/* Handle parameterized types (templates) for GNU C++. Copyright (C) 1992, 93-97, 1998 Free Software Foundation, Inc. Written by Ken Raeburn (raeburn@cygnus.com) while at Watchmaker Computing. Rewritten by Jason Merrill (jason@cygnus.com). This file is part of GNU CC. GNU CC is free software; you can redistribute it and/or modify it under the terms of the GNU General Public License as published by the Free Software Foundation; either version 2, or (at your option) any later version. GNU CC is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for more details. You should have received a copy of the GNU General Public License along with GNU CC; see the file COPYING. If not, write to the Free Software Foundation, 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. */ /* Known bugs or deficiencies include: all methods must be provided in header files; can't use a source file that contains only the method templates and "just win". */ #include "config.h" #include "system.h" #include "obstack.h" #include "tree.h" #include "flags.h" #include "cp-tree.h" #include "decl.h" #include "parse.h" #include "lex.h" #include "output.h" #include "defaults.h" #include "except.h" #include "toplev.h" /* The type of functions taking a tree, and some additional data, and returning an int. */ typedef int (*tree_fn_t) PROTO((tree, void*)); extern struct obstack permanent_obstack; extern int lineno; extern char *input_filename; struct pending_inline *pending_template_expansions; tree current_template_parms; HOST_WIDE_INT processing_template_decl; tree pending_templates; static tree *template_tail = &pending_templates; tree maybe_templates; static tree *maybe_template_tail = &maybe_templates; int minimal_parse_mode; int processing_specialization; int processing_explicit_instantiation; int processing_template_parmlist; static int template_header_count; static tree saved_trees; #define obstack_chunk_alloc xmalloc #define obstack_chunk_free free #define UNIFY_ALLOW_NONE 0 #define UNIFY_ALLOW_MORE_CV_QUAL 1 #define UNIFY_ALLOW_LESS_CV_QUAL 2 #define UNIFY_ALLOW_DERIVED 4 #define UNIFY_ALLOW_INTEGER 8 static int unify PROTO((tree, tree, tree, tree, int, int*)); static int resolve_overloaded_unification PROTO((tree, tree, tree, tree, unification_kind_t, int, int*)); static int try_one_overload PROTO((tree, tree, tree, tree, tree, unification_kind_t, int, int*)); static int unify PROTO((tree, tree, tree, tree, int, int*)); static void add_pending_template PROTO((tree)); static int push_tinst_level PROTO((tree)); static tree classtype_mangled_name PROTO((tree)); static char *mangle_class_name_for_template PROTO((char *, tree, tree)); static tree tsubst_expr_values PROTO((tree, tree)); static int list_eq PROTO((tree, tree)); static tree get_class_bindings PROTO((tree, tree, tree)); static tree coerce_template_parms PROTO((tree, tree, tree, int, int)); static void tsubst_enum PROTO((tree, tree, tree)); static tree add_to_template_args PROTO((tree, tree)); static tree add_outermost_template_args PROTO((tree, tree)); static void maybe_adjust_types_for_deduction PROTO((unification_kind_t, tree*, tree*)); static int type_unification_real PROTO((tree, tree, tree, tree, int, unification_kind_t, int, int*)); static void note_template_header PROTO((int)); static tree maybe_fold_nontype_arg PROTO((tree)); static tree convert_nontype_argument PROTO((tree, tree)); static tree convert_template_argument PROTO ((tree, tree, tree, int, int , tree)); static tree get_bindings_overload PROTO((tree, tree, tree)); static int for_each_template_parm PROTO((tree, tree_fn_t, void*)); static tree build_template_parm_index PROTO((int, int, int, tree, tree)); static int inline_needs_template_parms PROTO((tree)); static void push_inline_template_parms_recursive PROTO((tree, int)); static tree retrieve_specialization PROTO((tree, tree)); static tree register_specialization PROTO((tree, tree, tree)); static int unregister_specialization PROTO((tree, tree)); static void print_candidates PROTO((tree)); static tree reduce_template_parm_level PROTO((tree, tree, int)); static tree build_template_decl PROTO((tree, tree)); static int mark_template_parm PROTO((tree, void *)); static tree tsubst_friend_function PROTO((tree, tree)); static tree tsubst_friend_class PROTO((tree, tree)); static tree get_bindings_real PROTO((tree, tree, tree, int)); static int template_decl_level PROTO((tree)); static tree maybe_get_template_decl_from_type_decl PROTO((tree)); static int check_cv_quals_for_unify PROTO((int, tree, tree)); static tree tsubst_template_arg_vector PROTO((tree, tree)); static tree tsubst_template_parms PROTO((tree, tree)); static void regenerate_decl_from_template PROTO((tree, tree)); static tree most_specialized PROTO((tree, tree, tree)); static tree most_specialized_class PROTO((tree, tree)); static tree most_general_template PROTO((tree)); static void set_mangled_name_for_template_decl PROTO((tree)); static int template_class_depth_real PROTO((tree, int)); static tree tsubst_aggr_type PROTO((tree, tree, tree, int)); static tree tsubst_decl PROTO((tree, tree, tree, tree)); static tree tsubst_arg_types PROTO((tree, tree, tree)); static void check_specialization_scope PROTO((void)); static tree process_partial_specialization PROTO((tree)); static void set_current_access_from_decl PROTO((tree)); static void check_default_tmpl_args PROTO((tree, tree, int, int)); /* We use TREE_VECs to hold template arguments. If there is only one level of template arguments, then the TREE_VEC contains the arguments directly. If there is more than one level of template arguments, then each entry in the TREE_VEC is itself a TREE_VEC, containing the template arguments for a single level. The first entry in the outer TREE_VEC is the outermost level of template parameters; the last is the innermost. It is incorrect to ever form a template argument vector containing only one level of arguments, but which is a TREE_VEC containing as its only entry the TREE_VEC for that level. */ /* Non-zero if the template arguments is actually a vector of vectors, rather than just a vector. */ #define TMPL_ARGS_HAVE_MULTIPLE_LEVELS(NODE) \ (NODE != NULL_TREE \ && TREE_CODE (NODE) == TREE_VEC \ && TREE_VEC_LENGTH (NODE) > 0 \ && TREE_VEC_ELT (NODE, 0) != NULL_TREE \ && TREE_CODE (TREE_VEC_ELT (NODE, 0)) == TREE_VEC) /* The depth of a template argument vector. When called directly by the parser, we use a TREE_LIST rather than a TREE_VEC to represent template arguments. In fact, we may even see NULL_TREE if there are no template arguments. In both of those cases, there is only one level of template arguments. */ #define TMPL_ARGS_DEPTH(NODE) \ (TMPL_ARGS_HAVE_MULTIPLE_LEVELS (NODE) ? TREE_VEC_LENGTH (NODE) : 1) /* The LEVELth level of the template ARGS. Note that template parameter levels are indexed from 1, not from 0. */ #define TMPL_ARGS_LEVEL(ARGS, LEVEL) \ (TMPL_ARGS_HAVE_MULTIPLE_LEVELS (ARGS) \ ? TREE_VEC_ELT ((ARGS), (LEVEL) - 1) : ARGS) /* Set the LEVELth level of the template ARGS to VAL. This macro does not work with single-level argument vectors. */ #define SET_TMPL_ARGS_LEVEL(ARGS, LEVEL, VAL) \ (TREE_VEC_ELT ((ARGS), (LEVEL) - 1) = (VAL)) /* Accesses the IDXth parameter in the LEVELth level of the ARGS. */ #define TMPL_ARG(ARGS, LEVEL, IDX) \ (TREE_VEC_ELT (TMPL_ARGS_LEVEL (ARGS, LEVEL), IDX)) /* Set the IDXth element in the LEVELth level of ARGS to VAL. This macro does not work with single-level argument vectors. */ #define SET_TMPL_ARG(ARGS, LEVEL, IDX, VAL) \ (TREE_VEC_ELT (TREE_VEC_ELT ((ARGS), (LEVEL) - 1), (IDX)) = (VAL)) /* Given a single level of template arguments in NODE, return the number of arguments. */ #define NUM_TMPL_ARGS(NODE) \ ((NODE) == NULL_TREE ? 0 \ : (TREE_CODE (NODE) == TREE_VEC \ ? TREE_VEC_LENGTH (NODE) : list_length (NODE))) /* The number of levels of template parameters given by NODE. */ #define TMPL_PARMS_DEPTH(NODE) \ (TREE_INT_CST_HIGH (TREE_PURPOSE (NODE))) /* Do any processing required when DECL (a member template declaration using TEMPLATE_PARAMETERS as its innermost parameter list) is finished. Returns the TEMPLATE_DECL corresponding to DECL, unless it is a specialization, in which case the DECL itself is returned. */ tree finish_member_template_decl (decl) tree decl; { if (decl == NULL_TREE || decl == void_type_node) return NULL_TREE; else if (decl == error_mark_node) /* By returning NULL_TREE, the parser will just ignore this declaration. We have already issued the error. */ return NULL_TREE; else if (TREE_CODE (decl) == TREE_LIST) { /* Assume that the class is the only declspec. */ decl = TREE_VALUE (decl); if (IS_AGGR_TYPE (decl) && CLASSTYPE_TEMPLATE_INFO (decl) && ! CLASSTYPE_TEMPLATE_SPECIALIZATION (decl)) { tree tmpl = CLASSTYPE_TI_TEMPLATE (decl); check_member_template (tmpl); return tmpl; } return NULL_TREE; } else if (DECL_TEMPLATE_INFO (decl)) { if (!DECL_TEMPLATE_SPECIALIZATION (decl)) { check_member_template (DECL_TI_TEMPLATE (decl)); return DECL_TI_TEMPLATE (decl); } else return decl; } else cp_error ("invalid member template declaration `%D'", decl); return error_mark_node; } /* Returns the template nesting level of the indicated class TYPE. For example, in: template <class T> struct A { template <class U> struct B {}; }; A<T>::B<U> has depth two, while A<T> has depth one. Both A<T>::B<int> and A<int>::B<U> have depth one, if COUNT_SPECIALIZATIONS is 0 or if they are instantiations, not specializations. This function is guaranteed to return 0 if passed NULL_TREE so that, for example, `template_class_depth (current_class_type)' is always safe. */ int template_class_depth_real (type, count_specializations) tree type; int count_specializations; { int depth; for (depth = 0; type && TREE_CODE (type) != NAMESPACE_DECL; type = (TREE_CODE (type) == FUNCTION_DECL) ? DECL_REAL_CONTEXT (type) : TYPE_CONTEXT (type)) { if (TREE_CODE (type) != FUNCTION_DECL) { if (CLASSTYPE_TEMPLATE_INFO (type) && PRIMARY_TEMPLATE_P (CLASSTYPE_TI_TEMPLATE (type)) && ((count_specializations && CLASSTYPE_TEMPLATE_SPECIALIZATION (type)) || uses_template_parms (CLASSTYPE_TI_ARGS (type)))) ++depth; } else { if (DECL_TEMPLATE_INFO (type) && PRIMARY_TEMPLATE_P (DECL_TI_TEMPLATE (type)) && ((count_specializations && DECL_TEMPLATE_SPECIALIZATION (type)) || uses_template_parms (DECL_TI_ARGS (type)))) ++depth; } } return depth; } /* Returns the template nesting level of the indicated class TYPE. Like template_class_depth_real, but instantiations do not count in the depth. */ int template_class_depth (type) tree type; { return template_class_depth_real (type, /*count_specializations=*/0); } /* Returns 1 if processing DECL as part of do_pending_inlines needs us to push template parms. */ static int inline_needs_template_parms (decl) tree decl; { if (! DECL_TEMPLATE_INFO (decl)) return 0; return (TMPL_PARMS_DEPTH (DECL_TEMPLATE_PARMS (most_general_template (decl))) > (processing_template_decl + DECL_TEMPLATE_SPECIALIZATION (decl))); } /* Subroutine of maybe_begin_member_template_processing. Push the template parms in PARMS, starting from LEVELS steps into the chain, and ending at the beginning, since template parms are listed innermost first. */ static void push_inline_template_parms_recursive (parmlist, levels) tree parmlist; int levels; { tree parms = TREE_VALUE (parmlist); int i; if (levels > 1) push_inline_template_parms_recursive (TREE_CHAIN (parmlist), levels - 1); ++processing_template_decl; current_template_parms = tree_cons (build_int_2 (0, processing_template_decl), parms, current_template_parms); TEMPLATE_PARMS_FOR_INLINE (current_template_parms) = 1; pushlevel (0); for (i = 0; i < TREE_VEC_LENGTH (parms); ++i) { tree parm = TREE_VALUE (TREE_VEC_ELT (parms, i)); my_friendly_assert (TREE_CODE_CLASS (TREE_CODE (parm)) == 'd', 0); switch (TREE_CODE (parm)) { case TYPE_DECL: case TEMPLATE_DECL: pushdecl (parm); break; case PARM_DECL: { /* Make a CONST_DECL as is done in process_template_parm. */ tree decl = build_decl (CONST_DECL, DECL_NAME (parm), TREE_TYPE (parm)); DECL_INITIAL (decl) = DECL_INITIAL (parm); pushdecl (decl); } break; default: my_friendly_abort (0); } } } /* Restore the template parameter context for a member template or a friend template defined in a class definition. */ void maybe_begin_member_template_processing (decl) tree decl; { tree parms; int levels; if (! inline_needs_template_parms (decl)) return; parms = DECL_TEMPLATE_PARMS (most_general_template (decl)); levels = TMPL_PARMS_DEPTH (parms) - processing_template_decl; if (DECL_TEMPLATE_SPECIALIZATION (decl)) { --levels; parms = TREE_CHAIN (parms); } push_inline_template_parms_recursive (parms, levels); } /* Undo the effects of begin_member_template_processing. */ void maybe_end_member_template_processing () { if (! processing_template_decl) return; while (current_template_parms && TEMPLATE_PARMS_FOR_INLINE (current_template_parms)) { --processing_template_decl; current_template_parms = TREE_CHAIN (current_template_parms); poplevel (0, 0, 0); } } /* Returns non-zero iff T is a member template function. We must be careful as in template <class T> class C { void f(); } Here, f is a template function, and a member, but not a member template. This function does not concern itself with the origin of T, only its present state. So if we have template <class T> class C { template <class U> void f(U); } then neither C<int>::f<char> nor C<T>::f<double> is considered to be a member template. */ int is_member_template (t) tree t; { if (TREE_CODE (t) != FUNCTION_DECL && !DECL_FUNCTION_TEMPLATE_P (t)) /* Anything that isn't a function or a template function is certainly not a member template. */ return 0; /* A local class can't have member templates. */ if (hack_decl_function_context (t)) return 0; if ((DECL_FUNCTION_MEMBER_P (t) && !DECL_TEMPLATE_SPECIALIZATION (t)) || (TREE_CODE (t) == TEMPLATE_DECL && DECL_FUNCTION_MEMBER_P (DECL_TEMPLATE_RESULT (t)))) { tree tmpl; if (DECL_FUNCTION_TEMPLATE_P (t)) tmpl = t; else if (DECL_TEMPLATE_INFO (t) && DECL_FUNCTION_TEMPLATE_P (DECL_TI_TEMPLATE (t))) tmpl = DECL_TI_TEMPLATE (t); else tmpl = NULL_TREE; if (tmpl /* If there are more levels of template parameters than there are template classes surrounding the declaration, then we have a member template. */ && (TMPL_PARMS_DEPTH (DECL_TEMPLATE_PARMS (tmpl)) > template_class_depth (DECL_CLASS_CONTEXT (t)))) return 1; } return 0; } #if 0 /* UNUSED */ /* Returns non-zero iff T is a member template class. See is_member_template for a description of what precisely constitutes a member template. */ int is_member_template_class (t) tree t; { if (!DECL_CLASS_TEMPLATE_P (t)) /* Anything that isn't a class template, is certainly not a member template. */ return 0; if (!DECL_CLASS_SCOPE_P (t)) /* Anything whose context isn't a class type is surely not a member template. */ return 0; /* If there are more levels of template parameters than there are template classes surrounding the declaration, then we have a member template. */ return (TMPL_PARMS_DEPTH (DECL_TEMPLATE_PARMS (t)) > template_class_depth (DECL_CONTEXT (t))); } #endif /* Return a new template argument vector which contains all of ARGS, but has as its innermost set of arguments the EXTRA_ARGS. The resulting vector will be built on a temporary obstack, and so must be explicitly copied to the permanent obstack, if required. */ static tree add_to_template_args (args, extra_args) tree args; tree extra_args; { tree new_args; int extra_depth; int i; int j; extra_depth = TMPL_ARGS_DEPTH (extra_args); new_args = make_temp_vec (TMPL_ARGS_DEPTH (args) + extra_depth); for (i = 1; i <= TMPL_ARGS_DEPTH (args); ++i) SET_TMPL_ARGS_LEVEL (new_args, i, TMPL_ARGS_LEVEL (args, i)); for (j = 1; j <= extra_depth; ++j, ++i) SET_TMPL_ARGS_LEVEL (new_args, i, TMPL_ARGS_LEVEL (extra_args, j)); return new_args; } /* Like add_to_template_args, but only the outermost ARGS are added to the EXTRA_ARGS. In particular, all but TMPL_ARGS_DEPTH (EXTRA_ARGS) levels are added. This function is used to combine the template arguments from a partial instantiation with the template arguments used to attain the full instantiation from the partial instantiation. */ static tree add_outermost_template_args (args, extra_args) tree args; tree extra_args; { tree new_args; /* If there are more levels of EXTRA_ARGS than there are ARGS, something very fishy is going on. */ my_friendly_assert (TMPL_ARGS_DEPTH (args) >= TMPL_ARGS_DEPTH (extra_args), 0); /* If *all* the new arguments will be the EXTRA_ARGS, just return them. */ if (TMPL_ARGS_DEPTH (args) == TMPL_ARGS_DEPTH (extra_args)) return extra_args; /* For the moment, we make ARGS look like it contains fewer levels. */ TREE_VEC_LENGTH (args) -= TMPL_ARGS_DEPTH (extra_args); new_args = add_to_template_args (args, extra_args); /* Now, we restore ARGS to its full dimensions. */ TREE_VEC_LENGTH (args) += TMPL_ARGS_DEPTH (extra_args); return new_args; } /* We've got a template header coming up; push to a new level for storing the parms. */ void begin_template_parm_list () { /* We use a non-tag-transparent scope here, which causes pushtag to put tags in this scope, rather than in the enclosing class or namespace scope. This is the right thing, since we want TEMPLATE_DECLS, and not TYPE_DECLS for template classes. For a global template class, push_template_decl handles putting the TEMPLATE_DECL into top-level scope. For a nested template class, e.g.: template <class T> struct S1 { template <class T> struct S2 {}; }; pushtag contains special code to call pushdecl_with_scope on the TEMPLATE_DECL for S2. */ pushlevel (0); declare_pseudo_global_level (); ++processing_template_decl; ++processing_template_parmlist; note_template_header (0); } /* This routine is called when a specialization is declared. If it is illegal to declare a specialization here, an error is reported. */ void check_specialization_scope () { tree scope = current_scope (); /* [temp.expl.spec] An explicit specialization shall be declared in the namespace of which the template is a member, or, for member templates, in the namespace of which the enclosing class or enclosing class template is a member. An explicit specialization of a member function, member class or static data member of a class template shall be declared in the namespace of which the class template is a member. */ if (scope && TREE_CODE (scope) != NAMESPACE_DECL) cp_error ("explicit specialization in non-namespace scope `%D'", scope); /* [temp.expl.spec] In an explicit specialization declaration for a member of a class template or a member template that appears in namespace scope, the member template and some of its enclosing class templates may remain unspecialized, except that the declaration shall not explicitly specialize a class member template if its enclosing class templates are not explicitly specialized as well. */ if (current_template_parms) cp_error ("enclosing class templates are not explicitly specialized"); } /* We've just seen template <>. */ void begin_specialization () { note_template_header (1); check_specialization_scope (); } /* Called at then end of processing a declaration preceeded by template<>. */ void end_specialization () { reset_specialization (); } /* Any template <>'s that we have seen thus far are not referring to a function specialization. */ void reset_specialization () { processing_specialization = 0; template_header_count = 0; } /* We've just seen a template header. If SPECIALIZATION is non-zero, it was of the form template <>. */ static void note_template_header (specialization) int specialization; { processing_specialization = specialization; template_header_count++; } /* We're beginning an explicit instantiation. */ void begin_explicit_instantiation () { ++processing_explicit_instantiation; } void end_explicit_instantiation () { my_friendly_assert(processing_explicit_instantiation > 0, 0); --processing_explicit_instantiation; } /* The TYPE is being declared. If it is a template type, that means it is a partial specialization. Do appropriate error-checking. */ void maybe_process_partial_specialization (type) tree type; { if (IS_AGGR_TYPE (type) && CLASSTYPE_USE_TEMPLATE (type)) { if (CLASSTYPE_IMPLICIT_INSTANTIATION (type) && TYPE_SIZE (type) == NULL_TREE) { SET_CLASSTYPE_TEMPLATE_SPECIALIZATION (type); if (processing_template_decl) push_template_decl (TYPE_MAIN_DECL (type)); } else if (CLASSTYPE_TEMPLATE_INSTANTIATION (type)) cp_error ("specialization of `%T' after instantiation", type); } } /* Retrieve the specialization (in the sense of [temp.spec] - a specialization is either an instantiation or an explicit specialization) of TMPL for the given template ARGS. If there is no such specialization, return NULL_TREE. The ARGS are a vector of arguments, or a vector of vectors of arguments, in the case of templates with more than one level of parameters. */ static tree retrieve_specialization (tmpl, args) tree tmpl; tree args; { tree s; my_friendly_assert (TREE_CODE (tmpl) == TEMPLATE_DECL, 0); /* There should be as many levels of arguments as there are levels of parameters. */ my_friendly_assert (TMPL_ARGS_DEPTH (args) == TMPL_PARMS_DEPTH (DECL_TEMPLATE_PARMS (tmpl)), 0); for (s = DECL_TEMPLATE_SPECIALIZATIONS (tmpl); s != NULL_TREE; s = TREE_CHAIN (s)) if (comp_template_args (TREE_PURPOSE (s), args)) return TREE_VALUE (s); return NULL_TREE; } /* Returns non-zero iff DECL is a specialization of TMPL. */ int is_specialization_of (decl, tmpl) tree decl; tree tmpl; { tree t; if (TREE_CODE (decl) == FUNCTION_DECL) { for (t = decl; t != NULL_TREE; t = DECL_TEMPLATE_INFO (t) ? DECL_TI_TEMPLATE (t) : NULL_TREE) if (t == tmpl) return 1; } else { my_friendly_assert (TREE_CODE (decl) == TYPE_DECL, 0); for (t = TREE_TYPE (decl); t != NULL_TREE; t = CLASSTYPE_USE_TEMPLATE (t) ? TREE_TYPE (CLASSTYPE_TI_TEMPLATE (t)) : NULL_TREE) if (same_type_p (TYPE_MAIN_VARIANT (t), TYPE_MAIN_VARIANT (TREE_TYPE (tmpl)))) return 1; } return 0; } /* Register the specialization SPEC as a specialization of TMPL with the indicated ARGS. Returns SPEC, or an equivalent prior declaration, if available. */ static tree register_specialization (spec, tmpl, args) tree spec; tree tmpl; tree args; { tree s; my_friendly_assert (TREE_CODE (tmpl) == TEMPLATE_DECL, 0); if (TREE_CODE (spec) == FUNCTION_DECL && uses_template_parms (DECL_TI_ARGS (spec))) /* This is the FUNCTION_DECL for a partial instantiation. Don't register it; we want the corresponding TEMPLATE_DECL instead. We use `uses_template_parms (DECL_TI_ARGS (spec))' rather than the more obvious `uses_template_parms (spec)' to avoid problems with default function arguments. In particular, given something like this: template <class T> void f(T t1, T t = T()) the default argument expression is not substituted for in an instantiation unless and until it is actually needed. */ return spec; /* There should be as many levels of arguments as there are levels of parameters. */ my_friendly_assert (TMPL_ARGS_DEPTH (args) == TMPL_PARMS_DEPTH (DECL_TEMPLATE_PARMS (tmpl)), 0); for (s = DECL_TEMPLATE_SPECIALIZATIONS (tmpl); s != NULL_TREE; s = TREE_CHAIN (s)) if (comp_template_args (TREE_PURPOSE (s), args)) { tree fn = TREE_VALUE (s); if (DECL_TEMPLATE_SPECIALIZATION (spec)) { if (DECL_TEMPLATE_INSTANTIATION (fn)) { if (TREE_USED (fn) || DECL_EXPLICIT_INSTANTIATION (fn)) { cp_error ("specialization of %D after instantiation", fn); return spec; } else { /* This situation should occur only if the first specialization is an implicit instantiation, the second is an explicit specialization, and the implicit instantiation has not yet been used. That situation can occur if we have implicitly instantiated a member function and then specialized it later. We can also wind up here if a friend declaration that looked like an instantiation turns out to be a specialization: template <class T> void foo(T); class S { friend void foo<>(int) }; template <> void foo(int); We transform the existing DECL in place so that any pointers to it become pointers to the updated declaration. If there was a definition for the template, but not for the specialization, we want this to look as if there is no definition, and vice versa. */ DECL_INITIAL (fn) = NULL_TREE; duplicate_decls (spec, fn); return fn; } } else if (DECL_TEMPLATE_SPECIALIZATION (fn)) { duplicate_decls (spec, fn); return fn; } } } DECL_TEMPLATE_SPECIALIZATIONS (tmpl) = perm_tree_cons (args, spec, DECL_TEMPLATE_SPECIALIZATIONS (tmpl)); return spec; } /* Unregister the specialization SPEC as a specialization of TMPL. Returns nonzero if the SPEC was listed as a specialization of TMPL. */ static int unregister_specialization (spec, tmpl) tree spec; tree tmpl; { tree* s; for (s = &DECL_TEMPLATE_SPECIALIZATIONS (tmpl); *s != NULL_TREE; s = &TREE_CHAIN (*s)) if (TREE_VALUE (*s) == spec) { *s = TREE_CHAIN (*s); return 1; } return 0; } /* Print the list of candidate FNS in an error message. */ static void print_candidates (fns) tree fns; { tree fn; char* str = "candidates are:"; for (fn = fns; fn != NULL_TREE; fn = TREE_CHAIN (fn)) { cp_error_at ("%s %+#D", str, TREE_VALUE (fn)); str = " "; } } /* Returns the template (one of the functions given by TEMPLATE_ID) which can be specialized to match the indicated DECL with the explicit template args given in TEMPLATE_ID. If NEED_MEMBER_TEMPLATE is true the function is a specialization of a member template. The template args (those explicitly specified and those deduced) are output in a newly created vector *TARGS_OUT. If it is impossible to determine the result, an error message is issued, unless COMPLAIN is 0. The DECL may be NULL_TREE if none is available. */ tree determine_specialization (template_id, decl, targs_out, need_member_template, complain) tree template_id; tree decl; tree* targs_out; int need_member_template; int complain; { tree fns, targs_in; tree templates = NULL_TREE; tree fn; *targs_out = NULL_TREE; if (template_id == error_mark_node) return error_mark_node; fns = TREE_OPERAND (template_id, 0); targs_in = TREE_OPERAND (template_id, 1); if (fns == error_mark_node) return error_mark_node; /* Check for baselinks. */ if (TREE_CODE (fns) == TREE_LIST) fns = TREE_VALUE (fns); for (; fns; fns = OVL_NEXT (fns)) { tree tmpl; fn = OVL_CURRENT (fns); if (!need_member_template && TREE_CODE (fn) == FUNCTION_DECL && DECL_FUNCTION_MEMBER_P (fn) && DECL_USE_TEMPLATE (fn) && DECL_TI_TEMPLATE (fn)) /* We can get here when processing something like: template <class T> class X { void f(); } template <> void X<int>::f() {} We're specializing a member function, but not a member template. */ tmpl = DECL_TI_TEMPLATE (fn); else if (TREE_CODE (fn) != TEMPLATE_DECL || (need_member_template && !is_member_template (fn))) continue; else tmpl = fn; if (list_length (targs_in) > DECL_NTPARMS (tmpl)) continue; if (decl == NULL_TREE) { /* Unify against ourselves to make sure that the args we have make sense and there aren't any undeducible parms. It's OK if not all the parms are specified; they might be deduced later. */ tree targs = get_bindings_overload (tmpl, DECL_RESULT (tmpl), targs_in); if (targs) /* Unification was successful. */ templates = scratch_tree_cons (targs, tmpl, templates); } else templates = scratch_tree_cons (NULL_TREE, tmpl, templates); } if (decl != NULL_TREE) { tree tmpl = most_specialized (templates, decl, targs_in); tree inner_args; tree tmpl_args; if (tmpl == error_mark_node) goto ambiguous; else if (tmpl == NULL_TREE) goto no_match; inner_args = get_bindings (tmpl, decl, targs_in); tmpl_args = DECL_TI_ARGS (DECL_RESULT (tmpl)); if (TMPL_ARGS_HAVE_MULTIPLE_LEVELS (tmpl_args)) { *targs_out = copy_node (tmpl_args); SET_TMPL_ARGS_LEVEL (*targs_out, TMPL_ARGS_DEPTH (*targs_out), inner_args); } else *targs_out = inner_args; return tmpl; } if (templates == NULL_TREE) { no_match: if (complain) { cp_error_at ("template-id `%D' for `%+D' does not match any template declaration", template_id, decl); return error_mark_node; } return NULL_TREE; } else if (TREE_CHAIN (templates) != NULL_TREE || uses_template_parms (TREE_PURPOSE (templates))) { ambiguous: if (complain) { cp_error_at ("ambiguous template specialization `%D' for `%+D'", template_id, decl); print_candidates (templates); return error_mark_node; } return NULL_TREE; } /* We have one, and exactly one, match. */ *targs_out = TREE_PURPOSE (templates); return TREE_VALUE (templates); } /* Check to see if the function just declared, as indicated in DECLARATOR, and in DECL, is a specialization of a function template. We may also discover that the declaration is an explicit instantiation at this point. Returns DECL, or an equivalent declaration that should be used instead. FLAGS is a bitmask consisting of the following flags: 2: The function has a definition. 