tag-transparent scope here, which causes pushtag to
599 put tags in this scope, rather than in the enclosing class or
600 namespace scope. This is the right thing, since we want
601 TEMPLATE_DECLS, and not TYPE_DECLS for template classes. For a
602 global template class, push_template_decl handles putting the
603 TEMPLATE_DECL into top-level scope. For a nested template class,
606 template <class T> struct S1 {
607 template <class T> struct S2 {};
610 pushtag contains special code to call pushdecl_with_scope on the
611 TEMPLATE_DECL for S2. */
612 begin_scope (sk_template_parms);
613 ++processing_template_decl;
614 ++processing_template_parmlist;
615 note_template_header (0);
618 /* This routine is called when a specialization is declared. If it is
619 invalid to declare a specialization here, an error is reported. */
622 check_specialization_scope (void)
624 tree scope = current_scope ();
628 An explicit specialization shall be declared in the namespace of
629 which the template is a member, or, for member templates, in the
630 namespace of which the enclosing class or enclosing class
631 template is a member. An explicit specialization of a member
632 function, member class or static data member of a class template
633 shall be declared in the namespace of which the class template
635 if (scope && TREE_CODE (scope) != NAMESPACE_DECL)
636 error ("explicit specialization in non-namespace scope `%D'",
641 In an explicit specialization declaration for a member of a class
642 template or a member template that appears in namespace scope,
643 the member template and some of its enclosing class templates may
644 remain unspecialized, except that the declaration shall not
645 explicitly specialize a class member template if its enclosing
646 class templates are not explicitly specialized as well. */
647 if (current_template_parms)
648 error ("enclosing class templates are not explicitly specialized");
651 /* We've just seen template <>. */
654 begin_specialization (void)
656 begin_scope (sk_template_spec);
657 note_template_header (1);
658 check_specialization_scope ();
661 /* Called at then end of processing a declaration preceded by
665 end_specialization (void)
668 reset_specialization ();
671 /* Any template <>'s that we have seen thus far are not referring to a
672 function specialization. */
675 reset_specialization (void)
677 processing_specialization = 0;
678 template_header_count = 0;
681 /* We've just seen a template header. If SPECIALIZATION is nonzero,
682 it was of the form template <>. */
685 note_template_header (int specialization)
687 processing_specialization = specialization;
688 template_header_count++;
691 /* We're beginning an explicit instantiation. */
694 begin_explicit_instantiation (void)
696 my_friendly_assert (!processing_explicit_instantiation, 20020913);
697 processing_explicit_instantiation = true;
702 end_explicit_instantiation (void)
704 my_friendly_assert(processing_explicit_instantiation, 20020913);
705 processing_explicit_instantiation = false;
708 /* The TYPE is being declared. If it is a template type, that means it
709 is a partial specialization. Do appropriate error-checking. */
712 maybe_process_partial_specialization (tree type)
714 /* TYPE maybe an ERROR_MARK_NODE. */
715 tree context = TYPE_P (type) ? TYPE_CONTEXT (type) : NULL_TREE;
717 if (CLASS_TYPE_P (type) && CLASSTYPE_USE_TEMPLATE (type))
719 /* This is for ordinary explicit specialization and partial
720 specialization of a template class such as:
722 template <> class C<int>;
726 template <class T> class C<T*>;
728 Make sure that `C<int>' and `C<T*>' are implicit instantiations. */
730 if (CLASSTYPE_IMPLICIT_INSTANTIATION (type)
731 && !COMPLETE_TYPE_P (type))
733 if (current_namespace
734 != decl_namespace_context (CLASSTYPE_TI_TEMPLATE (type)))
736 pedwarn ("specializing `%#T' in different namespace", type);
737 cp_pedwarn_at (" from definition of `%#D'",
738 CLASSTYPE_TI_TEMPLATE (type));
740 SET_CLASSTYPE_TEMPLATE_SPECIALIZATION (type);
741 if (processing_template_decl)
742 push_template_decl (TYPE_MAIN_DECL (type));
744 else if (CLASSTYPE_TEMPLATE_INSTANTIATION (type))
745 error ("specialization of `%T' after instantiation", type);
747 else if (CLASS_TYPE_P (type)
748 && !CLASSTYPE_USE_TEMPLATE (type)
749 && CLASSTYPE_TEMPLATE_INFO (type)
750 && context && CLASS_TYPE_P (context)
751 && CLASSTYPE_TEMPLATE_INFO (context))
753 /* This is for an explicit specialization of member class
754 template according to [temp.expl.spec/18]:
756 template <> template <class U> class C<int>::D;
758 The context `C<int>' must be an implicit instantiation.
759 Otherwise this is just a member class template declared
762 template <> class C<int> { template <class U> class D; };
763 template <> template <class U> class C<int>::D;
765 In the first case, `C<int>::D' is a specialization of `C<T>::D'
766 while in the second case, `C<int>::D' is a primary template
767 and `C<T>::D' may not exist. */
769 if (CLASSTYPE_IMPLICIT_INSTANTIATION (context)
770 && !COMPLETE_TYPE_P (type))
774 if (current_namespace
775 != decl_namespace_context (CLASSTYPE_TI_TEMPLATE (type)))
777 pedwarn ("specializing `%#T' in different namespace", type);
778 cp_pedwarn_at (" from definition of `%#D'",
779 CLASSTYPE_TI_TEMPLATE (type));
782 /* Check for invalid specialization after instantiation:
784 template <> template <> class C<int>::D<int>;
785 template <> template <class U> class C<int>::D; */
787 for (t = DECL_TEMPLATE_INSTANTIATIONS
788 (most_general_template (CLASSTYPE_TI_TEMPLATE (type)));
789 t; t = TREE_CHAIN (t))
790 if (TREE_VALUE (t) != type
791 && TYPE_CONTEXT (TREE_VALUE (t)) == context)
792 error ("specialization `%T' after instantiation `%T'",
793 type, TREE_VALUE (t));
795 /* Mark TYPE as a specialization. And as a result, we only
796 have one level of template argument for the innermost
798 SET_CLASSTYPE_TEMPLATE_SPECIALIZATION (type);
799 CLASSTYPE_TI_ARGS (type)
800 = INNERMOST_TEMPLATE_ARGS (CLASSTYPE_TI_ARGS (type));
803 else if (processing_specialization)
804 error ("explicit specialization of non-template `%T'", type);
807 /* Retrieve the specialization (in the sense of [temp.spec] - a
808 specialization is either an instantiation or an explicit
809 specialization) of TMPL for the given template ARGS. If there is
810 no such specialization, return NULL_TREE. The ARGS are a vector of
811 arguments, or a vector of vectors of arguments, in the case of
812 templates with more than one level of parameters. */
815 retrieve_specialization (tree tmpl, tree args)
819 my_friendly_assert (TREE_CODE (tmpl) == TEMPLATE_DECL, 0);
821 /* There should be as many levels of arguments as there are
822 levels of parameters. */
823 my_friendly_assert (TMPL_ARGS_DEPTH (args)
824 == TMPL_PARMS_DEPTH (DECL_TEMPLATE_PARMS (tmpl)),
827 for (s = DECL_TEMPLATE_SPECIALIZATIONS (tmpl);
830 if (comp_template_args (TREE_PURPOSE (s), args))
831 return TREE_VALUE (s);
836 /* Like retrieve_specialization, but for local declarations. */
839 retrieve_local_specialization (tree tmpl)
841 tree spec = htab_find_with_hash (local_specializations, tmpl,
842 htab_hash_pointer (tmpl));
843 return spec ? TREE_PURPOSE (spec) : NULL_TREE;
846 /* Returns nonzero iff DECL is a specialization of TMPL. */
849 is_specialization_of (tree decl, tree tmpl)
853 if (TREE_CODE (decl) == FUNCTION_DECL)
857 t = DECL_TEMPLATE_INFO (t) ? DECL_TI_TEMPLATE (t) : NULL_TREE)
863 my_friendly_assert (TREE_CODE (decl) == TYPE_DECL, 0);
865 for (t = TREE_TYPE (decl);
867 t = CLASSTYPE_USE_TEMPLATE (t)
868 ? TREE_TYPE (CLASSTYPE_TI_TEMPLATE (t)) : NULL_TREE)
869 if (same_type_ignoring_top_level_qualifiers_p (t, TREE_TYPE (tmpl)))
876 /* Register the specialization SPEC as a specialization of TMPL with
877 the indicated ARGS. Returns SPEC, or an equivalent prior
878 declaration, if available. */
881 register_specialization (tree spec, tree tmpl, tree args)
885 my_friendly_assert (TREE_CODE (tmpl) == TEMPLATE_DECL, 0);
887 if (TREE_CODE (spec) == FUNCTION_DECL
888 && uses_template_parms (DECL_TI_ARGS (spec)))
889 /* This is the FUNCTION_DECL for a partial instantiation. Don't
890 register it; we want the corresponding TEMPLATE_DECL instead.
891 We use `uses_template_parms (DECL_TI_ARGS (spec))' rather than
892 the more obvious `uses_template_parms (spec)' to avoid problems
893 with default function arguments. In particular, given
896 template <class T> void f(T t1, T t = T())
898 the default argument expression is not substituted for in an
899 instantiation unless and until it is actually needed. */
902 /* There should be as many levels of arguments as there are
903 levels of parameters. */
904 my_friendly_assert (TMPL_ARGS_DEPTH (args)
905 == TMPL_PARMS_DEPTH (DECL_TEMPLATE_PARMS (tmpl)),
908 for (s = DECL_TEMPLATE_SPECIALIZATIONS (tmpl);
912 tree fn = TREE_VALUE (s);
914 /* We can sometimes try to re-register a specialization that we've
915 already got. In particular, regenerate_decl_from_template
916 calls duplicate_decls which will update the specialization
917 list. But, we'll still get called again here anyhow. It's
918 more convenient to simply allow this than to try to prevent it. */
921 else if (comp_template_args (TREE_PURPOSE (s), args))
923 if (DECL_TEMPLATE_SPECIALIZATION (spec))
925 if (DECL_TEMPLATE_INSTANTIATION (fn))
928 || DECL_EXPLICIT_INSTANTIATION (fn))
930 error ("specialization of %D after instantiation",
936 /* This situation should occur only if the first
937 specialization is an implicit instantiation,
938 the second is an explicit specialization, and
939 the implicit instantiation has not yet been
940 used. That situation can occur if we have
941 implicitly instantiated a member function and
942 then specialized it later.
944 We can also wind up here if a friend
945 declaration that looked like an instantiation
946 turns out to be a specialization:
948 template <class T> void foo(T);
949 class S { friend void foo<>(int) };
950 template <> void foo(int);
952 We transform the existing DECL in place so that
953 any pointers to it become pointers to the
956 If there was a definition for the template, but
957 not for the specialization, we want this to
958 look as if there is no definition, and vice
960 DECL_INITIAL (fn) = NULL_TREE;
961 duplicate_decls (spec, fn);
966 else if (DECL_TEMPLATE_SPECIALIZATION (fn))
968 if (!duplicate_decls (spec, fn) && DECL_INITIAL (spec))
969 /* Dup decl failed, but this is a new
970 definition. Set the line number so any errors
971 match this new definition. */
972 DECL_SOURCE_LOCATION (fn) = DECL_SOURCE_LOCATION (spec);
980 DECL_TEMPLATE_SPECIALIZATIONS (tmpl)
981 = tree_cons (args, spec, DECL_TEMPLATE_SPECIALIZATIONS (tmpl));
986 /* Unregister the specialization SPEC as a specialization of TMPL.
987 Replace it with NEW_SPEC, if NEW_SPEC is non-NULL. Returns true
988 if the SPEC was listed as a specialization of TMPL. */
991 reregister_specialization (tree spec, tree tmpl, tree new_spec)
995 for (s = &DECL_TEMPLATE_SPECIALIZATIONS (tmpl);
997 s = &TREE_CHAIN (*s))
998 if (TREE_VALUE (*s) == spec)
1001 *s = TREE_CHAIN (*s);
1003 TREE_VALUE (*s) = new_spec;
1010 /* Compare an entry in the local specializations hash table P1 (which
1011 is really a pointer to a TREE_LIST) with P2 (which is really a
1015 eq_local_specializations (const void *p1, const void *p2)
1017 return TREE_VALUE ((tree) p1) == (tree) p2;
1020 /* Hash P1, an entry in the local specializations table. */
1023 hash_local_specialization (const void* p1)
1025 return htab_hash_pointer (TREE_VALUE ((tree) p1));
1028 /* Like register_specialization, but for local declarations. We are
1029 registering SPEC, an instantiation of TMPL. */
1032 register_local_specialization (tree spec, tree tmpl)
1036 slot = htab_find_slot_with_hash (local_specializations, tmpl,
1037 htab_hash_pointer (tmpl), INSERT);
1038 *slot = build_tree_list (spec, tmpl);
1041 /* Print the list of candidate FNS in an error message. */
1044 print_candidates (tree fns)
1048 const char *str = "candidates are:";
1050 for (fn = fns; fn != NULL_TREE; fn = TREE_CHAIN (fn))
1054 for (f = TREE_VALUE (fn); f; f = OVL_NEXT (f))
1055 cp_error_at ("%s %+#D", str, OVL_CURRENT (f));
1060 /* Returns the template (one of the functions given by TEMPLATE_ID)
1061 which can be specialized to match the indicated DECL with the
1062 explicit template args given in TEMPLATE_ID. The DECL may be
1063 NULL_TREE if none is available. In that case, the functions in
1064 TEMPLATE_ID are non-members.
1066 If NEED_MEMBER_TEMPLATE is nonzero the function is known to be a
1067 specialization of a member template.
1069 The template args (those explicitly specified and those deduced)
1070 are output in a newly created vector *TARGS_OUT.
1072 If it is impossible to determine the result, an error message is
1073 issued. The error_mark_node is returned to indicate failure. */
1076 determine_specialization (tree template_id,
1079 int need_member_template)
1083 tree explicit_targs;
1084 tree candidates = NULL_TREE;
1085 tree templates = NULL_TREE;
1087 *targs_out = NULL_TREE;
1089 if (template_id == error_mark_node)
1090 return error_mark_node;
1092 fns = TREE_OPERAND (template_id, 0);
1093 explicit_targs = TREE_OPERAND (template_id, 1);
1095 if (fns == error_mark_node)
1096 return error_mark_node;
1098 /* Check for baselinks. */
1099 if (BASELINK_P (fns))
1100 fns = BASELINK_FUNCTIONS (fns);
1102 if (!is_overloaded_fn (fns))
1104 error ("`%D' is not a function template", fns);
1105 return error_mark_node;
1108 for (; fns; fns = OVL_NEXT (fns))
1110 tree fn = OVL_CURRENT (fns);
1112 if (TREE_CODE (fn) == TEMPLATE_DECL)
1114 tree decl_arg_types;
1116 /* DECL might be a specialization of FN. */
1118 /* Adjust the type of DECL in case FN is a static member. */
1119 decl_arg_types = TYPE_ARG_TYPES (TREE_TYPE (decl));
1120 if (DECL_STATIC_FUNCTION_P (fn)
1121 && DECL_NONSTATIC_MEMBER_FUNCTION_P (decl))
1122 decl_arg_types = TREE_CHAIN (decl_arg_types);
1124 /* Check that the number of function parameters matches.
1126 template <class T> void f(int i = 0);
1127 template <> void f<int>();
1128 The specialization f<int> is invalid but is not caught
1129 by get_bindings below. */
1131 if (list_length (TYPE_ARG_TYPES (TREE_TYPE (fn)))
1132 != list_length (decl_arg_types))
1135 /* See whether this function might be a specialization of this
1137 targs = get_bindings (fn, decl, explicit_targs);
1140 /* We cannot deduce template arguments that when used to
1141 specialize TMPL will produce DECL. */
1144 /* Save this template, and the arguments deduced. */
1145 templates = tree_cons (targs, fn, templates);
1147 else if (need_member_template)
1148 /* FN is an ordinary member function, and we need a
1149 specialization of a member template. */
1151 else if (TREE_CODE (fn) != FUNCTION_DECL)
1152 /* We can get IDENTIFIER_NODEs here in certain erroneous
1155 else if (!DECL_FUNCTION_MEMBER_P (fn))
1156 /* This is just an ordinary non-member function. Nothing can
1157 be a specialization of that. */
1159 else if (DECL_ARTIFICIAL (fn))
1160 /* Cannot specialize functions that are created implicitly. */
1164 tree decl_arg_types;
1166 /* This is an ordinary member function. However, since
1167 we're here, we can assume it's enclosing class is a
1168 template class. For example,
1170 template <typename T> struct S { void f(); };
1171 template <> void S<int>::f() {}
1173 Here, S<int>::f is a non-template, but S<int> is a
1174 template class. If FN has the same type as DECL, we
1175 might be in business. */
1177 if (!DECL_TEMPLATE_INFO (fn))
1178 /* Its enclosing class is an explicit specialization
1179 of a template class. This is not a candidate. */
1182 if (!same_type_p (TREE_TYPE (TREE_TYPE (decl)),
1183 TREE_TYPE (TREE_TYPE (fn))))
1184 /* The return types differ. */
1187 /* Adjust the type of DECL in case FN is a static member. */
1188 decl_arg_types = TYPE_ARG_TYPES (TREE_TYPE (decl));
1189 if (DECL_STATIC_FUNCTION_P (fn)
1190 && DECL_NONSTATIC_MEMBER_FUNCTION_P (decl))
1191 decl_arg_types = TREE_CHAIN (decl_arg_types);
1193 if (compparms (TYPE_ARG_TYPES (TREE_TYPE (fn)),
1196 candidates = tree_cons (NULL_TREE, fn, candidates);
1200 if (templates && TREE_CHAIN (templates))
1206 It is possible for a specialization with a given function
1207 signature to be instantiated from more than one function
1208 template. In such cases, explicit specification of the
1209 template arguments must be used to uniquely identify the
1210 function template specialization being specialized.
1212 Note that here, there's no suggestion that we're supposed to
1213 determine which of the candidate templates is most
1214 specialized. However, we, also have:
1218 Partial ordering of overloaded function template
1219 declarations is used in the following contexts to select
1220 the function template to which a function template
1221 specialization refers:
1223 -- when an explicit specialization refers to a function
1226 So, we do use the partial ordering rules, at least for now.
1227 This extension can only serve to make invalid programs valid,
1228 so it's safe. And, there is strong anecdotal evidence that
1229 the committee intended the partial ordering rules to apply;
1230 the EDG front-end has that behavior, and John Spicer claims
1231 that the committee simply forgot to delete the wording in
1232 [temp.expl.spec]. */
1233 tree tmpl = most_specialized (templates, decl, explicit_targs);
1234 if (tmpl && tmpl != error_mark_node)
1236 targs = get_bindings (tmpl, decl, explicit_targs);
1237 templates = tree_cons (targs, tmpl, NULL_TREE);
1241 if (templates == NULL_TREE && candidates == NULL_TREE)
1243 cp_error_at ("template-id `%D' for `%+D' does not match any template declaration",
1245 return error_mark_node;
1247 else if ((templates && TREE_CHAIN (templates))
1248 || (candidates && TREE_CHAIN (candidates))
1249 || (templates && candidates))
1251 cp_error_at ("ambiguous template specialization `%D' for `%+D'",
1253 chainon (candidates, templates);
1254 print_candidates (candidates);
1255 return error_mark_node;
1258 /* We have one, and exactly one, match. */
1261 /* It was a specialization of an ordinary member function in a
1263 *targs_out = copy_node (DECL_TI_ARGS (TREE_VALUE (candidates)));
1264 return DECL_TI_TEMPLATE (TREE_VALUE (candidates));
1267 /* It was a specialization of a template. */
1268 targs = DECL_TI_ARGS (DECL_TEMPLATE_RESULT (TREE_VALUE (templates)));
1269 if (TMPL_ARGS_HAVE_MULTIPLE_LEVELS (targs))
1271 *targs_out = copy_node (targs);
1272 SET_TMPL_ARGS_LEVEL (*targs_out,
1273 TMPL_ARGS_DEPTH (*targs_out),
1274 TREE_PURPOSE (templates));
1277 *targs_out = TREE_PURPOSE (templates);
1278 return TREE_VALUE (templates);
1281 /* Returns a chain of parameter types, exactly like the SPEC_TYPES,
1282 but with the default argument values filled in from those in the
1286 copy_default_args_to_explicit_spec_1 (tree spec_types,
1289 tree new_spec_types;
1294 if (spec_types == void_list_node)
1295 return void_list_node;
1297 /* Substitute into the rest of the list. */
1299 copy_default_args_to_explicit_spec_1 (TREE_CHAIN (spec_types),
1300 TREE_CHAIN (tmpl_types));
1302 /* Add the default argument for this parameter. */
1303 return hash_tree_cons (TREE_PURPOSE (tmpl_types),
1304 TREE_VALUE (spec_types),
1308 /* DECL is an explicit specialization. Replicate default arguments
1309 from the template it specializes. (That way, code like:
1311 template <class T> void f(T = 3);
1312 template <> void f(double);
1315 works, as required.) An alternative approach would be to look up
1316 the correct default arguments at the call-site, but this approach
1317 is consistent with how implicit instantiations are handled. */
1320 copy_default_args_to_explicit_spec (tree decl)
1325 tree new_spec_types;
1329 tree object_type = NULL_TREE;
1330 tree in_charge = NULL_TREE;
1331 tree vtt = NULL_TREE;
1333 /* See if there's anything we need to do. */
1334 tmpl = DECL_TI_TEMPLATE (decl);
1335 tmpl_types = TYPE_ARG_TYPES (TREE_TYPE (DECL_TEMPLATE_RESULT (tmpl)));
1336 for (t = tmpl_types; t; t = TREE_CHAIN (t))
1337 if (TREE_PURPOSE (t))
1342 old_type = TREE_TYPE (decl);
1343 spec_types = TYPE_ARG_TYPES (old_type);
1345 if (DECL_NONSTATIC_MEMBER_FUNCTION_P (decl))
1347 /* Remove the this pointer, but remember the object's type for
1349 object_type = TREE_TYPE (TREE_VALUE (spec_types));
1350 spec_types = TREE_CHAIN (spec_types);
1351 tmpl_types = TREE_CHAIN (tmpl_types);
1353 if (DECL_HAS_IN_CHARGE_PARM_P (decl))
1355 /* DECL may contain more parameters than TMPL due to the extra
1356 in-charge parameter in constructors and destructors. */
1357 in_charge = spec_types;
1358 spec_types = TREE_CHAIN (spec_types);
1360 if (DECL_HAS_VTT_PARM_P (decl))
1363 spec_types = TREE_CHAIN (spec_types);
1367 /* Compute the merged default arguments. */
1369 copy_default_args_to_explicit_spec_1 (spec_types, tmpl_types);
1371 /* Compute the new FUNCTION_TYPE. */
1375 new_spec_types = hash_tree_cons (TREE_PURPOSE (vtt),
1380 /* Put the in-charge parameter back. */
1381 new_spec_types = hash_tree_cons (TREE_PURPOSE (in_charge),
1382 TREE_VALUE (in_charge),
1385 new_type = build_method_type_directly (object_type,
1386 TREE_TYPE (old_type),
1390 new_type = build_function_type (TREE_TYPE (old_type),
1392 new_type = build_type_attribute_variant (new_type,
1393 TYPE_ATTRIBUTES (old_type));
1394 new_type = build_exception_variant (new_type,
1395 TYPE_RAISES_EXCEPTIONS (old_type));
1396 TREE_TYPE (decl) = new_type;
1399 /* Check to see if the function just declared, as indicated in
1400 DECLARATOR, and in DECL, is a specialization of a function
1401 template. We may also discover that the declaration is an explicit
1402 instantiation at this point.
1404 Returns DECL, or an equivalent declaration that should be used
1405 instead if all goes well. Issues an error message if something is
1406 amiss. Returns error_mark_node if the error is not easily
1409 FLAGS is a bitmask consisting of the following flags:
1411 2: The function has a definition.
1412 4: The function is a friend.
1414 The TEMPLATE_COUNT is the number of references to qualifying
1415 template classes that appeared in the name of the function. For
1418 template <class T> struct S { void f(); };
1421 the TEMPLATE_COUNT would be 1. However, explicitly specialized
1422 classes are not counted in the TEMPLATE_COUNT, so that in
1424 template <class T> struct S {};
1425 template <> struct S<int> { void f(); }
1426 template <> void S<int>::f();
1428 the TEMPLATE_COUNT would be 0. (Note that this declaration is
1429 invalid; there should be no template <>.)
1431 If the function is a specialization, it is marked as such via
1432 DECL_TEMPLATE_SPECIALIZATION. Furthermore, its DECL_TEMPLATE_INFO
1433 is set up correctly, and it is added to the list of specializations
1434 for that template. */
1437 check_explicit_specialization (tree declarator,
1442 int have_def = flags & 2;
1443 int is_friend = flags & 4;
1444 int specialization = 0;
1445 int explicit_instantiation = 0;
1446 int member_specialization = 0;
1447 tree ctype = DECL_CLASS_CONTEXT (decl);
1448 tree dname = DECL_NAME (decl);
1451 tsk = current_tmpl_spec_kind (template_count);
1456 if (processing_specialization)
1459 SET_DECL_TEMPLATE_SPECIALIZATION (decl);
1461 else if (TREE_CODE (declarator) == TEMPLATE_ID_EXPR)
1464 /* This could be something like:
1466 template <class T> void f(T);
1467 class S { friend void f<>(int); } */
1471 /* This case handles bogus declarations like template <>
1472 template <class T> void f<int>(); */
1474 error ("template-id `%D' in declaration of primary template",
1481 case tsk_invalid_member_spec:
1482 /* The error has already been reported in
1483 check_specialization_scope. */
1484 return error_mark_node;
1486 case tsk_invalid_expl_inst:
1487 error ("template parameter list used in explicit instantiation");
1493 error ("definition provided for explicit instantiation");
1495 explicit_instantiation = 1;
1498 case tsk_excessive_parms:
1499 error ("too many template parameter lists in declaration of `%D'",
1501 return error_mark_node;
1505 SET_DECL_TEMPLATE_SPECIALIZATION (decl);
1507 member_specialization = 1;
1512 case tsk_insufficient_parms:
1513 if (template_header_count)
1515 error("too few template parameter lists in declaration of `%D'",
1519 else if (ctype != NULL_TREE
1520 && !TYPE_BEING_DEFINED (ctype)
1521 && CLASSTYPE_TEMPLATE_INSTANTIATION (ctype)
1524 /* For backwards compatibility, we accept:
1526 template <class T> struct S { void f(); };
1527 void S<int>::f() {} // Missing template <>
1529 That used to be valid C++. */
1532 ("explicit specialization not preceded by `template <>'");
1534 SET_DECL_TEMPLATE_SPECIALIZATION (decl);
1539 if (TREE_CODE (declarator) == TEMPLATE_ID_EXPR)
1541 /* This case handles bogus declarations like template <>
1542 template <class T> void f<int>(); */
1544 if (uses_template_parms (declarator))
1545 error ("partial specialization `%D' of function template",
1548 error ("template-id `%D' in declaration of primary template",
1553 if (ctype && CLASSTYPE_TEMPLATE_INSTANTIATION (ctype))
1554 /* This is a specialization of a member template, without
1555 specialization the containing class. Something like:
1557 template <class T> struct S {
1558 template <class U> void f (U);
1560 template <> template <class U> void S<int>::f(U) {}
1562 That's a specialization -- but of the entire template. */
1570 if (specialization || member_specialization)
1572 tree t = TYPE_ARG_TYPES (TREE_TYPE (decl));
1573 for (; t; t = TREE_CHAIN (t))
1574 if (TREE_PURPOSE (t))
1577 ("default argument specified in explicit specialization");
1580 if (current_lang_name == lang_name_c)
1581 error ("template specialization with C linkage");
1584 if (specialization || member_specialization || explicit_instantiation)
1586 tree tmpl = NULL_TREE;
1587 tree targs = NULL_TREE;
1589 /* Make sure that the declarator is a TEMPLATE_ID_EXPR. */
1590 if (TREE_CODE (declarator) != TEMPLATE_ID_EXPR)
1594 my_friendly_assert (TREE_CODE (declarator) == IDENTIFIER_NODE, 0);
1599 /* If there is no class context, the explicit instantiation
1600 must be at namespace scope. */
1601 my_friendly_assert (DECL_NAMESPACE_SCOPE_P (decl), 20030625);
1603 /* Find the namespace binding, using the declaration
1605 fns = namespace_binding (dname, CP_DECL_CONTEXT (decl));
1608 declarator = lookup_template_function (fns, NULL_TREE);
1611 if (declarator == error_mark_node)
1612 return error_mark_node;
1614 if (ctype != NULL_TREE && TYPE_BEING_DEFINED (ctype))
1616 if (!explicit_instantiation)
1617 /* A specialization in class scope. This is invalid,
1618 but the error will already have been flagged by
1619 check_specialization_scope. */
1620 return error_mark_node;
1623 /* It's not valid to write an explicit instantiation in
1626 class C { template void f(); }
1628 This case is caught by the parser. However, on
1631 template class C { void f(); };
1633 (which is invalid) we can get here. The error will be
1640 else if (ctype != NULL_TREE
1641 && (TREE_CODE (TREE_OPERAND (declarator, 0)) ==
1644 /* Find the list of functions in ctype that have the same
1645 name as the declared function. */
1646 tree name = TREE_OPERAND (declarator, 0);
1647 tree fns = NULL_TREE;
1650 if (constructor_name_p (name, ctype))
1652 int is_constructor = DECL_CONSTRUCTOR_P (decl);
1654 if (is_constructor ? !TYPE_HAS_CONSTRUCTOR (ctype)
1655 : !TYPE_HAS_DESTRUCTOR (ctype))
1657 /* From [temp.expl.spec]:
1659 If such an explicit specialization for the member
1660 of a class template names an implicitly-declared
1661 special member function (clause _special_), the
1662 program is ill-formed.
1664 Similar language is found in [temp.explicit]. */
1665 error ("specialization of implicitly-declared special member function");
1666 return error_mark_node;
1669 name = is_constructor ? ctor_identifier : dtor_identifier;
1672 if (!DECL_CONV_FN_P (decl))
1674 idx = lookup_fnfields_1 (ctype, name);
1676 fns = TREE_VEC_ELT (CLASSTYPE_METHOD_VEC (ctype), idx);
1682 /* For a type-conversion operator, we cannot do a
1683 name-based lookup. We might be looking for `operator
1684 int' which will be a specialization of `operator T'.
1685 So, we find *all* the conversion operators, and then
1686 select from them. */
1689 methods = CLASSTYPE_METHOD_VEC (ctype);
1691 for (idx = CLASSTYPE_FIRST_CONVERSION_SLOT;
1692 idx < TREE_VEC_LENGTH (methods); ++idx)
1694 tree ovl = TREE_VEC_ELT (methods, idx);
1696 if (!ovl || !DECL_CONV_FN_P (OVL_CURRENT (ovl)))
1697 /* There are no more conversion functions. */
1700 /* Glue all these conversion functions together
1701 with those we already have. */
1702 for (; ovl; ovl = OVL_NEXT (ovl))
1703 fns = ovl_cons (OVL_CURRENT (ovl), fns);
1707 if (fns == NULL_TREE)
1709 error ("no member function `%D' declared in `%T'",
1711 return error_mark_node;
1714 TREE_OPERAND (declarator, 0) = fns;
1717 /* Figure out what exactly is being specialized at this point.
1718 Note that for an explicit instantiation, even one for a
1719 member function, we cannot tell apriori whether the
1720 instantiation is for a member template, or just a member
1721 function of a template class. Even if a member template is
1722 being instantiated, the member template arguments may be
1723 elided if they can be deduced from the rest of the
1725 tmpl = determine_specialization (declarator, decl,
1727 member_specialization);
1729 if (!tmpl || tmpl == error_mark_node)
1730 /* We couldn't figure out what this declaration was
1732 return error_mark_node;
1735 tree gen_tmpl = most_general_template (tmpl);
1737 if (explicit_instantiation)
1739 /* We don't set DECL_EXPLICIT_INSTANTIATION here; that
1740 is done by do_decl_instantiation later. */
1742 int arg_depth = TMPL_ARGS_DEPTH (targs);
1743 int parm_depth = TMPL_PARMS_DEPTH (DECL_TEMPLATE_PARMS (tmpl));
1745 if (arg_depth > parm_depth)
1747 /* If TMPL is not the most general template (for
1748 example, if TMPL is a friend template that is
1749 injected into namespace scope), then there will
1750 be too many levels of TARGS. Remove some of them
1755 new_targs = make_tree_vec (parm_depth);
1756 for (i = arg_depth - parm_depth; i < arg_depth; ++i)
1757 TREE_VEC_ELT (new_targs, i - (arg_depth - parm_depth))
1758 = TREE_VEC_ELT (targs, i);
1762 return instantiate_template (tmpl, targs, tf_error);
1765 /* If we thought that the DECL was a member function, but it
1766 turns out to be specializing a static member function,
1767 make DECL a static member function as well. We also have
1768 to adjust last_function_parms to avoid confusing
1769 start_function later. */
1770 if (DECL_STATIC_FUNCTION_P (tmpl)
1771 && DECL_NONSTATIC_MEMBER_FUNCTION_P (decl))
1773 revert_static_member_fn (decl);
1774 last_function_parms = TREE_CHAIN (last_function_parms);
1777 /* If this is a specialization of a member template of a
1778 template class. In we want to return the TEMPLATE_DECL,
1779 not the specialization of it. */
1780 if (tsk == tsk_template)
1782 SET_DECL_TEMPLATE_SPECIALIZATION (tmpl);
1783 DECL_INITIAL (DECL_TEMPLATE_RESULT (tmpl)) = NULL_TREE;
1786 DECL_SOURCE_LOCATION (tmpl) = DECL_SOURCE_LOCATION (decl);
1787 DECL_SOURCE_LOCATION (DECL_TEMPLATE_RESULT (tmpl))
1788 = DECL_SOURCE_LOCATION (decl);
1793 /* Set up the DECL_TEMPLATE_INFO for DECL. */
1794 DECL_TEMPLATE_INFO (decl) = tree_cons (tmpl, targs, NULL_TREE);
1796 /* Inherit default function arguments from the template
1797 DECL is specializing. */
1798 copy_default_args_to_explicit_spec (decl);
1800 /* This specialization has the same protection as the
1801 template it specializes. */
1802 TREE_PRIVATE (decl) = TREE_PRIVATE (gen_tmpl);
1803 TREE_PROTECTED (decl) = TREE_PROTECTED (gen_tmpl);
1805 if (is_friend && !have_def)
1806 /* This is not really a declaration of a specialization.
1807 It's just the name of an instantiation. But, it's not
1808 a request for an instantiation, either. */
1809 SET_DECL_IMPLICIT_INSTANTIATION (decl);
1810 else if (DECL_CONSTRUCTOR_P (decl) || DECL_DESTRUCTOR_P (decl))
1811 /* This is indeed a specialization. In case of constructors
1812 and destructors, we need in-charge and not-in-charge
1813 versions in V3 ABI. */
1814 clone_function_decl (decl, /*update_method_vec_p=*/0);
1816 /* Register this specialization so that we can find it
1818 decl = register_specialization (decl, gen_tmpl, targs);
1825 /* TYPE is being declared. Verify that the use of template headers
1826 and such is reasonable. Issue error messages if not. */
1829 maybe_check_template_type (tree type)
1831 if (template_header_count)
1833 /* We are in the scope of some `template <...>' header. */
1836 = template_class_depth_real (TYPE_CONTEXT (type),
1837 /*count_specializations=*/1);
1839 if (template_header_count <= context_depth)
1840 /* This is OK; the template headers are for the context. We
1841 are actually too lenient here; like
1842 check_explicit_specialization we should consider the number
1843 of template types included in the actual declaration. For
1846 template <class T> struct S {
1847 template <class U> template <class V>
1853 template <class T> struct S {
1854 template <class U> struct I;
1857 template <class T> template <class U.
1862 else if (template_header_count > context_depth + 1)
1863 /* There are two many template parameter lists. */
1864 error ("too many template parameter lists in declaration of `%T'", type);
1868 /* Returns 1 iff PARMS1 and PARMS2 are identical sets of template
1869 parameters. These are represented in the same format used for
1870 DECL_TEMPLATE_PARMS. */
1872 int comp_template_parms (tree parms1, tree parms2)
1877 if (parms1 == parms2)
1880 for (p1 = parms1, p2 = parms2;
1881 p1 != NULL_TREE && p2 != NULL_TREE;
1882 p1 = TREE_CHAIN (p1), p2 = TREE_CHAIN (p2))
1884 tree t1 = TREE_VALUE (p1);
1885 tree t2 = TREE_VALUE (p2);
1888 my_friendly_assert (TREE_CODE (t1) == TREE_VEC, 0);
1889 my_friendly_assert (TREE_CODE (t2) == TREE_VEC, 0);
1891 if (TREE_VEC_LENGTH (t1) != TREE_VEC_LENGTH (t2))
1894 for (i = 0; i < TREE_VEC_LENGTH (t2); ++i)
1896 tree parm1 = TREE_VALUE (TREE_VEC_ELT (t1, i));
1897 tree parm2 = TREE_VALUE (TREE_VEC_ELT (t2, i));
1899 if (TREE_CODE (parm1) != TREE_CODE (parm2))
1902 if (TREE_CODE (parm1) == TEMPLATE_TYPE_PARM)
1904 else if (!same_type_p (TREE_TYPE (parm1), TREE_TYPE (parm2)))
1909 if ((p1 != NULL_TREE) != (p2 != NULL_TREE))
1910 /* One set of parameters has more parameters lists than the
1917 /* Complain if DECL shadows a template parameter.
1919 [temp.local]: A template-parameter shall not be redeclared within its
1920 scope (including nested scopes). */
1923 check_template_shadow (tree decl)
1927 /* If we're not in a template, we can't possibly shadow a template
1929 if (!current_template_parms)
1932 /* Figure out what we're shadowing. */
1933 if (TREE_CODE (decl) == OVERLOAD)
1934 decl = OVL_CURRENT (decl);
1935 olddecl = IDENTIFIER_VALUE (DECL_NAME (decl));
1937 /* If there's no previous binding for this name, we're not shadowing
1938 anything, let alone a template parameter. */
1942 /* If we're not shadowing a template parameter, we're done. Note
1943 that OLDDECL might be an OVERLOAD (or perhaps even an
1944 ERROR_MARK), so we can't just blithely assume it to be a _DECL
1946 if (!DECL_P (olddecl) || !DECL_TEMPLATE_PARM_P (olddecl))
1949 /* We check for decl != olddecl to avoid bogus errors for using a
1950 name inside a class. We check TPFI to avoid duplicate errors for
1951 inline member templates. */
1953 || TEMPLATE_PARMS_FOR_INLINE (current_template_parms))
1956 cp_error_at ("declaration of `%#D'", decl);
1957 cp_error_at (" shadows template parm `%#D'", olddecl);
1960 /* Return a new TEMPLATE_PARM_INDEX with the indicated INDEX, LEVEL,
1961 ORIG_LEVEL, DECL, and TYPE. */
1964 build_template_parm_index (int index,
1970 tree t = make_node (TEMPLATE_PARM_INDEX);
1971 TEMPLATE_PARM_IDX (t) = index;
1972 TEMPLATE_PARM_LEVEL (t) = level;
1973 TEMPLATE_PARM_ORIG_LEVEL (t) = orig_level;
1974 TEMPLATE_PARM_DECL (t) = decl;
1975 TREE_TYPE (t) = type;
1976 TREE_CONSTANT (t) = TREE_CONSTANT (decl);
1977 TREE_READONLY (t) = TREE_READONLY (decl);
1982 /* Return a TEMPLATE_PARM_INDEX, similar to INDEX, but whose
1983 TEMPLATE_PARM_LEVEL has been decreased by LEVELS. If such a
1984 TEMPLATE_PARM_INDEX already exists, it is returned; otherwise, a
1985 new one is created. */
1988 reduce_template_parm_level (tree index, tree type, int levels)
1990 if (TEMPLATE_PARM_DESCENDANTS (index) == NULL_TREE
1991 || (TEMPLATE_PARM_LEVEL (TEMPLATE_PARM_DESCENDANTS (index))
1992 != TEMPLATE_PARM_LEVEL (index) - levels))
1994 tree orig_decl = TEMPLATE_PARM_DECL (index);
1997 decl = build_decl (TREE_CODE (orig_decl), DECL_NAME (orig_decl), type);
1998 TREE_CONSTANT (decl) = TREE_CONSTANT (orig_decl);
1999 TREE_READONLY (decl) = TREE_READONLY (orig_decl);
2000 DECL_ARTIFICIAL (decl) = 1;
2001 SET_DECL_TEMPLATE_PARM_P (decl);
2003 t = build_template_parm_index (TEMPLATE_PARM_IDX (index),
2004 TEMPLATE_PARM_LEVEL (index) - levels,
2005 TEMPLATE_PARM_ORIG_LEVEL (index),
2007 TEMPLATE_PARM_DESCENDANTS (index) = t;
2009 /* Template template parameters need this. */
2010 DECL_TEMPLATE_PARMS (decl)
2011 = DECL_TEMPLATE_PARMS (TEMPLATE_PARM_DECL (index));
2014 return TEMPLATE_PARM_DESCENDANTS (index);
2017 /* Process information from new template parameter NEXT and append it to the
2018 LIST being built. */
2021 process_template_parm (tree list, tree next)
2029 my_friendly_assert (TREE_CODE (parm) == TREE_LIST, 259);
2030 defval = TREE_PURPOSE (parm);
2031 parm = TREE_VALUE (parm);
2032 is_type = TREE_PURPOSE (parm) == class_type_node;
2036 tree p = TREE_VALUE (tree_last (list));
2038 if (TREE_CODE (p) == TYPE_DECL || TREE_CODE (p) == TEMPLATE_DECL)
2039 idx = TEMPLATE_TYPE_IDX (TREE_TYPE (p));
2041 idx = TEMPLATE_PARM_IDX (DECL_INITIAL (p));
2049 my_friendly_assert (TREE_CODE (TREE_PURPOSE (parm)) == TREE_LIST, 260);
2050 /* is a const-param */
2051 parm = grokdeclarator (TREE_VALUE (parm), TREE_PURPOSE (parm),
2053 SET_DECL_TEMPLATE_PARM_P (parm);
2057 The top-level cv-qualifiers on the template-parameter are
2058 ignored when determining its type. */
2059 TREE_TYPE (parm) = TYPE_MAIN_VARIANT (TREE_TYPE (parm));
2061 /* A template parameter is not modifiable. */
2062 TREE_READONLY (parm) = TREE_CONSTANT (parm) = 1;
2063 if (invalid_nontype_parm_type_p (TREE_TYPE (parm), 1))
2064 TREE_TYPE (parm) = void_type_node;
2065 decl = build_decl (CONST_DECL, DECL_NAME (parm), TREE_TYPE (parm));
2066 TREE_CONSTANT (decl) = TREE_READONLY (decl) = 1;
2067 DECL_INITIAL (parm) = DECL_INITIAL (decl)
2068 = build_template_parm_index (idx, processing_template_decl,
2069 processing_template_decl,
2070 decl, TREE_TYPE (parm));
2075 parm = TREE_VALUE (parm);
2077 if (parm && TREE_CODE (parm) == TEMPLATE_DECL)
2079 t = make_aggr_type (TEMPLATE_TEMPLATE_PARM);
2080 /* This is for distinguishing between real templates and template
2081 template parameters */
2082 TREE_TYPE (parm) = t;
2083 TREE_TYPE (DECL_TEMPLATE_RESULT (parm)) = t;
2088 t = make_aggr_type (TEMPLATE_TYPE_PARM);
2089 /* parm is either IDENTIFIER_NODE or NULL_TREE */
2090 decl = build_decl (TYPE_DECL, parm, t);
2093 TYPE_NAME (t) = decl;
2094 TYPE_STUB_DECL (t) = decl;
2096 TEMPLATE_TYPE_PARM_INDEX (t)
2097 = build_template_parm_index (idx, processing_template_decl,
2098 processing_template_decl,
2099 decl, TREE_TYPE (parm));
2101 DECL_ARTIFICIAL (decl) = 1;
2102 SET_DECL_TEMPLATE_PARM_P (decl);
2104 parm = build_tree_list (defval, parm);
2105 return chainon (list, parm);
2108 /* The end of a template parameter list has been reached. Process the
2109 tree list into a parameter vector, converting each parameter into a more
2110 useful form. Type parameters are saved as IDENTIFIER_NODEs, and others
2114 end_template_parm_list (tree parms)
2118 tree saved_parmlist = make_tree_vec (list_length (parms));
2120 current_template_parms
2121 = tree_cons (size_int (processing_template_decl),
2122 saved_parmlist, current_template_parms);
2124 for (parm = parms, nparms = 0; parm; parm = next, nparms++)
2126 next = TREE_CHAIN (parm);
2127 TREE_VEC_ELT (saved_parmlist, nparms) = parm;
2128 TREE_CHAIN (parm) = NULL_TREE;
2131 --processing_template_parmlist;
2133 return saved_parmlist;
2136 /* end_template_decl is called after a template declaration is seen. */
2139 end_template_decl (void)
2141 reset_specialization ();
2143 if (! processing_template_decl)
2146 /* This matches the pushlevel in begin_template_parm_list. */
2149 --processing_template_decl;
2150 current_template_parms = TREE_CHAIN (current_template_parms);
2153 /* Given a template argument vector containing the template PARMS.