4: The function is a friend. The TEMPLATE_COUNT is the number of references to qualifying template classes that appeared in the name of the function. For example, in template <class T> struct S { void f(); }; void S<int>::f(); the TEMPLATE_COUNT would be 1. However, explicitly specialized classes are not counted in the TEMPLATE_COUNT, so that in template <class T> struct S {}; template <> struct S<int> { void f(); } template <> void S<int>::f(); the TEMPLATE_COUNT would be 0. (Note that this declaration is illegal; there should be no template <>.) If the function is a specialization, it is marked as such via DECL_TEMPLATE_SPECIALIZATION. Furthermore, its DECL_TEMPLATE_INFO is set up correctly, and it is added to the list of specializations for that template. */ tree check_explicit_specialization (declarator, decl, template_count, flags) tree declarator; tree decl; int template_count; int flags; { int have_def = flags & 2; int is_friend = flags & 4; int specialization = 0; int explicit_instantiation = 0; int member_specialization = 0; tree ctype = DECL_CLASS_CONTEXT (decl); tree dname = DECL_NAME (decl); if (processing_specialization) { /* The last template header was of the form template <>. */ if (template_header_count > template_count) { /* There were more template headers than qualifying template classes. */ if (template_header_count - template_count > 1) /* There shouldn't be that many template parameter lists. There can be at most one parameter list for every qualifying class, plus one for the function itself. */ cp_error ("too many template parameter lists in declaration of `%D'", decl); SET_DECL_TEMPLATE_SPECIALIZATION (decl); if (ctype) member_specialization = 1; else specialization = 1; } else if (template_header_count == template_count) { /* The counts are equal. So, this might be a specialization, but it is not a specialization of a member template. It might be something like template <class T> struct S { void f(int i); }; template <> void S<int>::f(int i) {} */ specialization = 1; SET_DECL_TEMPLATE_SPECIALIZATION (decl); } else { /* This cannot be an explicit specialization. There are not enough headers for all of the qualifying classes. For example, we might have: template <> void S<int>::T<char>::f(); But, we're missing another template <>. */ cp_error("too few template parameter lists in declaration of `%D'", decl); return decl; } } else if (processing_explicit_instantiation) { if (template_header_count) cp_error ("template parameter list used in explicit instantiation"); if (have_def) cp_error ("definition provided for explicit instantiation"); explicit_instantiation = 1; } else if (ctype != NULL_TREE && !TYPE_BEING_DEFINED (ctype) && CLASSTYPE_TEMPLATE_INSTANTIATION (ctype) && !is_friend) { /* This case catches outdated code that looks like this: template <class T> struct S { void f(); }; void S<int>::f() {} // Missing template <> We disable this check when the type is being defined to avoid complaining about default compiler-generated constructors, destructors, and assignment operators. Since the type is an instantiation, not a specialization, these are the only functions that can be defined before the class is complete. */ /* If they said template <class T> void S<int>::f() {} that's bogus. */ if (template_header_count) { cp_error ("template parameters specified in specialization"); return decl; } if (pedantic) cp_pedwarn ("explicit specialization not preceded by `template <>'"); specialization = 1; SET_DECL_TEMPLATE_SPECIALIZATION (decl); } else if (TREE_CODE (declarator) == TEMPLATE_ID_EXPR) { if (is_friend) /* This could be something like: template <class T> void f(T); class S { friend void f<>(int); } */ specialization = 1; else { /* This case handles bogus declarations like template <> template <class T> void f<int>(); */ cp_error ("template-id `%D' in declaration of primary template", declarator); return decl; } } if (specialization || member_specialization) { tree t = TYPE_ARG_TYPES (TREE_TYPE (decl)); for (; t; t = TREE_CHAIN (t)) if (TREE_PURPOSE (t)) { cp_pedwarn ("default argument specified in explicit specialization"); break; } } if (specialization || member_specialization || explicit_instantiation) { tree gen_tmpl; tree tmpl = NULL_TREE; tree targs = NULL_TREE; /* Make sure that the declarator is a TEMPLATE_ID_EXPR. */ if (TREE_CODE (declarator) != TEMPLATE_ID_EXPR) { tree fns; my_friendly_assert (TREE_CODE (declarator) == IDENTIFIER_NODE, 0); if (!ctype) fns = IDENTIFIER_NAMESPACE_VALUE (dname); else fns = dname; declarator = lookup_template_function (fns, NULL_TREE); } if (declarator == error_mark_node) return error_mark_node; if (TREE_CODE (TREE_OPERAND (declarator, 0)) == LOOKUP_EXPR) { /* A friend declaration. We can't do much, because we don't know what this resolves to, yet. */ my_friendly_assert (is_friend != 0, 0); my_friendly_assert (!explicit_instantiation, 0); SET_DECL_IMPLICIT_INSTANTIATION (decl); return decl; } if (ctype != NULL_TREE && TYPE_BEING_DEFINED (ctype)) { if (!explicit_instantiation) /* A specialization in class scope. This is illegal, but the error will already have been flagged by check_specialization_scope. */ return error_mark_node; else { /* It's not legal to write an explicit instantiation in class scope, e.g.: class C { template void f(); } This case is caught by the parser. However, on something like: template class C { void f(); }; (which is illegal) we can get here. The error will be issued later. */ ; } return decl; } else if (ctype != NULL_TREE && (TREE_CODE (TREE_OPERAND (declarator, 0)) == IDENTIFIER_NODE)) { /* Find the list of functions in ctype that have the same name as the declared function. */ tree name = TREE_OPERAND (declarator, 0); tree fns; if (name == constructor_name (ctype) || name == constructor_name_full (ctype)) { int is_constructor = DECL_CONSTRUCTOR_P (decl); if (is_constructor ? !TYPE_HAS_CONSTRUCTOR (ctype) : !TYPE_HAS_DESTRUCTOR (ctype)) { /* From [temp.expl.spec]: If such an explicit specialization for the member of a class template names an implicitly-declared special member function (clause _special_), the program is ill-formed. Similar language is found in [temp.explicit]. */ cp_error ("specialization of implicitly-declared special member function"); return decl; } name = is_constructor ? ctor_identifier : dtor_identifier; } fns = lookup_fnfields (TYPE_BINFO (ctype), name, 1); if (fns == NULL_TREE) { cp_error ("no member function `%s' declared in `%T'", IDENTIFIER_POINTER (name), ctype); return decl; } else TREE_OPERAND (declarator, 0) = fns; } /* Figure out what exactly is being specialized at this point. Note that for an explicit instantiation, even one for a member function, we cannot tell apriori whether the instantiation is for a member template, or just a member function of a template class. Even if a member template is being instantiated, the member template arguments may be elided if they can be deduced from the rest of the declaration. */ tmpl = determine_specialization (declarator, decl, &targs, member_specialization, 1); if (tmpl && tmpl != error_mark_node) { gen_tmpl = most_general_template (tmpl); if (explicit_instantiation) { /* We don't set DECL_EXPLICIT_INSTANTIATION here; that is done by do_decl_instantiation later. */ decl = instantiate_template (tmpl, innermost_args (targs)); return decl; } /* If we though that the DECL was a member function, but it turns out to be specializing a static member function, make DECL a static member function as well. */ if (DECL_STATIC_FUNCTION_P (tmpl) && DECL_NONSTATIC_MEMBER_FUNCTION_P (decl)) { revert_static_member_fn (&decl, 0, 0); last_function_parms = TREE_CHAIN (last_function_parms); } /* Set up the DECL_TEMPLATE_INFO for DECL. */ DECL_TEMPLATE_INFO (decl) = perm_tree_cons (tmpl, targs, NULL_TREE); /* Mangle the function name appropriately. Note that we do not mangle specializations of non-template member functions of template classes, e.g. with template <class T> struct S { void f(); } and given the specialization template <> void S<int>::f() {} we do not mangle S<int>::f() here. That's because it's just an ordinary member function and doesn't need special treatment. We do this here so that the ordinary, non-template, name-mangling algorith will not be used later. */ if ((is_member_template (tmpl) || ctype == NULL_TREE) && name_mangling_version >= 1) set_mangled_name_for_template_decl (decl); if (is_friend && !have_def) /* This is not really a declaration of a specialization. It's just the name of an instantiation. But, it's not a request for an instantiation, either. */ SET_DECL_IMPLICIT_INSTANTIATION (decl); /* Register this specialization so that we can find it again. */ decl = register_specialization (decl, gen_tmpl, targs); return decl; } } return decl; } /* TYPE is being declared. Verify that the use of template headers and such is reasonable. Issue error messages if not. */ void maybe_check_template_type (type) tree type; { if (template_header_count) { /* We are in the scope of some `template <...>' header. */ int context_depth = template_class_depth_real (TYPE_CONTEXT (type), /*count_specializations=*/1); if (template_header_count <= context_depth) /* This is OK; the template headers are for the context. We are actually too lenient here; like check_explicit_specialization we should consider the number of template types included in the actual declaration. For example, template <class T> struct S { template <class U> template <class V> struct I {}; }; is illegal, but: template <class T> struct S { template <class U> struct I; }; template <class T> template <class U. struct S<T>::I {}; is not. */ ; else if (template_header_count > context_depth + 1) /* There are two many template parameter lists. */ cp_error ("too many template parameter lists in declaration of `%T'", type); } } /* Returns 1 iff PARMS1 and PARMS2 are identical sets of template parameters. These are represented in the same format used for DECL_TEMPLATE_PARMS. */ int comp_template_parms (parms1, parms2) tree parms1; tree parms2; { tree p1; tree p2; if (parms1 == parms2) return 1; for (p1 = parms1, p2 = parms2; p1 != NULL_TREE && p2 != NULL_TREE; p1 = TREE_CHAIN (p1), p2 = TREE_CHAIN (p2)) { tree t1 = TREE_VALUE (p1); tree t2 = TREE_VALUE (p2); int i; my_friendly_assert (TREE_CODE (t1) == TREE_VEC, 0); my_friendly_assert (TREE_CODE (t2) == TREE_VEC, 0); if (TREE_VEC_LENGTH (t1) != TREE_VEC_LENGTH (t2)) return 0; for (i = 0; i < TREE_VEC_LENGTH (t2); ++i) { tree parm1 = TREE_VALUE (TREE_VEC_ELT (t1, i)); tree parm2 = TREE_VALUE (TREE_VEC_ELT (t2, i)); if (TREE_CODE (parm1) != TREE_CODE (parm2)) return 0; if (TREE_CODE (parm1) == TEMPLATE_TYPE_PARM) continue; else if (!same_type_p (TREE_TYPE (parm1), TREE_TYPE (parm2))) return 0; } } if ((p1 != NULL_TREE) != (p2 != NULL_TREE)) /* One set of parameters has more parameters lists than the other. */ return 0; return 1; } /* Returns 1 iff old_id is a template parameter. OLD_DECL is the decl from IDENTIFIER_LOCAL_VALUE (new identifier). */ int decl_template_parm_p (old_decl) tree old_decl; { /* For template template parms. */ if (TREE_CODE (old_decl) == TEMPLATE_DECL && TREE_TYPE (old_decl) && TREE_CODE (TREE_TYPE (old_decl)) == TEMPLATE_TEMPLATE_PARM) return 1; /* For template type parms. */ if (TREE_CODE (old_decl) == TYPE_DECL && TREE_TYPE (old_decl) && TREE_CODE (TREE_TYPE (old_decl)) == TEMPLATE_TYPE_PARM) return 1; /* For template non-type parms. */ if (TREE_CODE (old_decl) == CONST_DECL && DECL_INITIAL (old_decl) && TREE_CODE (DECL_INITIAL (old_decl)) == TEMPLATE_PARM_INDEX) return 1; return 0; } /* Return a new TEMPLATE_PARM_INDEX with the indicated INDEX, LEVEL, ORIG_LEVEL, DECL, and TYPE. */ static tree build_template_parm_index (index, level, orig_level, decl, type) int index; int level; int orig_level; tree decl; tree type; { tree t = make_node (TEMPLATE_PARM_INDEX); TEMPLATE_PARM_IDX (t) = index; TEMPLATE_PARM_LEVEL (t) = level; TEMPLATE_PARM_ORIG_LEVEL (t) = orig_level; TEMPLATE_PARM_DECL (t) = decl; TREE_TYPE (t) = type; return t; } /* Return a TEMPLATE_PARM_INDEX, similar to INDEX, but whose TEMPLATE_PARM_LEVEL has been decreased by LEVELS. If such a TEMPLATE_PARM_INDEX already exists, it is returned; otherwise, a new one is created. */ static tree reduce_template_parm_level (index, type, levels) tree index; tree type; int levels; { if (TEMPLATE_PARM_DESCENDANTS (index) == NULL_TREE || (TEMPLATE_PARM_LEVEL (TEMPLATE_PARM_DESCENDANTS (index)) != TEMPLATE_PARM_LEVEL (index) - levels)) { tree decl = build_decl (TREE_CODE (TEMPLATE_PARM_DECL (index)), DECL_NAME (TEMPLATE_PARM_DECL (index)), type); tree t = build_template_parm_index (TEMPLATE_PARM_IDX (index), TEMPLATE_PARM_LEVEL (index) - levels, TEMPLATE_PARM_ORIG_LEVEL (index), decl, type); TEMPLATE_PARM_DESCENDANTS (index) = t; /* Template template parameters need this. */ DECL_TEMPLATE_PARMS (decl) = DECL_TEMPLATE_PARMS (TEMPLATE_PARM_DECL (index)); } return TEMPLATE_PARM_DESCENDANTS (index); } /* Process information from new template parameter NEXT and append it to the LIST being built. */ tree process_template_parm (list, next) tree list, next; { tree parm; tree decl = 0; tree defval; int is_type, idx; parm = next; my_friendly_assert (TREE_CODE (parm) == TREE_LIST, 259); defval = TREE_PURPOSE (parm); parm = TREE_VALUE (parm); is_type = TREE_PURPOSE (parm) == class_type_node; if (list) { tree p = TREE_VALUE (tree_last (list)); if (TREE_CODE (p) == TYPE_DECL) idx = TEMPLATE_TYPE_IDX (TREE_TYPE (p)); else if (TREE_CODE (p) == TEMPLATE_DECL) idx = TEMPLATE_TYPE_IDX (TREE_TYPE (DECL_TEMPLATE_RESULT (p))); else idx = TEMPLATE_PARM_IDX (DECL_INITIAL (p)); ++idx; } else idx = 0; if (!is_type) { my_friendly_assert (TREE_CODE (TREE_PURPOSE (parm)) == TREE_LIST, 260); /* is a const-param */ parm = grokdeclarator (TREE_VALUE (parm), TREE_PURPOSE (parm), PARM, 0, NULL_TREE); /* A template parameter is not modifiable. */ TREE_READONLY (parm) = 1; if (IS_AGGR_TYPE (TREE_TYPE (parm)) && TREE_CODE (TREE_TYPE (parm)) != TEMPLATE_TYPE_PARM && TREE_CODE (TREE_TYPE (parm)) != TYPENAME_TYPE) { cp_error ("`%#T' is not a valid type for a template constant parameter", TREE_TYPE (parm)); if (DECL_NAME (parm) == NULL_TREE) error (" a template type parameter must begin with `class' or `typename'"); TREE_TYPE (parm) = void_type_node; } else if (pedantic && (TREE_CODE (TREE_TYPE (parm)) == REAL_TYPE || TREE_CODE (TREE_TYPE (parm)) == COMPLEX_TYPE)) cp_pedwarn ("`%T' is not a valid type for a template constant parameter", TREE_TYPE (parm)); if (TREE_PERMANENT (parm) == 0) { parm = copy_node (parm); TREE_PERMANENT (parm) = 1; } decl = build_decl (CONST_DECL, DECL_NAME (parm), TREE_TYPE (parm)); DECL_INITIAL (parm) = DECL_INITIAL (decl) = build_template_parm_index (idx, processing_template_decl, processing_template_decl, decl, TREE_TYPE (parm)); } else { tree t; parm = TREE_VALUE (parm); if (parm && TREE_CODE (parm) == TEMPLATE_DECL) { t = make_lang_type (TEMPLATE_TEMPLATE_PARM); /* This is for distinguishing between real templates and template template parameters */ TREE_TYPE (parm) = t; TREE_TYPE (DECL_TEMPLATE_RESULT (parm)) = t; decl = parm; } else { t = make_lang_type (TEMPLATE_TYPE_PARM); /* parm is either IDENTIFIER_NODE or NULL_TREE */ decl = build_decl (TYPE_DECL, parm, t); } TYPE_NAME (t) = decl; TYPE_STUB_DECL (t) = decl; parm = decl; TEMPLATE_TYPE_PARM_INDEX (t) = build_template_parm_index (idx, processing_template_decl, processing_template_decl, decl, TREE_TYPE (parm)); } SET_DECL_ARTIFICIAL (decl); pushdecl (decl); parm = build_tree_list (defval, parm); return chainon (list, parm); } /* The end of a template parameter list has been reached. Process the tree list into a parameter vector, converting each parameter into a more useful form. Type parameters are saved as IDENTIFIER_NODEs, and others as PARM_DECLs. */ tree end_template_parm_list (parms) tree parms; { int nparms; tree parm; tree saved_parmlist = make_tree_vec (list_length (parms)); current_template_parms = tree_cons (build_int_2 (0, processing_template_decl), saved_parmlist, current_template_parms); for (parm = parms, nparms = 0; parm; parm = TREE_CHAIN (parm), nparms++) TREE_VEC_ELT (saved_parmlist, nparms) = parm; --processing_template_parmlist; return saved_parmlist; } /* end_template_decl is called after a template declaration is seen. */ void end_template_decl () { reset_specialization (); if (! processing_template_decl) return; /* This matches the pushlevel in begin_template_parm_list. */ poplevel (0, 0, 0); --processing_template_decl; current_template_parms = TREE_CHAIN (current_template_parms); (void) get_pending_sizes (); /* Why? */ } /* Given a template argument vector containing the template PARMS. The innermost PARMS are given first. */ tree current_template_args () { tree header; tree args = NULL_TREE; int length = TMPL_PARMS_DEPTH (current_template_parms); int l = length; /* If there is only one level of template parameters, we do not create a TREE_VEC of TREE_VECs. Instead, we return a single TREE_VEC containing the arguments. */ if (length > 1) args = make_tree_vec (length); for (header = current_template_parms; header; header = TREE_CHAIN (header)) { tree a = copy_node (TREE_VALUE (header)); int i; TREE_TYPE (a) = NULL_TREE; for (i = TREE_VEC_LENGTH (a) - 1; i >= 0; --i) { tree t = TREE_VEC_ELT (a, i); /* T will be a list if we are called from within a begin/end_template_parm_list pair, but a vector directly if within a begin/end_member_template_processing pair. */ if (TREE_CODE (t) == TREE_LIST) { t = TREE_VALUE (t); if (TREE_CODE (t) == TYPE_DECL || TREE_CODE (t) == TEMPLATE_DECL) t = TREE_TYPE (t); else t = DECL_INITIAL (t); TREE_VEC_ELT (a, i) = t; } } if (length > 1) TREE_VEC_ELT (args, --l) = a; else args = a; } return args; } /* Return a TEMPLATE_DECL corresponding to DECL, using the indicated template PARMS. Used by push_template_decl below. */ static tree build_template_decl (decl, parms) tree decl; tree parms; { tree tmpl = build_lang_decl (TEMPLATE_DECL, DECL_NAME (decl), NULL_TREE); DECL_TEMPLATE_PARMS (tmpl) = parms; DECL_CONTEXT (tmpl) = DECL_CONTEXT (decl); if (DECL_LANG_SPECIFIC (decl)) { DECL_CLASS_CONTEXT (tmpl) = DECL_CLASS_CONTEXT (decl); DECL_STATIC_FUNCTION_P (tmpl) = DECL_STATIC_FUNCTION_P (decl); } return tmpl; } struct template_parm_data { /* The level of the template parameters we are currently processing. */ int level; /* The index of the specialization argument we are currently processing. */ int current_arg; /* An array whose size is the number of template parameters. The elements are non-zero if the parameter has been used in any one of the arguments processed so far. */ int* parms; /* An array whose size is the number of template arguments. The elements are non-zero if the argument makes use of template parameters of this level. */ int* arg_uses_template_parms; }; /* Subroutine of push_template_decl used to see if each template parameter in a partial specialization is used in the explicit argument list. If T is of the LEVEL given in DATA (which is treated as a template_parm_data*), then DATA->PARMS is marked appropriately. */ static int mark_template_parm (t, data) tree t; void* data; { int level; int idx; struct template_parm_data* tpd = (struct template_parm_data*) data; if (TREE_CODE (t) == TEMPLATE_PARM_INDEX) { level = TEMPLATE_PARM_LEVEL (t); idx = TEMPLATE_PARM_IDX (t); } else { level = TEMPLATE_TYPE_LEVEL (t); idx = TEMPLATE_TYPE_IDX (t); } if (level == tpd->level) { tpd->parms[idx] = 1; tpd->arg_uses_template_parms[tpd->current_arg] = 1; } /* Return zero so that for_each_template_parm will continue the traversal of the tree; we want to mark *every* template parm. */ return 0; } /* Process the partial specialization DECL. */ tree process_partial_specialization (decl) tree decl; { tree type = TREE_TYPE (decl); tree maintmpl = CLASSTYPE_TI_TEMPLATE (type); tree specargs = CLASSTYPE_TI_ARGS (type); tree inner_args = innermost_args (specargs); tree inner_parms = INNERMOST_TEMPLATE_PARMS (current_template_parms); tree main_inner_parms = DECL_INNERMOST_TEMPLATE_PARMS (maintmpl); int nargs = TREE_VEC_LENGTH (inner_args); int ntparms = TREE_VEC_LENGTH (inner_parms); int i; int did_error_intro = 0; struct template_parm_data tpd; struct template_parm_data tpd2; /* We check that each of the template parameters given in the partial specialization is used in the argument list to the specialization. For example: template <class T> struct S; template <class T> struct S<T*>; The second declaration is OK because `T*' uses the template parameter T, whereas template <class T> struct S<int>; is no good. Even trickier is: template <class T> struct S1 { template <class U> struct S2; template <class U> struct S2<T>; }; The S2<T> declaration is actually illegal; it is a full-specialization. Of course, template <class U> struct S2<T (*)(U)>; or some such would have been OK. */ tpd.level = TMPL_PARMS_DEPTH (current_template_parms); tpd.parms = alloca (sizeof (int) * ntparms); bzero ((PTR) tpd.parms, sizeof (int) * ntparms); tpd.arg_uses_template_parms = alloca (sizeof (int) * nargs); bzero ((PTR) tpd.arg_uses_template_parms, sizeof (int) * nargs); for (i = 0; i < nargs; ++i) { tpd.current_arg = i; for_each_template_parm (TREE_VEC_ELT (inner_args, i), &mark_template_parm, &tpd); } for (i = 0; i < ntparms; ++i) if (tpd.parms[i] == 0) { /* One of the template parms was not used in the specialization. */ if (!did_error_intro) { cp_error ("template parameters not used in partial specialization:"); did_error_intro = 1; } cp_error (" `%D'", TREE_VALUE (TREE_VEC_ELT (inner_parms, i))); } /* [temp.class.spec] The argument list of the specialization shall not be identical to the implicit argument list of the primary template. */ if (comp_template_args (inner_args, innermost_args (CLASSTYPE_TI_ARGS (TREE_TYPE (maintmpl))))) cp_error ("partial specialization `%T' does not specialize any template arguments", type); /* [temp.class.spec] A partially specialized non-type argument expression shall not involve template parameters of the partial specialization except when the argument expression is a simple identifier. The type of a template parameter corresponding to a specialized non-type argument shall not be dependent on a parameter of the specialization. */ my_friendly_assert (nargs == DECL_NTPARMS (maintmpl), 0); tpd2.parms = 0; for (i = 0; i < nargs; ++i) { tree arg = TREE_VEC_ELT (inner_args, i); if (/* These first two lines are the `non-type' bit. */ TREE_CODE_CLASS (TREE_CODE (arg)) != 't' && TREE_CODE (arg) != TEMPLATE_DECL /* This next line is the `argument expression is not just a simple identifier' condition and also the `specialized non-type argument' bit. */ && TREE_CODE (arg) != TEMPLATE_PARM_INDEX) { if (tpd.arg_uses_template_parms[i]) cp_error ("template argument `%E' involves template parameter(s)", arg); else { /* Look at the corresponding template parameter, marking which template parameters its type depends upon. */ tree type = TREE_TYPE (TREE_VALUE (TREE_VEC_ELT (main_inner_parms, i))); if (!tpd2.parms) { /* We haven't yet initialized TPD2. Do so now. */ tpd2.arg_uses_template_parms = (int*) alloca (sizeof (int) * nargs); /* The number of paramters here is the number in the main template, which, as checked in the assertion above, is NARGS. */ tpd2.parms = (int*) alloca (sizeof (int) * nargs); tpd2.level = TMPL_PARMS_DEPTH (DECL_TEMPLATE_PARMS (maintmpl)); } /* Mark the template paramters. But this time, we're looking for the template parameters of the main template, not in the specialization. */ tpd2.current_arg = i; tpd2.arg_uses_template_parms[i] = 0; bzero ((PTR) tpd2.parms, sizeof (int) * nargs); for_each_template_parm (type, &mark_template_parm, &tpd2); if (tpd2.arg_uses_template_parms [i]) { /* The type depended on some template parameters. If they are fully specialized in the specialization, that's OK. */ int j; for (j = 0; j < nargs; ++j) if (tpd2.parms[j] != 0 && tpd.arg_uses_template_parms [j]) { cp_error ("type `%T' of template argument `%E' depends on template paramter(s)", type, arg); break; } } } } } if (retrieve_specialization (maintmpl, specargs)) /* We've already got this specialization. */ return decl; DECL_TEMPLATE_SPECIALIZATIONS (maintmpl) = CLASSTYPE_TI_SPEC_INFO (type) = perm_tree_cons (inner_args, inner_parms, DECL_TEMPLATE_SPECIALIZATIONS (maintmpl)); TREE_TYPE (DECL_TEMPLATE_SPECIALIZATIONS (maintmpl)) = type; return decl; } /* Check that a template declaration's use of default arguments is not invalid. Here, PARMS are the template parameters. IS_PRIMARY is non-zero if DECL is the thing declared by a primary template. IS_PARTIAL is non-zero if DECL is a partial specialization. */ static void check_default_tmpl_args (decl, parms, is_primary, is_partial) tree decl; tree parms; int is_primary; int is_partial; { char* msg; int last_level_to_check; /* [temp.param] A default template-argument shall not be specified in a function template declaration or a function template definition, nor in the template-parameter-list of the definition of a member of a class template. */ if (current_class_type && !TYPE_BEING_DEFINED (current_class_type) && DECL_REAL_CONTEXT (decl) == current_class_type && DECL_DEFINED_IN_CLASS_P (decl)) /* We already checked these parameters when the template was declared, so there's no need to do it again now. This is an inline member function definition. */ return; if (TREE_CODE (decl) != TYPE_DECL || is_partial || !is_primary) /* For an ordinary class template, default template arguments are allowed at the innermost level, e.g.: template <class T = int> struct S {}; but, in a partial specialization, they're not allowed even there, as we have in [temp.class.spec]: The template parameter list of a specialization shall not contain default template argument values. So, for a partial specialization, or for a function template, we look at all of them. */ ; else /* But, for a primary class template that is not a partial specialization we look at all template parameters except the innermost ones. */ parms = TREE_CHAIN (parms); /* Figure out what error message to issue. */ if (TREE_CODE (decl) == FUNCTION_DECL) msg = "default argument for template parameter in function template `%D'"; else if (is_partial) msg = "default argument in partial specialization `%D'"; else msg = "default argument for template parameter for class enclosing `%D'"; if (current_class_type && TYPE_BEING_DEFINED (current_class_type)) /* If we're inside a class definition, there's no need to examine the paramters to the class itself. On the one hand, they will be checked when the class is defined, and, on the other, default arguments are legal in things like: template <class T = double> struct S { template <class U> void f(U); }; Here the default argument for `S' has no bearing on the declaration of `f'. */ last_level_to_check = template_class_depth (current_class_type) + 1; else /* Check everything. */ last_level_to_check = 0; for (; parms && TMPL_PARMS_DEPTH (parms) >= last_level_to_check; parms = TREE_CHAIN (parms)) { tree inner_parms = TREE_VALUE (parms); int i, ntparms; ntparms = TREE_VEC_LENGTH (inner_parms); for (i = 0; i < ntparms; ++i) if (TREE_PURPOSE (TREE_VEC_ELT (inner_parms, i))) { if (msg) { cp_error (msg, decl); msg = 0; } /* Clear out the default argument so that we are not confused later. */ TREE_PURPOSE (TREE_VEC_ELT (inner_parms, i)) = NULL_TREE; } /* At this point, if we're still interested in issuing messages, they must apply to classes surrounding the object declared. */ if (msg) msg = "default argument for template parameter for class enclosing `%D'"; } } /* Creates a TEMPLATE_DECL for the indicated DECL using the template parameters given by current_template_args, or reuses a previously existing one, if appropriate. Returns the DECL, or an equivalent one, if it is replaced via a call to duplicate_decls. If IS_FRIEND is non-zero, DECL is a friend declaration. */ tree push_template_decl_real (decl, is_friend) tree decl; int is_friend; { tree tmpl; tree args; tree info; tree ctx; int primary; int is_partial; /* See if this is a partial specialization. */ is_partial = (TREE_CODE (decl) == TYPE_DECL && DECL_ARTIFICIAL (decl) && TREE_CODE (TREE_TYPE (decl)) != ENUMERAL_TYPE && CLASSTYPE_TEMPLATE_SPECIALIZATION (TREE_TYPE (decl))); is_friend |= (TREE_CODE (decl) == FUNCTION_DECL && DECL_FRIEND_P (decl)); if (is_friend) /* For a friend, we want the context of the friend function, not the type of which it is a friend. */ ctx = DECL_CONTEXT (decl); else if (DECL_REAL_CONTEXT (decl) && TREE_CODE (DECL_REAL_CONTEXT (decl)) != NAMESPACE_DECL) /* In the case of a virtual function, we want the class in which it is defined. */ ctx = DECL_REAL_CONTEXT (decl); else /* Otherwise, if we're currently definining some class, the DECL is assumed to be a member of the class. */ ctx = current_class_type; if (ctx && TREE_CODE (ctx) == NAMESPACE_DECL) ctx = NULL_TREE; if (!DECL_CONTEXT (decl)) DECL_CONTEXT (decl) = FROB_CONTEXT (current_namespace); /* For determining whether this is a primary template or not, we're really interested in the lexical context, not the true context. */ if (is_friend) info = current_class_type; else info = ctx; /* See if this is a primary template. */ if (info && TREE_CODE (info) == FUNCTION_DECL) primary = 0; /* Note that template_class_depth returns 0 if given NULL_TREE, so this next line works even when we are at global scope. */ else if (processing_template_decl > template_class_depth (info)) primary = 1; else primary = 0; if (primary) { if (current_lang_name == lang_name_c) cp_error ("template with C linkage"); if (TREE_CODE (decl) == TYPE_DECL && ANON_AGGRNAME_P (DECL_NAME (decl))) cp_error ("template class without a name"); if (TREE_CODE (decl) == TYPE_DECL && TREE_CODE (TREE_TYPE (decl)) == ENUMERAL_TYPE) cp_error ("template declaration of `%#T'", TREE_TYPE (decl)); } /* Check to see that the rules regarding the use of default arguments are not being violated. */ check_default_tmpl_args (decl, current_template_parms, primary, is_partial); if (is_partial) return process_partial_specialization (decl); args = current_template_args (); if (!ctx || TREE_CODE (ctx) == FUNCTION_DECL || TYPE_BEING_DEFINED (ctx) || (is_friend && !DECL_TEMPLATE_INFO (decl))) { if (DECL_LANG_SPECIFIC (decl) && DECL_TEMPLATE_INFO (decl) && DECL_TI_TEMPLATE (decl)) tmpl = DECL_TI_TEMPLATE (decl); else { tmpl = build_template_decl (decl, current_template_parms); if (DECL_LANG_SPECIFIC (decl) && DECL_TEMPLATE_SPECIALIZATION (decl)) { /* A specialization of a member template of a template class. */ SET_DECL_TEMPLATE_SPECIALIZATION (tmpl); DECL_TEMPLATE_INFO (tmpl) = DECL_TEMPLATE_INFO (decl); DECL_TEMPLATE_INFO (decl) = NULL_TREE; } } } else { tree a, t, current, parms; int i; if (CLASSTYPE_TEMPLATE_INSTANTIATION (ctx)) cp_error ("must specialize `%#T' before defining member `%#D'", ctx, decl); if (TREE_CODE (decl) == TYPE_DECL) { if ((IS_AGGR_TYPE_CODE (TREE_CODE (TREE_TYPE (decl))) || TREE_CODE (TREE_TYPE (decl)) == ENUMERAL_TYPE) && TYPE_TEMPLATE_INFO (TREE_TYPE (decl)) && TYPE_TI_TEMPLATE (TREE_TYPE (decl))) tmpl = TYPE_TI_TEMPLATE (TREE_TYPE (decl)); else { cp_error ("`%D' does not declare a template type", decl); return decl; } } else if (! DECL_TEMPLATE_INFO (decl)) { cp_error ("template definition of non-template `%#D'", decl); return decl; } else tmpl = DECL_TI_TEMPLATE (decl); if (is_member_template (tmpl) && DECL_FUNCTION_TEMPLATE_P (tmpl) && DECL_TEMPLATE_INFO (decl) && DECL_TI_ARGS (decl) && DECL_TEMPLATE_SPECIALIZATION (decl)) { tree new_tmpl; /* The declaration is a specialization of a member template, declared outside the class. Therefore, the innermost template arguments will be NULL, so we replace them with the arguments determined by the earlier call to check_explicit_specialization. */ args = DECL_TI_ARGS (decl); new_tmpl = build_template_decl (decl, current_template_parms); DECL_TEMPLATE_RESULT (new_tmpl) = decl; TREE_TYPE (new_tmpl) = TREE_TYPE (decl); DECL_TI_TEMPLATE (decl) = new_tmpl; SET_DECL_TEMPLATE_SPECIALIZATION (new_tmpl); DECL_TEMPLATE_INFO (new_tmpl) = perm_tree_cons (tmpl, args, NULL_TREE); register_specialization (new_tmpl, tmpl, args); return decl; } /* Make sure the template headers we got make sense. */ parms = DECL_TEMPLATE_PARMS (tmpl); i = TMPL_PARMS_DEPTH (parms); if (TMPL_ARGS_DEPTH (args) != i) { cp_error ("expected %d levels of template parms for `%#D', got %d", i, decl, TMPL_ARGS_DEPTH (args)); } else for (current = decl; i > 0; --i, parms = TREE_CHAIN (parms)) { a = TMPL_ARGS_LEVEL (args, i); t = INNERMOST_TEMPLATE_PARMS (parms); if (TREE_VEC_LENGTH (t) != TREE_VEC_LENGTH (a)) { if (current == decl) cp_error ("got %d template parameters for `%#D'", TREE_VEC_LENGTH (a), decl); else cp_error ("got %d template parameters for `%#T'", TREE_VEC_LENGTH (a), current); cp_error (" but %d required", TREE_VEC_LENGTH (t)); } /* Perhaps we should also check that the parms are used in the appropriate qualifying scopes in the declarator? */ if (current == decl) current = ctx; else current = TYPE_CONTEXT (current); } } DECL_TEMPLATE_RESULT (tmpl) = decl; TREE_TYPE (tmpl) = TREE_TYPE (decl); /* Push template declarations for global functions and types. Note that we do not try to push a global template friend declared in a template class; such a thing may well depend on the template parameters of the class. */ if (! ctx && !(is_friend && template_class_depth (current_class_type) > 0)) tmpl = pushdecl_namespace_level (tmpl); if (primary) DECL_PRIMARY_TEMPLATE (tmpl) = tmpl; info = perm_tree_cons (tmpl, args, NULL_TREE); if (TREE_CODE (decl) == TYPE_DECL && DECL_ARTIFICIAL (decl)) { SET_TYPE_TEMPLATE_INFO (TREE_TYPE (tmpl), info); if ((!ctx || TREE_CODE (ctx) != FUNCTION_DECL) && TREE_CODE (TREE_TYPE (decl)) != ENUMERAL_TYPE) DECL_NAME (decl) = classtype_mangled_name (TREE_TYPE (decl)); } else if (! DECL_LANG_SPECIFIC (decl)) cp_error ("template declaration of `%#D'", decl); else DECL_TEMPLATE_INFO (decl) = info; return DECL_TEMPLATE_RESULT (tmpl); } tree push_template_decl (decl) tree decl; { return push_template_decl_real (decl, 0); } /* Called when a class template TYPE is redeclared with the indicated template PARMS, e.g.: template <class T> struct S; template <class T> struct S {}; */ void redeclare_class_template (type, parms) tree type; tree parms; { tree tmpl = CLASSTYPE_TI_TEMPLATE (type); tree tmpl_parms; int i; if (!PRIMARY_TEMPLATE_P (tmpl)) /* The type is nested in some template class. Nothing to worry about here; there are no new template parameters for the nested type. */ return; parms = INNERMOST_TEMPLATE_PARMS (parms); tmpl_parms = DECL_INNERMOST_TEMPLATE_PARMS (tmpl); if (TREE_VEC_LENGTH (parms) != TREE_VEC_LENGTH (tmpl_parms)) { cp_error_at ("previous declaration `%D'", tmpl); cp_error ("used %d template parameter%s instead of %d", TREE_VEC_LENGTH (tmpl_parms), TREE_VEC_LENGTH (tmpl_parms) == 1 ? "" : "s", TREE_VEC_LENGTH (parms)); return; } for (i = 0; i < TREE_VEC_LENGTH (tmpl_parms); ++i) { tree tmpl_parm = TREE_VALUE (TREE_VEC_ELT (tmpl_parms, i)); tree parm = TREE_VALUE (TREE_VEC_ELT (parms, i)); tree tmpl_default = TREE_PURPOSE (TREE_VEC_ELT (tmpl_parms, i)); tree parm_default = TREE_PURPOSE (TREE_VEC_ELT (parms, i)); if (TREE_CODE (tmpl_parm) != TREE_CODE (parm)) { cp_error_at ("template parameter `%#D'", tmpl_parm); cp_error ("redeclared here as `%#D'", parm); return; } if (tmpl_default != NULL_TREE && parm_default != NULL_TREE) { /* We have in [temp.param]: A template-parameter may not be given default arguments by two different declarations in the same scope. */ cp_error ("redefinition of default argument for `%#D'", parm); cp_error_at (" original definition appeared here", tmpl_parm); return; } if (parm_default != NULL_TREE) /* Update the previous template parameters (which are the ones that will really count) with the new default value. */ TREE_PURPOSE (TREE_VEC_ELT (tmpl_parms, i)) = parm_default; } } /* Attempt to convert the non-type template parameter EXPR to the indicated TYPE. If the conversion is successful, return the converted value. If the conversion is unsuccesful, return NULL_TREE if we issued an error message, or error_mark_node if we did not. We issue error messages for out-and-out bad template parameters, but not simply because the conversion failed, since we might be just trying to do argument deduction. By the time this function is called, neither TYPE nor EXPR may make use of template parameters. */ static tree convert_nontype_argument (type, expr) tree type; tree expr; { tree expr_type = TREE_TYPE (expr); /* A template-argument for a non-type, non-template template-parameter shall be one of: --an integral constant-expression of integral or enumeration type; or --the name of a non-type template-parameter; or --the name of an object or function with external linkage, including function templates and function template-ids but excluding non-static class members, expressed as id-expression; or --the address of an object or function with external linkage, including function templates and function template-ids but excluding non-static class members, expressed as & id-expression where the & is optional if the name refers to a function or array; or --a pointer to member expressed as described in _expr.unary.op_. */ /* An integral constant-expression can include const variables or enumerators. */ if (INTEGRAL_TYPE_P (expr_type) && TREE_READONLY_DECL_P (expr)) expr = decl_constant_value (expr); if (is_overloaded_fn (expr)) /* OK for now. We'll check that it has external linkage later. Check this first since if expr_type is the unknown_type_node we would otherwise complain below. */ ; else if (INTEGRAL_TYPE_P (expr_type) || TYPE_PTRMEM_P (expr_type) || TYPE_PTRMEMFUNC_P (expr_type) /* The next two are g++ extensions. */ || TREE_CODE (expr_type) == REAL_TYPE || TREE_CODE (expr_type) == COMPLEX_TYPE) { if (! TREE_CONSTANT (expr)) { non_constant: cp_error ("non-constant `%E' cannot be used as template argument", expr); return NULL_TREE; } } else if (TYPE_PTR_P (expr_type) /* If expr is the address of an overloaded function, we will get the unknown_type_node at this point. */ || expr_type == unknown_type_node) { tree referent; tree e = expr; STRIP_NOPS (e); if (TREE_CODE (e) != ADDR_EXPR) { bad_argument: cp_error ("`%E' is not a valid template argument", expr); error ("it must be %s%s with external linkage", TREE_CODE (TREE_TYPE (expr)) == POINTER_TYPE ? "a pointer to " : "", TREE_CODE (TREE_TYPE (TREE_TYPE (expr))) == FUNCTION_TYPE ? "a function" : "an object"); return NULL_TREE; } referent = TREE_OPERAND (e, 0); STRIP_NOPS (referent); if (TREE_CODE (referent) == STRING_CST) { cp_error ("string literal %E is not a valid template argument", referent); error ("because it is the address of an object with static linkage"); return NULL_TREE; } if (is_overloaded_fn (referent)) /* We'll check that it has external linkage later. */ ; else if (TREE_CODE (referent) != VAR_DECL) goto bad_argument; else if (!TREE_PUBLIC (referent)) { cp_error ("address of non-extern `%E' cannot be used as template argument", referent); return error_mark_node; } } else if (TREE_CODE (expr) == VAR_DECL) { if (!TREE_PUBLIC (expr)) goto bad_argument; } else { cp_error ("object `%E' cannot be used as template argument", expr); return NULL_TREE; } switch (TREE_CODE (type)) { case INTEGER_TYPE: case BOOLEAN_TYPE: case ENUMERAL_TYPE: /* For a non-type template-parameter of integral or enumeration type, integral promotions (_conv.prom_) and integral conversions (_conv.integral_) are applied. */ if (!INTEGRAL_TYPE_P (expr_type)) return error_mark_node; /* It's safe to call digest_init in this case; we know we're just converting one integral constant expression to another. */ expr = digest_init (type, expr, (tree*) 0); if (TREE_CODE (expr) != INTEGER_CST) /* Curiously, some TREE_CONSTNAT integral expressions do not simplify to integer constants. For example, `3 % 0', remains a TRUNC_MOD_EXPR. */ goto non_constant; return expr; case REAL_TYPE: case COMPLEX_TYPE: /* These are g++ extensions. */ if (TREE_CODE (expr_type) != TREE_CODE (type)) return error_mark_node; expr = digest_init (type, expr, (tree*) 0); if (TREE_CODE (expr) != REAL_CST) goto non_constant; return expr; case POINTER_TYPE: { tree type_pointed_to = TREE_TYPE (type); if (TYPE_PTRMEM_P (type)) /* For a non-type template-parameter of type pointer to data member, qualification conversions (_conv.qual_) are applied. */ return perform_qualification_conversions (type, expr); else if (TREE_CODE (type_pointed_to) == FUNCTION_TYPE) { /* For a non-type template-parameter of type pointer to function, only the function-to-pointer conversion (_conv.func_) is applied. If the template-argument represents a set of overloaded functions (or a pointer to such), the matching function is selected from the set (_over.over_). */ tree fns; tree fn; if (TREE_CODE (expr) == ADDR_EXPR) fns = TREE_OPERAND (expr, 0); else fns = expr; fn = instantiate_type (type_pointed_to, fns, 0); if (fn == error_mark_node) return error_mark_node; if (!TREE_PUBLIC (fn)) { if (really_overloaded_fn (fns)) return error_mark_node; else goto bad_argument; } expr = build_unary_op (ADDR_EXPR, fn, 0); my_friendly_assert (same_type_p (type, TREE_TYPE (expr)), 0); return expr; } else { /* For a non-type template-parameter of type pointer to object, qualification conversions (_conv.qual_) and the array-to-pointer conversion (_conv.array_) are applied. [Note: In particular, neither the null pointer conversion (_conv.ptr_) nor the derived-to-base conversion (_conv.ptr_) are applied. Although 0 is a valid template-argument for a non-type template-parameter of integral type, it is not a valid template-argument for a non-type template-parameter of pointer type.] The call to decay_conversion performs the array-to-pointer conversion, if appropriate. */ expr = decay_conversion (expr); if (expr == error_mark_node) return error_mark_node; else return perform_qualification_conversions (type, expr); } } break; case REFERENCE_TYPE: { tree type_referred_to = TREE_TYPE (type); if (TREE_CODE (type_referred_to) == FUNCTION_TYPE) { /* For a non-type template-parameter of type reference to function, no conversions apply. If the template-argument represents a set of overloaded functions, the matching function is selected from the set (_over.over_). */ tree fns = expr; tree fn; fn = instantiate_type (type_referred_to, fns, 0); if (fn == error_mark_node) return error_mark_node; if (!TREE_PUBLIC (fn)) { if (really_overloaded_fn (fns)) /* Don't issue an error here; we might get a different function if the overloading had worked out differently. */ return error_mark_node; else goto bad_argument; } my_friendly_assert (same_type_p (type_referred_to, TREE_TYPE (fn)), 0); return fn; } else { /* For a non-type template-parameter of type reference to object, no conversions apply. The type referred to by the reference may be more cv-qualified than the (otherwise identical) type of the template-argument. The template-parameter is bound directly to the template-argument, which must be an lvalue. */ if ((TYPE_MAIN_VARIANT (expr_type) != TYPE_MAIN_VARIANT (type_referred_to)) || !at_least_as_qualified_p (type_referred_to, expr_type) || !real_lvalue_p (expr)) return error_mark_node; else return expr; } } break; case RECORD_TYPE: { tree fns; tree fn; if (!TYPE_PTRMEMFUNC_P (type)) /* This handles templates like template<class T, T t> void f(); when T is substituted with any class. The second template parameter becomes invalid and the template candidate is rejected. */ return error_mark_node; /* For a non-type template-parameter of type pointer to member function, no conversions apply. If the template-argument represents a set of overloaded member functions, the matching member function is selected from the set (_over.over_). */ if (!TYPE_PTRMEMFUNC_P (expr_type) && expr_type != unknown_type_node) return error_mark_node; if (TREE_CODE (expr) == CONSTRUCTOR) { /* A ptr-to-member constant. */ if (!same_type_p (type, expr_type)) return error_mark_node; else return expr; } if (TREE_CODE (expr) != ADDR_EXPR) return error_mark_node; fns = TREE_OPERAND (expr, 0); fn = instantiate_type (TREE_TYPE (TREE_TYPE (type)), fns, 0); if (fn == error_mark_node) return error_mark_node; expr = build_unary_op (ADDR_EXPR, fn, 0); my_friendly_assert (same_type_p (type, TREE_TYPE (expr)), 0); return expr; } break; default: /* All non-type parameters must have one of these types. */ my_friendly_abort (0); break; } return error_mark_node; } /* Return 1 if PARM_PARMS and ARG_PARMS matches using rule for template template parameters. Both PARM_PARMS and ARG_PARMS are vectors of TREE_LIST nodes containing TYPE_DECL, TEMPLATE_DECL or PARM_DECL. ARG_PARMS may contain more parameters than PARM_PARMS. If this is the case, then extra parameters must have default arguments. Consider the example: template <class T, class Allocator = allocator> class vector; template<template <class U> class TT> class C; C<vector> is a valid instantiation. PARM_PARMS for the above code contains a TYPE_DECL (for U), ARG_PARMS contains two TYPE_DECLs (for T and Allocator) and OUTER_ARGS contains the argument that is used to substitute the TT parameter. */ static int coerce_template_template_parms (parm_parms, arg_parms, in_decl, outer_args) tree parm_parms, arg_parms, in_decl, outer_args; { int nparms, nargs, i; tree parm, arg; my_friendly_assert (TREE_CODE (parm_parms) == TREE_VEC, 0); my_friendly_assert (TREE_CODE (arg_parms) == TREE_VEC, 0); nparms = TREE_VEC_LENGTH (parm_parms); nargs = TREE_VEC_LENGTH (arg_parms); /* The rule here is opposite of coerce_template_parms. */ if (nargs < nparms || (nargs > nparms && TREE_PURPOSE (TREE_VEC_ELT (arg_parms, nparms)) == NULL_TREE)) return 0; for (i = 0; i < nparms; ++i) { parm = TREE_VALUE (TREE_VEC_ELT (parm_parms, i)); arg = TREE_VALUE (TREE_VEC_ELT (arg_parms, i)); if (arg == NULL_TREE || arg == error_mark_node || parm == NULL_TREE || parm == error_mark_node) return 0; if (TREE_CODE (arg) != TREE_CODE (parm)) return 0; switch (TREE_CODE (parm)) { case TYPE_DECL: break; case TEMPLATE_DECL: /* We encounter instantiations of templates like template <template <template <class> class> class TT> class C; */ sorry ("nested template template parameter"); return 0; case PARM_DECL: /* The tsubst call is used to handle cases such as template <class T, template <T> class TT> class D; i.e. the parameter list of TT depends on earlier parameters. */ if (!same_type_p (tsubst (TREE_TYPE (parm), outer_args, in_decl), TREE_TYPE (arg))) return 0; break; default: my_friendly_abort (0); } } return 1; } /* Convert the indicated template ARG as necessary to match the indicated template PARM. Returns the converted ARG, or error_mark_node if the conversion was unsuccessful. Error messages are issued if COMPLAIN is non-zero. This conversion is for the Ith parameter in the parameter list. ARGS is the full set of template arguments deduced so far. */ static tree convert_template_argument (parm, arg, args, complain, i, in_decl) tree parm; tree arg; tree args; int complain; int i; tree in_decl; { tree val; tree inner_args; int is_type, requires_type, is_tmpl_type, requires_tmpl_type; inner_args = innermost_args (args); if (TREE_CODE (arg) == TREE_LIST && TREE_TYPE (arg) != NULL_TREE && TREE_CODE (TREE_TYPE (arg)) == OFFSET_TYPE) { /* The template argument was the name of some member function. That's usually illegal, but static members are OK. In any case, grab the underlying fields/functions and issue an error later if required. */ arg = TREE_VALUE (arg); TREE_TYPE (arg) = unknown_type_node; } requires_tmpl_type = TREE_CODE (parm) == TEMPLATE_DECL; requires_type = (TREE_CODE (parm) == TYPE_DECL || requires_tmpl_type); /* Check if it is a class template. If REQUIRES_TMPL_TYPE is true, we also accept implicitly created TYPE_DECL as a valid argument. This is necessary to handle the case where we pass a template name to a template template parameter in a scope where we've derived from in instantiation of that template, so the template name refers to that instantiation. We really ought to handle this better. */ is_tmpl_type = ((TREE_CODE (arg) == TEMPLATE_DECL && TREE_CODE (DECL_TEMPLATE_RESULT (arg)) == TYPE_DECL) || (TREE_CODE (arg) == TEMPLATE_TEMPLATE_PARM && !TEMPLATE_TEMPLATE_PARM_TEMPLATE_INFO (arg)) || (TREE_CODE (arg) == RECORD_TYPE && CLASSTYPE_TEMPLATE_INFO (arg) && TREE_CODE (TYPE_NAME (arg)) == TYPE_DECL && DECL_ARTIFICIAL (TYPE_NAME (arg)) && requires_tmpl_type && is_base_of_enclosing_class (arg, current_class_type))); if (is_tmpl_type && TREE_CODE (arg) == TEMPLATE_TEMPLATE_PARM) arg = TYPE_STUB_DECL (arg); else if (is_tmpl_type && TREE_CODE (arg) == RECORD_TYPE) arg = CLASSTYPE_TI_TEMPLATE (arg); is_type = TREE_CODE_CLASS (TREE_CODE (arg)) == 't' || is_tmpl_type; if (requires_type && ! is_type && TREE_CODE (arg) == SCOPE_REF && TREE_CODE (TREE_OPERAND (arg, 0)) == TEMPLATE_TYPE_PARM) { cp_pedwarn ("to refer to a type member of a template parameter,"); cp_pedwarn (" use `typename %E'", arg); arg = make_typename_type (TREE_OPERAND (arg, 0), TREE_OPERAND (arg, 1)); is_type = 1; } if (is_type != requires_type) { if (in_decl) { if (complain) { cp_error ("type/value mismatch at argument %d in template parameter list for `%D'", i + 1, in_decl); if (is_type) cp_error (" expected a constant of type `%T', got `%T'", TREE_TYPE (parm), (is_tmpl_type ? DECL_NAME (arg) : arg)); else cp_error (" expected a type, got `%E'", arg); } } return error_mark_node; } if (is_tmpl_type ^ requires_tmpl_type) { if (in_decl && complain) { cp_error ("type/value mismatch at argument %d in template parameter list for `%D'", i + 1, in_decl); if (is_tmpl_type) cp_error (" expected a type, got `%T'", DECL_NAME (arg)); else cp_error (" expected a class template, got `%T'", arg); } return error_mark_node; } if (is_type) { if (requires_tmpl_type) { tree parmparm = DECL_INNERMOST_TEMPLATE_PARMS (parm); tree argparm = DECL_INNERMOST_TEMPLATE_PARMS (arg); if (coerce_template_template_parms (parmparm, argparm, in_decl, inner_args)) { val = arg; /* TEMPLATE_TEMPLATE_PARM node is preferred over TEMPLATE_DECL. */ if (val != error_mark_node && DECL_TEMPLATE_TEMPLATE_PARM_P (val)) val = TREE_TYPE (val); } else { if (in_decl && complain) { cp_error ("type/value mismatch at argument %d in template parameter list for `%D'", i + 1, in_decl); cp_error (" expected a template of type `%D', got `%D'", parm, arg); } val = error_mark_node; } } else { val = groktypename (arg); if (! processing_template_decl) { /* [basic.link]: A name with no linkage (notably, the name of a class or enumeration declared in a local scope) shall not be used to declare an entity with linkage. This implies that names with no linkage cannot be used as template arguments. */ tree t = no_linkage_check (val); if (t) { if (ANON_AGGRNAME_P (TYPE_IDENTIFIER (t))) cp_pedwarn ("template-argument `%T' uses anonymous type", val); else cp_error ("template-argument `%T' uses local type `%T'", val, t); return error_mark_node; } } } } else { tree t = tsubst (TREE_TYPE (parm), args, in_decl); if (processing_template_decl) arg = maybe_fold_nontype_arg (arg); if (!uses_template_parms (arg) && !uses_template_parms (t)) /* We used to call digest_init here. However, digest_init will report errors, which we don't want when complain is zero. More importantly, digest_init will try too hard to convert things: for example, `0' should not be converted to pointer type at this point according to the standard. Accepting this is not merely an extension, since deciding whether or not these conversions can occur is part of determining which function template to call, or whether a given epxlicit argument specification is legal. */ val = convert_nontype_argument (t, arg); else val = arg; if (val == NULL_TREE) val = error_mark_node; else if (val == error_mark_node && complain) cp_error ("could not convert template argument `%E' to `%T'", arg, t); } return val; } /* Convert all template arguments to their appropriate types, and return a vector containing the innermost resulting template arguments. If any error occurs, return error_mark_node, and, if COMPLAIN is non-zero, issue an error message. Some error messages are issued even if COMPLAIN is zero; for instance, if a template argument is composed from a local class. If REQUIRE_ALL_ARGUMENTS is non-zero, all arguments must be provided in ARGLIST, or else trailing parameters must have default values. If