2154 The innermost PARMS are given first. */
2157 current_template_args (void)
2160 tree args = NULL_TREE;
2161 int length = TMPL_PARMS_DEPTH (current_template_parms);
2164 /* If there is only one level of template parameters, we do not
2165 create a TREE_VEC of TREE_VECs. Instead, we return a single
2166 TREE_VEC containing the arguments. */
2168 args = make_tree_vec (length);
2170 for (header = current_template_parms; header; header = TREE_CHAIN (header))
2172 tree a = copy_node (TREE_VALUE (header));
2175 TREE_TYPE (a) = NULL_TREE;
2176 for (i = TREE_VEC_LENGTH (a) - 1; i >= 0; --i)
2178 tree t = TREE_VEC_ELT (a, i);
2180 /* T will be a list if we are called from within a
2181 begin/end_template_parm_list pair, but a vector directly
2182 if within a begin/end_member_template_processing pair. */
2183 if (TREE_CODE (t) == TREE_LIST)
2187 if (TREE_CODE (t) == TYPE_DECL
2188 || TREE_CODE (t) == TEMPLATE_DECL)
2191 t = DECL_INITIAL (t);
2192 TREE_VEC_ELT (a, i) = t;
2197 TREE_VEC_ELT (args, --l) = a;
2205 /* Return a TEMPLATE_DECL corresponding to DECL, using the indicated
2206 template PARMS. Used by push_template_decl below. */
2209 build_template_decl (tree decl, tree parms)
2211 tree tmpl = build_lang_decl (TEMPLATE_DECL, DECL_NAME (decl), NULL_TREE);
2212 DECL_TEMPLATE_PARMS (tmpl) = parms;
2213 DECL_CONTEXT (tmpl) = DECL_CONTEXT (decl);
2214 if (DECL_LANG_SPECIFIC (decl))
2216 DECL_STATIC_FUNCTION_P (tmpl) = DECL_STATIC_FUNCTION_P (decl);
2217 DECL_CONSTRUCTOR_P (tmpl) = DECL_CONSTRUCTOR_P (decl);
2218 DECL_DESTRUCTOR_P (tmpl) = DECL_DESTRUCTOR_P (decl);
2219 DECL_NONCONVERTING_P (tmpl) = DECL_NONCONVERTING_P (decl);
2220 DECL_ASSIGNMENT_OPERATOR_P (tmpl) = DECL_ASSIGNMENT_OPERATOR_P (decl);
2221 if (DECL_OVERLOADED_OPERATOR_P (decl))
2222 SET_OVERLOADED_OPERATOR_CODE (tmpl,
2223 DECL_OVERLOADED_OPERATOR_P (decl));
2229 struct template_parm_data
2231 /* The level of the template parameters we are currently
2235 /* The index of the specialization argument we are currently
2239 /* An array whose size is the number of template parameters. The
2240 elements are nonzero if the parameter has been used in any one
2241 of the arguments processed so far. */
2244 /* An array whose size is the number of template arguments. The
2245 elements are nonzero if the argument makes use of template
2246 parameters of this level. */
2247 int* arg_uses_template_parms;
2250 /* Subroutine of push_template_decl used to see if each template
2251 parameter in a partial specialization is used in the explicit
2252 argument list. If T is of the LEVEL given in DATA (which is
2253 treated as a template_parm_data*), then DATA->PARMS is marked
2257 mark_template_parm (tree t, void* data)
2261 struct template_parm_data* tpd = (struct template_parm_data*) data;
2263 if (TREE_CODE (t) == TEMPLATE_PARM_INDEX)
2265 level = TEMPLATE_PARM_LEVEL (t);
2266 idx = TEMPLATE_PARM_IDX (t);
2270 level = TEMPLATE_TYPE_LEVEL (t);
2271 idx = TEMPLATE_TYPE_IDX (t);
2274 if (level == tpd->level)
2276 tpd->parms[idx] = 1;
2277 tpd->arg_uses_template_parms[tpd->current_arg] = 1;
2280 /* Return zero so that for_each_template_parm will continue the
2281 traversal of the tree; we want to mark *every* template parm. */
2285 /* Process the partial specialization DECL. */
2288 process_partial_specialization (tree decl)
2290 tree type = TREE_TYPE (decl);
2291 tree maintmpl = CLASSTYPE_TI_TEMPLATE (type);
2292 tree specargs = CLASSTYPE_TI_ARGS (type);
2293 tree inner_args = INNERMOST_TEMPLATE_ARGS (specargs);
2294 tree inner_parms = INNERMOST_TEMPLATE_PARMS (current_template_parms);
2295 tree main_inner_parms = DECL_INNERMOST_TEMPLATE_PARMS (maintmpl);
2296 int nargs = TREE_VEC_LENGTH (inner_args);
2297 int ntparms = TREE_VEC_LENGTH (inner_parms);
2299 int did_error_intro = 0;
2300 struct template_parm_data tpd;
2301 struct template_parm_data tpd2;
2303 /* We check that each of the template parameters given in the
2304 partial specialization is used in the argument list to the
2305 specialization. For example:
2307 template <class T> struct S;
2308 template <class T> struct S<T*>;
2310 The second declaration is OK because `T*' uses the template
2311 parameter T, whereas
2313 template <class T> struct S<int>;
2315 is no good. Even trickier is:
2326 The S2<T> declaration is actually invalid; it is a
2327 full-specialization. Of course,
2330 struct S2<T (*)(U)>;
2332 or some such would have been OK. */
2333 tpd.level = TMPL_PARMS_DEPTH (current_template_parms);
2334 tpd.parms = alloca (sizeof (int) * ntparms);
2335 memset (tpd.parms, 0, sizeof (int) * ntparms);
2337 tpd.arg_uses_template_parms = alloca (sizeof (int) * nargs);
2338 memset (tpd.arg_uses_template_parms, 0, sizeof (int) * nargs);
2339 for (i = 0; i < nargs; ++i)
2341 tpd.current_arg = i;
2342 for_each_template_parm (TREE_VEC_ELT (inner_args, i),
2343 &mark_template_parm,
2347 for (i = 0; i < ntparms; ++i)
2348 if (tpd.parms[i] == 0)
2350 /* One of the template parms was not used in the
2352 if (!did_error_intro)
2354 error ("template parameters not used in partial specialization:");
2355 did_error_intro = 1;
2359 TREE_VALUE (TREE_VEC_ELT (inner_parms, i)));
2362 /* [temp.class.spec]
2364 The argument list of the specialization shall not be identical to
2365 the implicit argument list of the primary template. */
2366 if (comp_template_args
2368 INNERMOST_TEMPLATE_ARGS (CLASSTYPE_TI_ARGS (TREE_TYPE
2370 error ("partial specialization `%T' does not specialize any template arguments", type);
2372 /* [temp.class.spec]
2374 A partially specialized non-type argument expression shall not
2375 involve template parameters of the partial specialization except
2376 when the argument expression is a simple identifier.
2378 The type of a template parameter corresponding to a specialized
2379 non-type argument shall not be dependent on a parameter of the
2381 my_friendly_assert (nargs == DECL_NTPARMS (maintmpl), 0);
2383 for (i = 0; i < nargs; ++i)
2385 tree arg = TREE_VEC_ELT (inner_args, i);
2386 if (/* These first two lines are the `non-type' bit. */
2388 && TREE_CODE (arg) != TEMPLATE_DECL
2389 /* This next line is the `argument expression is not just a
2390 simple identifier' condition and also the `specialized
2391 non-type argument' bit. */
2392 && TREE_CODE (arg) != TEMPLATE_PARM_INDEX)
2394 if (tpd.arg_uses_template_parms[i])
2395 error ("template argument `%E' involves template parameter(s)", arg);
2398 /* Look at the corresponding template parameter,
2399 marking which template parameters its type depends
2402 TREE_TYPE (TREE_VALUE (TREE_VEC_ELT (main_inner_parms,
2407 /* We haven't yet initialized TPD2. Do so now. */
2408 tpd2.arg_uses_template_parms
2409 = alloca (sizeof (int) * nargs);
2410 /* The number of parameters here is the number in the
2411 main template, which, as checked in the assertion
2413 tpd2.parms = alloca (sizeof (int) * nargs);
2415 TMPL_PARMS_DEPTH (DECL_TEMPLATE_PARMS (maintmpl));
2418 /* Mark the template parameters. But this time, we're
2419 looking for the template parameters of the main
2420 template, not in the specialization. */
2421 tpd2.current_arg = i;
2422 tpd2.arg_uses_template_parms[i] = 0;
2423 memset (tpd2.parms, 0, sizeof (int) * nargs);
2424 for_each_template_parm (type,
2425 &mark_template_parm,
2429 if (tpd2.arg_uses_template_parms [i])
2431 /* The type depended on some template parameters.
2432 If they are fully specialized in the
2433 specialization, that's OK. */
2435 for (j = 0; j < nargs; ++j)
2436 if (tpd2.parms[j] != 0
2437 && tpd.arg_uses_template_parms [j])
2439 error ("type `%T' of template argument `%E' depends on template parameter(s)",
2449 if (retrieve_specialization (maintmpl, specargs))
2450 /* We've already got this specialization. */
2453 DECL_TEMPLATE_SPECIALIZATIONS (maintmpl)
2454 = tree_cons (inner_args, inner_parms,
2455 DECL_TEMPLATE_SPECIALIZATIONS (maintmpl));
2456 TREE_TYPE (DECL_TEMPLATE_SPECIALIZATIONS (maintmpl)) = type;
2460 /* Check that a template declaration's use of default arguments is not
2461 invalid. Here, PARMS are the template parameters. IS_PRIMARY is
2462 nonzero if DECL is the thing declared by a primary template.
2463 IS_PARTIAL is nonzero if DECL is a partial specialization. */
2466 check_default_tmpl_args (tree decl, tree parms, int is_primary, int is_partial)
2469 int last_level_to_check;
2474 A default template-argument shall not be specified in a
2475 function template declaration or a function template definition, nor
2476 in the template-parameter-list of the definition of a member of a
2479 if (TREE_CODE (CP_DECL_CONTEXT (decl)) == FUNCTION_DECL)
2480 /* You can't have a function template declaration in a local
2481 scope, nor you can you define a member of a class template in a
2485 if (current_class_type
2486 && !TYPE_BEING_DEFINED (current_class_type)
2487 && DECL_LANG_SPECIFIC (decl)
2488 /* If this is either a friend defined in the scope of the class
2489 or a member function. */
2490 && (DECL_FUNCTION_MEMBER_P (decl)
2491 ? same_type_p (DECL_CONTEXT (decl), current_class_type)
2492 : DECL_FRIEND_CONTEXT (decl)
2493 ? same_type_p (DECL_FRIEND_CONTEXT (decl), current_class_type)
2495 /* And, if it was a member function, it really was defined in
2496 the scope of the class. */
2497 && (!DECL_FUNCTION_MEMBER_P (decl)
2498 || DECL_INITIALIZED_IN_CLASS_P (decl)))
2499 /* We already checked these parameters when the template was
2500 declared, so there's no need to do it again now. This function
2501 was defined in class scope, but we're processing it's body now
2502 that the class is complete. */
2507 If a template-parameter has a default template-argument, all
2508 subsequent template-parameters shall have a default
2509 template-argument supplied. */
2510 for (parm_level = parms; parm_level; parm_level = TREE_CHAIN (parm_level))
2512 tree inner_parms = TREE_VALUE (parm_level);
2513 int ntparms = TREE_VEC_LENGTH (inner_parms);
2514 int seen_def_arg_p = 0;
2517 for (i = 0; i < ntparms; ++i)
2519 tree parm = TREE_VEC_ELT (inner_parms, i);
2520 if (TREE_PURPOSE (parm))
2522 else if (seen_def_arg_p)
2524 error ("no default argument for `%D'", TREE_VALUE (parm));
2525 /* For better subsequent error-recovery, we indicate that
2526 there should have been a default argument. */
2527 TREE_PURPOSE (parm) = error_mark_node;
2532 if (TREE_CODE (decl) != TYPE_DECL || is_partial || !is_primary)
2533 /* For an ordinary class template, default template arguments are
2534 allowed at the innermost level, e.g.:
2535 template <class T = int>
2537 but, in a partial specialization, they're not allowed even
2538 there, as we have in [temp.class.spec]:
2540 The template parameter list of a specialization shall not
2541 contain default template argument values.
2543 So, for a partial specialization, or for a function template,
2544 we look at all of them. */
2547 /* But, for a primary class template that is not a partial
2548 specialization we look at all template parameters except the
2550 parms = TREE_CHAIN (parms);
2552 /* Figure out what error message to issue. */
2553 if (TREE_CODE (decl) == FUNCTION_DECL)
2554 msg = "default template arguments may not be used in function templates";
2555 else if (is_partial)
2556 msg = "default template arguments may not be used in partial specializations";
2558 msg = "default argument for template parameter for class enclosing `%D'";
2560 if (current_class_type && TYPE_BEING_DEFINED (current_class_type))
2561 /* If we're inside a class definition, there's no need to
2562 examine the parameters to the class itself. On the one
2563 hand, they will be checked when the class is defined, and,
2564 on the other, default arguments are valid in things like:
2565 template <class T = double>
2566 struct S { template <class U> void f(U); };
2567 Here the default argument for `S' has no bearing on the
2568 declaration of `f'. */
2569 last_level_to_check = template_class_depth (current_class_type) + 1;
2571 /* Check everything. */
2572 last_level_to_check = 0;
2574 for (parm_level = parms;
2575 parm_level && TMPL_PARMS_DEPTH (parm_level) >= last_level_to_check;
2576 parm_level = TREE_CHAIN (parm_level))
2578 tree inner_parms = TREE_VALUE (parm_level);
2582 ntparms = TREE_VEC_LENGTH (inner_parms);
2583 for (i = 0; i < ntparms; ++i)
2584 if (TREE_PURPOSE (TREE_VEC_ELT (inner_parms, i)))
2592 /* Clear out the default argument so that we are not
2594 TREE_PURPOSE (TREE_VEC_ELT (inner_parms, i)) = NULL_TREE;
2597 /* At this point, if we're still interested in issuing messages,
2598 they must apply to classes surrounding the object declared. */
2600 msg = "default argument for template parameter for class enclosing `%D'";
2604 /* Worker for push_template_decl_real, called via
2605 for_each_template_parm. DATA is really an int, indicating the
2606 level of the parameters we are interested in. If T is a template
2607 parameter of that level, return nonzero. */
2610 template_parm_this_level_p (tree t, void* data)
2612 int this_level = *(int *)data;
2615 if (TREE_CODE (t) == TEMPLATE_PARM_INDEX)
2616 level = TEMPLATE_PARM_LEVEL (t);
2618 level = TEMPLATE_TYPE_LEVEL (t);
2619 return level == this_level;
2622 /* Creates a TEMPLATE_DECL for the indicated DECL using the template
2623 parameters given by current_template_args, or reuses a
2624 previously existing one, if appropriate. Returns the DECL, or an
2625 equivalent one, if it is replaced via a call to duplicate_decls.
2627 If IS_FRIEND is nonzero, DECL is a friend declaration. */
2630 push_template_decl_real (tree decl, int is_friend)
2638 int new_template_p = 0;
2640 /* See if this is a partial specialization. */
2641 is_partial = (DECL_IMPLICIT_TYPEDEF_P (decl)
2642 && TREE_CODE (TREE_TYPE (decl)) != ENUMERAL_TYPE
2643 && CLASSTYPE_TEMPLATE_SPECIALIZATION (TREE_TYPE (decl)));
2645 is_friend |= (TREE_CODE (decl) == FUNCTION_DECL && DECL_FRIEND_P (decl));
2648 /* For a friend, we want the context of the friend function, not
2649 the type of which it is a friend. */
2650 ctx = DECL_CONTEXT (decl);
2651 else if (CP_DECL_CONTEXT (decl)
2652 && TREE_CODE (CP_DECL_CONTEXT (decl)) != NAMESPACE_DECL)
2653 /* In the case of a virtual function, we want the class in which
2655 ctx = CP_DECL_CONTEXT (decl);
2657 /* Otherwise, if we're currently defining some class, the DECL
2658 is assumed to be a member of the class. */
2659 ctx = current_scope ();
2661 if (ctx && TREE_CODE (ctx) == NAMESPACE_DECL)
2664 if (!DECL_CONTEXT (decl))
2665 DECL_CONTEXT (decl) = FROB_CONTEXT (current_namespace);
2667 /* See if this is a primary template. */
2668 primary = template_parm_scope_p ();
2672 if (current_lang_name == lang_name_c)
2673 error ("template with C linkage");
2674 else if (TREE_CODE (decl) == TYPE_DECL
2675 && ANON_AGGRNAME_P (DECL_NAME (decl)))
2676 error ("template class without a name");
2677 else if (TREE_CODE (decl) == FUNCTION_DECL
2678 && DECL_DESTRUCTOR_P (decl))
2682 A destructor shall not be a member template. */
2683 error ("destructor `%D' declared as member template", decl);
2684 return error_mark_node;
2686 else if ((DECL_IMPLICIT_TYPEDEF_P (decl)
2687 && CLASS_TYPE_P (TREE_TYPE (decl)))
2688 || (TREE_CODE (decl) == VAR_DECL && ctx && CLASS_TYPE_P (ctx))
2689 || TREE_CODE (decl) == FUNCTION_DECL)
2692 error ("template declaration of `%#D'", decl);
2695 /* Check to see that the rules regarding the use of default
2696 arguments are not being violated. */
2697 check_default_tmpl_args (decl, current_template_parms,
2698 primary, is_partial);
2701 return process_partial_specialization (decl);
2703 args = current_template_args ();
2706 || TREE_CODE (ctx) == FUNCTION_DECL
2707 || (CLASS_TYPE_P (ctx) && TYPE_BEING_DEFINED (ctx))
2708 || (is_friend && !DECL_TEMPLATE_INFO (decl)))
2710 if (DECL_LANG_SPECIFIC (decl)
2711 && DECL_TEMPLATE_INFO (decl)
2712 && DECL_TI_TEMPLATE (decl))
2713 tmpl = DECL_TI_TEMPLATE (decl);
2714 /* If DECL is a TYPE_DECL for a class-template, then there won't
2715 be DECL_LANG_SPECIFIC. The information equivalent to
2716 DECL_TEMPLATE_INFO is found in TYPE_TEMPLATE_INFO instead. */
2717 else if (DECL_IMPLICIT_TYPEDEF_P (decl)
2718 && TYPE_TEMPLATE_INFO (TREE_TYPE (decl))
2719 && TYPE_TI_TEMPLATE (TREE_TYPE (decl)))
2721 /* Since a template declaration already existed for this
2722 class-type, we must be redeclaring it here. Make sure
2723 that the redeclaration is valid. */
2724 redeclare_class_template (TREE_TYPE (decl),
2725 current_template_parms);
2726 /* We don't need to create a new TEMPLATE_DECL; just use the
2727 one we already had. */
2728 tmpl = TYPE_TI_TEMPLATE (TREE_TYPE (decl));
2732 tmpl = build_template_decl (decl, current_template_parms);
2735 if (DECL_LANG_SPECIFIC (decl)
2736 && DECL_TEMPLATE_SPECIALIZATION (decl))
2738 /* A specialization of a member template of a template
2740 SET_DECL_TEMPLATE_SPECIALIZATION (tmpl);
2741 DECL_TEMPLATE_INFO (tmpl) = DECL_TEMPLATE_INFO (decl);
2742 DECL_TEMPLATE_INFO (decl) = NULL_TREE;
2748 tree a, t, current, parms;
2751 if (TREE_CODE (decl) == TYPE_DECL)
2753 if ((IS_AGGR_TYPE_CODE (TREE_CODE (TREE_TYPE (decl)))
2754 || TREE_CODE (TREE_TYPE (decl)) == ENUMERAL_TYPE)
2755 && TYPE_TEMPLATE_INFO (TREE_TYPE (decl))
2756 && TYPE_TI_TEMPLATE (TREE_TYPE (decl)))
2757 tmpl = TYPE_TI_TEMPLATE (TREE_TYPE (decl));
2760 error ("`%D' does not declare a template type", decl);
2764 else if (!DECL_LANG_SPECIFIC (decl) || !DECL_TEMPLATE_INFO (decl))
2766 error ("template definition of non-template `%#D'", decl);
2770 tmpl = DECL_TI_TEMPLATE (decl);
2772 if (is_member_template (tmpl)
2773 && DECL_FUNCTION_TEMPLATE_P (tmpl)
2774 && DECL_TEMPLATE_INFO (decl) && DECL_TI_ARGS (decl)
2775 && DECL_TEMPLATE_SPECIALIZATION (decl))
2779 /* The declaration is a specialization of a member
2780 template, declared outside the class. Therefore, the
2781 innermost template arguments will be NULL, so we
2782 replace them with the arguments determined by the
2783 earlier call to check_explicit_specialization. */
2784 args = DECL_TI_ARGS (decl);
2787 = build_template_decl (decl, current_template_parms);
2788 DECL_TEMPLATE_RESULT (new_tmpl) = decl;
2789 TREE_TYPE (new_tmpl) = TREE_TYPE (decl);
2790 DECL_TI_TEMPLATE (decl) = new_tmpl;
2791 SET_DECL_TEMPLATE_SPECIALIZATION (new_tmpl);
2792 DECL_TEMPLATE_INFO (new_tmpl)
2793 = tree_cons (tmpl, args, NULL_TREE);
2795 register_specialization (new_tmpl,
2796 most_general_template (tmpl),
2801 /* Make sure the template headers we got make sense. */
2803 parms = DECL_TEMPLATE_PARMS (tmpl);
2804 i = TMPL_PARMS_DEPTH (parms);
2805 if (TMPL_ARGS_DEPTH (args) != i)
2807 error ("expected %d levels of template parms for `%#D', got %d",
2808 i, decl, TMPL_ARGS_DEPTH (args));
2811 for (current = decl; i > 0; --i, parms = TREE_CHAIN (parms))
2813 a = TMPL_ARGS_LEVEL (args, i);
2814 t = INNERMOST_TEMPLATE_PARMS (parms);
2816 if (TREE_VEC_LENGTH (t) != TREE_VEC_LENGTH (a))
2818 if (current == decl)
2819 error ("got %d template parameters for `%#D'",
2820 TREE_VEC_LENGTH (a), decl);
2822 error ("got %d template parameters for `%#T'",
2823 TREE_VEC_LENGTH (a), current);
2824 error (" but %d required", TREE_VEC_LENGTH (t));
2827 /* Perhaps we should also check that the parms are used in the
2828 appropriate qualifying scopes in the declarator? */
2830 if (current == decl)
2833 current = TYPE_CONTEXT (current);
2837 DECL_TEMPLATE_RESULT (tmpl) = decl;
2838 TREE_TYPE (tmpl) = TREE_TYPE (decl);
2840 /* Push template declarations for global functions and types. Note
2841 that we do not try to push a global template friend declared in a
2842 template class; such a thing may well depend on the template
2843 parameters of the class. */
2844 if (new_template_p && !ctx
2845 && !(is_friend && template_class_depth (current_class_type) > 0))
2846 tmpl = pushdecl_namespace_level (tmpl);
2850 DECL_PRIMARY_TEMPLATE (tmpl) = tmpl;
2851 if (DECL_CONV_FN_P (tmpl))
2853 int depth = TMPL_PARMS_DEPTH (DECL_TEMPLATE_PARMS (tmpl));
2855 /* It is a conversion operator. See if the type converted to
2856 depends on innermost template operands. */
2858 if (for_each_template_parm (TREE_TYPE (TREE_TYPE (tmpl)),
2859 template_parm_this_level_p,
2862 DECL_TEMPLATE_CONV_FN_P (tmpl) = 1;
2866 info = tree_cons (tmpl, args, NULL_TREE);
2868 if (DECL_IMPLICIT_TYPEDEF_P (decl))
2870 SET_TYPE_TEMPLATE_INFO (TREE_TYPE (tmpl), info);
2871 if ((!ctx || TREE_CODE (ctx) != FUNCTION_DECL)
2872 && TREE_CODE (TREE_TYPE (decl)) != ENUMERAL_TYPE
2873 /* Don't change the name if we've already set it up. */
2874 && !IDENTIFIER_TEMPLATE (DECL_NAME (decl)))
2875 DECL_NAME (decl) = classtype_mangled_name (TREE_TYPE (decl));
2877 else if (DECL_LANG_SPECIFIC (decl))
2878 DECL_TEMPLATE_INFO (decl) = info;
2880 return DECL_TEMPLATE_RESULT (tmpl);
2884 push_template_decl (tree decl)
2886 return push_template_decl_real (decl, 0);
2889 /* Called when a class template TYPE is redeclared with the indicated
2890 template PARMS, e.g.:
2892 template <class T> struct S;
2893 template <class T> struct S {}; */
2896 redeclare_class_template (tree type, tree parms)
2902 if (!TYPE_TEMPLATE_INFO (type))
2904 error ("`%T' is not a template type", type);
2908 tmpl = TYPE_TI_TEMPLATE (type);
2909 if (!PRIMARY_TEMPLATE_P (tmpl))
2910 /* The type is nested in some template class. Nothing to worry
2911 about here; there are no new template parameters for the nested
2915 parms = INNERMOST_TEMPLATE_PARMS (parms);
2916 tmpl_parms = DECL_INNERMOST_TEMPLATE_PARMS (tmpl);
2918 if (TREE_VEC_LENGTH (parms) != TREE_VEC_LENGTH (tmpl_parms))
2920 cp_error_at ("previous declaration `%D'", tmpl);
2921 error ("used %d template parameter%s instead of %d",
2922 TREE_VEC_LENGTH (tmpl_parms),
2923 TREE_VEC_LENGTH (tmpl_parms) == 1 ? "" : "s",
2924 TREE_VEC_LENGTH (parms));
2928 for (i = 0; i < TREE_VEC_LENGTH (tmpl_parms); ++i)
2930 tree tmpl_parm = TREE_VALUE (TREE_VEC_ELT (tmpl_parms, i));
2931 tree parm = TREE_VALUE (TREE_VEC_ELT (parms, i));
2932 tree tmpl_default = TREE_PURPOSE (TREE_VEC_ELT (tmpl_parms, i));
2933 tree parm_default = TREE_PURPOSE (TREE_VEC_ELT (parms, i));
2935 if (TREE_CODE (tmpl_parm) != TREE_CODE (parm))
2937 cp_error_at ("template parameter `%#D'", tmpl_parm);
2938 error ("redeclared here as `%#D'", parm);
2942 if (tmpl_default != NULL_TREE && parm_default != NULL_TREE)
2944 /* We have in [temp.param]:
2946 A template-parameter may not be given default arguments
2947 by two different declarations in the same scope. */
2948 error ("redefinition of default argument for `%#D'", parm);
2949 error ("%H original definition appeared here",
2950 &DECL_SOURCE_LOCATION (tmpl_parm));
2954 if (parm_default != NULL_TREE)
2955 /* Update the previous template parameters (which are the ones
2956 that will really count) with the new default value. */
2957 TREE_PURPOSE (TREE_VEC_ELT (tmpl_parms, i)) = parm_default;
2958 else if (tmpl_default != NULL_TREE)
2959 /* Update the new parameters, too; they'll be used as the
2960 parameters for any members. */
2961 TREE_PURPOSE (TREE_VEC_ELT (parms, i)) = tmpl_default;
2965 /* Attempt to convert the non-type template parameter EXPR to the
2966 indicated TYPE. If the conversion is successful, return the
2967 converted value. If the conversion is unsuccessful, return
2968 NULL_TREE if we issued an error message, or error_mark_node if we
2969 did not. We issue error messages for out-and-out bad template
2970 parameters, but not simply because the conversion failed, since we
2971 might be just trying to do argument deduction. By the time this
2972 function is called, neither TYPE nor EXPR may make use of template
2976 convert_nontype_argument (tree type, tree expr)
2978 tree expr_type = TREE_TYPE (expr);
2980 /* A template-argument for a non-type, non-template
2981 template-parameter shall be one of:
2983 --an integral constant-expression of integral or enumeration
2986 --the name of a non-type template-parameter; or
2988 --the name of an object or function with external linkage,
2989 including function templates and function template-ids but
2990 excluding non-static class members, expressed as id-expression;
2993 --the address of an object or function with external linkage,
2994 including function templates and function template-ids but
2995 excluding non-static class members, expressed as & id-expression
2996 where the & is optional if the name refers to a function or
2999 --a pointer to member expressed as described in _expr.unary.op_. */
3001 /* An integral constant-expression can include const variables or
3002 enumerators. Simplify things by folding them to their values,
3003 unless we're about to bind the declaration to a reference
3005 if (INTEGRAL_TYPE_P (expr_type)
3006 && TREE_CODE (type) != REFERENCE_TYPE)
3007 expr = decl_constant_value (expr);
3009 if (is_overloaded_fn (expr))
3010 /* OK for now. We'll check that it has external linkage later.
3011 Check this first since if expr_type is the unknown_type_node
3012 we would otherwise complain below. */
3014 else if (TYPE_PTR_TO_MEMBER_P (expr_type))
3016 if (TREE_CODE (expr) != PTRMEM_CST)
3019 else if (TYPE_PTR_P (expr_type)
3020 || TREE_CODE (expr_type) == ARRAY_TYPE
3021 || TREE_CODE (type) == REFERENCE_TYPE
3022 /* If expr is the address of an overloaded function, we
3023 will get the unknown_type_node at this point. */
3024 || expr_type == unknown_type_node)
3030 if (TREE_CODE (expr_type) == ARRAY_TYPE
3031 || (TREE_CODE (type) == REFERENCE_TYPE
3032 && TREE_CODE (e) != ADDR_EXPR))
3036 if (TREE_CODE (e) != ADDR_EXPR)
3039 error ("`%E' is not a valid template argument", expr);
3040 if (TYPE_PTR_P (expr_type))
3042 if (TREE_CODE (TREE_TYPE (expr_type)) == FUNCTION_TYPE)
3043 error ("it must be the address of a function with external linkage");
3045 error ("it must be the address of an object with external linkage");
3047 else if (TYPE_PTR_TO_MEMBER_P (expr_type))
3048 error ("it must be a pointer-to-member of the form `&X::Y'");
3053 referent = TREE_OPERAND (e, 0);
3054 STRIP_NOPS (referent);
3057 if (TREE_CODE (referent) == STRING_CST)
3059 error ("string literal %E is not a valid template argument because it is the address of an object with static linkage",
3064 if (TREE_CODE (referent) == SCOPE_REF)
3065 referent = TREE_OPERAND (referent, 1);
3067 if (is_overloaded_fn (referent))
3068 /* We'll check that it has external linkage later. */
3070 else if (TREE_CODE (referent) != VAR_DECL)
3072 else if (!DECL_EXTERNAL_LINKAGE_P (referent))
3074 error ("address of non-extern `%E' cannot be used as template argument", referent);
3075 return error_mark_node;
3078 else if (INTEGRAL_TYPE_P (expr_type) || TYPE_PTR_TO_MEMBER_P (expr_type))
3080 if (! TREE_CONSTANT (expr))
3083 error ("non-constant `%E' cannot be used as template argument",
3091 error ("type '%T' cannot be used as a value for a non-type "
3092 "template-parameter", expr);
3093 else if (DECL_P (expr))
3094 error ("invalid use of '%D' as a non-type template-argument", expr);
3096 error ("invalid use of '%E' as a non-type template-argument", expr);
3101 switch (TREE_CODE (type))
3106 /* For a non-type template-parameter of integral or enumeration
3107 type, integral promotions (_conv.prom_) and integral
3108 conversions (_conv.integral_) are applied. */
3109 if (!INTEGRAL_TYPE_P (expr_type))
3110 return error_mark_node;
3112 /* It's safe to call digest_init in this case; we know we're
3113 just converting one integral constant expression to another. */
3114 expr = digest_init (type, expr, (tree*) 0);
3116 if (TREE_CODE (expr) != INTEGER_CST)
3117 /* Curiously, some TREE_CONSTANT integral expressions do not
3118 simplify to integer constants. For example, `3 % 0',
3119 remains a TRUNC_MOD_EXPR. */
3128 /* For a non-type template-parameter of type pointer to data
3129 member, qualification conversions (_conv.qual_) are
3131 e = perform_qualification_conversions (type, expr);
3132 if (TREE_CODE (e) == NOP_EXPR)
3133 /* The call to perform_qualification_conversions will
3134 insert a NOP_EXPR over EXPR to do express conversion,
3135 if necessary. But, that will confuse us if we use
3136 this (converted) template parameter to instantiate
3137 another template; then the thing will not look like a
3138 valid template argument. So, just make a new
3139 constant, of the appropriate type. */
3140 e = make_ptrmem_cst (type, PTRMEM_CST_MEMBER (expr));
3146 tree type_pointed_to = TREE_TYPE (type);
3148 if (TREE_CODE (type_pointed_to) == FUNCTION_TYPE)
3150 /* For a non-type template-parameter of type pointer to
3151 function, only the function-to-pointer conversion
3152 (_conv.func_) is applied. If the template-argument
3153 represents a set of overloaded functions (or a pointer to
3154 such), the matching function is selected from the set
3159 if (TREE_CODE (expr) == ADDR_EXPR)
3160 fns = TREE_OPERAND (expr, 0);
3164 fn = instantiate_type (type_pointed_to, fns, tf_none);
3166 if (fn == error_mark_node)
3167 return error_mark_node;
3169 if (!DECL_EXTERNAL_LINKAGE_P (fn))
3171 if (really_overloaded_fn (fns))
3172 return error_mark_node;
3177 expr = build_unary_op (ADDR_EXPR, fn, 0);
3179 my_friendly_assert (same_type_p (type, TREE_TYPE (expr)),
3185 /* For a non-type template-parameter of type pointer to
3186 object, qualification conversions (_conv.qual_) and the
3187 array-to-pointer conversion (_conv.array_) are applied.
3188 [Note: In particular, neither the null pointer conversion
3189 (_conv.ptr_) nor the derived-to-base conversion
3190 (_conv.ptr_) are applied. Although 0 is a valid
3191 template-argument for a non-type template-parameter of
3192 integral type, it is not a valid template-argument for a
3193 non-type template-parameter of pointer type.]
3195 The call to decay_conversion performs the
3196 array-to-pointer conversion, if appropriate. */
3197 expr = decay_conversion (expr);
3199 if (expr == error_mark_node)
3200 return error_mark_node;
3202 return perform_qualification_conversions (type, expr);
3207 case REFERENCE_TYPE:
3209 tree type_referred_to = TREE_TYPE (type);
3211 /* If this expression already has reference type, get the
3212 underlying object. */
3213 if (TREE_CODE (expr_type) == REFERENCE_TYPE)
3215 if (TREE_CODE (expr) == NOP_EXPR
3216 && TREE_CODE (TREE_OPERAND (expr, 0)) == ADDR_EXPR)
3218 my_friendly_assert (TREE_CODE (expr) == ADDR_EXPR, 20000604);
3219 expr = TREE_OPERAND (expr, 0);
3220 expr_type = TREE_TYPE (expr);
3223 if (TREE_CODE (type_referred_to) == FUNCTION_TYPE)
3225 /* For a non-type template-parameter of type reference to
3226 function, no conversions apply. If the
3227 template-argument represents a set of overloaded
3228 functions, the matching function is selected from the
3229 set (_over.over_). */
3232 fn = instantiate_type (type_referred_to, expr, tf_none);
3234 if (fn == error_mark_node)
3235 return error_mark_node;
3237 if (!DECL_EXTERNAL_LINKAGE_P (fn))
3239 if (really_overloaded_fn (expr))
3240 /* Don't issue an error here; we might get a different
3241 function if the overloading had worked out
3243 return error_mark_node;
3248 my_friendly_assert (same_type_p (type_referred_to,
3256 /* For a non-type template-parameter of type reference to
3257 object, no conversions apply. The type referred to by the
3258 reference may be more cv-qualified than the (otherwise
3259 identical) type of the template-argument. The
3260 template-parameter is bound directly to the
3261 template-argument, which must be an lvalue. */
3262 if (!same_type_p (TYPE_MAIN_VARIANT (expr_type),
3263 TYPE_MAIN_VARIANT (type_referred_to))
3264 || !at_least_as_qualified_p (type_referred_to,
3266 || !real_lvalue_p (expr))
3267 return error_mark_node;
3270 cxx_mark_addressable (expr);
3271 return build_nop (type, build_address (expr));
3277 my_friendly_assert (TYPE_PTRMEMFUNC_P (type), 20010112);
3279 /* For a non-type template-parameter of type pointer to member
3280 function, no conversions apply. If the template-argument
3281 represents a set of overloaded member functions, the
3282 matching member function is selected from the set
3285 if (!TYPE_PTRMEMFUNC_P (expr_type) &&
3286 expr_type != unknown_type_node)
3287 return error_mark_node;
3289 if (TREE_CODE (expr) == PTRMEM_CST)
3291 /* A ptr-to-member constant. */
3292 if (!same_type_p (type, expr_type))
3293 return error_mark_node;
3298 if (TREE_CODE (expr) != ADDR_EXPR)
3299 return error_mark_node;
3301 expr = instantiate_type (type, expr, tf_none);
3303 if (expr == error_mark_node)
3304 return error_mark_node;
3306 my_friendly_assert (same_type_p (type, TREE_TYPE (expr)),
3313 /* All non-type parameters must have one of these types. */
3318 return error_mark_node;
3321 /* Return 1 if PARM_PARMS and ARG_PARMS matches using rule for
3322 template template parameters. Both PARM_PARMS and ARG_PARMS are
3323 vectors of TREE_LIST nodes containing TYPE_DECL, TEMPLATE_DECL
3326 ARG_PARMS may contain more parameters than PARM_PARMS. If this is
3327 the case, then extra parameters must have default arguments.
3329 Consider the example:
3330 template <class T, class Allocator = allocator> class vector;
3331 template<template <class U> class TT> class C;
3333 C<vector> is a valid instantiation. PARM_PARMS for the above code
3334 contains a TYPE_DECL (for U), ARG_PARMS contains two TYPE_DECLs (for
3335 T and Allocator) and OUTER_ARGS contains the argument that is used to
3336 substitute the TT parameter. */
3339 coerce_template_template_parms (tree parm_parms,
3341 tsubst_flags_t complain,
3345 int nparms, nargs, i;
3348 my_friendly_assert (TREE_CODE (parm_parms) == TREE_VEC, 0);
3349 my_friendly_assert (TREE_CODE (arg_parms) == TREE_VEC, 0);
3351 nparms = TREE_VEC_LENGTH (parm_parms);
3352 nargs = TREE_VEC_LENGTH (arg_parms);
3354 /* The rule here is opposite of coerce_template_parms. */
3357 && TREE_PURPOSE (TREE_VEC_ELT (arg_parms, nparms)) == NULL_TREE))
3360 for (i = 0; i < nparms; ++i)
3362 parm = TREE_VALUE (TREE_VEC_ELT (parm_parms, i));
3363 arg = TREE_VALUE (TREE_VEC_ELT (arg_parms, i));
3365 if (arg == NULL_TREE || arg == error_mark_node
3366 || parm == NULL_TREE || parm == error_mark_node)
3369 if (TREE_CODE (arg) != TREE_CODE (parm))
3372 switch (TREE_CODE (parm))
3378 /* We encounter instantiations of templates like
3379 template <template <template <class> class> class TT>
3382 tree parmparm = DECL_INNERMOST_TEMPLATE_PARMS (parm);
3383 tree argparm = DECL_INNERMOST_TEMPLATE_PARMS (arg);
3385 if (!coerce_template_template_parms
3386 (parmparm, argparm, complain, in_decl, outer_args))
3392 /* The tsubst call is used to handle cases such as
3393 template <class T, template <T> class TT> class D;
3394 i.e. the parameter list of TT depends on earlier parameters. */
3396 (tsubst (TREE_TYPE (parm), outer_args, complain, in_decl),
3408 /* Convert the indicated template ARG as necessary to match the
3409 indicated template PARM. Returns the converted ARG, or
3410 error_mark_node if the conversion was unsuccessful. Error and
3411 warning messages are issued under control of COMPLAIN. This
3412 conversion is for the Ith parameter in the parameter list. ARGS is
3413 the full set of template arguments deduced so far. */
3416 convert_template_argument (tree parm,
3419 tsubst_flags_t complain,
3425 int is_type, requires_type, is_tmpl_type, requires_tmpl_type;
3427 inner_args = INNERMOST_TEMPLATE_ARGS (args);
3429 if (TREE_CODE (arg) == TREE_LIST
3430 && TREE_CODE (TREE_VALUE (arg)) == OFFSET_REF)
3432 /* The template argument was the name of some
3433 member function. That's usually
3434 invalid, but static members are OK. In any
3435 case, grab the underlying fields/functions
3436 and issue an error later if required. */
3437 arg = TREE_VALUE (arg);
3438 TREE_TYPE (arg) = unknown_type_node;
3441 requires_tmpl_type = TREE_CODE (parm) == TEMPLATE_DECL;
3442 requires_type = (TREE_CODE (parm) == TYPE_DECL
3443 || requires_tmpl_type);
3445 is_tmpl_type = ((TREE_CODE (arg) == TEMPLATE_DECL
3446 && TREE_CODE (DECL_TEMPLATE_RESULT (arg)) == TYPE_DECL)
3447 || TREE_CODE (arg) == TEMPLATE_TEMPLATE_PARM
3448 || TREE_CODE (arg) == UNBOUND_CLASS_TEMPLATE);
3451 && (TREE_CODE (arg) == TEMPLATE_TEMPLATE_PARM
3452 || TREE_CODE (arg) == UNBOUND_CLASS_TEMPLATE))
3453 arg = TYPE_STUB_DECL (arg);
3455 is_type = TYPE_P (arg) || is_tmpl_type;
3457 if (requires_type && ! is_type && TREE_CODE (arg) == SCOPE_REF
3458 && TREE_CODE (TREE_OPERAND (arg, 0)) == TEMPLATE_TYPE_PARM)
3460 pedwarn ("to refer to a type member of a template parameter, use `typename %E'", arg);
3462 arg = make_typename_type (TREE_OPERAND (arg, 0),
3463 TREE_OPERAND (arg, 1),
3464 complain & tf_error);
3467 if (is_type != requires_type)
3471 if (complain & tf_error)
3473 error ("type/value mismatch at argument %d in template parameter list for `%D'",
3476 error (" expected a constant of type `%T', got `%T'",
3478 (is_tmpl_type ? DECL_NAME (arg) : arg));
3479 else if (requires_tmpl_type)
3480 error (" expected a class template, got `%E'", arg);
3482 error (" expected a type, got `%E'", arg);
3485 return error_mark_node;
3487 if (is_tmpl_type ^ requires_tmpl_type)
3489 if (in_decl && (complain & tf_error))
3491 error ("type/value mismatch at argument %d in template parameter list for `%D'",
3494 error (" expected a type, got `%T'", DECL_NAME (arg));
3496 error (" expected a class template, got `%T'", arg);
3498 return error_mark_node;
3503 if (requires_tmpl_type)
3505 if (TREE_CODE (TREE_TYPE (arg)) == UNBOUND_CLASS_TEMPLATE)
3506 /* The number of argument required is not known yet.