REQUIRE_ALL_ARGUMENTS is zero, we will attempt argument deduction for any unspecified trailing arguments. The resulting TREE_VEC is allocated on a temporary obstack, and must be explicitly copied if it will be permanent. */ static tree coerce_template_parms (parms, args, in_decl, complain, require_all_arguments) tree parms, args; tree in_decl; int complain; int require_all_arguments; { int nparms, nargs, i, lost = 0; tree inner_args; tree new_args; tree new_inner_args; inner_args = innermost_args (args); nargs = NUM_TMPL_ARGS (inner_args); nparms = TREE_VEC_LENGTH (parms); if (nargs > nparms || (nargs < nparms && require_all_arguments && TREE_PURPOSE (TREE_VEC_ELT (parms, nargs)) == NULL_TREE)) { if (complain) { cp_error ("wrong number of template arguments (%d, should be %d)", nargs, nparms); if (in_decl) cp_error_at ("provided for `%D'", in_decl); } return error_mark_node; } new_inner_args = make_temp_vec (nparms); new_args = add_outermost_template_args (args, new_inner_args); for (i = 0; i < nparms; i++) { tree arg; tree parm; /* Get the Ith template parameter. */ parm = TREE_VEC_ELT (parms, i); /* Calculate the Ith argument. */ if (inner_args && TREE_CODE (inner_args) == TREE_LIST) { arg = TREE_VALUE (inner_args); inner_args = TREE_CHAIN (inner_args); } else if (i < nargs) arg = TREE_VEC_ELT (inner_args, i); /* If no template argument was supplied, look for a default value. */ else if (TREE_PURPOSE (parm) == NULL_TREE) { /* There was no default value. */ my_friendly_assert (!require_all_arguments, 0); break; } else if (TREE_CODE (TREE_VALUE (parm)) == TYPE_DECL) arg = tsubst (TREE_PURPOSE (parm), new_args, in_decl); else arg = tsubst_expr (TREE_PURPOSE (parm), new_args, in_decl); /* Now, convert the Ith argument, as necessary. */ if (arg == NULL_TREE) /* We're out of arguments. */ { my_friendly_assert (!require_all_arguments, 0); break; } else if (arg == error_mark_node) { cp_error ("template argument %d is invalid", i + 1); arg = error_mark_node; } else arg = convert_template_argument (TREE_VALUE (parm), arg, new_args, complain, i, in_decl); if (arg == error_mark_node) lost++; TREE_VEC_ELT (new_inner_args, i) = arg; } if (lost) return error_mark_node; return new_inner_args; } /* Returns 1 if template args OT and NT are equivalent. */ int template_args_equal (ot, nt) tree ot, nt; { if (nt == ot) return 1; if (TREE_CODE (nt) != TREE_CODE (ot)) return 0; if (TREE_CODE (nt) == TREE_VEC) /* For member templates */ return comp_template_args (ot, nt); else if (TREE_CODE_CLASS (TREE_CODE (ot)) == 't') return same_type_p (ot, nt); else return (cp_tree_equal (ot, nt) > 0); } /* Returns 1 iff the OLDARGS and NEWARGS are in fact identical sets of template arguments. Returns 0 otherwise. */ int comp_template_args (oldargs, newargs) tree oldargs, newargs; { int i; if (TREE_VEC_LENGTH (oldargs) != TREE_VEC_LENGTH (newargs)) return 0; for (i = 0; i < TREE_VEC_LENGTH (oldargs); ++i) { tree nt = TREE_VEC_ELT (newargs, i); tree ot = TREE_VEC_ELT (oldargs, i); if (! template_args_equal (ot, nt)) return 0; } return 1; } /* Given class template name and parameter list, produce a user-friendly name for the instantiation. */ static char * mangle_class_name_for_template (name, parms, arglist) char *name; tree parms, arglist; { static struct obstack scratch_obstack; static char *scratch_firstobj; int i, nparms; if (!scratch_firstobj) gcc_obstack_init (&scratch_obstack); else obstack_free (&scratch_obstack, scratch_firstobj); scratch_firstobj = obstack_alloc (&scratch_obstack, 1); #define ccat(c) obstack_1grow (&scratch_obstack, (c)); #define cat(s) obstack_grow (&scratch_obstack, (s), strlen (s)) cat (name); ccat ('<'); nparms = TREE_VEC_LENGTH (parms); arglist = innermost_args (arglist); my_friendly_assert (nparms == TREE_VEC_LENGTH (arglist), 268); for (i = 0; i < nparms; i++) { tree parm = TREE_VALUE (TREE_VEC_ELT (parms, i)); tree arg = TREE_VEC_ELT (arglist, i); if (i) ccat (','); if (TREE_CODE (parm) == TYPE_DECL) { cat (type_as_string_real (arg, 0, 1)); continue; } else if (TREE_CODE (parm) == TEMPLATE_DECL) { if (TREE_CODE (arg) == TEMPLATE_DECL) { /* Already substituted with real template. Just output the template name here */ tree context = DECL_CONTEXT (arg); if (context) { my_friendly_assert (TREE_CODE (context) == NAMESPACE_DECL, 980422); cat(decl_as_string (DECL_CONTEXT (arg), 0)); cat("::"); } cat (IDENTIFIER_POINTER (DECL_NAME (arg))); } else /* Output the parameter declaration */ cat (type_as_string_real (arg, 0, 1)); continue; } else my_friendly_assert (TREE_CODE (parm) == PARM_DECL, 269); if (TREE_CODE (arg) == TREE_LIST) { /* New list cell was built because old chain link was in use. */ my_friendly_assert (TREE_PURPOSE (arg) == NULL_TREE, 270); arg = TREE_VALUE (arg); } /* No need to check arglist against parmlist here; we did that in coerce_template_parms, called from lookup_template_class. */ cat (expr_as_string (arg, 0)); } { char *bufp = obstack_next_free (&scratch_obstack); int offset = 0; while (bufp[offset - 1] == ' ') offset--; obstack_blank_fast (&scratch_obstack, offset); /* B<C<char> >, not B<C<char>> */ if (bufp[offset - 1] == '>') ccat (' '); } ccat ('>'); ccat ('\0'); return (char *) obstack_base (&scratch_obstack); } static tree classtype_mangled_name (t) tree t; { if (CLASSTYPE_TEMPLATE_INFO (t) /* Specializations have already had their names set up in lookup_template_class. */ && !CLASSTYPE_TEMPLATE_SPECIALIZATION (t)) { tree tmpl = most_general_template (CLASSTYPE_TI_TEMPLATE (t)); /* For non-primary templates, the template parameters are implicit from their surrounding context. */ if (PRIMARY_TEMPLATE_P (tmpl)) { tree name = DECL_NAME (tmpl); char *mangled_name = mangle_class_name_for_template (IDENTIFIER_POINTER (name), DECL_INNERMOST_TEMPLATE_PARMS (tmpl), CLASSTYPE_TI_ARGS (t)); tree id = get_identifier (mangled_name); IDENTIFIER_TEMPLATE (id) = name; return id; } } return TYPE_IDENTIFIER (t); } static void add_pending_template (d) tree d; { tree ti; if (TREE_CODE_CLASS (TREE_CODE (d)) == 't') ti = CLASSTYPE_TEMPLATE_INFO (d); else ti = DECL_TEMPLATE_INFO (d); if (TI_PENDING_TEMPLATE_FLAG (ti)) return; *template_tail = perm_tree_cons (build_srcloc_here (), d, NULL_TREE); template_tail = &TREE_CHAIN (*template_tail); TI_PENDING_TEMPLATE_FLAG (ti) = 1; } /* Return a TEMPLATE_ID_EXPR corresponding to the indicated FNS (which may be either a _DECL or an overloaded function or an IDENTIFIER_NODE), and ARGLIST. */ tree lookup_template_function (fns, arglist) tree fns, arglist; { tree type; if (fns == NULL_TREE) { cp_error ("non-template used as template"); return error_mark_node; } type = TREE_TYPE (fns); if (TREE_CODE (fns) == OVERLOAD || !type) type = unknown_type_node; if (processing_template_decl) return build_min (TEMPLATE_ID_EXPR, type, fns, arglist); else return build (TEMPLATE_ID_EXPR, type, fns, arglist); } /* Within the scope of a template class S<T>, the name S gets bound (in build_self_reference) to a TYPE_DECL for the class, not a TEMPLATE_DECL. If DECL is a TYPE_DECL for current_class_type, or one of its enclosing classes, and that type is a template, return the associated TEMPLATE_DECL. Otherwise, the original DECL is returned. */ tree maybe_get_template_decl_from_type_decl (decl) tree decl; { return (decl != NULL_TREE && TREE_CODE (decl) == TYPE_DECL && DECL_ARTIFICIAL (decl) && CLASSTYPE_TEMPLATE_INFO (TREE_TYPE (decl))) ? CLASSTYPE_TI_TEMPLATE (TREE_TYPE (decl)) : decl; } /* Given an IDENTIFIER_NODE (type TEMPLATE_DECL) and a chain of parameters, find the desired type. D1 is the PTYPENAME terminal, and ARGLIST is the list of arguments. (Actually ARGLIST may be either a TREE_LIST or a TREE_VEC. It will be a TREE_LIST if called directly from the parser, and a TREE_VEC otherwise.) Since ARGLIST is build on the decl_obstack, we must copy it here to keep it from being reclaimed when the decl storage is reclaimed. IN_DECL, if non-NULL, is the template declaration we are trying to instantiate. If ENTERING_SCOPE is non-zero, we are about to enter the scope of the class we are looking up. If the template class is really a local class in a template function, then the FUNCTION_CONTEXT is the function in which it is being instantiated. */ tree lookup_template_class (d1, arglist, in_decl, context, entering_scope) tree d1, arglist; tree in_decl; tree context; int entering_scope; { tree template = NULL_TREE, parmlist; tree t; if (TREE_CODE (d1) == IDENTIFIER_NODE) { if (IDENTIFIER_LOCAL_VALUE (d1) && DECL_TEMPLATE_TEMPLATE_PARM_P (IDENTIFIER_LOCAL_VALUE (d1))) template = IDENTIFIER_LOCAL_VALUE (d1); else { if (context) push_decl_namespace (context); if (current_class_type != NULL_TREE) template = maybe_get_template_decl_from_type_decl (IDENTIFIER_CLASS_VALUE (d1)); if (template == NULL_TREE) template = lookup_name_nonclass (d1); if (context) pop_decl_namespace (); } if (template) context = DECL_CONTEXT (template); } else if (TREE_CODE (d1) == TYPE_DECL && IS_AGGR_TYPE (TREE_TYPE (d1))) { if (CLASSTYPE_TEMPLATE_INFO (TREE_TYPE (d1)) == NULL_TREE) return error_mark_node; template = CLASSTYPE_TI_TEMPLATE (TREE_TYPE (d1)); d1 = DECL_NAME (template); } else if (TREE_CODE (d1) == ENUMERAL_TYPE || (TREE_CODE_CLASS (TREE_CODE (d1)) == 't' && IS_AGGR_TYPE (d1))) { template = TYPE_TI_TEMPLATE (d1); d1 = DECL_NAME (template); } else if (TREE_CODE (d1) == TEMPLATE_DECL && TREE_CODE (DECL_RESULT (d1)) == TYPE_DECL) { template = d1; d1 = DECL_NAME (template); context = DECL_CONTEXT (template); } else my_friendly_abort (272); /* With something like `template <class T> class X class X { ... };' we could end up with D1 having nothing but an IDENTIFIER_LOCAL_VALUE. We don't want to do that, but we have to deal with the situation, so let's give them some syntax errors to chew on instead of a crash. */ if (! template) return error_mark_node; if (context == NULL_TREE) context = global_namespace; if (TREE_CODE (template) != TEMPLATE_DECL) { cp_error ("non-template type `%T' used as a template", d1); if (in_decl) cp_error_at ("for template declaration `%D'", in_decl); return error_mark_node; } if (DECL_TEMPLATE_TEMPLATE_PARM_P (template)) { /* Create a new TEMPLATE_DECL and TEMPLATE_TEMPLATE_PARM node to store template arguments */ tree parm = copy_template_template_parm (TREE_TYPE (template)); tree template2 = TYPE_STUB_DECL (parm); tree arglist2; parmlist = DECL_INNERMOST_TEMPLATE_PARMS (template); arglist2 = coerce_template_parms (parmlist, arglist, template, 1, 1); if (arglist2 == error_mark_node) return error_mark_node; arglist2 = copy_to_permanent (arglist2); TEMPLATE_TEMPLATE_PARM_TEMPLATE_INFO (parm) = perm_tree_cons (template2, arglist2, NULL_TREE); TYPE_SIZE (parm) = 0; return parm; } else { tree template_type = TREE_TYPE (template); tree type_decl; tree found = NULL_TREE; int arg_depth; int parm_depth; int is_partial_instantiation; template = most_general_template (template); parmlist = DECL_TEMPLATE_PARMS (template); parm_depth = TMPL_PARMS_DEPTH (parmlist); arg_depth = TMPL_ARGS_DEPTH (arglist); /* We build up the coerced arguments and such on the momentary_obstack. */ push_momentary (); if (arg_depth == 1 && parm_depth > 1) { /* We've been given an incomplete set of template arguments. For example, given: template <class T> struct S1 { template <class U> struct S2 {}; template <class U> struct S2<U*> {}; }; we will be called with an ARGLIST of `U*', but the TEMPLATE will be `template <class T> template <class U> struct S1<T>::S2'. We must fill in the missing arguments. */ my_friendly_assert (context != NULL_TREE, 0); while (!IS_AGGR_TYPE_CODE (TREE_CODE (context)) && context != global_namespace) context = DECL_REAL_CONTEXT (context); if (context == global_namespace) /* This is bad. We cannot get enough arguments, even from the surrounding context, to resolve this class. One case where this might happen is (illegal) code like: template <class U> template <class T> struct S { A(const A<T>& a) {} }; We should catch this error sooner (at the opening curly for `S', but it is better to be safe than sorry here. */ { cp_error ("invalid use of `%D'", template); return error_mark_node; } arglist = add_to_template_args (TYPE_TI_ARGS (context), arglist); arg_depth = TMPL_ARGS_DEPTH (arglist); } my_friendly_assert (parm_depth == arg_depth, 0); /* Calculate the BOUND_ARGS. These will be the args that are actually tsubst'd into the definition to create the instantiation. */ if (parm_depth > 1) { /* We have multiple levels of arguments to coerce, at once. */ int i; int saved_depth = TMPL_ARGS_DEPTH (arglist); tree bound_args = make_temp_vec (parm_depth); for (i = saved_depth, t = DECL_TEMPLATE_PARMS (template); i > 0 && t != NULL_TREE; --i, t = TREE_CHAIN (t)) { tree a = coerce_template_parms (TREE_VALUE (t), arglist, template, 1, 1); SET_TMPL_ARGS_LEVEL (bound_args, i, a); /* We temporarily reduce the length of the ARGLIST so that coerce_template_parms will see only the arguments corresponding to the template parameters it is examining. */ TREE_VEC_LENGTH (arglist)--; } /* Restore the ARGLIST to its full size. */ TREE_VEC_LENGTH (arglist) = saved_depth; arglist = bound_args; } else arglist = coerce_template_parms (INNERMOST_TEMPLATE_PARMS (parmlist), innermost_args (arglist), template, 1, 1); if (arglist == error_mark_node) /* We were unable to bind the arguments. */ return error_mark_node; /* In the scope of a template class, explicit references to the template class refer to the type of the template, not any instantiation of it. For example, in: template <class T> class C { void f(C<T>); } the `C<T>' is just the same as `C'. Outside of the class, however, such a reference is an instantiation. */ if (comp_template_args (TYPE_TI_ARGS (template_type), arglist)) { found = template_type; if (!entering_scope && PRIMARY_TEMPLATE_P (template)) { tree ctx; /* Note that we use DECL_CONTEXT, rather than CP_DECL_CONTEXT, so that the termination test is always just `ctx'. We're not interested in namepace scopes. */ for (ctx = current_class_type; ctx; ctx = (TREE_CODE_CLASS (TREE_CODE (ctx)) == 't') ? TYPE_CONTEXT (ctx) : DECL_CONTEXT (ctx)) if (same_type_p (ctx, template_type)) break; if (!ctx) /* We're not in the scope of the class, so the TEMPLATE_TYPE is not the type we want after all. */ found = NULL_TREE; } } if (!found) { for (found = DECL_TEMPLATE_INSTANTIATIONS (template); found; found = TREE_CHAIN (found)) if (comp_template_args (TREE_PURPOSE (found), arglist)) break; if (found) found = TREE_VALUE (found); } if (found) { pop_momentary (); return found; } /* Since we didn't find the type, we'll have to create it. Since we'll be saving this type on the DECL_TEMPLATE_INSTANTIATIONS list, it must be permanent. */ push_obstacks (&permanent_obstack, &permanent_obstack); /* This type is a "partial instantiation" if any of the template arguments still inolve template parameters. Note that we set IS_PARTIAL_INSTANTIATION for partial specializations as well. */ is_partial_instantiation = uses_template_parms (arglist); /* Create the type. */ if (TREE_CODE (template_type) == ENUMERAL_TYPE) { if (!is_partial_instantiation) t = start_enum (TYPE_IDENTIFIER (template_type)); else /* We don't want to call start_enum for this type, since the values for the enumeration constants may involve template parameters. And, no one should be interested in the enumeration constants for such a type. */ t = make_node (ENUMERAL_TYPE); } else { t = make_lang_type (TREE_CODE (template_type)); CLASSTYPE_DECLARED_CLASS (t) = CLASSTYPE_DECLARED_CLASS (template_type); CLASSTYPE_GOT_SEMICOLON (t) = 1; SET_CLASSTYPE_IMPLICIT_INSTANTIATION (t); TYPE_FOR_JAVA (t) = TYPE_FOR_JAVA (template_type); } /* If we called start_enum above, this information will already be set up. */ if (!TYPE_NAME (t)) { TYPE_CONTEXT (t) = FROB_CONTEXT (context); /* Create a stub TYPE_DECL for it. */ type_decl = build_decl (TYPE_DECL, DECL_NAME (template), t); SET_DECL_ARTIFICIAL (type_decl); DECL_CONTEXT (type_decl) = TYPE_CONTEXT (t); DECL_SOURCE_FILE (type_decl) = DECL_SOURCE_FILE (TYPE_STUB_DECL (template_type)); DECL_SOURCE_LINE (type_decl) = DECL_SOURCE_LINE (TYPE_STUB_DECL (template_type)); TYPE_STUB_DECL (t) = TYPE_NAME (t) = type_decl; } else type_decl = TYPE_NAME (t); /* Set up the template information. We have to figure out which template is the immediate parent if this is a full instantiation. */ if (parm_depth == 1 || is_partial_instantiation || !PRIMARY_TEMPLATE_P (template)) /* This case is easy; there are no member templates involved. */ found = template; else { /* This is a full instantiation of a member template. There should be some partial instantiation of which this is an instance. */ for (found = DECL_TEMPLATE_INSTANTIATIONS (template); found; found = TREE_CHAIN (found)) { int success; tree tmpl = CLASSTYPE_TI_TEMPLATE (TREE_VALUE (found)); /* We only want partial instantiations, here, not specializations or full instantiations. */ if (CLASSTYPE_TEMPLATE_SPECIALIZATION (TREE_VALUE (found)) || !uses_template_parms (TREE_VALUE (found))) continue; /* Temporarily reduce by one the number of levels in the ARGLIST and in FOUND so as to avoid comparing the last set of arguments. */ TREE_VEC_LENGTH (arglist)--; TREE_VEC_LENGTH (TREE_PURPOSE (found)) --; /* See if the arguments match. If they do, then TMPL is the partial instantiation we want. */ success = comp_template_args (TREE_PURPOSE (found), arglist); /* Restore the argument vectors to their full size. */ TREE_VEC_LENGTH (arglist)++; TREE_VEC_LENGTH (TREE_PURPOSE (found))++; if (success) { found = tmpl; break; } } if (!found) my_friendly_abort (0); } arglist = copy_to_permanent (arglist); SET_TYPE_TEMPLATE_INFO (t, tree_cons (found, arglist, NULL_TREE)); DECL_TEMPLATE_INSTANTIATIONS (template) = tree_cons (arglist, t, DECL_TEMPLATE_INSTANTIATIONS (template)); if (TREE_CODE (t) == ENUMERAL_TYPE && !is_partial_instantiation) /* Now that the type has been registered on the instantiations list, we set up the enumerators. Because the enumeration constants may involve the enumeration type itself, we make sure to register the type first, and then create the constants. That way, doing tsubst_expr for the enumeration constants won't result in recursive calls here; we'll find the instantiation and exit above. */ tsubst_enum (template_type, t, arglist); /* We're done with the permanent obstack, now. */ pop_obstacks (); /* We're also done with the momentary allocation we started above. */ pop_momentary (); /* Reset the name of the type, now that CLASSTYPE_TEMPLATE_INFO is set up. */ if (TREE_CODE (t) != ENUMERAL_TYPE) DECL_NAME (type_decl) = classtype_mangled_name (t); DECL_ASSEMBLER_NAME (type_decl) = DECL_NAME (type_decl); if (!is_partial_instantiation) { DECL_ASSEMBLER_NAME (type_decl) = get_identifier (build_overload_name (t, 1, 1)); /* For backwards compatibility; code that uses -fexternal-templates expects looking up a template to instantiate it. I think DDD still relies on this. (jason 8/20/1998) */ if (TREE_CODE (t) != ENUMERAL_TYPE && flag_external_templates && CLASSTYPE_INTERFACE_KNOWN (TREE_TYPE (template)) && ! CLASSTYPE_INTERFACE_ONLY (TREE_TYPE (template))) add_pending_template (t); } else /* If the type makes use of template parameters, the code that generates debugging information will crash. */ DECL_IGNORED_P (TYPE_STUB_DECL (t)) = 1; return t; } } /* For each TEMPLATE_TYPE_PARM, TEMPLATE_TEMPLATE_PARM, or TEMPLATE_PARM_INDEX in T, call FN with the parameter and the DATA. If FN returns non-zero, the iteration is terminated, and for_each_template_parm returns 1. Otherwise, the iteration continues. If FN never returns a non-zero value, the value returned by for_each_template_parm is 0. If FN is NULL, it is considered to be the function which always returns 1. */ int for_each_template_parm (t, fn, data) tree t; tree_fn_t fn; void* data; { if (!t) return 0; if (TREE_CODE_CLASS (TREE_CODE (t)) == 't' && for_each_template_parm (TYPE_CONTEXT (t), fn, data)) return 1; switch (TREE_CODE (t)) { case INDIRECT_REF: case COMPONENT_REF: /* We assume that the object must be instantiated in order to build the COMPONENT_REF, so we test only whether the type of the COMPONENT_REF uses template parms. */ return for_each_template_parm (TREE_TYPE (t), fn, data); case IDENTIFIER_NODE: if (!IDENTIFIER_TEMPLATE (t)) return 0; my_friendly_abort (42); /* aggregates of tree nodes */ case TREE_VEC: { int i = TREE_VEC_LENGTH (t); while (i--) if (for_each_template_parm (TREE_VEC_ELT (t, i), fn, data)) return 1; return 0; } case TREE_LIST: if (for_each_template_parm (TREE_PURPOSE (t), fn, data) || for_each_template_parm (TREE_VALUE (t), fn, data)) return 1; return for_each_template_parm (TREE_CHAIN (t), fn, data); case OVERLOAD: if (for_each_template_parm (OVL_FUNCTION (t), fn, data)) return 1; return for_each_template_parm (OVL_CHAIN (t), fn, data); /* constructed type nodes */ case POINTER_TYPE: case REFERENCE_TYPE: return for_each_template_parm (TREE_TYPE (t), fn, data); case RECORD_TYPE: if (TYPE_PTRMEMFUNC_FLAG (t)) return for_each_template_parm (TYPE_PTRMEMFUNC_FN_TYPE (t), fn, data); /* Fall through. */ case UNION_TYPE: case ENUMERAL_TYPE: if (! TYPE_TEMPLATE_INFO (t)) return 0; return for_each_template_parm (TREE_VALUE (TYPE_TEMPLATE_INFO (t)), fn, data); case METHOD_TYPE: if (for_each_template_parm (TYPE_METHOD_BASETYPE (t), fn, data)) return 1; /* Fall through. */ case FUNCTION_TYPE: /* Check the parameter types. Since default arguments are not instantiated until they are needed, the TYPE_ARG_TYPES may contain expressions that involve template parameters. But, no-one should be looking at them yet. And, once they're instantiated, they don't contain template parameters, so there's no point in looking at them then, either. */ { tree parm; for (parm = TYPE_ARG_TYPES (t); parm; parm = TREE_CHAIN (parm)) if (for_each_template_parm (TREE_VALUE (parm), fn, data)) return 1; } /* Check the return type, too. */ return for_each_template_parm (TREE_TYPE (t), fn, data); case ARRAY_TYPE: if (for_each_template_parm (TYPE_DOMAIN (t), fn, data)) return 1; return for_each_template_parm (TREE_TYPE (t), fn, data); case OFFSET_TYPE: if (for_each_template_parm (TYPE_OFFSET_BASETYPE (t), fn, data)) return 1; return for_each_template_parm (TREE_TYPE (t), fn, data); /* decl nodes */ case TYPE_DECL: return for_each_template_parm (TREE_TYPE (t), fn, data); case TEMPLATE_DECL: /* A template template parameter is encountered */ if (DECL_TEMPLATE_TEMPLATE_PARM_P (t)) return for_each_template_parm (TREE_TYPE (t), fn, data); /* Already substituted template template parameter */ return 0; case CONST_DECL: if (for_each_template_parm (DECL_INITIAL (t), fn, data)) return 1; goto check_type_and_context; case FUNCTION_DECL: case VAR_DECL: /* ??? What about FIELD_DECLs? */ if (DECL_LANG_SPECIFIC (t) && DECL_TEMPLATE_INFO (t) && for_each_template_parm (DECL_TI_ARGS (t), fn, data)) return 1; /* fall through */ case PARM_DECL: check_type_and_context: if (for_each_template_parm (TREE_TYPE (t), fn, data)) return 1; if (DECL_CONTEXT (t) && for_each_template_parm (DECL_CONTEXT (t), fn, data)) return 1; return 0; case CALL_EXPR: return for_each_template_parm (TREE_TYPE (t), fn, data); case ADDR_EXPR: return for_each_template_parm (TREE_OPERAND (t, 0), fn, data); /* template parm nodes */ case TEMPLATE_TEMPLATE_PARM: /* Record template parameters such as `T' inside `TT<T>'. */ if (TEMPLATE_TEMPLATE_PARM_TEMPLATE_INFO (t) && for_each_template_parm (TYPE_TI_ARGS (t), fn, data)) return 1; case TEMPLATE_TYPE_PARM: case TEMPLATE_PARM_INDEX: if (fn) return (*fn)(t, data); else return 1; /* simple type nodes */ case INTEGER_TYPE: if (for_each_template_parm (TYPE_MIN_VALUE (t), fn, data)) return 1; return for_each_template_parm (TYPE_MAX_VALUE (t), fn, data); case REAL_TYPE: case COMPLEX_TYPE: case VOID_TYPE: case BOOLEAN_TYPE: case NAMESPACE_DECL: return 0; /* constants */ case INTEGER_CST: case REAL_CST: case STRING_CST: return 0; case ERROR_MARK: /* Non-error_mark_node ERROR_MARKs are bad things. */ my_friendly_assert (t == error_mark_node, 274); /* NOTREACHED */ return 0; case LOOKUP_EXPR: case TYPENAME_TYPE: return 1; case PTRMEM_CST: return for_each_template_parm (TREE_TYPE (t), fn, data); case SCOPE_REF: return for_each_template_parm (TREE_OPERAND (t, 0), fn, data); case CONSTRUCTOR: if (TREE_TYPE (t) && TYPE_PTRMEMFUNC_P (TREE_TYPE (t))) return for_each_template_parm (TYPE_PTRMEMFUNC_FN_TYPE (TREE_TYPE (t)), fn, data); return for_each_template_parm (TREE_OPERAND (t, 1), fn, data); case MODOP_EXPR: case CAST_EXPR: case REINTERPRET_CAST_EXPR: case CONST_CAST_EXPR: case STATIC_CAST_EXPR: case DYNAMIC_CAST_EXPR: case ARROW_EXPR: case DOTSTAR_EXPR: case TYPEID_EXPR: return 1; case SIZEOF_EXPR: case ALIGNOF_EXPR: return for_each_template_parm (TREE_OPERAND (t, 0), fn, data); default: switch (TREE_CODE_CLASS (TREE_CODE (t))) { case '1': case '2': case 'e': case '<': { int i; for (i = first_rtl_op (TREE_CODE (t)); --i >= 0;) if (for_each_template_parm (TREE_OPERAND (t, i), fn, data)) return 1; return 0; } default: break; } sorry ("testing %s for template parms", tree_code_name [(int) TREE_CODE (t)]); my_friendly_abort (82); /* NOTREACHED */ return 0; } } int uses_template_parms (t) tree t; { return for_each_template_parm (t, 0, 0); } static struct tinst_level *current_tinst_level; static struct tinst_level *free_tinst_level; static int tinst_depth; extern int max_tinst_depth; #ifdef GATHER_STATISTICS int depth_reached; #endif int tinst_level_tick; int last_template_error_tick; /* Print out all the template instantiations that we are currently working on. If ERR, we are being called from cp_thing, so do the right thing for an error message. */ static void print_template_context (err) int err; { struct tinst_level *p = current_tinst_level; int line = lineno; char *file = input_filename; if (err && p) { if (current_function_decl != p->decl && current_function_decl != NULL_TREE) /* We can get here during the processing of some synthesized method. Then, p->decl will be the function that's causing the synthesis. */ ; else { if (current_function_decl == p->decl) /* Avoid redundancy with the the "In function" line. */; else fprintf (stderr, "%s: In instantiation of `%s':\n", file, decl_as_string (p->decl, 0)); line = p->line; file = p->file; p = p->next; } } for (; p; p = p->next) { fprintf (stderr, "%s:%d: instantiated from `%s'\n", file, line, decl_as_string (p->decl, 0)); line = p->line; file = p->file; } fprintf (stderr, "%s:%d: instantiated from here\n", file, line); } /* Called from cp_thing to print the template context for an error. */ void maybe_print_template_context () { if (last_template_error_tick == tinst_level_tick || current_tinst_level == 0) return; last_template_error_tick = tinst_level_tick; print_template_context (1); } static int push_tinst_level (d) tree d; { struct tinst_level *new; if (tinst_depth >= max_tinst_depth) { /* If the instantiation in question still has unbound template parms, we don't really care if we can't instantiate it, so just return. This happens with base instantiation for implicit `typename'. */ if (uses_template_parms (d)) return 0; last_template_error_tick = tinst_level_tick; error ("template instantiation depth exceeds maximum of %d", max_tinst_depth); error (" (use -ftemplate-depth-NN to increase the maximum)"); cp_error (" instantiating `%D'", d); print_template_context (0); return 0; } if (free_tinst_level) { new = free_tinst_level; free_tinst_level = new->next; } else new = (struct tinst_level *) xmalloc (sizeof (struct tinst_level)); new->decl = d; new->line = lineno; new->file = input_filename; new->next = current_tinst_level; current_tinst_level = new; ++tinst_depth; #ifdef GATHER_STATISTICS if (tinst_depth > depth_reached) depth_reached = tinst_depth; #endif ++tinst_level_tick; return 1; } void pop_tinst_level () { struct tinst_level *old = current_tinst_level; /* Restore the filename and line number stashed away when we started this instantiation. */ lineno = old->line; input_filename = old->file; extract_interface_info (); current_tinst_level = old->next; old->next = free_tinst_level; free_tinst_level = old; --tinst_depth; ++tinst_level_tick; } struct tinst_level * tinst_for_decl () { struct tinst_level *p = current_tinst_level; if (p) for (; p->next ; p = p->next ) ; return p; } /* DECL is a friend FUNCTION_DECL or TEMPLATE_DECL. ARGS is the vector of template arguments, as for tsubst. Returns an appropriate tsbust'd friend declaration. */ static tree tsubst_friend_function (decl, args) tree decl; tree args; { tree new_friend; int line = lineno; char *file = input_filename; lineno = DECL_SOURCE_LINE (decl); input_filename = DECL_SOURCE_FILE (decl); if (TREE_CODE (decl) == FUNCTION_DECL && DECL_TEMPLATE_INSTANTIATION (decl) && TREE_CODE (DECL_TI_TEMPLATE (decl)) != TEMPLATE_DECL) /* This was a friend declared with an explicit template argument list, e.g.: friend void f<>(T); to indicate that f was a template instantiation, not a new function declaration. Now, we have to figure out what instantiation of what template. */ { tree template_id; tree new_args; tree tmpl; template_id = lookup_template_function (tsubst_expr (DECL_TI_TEMPLATE (decl), args, NULL_TREE), tsubst (DECL_TI_ARGS (decl), args, NULL_TREE)); /* FIXME: The decl we create via the next tsubst could be created on a temporary obstack. */ new_friend = tsubst (decl, args, NULL_TREE); tmpl = determine_specialization (template_id, new_friend, &new_args, /*need_member_template=*/0, /*complain=*/1); new_friend = instantiate_template (tmpl, new_args); goto done; } new_friend = tsubst (decl, args, NULL_TREE); /* The NEW_FRIEND will look like an instantiation, to the compiler, but is not an instantiation from the point of view of the language. For example, we might have had: template <class T> struct S { template <class U> friend void f(T, U); }; Then, in S<int>, template <class U> void f(int, U) is not an instantiation of anything. */ DECL_USE_TEMPLATE (new_friend) = 0; if (TREE_CODE (decl) == TEMPLATE_DECL) DECL_USE_TEMPLATE (DECL_TEMPLATE_RESULT (new_friend)) = 0; /* The mangled name for the NEW_FRIEND is incorrect. The call to tsubst will have resulted in a call to set_mangled_name_for_template_decl. But, the function is not a template instantiation and should not be mangled like one. Therefore, we remangle the function name. We don't have to do this if the NEW_FRIEND is a template since set_mangled_name_for_template_decl doesn't do anything if the function declaration still uses template arguments. */ if (TREE_CODE (new_friend) != TEMPLATE_DECL) { set_mangled_name_for_decl (new_friend); DECL_RTL (new_friend) = 0; make_decl_rtl (new_friend, NULL_PTR, 1); } if (DECL_NAMESPACE_SCOPE_P (new_friend)) { tree old_decl; tree new_friend_template_info; tree new_friend_result_template_info; int new_friend_is_defn; /* We must save some information from NEW_FRIEND before calling duplicate decls since that function will free NEW_FRIEND if possible. */ new_friend_template_info = DECL_TEMPLATE_INFO (new_friend); if (TREE_CODE (new_friend) == TEMPLATE_DECL) { /* This declaration is a `primary' template. */ DECL_PRIMARY_TEMPLATE (new_friend) = new_friend; new_friend_is_defn = DECL_INITIAL (DECL_RESULT (new_friend)) != NULL_TREE; new_friend_result_template_info = DECL_TEMPLATE_INFO (DECL_RESULT (new_friend)); } else { new_friend_is_defn = DECL_INITIAL (new_friend) != NULL_TREE; new_friend_result_template_info = NULL_TREE; } old_decl = pushdecl_namespace_level (new_friend); if (old_decl != new_friend) { /* This new friend declaration matched an existing declaration. For example, given: template <class T> void f(T); template <class U> class C { template <class T> friend void f(T) {} }; the friend declaration actually provides the definition of `f', once C has been instantiated for some type. So, old_decl will be the out-of-class template declaration, while new_friend is the in-class definition. But, if `f' was called before this point, the instantiation of `f' will have DECL_TI_ARGS corresponding to `T' but not to `U', references to which might appear in the definition of `f'. Previously, the most general template for an instantiation of `f' was the out-of-class version; now it is the in-class version. Therefore, we run through all specialization of `f', adding to their DECL_TI_ARGS appropriately. In particular, they need a new set of outer arguments, corresponding to the arguments for this class instantiation. The same situation can arise with something like this: friend void f(int); template <class T> class C { friend void f(T) {} }; when `C<int>' is instantiated. Now, `f(int)' is defined in the class. */ if (!new_friend_is_defn) /* On the other hand, if the in-class declaration does *not* provide a definition, then we don't want to alter existing definitions. We can just leave everything alone. */ ; else { /* Overwrite whatever template info was there before, if any, with the new template information pertaining to the declaration. */ DECL_TEMPLATE_INFO (old_decl) = new_friend_template_info; if (TREE_CODE (old_decl) != TEMPLATE_DECL) /* duplicate_decls will take care of this case. */ ; else { tree t; tree new_friend_args; DECL_TEMPLATE_INFO (DECL_RESULT (old_decl)) = new_friend_result_template_info; new_friend_args = TI_ARGS (new_friend_template_info); for (t = DECL_TEMPLATE_SPECIALIZATIONS (old_decl); t != NULL_TREE; t = TREE_CHAIN (t)) { tree spec = TREE_VALUE (t); DECL_TI_ARGS (spec) = add_outermost_template_args (new_friend_args, DECL_TI_ARGS (spec)); DECL_TI_ARGS (spec) = copy_to_permanent (DECL_TI_ARGS (spec)); } /* Now, since specializations are always supposed to hang off of the most general template, we must move them. */ t = most_general_template (old_decl); if (t != old_decl) { DECL_TEMPLATE_SPECIALIZATIONS (t) = chainon (DECL_TEMPLATE_SPECIALIZATIONS (t), DECL_TEMPLATE_SPECIALIZATIONS (old_decl)); DECL_TEMPLATE_SPECIALIZATIONS (old_decl) = NULL_TREE; } } } /* The information from NEW_FRIEND has been merged into OLD_DECL by duplicate_decls. */ new_friend = old_decl; } } else if (TYPE_SIZE (DECL_CONTEXT (new_friend))) { /* Check to see that the declaration is really present, and, possibly obtain an improved declaration. */ tree fn = check_classfn (DECL_CONTEXT (new_friend), new_friend); if (fn) new_friend = fn; } done: lineno = line; input_filename = file; return new_friend; } /* FRIEND_TMPL is a friend TEMPLATE_DECL. ARGS is the vector of template arguments, as for tsubst. Returns an appropriate tsbust'd friend type. */ static tree tsubst_friend_class (friend_tmpl, args) tree friend_tmpl; tree args; { tree friend_type; tree tmpl = lookup_name (DECL_NAME (friend_tmpl), 1); tmpl = maybe_get_template_decl_from_type_decl (tmpl); if (tmpl != NULL_TREE && DECL_CLASS_TEMPLATE_P (tmpl)) { /* The friend template has already been declared. Just check to see that the declarations match, and install any new default parameters. We must tsubst the default parameters, of course. We only need the innermost template parameters because that is all that redeclare_class_template will look at. */ tree parms = tsubst_template_parms (DECL_TEMPLATE_PARMS (friend_tmpl), args); redeclare_class_template (TREE_TYPE (tmpl), parms); friend_type = TREE_TYPE (tmpl); } else { /* The friend template has not already been declared. In this case, the instantiation of the template class will cause the injection of this template into the global scope. */ tmpl = tsubst (friend_tmpl, args, NULL_TREE); /* The new TMPL is not an instantiation of anything, so we forget its origins. We don't reset CLASSTYPE_TI_TEMPLATE for the new type because that is supposed to be the corresponding template decl, i.e., TMPL. */ DECL_USE_TEMPLATE (tmpl) = 0; DECL_TEMPLATE_INFO (tmpl) = NULL_TREE; CLASSTYPE_USE_TEMPLATE (TREE_TYPE (tmpl)) = 0; /* Inject this template into the global scope. */ friend_type = TREE_TYPE (pushdecl_top_level (tmpl)); } return friend_type; } tree instantiate_class_template (type) tree type; { tree template, args, pattern, t; tree typedecl; if (type == error_mark_node) return error_mark_node; if (TYPE_BEING_DEFINED (type) || TYPE_SIZE (type)) return type; /* We want to allocate temporary vectors of template arguments and template argument expressions on the momentary obstack, not on the expression obstack. Otherwise, all the space allocated in argument coercion and such is simply lost. */ push_momentary (); template = most_general_template (CLASSTYPE_TI_TEMPLATE (type)); args = CLASSTYPE_TI_ARGS (type); my_friendly_assert (TREE_CODE (template) == TEMPLATE_DECL, 279); t = most_specialized_class (template, args); if (t == error_mark_node) { char *str = "candidates are:"; cp_error ("ambiguous class template instantiation for `%#T'", type); for (t = DECL_TEMPLATE_SPECIALIZATIONS (template); t; t = TREE_CHAIN (t)) { if (get_class_bindings (TREE_VALUE (t), TREE_PURPOSE (t), args)) { cp_error_at ("%s %+#T", str, TREE_TYPE (t)); str = " "; } } TYPE_BEING_DEFINED (type) = 1; type = error_mark_node; goto end; } else if (t) pattern = TREE_TYPE (t); else pattern = TREE_TYPE (template); if (TYPE_SIZE (pattern) == NULL_TREE) goto end; if (t) { /* This TYPE is actually a instantiation of of a partial specialization. We replace the innermost set of ARGS with the arguments appropriate for substitution. For example, given: template <class T> struct S {}; template <class T> struct S<T*> {}; and supposing that we are instantiating S<int*>, ARGS will present be {int*} but we need {int}. */ tree inner_args = get_class_bindings (TREE_VALUE (t), TREE_PURPOSE (t), args); /* If there were multiple levels in ARGS, replacing the innermost level would alter CLASSTYPE_TI_ARGS, which we don't want, so we make a copy first. */ if (TMPL_ARGS_HAVE_MULTIPLE_LEVELS (args)) { args = copy_node (args); SET_TMPL_ARGS_LEVEL (args, TMPL_ARGS_DEPTH (args), inner_args); } else args = inner_args; } if (pedantic && uses_template_parms (args)) { /* If there are still template parameters amongst the args, then we can't instantiate the type; there's no telling whether or not one of the template parameters might eventually be instantiated to some value that results in a specialization being used. We do the type as complete so that, for example, declaring one of its members to be a friend will not be rejected. */ TYPE_SIZE (type) = integer_zero_node; goto end; } TYPE_BEING_DEFINED (type) = 1; if (! push_tinst_level (type)) goto end; maybe_push_to_top_level (uses_template_parms (type)); pushclass (type, 0); /* We must copy the arguments to the permanent obstack since during the tsubst'ing below they may wind up in the DECL_TI_ARGS of some instantiated member template. */ args = copy_to_permanent (args); if (flag_external_templates) { if (flag_alt_external_templates) { CLASSTYPE_INTERFACE_ONLY (type) = interface_only; SET_CLASSTYPE_INTERFACE_UNKNOWN_X (type, interface_unknown); CLASSTYPE_VTABLE_NEEDS_WRITING (type) = (! CLASSTYPE_INTERFACE_ONLY (type) && CLASSTYPE_INTERFACE_KNOWN (type)); } else { CLASSTYPE_INTERFACE_ONLY (type) = CLASSTYPE_INTERFACE_ONLY (pattern); SET_CLASSTYPE_INTERFACE_UNKNOWN_X (type, CLASSTYPE_INTERFACE_UNKNOWN (pattern)); CLASSTYPE_VTABLE_NEEDS_WRITING (type) = (! CLASSTYPE_INTERFACE_ONLY (type) && CLASSTYPE_INTERFACE_KNOWN (type)); } } else { SET_CLASSTYPE_INTERFACE_UNKNOWN (type); CLASSTYPE_VTABLE_NEEDS_WRITING (type) = 1; } TYPE_HAS_CONSTRUCTOR (type) = TYPE_HAS_CONSTRUCTOR (pattern); TYPE_HAS_DESTRUCTOR (type) = TYPE_HAS_DESTRUCTOR (pattern); TYPE_HAS_ASSIGNMENT (type) = TYPE_HAS_ASSIGNMENT (pattern); TYPE_OVERLOADS_CALL_EXPR (type) = TYPE_OVERLOADS_CALL_EXPR (pattern); TYPE_OVERLOADS_ARRAY_REF (type) = TYPE_OVERLOADS_ARRAY_REF (pattern); TYPE_OVERLOADS_ARROW (type) = TYPE_OVERLOADS_ARROW (pattern); TYPE_GETS_NEW (type) = TYPE_GETS_NEW (pattern); TYPE_GETS_DELETE (type) = TYPE_GETS_DELETE (pattern); TYPE_VEC_DELETE_TAKES_SIZE (type) = TYPE_VEC_DELETE_TAKES_SIZE (pattern); TYPE_HAS_ASSIGN_REF (type) = TYPE_HAS_ASSIGN_REF (pattern); TYPE_HAS_CONST_ASSIGN_REF (type) = TYPE_HAS_CONST_ASSIGN_REF (pattern); TYPE_HAS_ABSTRACT_ASSIGN_REF (type) = TYPE_HAS_ABSTRACT_ASSIGN_REF (pattern); TYPE_HAS_INIT_REF (type) = TYPE_HAS_INIT_REF (pattern); TYPE_HAS_CONST_INIT_REF (type) = TYPE_HAS_CONST_INIT_REF (pattern); TYPE_HAS_DEFAULT_CONSTRUCTOR (type) = TYPE_HAS_DEFAULT_CONSTRUCTOR (pattern); TYPE_HAS_CONVERSION (type) = TYPE_HAS_CONVERSION (pattern); TYPE_USES_COMPLEX_INHERITANCE (type) = TYPE_USES_COMPLEX_INHERITANCE (pattern); TYPE_USES_MULTIPLE_INHERITANCE (type) = TYPE_USES_MULTIPLE_INHERITANCE (pattern); TYPE_USES_VIRTUAL_BASECLASSES (type) = TYPE_USES_VIRTUAL_BASECLASSES (pattern); TYPE_PACKED (type) = TYPE_PACKED (pattern); TYPE_ALIGN (type) = TYPE_ALIGN (pattern); TYPE_FOR_JAVA (type) = TYPE_FOR_JAVA (pattern); /* For libjava's JArray<T> */ /* If this is a partial instantiation, don't tsubst anything. We will only use this type for implicit typename, so the actual contents don't matter. All that matters is whether a particular name is a type. */ if (uses_template_parms (type)) { TYPE_BINFO_BASETYPES (type) = TYPE_BINFO_BASETYPES (pattern); TYPE_FIELDS (type) = TYPE_FIELDS (pattern); TYPE_METHODS (type) = TYPE_METHODS (pattern); CLASSTYPE_TAGS (type) = CLASSTYPE_TAGS (pattern); TYPE_SIZE (type) = integer_zero_node; goto done_with_instantiation; } { tree binfo = TYPE_BINFO (type); tree pbases = TYPE_BINFO_BASETYPES (pattern); if (pbases) { tree bases; int i; int len = TREE_VEC_LENGTH (pbases); bases = make_tree_vec (len); for (i = 0; i < len; ++i) { tree elt, basetype; TREE_VEC_ELT (bases, i) = elt = tsubst (TREE_VEC_ELT (pbases, i), args, NULL_TREE); BINFO_INHERITANCE_CHAIN (elt) = binfo; basetype = TREE_TYPE (elt); if (! IS_AGGR_TYPE (basetype)) cp_error ("base type `%T' of `%T' fails to be a struct or class type", basetype, type); else if (TYPE_SIZE (complete_type (basetype)) == NULL_TREE) cp_error ("base class `%T' of `%T' has incomplete type", basetype, type); /* These are set up in xref_basetypes for normal classes, so we have to handle them here for template bases. */ unshare_base_binfos (elt); if (TYPE_USES_VIRTUAL_BASECLASSES (basetype)) { TYPE_USES_VIRTUAL_BASECLASSES (type) = 1; TYPE_USES_COMPLEX_INHERITANCE (type) = 1; } TYPE_GETS_NEW (type) |= TYPE_GETS_NEW (basetype); TYPE_GETS_DELETE (type) |= TYPE_GETS_DELETE (basetype); } /* Don't initialize this until the vector is filled out, or lookups will crash. */ BINFO_BASETYPES (binfo) = bases; } } for (t = CLASSTYPE_TAGS (pattern); t; t = TREE_CHAIN (t)) { tree tag = TREE_VALUE (t); tree name = TYPE_IDENTIFIER (tag); tree newtag; newtag = tsubst (tag, args, NULL_TREE); if (TREE_CODE (newtag) != ENUMERAL_TYPE) { if (TYPE_LANG_SPECIFIC (tag) && CLASSTYPE_IS_TEMPLATE (tag)) /* Unfortunately, lookup_template_class sets CLASSTYPE_IMPLICIT_INSTANTIATION for a partial instantiation (i.e., for the type of a member template class nested within a template class.) This behavior is required for maybe_process_partial_specialization to work correctly, but is not accurate in this case; the TAG is not an instantiation of anything. (The corresponding TEMPLATE_DECL is an instantiation, but the TYPE is not.) */ CLASSTYPE_USE_TEMPLATE (newtag) = 0; /* Now, we call pushtag to put this NEWTAG into the scope of TYPE. We first set up the IDENTIFIER_TYPE_VALUE to avoid pushtag calling push_template_decl. We don't have to do this for enums because it will already have been done in tsubst_enum. */ if (name) SET_IDENTIFIER_TYPE_VALUE (name, newtag); pushtag (name, newtag, /*globalize=*/0); } } /* Don't replace enum constants here. */ for (t = TYPE_FIELDS (pattern); t; t = TREE_CHAIN (t)) if (TREE_CODE (t) != CONST_DECL) { tree r; /* The the file and line for this declaration, to assist in error message reporting. Since we called push_tinst_level above, we don't need to restore these. */ lineno = DECL_SOURCE_LINE (t); input_filename = DECL_SOURCE_FILE (t); r = tsubst (t, args, NULL_TREE); if (TREE_CODE (r) == VAR_DECL) { pending_statics = perm_tree_cons (NULL_TREE, r, pending_statics); /* Perhaps we should do more of grokfield here. */ start_decl_1 (r); DECL_IN_AGGR_P (r) = 1; DECL_EXTERNAL (r) = 1; cp_finish_decl (r, DECL_INITIAL (r), NULL_TREE, 0, 0); if (DECL_DEFINED_IN_CLASS_P (r)) check_static_variable_definition (r, TREE_TYPE (r)); } /* R will have a TREE_CHAIN if and only if it has already been processed by finish_member_declaration. This can happen if, for example, it is a TYPE_DECL for a class-scoped ENUMERAL_TYPE; such a thing will already have been added to the field list by tsubst_enum above. */ if (!TREE_CHAIN (r)) { set_current_access_from_decl (r); finish_member_declaration (r); } } /* Set up the list (TYPE_METHODS) and vector (CLASSTYPE_METHOD_VEC) for this instantiation. */ for (t = TYPE_METHODS (pattern); t; t = TREE_CHAIN (t)) { tree r = tsubst (t, args, NULL_TREE); set_current_access_from_decl (r); finish_member_declaration (r); } /* Construct the DECL_FRIENDLIST for the new class type. */ typedecl = TYPE_MAIN_DECL (type); for (t = DECL_FRIENDLIST (TYPE_MAIN_DECL (pattern)); t != NULL_TREE; t = TREE_CHAIN (t)) { tree friends; DECL_FRIENDLIST (typedecl) = tree_cons (TREE_PURPOSE (t), NULL_TREE, DECL_FRIENDLIST (typedecl)); for (friends = TREE_VALUE (t); friends != NULL_TREE; friends = TREE_CHAIN (friends)) { if (TREE_PURPOSE (friends) == error_mark_node) { TREE_VALUE (DECL_FRIENDLIST (typedecl)) = tree_cons (error_mark_node, tsubst_friend_function (TREE_VALUE (friends), args), TREE_VALUE (DECL_FRIENDLIST (typedecl))); } else { TREE_VALUE (DECL_FRIENDLIST (typedecl)) = tree_cons (tsubst (TREE_PURPOSE (friends), args, NULL_TREE), NULL_TREE, TREE_VALUE (DECL_FRIENDLIST (typedecl))); } } } for (t = CLASSTYPE_FRIEND_CLASSES (pattern); t != NULL_TREE; t = TREE_CHAIN (t)) { tree friend_type = TREE_VALUE (t); tree new_friend_type; if (TREE_CODE (friend_type) == TEMPLATE_DECL) new_friend_type = tsubst_friend_class (friend_type, args); else if (uses_template_parms (friend_type)) new_friend_type = tsubst (friend_type, args, NULL_TREE); else /* The call to xref_tag_from_type does injection for friend classes. */ new_friend_type = xref_tag_from_type (friend_type, NULL_TREE, 1); if (TREE_CODE (friend_type) == TEMPLATE_DECL) /* Trick make_friend_class into realizing that the friend we're adding is a template, not an ordinary class. It's important that we use make_friend_class since it will perform some error-checking and output cross-reference information. */ ++processing_template_decl; make_friend_class (type, new_friend_type); if (TREE_CODE (friend_type) == TEMPLATE_DECL) --processing_template_decl; } /* This does injection for friend functions. */ if (!processing_template_decl) { t = tsubst (DECL_TEMPLATE_INJECT (template), args, NULL_TREE); for (; t; t = TREE_CHAIN (t)) { tree d = TREE_VALUE (t); if (TREE_CODE (d) == TYPE_DECL) /* Already injected. */; else pushdecl (d); } } for (t = TYPE_FIELDS (type); t; t = TREE_CHAIN (t)) if (TREE_CODE (t) == FIELD_DECL) { TREE_TYPE (t) = complete_type (TREE_TYPE (t)); require_complete_type (t); } /* Set the file and line number information to whatever is given for the class itself. This puts error messages involving generated implicit functions at a predictable point, and the same point that would be used for non-template classes. */ lineno = DECL_SOURCE_LINE (typedecl); input_filename = DECL_SOURCE_FILE (typedecl); unreverse_member_declarations (type); type = finish_struct_1 (type, 0); CLASSTYPE_GOT_SEMICOLON (type) = 1; /* Clear this now so repo_template_used is happy. */ TYPE_BEING_DEFINED (type) = 0; repo_template_used (type); done_with_instantiation: TYPE_BEING_DEFINED (type) = 0; popclass (0); pop_from_top_level (); pop_tinst_level (); end: pop_momentary (); return type; } static int list_eq (t1, t2) tree t1, t2; { if (t1 == NULL_TREE) return t2 == NULL_TREE; if (t2 == NULL_TREE) return 0; /* Don't care if one declares its arg const and the other doesn't -- the main variant of the arg type is all that matters. */ if (TYPE_MAIN_VARIANT (TREE_VALUE (t1)) != TYPE_MAIN_VARIANT (TREE_VALUE (t2))) return 0; return list_eq (TREE_CHAIN (t1), TREE_CHAIN (t2)); } /* If arg is a non-type template parameter that does not depend on template arguments, fold it like we weren't in the body of a template. */ static tree maybe_fold_nontype_arg (arg) tree arg; { if (TREE_CODE_CLASS (TREE_CODE (arg)) != 't' && !uses_template_parms (arg)) { /* Sometimes, one of the args was an expression involving a template constant parameter, like N - 1. Now that we've tsubst'd, we might have something like 2 - 1. This will confuse lookup_template_class, so we do constant folding here. We have to unset processing_template_decl, to fool build_expr_from_tree() into building an actual tree. */ int saved_processing_template_decl = processing_template_decl; processing_template_decl = 0; arg = fold (build_expr_from_tree (arg)); processing_template_decl = saved_processing_template_decl; } return arg; } /* Return the TREE_VEC with the arguments for the innermost template header, where ARGS is either that or the VEC of VECs for all the arguments. */ tree innermost_args (args) tree args; { return TMPL_ARGS_LEVEL (args, TMPL_ARGS_DEPTH (args)); } /* Substitute ARGS into the vector of template arguments T. */ tree tsubst_template_arg_vector (t, args) tree t; tree args; { int len = TREE_VEC_LENGTH (t), need_new = 0, i; tree *elts = (tree *) alloca (len * sizeof (tree)); bzero ((char *) elts, len * sizeof (tree)); for (i = 0; i < len; i++) { if (TREE_VEC_ELT (t, i) != NULL_TREE && TREE_CODE (TREE_VEC_ELT (t, i)) == TREE_VEC) elts[i] = tsubst_template_arg_vector (TREE_VEC_ELT (t, i), args); else elts[i] = maybe_fold_nontype_arg (tsubst_expr (TREE_VEC_ELT (t, i), args, NULL_TREE)); if (elts[i] != TREE_VEC_ELT (t, i)) need_new = 1; } if (!need_new) return t; t = make_temp_vec (len); for (i = 0; i < len; i++) TREE_VEC_ELT (t, i) = elts[i]; return t; } /* Return the result of substituting ARGS into the template parameters given by PARMS. If there are m levels of ARGS and m + n levels of PARMS, then the result will contain n levels of PARMS. For example, if PARMS is `template <class T> template <class U> template <T*, U, class V>' and ARGS is {{int}, {double}} then the result will be `template <int*, double, class V>'. */ tree tsubst_template_parms (parms, args) tree parms; tree args; { tree r; tree* new_parms = &r; for (new_parms = &r; TMPL_PARMS_DEPTH (parms) > TMPL_ARGS_DEPTH (args); new_parms = &(TREE_CHAIN (*new_parms)), parms = TREE_CHAIN (parms)) { tree new_vec = make_tree_vec (TREE_VEC_LENGTH (TREE_VALUE (parms))); int i; for (i = 0; i < TREE_VEC_LENGTH (new_vec); ++i) { tree default_value = TREE_PURPOSE (TREE_VEC_ELT (TREE_VALUE (parms), i)); tree parm_decl = TREE_VALUE (TREE_VEC_ELT (TREE_VALUE (parms), i)); TREE_VEC_ELT (new_vec, i) = build_tree_list (tsubst (default_value, args, NULL_TREE), tsubst (parm_decl, args, NULL_TREE)); } *new_parms = tree_cons (build_int_2 (0, (TMPL_PARMS_DEPTH (parms) - TMPL_ARGS_DEPTH (args))), new_vec, NULL_TREE); } return r; } /* Substitute the ARGS into the indicated aggregate (or enumeration) type T. If T is not an aggregate or enumeration type, it is handled as if by tsubst. IN_DECL is as for tsubst. If ENTERING_SCOPE is non-zero, T is the context for a template which we are presently tsubst'ing. Return the subsituted value. */ tree tsubst_aggr_type (t, args, in_decl, entering_scope) tree t; tree args; tree in_decl; int entering_scope; { if (t == NULL_TREE) return NULL_TREE; switch (TREE_CODE (t)) { case RECORD_TYPE: if (TYPE_PTRMEMFUNC_P (t)) { tree r = build_ptrmemfunc_type (tsubst (TYPE_PTRMEMFUNC_FN_TYPE (t), args, in_decl)); return cp_build_qualified_type (r, TYPE_QUALS (t)); } /* else fall through */ case ENUMERAL_TYPE: case UNION_TYPE: if (uses_template_parms (t)) { tree argvec; tree context; tree r; /* First, determine the context for the type we are looking up. */ if (TYPE_CONTEXT (t) != NULL_TREE) context = tsubst_aggr_type (TYPE_CONTEXT (t), args, in_decl, /*entering_scope=*/1); else context = NULL_TREE; /* Then, figure out what arguments are appropriate for the type we are trying to find. For example, given: template <class T> struct S; template <class T, class U> void f(T, U) { S<U> su; } and supposing that we are instantiating f<int, double>, then our ARGS will be {int, double}, but, when looking up S we only want {double}. */ push_momentary (); argvec = tsubst_template_arg_vector (TYPE_TI_ARGS (t), args); r = lookup_template_class (t, argvec, in_decl, context, entering_scope); pop_momentary (); return cp_build_qualified_type (r, TYPE_QUALS (t)); } else /* This is not a template type, so there's nothing to do. */ return t; default: return tsubst (t, args, in_decl); } } /* Substitute the ARGS into the T, which is a _DECL. TYPE is the (already computed) substitution of ARGS into TREE_TYPE (T), if appropriate. Return the result of the substitution. IN_DECL is as for tsubst. */ tree tsubst_decl (t, args, type, in_decl) tree t; tree args; tree type; tree in_decl; { int saved_lineno; char* saved_filename; tree r = NULL_TREE; /* Set the filename and linenumber to improve error-reporting. */ saved_lineno = lineno; saved_filename = input_filename; lineno = DECL_SOURCE_LINE (t); input_filename = DECL_SOURCE_FILE (t); switch (TREE_CODE (t)) { case TEMPLATE_DECL: { /* We can get here when processing a member template function of a template class. */ tree decl = DECL_TEMPLATE_RESULT (t); tree spec; int is_template_template_parm = DECL_TEMPLATE_TEMPLATE_PARM_P (t); if (!is_template_template_parm) { /* We might already have an instance of this template. The ARGS are for the surrounding class type, so the full args contain the tsubst'd args for the context, plus the innermost args from the template decl. */ tree tmpl_args = DECL_CLASS_TEMPLATE_P (t) ? CLASSTYPE_TI_ARGS (TREE_TYPE (t)) : DECL_TI_ARGS (DECL_RESULT (t)); tree full_args; push_momentary (); full_args = tsubst_template_arg_vector (tmpl_args, args); /* tsubst_template_arg_vector doesn't copy the vector if nothing changed. But, *something* should have changed. */ my_friendly_assert (full_args != tmpl_args, 0); spec = retrieve_specialization (t, full_args); pop_momentary (); if (spec != NULL_TREE) { r = spec; break; } } /* Make a new template decl. It will be similar to the original, but will record the current template arguments. We also create a new function declaration, which is just like the old one, but points to this new template, rather than the old one. */ r = copy_node (t); copy_lang_decl (r); my_friendly_assert (DECL_LANG_SPECIFIC (r) != 0, 0); TREE_CHAIN (r) = NULL_TREE; if (is_template_template_parm) { tree new_decl = tsubst (decl, args, in_decl); DECL_RESULT (r) = new_decl; TREE_TYPE (r) = TREE_TYPE (new_decl); break; } DECL_CONTEXT (r) = tsubst_aggr_type (DECL_CONTEXT (t), args, in_decl, /*entering_scope=*/1); DECL_CLASS_CONTEXT (r) = tsubst_aggr_type (DECL_CLASS_CONTEXT (t), args, in_decl, /*entering_scope=*/1); DECL_TEMPLATE_INFO (r) = build_tree_list (t, args); if (TREE_CODE (decl) == TYPE_DECL) { tree new_type = tsubst (TREE_TYPE (t), args, in_decl); TREE_TYPE (r) = new_type; CLASSTYPE_TI_TEMPLATE (new_type) = r; DECL_RESULT (r) = TYPE_MAIN_DECL (new_type); DECL_TI_ARGS (r) = CLASSTYPE_TI_ARGS (new_type); } else { tree new_decl = tsubst (decl, args, in_decl); DECL_RESULT (r) = new_decl; DECL_TI_TEMPLATE (new_decl) = r; TREE_TYPE (r) = TREE_TYPE (new_decl); DECL_TI_ARGS (r) = DECL_TI_ARGS (new_decl); } SET_DECL_IMPLICIT_INSTANTIATION (r); DECL_TEMPLATE_INSTANTIATIONS (r) = NULL_TREE; DECL_TEMPLATE_SPECIALIZATIONS (r) = NULL_TREE; /* The template parameters for this new template are all the template parameters for the old template, except the outermost level of parameters. */ DECL_TEMPLATE_PARMS (r) = tsubst_template_parms (DECL_TEMPLATE_PARMS (t), args); if (PRIMARY_TEMPLATE_P (t)) DECL_PRIMARY_TEMPLATE (r) = r; /* We don't partially instantiate partial specializations. */ if (TREE_CODE (decl) == TYPE_DECL) break; for (spec = DECL_TEMPLATE_SPECIALIZATIONS (t); spec != NULL_TREE; spec = TREE_CHAIN (spec)) { /* It helps to consider example here. Consider: template <class T> struct S { template <class U> void f(U u); template <> void f(T* t) {} }; Now, for example, we are instantiating S<int>::f(U u). We want to make a template: template <class U> void S<int>::f(U); It will have a specialization, for the case U = int*, of the form: template <> void S<int>::f<int*>(int*); This specialization will be an instantiation of the specialization given in the declaration of S, with argument list int*. */ tree fn = TREE_VALUE (spec); tree spec_args; tree new_fn; if (!DECL_TEMPLATE_SPECIALIZATION (fn)) /* Instantiations are on the same list, but they're of no concern to us. */ continue; if (TREE_CODE (fn) != TEMPLATE_DECL) /* A full specialization. There's no need to record that here. */ continue; spec_args = tsubst (DECL_TI_ARGS (fn), args, in_decl); new_fn = tsubst (DECL_RESULT (most_general_template (fn)), spec_args, in_decl); DECL_TI_TEMPLATE (new_fn) = fn; register_specialization (new_fn, r, innermost_args (spec_args)); } /* Record this partial instantiation. */ register_specialization (r, t, DECL_TI_ARGS (DECL_RESULT (r))); } break; case FUNCTION_DECL: { tree ctx; tree argvec = NULL_TREE; tree gen_tmpl; int member; int args_depth; int parms_depth; /* Nobody should be tsubst'ing into non-template functions. */ my_friendly_assert (DECL_TEMPLATE_INFO (t) != NULL_TREE, 0); if (TREE_CODE (DECL_TI_TEMPLATE (t)) == TEMPLATE_DECL) { tree spec; /* Allocate template arguments on the momentary obstack, in case we don't need to keep them. */ push_momentary (); /* Calculate the most general template of which R is a specialization, and the complete set of arguments used to specialize R. */ gen_tmpl = most_general_template (DECL_TI_TEMPLATE (t)); argvec = tsubst_template_arg_vector (DECL_TI_ARGS (DECL_TEMPLATE_RESULT (gen_tmpl)), args); /* Check to see if we already have this specialization. */ spec = retrieve_specialization (gen_tmpl, argvec); if (spec) { r = spec; pop_momentary (); break; } /* We're going to need to keep the ARGVEC, so we copy it here. */ argvec = copy_to_permanent (argvec); pop_momentary (); /* Here, we deal with the peculiar case: template <class T> struct S { template <class U> friend void f(); }; template <class U> friend void f() {} template S<int>; template void f<double>(); Here, the ARGS for the instantiation of will be {int, double}. But, we only need as many ARGS as there are levels of template parameters in CODE_PATTERN. We are careful not to get fooled into reducing the ARGS in situations like: template <class T> struct S { template <class U> void f(U); } template <class T> template <> void S<T>::f(int) {} which we can spot because the pattern will be a specialization in this case. */ args_depth = TMPL_ARGS_DEPTH (args); parms_depth = TMPL_PARMS_DEPTH (DECL_TEMPLATE_PARMS (DECL_TI_TEMPLATE (t))); if (args_depth > parms_depth && !DECL_TEMPLATE_SPECIALIZATION (t)) { my_friendly_assert (DECL_FRIEND_P (t), 0); if (parms_depth > 1) { int i; args = make_temp_vec (parms_depth); for (i = 0; i < parms_depth; ++i) TREE_VEC_ELT (args, i) = TREE_VEC_ELT (args, i + (args_depth - parms_depth)); } else args = TREE_VEC_ELT (args, args_depth - parms_depth); } } else { /* This special case arises when we have something like this: template <class T> struct S { friend void f<int>(int, double); }; Here, the DECL_TI_TEMPLATE for the friend declaration will be a LOOKUP_EXPR or an IDENTIFIER_NODE. We are being called from tsubst_friend_function, and we want only to create a new decl (R) with appropriate types so that we can call determine_specialization. */ my_friendly_assert ((TREE_CODE (DECL_TI_TEMPLATE (t)) == LOOKUP_EXPR) || (TREE_CODE (DECL_TI_TEMPLATE (t)) == IDENTIFIER_NODE), 0); gen_tmpl = NULL_TREE; } if (DECL_CLASS_SCOPE_P (t)) { if (DECL_NAME (t) == constructor_name (DECL_CONTEXT (t))) member = 2; else member = 1; ctx = tsubst_aggr_type (DECL_CLASS_CONTEXT (t), args, t, /*entering_scope=*/1); } else { member = 0; ctx = NULL_TREE; } type = tsubst (type, args, in_decl); /* We do NOT check for matching decls pushed separately at this point, as they may not represent instantiations of this template, and in any case are considered separate under the discrete model. Instead, see add_maybe_template. */ r = copy_node (t); copy_lang_decl (r); DECL_USE_TEMPLATE (r) = 0; TREE_TYPE (r) = type; DECL_CONTEXT (r) = tsubst_aggr_type (DECL_CONTEXT (t), args, t, /*entering_scope=*/1); DECL_CLASS_CONTEXT (r) = ctx; if (member && !strncmp (OPERATOR_TYPENAME_FORMAT, IDENTIFIER_POINTER (DECL_NAME (r)), sizeof (OPERATOR_TYPENAME_FORMAT) - 1)) { /* Type-conversion operator. Reconstruct the name, in case it's the name of one of the template's parameters. */ DECL_NAME (r) = build_typename_overload (TREE_TYPE (type)); } DECL_ARGUMENTS (r) = tsubst (DECL_ARGUMENTS (t), args, t); DECL_MAIN_VARIANT (r) = r; DECL_RESULT (r) = NULL_TREE; TREE_STATIC (r) = 0; TREE_PUBLIC (r) = TREE_PUBLIC (t); DECL_EXTERNAL (r) = 1; DECL_INTERFACE_KNOWN (r) = 0; DECL_DEFER_OUTPUT (r) = 0; TREE_CHAIN (r) = NULL_TREE; DECL_PENDING_INLINE_INFO (r) = 0; TREE_USED (r) = 0; if (DECL_CONSTRUCTOR_P (r)) { maybe_retrofit_in_chrg (r); grok_ctor_properties (ctx, r); } if (IDENTIFIER_OPNAME_P (DECL_NAME (r))) grok_op_properties (r, DECL_VIRTUAL_P (r), DECL_FRIEND_P (r)); /* Set up the DECL_TEMPLATE_INFO for R and compute its mangled name. There's no need to do this in the special friend case mentioned above where GEN_TMPL is NULL. */ if (gen_tmpl) { /* The ARGVEC was built on the momentary obstack. Make it permanent now. */ argvec = copy_to_permanent (argvec); DECL_TEMPLATE_INFO (r) = perm_tree_cons (gen_tmpl, argvec, NULL_TREE); SET_DECL_IMPLICIT_INSTANTIATION (r); register_specialization (r, gen_tmpl, argvec); /* Set the mangled name for R. */ if (DECL_DESTRUCTOR_P (t)) DECL_ASSEMBLER_NAME (r) = build_destructor_name (ctx); else { /* Instantiations of template functions must be mangled specially, in order to conform to 14.5.5.1 [temp.over.link]. */ tree tmpl = DECL_TI_TEMPLATE (t); /* TMPL will be NULL if this is a specialization of a member function of a template class. */ if (name_mangling_version < 1 || tmpl == NULL_TREE || (member && !is_member_template (tmpl) && !DECL_TEMPLATE_INFO (tmpl))) set_mangled_name_for_decl (r); else set_mangled_name_for_template_decl (r); } DECL_RTL (r) = 0; make_decl_rtl (r, NULL_PTR, 1); /* Like grokfndecl. If we don't do this, pushdecl will mess up our TREE_CHAIN because it doesn't find a previous decl. Sigh. */ if (member && ! uses_template_parms (r) && (IDENTIFIER_GLOBAL_VALUE (DECL_ASSEMBLER_NAME (r)) == NULL_TREE)) SET_IDENTIFIER_GLOBAL_VALUE (DECL_ASSEMBLER_NAME (r), r); } } break; case PARM_DECL: { r = copy_node (t); TREE_TYPE (r) = type; if (TREE_CODE (DECL_INITIAL (r)) != TEMPLATE_PARM_INDEX) DECL_INITIAL (r) = TREE_TYPE (r); else DECL_INITIAL (r) = tsubst (DECL_INITIAL (r), args, in_decl); DECL_CONTEXT (r) = NULL_TREE; #ifdef PROMOTE_PROTOTYPES if ((TREE_CODE (type) == INTEGER_TYPE || TREE_CODE (type) == ENUMERAL_TYPE) && TYPE_PRECISION (type) < TYPE_PRECISION (integer_type_node)) DECL_ARG_TYPE (r) = integer_type_node; #endif if (TREE_CHAIN (t)) TREE_CHAIN (r) = tsubst (TREE_CHAIN (t), args, TREE_CHAIN (t)); } break; case FIELD_DECL: { r = copy_node (t); TREE_TYPE (r) = type; copy_lang_decl (r); #if 0 DECL_FIELD_CONTEXT (r) = tsubst (DECL_FIELD_CONTEXT (t), args, in_decl); #endif DECL_INITIAL (r) = tsubst_expr (DECL_INITIAL (t), args, in_decl); TREE_CHAIN (r) = NULL_TREE; if (TREE_CODE (type) == VOID_TYPE) cp_error_at ("instantiation of `%D' as type void", r); } break; case USING_DECL: { r = copy_node (t); DECL_INITIAL (r) = tsubst_copy (DECL_INITIAL (t), args, in_decl); TREE_CHAIN (r) = NULL_TREE; } break; case VAR_DECL: { tree argvec; tree gen_tmpl; tree spec; tree tmpl; tree ctx = tsubst_aggr_type (DECL_CONTEXT (t), args, in_decl, /*entering_scope=*/1); /* Nobody should be tsubst'ing into non-template variables. */ my_friendly_assert (DECL_LANG_SPECIFIC (t) && DECL_TEMPLATE_INFO (t) != NULL_TREE, 0); /* Check to see if we already have this specialization. */ tmpl = DECL_TI_TEMPLATE (t); gen_tmpl = most_general_template (tmpl); argvec = tsubst (DECL_TI_ARGS (t), args, in_decl); spec = retrieve_specialization (gen_tmpl, argvec); if (spec) { r = spec; break; } r = copy_node (t); TREE_TYPE (r) = type; DECL_CONTEXT (r) = ctx; if (TREE_STATIC (r)) DECL_ASSEMBLER_NAME (r) = build_static_name (DECL_CONTEXT (r), DECL_NAME (r)); /* Don't try to expand the initializer until someone tries to use this variable; otherwise we run into circular dependencies. */ DECL_INITIAL (r) = NULL_TREE; DECL_RTL (r) = 0; DECL_SIZE (r) = 0; copy_lang_decl (r); DECL_CLASS_CONTEXT (r) = DECL_CONTEXT (r); DECL_TEMPLATE_INFO (r) = perm_tree_cons (tmpl, argvec, NULL_TREE); SET_DECL_IMPLICIT_INSTANTIATION (r); register_specialization (r, gen_tmpl, argvec); TREE_CHAIN (r) = NULL_TREE; if (TREE_CODE (type) == VOID_TYPE) cp_error_at ("instantiation of `%D' as type void", r); } break; case TYPE_DECL: if (t == TYPE_NAME (TREE_TYPE (t))) r = TYPE_NAME (type); else { r = copy_node (t); TREE_TYPE (r) = type; DECL_CONTEXT (r) = current_class_type; TREE_CHAIN (r) = NULL_TREE; } break; default: my_friendly_abort (0); } /* Restore the file and line information. */ lineno = saved_lineno; input_filename = saved_filename; return r; } /* Substitue into the ARG_TYPES of a function type. */ tree tsubst_arg_types (arg_types, args, in_decl) tree arg_types; tree args; tree in_decl; { tree remaining_arg_types; tree type; if (!arg_types || arg_types == void_list_node) return arg_types; remaining_arg_types = tsubst_arg_types (TREE_CHAIN (arg_types), args, in_decl); /* We use TYPE_MAIN_VARIANT is because top-level qualifiers don't matter on function types. */ type = TYPE_MAIN_VARIANT (type_decays_to (tsubst (TREE_VALUE (arg_types), args, in_decl))); /* Note that we do not substitute into default arguments here. The standard mandates that they be instantiated only when needed, which is done in build_over_call. */ return hash_tree_cons_simple (TREE_PURPOSE (arg_types), type, remaining_arg_types); } /* Take the tree structure T and replace template parameters used therein with the argument vector ARGS. IN_DECL is an associated decl for diagnostics. tsubst is used for dealing with types, decls and the like; for expressions, use tsubst_expr or tsubst_copy. */ tree tsubst (t, args, in_decl) tree t, args; tree in_decl; { tree type, r; if (t == NULL_TREE || t == error_mark_node || t == integer_type_node || t == void_type_node || t == char_type_node || TREE_CODE (t) == NAMESPACE_DECL) return t; if (TREE_CODE (t) == IDENTIFIER_NODE) type = IDENTIFIER_TYPE_VALUE (t); else type = TREE_TYPE (t); if (type == unknown_type_node) my_friendly_abort (42); if (type && TREE_CODE (t) != FUNCTION_DECL && TREE_CODE (t) != TYPENAME_TYPE && TREE_CODE (t) != TEMPLATE_DECL && TREE_CODE (t) != IDENTIFIER_NODE) type = tsubst (type, args, in_decl); if (TREE_CODE_CLASS (TREE_CODE (t)) == 'd') return tsubst_decl (t, args, type, in_decl); switch (TREE_CODE (t)) { case RECORD_TYPE: case UNION_TYPE: case ENUMERAL_TYPE: return tsubst_aggr_type (t, args, in_decl, /*entering_scope=*/0); case ERROR_MARK: case IDENTIFIER_NODE: case OP_IDENTIFIER: case VOID_TYPE: case REAL_TYPE: case COMPLEX_TYPE: case BOOLEAN_TYPE: case INTEGER_CST: case REAL_CST: case STRING_CST: return t; case INTEGER_TYPE: if (t == integer_type_node) return t; if (TREE_CODE (TYPE_MIN_VALUE (t)) == INTEGER_CST && TREE_CODE (TYPE_MAX_VALUE (t)) == INTEGER_CST) return t; { tree max = TREE_OPERAND (TYPE_MAX_VALUE (t), 0); max = tsubst_expr (max, args, in_decl); if (processing_template_decl) { tree itype = make_node (INTEGER_TYPE); TYPE_MIN_VALUE (itype) = size_zero_node; TYPE_MAX_VALUE (itype) = build_min (MINUS_EXPR, sizetype, max, integer_one_node); return itype; } if (pedantic && integer_zerop (max)) pedwarn ("creating array with size zero"); else if (INT_CST_LT (max, integer_zero_node)) { cp_error ("creating array with size `%E'", max); max = integer_one_node; } max = fold (build_binary_op (MINUS_EXPR, max, integer_one_node, 1)); if (!TREE_PERMANENT (max) && !allocation_temporary_p ()) max = copy_to_permanent (max); return build_index_type (max); } case TEMPLATE_TYPE_PARM: case TEMPLATE_TEMPLATE_PARM: case TEMPLATE_PARM_INDEX: { int idx; int level; int levels; r = NULL_TREE; if (TREE_CODE (t) == TEMPLATE_TYPE_PARM || TREE_CODE (t) == TEMPLATE_TEMPLATE_PARM) { idx = TEMPLATE_TYPE_IDX (t); level = TEMPLATE_TYPE_LEVEL (t); } else { idx = TEMPLATE_PARM_IDX (t); level = TEMPLATE_PARM_LEVEL (t); } if (TREE_VEC_LENGTH (args) > 0) { tree arg = NULL_TREE; levels = TMPL_ARGS_DEPTH (args); if (level <= levels) arg = TMPL_ARG (args, level, idx); if (arg == error_mark_node) return error_mark_node; else if (arg != NULL_TREE) { if (TREE_CODE (t) == TEMPLATE_TYPE_PARM) { my_friendly_assert (TREE_CODE_CLASS (TREE_CODE (arg)) == 't', 0); return cp_build_qualified_type (arg, CP_TYPE_QUALS (arg) | CP_TYPE_QUALS (t)); } else if (TREE_CODE (t) == TEMPLATE_TEMPLATE_PARM) { if (TEMPLATE_TEMPLATE_PARM_TEMPLATE_INFO (t)) { /* We are processing a type constructed from a template template parameter */ tree argvec = tsubst (TYPE_TI_ARGS (t), args, in_decl); /* We can get a TEMPLATE_TEMPLATE_PARM here when we are resolving nested-types in the signature of a member function templates. Otherwise ARG is a TEMPLATE_DECL and is the real template to be instantiated. */ if (TREE_CODE (arg) == TEMPLATE_TEMPLATE_PARM) arg = TYPE_NAME (arg); r = lookup_template_class (DECL_NAME (arg), argvec, in_decl, DECL_CONTEXT (arg), /*entering_scope=*/0); return cp_build_qualified_type (r, TYPE_QUALS (t)); } else /* We are processing a template argument list. */ return arg; } else return arg; } } else my_friendly_abort (981018); if (level == 1) /* This can happen during the attempted tsubst'ing in unify. This means that we don't yet have any information about the template parameter in question. */ return t; /* If we get here, we must have been looking at a parm for a more deeply nested template. Make a new version of this template parameter, but with a lower level. */ switch (TREE_CODE (t)) { case TEMPLATE_TYPE_PARM: case TEMPLATE_TEMPLATE_PARM: r = copy_node (t); TEMPLATE_TYPE_PARM_INDEX (r) = reduce_template_parm_level (TEMPLATE_TYPE_PARM_INDEX (t), r, levels); TYPE_STUB_DECL (r) = TYPE_NAME (r) = TEMPLATE_TYPE_DECL (r); TYPE_MAIN_VARIANT (r) = r; TYPE_POINTER_TO (r) = NULL_TREE; TYPE_REFERENCE_TO (r) = NULL_TREE; if (TREE_CODE (t) == TEMPLATE_TEMPLATE_PARM && TEMPLATE_TEMPLATE_PARM_TEMPLATE_INFO (t)) { tree argvec = tsubst (TYPE_TI_ARGS (t), args, in_decl); TEMPLATE_TEMPLATE_PARM_TEMPLATE_INFO (r) = perm_tree_cons (TYPE_NAME (t), argvec, NULL_TREE); } break; case TEMPLATE_PARM_INDEX: r = reduce_template_parm_level (t, type, levels); break; default: my_friendly_abort (0); } return r; } case TREE_LIST: { tree purpose, value, chain, result; int via_public, via_virtual, via_protected; if (t == void_list_node) return t; via_public = TREE_VIA_PUBLIC (t); via_protected = TREE_VIA_PROTECTED (t); via_virtual = TREE_VIA_VIRTUAL (t); purpose = TREE_PURPOSE (t); if (purpose) purpose = tsubst (purpose, args, in_decl); value = TREE_VALUE (t); if (value) value = tsubst (value, args, in_decl); chain = TREE_CHAIN (t); if (chain && chain != void_type_node) chain = tsubst (chain, args, in_decl); if (purpose == TREE_PURPOSE (t) && value == TREE_VALUE (t) && chain == TREE_CHAIN (t)) return t; result = hash_tree_cons (via_public, via_virtual, via_protected, purpose, value, chain); TREE_PARMLIST (result) = TREE_PARMLIST (t); return result; } case TREE_VEC: if (type != NULL_TREE) { /* A binfo node. We always need to make a copy, of the node itself and of its BINFO_BASETYPES. */ t = copy_node (t); /* Make sure type isn't a typedef copy. */ type = BINFO_TYPE (TYPE_BINFO (type)); TREE_TYPE (t) = complete_type (type); if (IS_AGGR_TYPE (type)) { BINFO_VTABLE (t) = TYPE_BINFO_VTABLE (type); BINFO_VIRTUALS (t) = TYPE_BINFO_VIRTUALS (type); if (TYPE_BINFO_BASETYPES (type) != NULL_TREE) BINFO_BASETYPES (t) = copy_node (TYPE_BINFO_BASETYPES (type)); } return t; } /* Otherwise, a vector of template arguments. */ return tsubst_template_arg_vector (t, args); case POINTER_TYPE: case REFERENCE_TYPE: { enum tree_code code; if (type == TREE_TYPE (t)) return t; code = TREE_CODE (t); if (TREE_CODE (type) == REFERENCE_TYPE || (code == REFERENCE_TYPE && TREE_CODE (type) == VOID_TYPE)) { static int last_line = 0; static char* last_file = 0; /* We keep track of the last time we issued this error message to avoid spewing a ton of messages during a single bad template instantiation. */ if (last_line != lineno || last_file != input_filename) { if (TREE_CODE (type) == VOID_TYPE) cp_error ("forming reference to void"); else cp_error ("forming %s to reference type `%T'", (code == POINTER_TYPE) ? "pointer" : "reference", type); last_line = lineno; last_file = input_filename; } /* Use the underlying type in an attempt at error recovery; maybe the user meant vector<int> and wrote vector<int&>, or some such. */ if (code == REFERENCE_TYPE) r = type; else r = build_pointer_type (TREE_TYPE (type)); } else if (code == POINTER_TYPE) r = build_pointer_type (type); else r = build_reference_type (type); r = cp_build_qualified_type (r, TYPE_QUALS (t)); /* Will this ever be needed for TYPE_..._TO values? */ layout_type (r); return r; } case OFFSET_TYPE: { r = tsubst (TYPE_OFFSET_BASETYPE (t), args, in_decl); if (! IS_AGGR_TYPE (r)) cp_error ("creating pointer to member of non-class type `%T'", r); return build_offset_type (r, type); } case FUNCTION_TYPE: case METHOD_TYPE: { tree arg_types; tree raises; tree fntype; /* The TYPE_CONTEXT is not used for function/method types. */ my_friendly_assert (TYPE_CONTEXT (t) == NULL_TREE, 0); /* Substitue the argument types. */ arg_types = tsubst_arg_types (TYPE_ARG_TYPES (t), args, in_decl); /* Construct a new type node and return it. */ if (TREE_CODE (t) == FUNCTION_TYPE) fntype = build_function_type (type, arg_types); else { r = TREE_TYPE (TREE_VALUE (arg_types)); if (! IS_AGGR_TYPE (r)) cp_error ("creating pointer to member function of non-class type `%T'", r); fntype = build_cplus_method_type (r, type, TREE_CHAIN (arg_types)); } fntype = build_qualified_type (fntype, TYPE_QUALS (t)); /* Substitue the exception specification. */ raises = TYPE_RAISES_EXCEPTIONS (t); if (raises) { raises = tsubst (raises, args, in_decl); fntype = build_exception_variant (fntype, raises); } return fntype; } case ARRAY_TYPE: { tree domain = tsubst (TYPE_DOMAIN (t), args, in_decl); if (type == TREE_TYPE (t) && domain == TYPE_DOMAIN (t)) return t; /* These checks should match the ones in grokdeclarator. */ if (TREE_CODE (type) == VOID_TYPE) { cp_error ("creating array of void"); type = build_pointer_type (type); } else if (TREE_CODE (type) == FUNCTION_TYPE) { cp_error ("creating array of functions `%T'", type); type = build_pointer_type (type); } else if (TREE_CODE (type) == REFERENCE_TYPE) { cp_error ("creating array of references `%T'", type); type = TREE_TYPE (type); } r = build_cplus_array_type (type, domain); return r; } case PLUS_EXPR: case MINUS_EXPR: return fold (build (TREE_CODE (t), TREE_TYPE (t), tsubst (TREE_OPERAND (t, 0), args, in_decl), tsubst (TREE_OPERAND (t, 1), args, in_decl))); case NEGATE_EXPR: case NOP_EXPR: return fold (build1 (TREE_CODE (t), TREE_TYPE (t), tsubst (TREE_OPERAND (t, 0), args, in_decl))); case TYPENAME_TYPE: { tree ctx = tsubst_aggr_type (TYPE_CONTEXT (t), args, in_decl, /*entering_scope=*/1); tree f = tsubst_copy (TYPENAME_TYPE_FULLNAME (t), args, in_decl); /* Normally, make_typename_type does not require that the CTX have complete type in order to allow things like: template <class T> struct S { typename S<T>::X Y; }; But, such constructs have already been resolved by this point, so here CTX really should have complete type, unless it's a partial instantiation. */ if (!uses_template_parms (ctx) && !complete_type_or_else (ctx)) return error_mark_node; f = make_typename_type (ctx, f); return cp_build_qualified_type (f, CP_TYPE_QUALS (f) | CP_TYPE_QUALS (t)); } case INDIRECT_REF: return make_pointer_declarator (type, tsubst (TREE_OPERAND (t, 0), args, in_decl)); case ADDR_EXPR: return make_reference_declarator (type, tsubst (TREE_OPERAND (t, 0), args, in_decl)); case ARRAY_REF: return build_parse_node (ARRAY_REF, tsubst (TREE_OPERAND (t, 0), args, in_decl), tsubst_expr (TREE_OPERAND (t, 1), args, in_decl)); case CALL_EXPR: return make_call_declarator (tsubst (TREE_OPERAND (t, 0), args, in_decl), tsubst (TREE_OPERAND (t, 1), args, in_decl), TREE_OPERAND (t, 2), tsubst (TREE_TYPE (t), args, in_decl)); case SCOPE_REF: return build_parse_node (TREE_CODE (t), tsubst (TREE_OPERAND (t, 0), args, in_decl), tsubst (TREE_OPERAND (t, 1), args, in_decl)); case TYPEOF_TYPE: return TREE_TYPE (tsubst_expr (TYPE_FIELDS (t), args, in_decl)); default: sorry ("use of `%s' in template", tree_code_name [(int) TREE_CODE (t)]); return error_mark_node; } } void do_pushlevel () { emit_line_note (input_filename, lineno); pushlevel (0); clear_last_expr (); push_momentary (); expand_start_bindings (0); } tree do_poplevel () { tree t; int saved_warn_unused = 0; if (processing_template_decl) { saved_warn_unused = warn_unused; warn_unused = 0; } expand_end_bindings (getdecls (), kept_level_p (), 0); if (processing_template_decl) warn_unused = saved_warn_unused; t = poplevel (kept_level_p (), 1, 0); pop_momentary (); return t; } /* Like tsubst, but deals with expressions. This function just replaces template parms; to finish processing the resultant expression, use tsubst_expr. */ tree tsubst_copy (t, args, in_decl) tree t, args; tree in_decl; { enum tree_code code; tree r; if (t == NULL_TREE || t == error_mark_node) return t; code = TREE_CODE (t); switch (code) { case PARM_DECL: return do_identifier (DECL_NAME (t), 0, NULL_TREE); case CONST_DECL: { tree enum_type; tree v; if (!DECL_CONTEXT (t)) /* This is a global enumeration constant. */ return t; /* Unfortunately, we cannot just call lookup_name here. Consider: template <int I> int f() { enum E { a = I }; struct S { void g() { E e = a; } }; }; When we instantiate f<7>::S::g(), say, lookup_name is not clever enough to find f<7>::a. */ enum_type = tsubst_aggr_type (TREE_TYPE (t), args, in_decl, /*entering_scope=*/0); for (v = TYPE_VALUES (enum_type); v != NULL_TREE; v = TREE_CHAIN (v)) if (TREE_PURPOSE (v) == DECL_NAME (t)) return TREE_VALUE (v); /* We didn't find the name. That should never happen; if name-lookup found it during preliminary parsing, we should find it again here during instantiation. */ my_friendly_abort (0); } return t; case FIELD_DECL: if (DECL_CONTEXT (t)) { tree ctx; ctx = tsubst_aggr_type (DECL_CONTEXT (t), args, in_decl, /*entering_scope=*/1); if (ctx != DECL_CONTEXT (t)) return lookup_field (ctx, DECL_NAME (t), 0, 0); } return t; case VAR_DECL: case FUNCTION_DECL: if (DECL_LANG_SPECIFIC (t) && DECL_TEMPLATE_INFO (t)) t = tsubst (t, args, in_decl); mark_used (t); return t; case TEMPLATE_DECL: if (is_member_template (t)) return tsubst (t, args, in_decl); else return t; case LOOKUP_EXPR: { /* We must tsbust into a LOOKUP_EXPR in case the names to which it refers is a conversion operator; in that case the name will change. We avoid making unnecessary copies, however. */ tree id = tsubst_copy (TREE_OPERAND (t, 0), args, in_decl); if (id != TREE_OPERAND (t, 0)) { r = build_nt (LOOKUP_EXPR, id); LOOKUP_EXPR_GLOBAL (r) = LOOKUP_EXPR_GLOBAL (t); t = r; } return t; } case CAST_EXPR: case REINTERPRET_CAST_EXPR: case CONST_CAST_EXPR: case STATIC_CAST_EXPR: case DYNAMIC_CAST_EXPR: case NOP_EXPR: return build1 (code, tsubst (TREE_TYPE (t), args, in_decl), tsubst_copy (TREE_OPERAND (t, 0), args, in_decl)); case INDIRECT_REF: case PREDECREMENT_EXPR: case PREINCREMENT_EXPR: case POSTDECREMENT_EXPR: case POSTINCREMENT_EXPR: case NEGATE_EXPR: case TRUTH_NOT_EXPR: case BIT_NOT_EXPR: case ADDR_EXPR: case CONVERT_EXPR: /* Unary + */ case SIZEOF_EXPR: case ALIGNOF_EXPR: case ARROW_EXPR: case THROW_EXPR: case TYPEID_EXPR: return build1 (code, NULL_TREE, tsubst_copy (TREE_OPERAND (t, 0), args, in_decl)); case PLUS_EXPR: case MINUS_EXPR: case MULT_EXPR: case TRUNC_DIV_EXPR: case CEIL_DIV_EXPR: case FLOOR_DIV_EXPR: case ROUND_DIV_EXPR: case EXACT_DIV_EXPR: case BIT_AND_EXPR: case BIT_ANDTC_EXPR: case BIT_IOR_EXPR: case BIT_XOR_EXPR: case TRUNC_MOD_EXPR: case FLOOR_MOD_EXPR: case TRUTH_ANDIF_EXPR: case TRUTH_ORIF_EXPR: case TRUTH_AND_EXPR: case TRUTH_OR_EXPR: case RSHIFT_EXPR: case LSHIFT_EXPR: case RROTATE_EXPR: case LROTATE_EXPR: case EQ_EXPR: case NE_EXPR: case MAX_EXPR: case MIN_EXPR: case LE_EXPR: case GE_EXPR: case LT_EXPR: case GT_EXPR: case COMPONENT_REF: case ARRAY_REF: case COMPOUND_EXPR: case SCOPE_REF: case DOTSTAR_EXPR: case MEMBER_REF: return build_nt (code, tsubst_copy (TREE_OPERAND (t, 0), args, in_decl), tsubst_copy (TREE_OPERAND (t, 1), args, in_decl)); case CALL_EXPR: { tree fn = TREE_OPERAND (t, 0); if (is_overloaded_fn (fn)) fn = tsubst_copy (get_first_fn (fn), args, in_decl); else /* Sometimes FN is a LOOKUP_EXPR. */ fn = tsubst_copy (fn, args, in_decl); return