3507 Just accept it for now. */
3508 val = TREE_TYPE (arg);
3511 tree parmparm = DECL_INNERMOST_TEMPLATE_PARMS (parm);
3512 tree argparm = DECL_INNERMOST_TEMPLATE_PARMS (arg);
3514 if (coerce_template_template_parms (parmparm, argparm,
3520 /* TEMPLATE_TEMPLATE_PARM node is preferred over
3522 if (val != error_mark_node
3523 && DECL_TEMPLATE_TEMPLATE_PARM_P (val))
3524 val = TREE_TYPE (val);
3528 if (in_decl && (complain & tf_error))
3530 error ("type/value mismatch at argument %d in template parameter list for `%D'",
3532 error (" expected a template of type `%D', got `%D'", parm, arg);
3535 val = error_mark_node;
3540 val = groktypename (arg);
3544 tree t = tsubst (TREE_TYPE (parm), args, complain, in_decl);
3546 if (invalid_nontype_parm_type_p (t, complain))
3547 return error_mark_node;
3549 if (!uses_template_parms (arg) && !uses_template_parms (t))
3550 /* We used to call digest_init here. However, digest_init
3551 will report errors, which we don't want when complain
3552 is zero. More importantly, digest_init will try too
3553 hard to convert things: for example, `0' should not be
3554 converted to pointer type at this point according to
3555 the standard. Accepting this is not merely an
3556 extension, since deciding whether or not these
3557 conversions can occur is part of determining which
3558 function template to call, or whether a given explicit
3559 argument specification is valid. */
3560 val = convert_nontype_argument (t, arg);
3564 if (val == NULL_TREE)
3565 val = error_mark_node;
3566 else if (val == error_mark_node && (complain & tf_error))
3567 error ("could not convert template argument `%E' to `%T'",
3574 /* Convert all template arguments to their appropriate types, and
3575 return a vector containing the innermost resulting template
3576 arguments. If any error occurs, return error_mark_node. Error and
3577 warning messages are issued under control of COMPLAIN.
3579 If REQUIRE_ALL_ARGUMENTS is nonzero, all arguments must be
3580 provided in ARGLIST, or else trailing parameters must have default
3581 values. If REQUIRE_ALL_ARGUMENTS is zero, we will attempt argument
3582 deduction for any unspecified trailing arguments. */
3585 coerce_template_parms (tree parms,
3588 tsubst_flags_t complain,
3589 int require_all_arguments)
3591 int nparms, nargs, i, lost = 0;
3594 tree new_inner_args;
3596 inner_args = INNERMOST_TEMPLATE_ARGS (args);
3597 nargs = inner_args ? NUM_TMPL_ARGS (inner_args) : 0;
3598 nparms = TREE_VEC_LENGTH (parms);
3602 && require_all_arguments
3603 && TREE_PURPOSE (TREE_VEC_ELT (parms, nargs)) == NULL_TREE))
3605 if (complain & tf_error)
3607 error ("wrong number of template arguments (%d, should be %d)",
3611 cp_error_at ("provided for `%D'", in_decl);
3614 return error_mark_node;
3617 new_inner_args = make_tree_vec (nparms);
3618 new_args = add_outermost_template_args (args, new_inner_args);
3619 for (i = 0; i < nparms; i++)
3624 /* Get the Ith template parameter. */
3625 parm = TREE_VEC_ELT (parms, i);
3627 /* Calculate the Ith argument. */
3629 arg = TREE_VEC_ELT (inner_args, i);
3630 else if (require_all_arguments)
3631 /* There must be a default arg in this case. */
3632 arg = tsubst_template_arg (TREE_PURPOSE (parm), new_args,
3637 my_friendly_assert (arg, 20030727);
3638 if (arg == error_mark_node)
3639 error ("template argument %d is invalid", i + 1);
3641 arg = convert_template_argument (TREE_VALUE (parm),
3642 arg, new_args, complain, i,
3645 if (arg == error_mark_node)
3647 TREE_VEC_ELT (new_inner_args, i) = arg;
3651 return error_mark_node;
3653 return new_inner_args;
3656 /* Returns 1 if template args OT and NT are equivalent. */
3659 template_args_equal (tree ot, tree nt)
3664 if (TREE_CODE (nt) == TREE_VEC)
3665 /* For member templates */
3666 return TREE_CODE (ot) == TREE_VEC && comp_template_args (ot, nt);
3667 else if (TYPE_P (nt))
3668 return TYPE_P (ot) && same_type_p (ot, nt);
3669 else if (TREE_CODE (ot) == TREE_VEC || TYPE_P (ot))
3672 return cp_tree_equal (ot, nt);
3675 /* Returns 1 iff the OLDARGS and NEWARGS are in fact identical sets
3676 of template arguments. Returns 0 otherwise. */
3679 comp_template_args (tree oldargs, tree newargs)
3683 if (TREE_VEC_LENGTH (oldargs) != TREE_VEC_LENGTH (newargs))
3686 for (i = 0; i < TREE_VEC_LENGTH (oldargs); ++i)
3688 tree nt = TREE_VEC_ELT (newargs, i);
3689 tree ot = TREE_VEC_ELT (oldargs, i);
3691 if (! template_args_equal (ot, nt))
3697 /* Given class template name and parameter list, produce a user-friendly name
3698 for the instantiation. */
3701 mangle_class_name_for_template (const char* name, tree parms, tree arglist)
3703 static struct obstack scratch_obstack;
3704 static char *scratch_firstobj;
3707 if (!scratch_firstobj)
3708 gcc_obstack_init (&scratch_obstack);
3710 obstack_free (&scratch_obstack, scratch_firstobj);
3711 scratch_firstobj = obstack_alloc (&scratch_obstack, 1);
3713 #define ccat(C) obstack_1grow (&scratch_obstack, (C));
3714 #define cat(S) obstack_grow (&scratch_obstack, (S), strlen (S))
3718 nparms = TREE_VEC_LENGTH (parms);
3719 arglist = INNERMOST_TEMPLATE_ARGS (arglist);
3720 my_friendly_assert (nparms == TREE_VEC_LENGTH (arglist), 268);
3721 for (i = 0; i < nparms; i++)
3723 tree parm = TREE_VALUE (TREE_VEC_ELT (parms, i));
3724 tree arg = TREE_VEC_ELT (arglist, i);
3729 if (TREE_CODE (parm) == TYPE_DECL)
3731 cat (type_as_string (arg, TFF_CHASE_TYPEDEF));
3734 else if (TREE_CODE (parm) == TEMPLATE_DECL)
3736 if (TREE_CODE (arg) == TEMPLATE_DECL)
3738 /* Already substituted with real template. Just output
3739 the template name here */
3740 tree context = DECL_CONTEXT (arg);
3743 /* The template may be defined in a namespace, or
3744 may be a member template. */
3745 my_friendly_assert (TREE_CODE (context) == NAMESPACE_DECL
3746 || CLASS_TYPE_P (context),
3748 cat(decl_as_string (DECL_CONTEXT (arg), TFF_PLAIN_IDENTIFIER));
3751 cat (IDENTIFIER_POINTER (DECL_NAME (arg)));
3754 /* Output the parameter declaration */
3755 cat (type_as_string (arg, TFF_CHASE_TYPEDEF));
3759 my_friendly_assert (TREE_CODE (parm) == PARM_DECL, 269);
3761 /* No need to check arglist against parmlist here; we did that
3762 in coerce_template_parms, called from lookup_template_class. */
3763 cat (expr_as_string (arg, TFF_PLAIN_IDENTIFIER));
3766 char *bufp = obstack_next_free (&scratch_obstack);
3768 while (bufp[offset - 1] == ' ')
3770 obstack_blank_fast (&scratch_obstack, offset);
3772 /* B<C<char> >, not B<C<char>> */
3773 if (bufp[offset - 1] == '>')
3778 return (char *) obstack_base (&scratch_obstack);
3782 classtype_mangled_name (tree t)
3784 if (CLASSTYPE_TEMPLATE_INFO (t)
3785 /* Specializations have already had their names set up in
3786 lookup_template_class. */
3787 && !CLASSTYPE_TEMPLATE_SPECIALIZATION (t))
3789 tree tmpl = most_general_template (CLASSTYPE_TI_TEMPLATE (t));
3791 /* For non-primary templates, the template parameters are
3792 implicit from their surrounding context. */
3793 if (PRIMARY_TEMPLATE_P (tmpl))
3795 tree name = DECL_NAME (tmpl);
3796 char *mangled_name = mangle_class_name_for_template
3797 (IDENTIFIER_POINTER (name),
3798 DECL_INNERMOST_TEMPLATE_PARMS (tmpl),
3799 CLASSTYPE_TI_ARGS (t));
3800 tree id = get_identifier (mangled_name);
3801 IDENTIFIER_TEMPLATE (id) = name;
3806 return TYPE_IDENTIFIER (t);
3810 add_pending_template (tree d)
3812 tree ti = (TYPE_P (d)
3813 ? CLASSTYPE_TEMPLATE_INFO (d)
3814 : DECL_TEMPLATE_INFO (d));
3818 if (TI_PENDING_TEMPLATE_FLAG (ti))
3821 /* We are called both from instantiate_decl, where we've already had a
3822 tinst_level pushed, and instantiate_template, where we haven't.
3824 level = !(current_tinst_level && TINST_DECL (current_tinst_level) == d);
3827 push_tinst_level (d);
3829 pt = tree_cons (current_tinst_level, d, NULL_TREE);
3830 if (last_pending_template)
3831 TREE_CHAIN (last_pending_template) = pt;
3833 pending_templates = pt;
3835 last_pending_template = pt;
3837 TI_PENDING_TEMPLATE_FLAG (ti) = 1;
3844 /* Return a TEMPLATE_ID_EXPR corresponding to the indicated FNS and
3845 ARGLIST. Valid choices for FNS are given in the cp-tree.def
3846 documentation for TEMPLATE_ID_EXPR. */
3849 lookup_template_function (tree fns, tree arglist)
3853 if (fns == error_mark_node || arglist == error_mark_node)
3854 return error_mark_node;
3856 my_friendly_assert (!arglist || TREE_CODE (arglist) == TREE_VEC, 20030726);
3857 if (fns == NULL_TREE
3858 || TREE_CODE (fns) == FUNCTION_DECL)
3860 error ("non-template used as template");
3861 return error_mark_node;
3864 my_friendly_assert (TREE_CODE (fns) == TEMPLATE_DECL
3865 || TREE_CODE (fns) == OVERLOAD
3867 || TREE_CODE (fns) == IDENTIFIER_NODE,
3870 if (BASELINK_P (fns))
3872 BASELINK_FUNCTIONS (fns) = build (TEMPLATE_ID_EXPR,
3874 BASELINK_FUNCTIONS (fns),
3879 type = TREE_TYPE (fns);
3880 if (TREE_CODE (fns) == OVERLOAD || !type)
3881 type = unknown_type_node;
3883 return build (TEMPLATE_ID_EXPR, type, fns, arglist);
3886 /* Within the scope of a template class S<T>, the name S gets bound
3887 (in build_self_reference) to a TYPE_DECL for the class, not a
3888 TEMPLATE_DECL. If DECL is a TYPE_DECL for current_class_type,
3889 or one of its enclosing classes, and that type is a template,
3890 return the associated TEMPLATE_DECL. Otherwise, the original
3891 DECL is returned. */
3894 maybe_get_template_decl_from_type_decl (tree decl)
3896 return (decl != NULL_TREE
3897 && TREE_CODE (decl) == TYPE_DECL
3898 && DECL_ARTIFICIAL (decl)
3899 && CLASS_TYPE_P (TREE_TYPE (decl))
3900 && CLASSTYPE_TEMPLATE_INFO (TREE_TYPE (decl)))
3901 ? CLASSTYPE_TI_TEMPLATE (TREE_TYPE (decl)) : decl;
3904 /* Given an IDENTIFIER_NODE (type TEMPLATE_DECL) and a chain of
3905 parameters, find the desired type.
3907 D1 is the PTYPENAME terminal, and ARGLIST is the list of arguments.
3909 IN_DECL, if non-NULL, is the template declaration we are trying to
3912 If ENTERING_SCOPE is nonzero, we are about to enter the scope of
3913 the class we are looking up.
3915 Issue error and warning messages under control of COMPLAIN.
3917 If the template class is really a local class in a template
3918 function, then the FUNCTION_CONTEXT is the function in which it is
3919 being instantiated. */
3922 lookup_template_class (tree d1,
3927 tsubst_flags_t complain)
3929 tree template = NULL_TREE, parmlist;
3932 timevar_push (TV_NAME_LOOKUP);
3934 if (TREE_CODE (d1) == IDENTIFIER_NODE)
3936 if (IDENTIFIER_VALUE (d1)
3937 && DECL_TEMPLATE_TEMPLATE_PARM_P (IDENTIFIER_VALUE (d1)))
3938 template = IDENTIFIER_VALUE (d1);
3942 push_decl_namespace (context);
3943 template = lookup_name (d1, /*prefer_type=*/0);
3944 template = maybe_get_template_decl_from_type_decl (template);
3946 pop_decl_namespace ();
3949 context = DECL_CONTEXT (template);
3951 else if (TREE_CODE (d1) == TYPE_DECL && IS_AGGR_TYPE (TREE_TYPE (d1)))
3953 tree type = TREE_TYPE (d1);
3955 /* If we are declaring a constructor, say A<T>::A<T>, we will get
3956 an implicit typename for the second A. Deal with it. */
3957 if (TREE_CODE (type) == TYPENAME_TYPE && TREE_TYPE (type))
3958 type = TREE_TYPE (type);
3960 if (CLASSTYPE_TEMPLATE_INFO (type))
3962 template = CLASSTYPE_TI_TEMPLATE (type);
3963 d1 = DECL_NAME (template);
3966 else if (TREE_CODE (d1) == ENUMERAL_TYPE
3967 || (TYPE_P (d1) && IS_AGGR_TYPE (d1)))
3969 template = TYPE_TI_TEMPLATE (d1);
3970 d1 = DECL_NAME (template);
3972 else if (TREE_CODE (d1) == TEMPLATE_DECL
3973 && TREE_CODE (DECL_TEMPLATE_RESULT (d1)) == TYPE_DECL)
3976 d1 = DECL_NAME (template);
3977 context = DECL_CONTEXT (template);
3980 /* With something like `template <class T> class X class X { ... };'
3981 we could end up with D1 having nothing but an IDENTIFIER_VALUE.
3982 We don't want to do that, but we have to deal with the situation,
3983 so let's give them some syntax errors to chew on instead of a
3984 crash. Alternatively D1 might not be a template type at all. */
3987 if (complain & tf_error)
3988 error ("`%T' is not a template", d1);
3989 POP_TIMEVAR_AND_RETURN (TV_NAME_LOOKUP, error_mark_node);
3992 if (TREE_CODE (template) != TEMPLATE_DECL
3993 /* Make sure it's a user visible template, if it was named by
3995 || ((complain & tf_user) && !DECL_TEMPLATE_PARM_P (template)
3996 && !PRIMARY_TEMPLATE_P (template)))
3998 if (complain & tf_error)
4000 error ("non-template type `%T' used as a template", d1);
4002 cp_error_at ("for template declaration `%D'", in_decl);
4004 POP_TIMEVAR_AND_RETURN (TV_NAME_LOOKUP, error_mark_node);
4007 complain &= ~tf_user;
4009 if (DECL_TEMPLATE_TEMPLATE_PARM_P (template))
4011 /* Create a new TEMPLATE_DECL and TEMPLATE_TEMPLATE_PARM node to store
4012 template arguments */
4017 parmlist = DECL_INNERMOST_TEMPLATE_PARMS (template);
4019 /* Consider an example where a template template parameter declared as
4021 template <class T, class U = std::allocator<T> > class TT
4023 The template parameter level of T and U are one level larger than
4024 of TT. To proper process the default argument of U, say when an
4025 instantiation `TT<int>' is seen, we need to build the full
4026 arguments containing {int} as the innermost level. Outer levels,
4027 available when not appearing as default template argument, can be
4028 obtained from `current_template_args ()'.
4030 Suppose that TT is later substituted with std::vector. The above
4031 instantiation is `TT<int, std::allocator<T> >' with TT at
4032 level 1, and T at level 2, while the template arguments at level 1
4033 becomes {std::vector} and the inner level 2 is {int}. */
4035 if (current_template_parms)
4036 arglist = add_to_template_args (current_template_args (), arglist);
4038 arglist2 = coerce_template_parms (parmlist, arglist, template,
4039 complain, /*require_all_args=*/1);
4040 if (arglist2 == error_mark_node
4041 || (!uses_template_parms (arglist2)
4042 && check_instantiated_args (template, arglist2, complain)))
4043 POP_TIMEVAR_AND_RETURN (TV_NAME_LOOKUP, error_mark_node);
4045 parm = bind_template_template_parm (TREE_TYPE (template), arglist2);
4046 POP_TIMEVAR_AND_RETURN (TV_NAME_LOOKUP, parm);
4050 tree template_type = TREE_TYPE (template);
4053 tree found = NULL_TREE;
4057 int is_partial_instantiation;
4059 gen_tmpl = most_general_template (template);
4060 parmlist = DECL_TEMPLATE_PARMS (gen_tmpl);
4061 parm_depth = TMPL_PARMS_DEPTH (parmlist);
4062 arg_depth = TMPL_ARGS_DEPTH (arglist);
4064 if (arg_depth == 1 && parm_depth > 1)
4066 /* We've been given an incomplete set of template arguments.
4069 template <class T> struct S1 {
4070 template <class U> struct S2 {};
4071 template <class U> struct S2<U*> {};
4074 we will be called with an ARGLIST of `U*', but the
4075 TEMPLATE will be `template <class T> template
4076 <class U> struct S1<T>::S2'. We must fill in the missing
4079 = add_outermost_template_args (TYPE_TI_ARGS (TREE_TYPE (template)),
4081 arg_depth = TMPL_ARGS_DEPTH (arglist);
4084 /* Now we should have enough arguments. */
4085 my_friendly_assert (parm_depth == arg_depth, 0);
4087 /* From here on, we're only interested in the most general
4089 template = gen_tmpl;
4091 /* Calculate the BOUND_ARGS. These will be the args that are
4092 actually tsubst'd into the definition to create the
4096 /* We have multiple levels of arguments to coerce, at once. */
4098 int saved_depth = TMPL_ARGS_DEPTH (arglist);
4100 tree bound_args = make_tree_vec (parm_depth);
4102 for (i = saved_depth,
4103 t = DECL_TEMPLATE_PARMS (template);
4104 i > 0 && t != NULL_TREE;
4105 --i, t = TREE_CHAIN (t))
4107 tree a = coerce_template_parms (TREE_VALUE (t),
4109 complain, /*require_all_args=*/1);
4111 /* Don't process further if one of the levels fails. */
4112 if (a == error_mark_node)
4114 /* Restore the ARGLIST to its full size. */
4115 TREE_VEC_LENGTH (arglist) = saved_depth;
4116 POP_TIMEVAR_AND_RETURN (TV_NAME_LOOKUP, error_mark_node);
4119 SET_TMPL_ARGS_LEVEL (bound_args, i, a);
4121 /* We temporarily reduce the length of the ARGLIST so
4122 that coerce_template_parms will see only the arguments
4123 corresponding to the template parameters it is
4125 TREE_VEC_LENGTH (arglist)--;
4128 /* Restore the ARGLIST to its full size. */
4129 TREE_VEC_LENGTH (arglist) = saved_depth;
4131 arglist = bound_args;
4135 = coerce_template_parms (INNERMOST_TEMPLATE_PARMS (parmlist),
4136 INNERMOST_TEMPLATE_ARGS (arglist),
4138 complain, /*require_all_args=*/1);
4140 if (arglist == error_mark_node
4141 || (!uses_template_parms (INNERMOST_TEMPLATE_ARGS (arglist))
4142 && check_instantiated_args (template,
4143 INNERMOST_TEMPLATE_ARGS (arglist),
4145 /* We were unable to bind the arguments. */
4146 POP_TIMEVAR_AND_RETURN (TV_NAME_LOOKUP, error_mark_node);
4148 /* In the scope of a template class, explicit references to the
4149 template class refer to the type of the template, not any
4150 instantiation of it. For example, in:
4152 template <class T> class C { void f(C<T>); }
4154 the `C<T>' is just the same as `C'. Outside of the
4155 class, however, such a reference is an instantiation. */
4156 if (comp_template_args (TYPE_TI_ARGS (template_type),
4159 found = template_type;
4161 if (!entering_scope && PRIMARY_TEMPLATE_P (template))
4165 for (ctx = current_class_type;
4167 ctx = TYPE_CONTEXT (ctx))
4169 if (TREE_CODE (ctx) == NAMESPACE_DECL)
4171 if (same_type_p (ctx, template_type))
4175 /* We're not in the scope of the class, so the
4176 TEMPLATE_TYPE is not the type we want after all. */
4182 POP_TIMEVAR_AND_RETURN (TV_NAME_LOOKUP, found);
4184 for (tp = &DECL_TEMPLATE_INSTANTIATIONS (template);
4186 tp = &TREE_CHAIN (*tp))
4187 if (comp_template_args (TREE_PURPOSE (*tp), arglist))
4191 /* Use the move-to-front heuristic to speed up future
4193 *tp = TREE_CHAIN (*tp);
4195 = DECL_TEMPLATE_INSTANTIATIONS (template);
4196 DECL_TEMPLATE_INSTANTIATIONS (template) = found;
4198 POP_TIMEVAR_AND_RETURN (TV_NAME_LOOKUP, TREE_VALUE (found));
4201 /* This type is a "partial instantiation" if any of the template
4202 arguments still involve template parameters. Note that we set
4203 IS_PARTIAL_INSTANTIATION for partial specializations as
4205 is_partial_instantiation = uses_template_parms (arglist);
4207 if (!is_partial_instantiation
4208 && !PRIMARY_TEMPLATE_P (template)
4209 && TREE_CODE (CP_DECL_CONTEXT (template)) == NAMESPACE_DECL)
4211 found = xref_tag_from_type (TREE_TYPE (template),
4212 DECL_NAME (template),
4214 POP_TIMEVAR_AND_RETURN (TV_NAME_LOOKUP, found);
4217 context = tsubst (DECL_CONTEXT (template), arglist,
4220 context = global_namespace;
4222 /* Create the type. */
4223 if (TREE_CODE (template_type) == ENUMERAL_TYPE)
4225 if (!is_partial_instantiation)
4227 set_current_access_from_decl (TYPE_NAME (template_type));
4228 t = start_enum (TYPE_IDENTIFIER (template_type));
4231 /* We don't want to call start_enum for this type, since
4232 the values for the enumeration constants may involve
4233 template parameters. And, no one should be interested
4234 in the enumeration constants for such a type. */
4235 t = make_node (ENUMERAL_TYPE);
4239 t = make_aggr_type (TREE_CODE (template_type));
4240 CLASSTYPE_DECLARED_CLASS (t)
4241 = CLASSTYPE_DECLARED_CLASS (template_type);
4242 SET_CLASSTYPE_IMPLICIT_INSTANTIATION (t);
4243 TYPE_FOR_JAVA (t) = TYPE_FOR_JAVA (template_type);
4245 /* A local class. Make sure the decl gets registered properly. */
4246 if (context == current_function_decl)
4247 pushtag (DECL_NAME (template), t, 0);
4250 /* If we called start_enum or pushtag above, this information
4251 will already be set up. */
4254 TYPE_CONTEXT (t) = FROB_CONTEXT (context);
4256 type_decl = create_implicit_typedef (DECL_NAME (template), t);
4257 DECL_CONTEXT (type_decl) = TYPE_CONTEXT (t);
4258 TYPE_STUB_DECL (t) = type_decl;
4259 DECL_SOURCE_LOCATION (type_decl)
4260 = DECL_SOURCE_LOCATION (TYPE_STUB_DECL (template_type));
4263 type_decl = TYPE_NAME (t);
4265 TREE_PRIVATE (type_decl)
4266 = TREE_PRIVATE (TYPE_STUB_DECL (template_type));
4267 TREE_PROTECTED (type_decl)
4268 = TREE_PROTECTED (TYPE_STUB_DECL (template_type));
4270 /* Set up the template information. We have to figure out which
4271 template is the immediate parent if this is a full
4273 if (parm_depth == 1 || is_partial_instantiation
4274 || !PRIMARY_TEMPLATE_P (template))
4275 /* This case is easy; there are no member templates involved. */
4279 /* This is a full instantiation of a member template. Look
4280 for a partial instantiation of which this is an instance. */
4282 for (found = DECL_TEMPLATE_INSTANTIATIONS (template);
4283 found; found = TREE_CHAIN (found))
4286 tree tmpl = CLASSTYPE_TI_TEMPLATE (TREE_VALUE (found));
4288 /* We only want partial instantiations, here, not
4289 specializations or full instantiations. */
4290 if (CLASSTYPE_TEMPLATE_SPECIALIZATION (TREE_VALUE (found))
4291 || !uses_template_parms (TREE_VALUE (found)))
4294 /* Temporarily reduce by one the number of levels in the
4295 ARGLIST and in FOUND so as to avoid comparing the
4296 last set of arguments. */
4297 TREE_VEC_LENGTH (arglist)--;
4298 TREE_VEC_LENGTH (TREE_PURPOSE (found)) --;
4300 /* See if the arguments match. If they do, then TMPL is
4301 the partial instantiation we want. */
4302 success = comp_template_args (TREE_PURPOSE (found), arglist);
4304 /* Restore the argument vectors to their full size. */
4305 TREE_VEC_LENGTH (arglist)++;
4306 TREE_VEC_LENGTH (TREE_PURPOSE (found))++;
4317 /* There was no partial instantiation. This happens
4318 where C<T> is a member template of A<T> and it's used
4321 template <typename T> struct B { A<T>::C<int> m; };
4324 Create the partial instantiation.
4326 TREE_VEC_LENGTH (arglist)--;
4327 found = tsubst (template, arglist, complain, NULL_TREE);
4328 TREE_VEC_LENGTH (arglist)++;
4332 SET_TYPE_TEMPLATE_INFO (t, tree_cons (found, arglist, NULL_TREE));
4333 DECL_TEMPLATE_INSTANTIATIONS (template)
4334 = tree_cons (arglist, t,
4335 DECL_TEMPLATE_INSTANTIATIONS (template));
4337 if (TREE_CODE (t) == ENUMERAL_TYPE
4338 && !is_partial_instantiation)
4339 /* Now that the type has been registered on the instantiations
4340 list, we set up the enumerators. Because the enumeration
4341 constants may involve the enumeration type itself, we make
4342 sure to register the type first, and then create the
4343 constants. That way, doing tsubst_expr for the enumeration
4344 constants won't result in recursive calls here; we'll find
4345 the instantiation and exit above. */
4346 tsubst_enum (template_type, t, arglist);
4348 /* Reset the name of the type, now that CLASSTYPE_TEMPLATE_INFO
4350 if (TREE_CODE (t) != ENUMERAL_TYPE)
4351 DECL_NAME (type_decl) = classtype_mangled_name (t);
4352 if (!is_partial_instantiation)
4354 /* For backwards compatibility; code that uses
4355 -fexternal-templates expects looking up a template to
4356 instantiate it. I think DDD still relies on this.
4357 (jason 8/20/1998) */
4358 if (TREE_CODE (t) != ENUMERAL_TYPE
4359 && flag_external_templates
4360 && CLASSTYPE_INTERFACE_KNOWN (TREE_TYPE (template))
4361 && ! CLASSTYPE_INTERFACE_ONLY (TREE_TYPE (template)))
4362 add_pending_template (t);
4365 /* If the type makes use of template parameters, the
4366 code that generates debugging information will crash. */
4367 DECL_IGNORED_P (TYPE_STUB_DECL (t)) = 1;
4369 POP_TIMEVAR_AND_RETURN (TV_NAME_LOOKUP, t);
4371 timevar_pop (TV_NAME_LOOKUP);
4381 /* Called from for_each_template_parm via walk_tree. */
4384 for_each_template_parm_r (tree* tp, int* walk_subtrees, void* d)
4387 struct pair_fn_data *pfd = (struct pair_fn_data *) d;
4388 tree_fn_t fn = pfd->fn;
4389 void *data = pfd->data;
4392 /* If we have already visited this tree, there's no need to walk
4393 subtrees. Otherwise, add it to the visited table. */
4394 slot = htab_find_slot (pfd->visited, *tp, INSERT);
4403 && for_each_template_parm (TYPE_CONTEXT (t), fn, data, pfd->visited))
4404 return error_mark_node;
4406 switch (TREE_CODE (t))
4409 if (TYPE_PTRMEMFUNC_P (t))
4415 if (!TYPE_TEMPLATE_INFO (t))
4417 else if (for_each_template_parm (TREE_VALUE (TYPE_TEMPLATE_INFO (t)),
4418 fn, data, pfd->visited))
4419 return error_mark_node;
4423 /* Since we're not going to walk subtrees, we have to do this
4425 if (for_each_template_parm (TYPE_METHOD_BASETYPE (t), fn, data,
4427 return error_mark_node;
4431 /* Check the return type. */
4432 if (for_each_template_parm (TREE_TYPE (t), fn, data, pfd->visited))
4433 return error_mark_node;
4435 /* Check the parameter types. Since default arguments are not
4436 instantiated until they are needed, the TYPE_ARG_TYPES may
4437 contain expressions that involve template parameters. But,
4438 no-one should be looking at them yet. And, once they're
4439 instantiated, they don't contain template parameters, so
4440 there's no point in looking at them then, either. */
4444 for (parm = TYPE_ARG_TYPES (t); parm; parm = TREE_CHAIN (parm))
4445 if (for_each_template_parm (TREE_VALUE (parm), fn, data,
4447 return error_mark_node;
4449 /* Since we've already handled the TYPE_ARG_TYPES, we don't
4450 want walk_tree walking into them itself. */
4456 if (for_each_template_parm (TYPE_FIELDS (t), fn, data,
4458 return error_mark_node;
4463 if (DECL_LANG_SPECIFIC (t) && DECL_TEMPLATE_INFO (t)
4464 && for_each_template_parm (DECL_TI_ARGS (t), fn, data,
4466 return error_mark_node;
4471 if (TREE_CODE (t) == CONST_DECL && DECL_TEMPLATE_PARM_P (t)
4472 && for_each_template_parm (DECL_INITIAL (t), fn, data,
4474 return error_mark_node;
4475 if (DECL_CONTEXT (t)
4476 && for_each_template_parm (DECL_CONTEXT (t), fn, data,
4478 return error_mark_node;
4481 case BOUND_TEMPLATE_TEMPLATE_PARM:
4482 /* Record template parameters such as `T' inside `TT<T>'. */
4483 if (for_each_template_parm (TYPE_TI_ARGS (t), fn, data, pfd->visited))
4484 return error_mark_node;
4487 case TEMPLATE_TEMPLATE_PARM:
4488 case TEMPLATE_TYPE_PARM:
4489 case TEMPLATE_PARM_INDEX:
4490 if (fn && (*fn)(t, data))
4491 return error_mark_node;
4493 return error_mark_node;
4497 /* A template template parameter is encountered */
4498 if (DECL_TEMPLATE_TEMPLATE_PARM_P (t)
4499 && for_each_template_parm (TREE_TYPE (t), fn, data, pfd->visited))
4500 return error_mark_node;
4502 /* Already substituted template template parameter */
4508 || for_each_template_parm (TYPENAME_TYPE_FULLNAME (t), fn,
4509 data, pfd->visited))
4510 return error_mark_node;
4514 if (TREE_TYPE (t) && TYPE_PTRMEMFUNC_P (TREE_TYPE (t))
4515 && for_each_template_parm (TYPE_PTRMEMFUNC_FN_TYPE
4516 (TREE_TYPE (t)), fn, data,
4518 return error_mark_node;
4523 /* If there's no type, then this thing must be some expression
4524 involving template parameters. */
4525 if (!fn && !TREE_TYPE (t))
4526 return error_mark_node;
4531 case REINTERPRET_CAST_EXPR:
4532 case CONST_CAST_EXPR:
4533 case STATIC_CAST_EXPR:
4534 case DYNAMIC_CAST_EXPR:
4538 case PSEUDO_DTOR_EXPR:
4540 return error_mark_node;
4544 /* If we do not handle this case specially, we end up walking
4545 the BINFO hierarchy, which is circular, and therefore
4546 confuses walk_tree. */
4548 if (for_each_template_parm (BASELINK_FUNCTIONS (*tp), fn, data,
4550 return error_mark_node;
4557 /* We didn't find any template parameters we liked. */
4561 /* For each TEMPLATE_TYPE_PARM, TEMPLATE_TEMPLATE_PARM,
4562 BOUND_TEMPLATE_TEMPLATE_PARM or TEMPLATE_PARM_INDEX in T,
4563 call FN with the parameter and the DATA.
4564 If FN returns nonzero, the iteration is terminated, and
4565 for_each_template_parm returns 1. Otherwise, the iteration
4566 continues. If FN never returns a nonzero value, the value
4567 returned by for_each_template_parm is 0. If FN is NULL, it is
4568 considered to be the function which always returns 1. */
4571 for_each_template_parm (tree t, tree_fn_t fn, void* data, htab_t visited)
4573 struct pair_fn_data pfd;
4580 /* Walk the tree. (Conceptually, we would like to walk without
4581 duplicates, but for_each_template_parm_r recursively calls
4582 for_each_template_parm, so we would need to reorganize a fair
4583 bit to use walk_tree_without_duplicates, so we keep our own
4586 pfd.visited = visited;
4588 pfd.visited = htab_create (37, htab_hash_pointer, htab_eq_pointer,
4590 result = walk_tree (&t,
4591 for_each_template_parm_r,
4597 htab_delete (pfd.visited);
4603 uses_template_parms (tree t)
4605 return for_each_template_parm (t, 0, 0, NULL);
4608 static int tinst_depth;
4609 extern int max_tinst_depth;
4610 #ifdef GATHER_STATISTICS
4613 static int tinst_level_tick;
4614 static int last_template_error_tick;
4616 /* We're starting to instantiate D; record the template instantiation context
4617 for diagnostics and to restore it later. */
4620 push_tinst_level (tree d)
4624 if (tinst_depth >= max_tinst_depth)
4626 /* If the instantiation in question still has unbound template parms,
4627 we don't really care if we can't instantiate it, so just return.
4628 This happens with base instantiation for implicit `typename'. */
4629 if (uses_template_parms (d))
4632 last_template_error_tick = tinst_level_tick;
4633 error ("template instantiation depth exceeds maximum of %d (use -ftemplate-depth-NN to increase the maximum) instantiating `%D'",
4634 max_tinst_depth, d);
4636 print_instantiation_context ();
4641 new = build_expr_wfl (d, input_filename, input_line, 0);
4642 TREE_CHAIN (new) = current_tinst_level;
4643 current_tinst_level = new;
4646 #ifdef GATHER_STATISTICS
4647 if (tinst_depth > depth_reached)
4648 depth_reached = tinst_depth;
4655 /* We're done instantiating this template; return to the instantiation
4659 pop_tinst_level (void)
4661 tree old = current_tinst_level;
4663 /* Restore the filename and line number stashed away when we started
4664 this instantiation. */
4665 input_line = TINST_LINE (old);
4666 input_filename = TINST_FILE (old);
4667 extract_interface_info ();
4669 current_tinst_level = TREE_CHAIN (old);
4674 /* We're instantiating a deferred template; restore the template
4675 instantiation context in which the instantiation was requested, which
4676 is one step out from LEVEL. */
4679 reopen_tinst_level (tree level)
4684 for (t = level; t; t = TREE_CHAIN (t))
4687 current_tinst_level = level;
4691 /* Return the outermost template instantiation context, for use with
4692 -falt-external-templates. */
4695 tinst_for_decl (void)
4697 tree p = current_tinst_level;
4700 for (; TREE_CHAIN (p) ; p = TREE_CHAIN (p))
4705 /* DECL is a friend FUNCTION_DECL or TEMPLATE_DECL. ARGS is the
4706 vector of template arguments, as for tsubst.
4708 Returns an appropriate tsubst'd friend declaration. */
4711 tsubst_friend_function (tree decl, tree args)
4714 location_t saved_loc = input_location;
4716 input_location = DECL_SOURCE_LOCATION (decl);
4718 if (TREE_CODE (decl) == FUNCTION_DECL
4719 && DECL_TEMPLATE_INSTANTIATION (decl)
4720 && TREE_CODE (DECL_TI_TEMPLATE (decl)) != TEMPLATE_DECL)
4721 /* This was a friend declared with an explicit template
4722 argument list, e.g.:
4726 to indicate that f was a template instantiation, not a new
4727 function declaration. Now, we have to figure out what
4728 instantiation of what template. */
4730 tree template_id, arglist, fns;
4733 tree ns = decl_namespace_context (TYPE_MAIN_DECL (current_class_type));
4735 /* Friend functions are looked up in the containing namespace scope.
4736 We must enter that scope, to avoid finding member functions of the
4737 current cless with same name. */
4738 push_nested_namespace (ns);
4739 fns = tsubst_expr (DECL_TI_TEMPLATE (decl), args,
4740 tf_error | tf_warning, NULL_TREE);
4741 pop_nested_namespace (ns);
4742 arglist = tsubst (DECL_TI_ARGS (decl), args,
4743 tf_error | tf_warning, NULL_TREE);
4744 template_id = lookup_template_function (fns, arglist);
4746 new_friend = tsubst (decl, args, tf_error | tf_warning, NULL_TREE);
4747 tmpl = determine_specialization (template_id, new_friend,
4749 /*need_member_template=*/0);
4750 new_friend = instantiate_template (tmpl, new_args, tf_error);
4754 new_friend = tsubst (decl, args, tf_error | tf_warning, NULL_TREE);
4756 /* The NEW_FRIEND will look like an instantiation, to the
4757 compiler, but is not an instantiation from the point of view of
4758 the language. For example, we might have had:
4760 template <class T> struct S {
4761 template <class U> friend void f(T, U);
4764 Then, in S<int>, template <class U> void f(int, U) is not an
4765 instantiation of anything. */
4766 DECL_USE_TEMPLATE (new_friend) = 0;
4767 if (TREE_CODE (decl) == TEMPLATE_DECL)
4769 DECL_USE_TEMPLATE (DECL_TEMPLATE_RESULT (new_friend)) = 0;
4770 DECL_SAVED_TREE (DECL_TEMPLATE_RESULT (new_friend))
4771 = DECL_SAVED_TREE (DECL_TEMPLATE_RESULT (decl));
4774 /* The mangled name for the NEW_FRIEND is incorrect. The function
4775 is not a template instantiation and should not be mangled like
4776 one. Therefore, we forget the mangling here; we'll recompute it
4777 later if we need it. */
4778 if (TREE_CODE (new_friend) != TEMPLATE_DECL)
4780 SET_DECL_RTL (new_friend, NULL_RTX);
4781 SET_DECL_ASSEMBLER_NAME (new_friend, NULL_TREE);
4784 if (DECL_NAMESPACE_SCOPE_P (new_friend))
4787 tree new_friend_template_info;
4788 tree new_friend_result_template_info;
4790 int new_friend_is_defn;
4792 /* We must save some information from NEW_FRIEND before calling
4793 duplicate decls since that function will free NEW_FRIEND if
4795 new_friend_template_info = DECL_TEMPLATE_INFO (new_friend);
4796 if (TREE_CODE (new_friend) == TEMPLATE_DECL)
4798 /* This declaration is a `primary' template. */
4799 DECL_PRIMARY_TEMPLATE (new_friend) = new_friend;
4802 = DECL_INITIAL (DECL_TEMPLATE_RESULT (new_friend)) != NULL_TREE;
4803 new_friend_result_template_info
4804 = DECL_TEMPLATE_INFO (DECL_TEMPLATE_RESULT (new_friend));
4808 new_friend_is_defn = DECL_INITIAL (new_friend) != NULL_TREE;
4809 new_friend_result_template_info = NULL_TREE;
4812 /* Inside pushdecl_namespace_level, we will push into the
4813 current namespace. However, the friend function should go
4814 into the namespace of the template. */
4815 ns = decl_namespace_context (new_friend);
4816 push_nested_namespace (ns);
4817 old_decl = pushdecl_namespace_level (new_friend);
4818 pop_nested_namespace (ns);
4820 if (old_decl != new_friend)
4822 /* This new friend declaration matched an existing
4823 declaration. For example, given:
4825 template <class T> void f(T);
4826 template <class U> class C {
4827 template <class T> friend void f(T) {}
4830 the friend declaration actually provides the definition
4831 of `f', once C has been instantiated for some type. So,
4832 old_decl will be the out-of-class template declaration,
4833 while new_friend is the in-class definition.
4835 But, if `f' was called before this point, the
4836 instantiation of `f' will have DECL_TI_ARGS corresponding
4837 to `T' but not to `U', references to which might appear
4838 in the definition of `f'. Previously, the most general
4839 template for an instantiation of `f' was the out-of-class
4840 version; now it is the in-class version. Therefore, we
4841 run through all specialization of `f', adding to their
4842 DECL_TI_ARGS appropriately. In particular, they need a
4843 new set of outer arguments, corresponding to the
4844 arguments for this class instantiation.
4846 The same situation can arise with something like this:
4849 template <class T> class C {
4853 when `C<int>' is instantiated. Now, `f(int)' is defined
4856 if (!new_friend_is_defn)
4857 /* On the other hand, if the in-class declaration does
4858 *not* provide a definition, then we don't want to alter
4859 existing definitions. We can just leave everything
4864 /* Overwrite whatever template info was there before, if
4865 any, with the new template information pertaining to
4867 DECL_TEMPLATE_INFO (old_decl) = new_friend_template_info;
4869 if (TREE_CODE (old_decl) != TEMPLATE_DECL)
4870 reregister_specialization (new_friend,
4871 most_general_template (old_decl),
4876 tree new_friend_args;
4878 DECL_TEMPLATE_INFO (DECL_TEMPLATE_RESULT (old_decl))
4879 = new_friend_result_template_info;
4881 new_friend_args = TI_ARGS (new_friend_template_info);
4882 for (t = DECL_TEMPLATE_SPECIALIZATIONS (old_decl);
4886 tree spec = TREE_VALUE (t);
4889 = add_outermost_template_args (new_friend_args,
4890 DECL_TI_ARGS (spec));
4893 /* Now, since specializations are always supposed to
4894 hang off of the most general template, we must move
4896 t = most_general_template (old_decl);
4899 DECL_TEMPLATE_SPECIALIZATIONS (t)
4900 = chainon (DECL_TEMPLATE_SPECIALIZATIONS (t),
4901 DECL_TEMPLATE_SPECIALIZATIONS (old_decl));
4902 DECL_TEMPLATE_SPECIALIZATIONS (old_decl) = NULL_TREE;
4907 /* The information from NEW_FRIEND has been merged into OLD_DECL
4908 by duplicate_decls. */
4909 new_friend = old_decl;
4912 else if (COMPLETE_TYPE_P (DECL_CONTEXT (new_friend)))
4914 /* Check to see that the declaration is really present, and,
4915 possibly obtain an improved declaration. */
4916 tree fn = check_classfn (DECL_CONTEXT (new_friend),
4924 input_location = saved_loc;
4928 /* FRIEND_TMPL is a friend TEMPLATE_DECL. ARGS is the vector of
4929 template arguments, as for tsubst.
4931 Returns an appropriate tsubst'd friend type or error_mark_node on
4935 tsubst_friend_class (tree friend_tmpl, tree args)
4941 context = DECL_CONTEXT (friend_tmpl);
4945 if (TREE_CODE (context) == NAMESPACE_DECL)
4946 push_nested_namespace (context);
4948 push_nested_class (tsubst (context, args, tf_none, NULL_TREE));
4951 /* First, we look for a class template. */
4952 tmpl = lookup_name (DECL_NAME (friend_tmpl), /*prefer_type=*/0);
4954 /* But, if we don't find one, it might be because we're in a
4955 situation like this:
4963 Here, in the scope of (say) S<int>, `S' is bound to a TYPE_DECL
4964 for `S<int>', not the TEMPLATE_DECL. */
4965 if (!tmpl || !DECL_CLASS_TEMPLATE_P (tmpl))
4967 tmpl = lookup_name (DECL_NAME (friend_tmpl), /*prefer_type=*/1);
4968 tmpl = maybe_get_template_decl_from_type_decl (tmpl);
4971 if (tmpl && DECL_CLASS_TEMPLATE_P (tmpl))
4973 /* The friend template has already been declared. Just
4974 check to see that the declarations match, and install any new
4975 default parameters. We must tsubst the default parameters,
4976 of course. We only need the innermost template parameters
4977 because that is all that redeclare_class_template will look
4979 if (TMPL_PARMS_DEPTH (DECL_TEMPLATE_PARMS (friend_tmpl))
4980 > TMPL_ARGS_DEPTH (args))
4983 parms = tsubst_template_parms (DECL_TEMPLATE_PARMS (friend_tmpl),
4984 args, tf_error | tf_warning);
4985 redeclare_class_template (TREE_TYPE (tmpl), parms);
4988 friend_type = TREE_TYPE (tmpl);
4992 /* The friend template has not already been declared. In this
4993 case, the instantiation of the template class will cause the
4994 injection of this template into the global scope. */
4995 tmpl = tsubst (friend_tmpl, args, tf_error | tf_warning, NULL_TREE);
4997 /* The new TMPL is not an instantiation of anything, so we
4998 forget its origins. We don't reset CLASSTYPE_TI_TEMPLATE for
4999 the new type because that is supposed to be the corresponding
5000 template decl, i.e., TMPL. */
5001 DECL_USE_TEMPLATE (tmpl) = 0;
5002 DECL_TEMPLATE_INFO (tmpl) = NULL_TREE;
5003 CLASSTYPE_USE_TEMPLATE (TREE_TYPE (tmpl)) = 0;
5004 CLASSTYPE_TI_ARGS (TREE_TYPE (tmpl))
5005 = INNERMOST_TEMPLATE_ARGS (CLASSTYPE_TI_ARGS (TREE_TYPE (tmpl)));
5007 /* Inject this template into the global scope. */
5008 friend_type = TREE_TYPE (pushdecl_top_level (tmpl));
5013 if (TREE_CODE (context) == NAMESPACE_DECL)
5014 pop_nested_namespace (context);
5016 pop_nested_class ();
5022 /* Returns zero if TYPE cannot be completed later due to circularity.
5023 Otherwise returns one. */
5026 can_complete_type_without_circularity (tree type)
5028 if (type == NULL_TREE || type == error_mark_node)
5030 else if (COMPLETE_TYPE_P (type))
5032 else if (TREE_CODE (type) == ARRAY_TYPE && TYPE_DOMAIN (type))
5033 return can_complete_type_without_circularity (TREE_TYPE (type));
5034 else if (CLASS_TYPE_P (type)
5035 && TYPE_BEING_DEFINED (TYPE_MAIN_VARIANT (type)))
5042 instantiate_class_template (tree type)
5044 tree template, args, pattern, t, member;
5048 if (type == error_mark_node)
5049 return error_mark_node;
5051 if (TYPE_BEING_DEFINED (type)
5052 || COMPLETE_TYPE_P (type)
5053 || dependent_type_p (type))
5056 /* Figure out which template is being instantiated. */
5057 template = most_general_template (CLASSTYPE_TI_TEMPLATE (type));
5058 my_friendly_assert (TREE_CODE (template) == TEMPLATE_DECL, 279);
5060 /* Figure out which arguments are being used to do the
5062 args = CLASSTYPE_TI_ARGS (type);
5064 /* Determine what specialization of the original template to
5066 t = most_specialized_class (template, args);
5067 if (t == error_mark_node)
5069 const char *str = "candidates are:";
5070 error ("ambiguous class template instantiation for `%#T'", type);
5071 for (t = DECL_TEMPLATE_SPECIALIZATIONS (template); t;
5074 if (get_class_bindings (TREE_VALUE (t), TREE_PURPOSE (t), args))
5076 cp_error_at ("%s %+#T", str, TREE_TYPE (t));
5080 TYPE_BEING_DEFINED (type) = 1;
5081 return error_mark_node;
5085 pattern = TREE_TYPE (t);
5087 pattern = TREE_TYPE (template);
5089 /* If the template we're instantiating is incomplete, then clearly
5090 there's nothing we can do. */
5091 if (!COMPLETE_TYPE_P (pattern))
5094 /* If we've recursively instantiated too many templates, stop. */
5095 if (! push_tinst_level (type))
5098 /* Now we're really doing the instantiation. Mark the type as in
5099 the process of being defined. */
5100 TYPE_BEING_DEFINED (type) = 1;
5102 /* We may be in the middle of deferred access check. Disable
5104 push_deferring_access_checks (dk_no_deferred);
5106 maybe_push_to_top_level (uses_template_parms (type));
5110 /* This TYPE is actually an instantiation of a partial
5111 specialization. We replace the innermost set of ARGS with
5112 the arguments appropriate for substitution. For example,
5115 template <class T> struct S {};
5116 template <class T> struct S<T*> {};
5118 and supposing that we are instantiating S<int*>, ARGS will
5119 present be {int*} but we need {int}. */
5121 = get_class_bindings (TREE_VALUE (t), TREE_PURPOSE (t),
5124 /* If there were multiple levels in ARGS, replacing the
5125 innermost level would alter CLASSTYPE_TI_ARGS, which we don't
5126 want, so we make a copy first. */
5127 if (TMPL_ARGS_HAVE_MULTIPLE_LEVELS (args))
5129 args = copy_node (args);
5130 SET_TMPL_ARGS_LEVEL (args, TMPL_ARGS_DEPTH (args), inner_args);
5136 if (flag_external_templates)
5138 if (flag_alt_external_templates)
5140 CLASSTYPE_INTERFACE_ONLY (type) = interface_only;
5141 SET_CLASSTYPE_INTERFACE_UNKNOWN_X (type, interface_unknown);
5145 CLASSTYPE_INTERFACE_ONLY (type) = CLASSTYPE_INTERFACE_ONLY (pattern);
5146 SET_CLASSTYPE_INTERFACE_UNKNOWN_X
5147 (type, CLASSTYPE_INTERFACE_UNKNOWN (pattern));
5152 SET_CLASSTYPE_INTERFACE_UNKNOWN (type);
5155 /* Set the input location to the template definition. This is needed
5156 if tsubsting causes an error. */
5157 input_location = DECL_SOURCE_LOCATION (TYPE_NAME (pattern));
5159 TYPE_HAS_CONSTRUCTOR (type) = TYPE_HAS_CONSTRUCTOR (pattern);
5160 TYPE_HAS_DESTRUCTOR (type) = TYPE_HAS_DESTRUCTOR (pattern);
5161 TYPE_HAS_NEW_OPERATOR (type) = TYPE_HAS_NEW_OPERATOR (pattern);
5162 TYPE_HAS_ARRAY_NEW_OPERATOR (type) = TYPE_HAS_ARRAY_NEW_OPERATOR (pattern);
5163 TYPE_GETS_DELETE (type) = TYPE_GETS_DELETE (pattern);
5164 TYPE_HAS_ASSIGN_REF (type) = TYPE_HAS_ASSIGN_REF (pattern);
5165 TYPE_HAS_CONST_ASSIGN_REF (type) = TYPE_HAS_CONST_ASSIGN_REF (pattern);
5166 TYPE_HAS_ABSTRACT_ASSIGN_REF (type) = TYPE_HAS_ABSTRACT_ASSIGN_REF (pattern);
5167 TYPE_HAS_INIT_REF (type) = TYPE_HAS_INIT_REF (pattern);
5168 TYPE_HAS_CONST_INIT_REF (type) = TYPE_HAS_CONST_INIT_REF (pattern);
5169 TYPE_HAS_DEFAULT_CONSTRUCTOR (type) = TYPE_HAS_DEFAULT_CONSTRUCTOR (pattern);
5170 TYPE_HAS_CONVERSION (type) = TYPE_HAS_CONVERSION (pattern);
5171 TYPE_BASE_CONVS_MAY_REQUIRE_CODE_P (type)
5172 = TYPE_BASE_CONVS_MAY_REQUIRE_CODE_P (pattern);
5173 TYPE_USES_MULTIPLE_INHERITANCE (type)
5174 = TYPE_USES_MULTIPLE_INHERITANCE (pattern);
5175 TYPE_USES_VIRTUAL_BASECLASSES (type)
5176 = TYPE_USES_VIRTUAL_BASECLASSES (pattern);
5177 TYPE_PACKED (type) = TYPE_PACKED (pattern);
5178 TYPE_ALIGN (type) = TYPE_ALIGN (pattern);
5179 TYPE_USER_ALIGN (type) = TYPE_USER_ALIGN (pattern);
5180 TYPE_FOR_JAVA (type) = TYPE_FOR_JAVA (pattern); /* For libjava's JArray<T> */
5181 if (ANON_AGGR_TYPE_P (pattern))
5182 SET_ANON_AGGR_TYPE_P (type);
5184 pbinfo = TYPE_BINFO (pattern);
5186 if (BINFO_BASETYPES (pbinfo))
5188 tree base_list = NULL_TREE;
5189 tree pbases = BINFO_BASETYPES (pbinfo);
5190 tree paccesses = BINFO_BASEACCESSES (pbinfo);
5191 tree context = TYPE_CONTEXT (type);
5194 /* We must enter the scope containing the type, as that is where
5195 the accessibility of types named in dependent bases are
5197 push_scope (context ? context : global_namespace);
5199 /* Substitute into each of the bases to determine the actual
5201 for (i = 0; i < TREE_VEC_LENGTH (pbases); ++i)
5207 pbase = TREE_VEC_ELT (pbases, i);
5208 access = TREE_VEC_ELT (paccesses, i);
5210 /* Substitute to figure out the base class. */
5211 base = tsubst (BINFO_TYPE (pbase), args, tf_error, NULL_TREE);
5212 if (base == error_mark_node)
5215 base_list = tree_cons (access, base, base_list);
5216 TREE_VIA_VIRTUAL (base_list) = TREE_VIA_VIRTUAL (pbase);
5219 /* The list is now in reverse order; correct that. */
5220 base_list = nreverse (base_list);
5222 /* Now call xref_basetypes to set up all the base-class
5224 xref_basetypes (type, base_list);
5226 pop_scope (context ? context : global_namespace);
5229 /* Now that our base classes are set up, enter the scope of the
5230 class, so that name lookups into base classes, etc. will work
5231 correctly. This is precisely analogous to what we do in
5232 begin_class_definition when defining an ordinary non-template
5236 /* Now members are processed in the order of declaration. */
5237 for (member = CLASSTYPE_DECL_LIST (pattern);
5238 member; member = TREE_CHAIN (member))
5240 tree t = TREE_VALUE (member);
5242 if (TREE_PURPOSE (member))
5246 /* Build new CLASSTYPE_NESTED_UTDS. */
5249 tree name = TYPE_IDENTIFIER (tag);
5252 newtag = tsubst (tag, args, tf_error, NULL_TREE);
5253 my_friendly_assert (newtag != error_mark_node, 20010206);
5254 if (TREE_CODE (newtag) != ENUMERAL_TYPE)
5256 if (TYPE_LANG_SPECIFIC (tag) && CLASSTYPE_IS_TEMPLATE (tag))
5257 /* Unfortunately, lookup_template_class sets
5258 CLASSTYPE_IMPLICIT_INSTANTIATION for a partial
5259 instantiation (i.e., for the type of a member
5260 template class nested within a template class.)
5261 This behavior is required for
5262 maybe_process_partial_specialization to work
5263 correctly, but is not accurate in this case;
5264 the TAG is not an instantiation of anything.
5265 (The corresponding TEMPLATE_DECL is an
5266 instantiation, but the TYPE is not.) */
5267 CLASSTYPE_USE_TEMPLATE (newtag) = 0;
5269 /* Now, we call pushtag to put this NEWTAG into the scope of
5270 TYPE. We first set up the IDENTIFIER_TYPE_VALUE to avoid
5271 pushtag calling push_template_decl. We don't have to do
5272 this for enums because it will already have been done in
5275 SET_IDENTIFIER_TYPE_VALUE (name, newtag);
5276 pushtag (name, newtag, /*globalize=*/0);
5279 else if (TREE_CODE (t) == FUNCTION_DECL
5280 || DECL_FUNCTION_TEMPLATE_P (t))
5282 /* Build new TYPE_METHODS. */
5285 if (TREE_CODE (t) == TEMPLATE_DECL)
5286 processing_template_decl++;
5287 r = tsubst (t, args, tf_error, NULL_TREE);
5288 if (TREE_CODE (t) == TEMPLATE_DECL)
5289 processing_template_decl--;
5290 set_current_access_from_decl (r);
5291 grok_special_member_properties (r);
5292 finish_member_declaration (r);
5296 /* Build new TYPE_FIELDS. */
5298 if (TREE_CODE (t) != CONST_DECL)
5302 /* The the file and line for this declaration, to
5303 assist in error message reporting. Since we
5304 called push_tinst_level above, we don't need to
5306 input_location = DECL_SOURCE_LOCATION (t);
5308 if (TREE_CODE (t) == TEMPLATE_DECL)
5309 processing_template_decl++;
5310 r = tsubst (t, args, tf_error | tf_warning, NULL_TREE);
5311 if (TREE_CODE (t) == TEMPLATE_DECL)
5312 processing_template_decl--;
5313 if (TREE_CODE (r) == VAR_DECL)
5317 if (DECL_INITIALIZED_IN_CLASS_P (r))
5318 init = tsubst_expr (DECL_INITIAL (t), args,
5319 tf_error | tf_warning, NULL_TREE);
5323 finish_static_data_member_decl
5324 (r, init, /*asmspec_tree=*/NULL_TREE, /*flags=*/0);
5326 if (DECL_INITIALIZED_IN_CLASS_P (r))
5327 check_static_variable_definition (r, TREE_TYPE (r));
5329 else if (TREE_CODE (r) == FIELD_DECL)
5331 /* Determine whether R has a valid type and can be
5332 completed later. If R is invalid, then it is
5333 replaced by error_mark_node so that it will not be
5334 added to TYPE_FIELDS. */
5335 tree rtype = TREE_TYPE (r);
5336 if (can_complete_type_without_circularity (rtype))
5337 complete_type (rtype);
5339 if (!COMPLETE_TYPE_P (rtype))
5341 cxx_incomplete_type_error (r, rtype);
5342 r = error_mark_node;
5346 /* If it is a TYPE_DECL for a class-scoped ENUMERAL_TYPE,
5347 such a thing will already have been added to the field
5348 list by tsubst_enum in finish_member_declaration in the
5349 CLASSTYPE_NESTED_UTDS case above. */
5350 if (!(TREE_CODE (r) == TYPE_DECL
5351 && TREE_CODE (TREE_TYPE (r)) == ENUMERAL_TYPE
5352 && DECL_ARTIFICIAL (r)))
5354 set_current_access_from_decl (r);
5355 finish_member_declaration (r);
5362 if (TYPE_P (t) || DECL_CLASS_TEMPLATE_P (t))
5364 /* Build new CLASSTYPE_FRIEND_CLASSES. */
5366 tree friend_type = t;
5367 tree new_friend_type;
5369 if (TREE_CODE (friend_type) == TEMPLATE_DECL)
5370 new_friend_type = tsubst_friend_class (friend_type, args);
5371 else if (uses_template_parms (friend_type))
5372 new_friend_type = tsubst (friend_type, args,
5373 tf_error | tf_warning, NULL_TREE);
5374 else if (CLASSTYPE_USE_TEMPLATE (friend_type))
5375 new_friend_type = friend_type;
5378 tree ns = decl_namespace_context (TYPE_MAIN_DECL (friend_type));
5380 /* The call to xref_tag_from_type does injection for friend
5382 push_nested_namespace (ns);
5384 xref_tag_from_type (friend_type, NULL_TREE, 1);
5385 pop_nested_namespace (ns);
5388 if (TREE_CODE (friend_type) == TEMPLATE_DECL)
5389 /* Trick make_friend_class into realizing that the friend
5390 we're adding is a template, not an ordinary class. It's
5391 important that we use make_friend_class since it will
5392 perform some error-checking and output cross-reference
5394 ++processing_template_decl;
5396 if (new_friend_type != error_mark_node)
5397 make_friend_class (type, new_friend_type,
5398 /*complain=*/false);
5400 if (TREE_CODE (friend_type) == TEMPLATE_DECL)
5401 --processing_template_decl;
5404 /* Build new DECL_FRIENDLIST. */
5405 add_friend (type, tsubst_friend_function (t, args),
5406 /*complain=*/false);
5410 /* Set the file and line number information to whatever is given for
5411 the class itself. This puts error messages involving generated
5412 implicit functions at a predictable point, and the same point
5413 that would be used for non-template classes. */
5414 typedecl = TYPE_MAIN_DECL (type);
5415 input_location = DECL_SOURCE_LOCATION (typedecl);
5417 unreverse_member_declarations (type);
5418 finish_struct_1 (type);
5420 /* Clear this now so repo_template_used is happy. */
5421 TYPE_BEING_DEFINED (type) = 0;
5422 repo_template_used (type);
5424 /* Now that the class is complete, instantiate default arguments for
5425 any member functions. We don't do this earlier because the
5426 default arguments may reference members of the class. */
5427 if (!PRIMARY_TEMPLATE_P (template))
5428 for (t = TYPE_METHODS (type); t; t = TREE_CHAIN (t))
5429 if (TREE_CODE (t) == FUNCTION_DECL
5430 /* Implicitly generated member functions will not have template
5431 information; they are not instantiations, but instead are
5432 created "fresh" for each instantiation. */
5433 && DECL_TEMPLATE_INFO (t))
5434 tsubst_default_arguments (t);
5437 pop_from_top_level ();
5438 pop_deferring_access_checks ();
5441 if (TYPE_CONTAINS_VPTR_P (type))
5442 keyed_classes = tree_cons (NULL_TREE, type, keyed_classes);
5448 tsubst_template_arg (tree t, tree args, tsubst_flags_t complain, tree in_decl)
5454 else if (TYPE_P (t))
5455 r = tsubst (t, args, complain, in_decl);
5458 r = tsubst_expr (t, args, complain, in_decl);
5460 if (!uses_template_parms (r))
5462 /* Sometimes, one of the args was an expression involving a
5463 template constant parameter, like N - 1. Now that we've
5464 tsubst'd, we might have something like 2 - 1. This will
5465 confuse lookup_template_class, so we do constant folding
5466 here. We have to unset processing_template_decl, to fool
5467 tsubst_copy_and_build() into building an actual tree. */
5469 /* If the TREE_TYPE of ARG is not NULL_TREE, ARG is already
5470 as simple as it's going to get, and trying to reprocess
5471 the trees will break. Once tsubst_expr et al DTRT for
5472 non-dependent exprs, this code can go away, as the type
5473 will always be set. */
5476 int saved_processing_template_decl = processing_template_decl;
5477 processing_template_decl = 0;
5478 r = tsubst_copy_and_build (r, /*args=*/NULL_TREE,
5479 tf_error, /*in_decl=*/NULL_TREE,
5480 /*function_p=*/false);
5481 processing_template_decl = saved_processing_template_decl;
5489 /* Substitute ARGS into the vector or list of template arguments T. */
5492 tsubst_template_args (tree t, tree args, tsubst_flags_t complain, tree in_decl)
5494 int len = TREE_VEC_LENGTH (t);
5495 int need_new = 0, i;
5496 tree *elts = alloca (len * sizeof (tree));
5498 for (i = 0; i < len; i++)
5500 tree orig_arg = TREE_VEC_ELT (t, i);
5503 if (TREE_CODE (orig_arg) == TREE_VEC)
5504 new_arg = tsubst_template_args (orig_arg, args, complain, in_decl);
5506 new_arg = tsubst_template_arg (orig_arg, args, complain, in_decl);
5508 if (new_arg == error_mark_node)
5509 return error_mark_node;
5512 if (new_arg != orig_arg)
5519 t = make_tree_vec (len);
5520 for (i = 0; i < len; i++)
5521 TREE_VEC_ELT (t, i) = elts[i];
5526 /* Return the result of substituting ARGS into the template parameters
5527 given by PARMS. If there are m levels of ARGS and m + n levels of
5528 PARMS, then the result will contain n levels of PARMS. For
5529 example, if PARMS is `template <class T> template <class U>
5530 template <T*, U, class V>' and ARGS is {{int}, {double}} then the
5531 result will be `template <int*, double, class V>'. */
5534 tsubst_template_parms (tree parms, tree args, tsubst_flags_t complain)
5539 for (new_parms = &r;
5540 TMPL_PARMS_DEPTH (parms) > TMPL_ARGS_DEPTH (args);
5541 new_parms = &(TREE_CHAIN (*new_parms)),
5542 parms = TREE_CHAIN (parms))
5545 make_tree_vec (TREE_VEC_LENGTH (TREE_VALUE (parms)));
5548 for (i = 0; i < TREE_VEC_LENGTH (new_vec); ++i)
5550 tree tuple = TREE_VEC_ELT (TREE_VALUE (parms), i);
5551 tree default_value = TREE_PURPOSE (tuple);
5552 tree parm_decl = TREE_VALUE (tuple);
5554 parm_decl = tsubst (parm_decl, args, complain, NULL_TREE);
5555 default_value = tsubst_template_arg (default_value, args,
5556 complain, NULL_TREE);
5558 tuple = build_tree_list (default_value, parm_decl);
5559 TREE_VEC_ELT (new_vec, i) = tuple;
5563 tree_cons (size_int (TMPL_PARMS_DEPTH (parms)
5564 - TMPL_ARGS_DEPTH (args)),
5565 new_vec, NULL_TREE);
5571 /* Substitute the ARGS into the indicated aggregate (or enumeration)
5572 type T. If T is not an aggregate or enumeration type, it is
5573 handled as if by tsubst. IN_DECL is as for tsubst. If
5574 ENTERING_SCOPE is nonzero, T is the context for a template which
5575 we are presently tsubst'ing. Return the substituted value. */
5578 tsubst_aggr_type (tree t,
5580 tsubst_flags_t complain,
5587 switch (TREE_CODE (t))
5590 if (TYPE_PTRMEMFUNC_P (t))
5591 return tsubst (TYPE_PTRMEMFUNC_FN_TYPE (t), args, complain, in_decl);
5593 /* else fall through */
5596 if (TYPE_TEMPLATE_INFO (t))
5602 /* First, determine the context for the type we are looking
5604 context = TYPE_CONTEXT (t);
5606 context = tsubst_aggr_type (context, args, complain,
5607 in_decl, /*entering_scope=*/1);
5609 /* Then, figure out what arguments are appropriate for the
5610 type we are trying to find. For example, given:
5612 template <class T> struct S;
5613 template <class T, class U> void f(T, U) { S<U> su; }
5615 and supposing that we are instantiating f<int, double>,
5616 then our ARGS will be {int, double}, but, when looking up
5617 S we only want {double}. */
5618 argvec = tsubst_template_args (TYPE_TI_ARGS (t), args,
5620 if (argvec == error_mark_node)
5621 return error_mark_node;
5623 r = lookup_template_class (t, argvec, in_decl, context,
5624 entering_scope, complain);
5626 return cp_build_qualified_type_real (r, TYPE_QUALS (t), complain);
5629 /* This is not a template type, so there's nothing to do. */
5633 return tsubst (t, args, complain, in_decl);
5637 /* Substitute into the default argument ARG (a default argument for
5638 FN), which has the indicated TYPE. */
5641 tsubst_default_argument (tree fn, tree type, tree arg)
5643 /* This default argument came from a template. Instantiate the
5644 default argument here, not in tsubst. In the case of
5653 we must be careful to do name lookup in the scope of S<T>,
5654 rather than in the current class.
5656 ??? current_class_type affects a lot more than name lookup. This is
5657 very fragile. Fortunately, it will go away when we do 2-phase name
5658 binding properly. */
5660 /* FN is already the desired FUNCTION_DECL. */
5661 push_access_scope (fn);
5663 arg = tsubst_expr (arg, DECL_TI_ARGS (fn),
5664 tf_error | tf_warning, NULL_TREE);
5666 pop_access_scope (fn);
5668 /* Make sure the default argument is reasonable. */
5669 arg = check_default_argument (type, arg);
5674 /* Substitute into all the default arguments for FN. */
5677 tsubst_default_arguments (tree fn)
5682 tmpl_args = DECL_TI_ARGS (fn);
5684 /* If this function is not yet instantiated, we certainly don't need
5685 its default arguments. */
5686 if (uses_template_parms (tmpl_args))
5689 for (arg = TYPE_ARG_TYPES (TREE_TYPE (fn));
5691 arg = TREE_CHAIN (arg))
5692 if (TREE_PURPOSE (arg))
5693 TREE_PURPOSE (arg) = tsubst_default_argument (fn,
5695 TREE_PURPOSE (arg));
5698 /* Substitute the ARGS into the T, which is a _DECL. TYPE is the
5699 (already computed) substitution of ARGS into TREE_TYPE (T), if
5700 appropriate. Return the result of the substitution. Issue error
5701 and warning messages under control of COMPLAIN. */
5704 tsubst_decl (tree t, tree args, tree type, tsubst_flags_t complain)
5706 location_t saved_loc;
5710 /* Set the filename and linenumber to improve error-reporting. */
5711 saved_loc = input_location;
5712 input_location = DECL_SOURCE_LOCATION (t);
5714 switch (TREE_CODE (t))
5718 /* We can get here when processing a member template function
5719 of a template class. */
5720 tree decl = DECL_TEMPLATE_RESULT (t);
5722 int is_template_template_parm = DECL_TEMPLATE_TEMPLATE_PARM_P (t);
5724 if (!is_template_template_parm)
5726 /* We might already have an instance of this template.
5727 The ARGS are for the surrounding class type, so the
5728 full args contain the tsubst'd args for the context,
5729 plus the innermost args from the template decl. */
5730 tree tmpl_args = DECL_CLASS_TEMPLATE_P (t)
5731 ? CLASSTYPE_TI_ARGS (TREE_TYPE (t))
5732 : DECL_TI_ARGS (DECL_TEMPLATE_RESULT (t));
5735 full_args = tsubst_template_args (tmpl_args, args,
5738 /* tsubst_template_args doesn't copy the vector if
5739 nothing changed. But, *something* should have
5741 my_friendly_assert (full_args != tmpl_args, 0);
5743 spec = retrieve_specialization (t, full_args);
5744 if (spec != NULL_TREE)
5751 /* Make a new template decl. It will be similar to the
5752 original, but will record the current template arguments.
5753 We also create a new function declaration, which is just
5754 like the old one, but points to this new template, rather
5755 than the old one. */
5757 my_friendly_assert (DECL_LANG_SPECIFIC (r) != 0, 0);
5758 TREE_CHAIN (r) = NULL_TREE;
5760 if (is_template_template_parm)
5762 tree new_decl = tsubst (decl, args, complain, in_decl);
5763 DECL_TEMPLATE_RESULT (r) = new_decl;
5764 TREE_TYPE (r) = TREE_TYPE (new_decl);
5769 = tsubst_aggr_type (DECL_CONTEXT (t), args,
5771 /*entering_scope=*/1);
5772 DECL_TEMPLATE_INFO (r) = build_tree_list (t, args);
5774 if (TREE_CODE (decl) == TYPE_DECL)
5776 tree new_type = tsubst (TREE_TYPE (t), args, complain, in_decl);
5777 TREE_TYPE (r) = new_type;
5778 CLASSTYPE_TI_TEMPLATE (new_type) = r;
5779 DECL_TEMPLATE_RESULT (r) = TYPE_MAIN_DECL (new_type);
5780 DECL_TI_ARGS (r) = CLASSTYPE_TI_ARGS (new_type);
5784 tree new_decl = tsubst (decl, args, complain, in_decl);
5785 if (new_decl == error_mark_node)
5786 return error_mark_node;
5788 DECL_TEMPLATE_RESULT (r) = new_decl;
5789 DECL_TI_TEMPLATE (new_decl) = r;
5790 TREE_TYPE (r) = TREE_TYPE (new_decl);
5791 DECL_TI_ARGS (r) = DECL_TI_ARGS (new_decl);
5794 SET_DECL_IMPLICIT_INSTANTIATION (r);
5795 DECL_TEMPLATE_INSTANTIATIONS (r) = NULL_TREE;
5796 DECL_TEMPLATE_SPECIALIZATIONS (r) = NULL_TREE;
5798 /* The template parameters for this new template are all the
5799 template parameters for the old template, except the
5800 outermost level of parameters. */
5801 DECL_TEMPLATE_PARMS (r)
5802 = tsubst_template_parms (DECL_TEMPLATE_PARMS (t), args,
5805 if (PRIMARY_TEMPLATE_P (t))
5806 DECL_PRIMARY_TEMPLATE (r) = r;
5808 if (TREE_CODE (decl) != TYPE_DECL)
5809 /* Record this non-type partial instantiation. */
5810 register_specialization (r, t,
5811 DECL_TI_ARGS (DECL_TEMPLATE_RESULT (r)));
5818 tree argvec = NULL_TREE;
5825 /* Nobody should be tsubst'ing into non-template functions. */
5826 my_friendly_assert (DECL_TEMPLATE_INFO (t) != NULL_TREE, 0);
5828 if (TREE_CODE (DECL_TI_TEMPLATE (t)) == TEMPLATE_DECL)
5833 /* If T is not dependent, just return it. We have to
5834 increment PROCESSING_TEMPLATE_DECL because
5835 value_dependent_expression_p assumes that nothing is
5836 dependent when PROCESSING_TEMPLATE_DECL is zero. */
5837 ++processing_template_decl;
5838 dependent_p = value_dependent_expression_p (t);
5839 --processing_template_decl;
5843 /* Calculate the most general template of which R is a
5844 specialization, and the complete set of arguments used to
5846 gen_tmpl = most_general_template (DECL_TI_TEMPLATE (t));
5847 argvec = tsubst_template_args (DECL_TI_ARGS
5848 (DECL_TEMPLATE_RESULT (gen_tmpl)),
5849 args, complain, in_decl);
5851 /* Check to see if we already have this specialization. */
5852 spec = retrieve_specialization (gen_tmpl, argvec);
5860 /* We can see more levels of arguments than parameters if
5861 there was a specialization of a member template, like
5864 template <class T> struct S { template <class U> void f(); }
5865 template <> template <class U> void S<int>::f(U);
5867 Here, we'll be substituting into the specialization,
5868 because that's where we can find the code we actually
5869 want to generate, but we'll have enough arguments for
5870 the most general template.
5872 We also deal with the peculiar case:
5874 template <class T> struct S {
5875 template <class U> friend void f();
5877 template <class U> void f() {}
5879 template void f<double>();
5881 Here, the ARGS for the instantiation of will be {int,
5882 double}. But, we only need as many ARGS as there are
5883 levels of template parameters in CODE_PATTERN. We are
5884 careful not to get fooled into reducing the ARGS in
5887 template <class T> struct S { template <class U> void f(U); }
5888 template <class T> template <> void S<T>::f(int) {}
5890 which we can spot because the pattern will be a
5891 specialization in this case. */
5892 args_depth = TMPL_ARGS_DEPTH (args);
5894 TMPL_PARMS_DEPTH (DECL_TEMPLATE_PARMS (DECL_TI_TEMPLATE (t)));
5895 if (args_depth > parms_depth
5896 && !DECL_TEMPLATE_SPECIALIZATION (t))
5897 args = get_innermost_template_args (args, parms_depth);
5901 /* This special case arises when we have something like this:
5903 template <class T> struct S {
5904 friend void f<int>(int, double);
5907 Here, the DECL_TI_TEMPLATE for the friend declaration
5908 will be an IDENTIFIER_NODE. We are being called from
5909 tsubst_friend_function, and we want only to create a
5910 new decl (R) with appropriate types so that we can call
5911 determine_specialization. */
5912 gen_tmpl = NULL_TREE;
5915 if (DECL_CLASS_SCOPE_P (t))
5917 if (DECL_NAME (t) == constructor_name (DECL_CONTEXT (t)))
5921 ctx = tsubst_aggr_type (DECL_CONTEXT (t), args,
5922 complain, t, /*entering_scope=*/1);
5927 ctx = DECL_CONTEXT (t);
5929 type = tsubst (type, args, complain, in_decl);
5930 if (type == error_mark_node)
5931 return error_mark_node;
5933 /* We do NOT check for matching decls pushed separately at this
5934 point, as they may not represent instantiations of this
5935 template, and in any case are considered separate under the
5938 DECL_USE_TEMPLATE (r) = 0;
5939 TREE_TYPE (r) = type;
5940 /* Clear out the mangled name and RTL for the instantiation. */
5941 SET_DECL_ASSEMBLER_NAME (r, NULL_TREE);
5942 SET_DECL_RTL (r, NULL_RTX);
5944 DECL_CONTEXT (r) = ctx;
5946 if (member && DECL_CONV_FN_P (r))
5947 /* Type-conversion operator. Reconstruct the name, in
5948 case it's the name of one of the template's parameters. */
5949 DECL_NAME (r) = mangle_conv_op_name_for_type (TREE_TYPE (type));
5951 DECL_ARGUMENTS (r) = tsubst (DECL_ARGUMENTS (t), args,
5953 DECL_RESULT (r) = NULL_TREE;
5955 TREE_STATIC (r) = 0;
5956 TREE_PUBLIC (r) = TREE_PUBLIC (t);
5957 DECL_EXTERNAL (r) = 1;
5958 DECL_INTERFACE_KNOWN (r) = 0;
5959 DECL_DEFER_OUTPUT (r) = 0;
5960 TREE_CHAIN (r) = NULL_TREE;
5961 DECL_PENDING_INLINE_INFO (r) = 0;
5962 DECL_PENDING_INLINE_P (r) = 0;
5963 DECL_SAVED_TREE (r) = NULL_TREE;
5965 if (DECL_CLONED_FUNCTION (r))
5967 DECL_CLONED_FUNCTION (r) = tsubst (DECL_CLONED_FUNCTION (t),
5969 TREE_CHAIN (r) = TREE_CHAIN (DECL_CLONED_FUNCTION (r));
5970 TREE_CHAIN (DECL_CLONED_FUNCTION (r)) = r;
5973 /* Set up the DECL_TEMPLATE_INFO for R. There's no need to do
5974 this in the special friend case mentioned above where
5975 GEN_TMPL is NULL. */
5978 DECL_TEMPLATE_INFO (r)
5979 = tree_cons (gen_tmpl, argvec, NULL_TREE);
5980 SET_DECL_IMPLICIT_INSTANTIATION (r);
5981 register_specialization (r, gen_tmpl, argvec);
5983 /* We're not supposed to instantiate default arguments
5984 until they are called, for a template. But, for a
5987 template <class T> void f ()
5988 { extern void g(int i = T()); }
5990 we should do the substitution when the template is
5991 instantiated. We handle the member function case in
5992 instantiate_class_template since the default arguments
5993 might refer to other members of the class. */
5995 && !PRIMARY_TEMPLATE_P (gen_tmpl)
5996 && !uses_template_parms (argvec))
5997 tsubst_default_arguments (r);
6000 /* Copy the list of befriending classes. */
6001 for (friends = &DECL_BEFRIENDING_CLASSES (r);
6003 friends = &TREE_CHAIN (*friends))
6005 *friends = copy_node (*friends);
6006 TREE_VALUE (*friends) = tsubst (TREE_VALUE (*friends),
6011 if (DECL_CONSTRUCTOR_P (r) || DECL_DESTRUCTOR_P (r))
6013 maybe_retrofit_in_chrg (r);
6014 if (DECL_CONSTRUCTOR_P (r))
6015 grok_ctor_properties (ctx, r);
6016 /* If this is an instantiation of a member template, clone it.