build_nt (code, fn, tsubst_copy (TREE_OPERAND (t, 1), args, in_decl), NULL_TREE); } case METHOD_CALL_EXPR: { tree name = TREE_OPERAND (t, 0); if (TREE_CODE (name) == BIT_NOT_EXPR) { name = tsubst_copy (TREE_OPERAND (name, 0), args, in_decl); name = build1 (BIT_NOT_EXPR, NULL_TREE, name); } else if (TREE_CODE (name) == SCOPE_REF && TREE_CODE (TREE_OPERAND (name, 1)) == BIT_NOT_EXPR) { tree base = tsubst_copy (TREE_OPERAND (name, 0), args, in_decl); name = TREE_OPERAND (name, 1); name = tsubst_copy (TREE_OPERAND (name, 0), args, in_decl); name = build1 (BIT_NOT_EXPR, NULL_TREE, name); name = build_nt (SCOPE_REF, base, name); } else name = tsubst_copy (TREE_OPERAND (t, 0), args, in_decl); return build_nt (code, name, tsubst_copy (TREE_OPERAND (t, 1), args, in_decl), tsubst_copy (TREE_OPERAND (t, 2), args, in_decl), NULL_TREE); } case BIND_EXPR: case COND_EXPR: case MODOP_EXPR: { r = build_nt (code, tsubst_copy (TREE_OPERAND (t, 0), args, in_decl), tsubst_copy (TREE_OPERAND (t, 1), args, in_decl), tsubst_copy (TREE_OPERAND (t, 2), args, in_decl)); if (code == BIND_EXPR && !processing_template_decl) { /* This processing should really occur in tsubst_expr, However, tsubst_expr does not recurse into expressions, since it assumes that there aren't any statements inside them. Instead, it simply calls build_expr_from_tree. So, we need to expand the BIND_EXPR here. */ tree rtl_expr = begin_stmt_expr (); tree block = tsubst_expr (TREE_OPERAND (r, 1), args, in_decl); r = finish_stmt_expr (rtl_expr, block); } return r; } case NEW_EXPR: { r = build_nt (code, tsubst_copy (TREE_OPERAND (t, 0), args, in_decl), tsubst_copy (TREE_OPERAND (t, 1), args, in_decl), tsubst_copy (TREE_OPERAND (t, 2), args, in_decl)); NEW_EXPR_USE_GLOBAL (r) = NEW_EXPR_USE_GLOBAL (t); return r; } case DELETE_EXPR: { r = build_nt (code, tsubst_copy (TREE_OPERAND (t, 0), args, in_decl), tsubst_copy (TREE_OPERAND (t, 1), args, in_decl)); DELETE_EXPR_USE_GLOBAL (r) = DELETE_EXPR_USE_GLOBAL (t); DELETE_EXPR_USE_VEC (r) = DELETE_EXPR_USE_VEC (t); return r; } case TEMPLATE_ID_EXPR: { /* Substituted template arguments */ tree targs = tsubst_copy (TREE_OPERAND (t, 1), args, in_decl); tree chain; for (chain = targs; chain; chain = TREE_CHAIN (chain)) TREE_VALUE (chain) = maybe_fold_nontype_arg (TREE_VALUE (chain)); return lookup_template_function (tsubst_copy (TREE_OPERAND (t, 0), args, in_decl), targs); } case TREE_LIST: { tree purpose, value, chain; if (t == void_list_node) return t; purpose = TREE_PURPOSE (t); if (purpose) purpose = tsubst_copy (purpose, args, in_decl); value = TREE_VALUE (t); if (value) value = tsubst_copy (value, args, in_decl); chain = TREE_CHAIN (t); if (chain && chain != void_type_node) chain = tsubst_copy (chain, args, in_decl); if (purpose == TREE_PURPOSE (t) && value == TREE_VALUE (t) && chain == TREE_CHAIN (t)) return t; return tree_cons (purpose, value, chain); } case RECORD_TYPE: case UNION_TYPE: case ENUMERAL_TYPE: case INTEGER_TYPE: case TEMPLATE_TYPE_PARM: case TEMPLATE_TEMPLATE_PARM: case TEMPLATE_PARM_INDEX: case POINTER_TYPE: case REFERENCE_TYPE: case OFFSET_TYPE: case FUNCTION_TYPE: case METHOD_TYPE: case ARRAY_TYPE: case TYPENAME_TYPE: case TYPE_DECL: return tsubst (t, args, in_decl); case IDENTIFIER_NODE: if (IDENTIFIER_TYPENAME_P (t) /* Make sure it's not just a variable named `__opr', for instance, which can occur in some existing code. */ && TREE_TYPE (t)) return build_typename_overload (tsubst (TREE_TYPE (t), args, in_decl)); else return t; case CONSTRUCTOR: { r = build (CONSTRUCTOR, tsubst (TREE_TYPE (t), args, in_decl), NULL_TREE, tsubst_copy (CONSTRUCTOR_ELTS (t), args, in_decl)); TREE_HAS_CONSTRUCTOR (r) = TREE_HAS_CONSTRUCTOR (t); return r; } default: return t; } } /* Like tsubst_copy, but also does semantic processing and RTL expansion. */ tree tsubst_expr (t, args, in_decl) tree t, args; tree in_decl; { if (t == NULL_TREE || t == error_mark_node) return t; if (processing_template_decl) return tsubst_copy (t, args, in_decl); switch (TREE_CODE (t)) { case RETURN_STMT: lineno = TREE_COMPLEXITY (t); finish_return_stmt (tsubst_expr (RETURN_EXPR (t), args, in_decl)); break; case EXPR_STMT: lineno = TREE_COMPLEXITY (t); finish_expr_stmt (tsubst_expr (EXPR_STMT_EXPR (t), args, in_decl)); break; case DECL_STMT: { int i = suspend_momentary (); tree dcl, init; lineno = TREE_COMPLEXITY (t); emit_line_note (input_filename, lineno); dcl = start_decl (tsubst (TREE_OPERAND (t, 0), args, in_decl), tsubst (TREE_OPERAND (t, 1), args, in_decl), TREE_OPERAND (t, 2) != 0, NULL_TREE, NULL_TREE); init = tsubst_expr (TREE_OPERAND (t, 2), args, in_decl); cp_finish_decl (dcl, init, NULL_TREE, 1, /*init ? LOOKUP_ONLYCONVERTING :*/ 0); resume_momentary (i); return dcl; } case FOR_STMT: { tree tmp; lineno = TREE_COMPLEXITY (t); begin_for_stmt (); for (tmp = FOR_INIT_STMT (t); tmp; tmp = TREE_CHAIN (tmp)) tsubst_expr (tmp, args, in_decl); finish_for_init_stmt (NULL_TREE); finish_for_cond (tsubst_expr (FOR_COND (t), args, in_decl), NULL_TREE); tmp = tsubst_expr (FOR_EXPR (t), args, in_decl); finish_for_expr (tmp, NULL_TREE); tsubst_expr (FOR_BODY (t), args, in_decl); finish_for_stmt (tmp, NULL_TREE); } break; case WHILE_STMT: { lineno = TREE_COMPLEXITY (t); begin_while_stmt (); finish_while_stmt_cond (tsubst_expr (WHILE_COND (t), args, in_decl), NULL_TREE); tsubst_expr (WHILE_BODY (t), args, in_decl); finish_while_stmt (NULL_TREE); } break; case DO_STMT: { lineno = TREE_COMPLEXITY (t); begin_do_stmt (); tsubst_expr (DO_BODY (t), args, in_decl); finish_do_body (NULL_TREE); finish_do_stmt (tsubst_expr (DO_COND (t), args, in_decl), NULL_TREE); } break; case IF_STMT: { tree tmp; lineno = TREE_COMPLEXITY (t); begin_if_stmt (); finish_if_stmt_cond (tsubst_expr (IF_COND (t), args, in_decl), NULL_TREE); if (tmp = THEN_CLAUSE (t), tmp) { tsubst_expr (tmp, args, in_decl); finish_then_clause (NULL_TREE); } if (tmp = ELSE_CLAUSE (t), tmp) { begin_else_clause (); tsubst_expr (tmp, args, in_decl); finish_else_clause (NULL_TREE); } finish_if_stmt (); } break; case COMPOUND_STMT: { tree substmt; lineno = TREE_COMPLEXITY (t); begin_compound_stmt (COMPOUND_STMT_NO_SCOPE (t)); for (substmt = COMPOUND_BODY (t); substmt != NULL_TREE; substmt = TREE_CHAIN (substmt)) tsubst_expr (substmt, args, in_decl); return finish_compound_stmt (COMPOUND_STMT_NO_SCOPE (t), NULL_TREE); } break; case BREAK_STMT: lineno = TREE_COMPLEXITY (t); finish_break_stmt (); break; case CONTINUE_STMT: lineno = TREE_COMPLEXITY (t); finish_continue_stmt (); break; case SWITCH_STMT: { tree val, tmp; lineno = TREE_COMPLEXITY (t); begin_switch_stmt (); val = tsubst_expr (SWITCH_COND (t), args, in_decl); finish_switch_cond (val); if (tmp = TREE_OPERAND (t, 1), tmp) tsubst_expr (tmp, args, in_decl); finish_switch_stmt (val, NULL_TREE); } break; case CASE_LABEL: finish_case_label (tsubst_expr (CASE_LOW (t), args, in_decl), tsubst_expr (CASE_HIGH (t), args, in_decl)); break; case LABEL_DECL: t = define_label (DECL_SOURCE_FILE (t), DECL_SOURCE_LINE (t), DECL_NAME (t)); if (t) expand_label (t); break; case GOTO_STMT: lineno = TREE_COMPLEXITY (t); t = GOTO_DESTINATION (t); if (TREE_CODE (t) != IDENTIFIER_NODE) /* Computed goto's must be tsubst'd into. On the other hand, non-computed gotos must not be; the identifier in question will have no binding. */ t = tsubst_expr (t, args, in_decl); finish_goto_stmt (t); break; case ASM_STMT: lineno = TREE_COMPLEXITY (t); finish_asm_stmt (tsubst_expr (ASM_CV_QUAL (t), args, in_decl), tsubst_expr (ASM_STRING (t), args, in_decl), tsubst_expr (ASM_OUTPUTS (t), args, in_decl), tsubst_expr (ASM_INPUTS (t), args, in_decl), tsubst_expr (ASM_CLOBBERS (t), args, in_decl)); break; case TRY_BLOCK: lineno = TREE_COMPLEXITY (t); begin_try_block (); tsubst_expr (TRY_STMTS (t), args, in_decl); finish_try_block (NULL_TREE); { tree handler = TRY_HANDLERS (t); for (; handler; handler = TREE_CHAIN (handler)) tsubst_expr (handler, args, in_decl); } finish_handler_sequence (NULL_TREE); break; case HANDLER: lineno = TREE_COMPLEXITY (t); begin_handler (); if (HANDLER_PARMS (t)) { tree d = HANDLER_PARMS (t); expand_start_catch_block (tsubst (TREE_OPERAND (d, 1), args, in_decl), tsubst (TREE_OPERAND (d, 0), args, in_decl)); } else expand_start_catch_block (NULL_TREE, NULL_TREE); finish_handler_parms (NULL_TREE); tsubst_expr (HANDLER_BODY (t), args, in_decl); finish_handler (NULL_TREE); break; case TAG_DEFN: lineno = TREE_COMPLEXITY (t); t = TREE_TYPE (t); if (TREE_CODE (t) == ENUMERAL_TYPE) tsubst (t, args, NULL_TREE); break; default: return build_expr_from_tree (tsubst_copy (t, args, in_decl)); } return NULL_TREE; } /* Instantiate the indicated variable or function template TMPL with the template arguments in TARG_PTR. */ tree instantiate_template (tmpl, targ_ptr) tree tmpl, targ_ptr; { tree fndecl; tree gen_tmpl; tree spec; int i, len; struct obstack *old_fmp_obstack; extern struct obstack *function_maybepermanent_obstack; tree inner_args; if (tmpl == error_mark_node) return error_mark_node; my_friendly_assert (TREE_CODE (tmpl) == TEMPLATE_DECL, 283); /* Check to see if we already have this specialization. */ spec = retrieve_specialization (tmpl, targ_ptr); if (spec != NULL_TREE) return spec; if (DECL_TEMPLATE_INFO (tmpl)) { /* The TMPL is a partial instantiation. To get a full set of arguments we must add the arguments used to perform the partial instantiation. */ targ_ptr = add_outermost_template_args (DECL_TI_ARGS (tmpl), targ_ptr); gen_tmpl = most_general_template (tmpl); /* Check to see if we already have this specialization. */ spec = retrieve_specialization (gen_tmpl, targ_ptr); if (spec != NULL_TREE) return spec; } else gen_tmpl = tmpl; push_obstacks (&permanent_obstack, &permanent_obstack); old_fmp_obstack = function_maybepermanent_obstack; function_maybepermanent_obstack = &permanent_obstack; len = DECL_NTPARMS (gen_tmpl); inner_args = innermost_args (targ_ptr); i = len; while (i--) { tree t = TREE_VEC_ELT (inner_args, i); if (TREE_CODE_CLASS (TREE_CODE (t)) == 't') { tree nt = target_type (t); if (IS_AGGR_TYPE (nt) && decl_function_context (TYPE_MAIN_DECL (nt))) { cp_error ("type `%T' composed from a local class is not a valid template-argument", t); cp_error (" trying to instantiate `%D'", gen_tmpl); fndecl = error_mark_node; goto out; } } } targ_ptr = copy_to_permanent (targ_ptr); /* substitute template parameters */ fndecl = tsubst (DECL_RESULT (gen_tmpl), targ_ptr, gen_tmpl); /* The DECL_TI_TEMPLATE should always be the immediate parent template, not the most general template. */ DECL_TI_TEMPLATE (fndecl) = tmpl; if (flag_external_templates) add_pending_template (fndecl); out: function_maybepermanent_obstack = old_fmp_obstack; pop_obstacks (); return fndecl; } /* Push the name of the class template into the scope of the instantiation. */ void overload_template_name (type) tree type; { tree id = DECL_NAME (CLASSTYPE_TI_TEMPLATE (type)); tree decl; if (IDENTIFIER_CLASS_VALUE (id) && TREE_TYPE (IDENTIFIER_CLASS_VALUE (id)) == type) return; decl = build_decl (TYPE_DECL, id, type); SET_DECL_ARTIFICIAL (decl); pushdecl_class_level (decl); } /* Like type_unification but designed specially to handle conversion operators. The FN is a TEMPLATE_DECL for a function. The ARGS are the arguments that are being used when calling it. If FN is a conversion operator, RETURN_TYPE is the type desired as the result of the conversion operator. The EXTRA_FN_ARG, if any, is the type of an additional parameter to be added to the beginning of FN's parameter list. The other arguments are as for type_unification. */ int fn_type_unification (fn, explicit_targs, targs, args, return_type, strict, extra_fn_arg) tree fn, explicit_targs, targs, args, return_type; unification_kind_t strict; tree extra_fn_arg; { tree parms; my_friendly_assert (TREE_CODE (fn) == TEMPLATE_DECL, 0); parms = TYPE_ARG_TYPES (TREE_TYPE (fn)); if (DECL_CONV_FN_P (fn)) { /* This is a template conversion operator. Use the return types as well as the argument types. */ parms = scratch_tree_cons (NULL_TREE, TREE_TYPE (TREE_TYPE (fn)), parms); args = scratch_tree_cons (NULL_TREE, return_type, args); } if (extra_fn_arg != NULL_TREE) parms = scratch_tree_cons (NULL_TREE, extra_fn_arg, parms); /* We allow incomplete unification without an error message here because the standard doesn't seem to explicitly prohibit it. Our callers must be ready to deal with unification failures in any event. */ return type_unification (DECL_INNERMOST_TEMPLATE_PARMS (fn), targs, parms, args, explicit_targs, strict, 1); } /* Type unification. We have a function template signature with one or more references to template parameters, and a parameter list we wish to fit to this template. If possible, produce a list of parameters for the template which will cause it to fit the supplied parameter list. Return zero for success, 2 for an incomplete match that doesn't resolve all the types, and 1 for complete failure. An error message will be printed only for an incomplete match. TPARMS[NTPARMS] is an array of template parameter types. TARGS[NTPARMS] is the array into which the deduced template parameter values are placed. PARMS is the function template's signature (using TEMPLATE_PARM_IDX nodes), and ARGS is the argument list we're trying to match against it. The EXPLICIT_TARGS are explicit template arguments provided via a template-id. The parameter STRICT is one of: DEDUCE_CALL: We are deducing arguments for a function call, as in [temp.deduct.call]. DEDUCE_CONV: We are deducing arguments for a conversion function, as in [temp.deduct.conv]. DEDUCE_EXACT: We are deducing arguments when calculating the partial ordering between specializations of function or class templates, as in [temp.func.order] and [temp.class.order], when doing an explicit instantiation as in [temp.explicit], when determining an explicit specialization as in [temp.expl.spec], or when taking the address of a function template, as in [temp.deduct.funcaddr]. */ int type_unification (tparms, targs, parms, args, explicit_targs, strict, allow_incomplete) tree tparms, targs, parms, args, explicit_targs; unification_kind_t strict; int allow_incomplete; { int* explicit_mask; int i; for (i = 0; i < TREE_VEC_LENGTH (tparms); i++) TREE_VEC_ELT (targs, i) = NULL_TREE; if (explicit_targs != NULL_TREE) { tree arg_vec; arg_vec = coerce_template_parms (tparms, explicit_targs, NULL_TREE, 0, 0); if (arg_vec == error_mark_node) return 1; explicit_mask = alloca (sizeof (int) * TREE_VEC_LENGTH (targs)); bzero ((char *) explicit_mask, sizeof(int) * TREE_VEC_LENGTH (targs)); for (i = 0; i < TREE_VEC_LENGTH (arg_vec) && TREE_VEC_ELT (arg_vec, i) != NULL_TREE; ++i) { TREE_VEC_ELT (targs, i) = TREE_VEC_ELT (arg_vec, i); /* Let unify know that this argument was explicit. */ explicit_mask [i] = 1; } } else explicit_mask = 0; return type_unification_real (tparms, targs, parms, args, 0, strict, allow_incomplete, explicit_mask); } /* Adjust types before performing type deduction, as described in [temp.deduct.call] and [temp.deduct.conv]. The rules in these two sections are symmetric. PARM is the type of a function parameter or the return type of the conversion function. ARG is the type of the argument passed to the call, or the type of the value intialized with the result of the conversion function. */ void maybe_adjust_types_for_deduction (strict, parm, arg) unification_kind_t strict; tree* parm; tree* arg; { switch (strict) { case DEDUCE_CALL: break; case DEDUCE_CONV: { /* Swap PARM and ARG throughout the remainder of this function; the handling is precisely symmetric since PARM will initialize ARG rather than vice versa. */ tree* temp = parm; parm = arg; arg = temp; break; } case DEDUCE_EXACT: /* There is nothing to do in this case. */ return; default: my_friendly_abort (0); } if (TREE_CODE (*parm) != REFERENCE_TYPE) { /* [temp.deduct.call] If P is not a reference type: --If A is an array type, the pointer type produced by the array-to-pointer standard conversion (_conv.array_) is used in place of A for type deduction; otherwise, --If A is a function type, the pointer type produced by the function-to-pointer standard conversion (_conv.func_) is used in place of A for type deduction; otherwise, --If A is a cv-qualified type, the top level cv-qualifiers of A's type are ignored for type deduction. */ if (TREE_CODE (*arg) == ARRAY_TYPE) *arg = build_pointer_type (TREE_TYPE (*arg)); else if (TREE_CODE (*arg) == FUNCTION_TYPE || TREE_CODE (*arg) == METHOD_TYPE) *arg = build_pointer_type (*arg); else *arg = TYPE_MAIN_VARIANT (*arg); } /* [temp.deduct.call] If P is a cv-qualified type, the top level cv-qualifiers of P's type are ignored for type deduction. If P is a reference type, the type referred to by P is used for type deduction. */ *parm = TYPE_MAIN_VARIANT (*parm); if (TREE_CODE (*parm) == REFERENCE_TYPE) *parm = TREE_TYPE (*parm); } /* Like type_unfication. EXPLICIT_MASK, if non-NULL, is an array of integers, with ones in positions corresponding to arguments in targs that were provided explicitly, and zeros elsewhere. If SUBR is 1, we're being called recursively (to unify the arguments of a function or method parameter of a function template). */ static int type_unification_real (tparms, targs, parms, args, subr, strict, allow_incomplete, explicit_mask) tree tparms, targs, parms, args; int subr; unification_kind_t strict; int allow_incomplete; int* explicit_mask; { tree parm, arg; int i; int ntparms = TREE_VEC_LENGTH (tparms); int sub_strict; my_friendly_assert (TREE_CODE (tparms) == TREE_VEC, 289); my_friendly_assert (parms == NULL_TREE || TREE_CODE (parms) == TREE_LIST, 290); /* ARGS could be NULL (via a call from parse.y to build_x_function_call). */ if (args) my_friendly_assert (TREE_CODE (args) == TREE_LIST, 291); my_friendly_assert (ntparms > 0, 292); switch (strict) { case DEDUCE_CALL: sub_strict = UNIFY_ALLOW_MORE_CV_QUAL | UNIFY_ALLOW_DERIVED; break; case DEDUCE_CONV: sub_strict = UNIFY_ALLOW_LESS_CV_QUAL; break; case DEDUCE_EXACT: sub_strict = UNIFY_ALLOW_NONE; break; default: my_friendly_abort (0); } while (parms && parms != void_list_node && args && args != void_list_node) { parm = TREE_VALUE (parms); parms = TREE_CHAIN (parms); arg = TREE_VALUE (args); args = TREE_CHAIN (args); if (arg == error_mark_node) return 1; if (arg == unknown_type_node) /* We can't deduce anything from this, but we might get all the template args from other function args. */ continue; /* Conversions will be performed on a function argument that corresponds with a function parameter that contains only non-deducible template parameters and explicitly specified template parameters. */ if (! uses_template_parms (parm)) { tree type; if (TREE_CODE_CLASS (TREE_CODE (arg)) != 't') type = TREE_TYPE (arg); else { type = arg; arg = NULL_TREE; } if (strict == DEDUCE_EXACT) { if (same_type_p (parm, type)) continue; } else /* It might work; we shouldn't check now, because we might get into infinite recursion. Overload resolution will handle it. */ continue; return 1; } #if 0 if (TREE_CODE (arg) == VAR_DECL) arg = TREE_TYPE (arg); else if (TREE_CODE_CLASS (TREE_CODE (arg)) == 'e') arg = TREE_TYPE (arg); #else if (TREE_CODE_CLASS (TREE_CODE (arg)) != 't') { my_friendly_assert (TREE_TYPE (arg) != NULL_TREE, 293); if (type_unknown_p (arg)) { /* [temp.deduct.type] A template-argument can be deduced from a pointer to function or pointer to member function argument if the set of overloaded functions does not contain function templates and at most one of a set of overloaded functions provides a unique match. */ if (resolve_overloaded_unification (tparms, targs, parm, arg, strict, sub_strict, explicit_mask) != 0) return 1; continue; } arg = TREE_TYPE (arg); } #endif if (!subr) maybe_adjust_types_for_deduction (strict, &parm, &arg); switch (unify (tparms, targs, parm, arg, sub_strict, explicit_mask)) { case 0: break; case 1: return 1; } } /* Fail if we've reached the end of the parm list, and more args are present, and the parm list isn't variadic. */ if (args && args != void_list_node && parms == void_list_node) return 1; /* Fail if parms are left and they don't have default values. */ if (parms && parms != void_list_node && TREE_PURPOSE (parms) == NULL_TREE) return 1; if (!subr) for (i = 0; i < ntparms; i++) if (TREE_VEC_ELT (targs, i) == NULL_TREE) { if (!allow_incomplete) error ("incomplete type unification"); return 2; } return 0; } /* Subroutine of type_unification_real. Args are like the variables at the call site. ARG is an overloaded function (or template-id); we try deducing template args from each of the overloads, and if only one succeeds, we go with that. Modifies TARGS and returns 0 on success. */ static int resolve_overloaded_unification (tparms, targs, parm, arg, strict, sub_strict, explicit_mask) tree tparms, targs, parm, arg; unification_kind_t strict; int sub_strict; int* explicit_mask; { tree tempargs = copy_node (targs); int good = 0; if (TREE_CODE (arg) == ADDR_EXPR) arg = TREE_OPERAND (arg, 0); if (TREE_CODE (arg) == TEMPLATE_ID_EXPR) { /* If we got some explicit template args, we need to plug them into the affected templates before we try to unify, in case the explicit args will completely resolve the templates in question. */ tree expl_subargs = TREE_OPERAND (arg, 1); arg = TREE_OPERAND (arg, 0); for (; arg; arg = OVL_NEXT (arg)) { tree fn = OVL_CURRENT (arg); tree subargs, elem; if (TREE_CODE (fn) != TEMPLATE_DECL) continue; subargs = get_bindings_overload (fn, DECL_RESULT (fn), expl_subargs); if (subargs) { elem = tsubst (TREE_TYPE (fn), subargs, NULL_TREE); good += try_one_overload (tparms, targs, tempargs, parm, elem, strict, sub_strict, explicit_mask); } } } else if (TREE_CODE (arg) == OVERLOAD) { for (; arg; arg = OVL_NEXT (arg)) good += try_one_overload (tparms, targs, tempargs, parm, TREE_TYPE (OVL_CURRENT (arg)), strict, sub_strict, explicit_mask); } else my_friendly_abort (981006); /* [temp.deduct.type] A template-argument can be deduced from a pointer to function or pointer to member function argument if the set of overloaded functions does not contain function templates and at most one of a set of overloaded functions provides a unique match. So if we found multiple possibilities, we return success but don't deduce anything. */ if (good == 1) { int i = TREE_VEC_LENGTH (targs); for (; i--; ) if (TREE_VEC_ELT (tempargs, i)) TREE_VEC_ELT (targs, i) = TREE_VEC_ELT (tempargs, i); } if (good) return 0; return 1; } /* Subroutine of resolve_overloaded_unification; does deduction for a single overload. Fills TARGS with any deduced arguments, or error_mark_node if different overloads deduce different arguments for a given parm. Returns 1 on success. */ static int try_one_overload (tparms, orig_targs, targs, parm, arg, strict, sub_strict, explicit_mask) tree tparms, orig_targs, targs, parm, arg; unification_kind_t strict; int sub_strict; int* explicit_mask; { int nargs; tree tempargs; int i; /* [temp.deduct.type] A template-argument can be deduced from a pointer to function or pointer to member function argument if the set of overloaded functions does not contain function templates and at most one of a set of overloaded functions provides a unique match. So if this is a template, just return success. */ if (uses_template_parms (arg)) return 1; maybe_adjust_types_for_deduction (strict, &parm, &arg); /* We don't copy orig_targs for this because if we have already deduced some template args from previous args, unify would complain when we try to deduce a template parameter for the same argument, even though there isn't really a conflict. */ nargs = TREE_VEC_LENGTH (targs); tempargs = make_scratch_vec (nargs); if (unify (tparms, tempargs, parm, arg, sub_strict, explicit_mask) != 0) return 0; /* First make sure we didn't deduce anything that conflicts with explicitly specified args. */ for (i = nargs; i--; ) { tree elt = TREE_VEC_ELT (tempargs, i); tree oldelt = TREE_VEC_ELT (orig_targs, i); if (elt == NULL_TREE) continue; else if (uses_template_parms (elt)) { /* Since we're unifying against ourselves, we will fill in template args used in the function parm list with our own template parms. Discard them. */ TREE_VEC_ELT (tempargs, i) = NULL_TREE; continue; } else if (oldelt && ! template_args_equal (oldelt, elt)) return 0; } for (i = nargs; i--; ) { tree elt = TREE_VEC_ELT (tempargs, i); if (elt) TREE_VEC_ELT (targs, i) = elt; } return 1; } /* Returns the level of DECL, which declares a template parameter. */ int template_decl_level (decl) tree decl; { switch (TREE_CODE (decl)) { case TYPE_DECL: case TEMPLATE_DECL: return TEMPLATE_TYPE_LEVEL (TREE_TYPE (decl)); case PARM_DECL: return TEMPLATE_PARM_LEVEL (DECL_INITIAL (decl)); default: my_friendly_abort (0); return 0; } } /* Decide whether ARG can be unified with PARM, considering only the cv-qualifiers of each type, given STRICT as documented for unify. Returns non-zero iff the unification is OK on that basis.*/ int check_cv_quals_for_unify (strict, arg, parm) int strict; tree arg; tree parm; { return !((!(strict & UNIFY_ALLOW_MORE_CV_QUAL) && !at_least_as_qualified_p (arg, parm)) || (!(strict & UNIFY_ALLOW_LESS_CV_QUAL) && (!at_least_as_qualified_p (parm, arg)))); } /* Takes parameters as for type_unification. Returns 0 if the type deduction suceeds, 1 otherwise. The parameter STRICT is a bitwise or of the following flags: UNIFY_ALLOW_NONE: Require an exact match between PARM and ARG. UNIFY_ALLOW_MORE_CV_QUAL: Allow the deduced ARG to be more cv-qualified than ARG. UNIFY_ALLOW_LESS_CV_QUAL: Allow the deduced ARG to be less cv-qualified than ARG. UNIFY_ALLOW_DERIVED: Allow the deduced ARG to be a template base class of ARG, or a pointer to a template base class of the type pointed to by ARG. UNIFY_ALLOW_INTEGER: Allow any integral type to be deduced. See the TEMPLATE_PARM_INDEX case for more information. */ int unify (tparms, targs, parm, arg, strict, explicit_mask) tree tparms, targs, parm, arg; int strict; int* explicit_mask; { int idx; tree targ; tree tparm; /* I don't think this will do the right thing with respect to types. But the only case I've seen it in so far has been array bounds, where signedness is the only information lost, and I think that will be okay. */ while (TREE_CODE (parm) == NOP_EXPR) parm = TREE_OPERAND (parm, 0); if (arg == error_mark_node) return 1; if (arg == unknown_type_node) /* We can't deduce anything from this, but we might get all the template args from other function args. */ return 0; /* If PARM uses template parameters, then we can't bail out here, even in ARG == PARM, since we won't record unifications for the template parameters. We might need them if we're trying to figure out which of two things is more specialized. */ if (arg == parm && !uses_template_parms (parm)) return 0; /* Immediately reject some pairs that won't unify because of cv-qualification mismatches. */ if (TREE_CODE (arg) == TREE_CODE (parm) && TREE_CODE_CLASS (TREE_CODE (arg)) == 't' /* We check the cv-qualifiers when unifying with template type parameters below. We want to allow ARG `const T' to unify with PARM `T' for example, when computing which of two templates is more specialized, for example. */ && TREE_CODE (arg) != TEMPLATE_TYPE_PARM && !check_cv_quals_for_unify (strict, arg, parm)) return 1; switch (TREE_CODE (parm)) { case TYPENAME_TYPE: /* In a type which contains a nested-name-specifier, template argument values cannot be deduced for template parameters used within the nested-name-specifier. */ return 0; case TEMPLATE_TYPE_PARM: case TEMPLATE_TEMPLATE_PARM: tparm = TREE_VALUE (TREE_VEC_ELT (tparms, 0)); if (TEMPLATE_TYPE_LEVEL (parm) != template_decl_level (tparm)) /* The PARM is not one we're trying to unify. Just check to see if it matches ARG. */ return (TREE_CODE (arg) == TREE_CODE (parm) && same_type_p (parm, arg)) ? 