6017 If it isn't, that'll be handled by
6018 clone_constructors_and_destructors. */
6019 if (PRIMARY_TEMPLATE_P (gen_tmpl))
6020 clone_function_decl (r, /*update_method_vec_p=*/0);
6022 else if (IDENTIFIER_OPNAME_P (DECL_NAME (r)))
6023 grok_op_properties (r, DECL_FRIEND_P (r),
6024 (complain & tf_error) != 0);
6031 if (DECL_TEMPLATE_PARM_P (t))
6032 SET_DECL_TEMPLATE_PARM_P (r);
6034 TREE_TYPE (r) = type;
6035 c_apply_type_quals_to_decl (cp_type_quals (type), r);
6037 if (DECL_INITIAL (r))
6039 if (TREE_CODE (DECL_INITIAL (r)) != TEMPLATE_PARM_INDEX)
6040 DECL_INITIAL (r) = TREE_TYPE (r);
6042 DECL_INITIAL (r) = tsubst (DECL_INITIAL (r), args,
6046 DECL_CONTEXT (r) = NULL_TREE;
6048 if (!DECL_TEMPLATE_PARM_P (r))
6049 DECL_ARG_TYPE (r) = type_passed_as (type);
6051 TREE_CHAIN (r) = tsubst (TREE_CHAIN (t), args,
6052 complain, TREE_CHAIN (t));
6059 TREE_TYPE (r) = type;
6060 c_apply_type_quals_to_decl (cp_type_quals (type), r);
6062 /* We don't have to set DECL_CONTEXT here; it is set by
6063 finish_member_declaration. */
6064 DECL_INITIAL (r) = tsubst_expr (DECL_INITIAL (t), args,
6066 TREE_CHAIN (r) = NULL_TREE;
6067 if (VOID_TYPE_P (type))
6068 cp_error_at ("instantiation of `%D' as type `%T'", r, type);
6075 /* It is not a dependent using decl any more. */
6076 TREE_TYPE (r) = void_type_node;
6078 = tsubst_copy (DECL_INITIAL (t), args, complain, in_decl);
6079 TREE_CHAIN (r) = NULL_TREE;
6084 if (TREE_CODE (type) == TEMPLATE_TEMPLATE_PARM
6085 || t == TYPE_MAIN_DECL (TREE_TYPE (t)))
6087 /* If this is the canonical decl, we don't have to mess with
6088 instantiations, and often we can't (for typename, template
6089 type parms and such). Note that TYPE_NAME is not correct for
6090 the above test if we've copied the type for a typedef. */
6091 r = TYPE_NAME (type);
6099 tree argvec = NULL_TREE;
6100 tree gen_tmpl = NULL_TREE;
6102 tree tmpl = NULL_TREE;
6106 /* Assume this is a non-local variable. */
6109 if (TYPE_P (CP_DECL_CONTEXT (t)))
6110 ctx = tsubst_aggr_type (DECL_CONTEXT (t), args,
6112 in_decl, /*entering_scope=*/1);
6113 else if (DECL_NAMESPACE_SCOPE_P (t))
6114 ctx = DECL_CONTEXT (t);
6117 /* Subsequent calls to pushdecl will fill this in. */
6122 /* Check to see if we already have this specialization. */
6125 tmpl = DECL_TI_TEMPLATE (t);
6126 gen_tmpl = most_general_template (tmpl);
6127 argvec = tsubst (DECL_TI_ARGS (t), args, complain, in_decl);
6128 spec = retrieve_specialization (gen_tmpl, argvec);
6131 spec = retrieve_local_specialization (t);
6140 if (TREE_CODE (r) == VAR_DECL)
6142 type = complete_type (type);
6143 DECL_INITIALIZED_BY_CONSTANT_EXPRESSION_P (r)
6144 = DECL_INITIALIZED_BY_CONSTANT_EXPRESSION_P (t);
6146 else if (DECL_SELF_REFERENCE_P (t))
6147 SET_DECL_SELF_REFERENCE_P (r);
6148 TREE_TYPE (r) = type;
6149 c_apply_type_quals_to_decl (cp_type_quals (type), r);
6150 DECL_CONTEXT (r) = ctx;
6151 /* Clear out the mangled name and RTL for the instantiation. */
6152 SET_DECL_ASSEMBLER_NAME (r, NULL_TREE);
6153 SET_DECL_RTL (r, NULL_RTX);
6155 /* Don't try to expand the initializer until someone tries to use
6156 this variable; otherwise we run into circular dependencies. */
6157 DECL_INITIAL (r) = NULL_TREE;
6158 SET_DECL_RTL (r, NULL_RTX);
6159 DECL_SIZE (r) = DECL_SIZE_UNIT (r) = 0;
6161 /* Even if the original location is out of scope, the newly
6162 substituted one is not. */
6163 if (TREE_CODE (r) == VAR_DECL)
6165 DECL_DEAD_FOR_LOCAL (r) = 0;
6166 DECL_INITIALIZED_P (r) = 0;
6171 /* A static data member declaration is always marked
6172 external when it is declared in-class, even if an
6173 initializer is present. We mimic the non-template
6175 DECL_EXTERNAL (r) = 1;
6177 register_specialization (r, gen_tmpl, argvec);
6178 DECL_TEMPLATE_INFO (r) = tree_cons (tmpl, argvec, NULL_TREE);
6179 SET_DECL_IMPLICIT_INSTANTIATION (r);
6182 register_local_specialization (r, t);
6184 TREE_CHAIN (r) = NULL_TREE;
6185 if (TREE_CODE (r) == VAR_DECL && VOID_TYPE_P (type))
6186 cp_error_at ("instantiation of `%D' as type `%T'", r, type);
6187 /* Compute the size, alignment, etc. of R. */
6196 /* Restore the file and line information. */
6197 input_location = saved_loc;
6202 /* Substitute into the ARG_TYPES of a function type. */
6205 tsubst_arg_types (tree arg_types,
6207 tsubst_flags_t complain,
6210 tree remaining_arg_types;
6213 if (!arg_types || arg_types == void_list_node)
6216 remaining_arg_types = tsubst_arg_types (TREE_CHAIN (arg_types),
6217 args, complain, in_decl);
6218 if (remaining_arg_types == error_mark_node)
6219 return error_mark_node;
6221 type = tsubst (TREE_VALUE (arg_types), args, complain, in_decl);
6222 if (type == error_mark_node)
6223 return error_mark_node;
6224 if (VOID_TYPE_P (type))
6226 if (complain & tf_error)
6228 error ("invalid parameter type `%T'", type);
6230 cp_error_at ("in declaration `%D'", in_decl);
6232 return error_mark_node;
6235 /* Do array-to-pointer, function-to-pointer conversion, and ignore
6236 top-level qualifiers as required. */
6237 type = TYPE_MAIN_VARIANT (type_decays_to (type));
6239 /* Note that we do not substitute into default arguments here. The
6240 standard mandates that they be instantiated only when needed,
6241 which is done in build_over_call. */
6242 return hash_tree_cons (TREE_PURPOSE (arg_types), type,
6243 remaining_arg_types);
6247 /* Substitute into a FUNCTION_TYPE or METHOD_TYPE. This routine does
6248 *not* handle the exception-specification for FNTYPE, because the
6249 initial substitution of explicitly provided template parameters
6250 during argument deduction forbids substitution into the
6251 exception-specification:
6255 All references in the function type of the function template to the
6256 corresponding template parameters are replaced by the specified tem-
6257 plate argument values. If a substitution in a template parameter or
6258 in the function type of the function template results in an invalid
6259 type, type deduction fails. [Note: The equivalent substitution in
6260 exception specifications is done only when the function is instanti-
6261 ated, at which point a program is ill-formed if the substitution
6262 results in an invalid type.] */
6265 tsubst_function_type (tree t,
6267 tsubst_flags_t complain,
6274 /* The TYPE_CONTEXT is not used for function/method types. */
6275 my_friendly_assert (TYPE_CONTEXT (t) == NULL_TREE, 0);
6277 /* Substitute the return type. */
6278 return_type = tsubst (TREE_TYPE (t), args, complain, in_decl);
6279 if (return_type == error_mark_node)
6280 return error_mark_node;
6282 /* Substitute the argument types. */
6283 arg_types = tsubst_arg_types (TYPE_ARG_TYPES (t), args,
6285 if (arg_types == error_mark_node)
6286 return error_mark_node;
6288 /* Construct a new type node and return it. */
6289 if (TREE_CODE (t) == FUNCTION_TYPE)
6290 fntype = build_function_type (return_type, arg_types);
6293 tree r = TREE_TYPE (TREE_VALUE (arg_types));
6294 if (! IS_AGGR_TYPE (r))
6298 Type deduction may fail for any of the following
6301 -- Attempting to create "pointer to member of T" when T
6302 is not a class type. */
6303 if (complain & tf_error)
6304 error ("creating pointer to member function of non-class type `%T'",
6306 return error_mark_node;
6309 fntype = build_method_type_directly (r, return_type,
6310 TREE_CHAIN (arg_types));
6312 fntype = cp_build_qualified_type_real (fntype, TYPE_QUALS (t), complain);
6313 fntype = build_type_attribute_variant (fntype, TYPE_ATTRIBUTES (t));
6318 /* Substitute into the PARMS of a call-declarator. */
6321 tsubst_call_declarator_parms (tree parms,
6323 tsubst_flags_t complain,
6330 if (!parms || parms == void_list_node)
6333 new_parms = tsubst_call_declarator_parms (TREE_CHAIN (parms),
6334 args, complain, in_decl);
6336 /* Figure out the type of this parameter. */
6337 type = tsubst (TREE_VALUE (parms), args, complain, in_decl);
6339 /* Figure out the default argument as well. Note that we use
6340 tsubst_expr since the default argument is really an expression. */
6341 defarg = tsubst_expr (TREE_PURPOSE (parms), args, complain, in_decl);
6343 /* Chain this parameter on to the front of those we have already
6344 processed. We don't use hash_tree_cons because that function
6345 doesn't check TREE_PARMLIST. */
6346 new_parms = tree_cons (defarg, type, new_parms);
6348 /* And note that these are parameters. */
6349 TREE_PARMLIST (new_parms) = 1;
6354 /* Take the tree structure T and replace template parameters used
6355 therein with the argument vector ARGS. IN_DECL is an associated
6356 decl for diagnostics. If an error occurs, returns ERROR_MARK_NODE.
6357 Issue error and warning messages under control of COMPLAIN. Note
6358 that we must be relatively non-tolerant of extensions here, in
6359 order to preserve conformance; if we allow substitutions that
6360 should not be allowed, we may allow argument deductions that should
6361 not succeed, and therefore report ambiguous overload situations
6362 where there are none. In theory, we could allow the substitution,
6363 but indicate that it should have failed, and allow our caller to
6364 make sure that the right thing happens, but we don't try to do this
6367 This function is used for dealing with types, decls and the like;
6368 for expressions, use tsubst_expr or tsubst_copy. */
6371 tsubst (tree t, tree args, tsubst_flags_t complain, tree in_decl)
6375 if (t == NULL_TREE || t == error_mark_node
6376 || t == integer_type_node
6377 || t == void_type_node
6378 || t == char_type_node
6379 || TREE_CODE (t) == NAMESPACE_DECL)
6382 if (TREE_CODE (t) == IDENTIFIER_NODE)
6383 type = IDENTIFIER_TYPE_VALUE (t);
6385 type = TREE_TYPE (t);
6387 my_friendly_assert (type != unknown_type_node, 20030716);
6389 if (type && TREE_CODE (t) != FUNCTION_DECL
6390 && TREE_CODE (t) != TYPENAME_TYPE
6391 && TREE_CODE (t) != TEMPLATE_DECL
6392 && TREE_CODE (t) != IDENTIFIER_NODE
6393 && TREE_CODE (t) != FUNCTION_TYPE
6394 && TREE_CODE (t) != METHOD_TYPE)
6395 type = tsubst (type, args, complain, in_decl);
6396 if (type == error_mark_node)
6397 return error_mark_node;
6400 return tsubst_decl (t, args, type, complain);
6402 switch (TREE_CODE (t))
6407 return tsubst_aggr_type (t, args, complain, in_decl,
6408 /*entering_scope=*/0);
6411 case IDENTIFIER_NODE:
6423 if (t == integer_type_node)
6426 if (TREE_CODE (TYPE_MIN_VALUE (t)) == INTEGER_CST
6427 && TREE_CODE (TYPE_MAX_VALUE (t)) == INTEGER_CST)
6431 tree max, omax = TREE_OPERAND (TYPE_MAX_VALUE (t), 0);
6433 /* The array dimension behaves like a non-type template arg,
6434 in that we want to fold it as much as possible. */
6435 max = tsubst_template_arg (omax, args, complain, in_decl);
6436 if (!processing_template_decl)
6437 max = decl_constant_value (max);
6439 if (processing_template_decl
6440 /* When providing explicit arguments to a template
6441 function, but leaving some arguments for subsequent
6442 deduction, MAX may be template-dependent even if we're
6443 not PROCESSING_TEMPLATE_DECL. We still need to check for
6444 template parms, though; MAX won't be an INTEGER_CST for
6445 dynamic arrays, either. */
6446 || (TREE_CODE (max) != INTEGER_CST
6447 && uses_template_parms (max)))
6449 tree itype = make_node (INTEGER_TYPE);
6450 TYPE_MIN_VALUE (itype) = size_zero_node;
6451 TYPE_MAX_VALUE (itype) = build_min (MINUS_EXPR, sizetype, max,
6456 if (integer_zerop (omax))
6458 /* Still allow an explicit array of size zero. */
6460 pedwarn ("creating array with size zero");
6462 else if (integer_zerop (max)
6463 || (TREE_CODE (max) == INTEGER_CST
6464 && INT_CST_LT (max, integer_zero_node)))
6468 Type deduction may fail for any of the following
6471 Attempting to create an array with a size that is
6472 zero or negative. */
6473 if (complain & tf_error)
6474 error ("creating array with size zero (`%E')", max);
6476 return error_mark_node;
6479 return compute_array_index_type (NULL_TREE, max);
6482 case TEMPLATE_TYPE_PARM:
6483 case TEMPLATE_TEMPLATE_PARM:
6484 case BOUND_TEMPLATE_TEMPLATE_PARM:
6485 case TEMPLATE_PARM_INDEX:
6493 if (TREE_CODE (t) == TEMPLATE_TYPE_PARM
6494 || TREE_CODE (t) == TEMPLATE_TEMPLATE_PARM
6495 || TREE_CODE (t) == BOUND_TEMPLATE_TEMPLATE_PARM)
6497 idx = TEMPLATE_TYPE_IDX (t);
6498 level = TEMPLATE_TYPE_LEVEL (t);
6502 idx = TEMPLATE_PARM_IDX (t);
6503 level = TEMPLATE_PARM_LEVEL (t);
6506 if (TREE_VEC_LENGTH (args) > 0)
6508 tree arg = NULL_TREE;
6510 levels = TMPL_ARGS_DEPTH (args);
6511 if (level <= levels)
6512 arg = TMPL_ARG (args, level, idx);
6514 if (arg == error_mark_node)
6515 return error_mark_node;
6516 else if (arg != NULL_TREE)
6518 if (TREE_CODE (t) == TEMPLATE_TYPE_PARM)
6520 my_friendly_assert (TYPE_P (arg), 0);
6521 return cp_build_qualified_type_real
6522 (arg, cp_type_quals (arg) | cp_type_quals (t),
6523 complain | tf_ignore_bad_quals);
6525 else if (TREE_CODE (t) == BOUND_TEMPLATE_TEMPLATE_PARM)
6527 /* We are processing a type constructed from
6528 a template template parameter */
6529 tree argvec = tsubst (TYPE_TI_ARGS (t),
6530 args, complain, in_decl);
6531 if (argvec == error_mark_node)
6532 return error_mark_node;
6534 /* We can get a TEMPLATE_TEMPLATE_PARM here when
6535 we are resolving nested-types in the signature of
6536 a member function templates.
6537 Otherwise ARG is a TEMPLATE_DECL and is the real
6538 template to be instantiated. */
6539 if (TREE_CODE (arg) == TEMPLATE_TEMPLATE_PARM)
6540 arg = TYPE_NAME (arg);
6542 r = lookup_template_class (arg,
6545 /*entering_scope=*/0,
6547 return cp_build_qualified_type_real
6548 (r, TYPE_QUALS (t), complain);
6551 /* TEMPLATE_TEMPLATE_PARM or TEMPLATE_PARM_INDEX. */
6559 /* This can happen during the attempted tsubst'ing in
6560 unify. This means that we don't yet have any information
6561 about the template parameter in question. */
6564 /* If we get here, we must have been looking at a parm for a
6565 more deeply nested template. Make a new version of this
6566 template parameter, but with a lower level. */
6567 switch (TREE_CODE (t))
6569 case TEMPLATE_TYPE_PARM:
6570 case TEMPLATE_TEMPLATE_PARM:
6571 case BOUND_TEMPLATE_TEMPLATE_PARM:
6572 if (cp_type_quals (t))
6574 r = tsubst (TYPE_MAIN_VARIANT (t), args, complain, in_decl);
6575 r = cp_build_qualified_type_real
6576 (r, cp_type_quals (t),
6577 complain | (TREE_CODE (t) == TEMPLATE_TYPE_PARM
6578 ? tf_ignore_bad_quals : 0));
6583 TEMPLATE_TYPE_PARM_INDEX (r)
6584 = reduce_template_parm_level (TEMPLATE_TYPE_PARM_INDEX (t),
6586 TYPE_STUB_DECL (r) = TYPE_NAME (r) = TEMPLATE_TYPE_DECL (r);
6587 TYPE_MAIN_VARIANT (r) = r;
6588 TYPE_POINTER_TO (r) = NULL_TREE;
6589 TYPE_REFERENCE_TO (r) = NULL_TREE;
6591 if (TREE_CODE (t) == BOUND_TEMPLATE_TEMPLATE_PARM)
6593 tree argvec = tsubst (TYPE_TI_ARGS (t), args,
6595 if (argvec == error_mark_node)
6596 return error_mark_node;
6598 TEMPLATE_TEMPLATE_PARM_TEMPLATE_INFO (r)
6599 = tree_cons (TYPE_TI_TEMPLATE (t), argvec, NULL_TREE);
6604 case TEMPLATE_PARM_INDEX:
6605 r = reduce_template_parm_level (t, type, levels);
6617 tree purpose, value, chain, result;
6619 if (t == void_list_node)
6622 purpose = TREE_PURPOSE (t);
6625 purpose = tsubst (purpose, args, complain, in_decl);
6626 if (purpose == error_mark_node)
6627 return error_mark_node;
6629 value = TREE_VALUE (t);
6632 value = tsubst (value, args, complain, in_decl);
6633 if (value == error_mark_node)
6634 return error_mark_node;
6636 chain = TREE_CHAIN (t);
6637 if (chain && chain != void_type_node)
6639 chain = tsubst (chain, args, complain, in_decl);
6640 if (chain == error_mark_node)
6641 return error_mark_node;
6643 if (purpose == TREE_PURPOSE (t)
6644 && value == TREE_VALUE (t)
6645 && chain == TREE_CHAIN (t))
6647 if (TREE_PARMLIST (t))
6649 result = tree_cons (purpose, value, chain);
6650 TREE_PARMLIST (result) = 1;
6653 result = hash_tree_cons (purpose, value, chain);
6657 if (type != NULL_TREE)
6659 /* A binfo node. We always need to make a copy, of the node
6660 itself and of its BINFO_BASETYPES. */
6664 /* Make sure type isn't a typedef copy. */
6665 type = BINFO_TYPE (TYPE_BINFO (type));
6667 TREE_TYPE (t) = complete_type (type);
6668 if (IS_AGGR_TYPE (type))
6670 BINFO_VTABLE (t) = TYPE_BINFO_VTABLE (type);
6671 BINFO_VIRTUALS (t) = TYPE_BINFO_VIRTUALS (type);
6672 if (TYPE_BINFO_BASETYPES (type) != NULL_TREE)
6673 BINFO_BASETYPES (t) = copy_node (TYPE_BINFO_BASETYPES (type));
6678 /* Otherwise, a vector of template arguments. */
6679 return tsubst_template_args (t, args, complain, in_decl);
6682 case REFERENCE_TYPE:
6684 enum tree_code code;
6686 if (type == TREE_TYPE (t) && TREE_CODE (type) != METHOD_TYPE)
6689 code = TREE_CODE (t);
6694 Type deduction may fail for any of the following
6697 -- Attempting to create a pointer to reference type.
6698 -- Attempting to create a reference to a reference type or
6699 a reference to void. */
6700 if (TREE_CODE (type) == REFERENCE_TYPE
6701 || (code == REFERENCE_TYPE && TREE_CODE (type) == VOID_TYPE))
6703 static location_t last_loc;
6705 /* We keep track of the last time we issued this error
6706 message to avoid spewing a ton of messages during a
6707 single bad template instantiation. */
6708 if (complain & tf_error
6709 && (last_loc.line != input_line
6710 || last_loc.file != input_filename))
6712 if (TREE_CODE (type) == VOID_TYPE)
6713 error ("forming reference to void");
6715 error ("forming %s to reference type `%T'",
6716 (code == POINTER_TYPE) ? "pointer" : "reference",
6718 last_loc = input_location;
6721 return error_mark_node;
6723 else if (code == POINTER_TYPE)
6725 r = build_pointer_type (type);
6726 if (TREE_CODE (type) == METHOD_TYPE)
6727 r = build_ptrmemfunc_type (r);
6730 r = build_reference_type (type);
6731 r = cp_build_qualified_type_real (r, TYPE_QUALS (t), complain);
6733 if (r != error_mark_node)
6734 /* Will this ever be needed for TYPE_..._TO values? */
6741 r = tsubst (TYPE_OFFSET_BASETYPE (t), args, complain, in_decl);
6742 if (r == error_mark_node || !IS_AGGR_TYPE (r))
6746 Type deduction may fail for any of the following
6749 -- Attempting to create "pointer to member of T" when T
6750 is not a class type. */
6751 if (complain & tf_error)
6752 error ("creating pointer to member of non-class type `%T'", r);
6753 return error_mark_node;
6755 if (TREE_CODE (type) == REFERENCE_TYPE)
6757 if (complain & tf_error)
6758 error ("creating pointer to member reference type `%T'", type);
6760 return error_mark_node;
6762 my_friendly_assert (TREE_CODE (type) != METHOD_TYPE, 20011231);
6763 if (TREE_CODE (type) == FUNCTION_TYPE)
6765 /* This is really a method type. The cv qualifiers of the
6766 this pointer should _not_ be determined by the cv
6767 qualifiers of the class type. They should be held
6768 somewhere in the FUNCTION_TYPE, but we don't do that at
6769 the moment. Consider
6770 typedef void (Func) () const;
6772 template <typename T1> void Foo (Func T1::*);
6777 method_type = build_method_type_directly (TYPE_MAIN_VARIANT (r),
6779 TYPE_ARG_TYPES (type));
6780 return build_ptrmemfunc_type (build_pointer_type (method_type));
6783 return cp_build_qualified_type_real (build_ptrmem_type (r, type),
6793 fntype = tsubst_function_type (t, args, complain, in_decl);
6794 if (fntype == error_mark_node)
6795 return error_mark_node;
6797 /* Substitute the exception specification. */
6798 raises = TYPE_RAISES_EXCEPTIONS (t);
6801 tree list = NULL_TREE;
6803 if (! TREE_VALUE (raises))
6806 for (; raises != NULL_TREE; raises = TREE_CHAIN (raises))
6808 tree spec = TREE_VALUE (raises);
6810 spec = tsubst (spec, args, complain, in_decl);
6811 if (spec == error_mark_node)
6813 list = add_exception_specifier (list, spec, complain);
6815 fntype = build_exception_variant (fntype, list);
6821 tree domain = tsubst (TYPE_DOMAIN (t), args, complain, in_decl);
6822 if (domain == error_mark_node)
6823 return error_mark_node;
6825 /* As an optimization, we avoid regenerating the array type if
6826 it will obviously be the same as T. */
6827 if (type == TREE_TYPE (t) && domain == TYPE_DOMAIN (t))
6830 /* These checks should match the ones in grokdeclarator.
6834 The deduction may fail for any of the following reasons:
6836 -- Attempting to create an array with an element type that
6837 is void, a function type, or a reference type. */
6838 if (TREE_CODE (type) == VOID_TYPE
6839 || TREE_CODE (type) == FUNCTION_TYPE
6840 || TREE_CODE (type) == REFERENCE_TYPE)
6842 if (complain & tf_error)
6843 error ("creating array of `%T'", type);
6844 return error_mark_node;
6847 r = build_cplus_array_type (type, domain);
6854 tree e1 = tsubst (TREE_OPERAND (t, 0), args, complain, in_decl);
6855 tree e2 = tsubst (TREE_OPERAND (t, 1), args, complain, in_decl);
6857 if (e1 == error_mark_node || e2 == error_mark_node)
6858 return error_mark_node;
6860 return fold (build (TREE_CODE (t), TREE_TYPE (t), e1, e2));
6866 tree e = tsubst (TREE_OPERAND (t, 0), args, complain, in_decl);
6867 if (e == error_mark_node)
6868 return error_mark_node;
6870 return fold (build (TREE_CODE (t), TREE_TYPE (t), e));
6875 tree ctx = tsubst_aggr_type (TYPE_CONTEXT (t), args, complain,
6876 in_decl, /*entering_scope=*/1);
6877 tree f = tsubst_copy (TYPENAME_TYPE_FULLNAME (t), args,
6880 if (ctx == error_mark_node || f == error_mark_node)
6881 return error_mark_node;
6883 if (!IS_AGGR_TYPE (ctx))
6885 if (complain & tf_error)
6886 error ("`%T' is not a class, struct, or union type",
6888 return error_mark_node;
6890 else if (!uses_template_parms (ctx) && !TYPE_BEING_DEFINED (ctx))
6892 /* Normally, make_typename_type does not require that the CTX
6893 have complete type in order to allow things like:
6895 template <class T> struct S { typename S<T>::X Y; };
6897 But, such constructs have already been resolved by this
6898 point, so here CTX really should have complete type, unless
6899 it's a partial instantiation. */
6900 ctx = complete_type (ctx);
6901 if (!COMPLETE_TYPE_P (ctx))
6903 if (complain & tf_error)
6904 cxx_incomplete_type_error (NULL_TREE, ctx);
6905 return error_mark_node;
6909 f = make_typename_type (ctx, f,
6910 (complain & tf_error) | tf_keep_type_decl);
6911 if (f == error_mark_node)
6913 if (TREE_CODE (f) == TYPE_DECL)
6915 complain |= tf_ignore_bad_quals;
6919 return cp_build_qualified_type_real
6920 (f, cp_type_quals (f) | cp_type_quals (t), complain);
6923 case UNBOUND_CLASS_TEMPLATE:
6925 tree ctx = tsubst_aggr_type (TYPE_CONTEXT (t), args, complain,
6926 in_decl, /*entering_scope=*/1);
6927 tree name = TYPE_IDENTIFIER (t);
6929 if (ctx == error_mark_node || name == error_mark_node)
6930 return error_mark_node;
6932 return make_unbound_class_template (ctx, name, complain);
6937 tree e = tsubst (TREE_OPERAND (t, 0), args, complain, in_decl);
6938 if (e == error_mark_node)
6939 return error_mark_node;
6940 return make_pointer_declarator (type, e);
6945 tree e = tsubst (TREE_OPERAND (t, 0), args, complain, in_decl);
6946 if (e == error_mark_node)
6947 return error_mark_node;
6948 return make_reference_declarator (type, e);
6953 tree e1 = tsubst (TREE_OPERAND (t, 0), args, complain, in_decl);
6954 tree e2 = tsubst_expr (TREE_OPERAND (t, 1), args, complain, in_decl);
6955 if (e1 == error_mark_node || e2 == error_mark_node)
6956 return error_mark_node;
6958 return build_nt (ARRAY_REF, e1, e2, tsubst_expr);
6963 tree e1 = tsubst (TREE_OPERAND (t, 0), args, complain, in_decl);
6964 tree e2 = (tsubst_call_declarator_parms
6965 (CALL_DECLARATOR_PARMS (t), args, complain, in_decl));
6966 tree e3 = tsubst (CALL_DECLARATOR_EXCEPTION_SPEC (t), args,
6969 if (e1 == error_mark_node || e2 == error_mark_node
6970 || e3 == error_mark_node)
6971 return error_mark_node;
6973 return make_call_declarator (e1, e2, CALL_DECLARATOR_QUALS (t), e3);
6978 tree e1 = tsubst (TREE_OPERAND (t, 0), args, complain, in_decl);
6979 tree e2 = tsubst (TREE_OPERAND (t, 1), args, complain, in_decl);
6980 if (e1 == error_mark_node || e2 == error_mark_node)
6981 return error_mark_node;
6983 return build_nt (TREE_CODE (t), e1, e2);
6988 tree e1 = tsubst_expr (TYPE_FIELDS (t), args, complain, in_decl);
6989 if (e1 == error_mark_node)
6990 return error_mark_node;
6992 return cp_build_qualified_type_real (TREE_TYPE (e1),
6994 | cp_type_quals (TREE_TYPE (e1)),
6999 sorry ("use of `%s' in template",
7000 tree_code_name [(int) TREE_CODE (t)]);
7001 return error_mark_node;
7005 /* Like tsubst_expr for a BASELINK. OBJECT_TYPE, if non-NULL, is the
7006 type of the expression on the left-hand side of the "." or "->"
7010 tsubst_baselink (tree baselink, tree object_type,
7011 tree args, tsubst_flags_t complain, tree in_decl)
7014 tree qualifying_scope;
7016 tree template_args = 0;
7017 bool template_id_p = false;
7019 /* A baselink indicates a function from a base class. The
7020 BASELINK_ACCESS_BINFO and BASELINK_BINFO are going to have
7021 non-dependent types; otherwise, the lookup could not have
7022 succeeded. However, they may indicate bases of the template
7023 class, rather than the instantiated class.
7025 In addition, lookups that were not ambiguous before may be
7026 ambiguous now. Therefore, we perform the lookup again. */
7027 qualifying_scope = BINFO_TYPE (BASELINK_ACCESS_BINFO (baselink));
7028 fns = BASELINK_FUNCTIONS (baselink);
7029 if (TREE_CODE (fns) == TEMPLATE_ID_EXPR)
7031 template_id_p = true;
7032 template_args = TREE_OPERAND (fns, 1);
7033 fns = TREE_OPERAND (fns, 0);
7035 template_args = tsubst_template_args (template_args, args,
7038 name = DECL_NAME (get_first_fn (fns));
7039 baselink = lookup_fnfields (qualifying_scope, name, /*protect=*/1);
7040 if (BASELINK_P (baselink) && template_id_p)
7041 BASELINK_FUNCTIONS (baselink)
7042 = build_nt (TEMPLATE_ID_EXPR,
7043 BASELINK_FUNCTIONS (baselink),
7046 object_type = current_class_type;
7047 return adjust_result_of_qualified_name_lookup (baselink,
7052 /* Like tsubst_expr for a SCOPE_REF, given by QUALIFIED_ID. DONE is
7053 true if the qualified-id will be a postfix-expression in-and-of
7054 itself; false if more of the postfix-expression follows the
7055 QUALIFIED_ID. ADDRESS_P is true if the qualified-id is the operand
7059 tsubst_qualified_id (tree qualified_id, tree args,
7060 tsubst_flags_t complain, tree in_decl,
7061 bool done, bool address_p)
7069 my_friendly_assert (TREE_CODE (qualified_id) == SCOPE_REF, 20030706);
7071 /* Figure out what name to look up. */
7072 name = TREE_OPERAND (qualified_id, 1);
7073 if (TREE_CODE (name) == TEMPLATE_ID_EXPR)
7076 template_args = TREE_OPERAND (name, 1);
7078 template_args = tsubst_template_args (template_args, args,
7080 name = TREE_OPERAND (name, 0);
7084 is_template = false;
7085 template_args = NULL_TREE;
7088 /* Substitute into the qualifying scope. When there are no ARGS, we
7089 are just trying to simplify a non-dependent expression. In that
7090 case the qualifying scope may be dependent, and, in any case,
7091 substituting will not help. */
7092 scope = TREE_OPERAND (qualified_id, 0);
7095 scope = tsubst (scope, args, complain, in_decl);
7096 expr = tsubst_copy (name, args, complain, in_decl);
7101 my_friendly_assert (!dependent_type_p (scope), 20030729);
7103 if (!BASELINK_P (name) && !DECL_P (expr))
7105 expr = lookup_qualified_name (scope, expr, /*is_type_p=*/0, false);
7106 if (TREE_CODE (TREE_CODE (expr) == TEMPLATE_DECL
7107 ? DECL_TEMPLATE_RESULT (expr) : expr) == TYPE_DECL)
7109 if (complain & tf_error)
7110 error ("`%E' names a type, but a non-type is expected",
7112 return error_mark_node;
7117 check_accessibility_of_qualified_id (expr, /*object_type=*/NULL_TREE,
7120 /* Remember that there was a reference to this entity. */
7124 if (!args && TREE_CODE (expr) == VAR_DECL)
7125 expr = DECL_INITIAL (expr);
7129 expr = lookup_template_function (expr, template_args);
7131 if (expr == error_mark_node && complain & tf_error)
7132 qualified_name_lookup_error (scope, TREE_OPERAND (qualified_id, 1));
7133 else if (TYPE_P (scope))
7135 expr = (adjust_result_of_qualified_name_lookup
7136 (expr, scope, current_class_type));
7137 expr = finish_qualified_id_expr (scope, expr, done, address_p);
7143 /* Like tsubst, but deals with expressions. This function just replaces
7144 template parms; to finish processing the resultant expression, use
7148 tsubst_copy (tree t, tree args, tsubst_flags_t complain, tree in_decl)
7150 enum tree_code code;
7153 if (t == NULL_TREE || t == error_mark_node)
7156 code = TREE_CODE (t);
7161 r = retrieve_local_specialization (t);
7162 my_friendly_assert (r != NULL, 20020903);
7170 if (DECL_TEMPLATE_PARM_P (t))
7171 return tsubst_copy (DECL_INITIAL (t), args, complain, in_decl);
7172 /* There is no need to substitute into namespace-scope
7174 if (DECL_NAMESPACE_SCOPE_P (t))
7177 /* Unfortunately, we cannot just call lookup_name here.
7180 template <int I> int f() {
7182 struct S { void g() { E e = a; } };
7185 When we instantiate f<7>::S::g(), say, lookup_name is not
7186 clever enough to find f<7>::a. */
7188 = tsubst_aggr_type (TREE_TYPE (t), args, complain, in_decl,
7189 /*entering_scope=*/0);
7191 for (v = TYPE_VALUES (enum_type);
7194 if (TREE_PURPOSE (v) == DECL_NAME (t))
7195 return TREE_VALUE (v);
7197 /* We didn't find the name. That should never happen; if
7198 name-lookup found it during preliminary parsing, we
7199 should find it again here during instantiation. */
7205 if (DECL_CONTEXT (t))
7209 ctx = tsubst_aggr_type (DECL_CONTEXT (t), args, complain, in_decl,
7210 /*entering_scope=*/1);
7211 if (ctx != DECL_CONTEXT (t))
7212 return lookup_field (ctx, DECL_NAME (t), 0, false);
7218 if ((DECL_LANG_SPECIFIC (t) && DECL_TEMPLATE_INFO (t))
7219 || local_variable_p (t))
7220 t = tsubst (t, args, complain, in_decl);
7225 return tsubst_baselink (t, current_class_type, args, complain, in_decl);
7228 if (DECL_TEMPLATE_TEMPLATE_PARM_P (t))
7229 return tsubst (TREE_TYPE (DECL_TEMPLATE_RESULT (t)),
7230 args, complain, in_decl);
7231 else if (is_member_template (t))
7232 return tsubst (t, args, complain, in_decl);
7233 else if (DECL_CLASS_SCOPE_P (t)
7234 && uses_template_parms (DECL_CONTEXT (t)))
7236 /* Template template argument like the following example need
7239 template <template <class> class TT> struct C {};
7240 template <class T> struct D {
7241 template <class U> struct E {};
7246 We are processing the template argument `E' in #1 for
7247 the template instantiation #2. Originally, `E' is a
7248 TEMPLATE_DECL with `D<T>' as its DECL_CONTEXT. Now we
7249 have to substitute this with one having context `D<int>'. */
7251 tree context = tsubst (DECL_CONTEXT (t), args, complain, in_decl);
7252 return lookup_field (context, DECL_NAME(t), 0, false);
7255 /* Ordinary template template argument. */
7259 case REINTERPRET_CAST_EXPR:
7260 case CONST_CAST_EXPR:
7261 case STATIC_CAST_EXPR:
7262 case DYNAMIC_CAST_EXPR:
7265 (code, tsubst (TREE_TYPE (t), args, complain, in_decl),
7266 tsubst_copy (TREE_OPERAND (t, 0), args, complain, in_decl));
7270 case TRUTH_NOT_EXPR:
7273 case CONVERT_EXPR: /* Unary + */
7282 (code, tsubst (TREE_TYPE (t), args, complain, in_decl),
7283 tsubst_copy (TREE_OPERAND (t, 0), args, complain, in_decl));
7290 object = tsubst_copy (TREE_OPERAND (t, 0), args, complain, in_decl);
7291 name = TREE_OPERAND (t, 1);
7292 if (TREE_CODE (name) == BIT_NOT_EXPR)
7294 name = tsubst_copy (TREE_OPERAND (name, 0), args,
7296 name = build1 (BIT_NOT_EXPR, NULL_TREE, name);
7298 else if (TREE_CODE (name) == SCOPE_REF
7299 && TREE_CODE (TREE_OPERAND (name, 1)) == BIT_NOT_EXPR)
7301 tree base = tsubst_copy (TREE_OPERAND (name, 0), args,
7303 name = TREE_OPERAND (name, 1);
7304 name = tsubst_copy (TREE_OPERAND (name, 0), args,
7306 name = build1 (BIT_NOT_EXPR, NULL_TREE, name);
7307 name = build_nt (SCOPE_REF, base, name);
7309 else if (TREE_CODE (name) == BASELINK)
7310 name = tsubst_baselink (name,
7311 non_reference (TREE_TYPE (object)),
7315 name = tsubst_copy (name, args, complain, in_decl);
7316 return build_nt (COMPONENT_REF, object, name);
7322 case TRUNC_DIV_EXPR:
7324 case FLOOR_DIV_EXPR:
7325 case ROUND_DIV_EXPR:
7326 case EXACT_DIV_EXPR:
7330 case TRUNC_MOD_EXPR:
7331 case FLOOR_MOD_EXPR:
7332 case TRUTH_ANDIF_EXPR:
7333 case TRUTH_ORIF_EXPR:
7334 case TRUTH_AND_EXPR:
7353 case PREDECREMENT_EXPR:
7354 case PREINCREMENT_EXPR:
7355 case POSTDECREMENT_EXPR:
7356 case POSTINCREMENT_EXPR:
7358 (code, tsubst_copy (TREE_OPERAND (t, 0), args, complain, in_decl),
7359 tsubst_copy (TREE_OPERAND (t, 1), args, complain, in_decl));
7362 return build_nt (code,
7363 tsubst_copy (TREE_OPERAND (t, 0), args,
7365 tsubst_copy (TREE_OPERAND (t, 1), args, complain,
7370 /* This processing should really occur in tsubst_expr. However,
7371 tsubst_expr does not recurse into expressions, since it
7372 assumes that there aren't any statements inside them. So, we
7373 need to expand the STMT_EXPR here. */
7374 if (!processing_template_decl)
7376 tree stmt_expr = begin_stmt_expr ();
7378 tsubst_expr (STMT_EXPR_STMT (t), args,
7379 complain | tf_stmt_expr_cmpd, in_decl);
7380 return finish_stmt_expr (stmt_expr, false);
7387 case PSEUDO_DTOR_EXPR:
7390 (code, tsubst_copy (TREE_OPERAND (t, 0), args, complain, in_decl),
7391 tsubst_copy (TREE_OPERAND (t, 1), args, complain, in_decl),
7392 tsubst_copy (TREE_OPERAND (t, 2), args, complain, in_decl));
7399 (code, tsubst_copy (TREE_OPERAND (t, 0), args, complain, in_decl),
7400 tsubst_copy (TREE_OPERAND (t, 1), args, complain, in_decl),
7401 tsubst_copy (TREE_OPERAND (t, 2), args, complain, in_decl));
7402 NEW_EXPR_USE_GLOBAL (r) = NEW_EXPR_USE_GLOBAL (t);
7409 (code, tsubst_copy (TREE_OPERAND (t, 0), args, complain, in_decl),
7410 tsubst_copy (TREE_OPERAND (t, 1), args, complain, in_decl));
7411 DELETE_EXPR_USE_GLOBAL (r) = DELETE_EXPR_USE_GLOBAL (t);
7412 DELETE_EXPR_USE_VEC (r) = DELETE_EXPR_USE_VEC (t);
7416 case TEMPLATE_ID_EXPR:
7418 /* Substituted template arguments */
7419 tree fn = TREE_OPERAND (t, 0);
7420 tree targs = TREE_OPERAND (t, 1);
7422 fn = tsubst_copy (fn, args, complain, in_decl);
7424 targs = tsubst_template_args (targs, args, complain, in_decl);
7426 return lookup_template_function (fn, targs);
7431 tree purpose, value, chain;
7433 if (t == void_list_node)
7436 purpose = TREE_PURPOSE (t);
7438 purpose = tsubst_copy (purpose, args, complain, in_decl);
7439 value = TREE_VALUE (t);
7441 value = tsubst_copy (value, args, complain, in_decl);
7442 chain = TREE_CHAIN (t);
7443 if (chain && chain != void_type_node)
7444 chain = tsubst_copy (chain, args, complain, in_decl);
7445 if (purpose == TREE_PURPOSE (t)
7446 && value == TREE_VALUE (t)
7447 && chain == TREE_CHAIN (t))
7449 return tree_cons (purpose, value, chain);
7456 case TEMPLATE_TYPE_PARM:
7457 case TEMPLATE_TEMPLATE_PARM:
7458 case BOUND_TEMPLATE_TEMPLATE_PARM:
7459 case TEMPLATE_PARM_INDEX:
7461 case REFERENCE_TYPE:
7467 case UNBOUND_CLASS_TEMPLATE:
7470 return tsubst (t, args, complain, in_decl);
7472 case IDENTIFIER_NODE:
7473 if (IDENTIFIER_TYPENAME_P (t))
7475 tree new_type = tsubst (TREE_TYPE (t), args, complain, in_decl);
7476 return mangle_conv_op_name_for_type (new_type);
7483 r = build_constructor
7484 (tsubst (TREE_TYPE (t), args, complain, in_decl),
7485 tsubst_copy (CONSTRUCTOR_ELTS (t), args, complain, in_decl));
7486 TREE_HAS_CONSTRUCTOR (r) = TREE_HAS_CONSTRUCTOR (t);
7491 return build_x_va_arg (tsubst_copy (TREE_OPERAND (t, 0), args, complain,
7493 tsubst (TREE_TYPE (t), args, complain, in_decl));
7500 /* Like tsubst_copy for expressions, etc. but also does semantic
7504 tsubst_expr (tree t, tree args, tsubst_flags_t complain, tree in_decl)
7507 tsubst_flags_t stmt_expr
7508 = complain & (tf_stmt_expr_cmpd | tf_stmt_expr_body);
7510 complain ^= stmt_expr;
7511 if (t == NULL_TREE || t == error_mark_node)
7514 if (processing_template_decl)
7515 return tsubst_copy (t, args, complain, in_decl);
7517 if (!STATEMENT_CODE_P (TREE_CODE (t)))
7518 return tsubst_copy_and_build (t, args, complain, in_decl,
7519 /*function_p=*/false);
7521 switch (TREE_CODE (t))
7523 case CTOR_INITIALIZER:
7525 finish_mem_initializers (tsubst_initializer_list
7526 (TREE_OPERAND (t, 0), args));
7531 finish_return_stmt (tsubst_expr (RETURN_STMT_EXPR (t),
7532 args, complain, in_decl));
7541 r = tsubst_expr (EXPR_STMT_EXPR (t), args, complain, in_decl);
7542 if (stmt_expr & tf_stmt_expr_body && !TREE_CHAIN (t))
7543 finish_stmt_expr_expr (r);
7545 finish_expr_stmt (r);
7551 do_using_directive (tsubst_expr (USING_STMT_NAMESPACE (t),
7552 args, complain, in_decl));
7561 decl = DECL_STMT_DECL (t);
7562 if (TREE_CODE (decl) == LABEL_DECL)
7563 finish_label_decl (DECL_NAME (decl));
7564 else if (TREE_CODE (decl) == USING_DECL)
7566 tree scope = DECL_INITIAL (decl);
7567 tree name = DECL_NAME (decl);
7570 scope = tsubst_expr (scope, args, complain, in_decl);
7571 decl = lookup_qualified_name (scope, name,
7572 /*is_type_p=*/false,
7573 /*complain=*/false);
7574 if (decl == error_mark_node)
7575 qualified_name_lookup_error (scope, name);
7577 do_local_using_decl (decl);
7581 init = DECL_INITIAL (decl);
7582 decl = tsubst (decl, args, complain, in_decl);
7583 if (decl != error_mark_node)
7586 DECL_INITIAL (decl) = error_mark_node;
7587 /* By marking the declaration as instantiated, we avoid
7588 trying to instantiate it. Since instantiate_decl can't
7589 handle local variables, and since we've already done
7590 all that needs to be done, that's the right thing to
7592 if (TREE_CODE (decl) == VAR_DECL)
7593 DECL_TEMPLATE_INSTANTIATED (decl) = 1;
7594 if (TREE_CODE (decl) == VAR_DECL
7595 && ANON_AGGR_TYPE_P (TREE_TYPE (decl)))
7596 /* Anonymous aggregates are a special case. */
7597 finish_anon_union (decl);
7600 maybe_push_decl (decl);
7601 if (TREE_CODE (decl) == VAR_DECL
7602 && DECL_PRETTY_FUNCTION_P (decl))
7604 /* For __PRETTY_FUNCTION__ we have to adjust the
7606 const char *const name
7607 = cxx_printable_name (current_function_decl, 2);
7608 init = cp_fname_init (name);
7609 TREE_TYPE (decl) = TREE_TYPE (init);
7612 init = tsubst_expr (init, args, complain, in_decl);
7613 cp_finish_decl (decl, init, NULL_TREE, 0);
7618 /* A DECL_STMT can also be used as an expression, in the condition
7619 clause of an if/for/while construct. If we aren't followed by
7620 another statement, return our decl. */
7621 if (TREE_CHAIN (t) == NULL_TREE)
7630 stmt = begin_for_stmt ();
7631 tsubst_expr (FOR_INIT_STMT (t), args, complain, in_decl);
7632 finish_for_init_stmt (stmt);
7633 finish_for_cond (tsubst_expr (FOR_COND (t),
7634 args, complain, in_decl),
7636 tmp = tsubst_expr (FOR_EXPR (t), args, complain, in_decl);
7637 finish_for_expr (tmp, stmt);
7638 tsubst_expr (FOR_BODY (t), args, complain, in_decl);
7639 finish_for_stmt (stmt);
7646 stmt = begin_while_stmt ();
7647 finish_while_stmt_cond (tsubst_expr (WHILE_COND (t),
7648 args, complain, in_decl),
7650 tsubst_expr (WHILE_BODY (t), args, complain, in_decl);
7651 finish_while_stmt (stmt);
7658 stmt = begin_do_stmt ();
7659 tsubst_expr (DO_BODY (t), args, complain, in_decl);
7660 finish_do_body (stmt);
7661 finish_do_stmt (tsubst_expr (DO_COND (t),
7662 args, complain, in_decl),
7670 stmt = begin_if_stmt ();
7671 finish_if_stmt_cond (tsubst_expr (IF_COND (t),
7672 args, complain, in_decl),
7675 if (tmp = THEN_CLAUSE (t), tmp)
7677 tsubst_expr (tmp, args, complain, in_decl);
7678 finish_then_clause (stmt);
7681 if (tmp = ELSE_CLAUSE (t), tmp)
7683 begin_else_clause ();
7684 tsubst_expr (tmp, args, complain, in_decl);
7685 finish_else_clause (stmt);
7695 if (COMPOUND_STMT_BODY_BLOCK (t))
7696 stmt = begin_function_body ();
7698 stmt = begin_compound_stmt (COMPOUND_STMT_NO_SCOPE (t));
7700 tsubst_expr (COMPOUND_BODY (t), args,
7701 complain | ((stmt_expr & tf_stmt_expr_cmpd) << 1),
7704 if (COMPOUND_STMT_BODY_BLOCK (t))
7705 finish_function_body (stmt);
7707 finish_compound_stmt (stmt);
7713 finish_break_stmt ();
7718 finish_continue_stmt ();
7726 stmt = begin_switch_stmt ();
7727 val = tsubst_expr (SWITCH_COND (t), args, complain, in_decl);
7728 finish_switch_cond (val, stmt);
7729 tsubst_expr (SWITCH_BODY (t), args, complain, in_decl);
7730 finish_switch_stmt (stmt);
7736 finish_case_label (tsubst_expr (CASE_LOW (t), args, complain, in_decl),
7737 tsubst_expr (CASE_HIGH (t), args, complain,
7742 input_line = STMT_LINENO (t);
7743 finish_label_stmt (DECL_NAME (LABEL_STMT_LABEL (t)));
7747 input_filename = FILE_STMT_FILENAME (t);
7748 add_stmt (build_nt (FILE_STMT, FILE_STMT_FILENAME_NODE (t)));
7753 tmp = GOTO_DESTINATION (t);
7754 if (TREE_CODE (tmp) != LABEL_DECL)
7755 /* Computed goto's must be tsubst'd into. On the other hand,
7756 non-computed gotos must not be; the identifier in question
7757 will have no binding. */
7758 tmp = tsubst_expr (tmp, args, complain, in_decl);
7760 tmp = DECL_NAME (tmp);
7761 finish_goto_stmt (tmp);
7766 tmp = finish_asm_stmt
7768 tsubst_expr (ASM_STRING (t), args, complain, in_decl),
7769 tsubst_expr (ASM_OUTPUTS (t), args, complain, in_decl),
7770 tsubst_expr (ASM_INPUTS (t), args, complain, in_decl),
7771 tsubst_expr (ASM_CLOBBERS (t), args, complain, in_decl));
7772 ASM_INPUT_P (tmp) = ASM_INPUT_P (t);
7779 stmt = begin_try_block ();
7780 tsubst_expr (TRY_STMTS (t), args, complain, in_decl);
7781 finish_cleanup_try_block (stmt);
7782 finish_cleanup (tsubst_expr (TRY_HANDLERS (t), args,
7788 if (FN_TRY_BLOCK_P (t))
7789 stmt = begin_function_try_block ();
7791 stmt = begin_try_block ();
7793 tsubst_expr (TRY_STMTS (t), args, complain, in_decl);
7795 if (FN_TRY_BLOCK_P (t))
7796 finish_function_try_block (stmt);
7798 finish_try_block (stmt);
7800 tsubst_expr (TRY_HANDLERS (t), args, complain, in_decl);
7801 if (FN_TRY_BLOCK_P (t))
7802 finish_function_handler_sequence (stmt);
7804 finish_handler_sequence (stmt);
7813 stmt = begin_handler ();
7814 if (HANDLER_PARMS (t))
7816 decl = DECL_STMT_DECL (HANDLER_PARMS (t));
7817 decl = tsubst (decl, args, complain, in_decl);
7818 /* Prevent instantiate_decl from trying to instantiate
7819 this variable. We've already done all that needs to be
7821 DECL_TEMPLATE_INSTANTIATED (decl) = 1;
7825 finish_handler_parms (decl, stmt);
7826 tsubst_expr (HANDLER_BODY (t), args, complain, in_decl);
7827 finish_handler (stmt);
7833 tsubst (TREE_TYPE (t), args, complain, NULL_TREE);
7840 return tsubst_expr (TREE_CHAIN (t), args, complain | stmt_expr, in_decl);
7843 /* T is a postfix-expression that is not being used in a function
7844 call. Return the substituted version of T. */
7847 tsubst_non_call_postfix_expression (tree t, tree args,
7848 tsubst_flags_t complain,
7851 if (TREE_CODE (t) == SCOPE_REF)
7852 t = tsubst_qualified_id (t, args, complain, in_decl,
7853 /*done=*/false, /*address_p=*/false);
7855 t = tsubst_copy_and_build (t, args, complain, in_decl,
7856 /*function_p=*/false);
7861 /* Like tsubst but deals with expressions and performs semantic
7862 analysis. FUNCTION_P is true if T is the "F" in "F (ARGS)". */
7865 tsubst_copy_and_build (tree t,
7867 tsubst_flags_t complain,
7871 #define RECUR(NODE) \
7872 tsubst_copy_and_build (NODE, args, complain, in_decl, /*function_p=*/false)
7876 if (t == NULL_TREE || t == error_mark_node)
7879 switch (TREE_CODE (t))
7884 case IDENTIFIER_NODE:
7888 tree qualifying_class;
7889 bool non_constant_expression_p;
7890 const char *error_msg;
7892 if (IDENTIFIER_TYPENAME_P (t))
7894 tree new_type = tsubst (TREE_TYPE (t), args, complain, in_decl);
7895 t = mangle_conv_op_name_for_type (new_type);
7898 /* Look up the name. */
7899 decl = lookup_name (t, 0);
7901 /* By convention, expressions use ERROR_MARK_NODE to indicate
7902 failure, not NULL_TREE. */
7903 if (decl == NULL_TREE)
7904 decl = error_mark_node;
7906 decl = finish_id_expression (t, decl, NULL_TREE,
7909 /*constant_expression_p=*/false,
7910 /*allow_non_constant_expression_p=*/false,
7911 &non_constant_expression_p,
7915 if (!function_p && TREE_CODE (decl) == IDENTIFIER_NODE)
7916 decl = unqualified_name_lookup_error (decl);
7920 case TEMPLATE_ID_EXPR:
7923 tree template = RECUR (TREE_OPERAND (t, 0));
7924 tree targs = TREE_OPERAND (t, 1);
7927 targs = tsubst_template_args (targs, args, complain, in_decl);
7929 if (TREE_CODE (template) == COMPONENT_REF)
7931 object = TREE_OPERAND (template, 0);
7932 template = TREE_OPERAND (template, 1);
7936 template = lookup_template_function (template, targs);
7939 return build (COMPONENT_REF, TREE_TYPE (template),
7946 return build_x_indirect_ref (RECUR (TREE_OPERAND (t, 0)), "unary *");
7949 return build_functional_cast
7950 (tsubst (TREE_TYPE (t), args, complain, in_decl),
7951 RECUR (TREE_OPERAND (t, 0)));
7953 case REINTERPRET_CAST_EXPR:
7954 return build_reinterpret_cast
7955 (tsubst (TREE_TYPE (t), args, complain, in_decl),
7956 RECUR (TREE_OPERAND (t, 0)));
7958 case CONST_CAST_EXPR:
7959 return build_const_cast
7960 (tsubst (TREE_TYPE (t), args, complain, in_decl),
7961 RECUR (TREE_OPERAND (t, 0)));
7963 case DYNAMIC_CAST_EXPR:
7964 return build_dynamic_cast
7965 (tsubst (TREE_TYPE (t), args, complain, in_decl),
7966 RECUR (TREE_OPERAND (t, 0)));
7968 case STATIC_CAST_EXPR:
7969 return build_static_cast
7970 (tsubst (TREE_TYPE (t), args, complain, in_decl),
7971 RECUR (TREE_OPERAND (t, 0)));
7973 case POSTDECREMENT_EXPR:
7974 case POSTINCREMENT_EXPR:
7975 op1 = tsubst_non_call_postfix_expression (TREE_OPERAND (t, 0),
7976 args, complain, in_decl);
7977 return build_x_unary_op (TREE_CODE (t), op1);
7979 case PREDECREMENT_EXPR:
7980 case PREINCREMENT_EXPR:
7984 case TRUTH_NOT_EXPR:
7985 case CONVERT_EXPR: /* Unary + */
7988 return build_x_unary_op (TREE_CODE (t), RECUR (TREE_OPERAND (t, 0)));
7991 op1 = TREE_OPERAND (t, 0);
7992 if (TREE_CODE (op1) == SCOPE_REF)
7993 op1 = tsubst_qualified_id (op1, args, complain, in_decl,
7994 /*done=*/true, /*address_p=*/true);
7996 op1 = tsubst_non_call_postfix_expression (op1, args, complain,
7998 if (TREE_CODE (op1) == LABEL_DECL)
7999 return finish_label_address_expr (DECL_NAME (op1));
8000 return build_x_unary_op (ADDR_EXPR, op1);
8005 case TRUNC_DIV_EXPR:
8007 case FLOOR_DIV_EXPR:
8008 case ROUND_DIV_EXPR:
8009 case EXACT_DIV_EXPR:
8013 case TRUNC_MOD_EXPR:
8014 case FLOOR_MOD_EXPR:
8015 case TRUTH_ANDIF_EXPR:
8016 case TRUTH_ORIF_EXPR:
8017 case TRUTH_AND_EXPR:
8033 return build_x_binary_op
8035 RECUR (TREE_OPERAND (t, 0)),
8036 RECUR (TREE_OPERAND (t, 1)));
8039 return tsubst_qualified_id (t, args, complain, in_decl, /*done=*/true,
8040 /*address_p=*/false);
8043 if (tsubst_copy (TREE_OPERAND (t, 0), args, complain, in_decl)
8046 return build_nt (ARRAY_REF, NULL_TREE, RECUR (TREE_OPERAND (t, 1)));
8048 op1 = tsubst_non_call_postfix_expression (TREE_OPERAND (t, 0),
8049 args, complain, in_decl);
8050 /* Remember that there was a reference to this entity. */
8053 return grok_array_decl (op1, RECUR (TREE_OPERAND (t, 1)));
8057 op1 = TREE_OPERAND (t, 0);
8060 /* When there are no ARGS, we are trying to evaluate a
8061 non-dependent expression from the parser. Trying to do
8062 the substitutions may not work. */
8064 op1 = TREE_TYPE (op1);
8073 return cxx_sizeof_or_alignof_type (op1, TREE_CODE (t), true);
8075 return cxx_sizeof_or_alignof_expr (op1, TREE_CODE (t));
8078 return build_x_modify_expr
8079 (RECUR (TREE_OPERAND (t, 0)),
8080 TREE_CODE (TREE_OPERAND (t, 1)),
8081 RECUR (TREE_OPERAND (t, 2)));
8084 op1 = tsubst_non_call_postfix_expression (TREE_OPERAND (t, 0),
8085 args, complain, in_decl);
8086 /* Remember that there was a reference to this entity. */
8089 return build_x_arrow (op1);
8093 (RECUR (TREE_OPERAND (t, 0)),
8094 RECUR (TREE_OPERAND (t, 1)),
8095 RECUR (TREE_OPERAND (t, 2)),
8096 NEW_EXPR_USE_GLOBAL (t));
8099 return delete_sanity
8100 (RECUR (TREE_OPERAND (t, 0)),
8101 RECUR (TREE_OPERAND (t, 1)),
8102 DELETE_EXPR_USE_VEC (t),
8103 DELETE_EXPR_USE_GLOBAL (t));
8106 return build_x_compound_expr (RECUR (TREE_OPERAND (t, 0)),
8107 RECUR (TREE_OPERAND (t, 1)));
8116 function = TREE_OPERAND (t, 0);
8117 /* When we parsed the expression, we determined whether or
8118 not Koenig lookup should be performed. */
8119 koenig_p = KOENIG_LOOKUP_P (t);
8120 if (TREE_CODE (function) == SCOPE_REF)
8123 function = tsubst_qualified_id (function, args, complain, in_decl,
8125 /*address_p=*/false);
8129 qualified_p = (TREE_CODE (function) == COMPONENT_REF
8130 && (TREE_CODE (TREE_OPERAND (function, 1))
8132 function = tsubst_copy_and_build (function, args, complain,
8135 if (BASELINK_P (function))
8139 call_args = RECUR (TREE_OPERAND (t, 1));
8142 && (is_overloaded_fn (function)
8143 || DECL_P (function)
8144 || TREE_CODE (function) == IDENTIFIER_NODE))
8145 function = perform_koenig_lookup (function, call_args);
8147 if (TREE_CODE (function) == IDENTIFIER_NODE)
8149 unqualified_name_lookup_error (function);
8150 return error_mark_node;
8153 /* Remember that there was a reference to this entity. */
8154 if (DECL_P (function))
8155 mark_used (function);
8157 function = convert_from_reference (function);
8159 if (TREE_CODE (function) == OFFSET_REF)
8160 return build_offset_ref_call_from_tree (function, call_args);
8161 if (TREE_CODE (function) == COMPONENT_REF)
8162 return (build_new_method_call
8163 (TREE_OPERAND (function, 0),
8164 TREE_OPERAND (function, 1),
8165 call_args, NULL_TREE,
8166 qualified_p ? LOOKUP_NONVIRTUAL : LOOKUP_NORMAL));
8167 return finish_call_expr (function, call_args,
8168 /*disallow_virtual=*/qualified_p,
8173 return build_x_conditional_expr
8174 (RECUR (TREE_OPERAND (t, 0)),
8175 RECUR (TREE_OPERAND (t, 1)),
8176 RECUR (TREE_OPERAND (t, 2)));
8178 case PSEUDO_DTOR_EXPR:
8179 return finish_pseudo_destructor_expr
8180 (RECUR (TREE_OPERAND (t, 0)),
8181 RECUR (TREE_OPERAND (t, 1)),
8182 RECUR (TREE_OPERAND (t, 2)));
8186 tree purpose, value, chain;
8188 if (t == void_list_node)
8191 purpose = TREE_PURPOSE (t);
8193 purpose = RECUR (purpose);
8194 value = TREE_VALUE (t);
8196 value = RECUR (value);
8197 chain = TREE_CHAIN (t);
8198 if (chain && chain != void_type_node)
8199 chain = RECUR (chain);
8200 if (purpose == TREE_PURPOSE (t)
8201 && value == TREE_VALUE (t)
8202 && chain == TREE_CHAIN (t))
8204 return tree_cons (purpose, value, chain);
8212 object = tsubst_non_call_postfix_expression (TREE_OPERAND (t, 0),
8213 args, complain, in_decl);
8214 /* Remember that there was a reference to this entity. */
8215 if (DECL_P (object))
8218 member = TREE_OPERAND (t, 1);
8219 if (BASELINK_P (member))
8220 member = tsubst_baselink (member,
8221 non_reference (TREE_TYPE (object)),
8222 args, complain, in_decl);
8224 member = tsubst_copy (member, args, complain, in_decl);
8226 if (!CLASS_TYPE_P (TREE_TYPE (object)))
8228 if (TREE_CODE (member) == BIT_NOT_EXPR)
8229 return finish_pseudo_destructor_expr (object,
8231 TREE_TYPE (object));
8232 else if (TREE_CODE (member) == SCOPE_REF
8233 && (TREE_CODE (TREE_OPERAND (member, 1)) == BIT_NOT_EXPR))
8234 return finish_pseudo_destructor_expr (object,
8236 TREE_TYPE (object));
8238 else if (TREE_CODE (member) == SCOPE_REF
8239 && TREE_CODE (TREE_OPERAND (member, 1)) == TEMPLATE_ID_EXPR)
8244 /* Lookup the template functions now that we know what the
8246 tmpl = TREE_OPERAND (TREE_OPERAND (member, 1), 0);
8247 args = TREE_OPERAND (TREE_OPERAND (member, 1), 1);
8248 member = lookup_qualified_name (TREE_OPERAND (member, 0), tmpl,
8249 /*is_type_p=*/false,
8250 /*complain=*/false);
8251 if (BASELINK_P (member))
8252 BASELINK_FUNCTIONS (member)
8253 = build_nt (TEMPLATE_ID_EXPR, BASELINK_FUNCTIONS (member),
8257 qualified_name_lookup_error (TREE_TYPE (object), tmpl);
8258 return error_mark_node;
8261 else if (TREE_CODE (member) == FIELD_DECL)
8262 return finish_non_static_data_member (member, object, NULL_TREE);
8264 return finish_class_member_access_expr (object, member);
8269 (RECUR (TREE_OPERAND (t, 0)));
8275 tree type = tsubst (TREE_TYPE (t), args, complain, in_decl);
8278 /* digest_init will do the wrong thing if we let it. */
8279 if (type && TYPE_PTRMEMFUNC_P (type))
8283 /* We do not want to process the purpose of aggregate
8284 initializers as they are identifier nodes which will be
8285 looked up by digest_init. */
8286 purpose_p = !(type && IS_AGGR_TYPE (type));
8287 for (elts = CONSTRUCTOR_ELTS (t);
8289 elts = TREE_CHAIN (elts))
8291 tree purpose = TREE_PURPOSE (elts);
8292 tree value = TREE_VALUE (elts);
8294 if (purpose && purpose_p)
8295 purpose = RECUR (purpose);
8296 value = RECUR (value);
8297 r = tree_cons (purpose, value, r);
8300 r = build_constructor (NULL_TREE, nreverse (r));
8301 TREE_HAS_CONSTRUCTOR (r) = TREE_HAS_CONSTRUCTOR (t);
8304 return digest_init (type, r, 0);
8310 tree operand_0 = RECUR (TREE_OPERAND (t, 0));
8311 if (TYPE_P (operand_0))
8312 return get_typeid (operand_0);
8313 return build_typeid (operand_0);
8317 return convert_from_reference (tsubst_copy (t, args, complain, in_decl));
8321 t = tsubst_copy (t, args, complain, in_decl);
8323 /* If there are no ARGS, then we are evaluating a
8324 non-dependent expression. If the expression is
8325 non-dependent, the variable must be a constant. */
8326 t = DECL_INITIAL (t);
8327 return convert_from_reference (t);
8330 return build_x_va_arg (RECUR (TREE_OPERAND (t, 0)),
8331 tsubst_copy (TREE_TYPE (t), args, complain,
8335 return tsubst_copy (t, args, complain, in_decl);
8341 /* Verify that the instantiated ARGS are valid. For type arguments,
8342 make sure that the type's linkage is ok. For non-type arguments,
8343 make sure they are constants if they are integral or enumerations.
8344 Emit an error under control of COMPLAIN, and return TRUE on error. */
8347 check_instantiated_args (tree tmpl, tree args, tsubst_flags_t complain)
8349 int ix, len = DECL_NTPARMS (tmpl);
8350 bool result = false;
8352 for (ix = 0; ix != len; ix++)
8354 tree t = TREE_VEC_ELT (args, ix);
8358 /* [basic.link]: A name with no linkage (notably, the name
8359 of a class or enumeration declared in a local scope)
8360 shall not be used to declare an entity with linkage.
8361 This implies that names with no linkage cannot be used as
8362 template arguments. */
8363 tree nt = no_linkage_check (t);
8367 if (!(complain & tf_error))
8369 else if (TYPE_ANONYMOUS_P (nt))
8370 error ("`%T' uses anonymous type", t);
8372 error ("`%T' uses local type `%T'", t, nt);
8375 /* In order to avoid all sorts of complications, we do not
8376 allow variably-modified types as template arguments. */
8377 else if (variably_modified_type_p (t))
8379 if (complain & tf_error)
8380 error ("`%T' is a variably modified type", t);
8384 /* A non-type argument of integral or enumerated type must be a
8386 else if (TREE_TYPE (t)
8387 && INTEGRAL_OR_ENUMERATION_TYPE_P (TREE_TYPE (t))
8388 && !TREE_CONSTANT (t))
8390 if (complain & tf_error)
8391 error ("integral expression `%E' is not constant", t);
8395 if (result && complain & tf_error)
8396 error (" trying to instantiate `%D'", tmpl);
8400 /* Instantiate the indicated variable or function template TMPL with
8401 the template arguments in TARG_PTR. */
8404 instantiate_template (tree tmpl, tree targ_ptr, tsubst_flags_t complain)
8410 if (tmpl == error_mark_node)
8411 return error_mark_node;
8413 my_friendly_assert (TREE_CODE (tmpl) == TEMPLATE_DECL, 283);
8415 /* If this function is a clone, handle it specially. */
8416 if (DECL_CLONED_FUNCTION_P (tmpl))
8418 tree spec = instantiate_template (DECL_CLONED_FUNCTION (tmpl), targ_ptr,
8422 /* Look for the clone. */
8423 for (clone = TREE_CHAIN (spec);
8424 clone && DECL_CLONED_FUNCTION_P (clone);
8425 clone = TREE_CHAIN (clone))
8426 if (DECL_NAME (clone) == DECL_NAME (tmpl))
8428 /* We should always have found the clone by now. */
8433 /* Check to see if we already have this specialization. */
8434 spec = retrieve_specialization (tmpl, targ_ptr);
8435 if (spec != NULL_TREE)
8438 gen_tmpl = most_general_template (tmpl);
8439 if (tmpl != gen_tmpl)
8441 /* The TMPL is a partial instantiation. To get a full set of
8442 arguments we must add the arguments used to perform the
8443 partial instantiation. */
8444 targ_ptr = add_outermost_template_args (DECL_TI_ARGS (tmpl),
8447 /* Check to see if we already have this specialization. */
8448 spec = retrieve_specialization (gen_tmpl, targ_ptr);
8449 if (spec != NULL_TREE)
8453 if (check_instantiated_args (gen_tmpl, INNERMOST_TEMPLATE_ARGS (targ_ptr),
8455 return error_mark_node;
8457 /* We are building a FUNCTION_DECL, during which the access of its
8458 parameters and return types have to be checked. However this
8459 FUNCTION_DECL which is the desired context for access checking
8460 is not built yet. We solve this chicken-and-egg problem by
8461 deferring all checks until we have the FUNCTION_DECL. */
8462 push_deferring_access_checks (dk_deferred);
8464 /* substitute template parameters */
8465 fndecl = tsubst (DECL_TEMPLATE_RESULT (gen_tmpl),
8466 targ_ptr, complain, gen_tmpl);
8468 /* Now we know the specialization, compute access previously
8470 push_access_scope (fndecl);
8471 perform_deferred_access_checks ();
8472 pop_access_scope (fndecl);
8473 pop_deferring_access_checks ();
8475 /* The DECL_TI_TEMPLATE should always be the immediate parent
8476 template, not the most general template. */
8477 DECL_TI_TEMPLATE (fndecl) = tmpl;
8479 if (flag_external_templates)
8480 add_pending_template (fndecl);
8482 /* If we've just instantiated the main entry point for a function,
8483 instantiate all the alternate entry points as well. We do this
8484 by cloning the instantiation of the main entry point, not by
8485 instantiating the template clones. */
8486 if (TREE_CHAIN (gen_tmpl) && DECL_CLONED_FUNCTION_P (TREE_CHAIN (gen_tmpl)))
8487 clone_function_decl (fndecl, /*update_method_vec_p=*/0);
8492 /* The FN is a TEMPLATE_DECL for a function. The ARGS are the
8493 arguments that are being used when calling it. TARGS is a vector
8494 into which the deduced template arguments are placed.
8496 Return zero for success, 2 for an incomplete match that doesn't resolve
8497 all the types, and 1 for complete failure. An error message will be
8498 printed only for an incomplete match.
8500 If FN is a conversion operator, or we are trying to produce a specific
8501 specialization, RETURN_TYPE is the return type desired.
8503 The EXPLICIT_TARGS are explicit template arguments provided via a
8506 The parameter STRICT is one of:
8509 We are deducing arguments for a function call, as in
8513 We are deducing arguments for a conversion function, as in
8517 We are deducing arguments when doing an explicit instantiation
8518 as in [temp.explicit], when determining an explicit specialization
8519 as in [temp.expl.spec], or when taking the address of a function
8520 template, as in [temp.deduct.funcaddr].
8523 We are deducing arguments when calculating the partial
8524 ordering between specializations of function or class
8525 templates, as in [temp.func.order] and [temp.class.order].
8527 LEN is the number of parms to consider before returning success, or -1
8528 for all. This is used in partial ordering to avoid comparing parms for
8529 which no actual argument was passed, since they are not considered in
8530 overload resolution (and are explicitly excluded from consideration in
8531 partial ordering in [temp.func.order]/6). */
8534 fn_type_unification (tree fn,
8535 tree explicit_targs,
8539 unification_kind_t strict,
8546 my_friendly_assert (TREE_CODE (fn) == TEMPLATE_DECL, 0);
8548 fntype = TREE_TYPE (fn);
8553 The specified template arguments must match the template
8554 parameters in kind (i.e., type, nontype, template), and there
8555 must not be more arguments than there are parameters;
8556 otherwise type deduction fails.
8558 Nontype arguments must match the types of the corresponding
8559 nontype template parameters, or must be convertible to the
8560 types of the corresponding nontype parameters as specified in
8561 _temp.arg.nontype_, otherwise type deduction fails.
8563 All references in the function type of the function template
8564 to the corresponding template parameters are replaced by the
8565 specified template argument values. If a substitution in a
8566 template parameter or in the function type of the function
8567 template results in an invalid type, type deduction fails. */
8569 tree converted_args;
8573 = (coerce_template_parms (DECL_INNERMOST_TEMPLATE_PARMS (fn),
8574 explicit_targs, NULL_TREE, tf_none,
8575 /*require_all_arguments=*/0));
8576 if (converted_args == error_mark_node)
8579 /* Substitute the explicit args into the function type. This is
8580 necessary so that, for instance, explicitly declared function
8581 arguments can match null pointed constants. If we were given
8582 an incomplete set of explicit args, we must not do semantic
8583 processing during substitution as we could create partial
8585 incomplete = NUM_TMPL_ARGS (explicit_targs) != NUM_TMPL_ARGS (targs);
8586 processing_template_decl += incomplete;
8587 fntype = tsubst (fntype, converted_args, tf_none, NULL_TREE);
8588 processing_template_decl -= incomplete;
8590 if (fntype == error_mark_node)
8593 /* Place the explicitly specified arguments in TARGS. */
8594 for (i = NUM_TMPL_ARGS (converted_args); i--;)
8595 TREE_VEC_ELT (targs, i) = TREE_VEC_ELT (converted_args, i);
8598 parms = TYPE_ARG_TYPES (fntype);
8599 /* Never do unification on the 'this' parameter. */
8600 if (DECL_NONSTATIC_MEMBER_FUNCTION_P (fn))
8601 parms = TREE_CHAIN (parms);
8605 /* We've been given a return type to match, prepend it. */
8606 parms = tree_cons (NULL_TREE, TREE_TYPE (fntype), parms);
8607 args = tree_cons (NULL_TREE, return_type, args);
8612 /* We allow incomplete unification without an error message here
8613 because the standard doesn't seem to explicitly prohibit it. Our
8614 callers must be ready to deal with unification failures in any
8616 result = type_unification_real (DECL_INNERMOST_TEMPLATE_PARMS (fn),
8617 targs, parms, args, /*subr=*/0,
8618 strict, /*allow_incomplete*/1, len);
8621 /* All is well so far. Now, check:
8625 When all template arguments have been deduced, all uses of
8626 template parameters in nondeduced contexts are replaced with
8627 the corresponding deduced argument values. If the
8628 substitution results in an invalid type, as described above,
8629 type deduction fails. */
8630 if (tsubst (TREE_TYPE (fn), targs, tf_none, NULL_TREE)
8637 /* Adjust types before performing type deduction, as described in
8638 [temp.deduct.call] and [temp.deduct.conv]. The rules in these two
8639 sections are symmetric. PARM is the type of a function parameter
8640 or the return type of the conversion function. ARG is the type of
8641 the argument passed to the call, or the type of the value
8642 initialized with the result of the conversion function. */
8645 maybe_adjust_types_for_deduction (unification_kind_t strict,
8658 /* Swap PARM and ARG throughout the remainder of this
8659 function; the handling is precisely symmetric since PARM
8660 will initialize ARG rather than vice versa. */
8668 /* There is nothing to do in this case. */
8672 /* DR 214. [temp.func.order] is underspecified, and leads to no
8673 ordering between things like `T *' and `T const &' for `U *'.
8674 The former has T=U and the latter T=U*. The former looks more
8675 specialized and John Spicer considers it well-formed (the EDG
8676 compiler accepts it).
8678 John also confirms that deduction should proceed as in a function
8679 call. Which implies the usual ARG and PARM conversions as DEDUCE_CALL.
8680 However, in ordering, ARG can have REFERENCE_TYPE, but no argument
8681 to an actual call can have such a type.
8683 If both ARG and PARM are REFERENCE_TYPE, we change neither.
8684 If only ARG is a REFERENCE_TYPE, we look through that and then
8685 proceed as with DEDUCE_CALL (which could further convert it). */
8686 if (TREE_CODE (*arg) == REFERENCE_TYPE)
8688 if (TREE_CODE (*parm) == REFERENCE_TYPE)
8690 *arg = TREE_TYPE (*arg);
8697 if (TREE_CODE (*parm) != REFERENCE_TYPE)
8699 /* [temp.deduct.call]
8701 If P is not a reference type:
8703 --If A is an array type, the pointer type produced by the
8704 array-to-pointer standard conversion (_conv.array_) is
8705 used in place of A for type deduction; otherwise,
8707 --If A is a function type, the pointer type produced by
8708 the function-to-pointer standard conversion
8709 (_conv.func_) is used in place of A for type deduction;
8712 --If A is a cv-qualified type, the top level
8713 cv-qualifiers of A's type are ignored for type
8715 if (TREE_CODE (*arg) == ARRAY_TYPE)
8716 *arg = build_pointer_type (TREE_TYPE (*arg));
8717 else if (TREE_CODE (*arg) == FUNCTION_TYPE)
8718 *arg = build_pointer_type (*arg);
8720 *arg = TYPE_MAIN_VARIANT (*arg);
8723 /* [temp.deduct.call]
8725 If P is a cv-qualified type, the top level cv-qualifiers
8726 of P's type are ignored for type deduction. If P is a
8727 reference type, the type referred to by P is used for
8729 *parm = TYPE_MAIN_VARIANT (*parm);
8730 if (TREE_CODE (*parm) == REFERENCE_TYPE)
8732 *parm = TREE_TYPE (*parm);
8733 result |= UNIFY_ALLOW_OUTER_MORE_CV_QUAL;
8736 /* DR 322. For conversion deduction, remove a reference type on parm
8737 too (which has been swapped into ARG). */
8738 if (strict == DEDUCE_CONV && TREE_CODE (*arg) == REFERENCE_TYPE)
8739 *arg = TREE_TYPE (*arg);
8744 /* Most parms like fn_type_unification.
8746 If SUBR is 1, we're being called recursively (to unify the
8747 arguments of a function or method parameter of a function
8751 type_unification_real (tree tparms,
8756 unification_kind_t strict,
8757 int allow_incomplete,
8762 int ntparms = TREE_VEC_LENGTH (tparms);
8764 int saw_undeduced = 0;
8768 my_friendly_assert (TREE_CODE (tparms) == TREE_VEC, 289);
8769 my_friendly_assert (xparms == NULL_TREE
8770 || TREE_CODE (xparms) == TREE_LIST, 290);
8771 my_friendly_assert (!xargs || TREE_CODE (xargs) == TREE_LIST, 291);
8772 my_friendly_assert (ntparms > 0, 292);
8777 sub_strict = (UNIFY_ALLOW_OUTER_LEVEL | UNIFY_ALLOW_MORE_CV_QUAL
8778 | UNIFY_ALLOW_DERIVED);
8782 sub_strict = UNIFY_ALLOW_LESS_CV_QUAL;
8786 sub_strict = UNIFY_ALLOW_NONE;
8790 sub_strict = UNIFY_ALLOW_NONE;
8806 && parms != void_list_node
8808 && args != void_list_node)
8810 parm = TREE_VALUE (parms);
8811 parms = TREE_CHAIN (parms);
8812 arg = TREE_VALUE (args);
8813 args = TREE_CHAIN (args);
8815 if (arg == error_mark_node)
8817 if (arg == unknown_type_node)
8818 /* We can't deduce anything from this, but we might get all the
8819 template args from other function args. */
8822 /* Conversions will be performed on a function argument that
8823 corresponds with a function parameter that contains only
8824 non-deducible template parameters and explicitly specified
8825 template parameters. */
8826 if (! uses_template_parms (parm))
8831 type = TREE_TYPE (arg);
8838 if (strict == DEDUCE_EXACT || strict == DEDUCE_ORDER)
8840 if (same_type_p (parm, type))
8844 /* It might work; we shouldn't check now, because we might
8845 get into infinite recursion. Overload resolution will
8854 my_friendly_assert (TREE_TYPE (arg) != NULL_TREE, 293);
8855 if (type_unknown_p (arg))
8857 /* [temp.deduct.type] A template-argument can be deduced from
8858 a pointer to function or pointer to member function
8859 argument if the set of overloaded functions does not
8860 contain function templates and at most one of a set of
8861 overloaded functions provides a unique match. */
8863 if (resolve_overloaded_unification
8864 (tparms, targs, parm, arg, strict, sub_strict)
8869 arg = TREE_TYPE (arg);
8870 if (arg == error_mark_node)
8875 int arg_strict = sub_strict;
8878 arg_strict |= maybe_adjust_types_for_deduction (strict, &parm, &arg);
8880 if (unify (tparms, targs, parm, arg, arg_strict))
8884 /* Are we done with the interesting parms? */
8888 /* Fail if we've reached the end of the parm list, and more args
8889 are present, and the parm list isn't variadic. */
8890 if (args && args != void_list_node && parms == void_list_node)
8892 /* Fail if parms are left and they don't have default values. */
8894 && parms != void_list_node
8895 && TREE_PURPOSE (parms) == NULL_TREE)
8900 for (i = 0; i < ntparms; i++)
8901 if (TREE_VEC_ELT (targs, i) == NULL_TREE)
8903 tree tparm = TREE_VALUE (TREE_VEC_ELT (tparms, i));
8905 /* If this is an undeduced nontype parameter that depends on
8906 a type parameter, try another pass; its type may have been
8907 deduced from a later argument than the one from which
8908 this parameter can be deduced. */
8909 if (TREE_CODE (tparm) == PARM_DECL
8910 && uses_template_parms (TREE_TYPE (tparm))
8911 && !saw_undeduced++)
8914 if (!allow_incomplete)
8915 error ("incomplete type unification");
8921 /* Subroutine of type_unification_real. Args are like the variables at the
8922 call site. ARG is an overloaded function (or template-id); we try
8923 deducing template args from each of the overloads, and if only one
8924 succeeds, we go with that. Modifies TARGS and returns 0 on success. */
8927 resolve_overloaded_unification (tree tparms,
8931 unification_kind_t strict,
8934 tree tempargs = copy_node (targs);
8938 if (TREE_CODE (arg) == ADDR_EXPR)
8940 arg = TREE_OPERAND (arg, 0);
8946 if (TREE_CODE (arg) == COMPONENT_REF)
8947 /* Handle `&x' where `x' is some static or non-static member
8949 arg = TREE_OPERAND (arg, 1);
8951 if (TREE_CODE (arg) == OFFSET_REF)
8952 arg = TREE_OPERAND (arg, 1);
8954 /* Strip baselink information. */
8955 if (BASELINK_P (arg))
8956 arg = BASELINK_FUNCTIONS (arg);
8958 if (TREE_CODE (arg) == TEMPLATE_ID_EXPR)
8960 /* If we got some explicit template args, we need to plug them into
8961 the affected templates before we try to unify, in case the
8962 explicit args will completely resolve the templates in question. */
8964 tree expl_subargs = TREE_OPERAND (arg, 1);
8965 arg = TREE_OPERAND (arg, 0);
8967 for (; arg; arg = OVL_NEXT (arg))
8969 tree fn = OVL_CURRENT (arg);
8972 if (TREE_CODE (fn) != TEMPLATE_DECL)
8975 subargs = get_bindings_overload (fn, DECL_TEMPLATE_RESULT (fn),
8979 elem = tsubst (TREE_TYPE (fn), subargs, tf_none, NULL_TREE);
8980 good += try_one_overload (tparms, targs, tempargs, parm,
8981 elem, strict, sub_strict, addr_p);
8985 else if (TREE_CODE (arg) == OVERLOAD
8986 || TREE_CODE (arg) == FUNCTION_DECL)
8988 for (; arg; arg = OVL_NEXT (arg))
8989 good += try_one_overload (tparms, targs, tempargs, parm,
8990 TREE_TYPE (OVL_CURRENT (arg)),
8991 strict, sub_strict, addr_p);
8996 /* [temp.deduct.type] A template-argument can be deduced from a pointer
8997 to function or pointer to member function argument if the set of
8998 overloaded functions does not contain function templates and at most
8999 one of a set of overloaded functions provides a unique match.
9001 So if we found multiple possibilities, we return success but don't
9006 int i = TREE_VEC_LENGTH (targs);
9008 if (TREE_VEC_ELT (tempargs, i))
9009 TREE_VEC_ELT (targs, i) = TREE_VEC_ELT (tempargs, i);
9017 /* Subroutine of resolve_overloaded_unification; does deduction for a single
9018 overload. Fills TARGS with any deduced arguments, or error_mark_node if
9019 different overloads deduce different arguments for a given parm.
9020 ADDR_P is true if the expression for which deduction is being
9021 performed was of the form "& fn" rather than simply "fn".
9023 Returns 1 on success. */
9026 try_one_overload (tree tparms,
9031 unification_kind_t strict,
9039 /* [temp.deduct.type] A template-argument can be deduced from a pointer
9040 to function or pointer to member function argument if the set of
9041 overloaded functions does not contain function templates and at most
9042 one of a set of overloaded functions provides a unique match.
9044 So if this is a template, just return success. */
9046 if (uses_template_parms (arg))
9049 if (TREE_CODE (arg) == METHOD_TYPE)
9050 arg = build_ptrmemfunc_type (build_pointer_type (arg));
9052 arg = build_pointer_type (arg);
9054 sub_strict |= maybe_adjust_types_for_deduction (strict, &parm, &arg);
9056 /* We don't copy orig_targs for this because if we have already deduced
9057 some template args from previous args, unify would complain when we
9058 try to deduce a template parameter for the same argument, even though
9059 there isn't really a conflict. */
9060 nargs = TREE_VEC_LENGTH (targs);
9061 tempargs = make_tree_vec (nargs);
9063 if (unify (tparms, tempargs, parm, arg, sub_strict) != 0)
9066 /* First make sure we didn't deduce anything that conflicts with
9067 explicitly specified args. */
9068 for (i = nargs; i--; )
9070 tree elt = TREE_VEC_ELT (tempargs, i);
9071 tree oldelt = TREE_VEC_ELT (orig_targs, i);
9073 if (elt == NULL_TREE)
9075 else if (uses_template_parms (elt))
9077 /* Since we're unifying against ourselves, we will fill in template
9078 args used in the function parm list with our own template parms.
9080 TREE_VEC_ELT (tempargs, i) = NULL_TREE;
9083 else if (oldelt && ! template_args_equal (oldelt, elt))
9087 for (i = nargs; i--; )
9089 tree elt = TREE_VEC_ELT (tempargs, i);
9092 TREE_VEC_ELT (targs, i) = elt;
9098 /* Verify that nondeduce template argument agrees with the type
9099 obtained from argument deduction. Return nonzero if the
9104 struct A { typedef int X; };
9105 template <class T, class U> struct C {};
9106 template <class T> struct C<T, typename T::X> {};
9108 Then with the instantiation `C<A, int>', we can deduce that
9109 `T' is `A' but unify () does not check whether `typename T::X'
9110 is `int'. This function ensure that they agree.
9112 TARGS, PARMS are the same as the arguments of unify.
9113 ARGS contains template arguments from all levels. */
9116 verify_class_unification (tree targs, tree parms, tree args)
9118 parms = tsubst (parms, add_outermost_template_args (args, targs),
9119 tf_none, NULL_TREE);
9120 if (parms == error_mark_node)
9123 return !comp_template_args (parms, INNERMOST_TEMPLATE_ARGS (args));
9126 /* PARM is a template class (perhaps with unbound template
9127 parameters). ARG is a fully instantiated type. If ARG can be
9128 bound to PARM, return ARG, otherwise return NULL_TREE. TPARMS and
9129 TARGS are as for unify. */
9132 try_class_unification (tree tparms, tree targs, tree parm, tree arg)
9136 if (!CLASSTYPE_TEMPLATE_INFO (arg)
9137 || (most_general_template (CLASSTYPE_TI_TEMPLATE (arg))
9138 != most_general_template (CLASSTYPE_TI_TEMPLATE (parm))))
9141 /* We need to make a new template argument vector for the call to
9142 unify. If we used TARGS, we'd clutter it up with the result of
9143 the attempted unification, even if this class didn't work out.
9144 We also don't want to commit ourselves to all the unifications
9145 we've already done, since unification is supposed to be done on
9146 an argument-by-argument basis. In other words, consider the
9147 following pathological case:
9149 template <int I, int J, int K>
9152 template <int I, int J>
9153 struct S<I, J, 2> : public S<I, I, I>, S<J, J, J> {};
9155 template <int I, int J, int K>
9156 void f(S<I, J, K>, S<I, I, I>);
9165 Now, by the time we consider the unification involving `s2', we
9166 already know that we must have `f<0, 0, 0>'. But, even though
9167 `S<0, 1, 2>' is derived from `S<0, 0, 0>', the code is invalid
9168 because there are two ways to unify base classes of S<0, 1, 2>
9169 with S<I, I, I>. If we kept the already deduced knowledge, we
9170 would reject the possibility I=1. */
9171 copy_of_targs = make_tree_vec (TREE_VEC_LENGTH (targs));
9173 /* If unification failed, we're done. */
9174 if (unify (tparms, copy_of_targs, CLASSTYPE_TI_ARGS (parm),
9175 CLASSTYPE_TI_ARGS (arg), UNIFY_ALLOW_NONE))
9181 /* Subroutine of get_template_base. RVAL, if non-NULL, is a base we
9182 have already discovered to be satisfactory. ARG_BINFO is the binfo
9183 for the base class of ARG that we are currently examining. */
9186 get_template_base_recursive (tree tparms,
9195 tree arg = BINFO_TYPE (arg_binfo);
9197 if (!(flags & GTB_IGNORE_TYPE))
9199 tree r = try_class_unification (tparms, targs,
9202 /* If there is more than one satisfactory baseclass, then:
9206 If they yield more than one possible deduced A, the type
9210 if (r && rval && !same_type_p (r, rval))
9211 return error_mark_node;
9216 binfos = BINFO_BASETYPES (arg_binfo);
9217 n_baselinks = binfos ? TREE_VEC_LENGTH (binfos) : 0;
9219 /* Process base types. */
9220 for (i = 0; i < n_baselinks; i++)
9222 tree base_binfo = TREE_VEC_ELT (binfos, i);
9225 /* Skip this base, if we've already seen it. */
9226 if (BINFO_MARKED (base_binfo))
9230 (flags & GTB_VIA_VIRTUAL) || TREE_VIA_VIRTUAL (base_binfo);
9232 /* When searching for a non-virtual, we cannot mark virtually
9235 BINFO_MARKED (base_binfo) = 1;
9237 rval = get_template_base_recursive (tparms, targs,
9241 GTB_VIA_VIRTUAL * this_virtual);
9243 /* If we discovered more than one matching base class, we can
9245 if (rval == error_mark_node)
9246 return error_mark_node;
9252 /* Given a template type PARM and a class type ARG, find the unique
9253 base type in ARG that is an instance of PARM. We do not examine
9254 ARG itself; only its base-classes. If there is no appropriate base
9255 class, return NULL_TREE. If there is more than one, return
9256 error_mark_node. PARM may be the type of a partial specialization,
9257 as well as a plain template type. Used by unify. */
9260 get_template_base (tree tparms, tree targs, tree parm, tree arg)
9265 my_friendly_assert (IS_AGGR_TYPE_CODE (TREE_CODE (arg)), 92);
9267 arg_binfo = TYPE_BINFO (complete_type (arg));
9268 rval = get_template_base_recursive (tparms, targs,
9273 /* Since get_template_base_recursive marks the bases classes, we
9274 must unmark them here. */
9275 dfs_walk (arg_binfo, dfs_unmark, markedp, 0);
9280 /* Returns the level of DECL, which declares a template parameter. */
9283 template_decl_level (tree decl)
9285 switch (TREE_CODE (decl))
9289 return TEMPLATE_TYPE_LEVEL (TREE_TYPE (decl));
9292 return TEMPLATE_PARM_LEVEL (DECL_INITIAL (decl));
9300 /* Decide whether ARG can be unified with PARM, considering only the
9301 cv-qualifiers of each type, given STRICT as documented for unify.
9302 Returns nonzero iff the unification is OK on that basis.*/
9305 check_cv_quals_for_unify (int strict, tree arg, tree parm)
9307 int arg_quals = cp_type_quals (arg);
9308 int parm_quals = cp_type_quals (parm);
9310 if (TREE_CODE (parm) == TEMPLATE_TYPE_PARM)
9312 /* If the cvr quals of parm will not unify with ARG, they'll be
9313 ignored in instantiation, so we have to do the same here. */
9314 if (TREE_CODE (arg) == REFERENCE_TYPE)
9315 parm_quals &= ~(TYPE_QUAL_CONST | TYPE_QUAL_VOLATILE);
9316 if (!POINTER_TYPE_P (arg) &&
9317 TREE_CODE (arg) != TEMPLATE_TYPE_PARM)
9318 parm_quals &= ~TYPE_QUAL_RESTRICT;
9321 if (!(strict & (UNIFY_ALLOW_MORE_CV_QUAL | UNIFY_ALLOW_OUTER_MORE_CV_QUAL))
9322 && (arg_quals & parm_quals) != parm_quals)
9325 if (!(strict & (UNIFY_ALLOW_LESS_CV_QUAL | UNIFY_ALLOW_OUTER_LESS_CV_QUAL))
9326 && (parm_quals & arg_quals) != arg_quals)
9332 /* Takes parameters as for type_unification. Returns 0 if the
9333 type deduction succeeds, 1 otherwise. The parameter STRICT is a
9334 bitwise or of the following flags:
9337 Require an exact match between PARM and ARG.
9338 UNIFY_ALLOW_MORE_CV_QUAL:
9339 Allow the deduced ARG to be more cv-qualified (by qualification
9340 conversion) than ARG.
9341 UNIFY_ALLOW_LESS_CV_QUAL:
9342 Allow the deduced ARG to be less cv-qualified than ARG.
9343 UNIFY_ALLOW_DERIVED:
9344 Allow the deduced ARG to be a template base class of ARG,
9345 or a pointer to a template base class of the type pointed to by
9347 UNIFY_ALLOW_INTEGER:
9348 Allow any integral type to be deduced. See the TEMPLATE_PARM_INDEX
9349 case for more information.
9350 UNIFY_ALLOW_OUTER_LEVEL:
9351 This is the outermost level of a deduction. Used to determine validity
9352 of qualification conversions. A valid qualification conversion must
9353 have const qualified pointers leading up to the inner type which
9354 requires additional CV quals, except at the outer level, where const
9355 is not required [conv.qual]. It would be normal to set this flag in
9356 addition to setting UNIFY_ALLOW_MORE_CV_QUAL.
9357 UNIFY_ALLOW_OUTER_MORE_CV_QUAL:
9358 This is the outermost level of a deduction, and PARM can be more CV
9359 qualified at this point.
9360 UNIFY_ALLOW_OUTER_LESS_CV_QUAL:
9361 This is the outermost level of a deduction, and PARM can be less CV
9362 qualified at this point.
9363 UNIFY_ALLOW_MAX_CORRECTION:
9364 This is an INTEGER_TYPE's maximum value. Used if the range may
9365 have been derived from a size specification, such as an array size.
9366 If the size was given by a nontype template parameter N, the maximum
9367 value will have the form N-1. The flag says that we can (and indeed
9368 must) unify N with (ARG + 1), an exception to the normal rules on
9372 unify (tree tparms, tree targs, tree parm, tree arg, int strict)
9377 int strict_in = strict;
9379 /* I don't think this will do the right thing with respect to types.
9380 But the only case I've seen it in so far has been array bounds, where
9381 signedness is the only information lost, and I think that will be
9383 while (TREE_CODE (parm) == NOP_EXPR)
9384 parm = TREE_OPERAND (parm, 0);
9386 if (arg == error_mark_node)
9388 if (arg == unknown_type_node)
9389 /* We can't deduce anything from this, but we might get all the
9390 template args from other function args. */
9393 /* If PARM uses template parameters, then we can't bail out here,
9394 even if ARG == PARM, since we won't record unifications for the
9395 template parameters. We might need them if we're trying to
9396 figure out which of two things is more specialized. */
9397 if (arg == parm && !uses_template_parms (parm))
9400 /* Immediately reject some pairs that won't unify because of
9401 cv-qualification mismatches. */
9402 if (TREE_CODE (arg) == TREE_CODE (parm)
9404 /* It is the elements of the array which hold the cv quals of an array
9405 type, and the elements might be template type parms. We'll check
9407 && TREE_CODE (arg) != ARRAY_TYPE
9408 /* We check the cv-qualifiers when unifying with template type
9409 parameters below. We want to allow ARG `const T' to unify with
9410 PARM `T' for example, when computing which of two templates
9411 is more specialized, for example. */
9412 && TREE_CODE (arg) != TEMPLATE_TYPE_PARM
9413 && !check_cv_quals_for_unify (strict_in, arg, parm))
9416 if (!(strict & UNIFY_ALLOW_OUTER_LEVEL)
9417 && TYPE_P (parm) && !CP_TYPE_CONST_P (parm))
9418 strict &= ~UNIFY_ALLOW_MORE_CV_QUAL;
9419 strict &= ~UNIFY_ALLOW_OUTER_LEVEL;
9420 strict &= ~UNIFY_ALLOW_DERIVED;
9421 strict &= ~UNIFY_ALLOW_OUTER_MORE_CV_QUAL;
9422 strict &= ~UNIFY_ALLOW_OUTER_LESS_CV_QUAL;
9423 strict &= ~UNIFY_ALLOW_MAX_CORRECTION;
9425 switch (TREE_CODE (parm))
9429 case UNBOUND_CLASS_TEMPLATE:
9430 /* In a type which contains a nested-name-specifier, template
9431 argument values cannot be deduced for template parameters used
9432 within the nested-name-specifier. */
9435 case TEMPLATE_TYPE_PARM:
9436 case TEMPLATE_TEMPLATE_PARM:
9437 case BOUND_TEMPLATE_TEMPLATE_PARM:
9438 tparm = TREE_VALUE (TREE_VEC_ELT (tparms, 0));
9440 if (TEMPLATE_TYPE_LEVEL (parm)
9441 != template_decl_level (tparm))
9442 /* The PARM is not one we're trying to unify. Just check
9443 to see if it matches ARG. */
9444 return (TREE_CODE (arg) == TREE_CODE (parm)
9445 && same_type_p (parm, arg)) ? 0 : 1;
9446 idx = TEMPLATE_TYPE_IDX (parm);
9447 targ = TREE_VEC_ELT (targs, idx);
9448 tparm = TREE_VALUE (TREE_VEC_ELT (tparms, idx));
9450 /* Check for mixed types and values. */
9451 if ((TREE_CODE (parm) == TEMPLATE_TYPE_PARM
9452 && TREE_CODE (tparm) != TYPE_DECL)
9453 || (TREE_CODE (parm) == TEMPLATE_TEMPLATE_PARM
9454 && TREE_CODE (tparm) != TEMPLATE_DECL))
9457 if (TREE_CODE (parm) == BOUND_TEMPLATE_TEMPLATE_PARM)
9459 /* ARG must be constructed from a template class or a template
9460 template parameter. */
9461 if (TREE_CODE (arg) != BOUND_TEMPLATE_TEMPLATE_PARM
9462 && (TREE_CODE (arg) != RECORD_TYPE || !CLASSTYPE_TEMPLATE_INFO (arg)))
9466 tree parmtmpl = TYPE_TI_TEMPLATE (parm);
9467 tree parmvec = TYPE_TI_ARGS (parm);
9468 tree argvec = TYPE_TI_ARGS (arg);
9470 = DECL_INNERMOST_TEMPLATE_PARMS (TYPE_TI_TEMPLATE (arg));
9473 /* The parameter and argument roles have to be switched here
9474 in order to handle default arguments properly. For example,
9475 template<template <class> class TT> void f(TT<int>)
9476 should be able to accept vector<int> which comes from
9477 template <class T, class Allocator = allocator>
9480 if (coerce_template_parms (argtmplvec, parmvec, parmtmpl, 0, 1)
9484 /* Deduce arguments T, i from TT<T> or TT<i>.
9485 We check each element of PARMVEC and ARGVEC individually
9486 rather than the whole TREE_VEC since they can have
9487 different number of elements. */
9489 for (i = 0; i < TREE_VEC_LENGTH (parmvec); ++i)
9491 tree t = TREE_VEC_ELT (parmvec, i);
9493 if (unify (tparms, targs, t,
9494 TREE_VEC_ELT (argvec, i),
9499 arg = TYPE_TI_TEMPLATE (arg);
9501 /* Fall through to deduce template name. */
9504 if (TREE_CODE (parm) == TEMPLATE_TEMPLATE_PARM
9505 || TREE_CODE (parm) == BOUND_TEMPLATE_TEMPLATE_PARM)
9507 /* Deduce template name TT from TT, TT<>, TT<T> and TT<i>. */
9509 /* Simple cases: Value already set, does match or doesn't. */
9510 if (targ != NULL_TREE && template_args_equal (targ, arg))
9517 /* If PARM is `const T' and ARG is only `int', we don't have
9518 a match unless we are allowing additional qualification.
9519 If ARG is `const int' and PARM is just `T' that's OK;
9520 that binds `const int' to `T'. */
9521 if (!check_cv_quals_for_unify (strict_in | UNIFY_ALLOW_LESS_CV_QUAL,
9525 /* Consider the case where ARG is `const volatile int' and
9526 PARM is `const T'. Then, T should be `volatile int'. */
9527 arg = cp_build_qualified_type_real
9528 (arg, cp_type_quals (arg) & ~cp_type_quals (parm), tf_none);
9529 if (arg == error_mark_node)
9532 /* Simple cases: Value already set, does match or doesn't. */
9533 if (targ != NULL_TREE && same_type_p (targ, arg))
9538 /* Make sure that ARG is not a variable-sized array. (Note
9539 that were talking about variable-sized arrays (like
9540 `int[n]'), rather than arrays of unknown size (like
9541 `int[]').) We'll get very confused by such a type since
9542 the bound of the array will not be computable in an
9543 instantiation. Besides, such types are not allowed in
9544 ISO C++, so we can do as we please here. */
9545 if (variably_modified_type_p (arg))
9549 TREE_VEC_ELT (targs, idx) = arg;
9552 case TEMPLATE_PARM_INDEX:
9553 tparm = TREE_VALUE (TREE_VEC_ELT (tparms, 0));
9555 if (TEMPLATE_PARM_LEVEL (parm)
9556 != template_decl_level (tparm))
9557 /* The PARM is not one we're trying to unify. Just check
9558 to see if it matches ARG. */
9559 return !(TREE_CODE (arg) == TREE_CODE (parm)
9560 && cp_tree_equal (parm, arg));
9562 idx = TEMPLATE_PARM_IDX (parm);
9563 targ = TREE_VEC_ELT (targs, idx);
9566 return !cp_tree_equal (targ, arg);
9568 /* [temp.deduct.type] If, in the declaration of a function template
9569 with a non-type template-parameter, the non-type
9570 template-parameter is used in an expression in the function
9571 parameter-list and, if the corresponding template-argument is
9572 deduced, the template-argument type shall match the type of the
9573 template-parameter exactly, except that a template-argument
9574 deduced from an array bound may be of any integral type.
9575 The non-type parameter might use already deduced type parameters. */
9576 tparm = tsubst (TREE_TYPE (parm), targs, 0, NULL_TREE);
9577 if (!TREE_TYPE (arg))
9578 /* Template-parameter dependent expression. Just accept it for now.
9579 It will later be processed in convert_template_argument. */
9581 else if (same_type_p (TREE_TYPE (arg), tparm))
9583 else if ((strict & UNIFY_ALLOW_INTEGER)
9584 && (TREE_CODE (tparm) == INTEGER_TYPE
9585 || TREE_CODE (tparm) == BOOLEAN_TYPE))
9587 else if (uses_template_parms (tparm))
9588 /* We haven't deduced the type of this parameter yet. Try again
9594 TREE_VEC_ELT (targs, idx) = arg;
9599 if (TREE_CODE (arg) != POINTER_TYPE)
9602 /* [temp.deduct.call]
9604 A can be another pointer or pointer to member type that can
9605 be converted to the deduced A via a qualification
9606 conversion (_conv.qual_).
9608 We pass down STRICT here rather than UNIFY_ALLOW_NONE.
9609 This will allow for additional cv-qualification of the
9610 pointed-to types if appropriate. */
9612 if (TREE_CODE (TREE_TYPE (arg)) == RECORD_TYPE)
9613 /* The derived-to-base conversion only persists through one
9614 level of pointers. */
9615 strict |= (strict_in & UNIFY_ALLOW_DERIVED);
9617 return unify (tparms, targs, TREE_TYPE (parm),
9618 TREE_TYPE (arg), strict);
9621 case REFERENCE_TYPE:
9622 if (TREE_CODE (arg) != REFERENCE_TYPE)
9624 return unify (tparms, targs, TREE_TYPE (parm), TREE_TYPE (arg),
9625 strict & UNIFY_ALLOW_MORE_CV_QUAL);
9628 if (TREE_CODE (arg) != ARRAY_TYPE)
9630 if ((TYPE_DOMAIN (parm) == NULL_TREE)
9631 != (TYPE_DOMAIN (arg) == NULL_TREE))
9633 if (TYPE_DOMAIN (parm) != NULL_TREE
9634 && unify (tparms, targs, TYPE_DOMAIN (parm),
9635 TYPE_DOMAIN (arg), UNIFY_ALLOW_NONE) != 0)
9637 return unify (tparms, targs, TREE_TYPE (parm), TREE_TYPE (arg),
9638 strict & UNIFY_ALLOW_MORE_CV_QUAL);
9646 if (TREE_CODE (arg) != TREE_CODE (parm))
9649 if (TREE_CODE (parm) == INTEGER_TYPE
9650 && TREE_CODE (TYPE_MAX_VALUE (parm)) != INTEGER_CST)
9652 if (TYPE_MIN_VALUE (parm) && TYPE_MIN_VALUE (arg)
9653 && unify (tparms, targs, TYPE_MIN_VALUE (parm),
9654 TYPE_MIN_VALUE (arg), UNIFY_ALLOW_INTEGER))
9656 if (TYPE_MAX_VALUE (parm) && TYPE_MAX_VALUE (arg)
9657 && unify (tparms, targs, TYPE_MAX_VALUE (parm),
9658 TYPE_MAX_VALUE (arg),
9659 UNIFY_ALLOW_INTEGER | UNIFY_ALLOW_MAX_CORRECTION))
9662 /* We have already checked cv-qualification at the top of the
9664 else if (!same_type_ignoring_top_level_qualifiers_p (arg, parm))
9667 /* As far as unification is concerned, this wins. Later checks
9668 will invalidate it if necessary. */
9671 /* Types INTEGER_CST and MINUS_EXPR can come from array bounds. */
9672 /* Type INTEGER_CST can come from ordinary constant template args. */
9674 while (TREE_CODE (arg) == NOP_EXPR)
9675 arg = TREE_OPERAND (arg, 0);
9677 if (TREE_CODE (arg) != INTEGER_CST)
9679 return !tree_int_cst_equal (parm, arg);
9684 if (TREE_CODE (arg) != TREE_VEC)
9686 if (TREE_VEC_LENGTH (parm) != TREE_VEC_LENGTH (arg))
9688 for (i = 0; i < TREE_VEC_LENGTH (parm); ++i)
9689 if (unify (tparms, targs,
9690 TREE_VEC_ELT (parm, i), TREE_VEC_ELT (arg, i),
9698 if (TREE_CODE (arg) != TREE_CODE (parm))
9701 if (TYPE_PTRMEMFUNC_P (parm))
9703 if (!TYPE_PTRMEMFUNC_P (arg))
9706 return unify (tparms, targs,
9707 TYPE_PTRMEMFUNC_FN_TYPE (parm),
9708 TYPE_PTRMEMFUNC_FN_TYPE (arg),
9712 if (CLASSTYPE_TEMPLATE_INFO (parm))
9716 if (strict_in & UNIFY_ALLOW_DERIVED)
9718 /* First, we try to unify the PARM and ARG directly. */
9719 t = try_class_unification (tparms, targs,
9724 /* Fallback to the special case allowed in
9727 If P is a class, and P has the form
9728 template-id, then A can be a derived class of
9729 the deduced A. Likewise, if P is a pointer to
9730 a class of the form template-id, A can be a
9731 pointer to a derived class pointed to by the
9733 t = get_template_base (tparms, targs,
9736 if (! t || t == error_mark_node)
9740 else if (CLASSTYPE_TEMPLATE_INFO (arg)
9741 && (CLASSTYPE_TI_TEMPLATE (parm)
9742 == CLASSTYPE_TI_TEMPLATE (arg)))
9743 /* Perhaps PARM is something like S<U> and ARG is S<int>.
9744 Then, we should unify `int' and `U'. */
9747 /* There's no chance of unification succeeding. */
9750 return unify (tparms, targs, CLASSTYPE_TI_ARGS (parm),
9751 CLASSTYPE_TI_ARGS (t), UNIFY_ALLOW_NONE);
9753 else if (!same_type_ignoring_top_level_qualifiers_p (parm, arg))
9759 if (TREE_CODE (arg) != TREE_CODE (parm))
9762 if (unify (tparms, targs, TREE_TYPE (parm),
9763 TREE_TYPE (arg), UNIFY_ALLOW_NONE))
9765 return type_unification_real (tparms, targs, TYPE_ARG_TYPES (parm),
9766 TYPE_ARG_TYPES (arg), 1,
9767 DEDUCE_EXACT, 0, -1);
9770 if (TREE_CODE (arg) != OFFSET_TYPE)
9772 if (unify (tparms, targs, TYPE_OFFSET_BASETYPE (parm),
9773 TYPE_OFFSET_BASETYPE (arg), UNIFY_ALLOW_NONE))
9775 return unify (tparms, targs, TREE_TYPE (parm), TREE_TYPE (arg),
9779 if (DECL_TEMPLATE_PARM_P (parm))
9780 return unify (tparms, targs, DECL_INITIAL (parm), arg, strict);
9781 if (arg != decl_constant_value (parm))
9786 /* Matched cases are handled by the ARG == PARM test above. */
9790 if (tree_int_cst_equal (TREE_OPERAND (parm, 1), integer_one_node)
9791 && (strict_in & UNIFY_ALLOW_MAX_CORRECTION))
9793 /* We handle this case specially, since it comes up with
9794 arrays. In particular, something like:
9796 template <int N> void f(int (&x)[N]);
9798 Here, we are trying to unify the range type, which
9799 looks like [0 ... (N - 1)]. */
9801 t1 = TREE_OPERAND (parm, 0);
9802 t2 = TREE_OPERAND (parm, 1);
9804 t = fold (build (PLUS_EXPR, integer_type_node, arg, t2));
9806 return unify (tparms, targs, t1, t, strict);
9808 /* else fall through */
9811 if (IS_EXPR_CODE_CLASS (TREE_CODE_CLASS (TREE_CODE (parm))))
9814 /* We're looking at an expression. This can happen with
9818 void foo(S<I>, S<I + 2>);
9820 This is a "nondeduced context":
9824 The nondeduced contexts are:
9826 --A type that is a template-id in which one or more of
9827 the template-arguments is an expression that references
9828 a template-parameter.
9830 In these cases, we assume deduction succeeded, but don't
9831 actually infer any unifications. */
9833 if (!uses_template_parms (parm)
9834 && !template_args_equal (parm, arg))
9840 sorry ("use of `%s' in template type unification",
9841 tree_code_name [(int) TREE_CODE (parm)]);
9847 /* Called if RESULT is explicitly instantiated, or is a member of an
9848 explicitly instantiated class, or if using -frepo and the
9849 instantiation of RESULT has been assigned to this file. */
9852 mark_decl_instantiated (tree result, int extern_p)
9854 /* We used to set this unconditionally; we moved that to
9855 do_decl_instantiation so it wouldn't get set on members of
9856 explicit class template instantiations. But we still need to set
9857 it here for the 'extern template' case in order to suppress
9858 implicit instantiations. */
9860 SET_DECL_EXPLICIT_INSTANTIATION (result);
9862 /* If this entity has already been written out, it's too late to
9863 make any modifications. */
9864 if (TREE_ASM_WRITTEN (result))
9867 if (TREE_CODE (result) != FUNCTION_DECL)
9868 /* The TREE_PUBLIC flag for function declarations will have been
9869 set correctly by tsubst. */
9870 TREE_PUBLIC (result) = 1;
9872 /* This might have been set by an earlier implicit instantiation. */
9873 DECL_COMDAT (result) = 0;
9877 DECL_INTERFACE_KNOWN (result) = 1;
9878 DECL_NOT_REALLY_EXTERN (result) = 1;
9880 /* Always make artificials weak. */
9881 if (DECL_ARTIFICIAL (result) && flag_weak)
9882 comdat_linkage (result);
9883 /* For WIN32 we also want to put explicit instantiations in
9884 linkonce sections. */
9885 else if (TREE_PUBLIC (result))
9886 maybe_make_one_only (result);
9889 if (TREE_CODE (result) == FUNCTION_DECL)
9893 /* Given two function templates PAT1 and PAT2, return:
9895 DEDUCE should be DEDUCE_EXACT or DEDUCE_ORDER.
9897 1 if PAT1 is more specialized than PAT2 as described in [temp.func.order].
9898 -1 if PAT2 is more specialized than PAT1.
9899 0 if neither is more specialized.
9901 LEN is passed through to fn_type_unification. */
9904 more_specialized (tree pat1, tree pat2, int deduce, int len)
9909 /* If template argument deduction succeeds, we substitute the
9910 resulting arguments into non-deduced contexts. While doing that,
9911 we must be aware that we may encounter dependent types. */
9912 ++processing_template_decl;
9913 targs = get_bindings_real (pat1, DECL_TEMPLATE_RESULT (pat2),
9914 NULL_TREE, 0, deduce, len);
9918 targs = get_bindings_real (pat2, DECL_TEMPLATE_RESULT (pat1),
9919 NULL_TREE, 0, deduce, len);
9922 --processing_template_decl;
9927 /* Given two class template specialization list nodes PAT1 and PAT2, return:
9929 1 if PAT1 is more specialized than PAT2 as described in [temp.class.order].
9930 -1 if PAT2 is more specialized than PAT1.
9931 0 if neither is more specialized.
9933 FULL_ARGS is the full set of template arguments that triggers this
9934 partial ordering. */
9937 more_specialized_class (tree pat1, tree pat2, tree full_args)
9942 targs = get_class_bindings (TREE_VALUE (pat1), TREE_PURPOSE (pat1),
9943 add_outermost_template_args (full_args, TREE_PURPOSE (pat2)));
9947 targs = get_class_bindings (TREE_VALUE (pat2), TREE_PURPOSE (pat2),
9948 add_outermost_template_args (full_args, TREE_PURPOSE (pat1)));
9955 /* Return the template arguments that will produce the function signature
9956 DECL from the function template FN, with the explicit template
9957 arguments EXPLICIT_ARGS. If CHECK_RETTYPE is 1, the return type must
9958 also match. Return NULL_TREE if no satisfactory arguments could be
9959 found. DEDUCE and LEN are passed through to fn_type_unification. */
9962 get_bindings_real (tree fn,
9969 int ntparms = DECL_NTPARMS (fn);
9970 tree targs = make_tree_vec (ntparms);
9972 tree decl_arg_types;
9975 /* Substitute the explicit template arguments into the type of DECL.
9976 The call to fn_type_unification will handle substitution into the
9978 decl_type = TREE_TYPE (decl);
9979 if (explicit_args && uses_template_parms (decl_type))
9982 tree converted_args;
9984 if (DECL_TEMPLATE_INFO (decl))
9985 tmpl = DECL_TI_TEMPLATE (decl);
9987 /* We can get here for some invalid specializations. */
9991 = (coerce_template_parms (DECL_INNERMOST_TEMPLATE_PARMS (tmpl),
9992 explicit_args, NULL_TREE,
9993 tf_none, /*require_all_arguments=*/0));
9994 if (converted_args == error_mark_node)
9997 decl_type = tsubst (decl_type, converted_args, tf_none, NULL_TREE);
9998 if (decl_type == error_mark_node)
10002 decl_arg_types = TYPE_ARG_TYPES (decl_type);
10003 /* Never do unification on the 'this' parameter. */
10004 if (DECL_NONSTATIC_MEMBER_FUNCTION_P (decl))
10005 decl_arg_types = TREE_CHAIN (decl_arg_types);
10007 i = fn_type_unification (fn, explicit_args, targs,
10009 (check_rettype || DECL_CONV_FN_P (fn)
10010 ? TREE_TYPE (decl_type) : NULL_TREE),
10019 /* For most uses, we want to check the return type. */
10022 get_bindings (tree fn, tree decl, tree explicit_args)
10024 return get_bindings_real (fn, decl, explicit_args, 1, DEDUCE_EXACT, -1);
10027 /* But for resolve_overloaded_unification, we only care about the parameter
10031 get_bindings_overload (tree fn, tree decl, tree explicit_args)
10033 return get_bindings_real (fn, decl, explicit_args, 0, DEDUCE_EXACT, -1);
10036 /* Return the innermost template arguments that, when applied to a
10037 template specialization whose innermost template parameters are
10038 TPARMS, and whose specialization arguments are PARMS, yield the
10041 For example, suppose we have:
10043 template <class T, class U> struct S {};
10044 template <class T> struct S<T*, int> {};
10046 Then, suppose we want to get `S<double*, int>'. The TPARMS will be
10047 {T}, the PARMS will be {T*, int} and the ARGS will be {double*,
10048 int}. The resulting vector will be {double}, indicating that `T'
10049 is bound to `double'. */
10052 get_class_bindings (tree tparms, tree parms, tree args)
10054 int i, ntparms = TREE_VEC_LENGTH (tparms);
10055 tree vec = make_tree_vec (ntparms);
10057 if (unify (tparms, vec, parms, INNERMOST_TEMPLATE_ARGS (args),
10061 for (i = 0; i < ntparms; ++i)
10062 if (! TREE_VEC_ELT (vec, i))
10065 if (verify_class_unification (vec, parms, args))
10071 /* In INSTANTIATIONS is a list of <INSTANTIATION, TEMPLATE> pairs.
10072 Pick the most specialized template, and return the corresponding
10073 instantiation, or if there is no corresponding instantiation, the
10074 template itself. If there is no most specialized template,
10075 error_mark_node is returned. If there are no templates at all,
10076 NULL_TREE is returned. */
10079 most_specialized_instantiation (tree instantiations)
10084 if (!instantiations)
10087 champ = instantiations;
10088 for (fn = TREE_CHAIN (instantiations); fn; fn = TREE_CHAIN (fn))
10090 fate = more_specialized (TREE_VALUE (champ), TREE_VALUE (fn),
10098 fn = TREE_CHAIN (fn);
10100 return error_mark_node;
10106 for (fn = instantiations; fn && fn != champ; fn = TREE_CHAIN (fn))
10108 fate = more_specialized (TREE_VALUE (champ), TREE_VALUE (fn),
10111 return error_mark_node;
10114 return TREE_PURPOSE (champ) ? TREE_PURPOSE (champ) : TREE_VALUE (champ);
10117 /* Return the most specialized of the list of templates in FNS that can
10118 produce an instantiation matching DECL, given the explicit template
10119 arguments EXPLICIT_ARGS. */
10122 most_specialized (tree fns, tree decl, tree explicit_args)
10124 tree candidates = NULL_TREE;
10127 for (fn = fns; fn; fn = TREE_CHAIN (fn))
10129 tree candidate = TREE_VALUE (fn);
10131 args = get_bindings (candidate, decl, explicit_args);
10133 candidates = tree_cons (NULL_TREE, candidate, candidates);
10136 return most_specialized_instantiation (candidates);
10139 /* If DECL is a specialization of some template, return the most
10140 general such template. Otherwise, returns NULL_TREE.
10142 For example, given:
10144 template <class T> struct S { template <class U> void f(U); };
10146 if TMPL is `template <class U> void S<int>::f(U)' this will return
10147 the full template. This function will not trace past partial
10148 specializations, however. For example, given in addition:
10150 template <class T> struct S<T*> { template <class U> void f(U); };
10152 if TMPL is `template <class U> void S<int*>::f(U)' this will return
10153 `template <class T> template <class U> S<T*>::f(U)'. */
10156 most_general_template (tree decl)
10158 /* If DECL is a FUNCTION_DECL, find the TEMPLATE_DECL of which it is
10159 an immediate specialization. */
10160 if (TREE_CODE (decl) == FUNCTION_DECL)
10162 if (DECL_TEMPLATE_INFO (decl)) {
10163 decl = DECL_TI_TEMPLATE (decl);
10165 /* The DECL_TI_TEMPLATE can be an IDENTIFIER_NODE for a
10166 template friend. */
10167 if (TREE_CODE (decl) != TEMPLATE_DECL)
10173 /* Look for more and more general templates. */
10174 while (DECL_TEMPLATE_INFO (decl))
10176 /* The DECL_TI_TEMPLATE can be an IDENTIFIER_NODE in some cases.
10177 (See cp-tree.h for details.) */
10178 if (TREE_CODE (DECL_TI_TEMPLATE (decl)) != TEMPLATE_DECL)
10181 if (CLASS_TYPE_P (TREE_TYPE (decl))
10182 && CLASSTYPE_TEMPLATE_SPECIALIZATION (TREE_TYPE (decl)))
10185 /* Stop if we run into an explicitly specialized class template. */
10186 if (!DECL_NAMESPACE_SCOPE_P (decl)
10187 && DECL_CONTEXT (decl)
10188 && CLASSTYPE_TEMPLATE_SPECIALIZATION (DECL_CONTEXT (decl)))
10191 decl = DECL_TI_TEMPLATE (decl);
10197 /* Return the most specialized of the class template specializations
10198 of TMPL which can produce an instantiation matching ARGS, or
10199 error_mark_node if the choice is ambiguous. */
10202 most_specialized_class (tree tmpl, tree args)
10204 tree list = NULL_TREE;
10209 tmpl = most_general_template (tmpl);
10210 for (t = DECL_TEMPLATE_SPECIALIZATIONS (tmpl); t; t = TREE_CHAIN (t))
10213 = get_class_bindings (TREE_VALUE (t), TREE_PURPOSE (t), args);
10216 list = tree_cons (TREE_PURPOSE (t), TREE_VALUE (t), list);
10217 TREE_TYPE (list) = TREE_TYPE (t);
10226 t = TREE_CHAIN (t);
10227 for (; t; t = TREE_CHAIN (t))
10229 fate = more_specialized_class (champ, t, args);
10236 t = TREE_CHAIN (t);
10238 return error_mark_node;
10244 for (t = list; t && t != champ; t = TREE_CHAIN (t))
10246 fate = more_specialized_class (champ, t, args);
10248 return error_mark_node;
10254 /* Explicitly instantiate DECL. */
10257 do_decl_instantiation (tree decl, tree storage)
10259 tree result = NULL_TREE;
10263 /* An error occurred, for which grokdeclarator has already issued
10264 an appropriate message. */
10266 else if (! DECL_LANG_SPECIFIC (decl))
10268 error ("explicit instantiation of non-template `%#D'", decl);
10271 else if (TREE_CODE (decl) == VAR_DECL)
10273 /* There is an asymmetry here in the way VAR_DECLs and
10274 FUNCTION_DECLs are handled by grokdeclarator. In the case of
10275 the latter, the DECL we get back will be marked as a
10276 template instantiation, and the appropriate
10277 DECL_TEMPLATE_INFO will be set up. This does not happen for
10278 VAR_DECLs so we do the lookup here. Probably, grokdeclarator
10279 should handle VAR_DECLs as it currently handles
10281 result = lookup_field (DECL_CONTEXT (decl), DECL_NAME (decl), 0, false);
10282 if (!result || TREE_CODE (result) != VAR_DECL)
10284 error ("no matching template for `%D' found", decl);
10288 else if (TREE_CODE (decl) != FUNCTION_DECL)
10290 error ("explicit instantiation of `%#D'", decl);
10296 /* Check for various error cases. Note that if the explicit
10297 instantiation is valid the RESULT will currently be marked as an
10298 *implicit* instantiation; DECL_EXPLICIT_INSTANTIATION is not set
10299 until we get here. */
10301 if (DECL_TEMPLATE_SPECIALIZATION (result))
10303 /* DR 259 [temp.spec].
10305 Both an explicit instantiation and a declaration of an explicit
10306 specialization shall not appear in a program unless the explicit
10307 instantiation follows a declaration of the explicit specialization.
10309 For a given set of template parameters, if an explicit
10310 instantiation of a template appears after a declaration of an
10311 explicit specialization for that template, the explicit
10312 instantiation has no effect. */
10315 else if (DECL_EXPLICIT_INSTANTIATION (result))
10319 No program shall explicitly instantiate any template more
10322 We check DECL_INTERFACE_KNOWN so as not to complain when the first
10323 instantiation was `extern' and the second is not, and EXTERN_P for
10324 the opposite case. If -frepo, chances are we already got marked
10325 as an explicit instantiation because of the repo file. */
10326 if (DECL_INTERFACE_KNOWN (result) && !extern_p && !flag_use_repository)
10327 pedwarn ("duplicate explicit instantiation of `%#D'", result);
10329 /* If we've already instantiated the template, just return now. */
10330 if (DECL_INTERFACE_KNOWN (result))
10333 else if (!DECL_IMPLICIT_INSTANTIATION (result))
10335 error ("no matching template for `%D' found", result);
10338 else if (!DECL_TEMPLATE_INFO (result))
10340 pedwarn ("explicit instantiation of non-template `%#D'", result);
10344 if (flag_external_templates)
10347 if (storage == NULL_TREE)
10349 else if (storage == ridpointers[(int) RID_EXTERN])
10351 if (pedantic && !in_system_header)
10352 pedwarn ("ISO C++ forbids the use of `extern' on explicit instantiations");
10356 error ("storage class `%D' applied to template instantiation",
10359 SET_DECL_EXPLICIT_INSTANTIATION (result);
10360 mark_decl_instantiated (result, extern_p);
10361 repo_template_instantiated (result, extern_p);
10363 instantiate_decl (result, /*defer_ok=*/1);
10367 mark_class_instantiated (tree t, int extern_p)
10369 SET_CLASSTYPE_EXPLICIT_INSTANTIATION (t);
10370 SET_CLASSTYPE_INTERFACE_KNOWN (t);
10371 CLASSTYPE_INTERFACE_ONLY (t) = extern_p;
10372 TYPE_DECL_SUPPRESS_DEBUG (TYPE_NAME (t)) = extern_p;
10375 CLASSTYPE_DEBUG_REQUESTED (t) = 1;
10376 rest_of_type_compilation (t, 1);
10380 /* Called from do_type_instantiation through binding_table_foreach to
10381 do recursive instantiation for the type bound in ENTRY. */
10383 bt_instantiate_type_proc (binding_entry entry, void *data)
10385 tree storage = *(tree *) data;
10387 if (IS_AGGR_TYPE (entry->type)
10388 && !uses_template_parms (CLASSTYPE_TI_ARGS (entry->type)))
10389 do_type_instantiation (TYPE_MAIN_DECL (entry->type), storage, 0);
10392 /* Perform an explicit instantiation of template class T. STORAGE, if
10393 non-null, is the RID for extern, inline or static. COMPLAIN is
10394 nonzero if this is called from the parser, zero if called recursively,
10395 since the standard is unclear (as detailed below). */
10398 do_type_instantiation (tree t, tree storage, tsubst_flags_t complain)
10404 if (TREE_CODE (t) == TYPE_DECL)
10407 if (! CLASS_TYPE_P (t) || ! CLASSTYPE_TEMPLATE_INFO (t))
10409 error ("explicit instantiation of non-template type `%T'", t);
10415 /* With -fexternal-templates, explicit instantiations are treated the same
10416 as implicit ones. */
10417 if (flag_external_templates)
10420 if (!COMPLETE_TYPE_P (t))
10422 if (complain & tf_error)
10423 error ("explicit instantiation of `%#T' before definition of template",
10428 if (storage != NULL_TREE)
10430 if (pedantic && !in_system_header)
10431 pedwarn("ISO C++ forbids the use of `%s' on explicit instantiations",
10432 IDENTIFIER_POINTER (storage));
10434 if (storage == ridpointers[(int) RID_INLINE])
10436 else if (storage == ridpointers[(int) RID_EXTERN])
10438 else if (storage == ridpointers[(int) RID_STATIC])
10442 error ("storage class `%D' applied to template instantiation",
10448 if (CLASSTYPE_TEMPLATE_SPECIALIZATION (t))
10450 /* DR 259 [temp.spec].
10452 Both an explicit instantiation and a declaration of an explicit
10453 specialization shall not appear in a program unless the explicit
10454 instantiation follows a declaration of the explicit specialization.
10456 For a given set of template parameters, if an explicit
10457 instantiation of a template appears after a declaration of an
10458 explicit specialization for that template, the explicit
10459 instantiation has no effect. */
10462 else if (CLASSTYPE_EXPLICIT_INSTANTIATION (t))
10466 No program shall explicitly instantiate any template more
10469 If CLASSTYPE_INTERFACE_ONLY, then the first explicit instantiation
10470 was `extern'. If EXTERN_P then the second is. If -frepo, chances
10471 are we already got marked as an explicit instantiation because of the
10472 repo file. All these cases are OK. */
10473 if (!CLASSTYPE_INTERFACE_ONLY (t) && !extern_p && !flag_use_repository
10474 && (complain & tf_error))
10475 pedwarn ("duplicate explicit instantiation of `%#T'", t);
10477 /* If we've already instantiated the template, just return now. */
10478 if (!CLASSTYPE_INTERFACE_ONLY (t))
10482 mark_class_instantiated (t, extern_p);
10483 repo_template_instantiated (t, extern_p);
10491 /* In contrast to implicit instantiation, where only the
10492 declarations, and not the definitions, of members are
10493 instantiated, we have here:
10497 The explicit instantiation of a class template specialization
10498 implies the instantiation of all of its members not
10499 previously explicitly specialized in the translation unit
10500 containing the explicit instantiation.
10502 Of course, we can't instantiate member template classes, since
10503 we don't have any arguments for them. Note that the standard
10504 is unclear on whether the instantiation of the members are
10505 *explicit* instantiations or not. We choose to be generous,
10506 and not set DECL_EXPLICIT_INSTANTIATION. Therefore, we allow
10507 the explicit instantiation of a class where some of the members
10508 have no definition in the current translation unit. */
10511 for (tmp = TYPE_METHODS (t); tmp; tmp = TREE_CHAIN (tmp))
10512 if (TREE_CODE (tmp) == FUNCTION_DECL
10513 && DECL_TEMPLATE_INSTANTIATION (tmp))
10515 mark_decl_instantiated (tmp, extern_p);
10516 repo_template_instantiated (tmp, extern_p);
10518 instantiate_decl (tmp, /*defer_ok=*/1);
10521 for (tmp = TYPE_FIELDS (t); tmp; tmp = TREE_CHAIN (tmp))
10522 if (TREE_CODE (tmp) == VAR_DECL && DECL_TEMPLATE_INSTANTIATION (tmp))
10524 mark_decl_instantiated (tmp, extern_p);
10525 repo_template_instantiated (tmp, extern_p);
10527 instantiate_decl (tmp, /*defer_ok=*/1);
10530 if (CLASSTYPE_NESTED_UTDS (t))
10531 binding_table_foreach (CLASSTYPE_NESTED_UTDS (t),
10532 bt_instantiate_type_proc, &storage);
10536 /* Given a function DECL, which is a specialization of TMPL, modify
10537 DECL to be a re-instantiation of TMPL with the same template
10538 arguments. TMPL should be the template into which tsubst'ing
10539 should occur for DECL, not the most general template.
10541 One reason for doing this is a scenario like this:
10544 void f(const T&, int i);
10546 void g() { f(3, 7); }
10549 void f(const T& t, const int i) { }
10551 Note that when the template is first instantiated, with
10552 instantiate_template, the resulting DECL will have no name for the
10553 first parameter, and the wrong type for the second. So, when we go
10554 to instantiate the DECL, we regenerate it. */
10557 regenerate_decl_from_template (tree decl, tree tmpl)
10559 /* The most general version of TMPL. */
10561 /* The arguments used to instantiate DECL, from the most general
10568 args = DECL_TI_ARGS (decl);
10569 code_pattern = DECL_TEMPLATE_RESULT (tmpl);
10571 /* Unregister the specialization so that when we tsubst we will not
10572 just return DECL. We don't have to unregister DECL from TMPL
10573 because if would only be registered there if it were a partial
10574 instantiation of a specialization, which it isn't: it's a full
10576 gen_tmpl = most_general_template (tmpl);
10577 unregistered = reregister_specialization (decl, gen_tmpl,
10578 /*new_spec=*/NULL_TREE);
10580 /* If the DECL was not unregistered then something peculiar is
10581 happening: we created a specialization but did not call
10582 register_specialization for it. */
10583 my_friendly_assert (unregistered, 0);
10585 /* Make sure that we can see identifiers, and compute access
10587 push_access_scope (decl);
10589 /* Do the substitution to get the new declaration. */
10590 new_decl = tsubst (code_pattern, args, tf_error, NULL_TREE);
10592 if (TREE_CODE (decl) == VAR_DECL)
10594 /* Set up DECL_INITIAL, since tsubst doesn't. */
10595 if (!DECL_INITIALIZED_IN_CLASS_P (decl))
10596 DECL_INITIAL (new_decl) =
10597 tsubst_expr (DECL_INITIAL (code_pattern), args,
10598 tf_error, DECL_TI_TEMPLATE (decl));
10600 else if (TREE_CODE (decl) == FUNCTION_DECL)
10602 /* Convince duplicate_decls to use the DECL_ARGUMENTS from the
10604 DECL_INITIAL (new_decl) = error_mark_node;
10605 /* And don't complain about a duplicate definition. */
10606 DECL_INITIAL (decl) = NULL_TREE;
10609 pop_access_scope (decl);
10611 /* The immediate parent of the new template is still whatever it was
10612 before, even though tsubst sets DECL_TI_TEMPLATE up as the most
10613 general template. We also reset the DECL_ASSEMBLER_NAME since
10614 tsubst always calculates the name as if the function in question
10615 were really a template instance, and sometimes, with friend
10616 functions, this is not so. See tsubst_friend_function for
10618 DECL_TI_TEMPLATE (new_decl) = DECL_TI_TEMPLATE (decl);
10619 COPY_DECL_ASSEMBLER_NAME (decl, new_decl);
10620 COPY_DECL_RTL (decl, new_decl);
10621 DECL_USE_TEMPLATE (new_decl) = DECL_USE_TEMPLATE (decl);
10623 /* Call duplicate decls to merge the old and new declarations. */
10624 duplicate_decls (new_decl, decl);
10626 /* Now, re-register the specialization. */
10627 register_specialization (decl, gen_tmpl, args);
10630 /* Return the TEMPLATE_DECL into which DECL_TI_ARGS(DECL) should be
10631 substituted to get DECL. */
10634 template_for_substitution (tree decl)
10636 tree tmpl = DECL_TI_TEMPLATE (decl);
10638 /* Set TMPL to the template whose DECL_TEMPLATE_RESULT is the pattern
10639 for the instantiation. This is not always the most general
10640 template. Consider, for example:
10643 struct S { template <class U> void f();
10644 template <> void f<int>(); };
10646 and an instantiation of S<double>::f<int>. We want TD to be the
10647 specialization S<T>::f<int>, not the more general S<T>::f<U>. */
10648 while (/* An instantiation cannot have a definition, so we need a
10649 more general template. */
10650 DECL_TEMPLATE_INSTANTIATION (tmpl)
10651 /* We must also deal with friend templates. Given:
10653 template <class T> struct S {
10654 template <class U> friend void f() {};
10657 S<int>::f<U> say, is not an instantiation of S<T>::f<U>,
10658 so far as the language is concerned, but that's still
10659 where we get the pattern for the instantiation from. On
10660 other hand, if the definition comes outside the class, say:
10662 template <class T> struct S {
10663 template <class U> friend void f();
10665 template <class U> friend void f() {}
10667 we don't need to look any further. That's what the check for
10668 DECL_INITIAL is for. */
10669 || (TREE_CODE (decl) == FUNCTION_DECL
10670 && DECL_FRIEND_PSEUDO_TEMPLATE_INSTANTIATION (tmpl)
10671 && !DECL_INITIAL (DECL_TEMPLATE_RESULT (tmpl))))
10673 /* The present template, TD, should not be a definition. If it
10674 were a definition, we should be using it! Note that we
10675 cannot restructure the loop to just keep going until we find
10676 a template with a definition, since that might go too far if
10677 a specialization was declared, but not defined. */
10678 my_friendly_assert (!(TREE_CODE (decl) == VAR_DECL
10679 && !DECL_IN_AGGR_P (DECL_TEMPLATE_RESULT (tmpl))),
10682 /* Fetch the more general template. */
10683 tmpl = DECL_TI_TEMPLATE (tmpl);
10689 /* Produce the definition of D, a _DECL generated from a template. If
10690 DEFER_OK is nonzero, then we don't have to actually do the
10691 instantiation now; we just have to do it sometime. */
10694 instantiate_decl (tree d, int defer_ok)
10696 tree tmpl = DECL_TI_TEMPLATE (d);
10703 int pattern_defined;
10705 location_t saved_loc = input_location;
10707 /* This function should only be used to instantiate templates for
10708 functions and static member variables. */
10709 my_friendly_assert (TREE_CODE (d) == FUNCTION_DECL
10710 || TREE_CODE (d) == VAR_DECL, 0);
10712 /* Variables are never deferred; if instantiation is required, they
10713 are instantiated right away. That allows for better code in the
10714 case that an expression refers to the value of the variable --
10715 if the variable has a constant value the referring expression can
10716 take advantage of that fact. */
10717 if (TREE_CODE (d) == VAR_DECL)
10720 /* Don't instantiate cloned functions. Instead, instantiate the
10721 functions they cloned. */
10722 if (TREE_CODE (d) == FUNCTION_DECL && DECL_CLONED_FUNCTION_P (d))
10723 d = DECL_CLONED_FUNCTION (d);
10725 if (DECL_TEMPLATE_INSTANTIATED (d))
10726 /* D has already been instantiated. It might seem reasonable to
10727 check whether or not D is an explicit instantiation, and, if so,
10728 stop here. But when an explicit instantiation is deferred
10729 until the end of the compilation, DECL_EXPLICIT_INSTANTIATION
10730 is set, even though we still need to do the instantiation. */
10733 /* If we already have a specialization of this declaration, then
10734 there's no reason to instantiate it. Note that
10735 retrieve_specialization gives us both instantiations and
10736 specializations, so we must explicitly check
10737 DECL_TEMPLATE_SPECIALIZATION. */
10738 gen_tmpl = most_general_template (tmpl);
10739 gen_args = DECL_TI_ARGS (d);
10740 spec = retrieve_specialization (gen_tmpl, gen_args);
10741 if (spec != NULL_TREE && DECL_TEMPLATE_SPECIALIZATION (spec))
10744 /* This needs to happen before any tsubsting. */
10745 if (! push_tinst_level (d))
10748 timevar_push (TV_PARSE);
10750 /* We may be in the middle of deferred access check. Disable it now. */
10751 push_deferring_access_checks (dk_no_deferred);
10753 /* Our caller does not expect collection to happen, which it might if
10754 we decide to compile the function to rtl now. Arrange for a new
10755 gc context to be created if so. */
10758 /* Set TD to the template whose DECL_TEMPLATE_RESULT is the pattern
10759 for the instantiation. */
10760 td = template_for_substitution (d);
10761 code_pattern = DECL_TEMPLATE_RESULT (td);
10763 if ((DECL_NAMESPACE_SCOPE_P (d) && !DECL_INITIALIZED_IN_CLASS_P (d))
10764 || DECL_TEMPLATE_SPECIALIZATION (td))
10765 /* In the case of a friend template whose definition is provided
10766 outside the class, we may have too many arguments. Drop the
10767 ones we don't need. The same is true for specializations. */
10768 args = get_innermost_template_args
10769 (gen_args, TMPL_PARMS_DEPTH (DECL_TEMPLATE_PARMS (td)));
10773 if (TREE_CODE (d) == FUNCTION_DECL)
10774 pattern_defined = (DECL_SAVED_TREE (code_pattern) != NULL_TREE);
10776 pattern_defined = ! DECL_IN_AGGR_P (code_pattern);
10778 input_location = DECL_SOURCE_LOCATION (d);
10780 if (pattern_defined)
10782 /* Let the repository code that this template definition is
10785 The repository doesn't need to know about cloned functions
10786 because they never actually show up in the object file. It
10787 does need to know about the clones; those are the symbols
10788 that the linker will be emitting error messages about. */
10789 if (DECL_MAYBE_IN_CHARGE_CONSTRUCTOR_P (d)
10790 || DECL_MAYBE_IN_CHARGE_DESTRUCTOR_P (d))
10794 for (t = TREE_CHAIN (d);
10795 t && DECL_CLONED_FUNCTION_P (t);
10796 t = TREE_CHAIN (t))
10797 repo_template_used (t);
10800 repo_template_used (d);
10802 if (flag_external_templates && ! DECL_INTERFACE_KNOWN (d))
10804 if (flag_alt_external_templates)
10806 if (interface_unknown)
10807 warn_if_unknown_interface (d);
10809 else if (DECL_INTERFACE_KNOWN (code_pattern))
10811 DECL_INTERFACE_KNOWN (d) = 1;
10812 DECL_NOT_REALLY_EXTERN (d) = ! DECL_EXTERNAL (code_pattern);
10815 warn_if_unknown_interface (code_pattern);
10819 import_export_decl (d);
10824 /* Recheck the substitutions to obtain any warning messages
10825 about ignoring cv qualifiers. */
10826 tree gen = DECL_TEMPLATE_RESULT (gen_tmpl);
10827 tree type = TREE_TYPE (gen);
10829 /* Make sure that we can see identifiers, and compute access
10830 correctly. D is already the target FUNCTION_DECL with the
10832 push_access_scope (d);
10834 if (TREE_CODE (gen) == FUNCTION_DECL)
10836 tsubst (DECL_ARGUMENTS (gen), gen_args, tf_error | tf_warning, d);
10837 tsubst (TYPE_RAISES_EXCEPTIONS (type), gen_args,
10838 tf_error | tf_warning, d);
10839 /* Don't simply tsubst the function type, as that will give
10840 duplicate warnings about poor parameter qualifications.
10841 The function arguments are the same as the decl_arguments
10842 without the top level cv qualifiers. */
10843 type = TREE_TYPE (type);
10845 tsubst (type, gen_args, tf_error | tf_warning, d);
10847 pop_access_scope (d);
10850 if (TREE_CODE (d) == VAR_DECL && DECL_INITIALIZED_IN_CLASS_P (d)
10851 && DECL_INITIAL (d) == NULL_TREE)
10852 /* We should have set up DECL_INITIAL in instantiate_class_template. */
10854 /* Reject all external templates except inline functions. */
10855 else if (DECL_INTERFACE_KNOWN (d)
10856 && ! DECL_NOT_REALLY_EXTERN (d)
10857 && ! (TREE_CODE (d) == FUNCTION_DECL
10858 && DECL_INLINE (d)))
10860 /* Defer all other templates, unless we have been explicitly
10861 forbidden from doing so. We restore the source position here
10862 because it's used by add_pending_template. */
10863 else if (! pattern_defined || defer_ok)
10865 input_location = saved_loc;
10867 if (at_eof && !pattern_defined
10868 && DECL_EXPLICIT_INSTANTIATION (d))
10871 The definition of a non-exported function template, a
10872 non-exported member function template, or a non-exported
10873 member function or static data member of a class template
10874 shall be present in every translation unit in which it is
10875 explicitly instantiated. */
10877 ("explicit instantiation of `%D' but no definition available", d);
10879 add_pending_template (d);
10883 need_push = !global_bindings_p ();
10885 push_to_top_level ();
10887 /* Regenerate the declaration in case the template has been modified
10888 by a subsequent redeclaration. */
10889 regenerate_decl_from_template (d, td);
10891 /* We already set the file and line above. Reset them now in case
10892 they changed as a result of calling
10893 regenerate_decl_from_template. */
10894 input_location = DECL_SOURCE_LOCATION (d);
10896 if (TREE_CODE (d) == VAR_DECL)
10898 /* Clear out DECL_RTL; whatever was there before may not be right
10899 since we've reset the type of the declaration. */
10900 SET_DECL_RTL (d, NULL_RTX);
10902 DECL_IN_AGGR_P (d) = 0;
10903 import_export_decl (d);
10904 DECL_EXTERNAL (d) = ! DECL_NOT_REALLY_EXTERN (d);
10906 if (DECL_EXTERNAL (d))
10908 /* The fact that this code is executing indicates that:
10910 (1) D is a template static data member, for which a
10911 definition is available.
10913 (2) An implicit or explicit instantiation has occurred.
10915 (3) We are not going to emit a definition of the static
10916 data member at this time.
10918 This situation is peculiar, but it occurs on platforms
10919 without weak symbols when performing an implicit
10920 instantiation. There, we cannot implicitly instantiate a
10921 defined static data member in more than one translation
10922 unit, so import_export_decl marks the declaration as
10923 external; we must rely on explicit instantiation. */
10927 /* Mark D as instantiated so that recursive calls to
10928 instantiate_decl do not try to instantiate it again. */
10929 DECL_TEMPLATE_INSTANTIATED (d) = 1;
10931 (!DECL_INITIALIZED_IN_CLASS_P (d)
10932 ? DECL_INITIAL (d) : NULL_TREE),
10936 else if (TREE_CODE (d) == FUNCTION_DECL)
10938 htab_t saved_local_specializations;
10943 /* Mark D as instantiated so that recursive calls to
10944 instantiate_decl do not try to instantiate it again. */
10945 DECL_TEMPLATE_INSTANTIATED (d) = 1;
10947 /* Save away the current list, in case we are instantiating one
10948 template from within the body of another. */
10949 saved_local_specializations = local_specializations;
10951 /* Set up the list of local specializations. */
10952 local_specializations = htab_create (37,
10953 hash_local_specialization,
10954 eq_local_specializations,
10957 /* Set up context. */
10958 import_export_decl (d);
10959 start_function (NULL_TREE, d, NULL_TREE, SF_PRE_PARSED);
10961 /* Create substitution entries for the parameters. */
10962 subst_decl = DECL_TEMPLATE_RESULT (template_for_substitution (d));
10963 tmpl_parm = DECL_ARGUMENTS (subst_decl);
10964 spec_parm = DECL_ARGUMENTS (d);
10965 if (DECL_NONSTATIC_MEMBER_FUNCTION_P (d))
10967 register_local_specialization (spec_parm, tmpl_parm);
10968 spec_parm = skip_artificial_parms_for (d, spec_parm);
10969 tmpl_parm = skip_artificial_parms_for (subst_decl, tmpl_parm);
10973 register_local_specialization (spec_parm, tmpl_parm);
10974 tmpl_parm = TREE_CHAIN (tmpl_parm);
10975 spec_parm = TREE_CHAIN (spec_parm);
10977 my_friendly_assert (!spec_parm, 20020813);
10979 /* Substitute into the body of the function. */
10980 tsubst_expr (DECL_SAVED_TREE (code_pattern), args,
10981 tf_error | tf_warning, tmpl);
10983 /* We don't need the local specializations any more. */
10984 htab_delete (local_specializations);
10985 local_specializations = saved_local_specializations;
10987 /* Finish the function. */
10988 d = finish_function (0);
10989 expand_or_defer_fn (d);
10992 /* We're not deferring instantiation any more. */
10993 TI_PENDING_TEMPLATE_FLAG (DECL_TEMPLATE_INFO (d)) = 0;
10996 pop_from_top_level ();
10999 input_location = saved_loc;
11000 pop_deferring_access_checks ();
11001 pop_tinst_level ();
11004 timevar_pop (TV_PARSE);
11009 /* Run through the list of templates that we wish we could
11010 instantiate, and instantiate any we can. */
11013 instantiate_pending_templates (void)
11016 tree last = NULL_TREE;
11017 int instantiated_something = 0;
11024 t = &pending_templates;
11027 tree instantiation = TREE_VALUE (*t);
11029 reopen_tinst_level (TREE_PURPOSE (*t));
11031 if (TYPE_P (instantiation))
11035 if (!COMPLETE_TYPE_P (instantiation))
11037 instantiate_class_template (instantiation);
11038 if (CLASSTYPE_TEMPLATE_INSTANTIATION (instantiation))
11039 for (fn = TYPE_METHODS (instantiation);
11041 fn = TREE_CHAIN (fn))
11042 if (! DECL_ARTIFICIAL (fn))
11043 instantiate_decl (fn, /*defer_ok=*/0);
11044 if (COMPLETE_TYPE_P (instantiation))
11046 instantiated_something = 1;
11051 if (COMPLETE_TYPE_P (instantiation))
11052 /* If INSTANTIATION has been instantiated, then we don't
11053 need to consider it again in the future. */
11054 *t = TREE_CHAIN (*t);
11058 t = &TREE_CHAIN (*t);
11063 if (!DECL_TEMPLATE_SPECIALIZATION (instantiation)
11064 && !DECL_TEMPLATE_INSTANTIATED (instantiation))
11066 instantiation = instantiate_decl (instantiation,
11068 if (DECL_TEMPLATE_INSTANTIATED (instantiation))
11070 instantiated_something = 1;
11075 if (DECL_TEMPLATE_SPECIALIZATION (instantiation)
11076 || DECL_TEMPLATE_INSTANTIATED (instantiation))
11077 /* If INSTANTIATION has been instantiated, then we don't
11078 need to consider it again in the future. */
11079 *t = TREE_CHAIN (*t);
11083 t = &TREE_CHAIN (*t);
11087 current_tinst_level = NULL_TREE;
11089 last_pending_template = last;
11091 while (reconsider);
11093 return instantiated_something;
11096 /* Substitute ARGVEC into T, which is a list of initializers for
11097 either base class or a non-static data member. The TREE_PURPOSEs
11098 are DECLs, and the TREE_VALUEs are the initializer values. Used by
11099 instantiate_decl. */
11102 tsubst_initializer_list (tree t, tree argvec)
11104 tree inits = NULL_TREE;
11106 for (; t; t = TREE_CHAIN (t))
11112 decl = tsubst_copy (TREE_PURPOSE (t), argvec, tf_error | tf_warning,
11114 decl = expand_member_init (decl);
11115 if (decl && !DECL_P (decl))
11116 in_base_initializer = 1;
11118 init = tsubst_expr (TREE_VALUE (t), argvec, tf_error | tf_warning,
11122 else if (TREE_CODE (init) == TREE_LIST)
11123 for (val = init; val; val = TREE_CHAIN (val))
11124 TREE_VALUE (val) = convert_from_reference (TREE_VALUE (val));
11125 else if (init != void_type_node)
11126 init = convert_from_reference (init);
11128 in_base_initializer = 0;
11132 init = build_tree_list (decl, init);
11133 TREE_CHAIN (init) = inits;
11140 /* Set CURRENT_ACCESS_SPECIFIER based on the protection of DECL. */
11143 set_current_access_from_decl (tree decl)
11145 if (TREE_PRIVATE (decl))
11146 current_access_specifier = access_private_node;
11147 else if (TREE_PROTECTED (decl))
11148 current_access_specifier = access_protected_node;
11150 current_access_specifier = access_public_node;
11153 /* Instantiate an enumerated type. TAG is the template type, NEWTAG
11154 is the instantiation (which should have been created with
11155 start_enum) and ARGS are the template arguments to use. */
11158 tsubst_enum (tree tag, tree newtag, tree args)
11162 for (e = TYPE_VALUES (tag); e; e = TREE_CHAIN (e))
11167 decl = TREE_VALUE (e);
11168 /* Note that in a template enum, the TREE_VALUE is the
11169 CONST_DECL, not the corresponding INTEGER_CST. */
11170 value = tsubst_expr (DECL_INITIAL (decl),
11171 args, tf_error | tf_warning,
11174 /* Give this enumeration constant the correct access. */
11175 set_current_access_from_decl (decl);
11177 /* Actually build the enumerator itself. */
11178 build_enumerator (DECL_NAME (decl), value, newtag);
11181 finish_enum (newtag);
11182 DECL_SOURCE_LOCATION (TYPE_NAME (newtag))
11183 = DECL_SOURCE_LOCATION (TYPE_NAME (tag));
11186 /* DECL is a FUNCTION_DECL that is a template specialization. Return
11187 its type -- but without substituting the innermost set of template
11188 arguments. So, innermost set of template parameters will appear in
11192 get_mostly_instantiated_function_type (tree decl)
11200 tmpl = most_general_template (DECL_TI_TEMPLATE (decl));
11201 targs = DECL_TI_ARGS (decl);
11202 tparms = DECL_TEMPLATE_PARMS (tmpl);
11203 parm_depth = TMPL_PARMS_DEPTH (tparms);
11205 /* There should be as many levels of arguments as there are levels
11207 my_friendly_assert (parm_depth == TMPL_ARGS_DEPTH (targs), 0);
11209 fn_type = TREE_TYPE (tmpl);
11211 if (parm_depth == 1)
11212 /* No substitution is necessary. */
11219 /* Replace the innermost level of the TARGS with NULL_TREEs to
11220 let tsubst know not to substitute for those parameters. */
11221 partial_args = make_tree_vec (TREE_VEC_LENGTH (targs));
11222 for (i = 1; i < TMPL_ARGS_DEPTH (targs); ++i)
11223 SET_TMPL_ARGS_LEVEL (partial_args, i,
11224 TMPL_ARGS_LEVEL (targs, i));
11225 SET_TMPL_ARGS_LEVEL (partial_args,
11226 TMPL_ARGS_DEPTH (targs),
11227 make_tree_vec (DECL_NTPARMS (tmpl)));
11229 /* Make sure that we can see identifiers, and compute access
11230 correctly. We can just use the context of DECL for the
11231 partial substitution here. It depends only on outer template
11232 parameters, regardless of whether the innermost level is
11233 specialized or not. */
11234 push_access_scope (decl);
11236 /* Now, do the (partial) substitution to figure out the
11237 appropriate function type. */
11238 fn_type = tsubst (fn_type, partial_args, tf_error, NULL_TREE);
11240 /* Substitute into the template parameters to obtain the real
11241 innermost set of parameters. This step is important if the
11242 innermost set of template parameters contains value
11243 parameters whose types depend on outer template parameters. */
11244 TREE_VEC_LENGTH (partial_args)--;
11245 tparms = tsubst_template_parms (tparms, partial_args, tf_error);
11247 pop_access_scope (decl);
11253 /* Return truthvalue if we're processing a template different from
11254 the last one involved in diagnostics. */
11256 problematic_instantiation_changed (void)
11258 return last_template_error_tick != tinst_level_tick;
11261 /* Remember current template involved in diagnostics. */
11263 record_last_problematic_instantiation (void)
11265 last_template_error_tick = tinst_level_tick;
11269 current_instantiation (void)
11271 return current_tinst_level;
11274 /* [temp.param] Check that template non-type parm TYPE is of an allowable
11275 type. Return zero for ok, nonzero for disallowed. Issue error and
11276 warning messages under control of COMPLAIN. */
11279 invalid_nontype_parm_type_p (tree type, tsubst_flags_t complain)
11281 if (INTEGRAL_TYPE_P (type))
11283 else if (POINTER_TYPE_P (type))
11285 else if (TYPE_PTR_TO_MEMBER_P (type))
11287 else if (TREE_CODE (type) == TEMPLATE_TYPE_PARM)
11289 else if (TREE_CODE (type) == TYPENAME_TYPE)
11292 if (complain & tf_error)
11293 error ("`%#T' is not a valid type for a template constant parameter",
11298 /* Returns TRUE if TYPE is dependent, in the sense of [temp.dep.type].
11299 Assumes that TYPE really is a type, and not the ERROR_MARK_NODE.*/
11302 dependent_type_p_r (tree type)
11308 A type is dependent if it is:
11310 -- a template parameter. */
11311 if (TREE_CODE (type) == TEMPLATE_TYPE_PARM)
11313 /* -- a qualified-id with a nested-name-specifier which contains a
11314 class-name that names a dependent type or whose unqualified-id
11315 names a dependent type. */
11316 if (TREE_CODE (type) == TYPENAME_TYPE)
11318 /* -- a cv-qualified type where the cv-unqualified type is
11320 type = TYPE_MAIN_VARIANT (type);
11321 /* -- a compound type constructed from any dependent type. */
11322 if (TYPE_PTR_TO_MEMBER_P (type))
11323 return (dependent_type_p (TYPE_PTRMEM_CLASS_TYPE (type))
11324 || dependent_type_p (TYPE_PTRMEM_POINTED_TO_TYPE
11326 else if (TREE_CODE (type) == POINTER_TYPE
11327 || TREE_CODE (type) == REFERENCE_TYPE)
11328 return dependent_type_p (TREE_TYPE (type));
11329 else if (TREE_CODE (type) == FUNCTION_TYPE
11330 || TREE_CODE (type) == METHOD_TYPE)
11334 if (dependent_type_p (TREE_TYPE (type)))
11336 for (arg_type = TYPE_ARG_TYPES (type);
11338 arg_type = TREE_CHAIN (arg_type))
11339 if (dependent_type_p (TREE_VALUE (arg_type)))
11343 /* -- an array type constructed from any dependent type or whose
11344 size is specified by a constant expression that is
11345 value-dependent. */
11346 if (TREE_CODE (type) == ARRAY_TYPE)
11348 if (TYPE_DOMAIN (type)
11349 && ((value_dependent_expression_p
11350 (TYPE_MAX_VALUE (TYPE_DOMAIN (type))))
11351 || (type_dependent_expression_p
11352 (TYPE_MAX_VALUE (TYPE_DOMAIN (type))))))
11354 return dependent_type_p (TREE_TYPE (type));
11357 /* -- a template-id in which either the template name is a template
11359 if (TREE_CODE (type) == BOUND_TEMPLATE_TEMPLATE_PARM)
11361 /* ... or any of the template arguments is a dependent type or
11362 an expression that is type-dependent or value-dependent. */
11363 else if (CLASS_TYPE_P (type) && CLASSTYPE_TEMPLATE_INFO (type)
11364 && (any_dependent_template_arguments_p
11365 (INNERMOST_TEMPLATE_ARGS (CLASSTYPE_TI_ARGS (type)))))
11368 /* All TYPEOF_TYPEs are dependent; if the argument of the `typeof'
11369 expression is not type-dependent, then it should already been
11371 if (TREE_CODE (type) == TYPEOF_TYPE)
11374 /* The standard does not specifically mention types that are local
11375 to template functions or local classes, but they should be
11376 considered dependent too. For example:
11378 template <int I> void f() {
11383 The size of `E' cannot be known until the value of `I' has been
11384 determined. Therefore, `E' must be considered dependent. */
11385 scope = TYPE_CONTEXT (type);
11386 if (scope && TYPE_P (scope))
11387 return dependent_type_p (scope);
11388 else if (scope && TREE_CODE (scope) == FUNCTION_DECL)
11389 return type_dependent_expression_p (scope);
11391 /* Other types are non-dependent. */
11395 /* Returns TRUE if TYPE is dependent, in the sense of
11396 [temp.dep.type]. */
11399 dependent_type_p (tree type)
11401 /* If there are no template parameters in scope, then there can't be
11402 any dependent types. */
11403 if (!processing_template_decl)
11406 /* If the type is NULL, we have not computed a type for the entity
11407 in question; in that case, the type is dependent. */
11411 /* Erroneous types can be considered non-dependent. */
11412 if (type == error_mark_node)
11415 /* If we have not already computed the appropriate value for TYPE,
11417 if (!TYPE_DEPENDENT_P_VALID (type))
11419 TYPE_DEPENDENT_P (type) = dependent_type_p_r (type);
11420 TYPE_DEPENDENT_P_VALID (type) = 1;
11423 return TYPE_DEPENDENT_P (type);
11426 /* Returns TRUE if EXPRESSION is dependent, according to CRITERION. */
11429 dependent_scope_ref_p (tree expression, bool criterion (tree))
11434 my_friendly_assert (TREE_CODE (expression) == SCOPE_REF, 20030714);
11436 if (!TYPE_P (TREE_OPERAND (expression, 0)))
11439 scope = TREE_OPERAND (expression, 0);
11440 name = TREE_OPERAND (expression, 1);
11444 An id-expression is type-dependent if it contains a
11445 nested-name-specifier that contains a class-name that names a
11447 /* The suggested resolution to Core Issue 2 implies that if the
11448 qualifying type is the current class, then we must peek
11451 && currently_open_class (scope)
11452 && !criterion (name))
11454 if (dependent_type_p (scope))
11460 /* Returns TRUE if the EXPRESSION is value-dependent, in the sense of
11461 [temp.dep.constexpr] */
11464 value_dependent_expression_p (tree expression)
11466 if (!processing_template_decl)
11469 /* A name declared with a dependent type. */
11470 if (TREE_CODE (expression) == IDENTIFIER_NODE
11471 || (DECL_P (expression)
11472 && type_dependent_expression_p (expression)))
11474 /* A non-type template parameter. */
11475 if ((TREE_CODE (expression) == CONST_DECL
11476 && DECL_TEMPLATE_PARM_P (expression))
11477 || TREE_CODE (expression) == TEMPLATE_PARM_INDEX)
11479 /* A constant with integral or enumeration type and is initialized
11480 with an expression that is value-dependent. */
11481 if (TREE_CODE (expression) == VAR_DECL
11482 && DECL_INITIAL (expression)
11483 && INTEGRAL_OR_ENUMERATION_TYPE_P (TREE_TYPE (expression))
11484 && value_dependent_expression_p (DECL_INITIAL (expression)))
11486 /* These expressions are value-dependent if the type to which the
11487 cast occurs is dependent or the expression being casted is
11488 value-dependent. */
11489 if (TREE_CODE (expression) == DYNAMIC_CAST_EXPR
11490 || TREE_CODE (expression) == STATIC_CAST_EXPR
11491 || TREE_CODE (expression) == CONST_CAST_EXPR
11492 || TREE_CODE (expression) == REINTERPRET_CAST_EXPR
11493 || TREE_CODE (expression) == CAST_EXPR)
11495 if (dependent_type_p (TREE_TYPE (expression)))
11497 /* A functional cast has a list of operands. */
11498 expression = TREE_OPERAND (expression, 0);
11499 if (TREE_CODE (expression) == TREE_LIST)
11503 if (value_dependent_expression_p (TREE_VALUE (expression)))
11505 expression = TREE_CHAIN (expression);
11507 while (expression);
11511 return value_dependent_expression_p (expression);
11513 /* A `sizeof' expression is value-dependent if the operand is
11515 if (TREE_CODE (expression) == SIZEOF_EXPR
11516 || TREE_CODE (expression) == ALIGNOF_EXPR)
11518 expression = TREE_OPERAND (expression, 0);
11519 if (TYPE_P (expression))
11520 return dependent_type_p (expression);
11521 return type_dependent_expression_p (expression);
11523 if (TREE_CODE (expression) == SCOPE_REF)
11524 return dependent_scope_ref_p (expression, value_dependent_expression_p);
11525 /* A constant expression is value-dependent if any subexpression is
11526 value-dependent. */
11527 if (IS_EXPR_CODE_CLASS (TREE_CODE_CLASS (TREE_CODE (expression))))
11529 switch (TREE_CODE_CLASS (TREE_CODE (expression)))
11532 return (value_dependent_expression_p
11533 (TREE_OPERAND (expression, 0)));
11536 return ((value_dependent_expression_p
11537 (TREE_OPERAND (expression, 0)))
11538 || (value_dependent_expression_p
11539 (TREE_OPERAND (expression, 1))));
11543 for (i = 0; i < first_rtl_op (TREE_CODE (expression)); ++i)
11544 /* In some cases, some of the operands may be missing.
11545 (For example, in the case of PREDECREMENT_EXPR, the
11546 amount to increment by may be missing.) That doesn't
11547 make the expression dependent. */
11548 if (TREE_OPERAND (expression, i)
11549 && (value_dependent_expression_p
11550 (TREE_OPERAND (expression, i))))
11557 /* The expression is not value-dependent. */
11561 /* Returns TRUE if the EXPRESSION is type-dependent, in the sense of
11562 [temp.dep.expr]. */
11565 type_dependent_expression_p (tree expression)
11567 if (!processing_template_decl)
11570 if (expression == error_mark_node)
11573 /* An unresolved name is always dependent. */
11574 if (TREE_CODE (expression) == IDENTIFIER_NODE)
11577 /* Some expression forms are never type-dependent. */
11578 if (TREE_CODE (expression) == PSEUDO_DTOR_EXPR
11579 || TREE_CODE (expression) == SIZEOF_EXPR
11580 || TREE_CODE (expression) == ALIGNOF_EXPR
11581 || TREE_CODE (expression) == TYPEID_EXPR
11582 || TREE_CODE (expression) == DELETE_EXPR
11583 || TREE_CODE (expression) == VEC_DELETE_EXPR
11584 || TREE_CODE (expression) == THROW_EXPR)
11587 /* The types of these expressions depends only on the type to which
11588 the cast occurs. */
11589 if (TREE_CODE (expression) == DYNAMIC_CAST_EXPR
11590 || TREE_CODE (expression) == STATIC_CAST_EXPR
11591 || TREE_CODE (expression) == CONST_CAST_EXPR
11592 || TREE_CODE (expression) == REINTERPRET_CAST_EXPR
11593 || TREE_CODE (expression) == CAST_EXPR)
11594 return dependent_type_p (TREE_TYPE (expression));
11596 /* The types of these expressions depends only on the type created
11597 by the expression. */
11598 if (TREE_CODE (expression) == NEW_EXPR
11599 || TREE_CODE (expression) == VEC_NEW_EXPR)
11601 /* For NEW_EXPR tree nodes created inside a template, either
11602 the object type itself or a TREE_LIST may appear as the
11604 tree type = TREE_OPERAND (expression, 1);
11605 if (TREE_CODE (type) == TREE_LIST)
11606 /* This is an array type. We need to check array dimensions
11608 return dependent_type_p (TREE_VALUE (TREE_PURPOSE (type)))
11609 || value_dependent_expression_p
11610 (TREE_OPERAND (TREE_VALUE (type), 1));
11612 return dependent_type_p (type);
11615 if (TREE_CODE (expression) == SCOPE_REF
11616 && dependent_scope_ref_p (expression,
11617 type_dependent_expression_p))
11620 if (TREE_CODE (expression) == FUNCTION_DECL
11621 && DECL_LANG_SPECIFIC (expression)
11622 && DECL_TEMPLATE_INFO (expression)
11623 && (any_dependent_template_arguments_p
11624 (INNERMOST_TEMPLATE_ARGS (DECL_TI_ARGS (expression)))))
11627 if (TREE_TYPE (expression) == unknown_type_node)
11629 if (TREE_CODE (expression) == ADDR_EXPR)
11630 return type_dependent_expression_p (TREE_OPERAND (expression, 0));
11631 if (TREE_CODE (expression) == COMPONENT_REF)
11633 if (type_dependent_expression_p (TREE_OPERAND (expression, 0)))
11635 expression = TREE_OPERAND (expression, 1);
11636 if (TREE_CODE (expression) == IDENTIFIER_NODE)
11640 if (TREE_CODE (expression) == BASELINK)
11641 expression = BASELINK_FUNCTIONS (expression);
11642 if (TREE_CODE (expression) == TEMPLATE_ID_EXPR)
11644 if (any_dependent_template_arguments_p
11645 (TREE_OPERAND (expression, 1)))
11647 expression = TREE_OPERAND (expression, 0);
11649 if (TREE_CODE (expression) == OVERLOAD)
11653 if (type_dependent_expression_p (OVL_CURRENT (expression)))
11655 expression = OVL_NEXT (expression);
11662 return (dependent_type_p (TREE_TYPE (expression)));
11665 /* Returns TRUE if ARGS (a TREE_LIST of arguments to a function call)
11666 contains a type-dependent expression. */
11669 any_type_dependent_arguments_p (tree args)
11673 tree arg = TREE_VALUE (args);
11675 if (type_dependent_expression_p (arg))
11677 args = TREE_CHAIN (args);
11682 /* Returns TRUE if the ARG (a template argument) is dependent. */
11685 dependent_template_arg_p (tree arg)
11687 if (!processing_template_decl)
11690 if (TREE_CODE (arg) == TEMPLATE_DECL
11691 || TREE_CODE (arg) == TEMPLATE_TEMPLATE_PARM)
11692 return dependent_template_p (arg);
11693 else if (TYPE_P (arg))
11694 return dependent_type_p (arg);
11696 return (type_dependent_expression_p (arg)
11697 || value_dependent_expression_p (arg));
11700 /* Returns true if ARGS (a collection of template arguments) contains
11701 any dependent arguments. */
11704 any_dependent_template_arguments_p (tree args)
11711 for (i = 0; i < TREE_VEC_LENGTH (args); ++i)
11712 if (dependent_template_arg_p (TREE_VEC_ELT (args, i)))
11718 /* Returns TRUE if the template TMPL is dependent. */
11721 dependent_template_p (tree tmpl)
11723 /* Template template parameters are dependent. */
11724 if (DECL_TEMPLATE_TEMPLATE_PARM_P (tmpl)
11725 || TREE_CODE (tmpl) == TEMPLATE_TEMPLATE_PARM)
11727 /* So are qualified names that have not been looked up. */
11728 if (TREE_CODE (tmpl) == SCOPE_REF)
11730 /* So are member templates of dependent classes. */
11731 if (TYPE_P (CP_DECL_CONTEXT (tmpl)))
11732 return dependent_type_p (DECL_CONTEXT (tmpl));
11736 /* Returns TRUE if the specialization TMPL<ARGS> is dependent. */
11739 dependent_template_id_p (tree tmpl, tree args)
11741 return (dependent_template_p (tmpl)
11742 || any_dependent_template_arguments_p (args));
11745 /* TYPE is a TYPENAME_TYPE. Returns the ordinary TYPE to which the
11746 TYPENAME_TYPE corresponds. Returns ERROR_MARK_NODE if no such TYPE
11747 can be found. Note that this function peers inside uninstantiated
11748 templates and therefore should be used only in extremely limited
11752 resolve_typename_type (tree type, bool only_current_p)
11759 my_friendly_assert (TREE_CODE (type) == TYPENAME_TYPE,
11762 scope = TYPE_CONTEXT (type);
11763 name = TYPE_IDENTIFIER (type);
11765 /* If the SCOPE is itself a TYPENAME_TYPE, then we need to resolve
11766 it first before we can figure out what NAME refers to. */
11767 if (TREE_CODE (scope) == TYPENAME_TYPE)
11768 scope = resolve_typename_type (scope, only_current_p);
11769 /* If we don't know what SCOPE refers to, then we cannot resolve the
11771 if (scope == error_mark_node || TREE_CODE (scope) == TYPENAME_TYPE)
11772 return error_mark_node;
11773 /* If the SCOPE is a template type parameter, we have no way of
11774 resolving the name. */
11775 if (TREE_CODE (scope) == TEMPLATE_TYPE_PARM)
11777 /* If the SCOPE is not the current instantiation, there's no reason
11778 to look inside it. */
11779 if (only_current_p && !currently_open_class (scope))
11780 return error_mark_node;
11781 /* If SCOPE is a partial instantiation, it will not have a valid
11782 TYPE_FIELDS list, so use the original template. */
11783 scope = CLASSTYPE_PRIMARY_TEMPLATE_TYPE (scope);
11784 /* Enter the SCOPE so that name lookup will be resolved as if we
11785 were in the class definition. In particular, SCOPE will no
11786 longer be considered a dependent type. */
11787 push_scope (scope);
11788 /* Look up the declaration. */
11789 decl = lookup_member (scope, name, /*protect=*/0, /*want_type=*/true);
11790 /* Obtain the set of qualifiers applied to the TYPE. */
11791 quals = cp_type_quals (type);
11792 /* For a TYPENAME_TYPE like "typename X::template Y<T>", we want to
11793 find a TEMPLATE_DECL. Otherwise, we want to find a TYPE_DECL. */
11795 type = error_mark_node;
11796 else if (TREE_CODE (TYPENAME_TYPE_FULLNAME (type)) == IDENTIFIER_NODE
11797 && TREE_CODE (decl) == TYPE_DECL)
11798 type = TREE_TYPE (decl);
11799 else if (TREE_CODE (TYPENAME_TYPE_FULLNAME (type)) == TEMPLATE_ID_EXPR
11800 && DECL_CLASS_TEMPLATE_P (decl))
11804 /* Obtain the template and the arguments. */
11805 tmpl = TREE_OPERAND (TYPENAME_TYPE_FULLNAME (type), 0);
11806 args = TREE_OPERAND (TYPENAME_TYPE_FULLNAME (type), 1);
11807 /* Instantiate the template. */
11808 type = lookup_template_class (tmpl, args, NULL_TREE, NULL_TREE,
11809 /*entering_scope=*/0, tf_error | tf_user);
11812 type = error_mark_node;
11813 /* Qualify the resulting type. */
11814 if (type != error_mark_node && quals)
11815 type = cp_build_qualified_type (type, quals);
11816 /* Leave the SCOPE. */
11822 /* EXPR is an expression which is not type-dependent. Return a proxy
11823 for EXPR that can be used to compute the types of larger
11824 expressions containing EXPR. */
11827 build_non_dependent_expr (tree expr)
11829 /* Preserve null pointer constants so that the type of things like
11830 "p == 0" where "p" is a pointer can be determined. */
11831 if (null_ptr_cst_p (expr))
11833 /* Preserve OVERLOADs; the functions must be available to resolve
11835 if (TREE_CODE (expr) == OVERLOAD)
11837 /* Preserve string constants; conversions from string constants to
11838 "char *" are allowed, even though normally a "const char *"
11839 cannot be used to initialize a "char *". */
11840 if (TREE_CODE (expr) == STRING_CST)
11843 if (TREE_CODE (expr) == COND_EXPR)
11844 return build (COND_EXPR,
11846 TREE_OPERAND (expr, 0),
11847 build_non_dependent_expr (TREE_OPERAND (expr, 1)),
11848 build_non_dependent_expr (TREE_OPERAND (expr, 2)));
11849 if (TREE_CODE (expr) == COMPOUND_EXPR
11850 && !COMPOUND_EXPR_OVERLOADED (expr))
11851 return build (COMPOUND_EXPR,
11853 TREE_OPERAND (expr, 0),
11854 build_non_dependent_expr (TREE_OPERAND (expr, 1)));
11856 /* Otherwise, build a NON_DEPENDENT_EXPR.
11858 REFERENCE_TYPEs are not stripped for expressions in templates
11859 because doing so would play havoc with mangling. Consider, for
11862 template <typename T> void f<T& g>() { g(); }
11864 In the body of "f", the expression for "g" will have
11865 REFERENCE_TYPE, even though the standard says that it should
11866 not. The reason is that we must preserve the syntactic form of
11867 the expression so that mangling (say) "f<g>" inside the body of
11868 "f" works out correctly. Therefore, the REFERENCE_TYPE is
11870 return build1 (NON_DEPENDENT_EXPR, non_reference (TREE_TYPE (expr)), expr);
11873 /* ARGS is a TREE_LIST of expressions as arguments to a function call.
11874 Return a new TREE_LIST with the various arguments replaced with
11875 equivalent non-dependent expressions. */
11878 build_non_dependent_args (tree args)
11883 new_args = NULL_TREE;
11884 for (a = args; a; a = TREE_CHAIN (a))
11885 new_args = tree_cons (NULL_TREE,
11886 build_non_dependent_expr (TREE_VALUE (a)),
11888 return nreverse (new_args);
11891 #include "gt-cp-pt.h"