0 : 1; idx = TEMPLATE_TYPE_IDX (parm); targ = TREE_VEC_ELT (targs, idx); tparm = TREE_VALUE (TREE_VEC_ELT (tparms, idx)); /* Check for mixed types and values. */ if ((TREE_CODE (parm) == TEMPLATE_TYPE_PARM && TREE_CODE (tparm) != TYPE_DECL) || (TREE_CODE (parm) == TEMPLATE_TEMPLATE_PARM && TREE_CODE (tparm) != TEMPLATE_DECL)) return 1; if (!strict && targ != NULL_TREE && explicit_mask && explicit_mask[idx]) /* An explicit template argument. Don't even try to match here; the overload resolution code will manage check to see whether the call is legal. */ return 0; if (TREE_CODE (parm) == TEMPLATE_TEMPLATE_PARM) { if (TEMPLATE_TEMPLATE_PARM_TEMPLATE_INFO (parm)) { /* We arrive here when PARM does not involve template specialization. */ /* ARG must be constructed from a template class. */ if (TREE_CODE (arg) != RECORD_TYPE || !CLASSTYPE_TEMPLATE_INFO (arg)) return 1; { tree parmtmpl = TYPE_TI_TEMPLATE (parm); tree parmvec = TYPE_TI_ARGS (parm); tree argvec = CLASSTYPE_TI_ARGS (arg); tree argtmplvec = DECL_INNERMOST_TEMPLATE_PARMS (CLASSTYPE_TI_TEMPLATE (arg)); int i; /* The parameter and argument roles have to be switched here in order to handle default arguments properly. For example, template<template <class> class TT> void f(TT<int>) should be able to accept vector<int> which comes from template <class T, class Allocator = allocator> class vector. */ if (coerce_template_parms (argtmplvec, parmvec, parmtmpl, 1, 1) == error_mark_node) return 1; /* Deduce arguments T, i from TT<T> or TT<i>. */ for (i = 0; i < TREE_VEC_LENGTH (parmvec); ++i) { tree t = TREE_VEC_ELT (parmvec, i); if (TREE_CODE (t) != TEMPLATE_TYPE_PARM && TREE_CODE (t) != TEMPLATE_TEMPLATE_PARM && TREE_CODE (t) != TEMPLATE_PARM_INDEX) continue; /* This argument can be deduced. */ if (unify (tparms, targs, t, TREE_VEC_ELT (argvec, i), UNIFY_ALLOW_NONE, explicit_mask)) return 1; } } arg = CLASSTYPE_TI_TEMPLATE (arg); } } else { /* If PARM is `const T' and ARG is only `int', we don't have a match unless we are allowing additional qualification. If ARG is `const int' and PARM is just `T' that's OK; that binds `const int' to `T'. */ if (!check_cv_quals_for_unify (strict | UNIFY_ALLOW_LESS_CV_QUAL, arg, parm)) return 1; /* Consider the case where ARG is `const volatile int' and PARM is `const T'. Then, T should be `volatile int'. */ arg = cp_build_qualified_type (arg, CP_TYPE_QUALS (arg) & ~CP_TYPE_QUALS (parm)); } /* Simple cases: Value already set, does match or doesn't. */ if (targ != NULL_TREE && (same_type_p (targ, arg) || (explicit_mask && explicit_mask[idx]))) return 0; else if (targ) return 1; TREE_VEC_ELT (targs, idx) = arg; return 0; case TEMPLATE_PARM_INDEX: tparm = TREE_VALUE (TREE_VEC_ELT (tparms, 0)); if (TEMPLATE_PARM_LEVEL (parm) != template_decl_level (tparm)) /* The PARM is not one we're trying to unify. Just check to see if it matches ARG. */ return (TREE_CODE (arg) == TREE_CODE (parm) && cp_tree_equal (parm, arg) > 0) ? 0 : 1; idx = TEMPLATE_PARM_IDX (parm); targ = TREE_VEC_ELT (targs, idx); if (targ) { int i = (cp_tree_equal (targ, arg) > 0); if (i == 1) return 0; else if (i == 0) return 1; else my_friendly_abort (42); } /* [temp.deduct.type] If, in the declaration of a function template with a non-type template-parameter, the non-type template-parameter is used in an expression in the function parameter-list and, if the corresponding template-argument is deduced, the template-argument type shall match the type of the template-parameter exactly, except that a template-argument deduced from an array bound may be of any integral type. */ if (same_type_p (TREE_TYPE (arg), TREE_TYPE (parm))) /* OK */; else if ((strict & UNIFY_ALLOW_INTEGER) && (TREE_CODE (TREE_TYPE (parm)) == INTEGER_TYPE || TREE_CODE (TREE_TYPE (parm)) == BOOLEAN_TYPE)) /* OK */; else return 1; TREE_VEC_ELT (targs, idx) = copy_to_permanent (arg); return 0; case POINTER_TYPE: { int sub_strict; if (TREE_CODE (arg) == RECORD_TYPE && TYPE_PTRMEMFUNC_FLAG (arg)) return (unify (tparms, targs, parm, TYPE_PTRMEMFUNC_FN_TYPE (arg), strict, explicit_mask)); if (TREE_CODE (arg) != POINTER_TYPE) return 1; /* [temp.deduct.call] A can be another pointer or pointer to member type that can be converted to the deduced A via a qualification conversion (_conv.qual_). We pass down STRICT here rather than UNIFY_ALLOW_NONE. This will allow for additional cv-qualification of the pointed-to types if appropriate. In general, this is a bit too generous; we are only supposed to allow qualification conversions and this method will allow an ARG of char** and a deduced ARG of const char**. However, overload resolution will subsequently invalidate the candidate, so this is probably OK. */ sub_strict = strict; if (TREE_CODE (TREE_TYPE (arg)) != RECORD_TYPE || TYPE_PTRMEMFUNC_FLAG (TREE_TYPE (arg))) /* The derived-to-base conversion only persists through one level of pointers. */ sub_strict &= ~UNIFY_ALLOW_DERIVED; return unify (tparms, targs, TREE_TYPE (parm), TREE_TYPE (arg), sub_strict, explicit_mask); } case REFERENCE_TYPE: if (TREE_CODE (arg) != REFERENCE_TYPE) return 1; return unify (tparms, targs, TREE_TYPE (parm), TREE_TYPE (arg), UNIFY_ALLOW_NONE, explicit_mask); case ARRAY_TYPE: if (TREE_CODE (arg) != ARRAY_TYPE) return 1; if ((TYPE_DOMAIN (parm) == NULL_TREE) != (TYPE_DOMAIN (arg) == NULL_TREE)) return 1; if (TYPE_DOMAIN (parm) != NULL_TREE && unify (tparms, targs, TYPE_DOMAIN (parm), TYPE_DOMAIN (arg), UNIFY_ALLOW_NONE, explicit_mask) != 0) return 1; return unify (tparms, targs, TREE_TYPE (parm), TREE_TYPE (arg), UNIFY_ALLOW_NONE, explicit_mask); case REAL_TYPE: case COMPLEX_TYPE: case INTEGER_TYPE: case BOOLEAN_TYPE: case VOID_TYPE: if (TREE_CODE (arg) != TREE_CODE (parm)) return 1; if (TREE_CODE (parm) == INTEGER_TYPE && TREE_CODE (TYPE_MAX_VALUE (parm)) != INTEGER_CST) { if (TYPE_MIN_VALUE (parm) && TYPE_MIN_VALUE (arg) && unify (tparms, targs, TYPE_MIN_VALUE (parm), TYPE_MIN_VALUE (arg), UNIFY_ALLOW_INTEGER, explicit_mask)) return 1; if (TYPE_MAX_VALUE (parm) && TYPE_MAX_VALUE (arg) && unify (tparms, targs, TYPE_MAX_VALUE (parm), TYPE_MAX_VALUE (arg), UNIFY_ALLOW_INTEGER, explicit_mask)) return 1; } /* We use the TYPE_MAIN_VARIANT since we have already checked cv-qualification at the top of the function. */ else if (!same_type_p (TYPE_MAIN_VARIANT (arg), TYPE_MAIN_VARIANT (parm))) return 1; /* As far as unification is concerned, this wins. Later checks will invalidate it if necessary. */ return 0; /* Types INTEGER_CST and MINUS_EXPR can come from array bounds. */ /* Type INTEGER_CST can come from ordinary constant template args. */ case INTEGER_CST: while (TREE_CODE (arg) == NOP_EXPR) arg = TREE_OPERAND (arg, 0); if (TREE_CODE (arg) != INTEGER_CST) return 1; return !tree_int_cst_equal (parm, arg); case TREE_VEC: { int i; if (TREE_CODE (arg) != TREE_VEC) return 1; if (TREE_VEC_LENGTH (parm) != TREE_VEC_LENGTH (arg)) return 1; for (i = TREE_VEC_LENGTH (parm) - 1; i >= 0; i--) if (unify (tparms, targs, TREE_VEC_ELT (parm, i), TREE_VEC_ELT (arg, i), UNIFY_ALLOW_NONE, explicit_mask)) return 1; return 0; } case RECORD_TYPE: if (TYPE_PTRMEMFUNC_FLAG (parm)) return unify (tparms, targs, TYPE_PTRMEMFUNC_FN_TYPE (parm), arg, strict, explicit_mask); if (TREE_CODE (arg) != RECORD_TYPE) return 1; if (CLASSTYPE_TEMPLATE_INFO (parm) && uses_template_parms (parm)) { tree t = NULL_TREE; if (strict & UNIFY_ALLOW_DERIVED) /* [temp.deduct.call] If P is a class, and P has the form template-id, then A can be a derived class of the deduced A. Likewise, if P is a pointer to a class of the form template-id, A can be a pointer to a derived class pointed to by the deduced A. The call to get_template_base also handles the case where PARM and ARG are the same type, i.e., where no derivation is involved. */ t = get_template_base (CLASSTYPE_TI_TEMPLATE (parm), arg); else if (CLASSTYPE_TEMPLATE_INFO (arg) && (CLASSTYPE_TI_TEMPLATE (parm) == CLASSTYPE_TI_TEMPLATE (arg))) /* Perhaps PARM is something like S<U> and ARG is S<int>. Then, we should unify `int' and `U'. */ t = arg; if (! t || t == error_mark_node) return 1; return unify (tparms, targs, CLASSTYPE_TI_ARGS (parm), CLASSTYPE_TI_ARGS (t), UNIFY_ALLOW_NONE, explicit_mask); } else if (!same_type_p (TYPE_MAIN_VARIANT (parm), TYPE_MAIN_VARIANT (arg))) return 1; return 0; case METHOD_TYPE: case FUNCTION_TYPE: if (TREE_CODE (arg) != TREE_CODE (parm)) return 1; if (unify (tparms, targs, TREE_TYPE (parm), TREE_TYPE (arg), UNIFY_ALLOW_NONE, explicit_mask)) return 1; return type_unification_real (tparms, targs, TYPE_ARG_TYPES (parm), TYPE_ARG_TYPES (arg), 1, DEDUCE_EXACT, 0, explicit_mask); case OFFSET_TYPE: if (TREE_CODE (arg) != OFFSET_TYPE) return 1; if (unify (tparms, targs, TYPE_OFFSET_BASETYPE (parm), TYPE_OFFSET_BASETYPE (arg), UNIFY_ALLOW_NONE, explicit_mask)) return 1; return unify (tparms, targs, TREE_TYPE (parm), TREE_TYPE (arg), UNIFY_ALLOW_NONE, explicit_mask); case CONST_DECL: if (arg != decl_constant_value (parm)) return 1; return 0; case TEMPLATE_DECL: /* Matched cases are handled by the ARG == PARM test above. */ return 1; case MINUS_EXPR: if (TREE_CODE (TREE_OPERAND (parm, 1)) == INTEGER_CST) { /* We handle this case specially, since it comes up with arrays. In particular, something like: template <int N> void f(int (&x)[N]); Here, we are trying to unify the range type, which looks like [0 ... (N - 1)]. */ tree t, t1, t2; t1 = TREE_OPERAND (parm, 0); t2 = TREE_OPERAND (parm, 1); /* Should this be a regular fold? */ t = maybe_fold_nontype_arg (build (PLUS_EXPR, integer_type_node, arg, t2)); return unify (tparms, targs, t1, t, strict, explicit_mask); } /* else fall through */ default: if (IS_EXPR_CODE_CLASS (TREE_CODE_CLASS (TREE_CODE (parm)))) { /* We're looking at an expression. This can happen with something like: template <int I> void foo(S<I>, S<I + 2>); If the call looked like: foo(S<2>(), S<4>()); we would have already matched `I' with `2'. Now, we'd like to know if `4' matches `I + 2'. So, we substitute into that expression, and fold constants, in the hope of figuring it out. */ tree t = maybe_fold_nontype_arg (tsubst_expr (parm, targs, NULL_TREE)); tree a = maybe_fold_nontype_arg (arg); if (!IS_EXPR_CODE_CLASS (TREE_CODE_CLASS (TREE_CODE (t)))) /* Good, we mangaged to simplify the exression. */ return unify (tparms, targs, t, a, UNIFY_ALLOW_NONE, explicit_mask); else /* Bad, we couldn't simplify this. Assume it doesn't unify. */ return 1; } else sorry ("use of `%s' in template type unification", tree_code_name [(int) TREE_CODE (parm)]); return 1; } } /* Called if RESULT is explicitly instantiated, or is a member of an explicitly instantiated class, or if using -frepo and the instantiation of RESULT has been assigned to this file. */ void mark_decl_instantiated (result, extern_p) tree result; int extern_p; { if (TREE_CODE (result) != FUNCTION_DECL) /* The TREE_PUBLIC flag for function declarations will have been set correctly by tsubst. */ TREE_PUBLIC (result) = 1; if (! extern_p) { DECL_INTERFACE_KNOWN (result) = 1; DECL_NOT_REALLY_EXTERN (result) = 1; /* Always make artificials weak. */ if (DECL_ARTIFICIAL (result) && flag_weak) comdat_linkage (result); /* For WIN32 we also want to put explicit instantiations in linkonce sections. */ else if (TREE_PUBLIC (result)) maybe_make_one_only (result); } else if (TREE_CODE (result) == FUNCTION_DECL) mark_inline_for_output (result); } /* Given two function templates PAT1 and PAT2, and explicit template arguments EXPLICIT_ARGS return: 1 if PAT1 is more specialized than PAT2 as described in [temp.func.order]. -1 if PAT2 is more specialized than PAT1. 0 if neither is more specialized. */ int more_specialized (pat1, pat2, explicit_args) tree pat1, pat2, explicit_args; { tree targs; int winner = 0; targs = get_bindings_overload (pat1, pat2, explicit_args); if (targs) --winner; targs = get_bindings_overload (pat2, pat1, explicit_args); if (targs) ++winner; return winner; } /* Given two class template specialization list nodes PAT1 and PAT2, return: 1 if PAT1 is more specialized than PAT2 as described in [temp.class.order]. -1 if PAT2 is more specialized than PAT1. 0 if neither is more specialized. */ int more_specialized_class (pat1, pat2) tree pat1, pat2; { tree targs; int winner = 0; targs = get_class_bindings (TREE_VALUE (pat1), TREE_PURPOSE (pat1), TREE_PURPOSE (pat2)); if (targs) --winner; targs = get_class_bindings (TREE_VALUE (pat2), TREE_PURPOSE (pat2), TREE_PURPOSE (pat1)); if (targs) ++winner; return winner; } /* Return the template arguments that will produce the function signature DECL from the function template FN, with the explicit template arguments EXPLICIT_ARGS. If CHECK_RETTYPE is 1, the return type must also match. */ static tree get_bindings_real (fn, decl, explicit_args, check_rettype) tree fn, decl, explicit_args; int check_rettype; { int ntparms = DECL_NTPARMS (fn); tree targs = make_scratch_vec (ntparms); tree decl_arg_types = TYPE_ARG_TYPES (TREE_TYPE (decl)); tree extra_fn_arg = NULL_TREE; int i; if (DECL_STATIC_FUNCTION_P (fn) && DECL_NONSTATIC_MEMBER_FUNCTION_P (decl)) { /* Sometimes we are trying to figure out what's being specialized by a declaration that looks like a method, and it turns out to be a static member function. */ if (CLASSTYPE_TEMPLATE_INFO (DECL_REAL_CONTEXT (fn)) && !is_member_template (fn)) /* The natural thing to do here seems to be to remove the spurious `this' parameter from the DECL, but that prevents unification from making use of the class type. So, instead, we have fn_type_unification add to the parameters for FN. */ extra_fn_arg = build_pointer_type (DECL_REAL_CONTEXT (fn)); else /* In this case, though, adding the extra_fn_arg can confuse things, so we remove from decl_arg_types instead. */ decl_arg_types = TREE_CHAIN (decl_arg_types); } i = fn_type_unification (fn, explicit_args, targs, decl_arg_types, TREE_TYPE (TREE_TYPE (decl)), DEDUCE_EXACT, extra_fn_arg); if (i != 0) return NULL_TREE; if (check_rettype) { /* Check to see that the resulting return type is also OK. */ tree t = tsubst (TREE_TYPE (TREE_TYPE (fn)), targs, NULL_TREE); if (!same_type_p (t, TREE_TYPE (TREE_TYPE (decl)))) return NULL_TREE; } return targs; } /* For most uses, we want to check the return type. */ tree get_bindings (fn, decl, explicit_args) tree fn, decl, explicit_args; { return get_bindings_real (fn, decl, explicit_args, 1); } /* But for more_specialized, we only care about the parameter types. */ static tree get_bindings_overload (fn, decl, explicit_args) tree fn, decl, explicit_args; { return get_bindings_real (fn, decl, explicit_args, 0); } /* Return the innermost template arguments that, when applied to a template specialization whose innermost template parameters are TPARMS, and whose specialization arguments are ARGS, yield the ARGS. For example, suppose we have: template <class T, class U> struct S {}; template <class T> struct S<T*, int> {}; Then, suppose we want to get `S<double*, int>'. The TPARMS will be {T}, the PARMS will be {T*, int} and the ARGS will be {double*, int}. The resulting vector will be {double}, indicating that `T' is bound to `double'. */ static tree get_class_bindings (tparms, parms, args) tree tparms, parms, args; { int i, ntparms = TREE_VEC_LENGTH (tparms); tree vec = make_temp_vec (ntparms); args = innermost_args (args); for (i = 0; i < TREE_VEC_LENGTH (parms); ++i) { switch (unify (tparms, vec, TREE_VEC_ELT (parms, i), TREE_VEC_ELT (args, i), UNIFY_ALLOW_NONE, 0)) { case 0: break; case 1: return NULL_TREE; } } for (i = 0; i < ntparms; ++i) if (! TREE_VEC_ELT (vec, i)) return NULL_TREE; return vec; } /* Return the most specialized of the list of templates in FNS that can produce an instantiation matching DECL, given the explicit template arguments EXPLICIT_ARGS. */ tree most_specialized (fns, decl, explicit_args) tree fns, decl, explicit_args; { tree candidates = NULL_TREE; tree fn, champ, args; int fate; for (fn = fns; fn; fn = TREE_CHAIN (fn)) { tree candidate = TREE_VALUE (fn); args = get_bindings (candidate, decl, explicit_args); if (args) candidates = scratch_tree_cons (NULL_TREE, candidate, candidates); } if (!candidates) return NULL_TREE; champ = TREE_VALUE (candidates); for (fn = TREE_CHAIN (candidates); fn; fn = TREE_CHAIN (fn)) { fate = more_specialized (champ, TREE_VALUE (fn), explicit_args); if (fate == 1) ; else { if (fate == 0) { fn = TREE_CHAIN (fn); if (! fn) return error_mark_node; } champ = TREE_VALUE (fn); } } for (fn = candidates; fn && TREE_VALUE (fn) != champ; fn = TREE_CHAIN (fn)) { fate = more_specialized (champ, TREE_VALUE (fn), explicit_args); if (fate != 1) return error_mark_node; } return champ; } /* If DECL is a specialization of some template, return the most general such template. For example, given: template <class T> struct S { template <class U> void f(U); }; if TMPL is `template <class U> void S<int>::f(U)' this will return the full template. This function will not trace past partial specializations, however. For example, given in addition: template <class T> struct S<T*> { template <class U> void f(U); }; if TMPL is `template <class U> void S<int*>::f(U)' this will return `template <class T> template <class U> S<T*>::f(U)'. */ tree most_general_template (decl) tree decl; { while (DECL_TEMPLATE_INFO (decl)) decl = DECL_TI_TEMPLATE (decl); return decl; } /* Return the most specialized of the class template specializations of TMPL which can produce an instantiation matching ARGS, or error_mark_node if the choice is ambiguous. */ tree most_specialized_class (tmpl, args) tree tmpl; tree args; { tree list = NULL_TREE; tree t; tree champ; int fate; tmpl = most_general_template (tmpl); for (t = DECL_TEMPLATE_SPECIALIZATIONS (tmpl); t; t = TREE_CHAIN (t)) { tree spec_args = get_class_bindings (TREE_VALUE (t), TREE_PURPOSE (t), args); if (spec_args) { list = decl_tree_cons (TREE_PURPOSE (t), TREE_VALUE (t), list); TREE_TYPE (list) = TREE_TYPE (t); } } if (! list) return NULL_TREE; t = list; champ = t; t = TREE_CHAIN (t); for (; t; t = TREE_CHAIN (t)) { fate = more_specialized_class (champ, t); if (fate == 1) ; else { if (fate == 0) { t = TREE_CHAIN (t); if (! t) return error_mark_node; } champ = t; } } for (t = list; t && t != champ; t = TREE_CHAIN (t)) { fate = more_specialized_class (champ, t); if (fate != 1) return error_mark_node; } return champ; } /* called from the parser. */ void do_decl_instantiation (declspecs, declarator, storage) tree declspecs, declarator, storage; { tree decl = grokdeclarator (declarator, declspecs, NORMAL, 0, NULL_TREE); tree result = NULL_TREE; int extern_p = 0; if (! DECL_LANG_SPECIFIC (decl)) { cp_error ("explicit instantiation of non-template `%#D'", decl); return; } else if (TREE_CODE (decl) == VAR_DECL) { /* There is an asymmetry here in the way VAR_DECLs and FUNCTION_DECLs are handled by grokdeclarator. In the case of the latter, the DECL we get back will be marked as a template instantiation, and the appropriate DECL_TEMPLATE_INFO will be set up. This does not happen for VAR_DECLs so we do the lookup here. Probably, grokdeclarator should handle VAR_DECLs as it currently handles FUNCTION_DECLs. */ result = lookup_field (DECL_CONTEXT (decl), DECL_NAME (decl), 0, 0); if (result && TREE_CODE (result) != VAR_DECL) { cp_error ("no matching template for `%D' found", result); return; } } else if (TREE_CODE (decl) != FUNCTION_DECL) { cp_error ("explicit instantiation of `%#D'", decl); return; } else result = decl; /* Check for various error cases. Note that if the explicit instantiation is legal the RESULT will currently be marked as an *implicit* instantiation; DECL_EXPLICIT_INSTANTIATION is not set until we get here. */ if (DECL_TEMPLATE_SPECIALIZATION (result)) { /* [temp.spec] No program shall both explicitly instantiate and explicitly specialize a template. */ cp_error ("explicit instantiation of `%#D' after", result); cp_error_at ("explicit specialization here", result); return; } else if (DECL_EXPLICIT_INSTANTIATION (result)) { /* [temp.spec] No program shall explicitly instantiate any template more than once. We check DECL_INTERFACE_KNOWN so as not to complain when the first instantiation was `extern' and the second is not, and EXTERN_P for the opposite case. */ if (DECL_INTERFACE_KNOWN (result) && !extern_p) cp_error ("duplicate explicit instantiation of `%#D'", result); /* If we've already instantiated the template, just return now. */ if (DECL_INTERFACE_KNOWN (result)) return; } else if (!DECL_IMPLICIT_INSTANTIATION (result)) { cp_error ("no matching template for `%D' found", result); return; } else if (!DECL_TEMPLATE_INFO (result)) { cp_pedwarn ("explicit instantiation of non-template `%#D'", result); return; } if (flag_external_templates) return; if (storage == NULL_TREE) ; else if (storage == ridpointers[(int) RID_EXTERN]) { if (pedantic) cp_pedwarn ("ANSI C++ forbids the use of `extern' on explicit instantiations"); extern_p = 1; } else cp_error ("storage class `%D' applied to template instantiation", storage); SET_DECL_EXPLICIT_INSTANTIATION (result); mark_decl_instantiated (result, extern_p); repo_template_instantiated (result, extern_p); if (! extern_p) instantiate_decl (result); } void mark_class_instantiated (t, extern_p) tree t; int extern_p; { SET_CLASSTYPE_EXPLICIT_INSTANTIATION (t); SET_CLASSTYPE_INTERFACE_KNOWN (t); CLASSTYPE_INTERFACE_ONLY (t) = extern_p; CLASSTYPE_VTABLE_NEEDS_WRITING (t) = ! extern_p; TYPE_DECL_SUPPRESS_DEBUG (TYPE_NAME (t)) = extern_p; if (! extern_p) { CLASSTYPE_DEBUG_REQUESTED (t) = 1; rest_of_type_compilation (t, 1); } } void do_type_instantiation (t, storage) tree t, storage; { int extern_p = 0; int nomem_p = 0; int static_p = 0; if (TREE_CODE (t) == TYPE_DECL) t = TREE_TYPE (t); if (! CLASS_TYPE_P (t) || ! CLASSTYPE_TEMPLATE_INFO (t)) { cp_error ("explicit instantiation of non-template type `%T'", t); return; } complete_type (t); /* With -fexternal-templates, explicit instantiations are treated the same as implicit ones. */ if (flag_external_templates) return; if (TYPE_SIZE (t) == NULL_TREE) { cp_error ("explicit instantiation of `%#T' before definition of template", t); return; } if (storage != NULL_TREE) { if (pedantic) cp_pedwarn("ANSI C++ forbids the use of `%s' on explicit instantiations", IDENTIFIER_POINTER (storage)); if (storage == ridpointers[(int) RID_INLINE]) nomem_p = 1; else if (storage == ridpointers[(int) RID_EXTERN]) extern_p = 1; else if (storage == ridpointers[(int) RID_STATIC]) static_p = 1; else { cp_error ("storage class `%D' applied to template instantiation", storage); extern_p = 0; } } if (CLASSTYPE_TEMPLATE_SPECIALIZATION (t)) { /* [temp.spec] No program shall both explicitly instantiate and explicitly specialize a template. */ cp_error ("explicit instantiation of `%#T' after", t); cp_error_at ("explicit specialization here", t); return; } else if (CLASSTYPE_EXPLICIT_INSTANTIATION (t)) { /* [temp.spec] No program shall explicitly instantiate any template more than once. If CLASSTYPE_INTERFACE_ONLY, then the first explicit instantiation was `extern', and if EXTERN_P then the second is. Both cases are OK. */ if (!CLASSTYPE_INTERFACE_ONLY (t) && !extern_p) cp_error ("duplicate explicit instantiation of `%#T'", t); /* If we've already instantiated the template, just return now. */ if (!CLASSTYPE_INTERFACE_ONLY (t)) return; } mark_class_instantiated (t, extern_p); repo_template_instantiated (t, extern_p); if (nomem_p) return; { tree tmp; /* In contrast to implicit instantiation, where only the declarations, and not the definitions, of members are instantiated, we have here: [temp.explicit] The explicit instantiation of a class template specialization implies the instantiation of all of its members not previously explicitly specialized in the translation unit containing the explicit instantiation. Of course, we can't instantiate member template classes, since we don't have any arguments for them. Note that the standard is unclear on whether the instatiation of the members are *explicit* instantiations or not. We choose to be generous, and not set DECL_EXPLICIT_INSTANTIATION. Therefore, we allow the explicit instantiation of a class where some of the members have no definition in the current translation unit. */ if (! static_p) for (tmp = TYPE_METHODS (t); tmp; tmp = TREE_CHAIN (tmp)) if (TREE_CODE (tmp) == FUNCTION_DECL && DECL_TEMPLATE_INSTANTIATION (tmp)) { mark_decl_instantiated (tmp, extern_p); repo_template_instantiated (tmp, extern_p); if (! extern_p) instantiate_decl (tmp); } for (tmp = TYPE_FIELDS (t); tmp; tmp = TREE_CHAIN (tmp)) if (TREE_CODE (tmp) == VAR_DECL && DECL_TEMPLATE_INSTANTIATION (tmp)) { mark_decl_instantiated (tmp, extern_p); repo_template_instantiated (tmp, extern_p); if (! extern_p) instantiate_decl (tmp); } for (tmp = CLASSTYPE_TAGS (t); tmp; tmp = TREE_CHAIN (tmp)) if (IS_AGGR_TYPE (TREE_VALUE (tmp)) && !uses_template_parms (CLASSTYPE_TI_ARGS (TREE_VALUE (tmp)))) do_type_instantiation (TYPE_MAIN_DECL (TREE_VALUE (tmp)), storage); } } /* Given a function DECL, which is a specialization of TMPL, modify DECL to be a re-instantiation of TMPL with the same template arguments. TMPL should be the template into which tsubst'ing should occur for DECL, not the most general template. One reason for doing this is a scenario like this: template <class T> void f(const T&, int i); void g() { f(3, 7); } template <class T> void f(const T& t, const int i) { } Note that when the template is first instantiated, with instantiate_template, the resulting DECL will have no name for the first parameter, and the wrong type for the second. So, when we go to instantiate the DECL, we regenerate it. */ void regenerate_decl_from_template (decl, tmpl) tree decl; tree tmpl; { tree args; tree code_pattern; tree new_decl; tree gen_tmpl; int unregistered; args = DECL_TI_ARGS (decl); code_pattern = DECL_TEMPLATE_RESULT (tmpl); /* Unregister the specialization so that when we tsubst we will not just return DECL. We don't have to unregister DECL from TMPL because if would only be registered there if it were a partial instantiation of a specialization, which it isn't: it's a full instantiation. */ gen_tmpl = most_general_template (tmpl); unregistered = unregister_specialization (decl, gen_tmpl); /* If the DECL was not unregistered then something peculiar is happening: we created a specialization but did not call register_specialization for it. */ my_friendly_assert (unregistered, 0); if (TREE_CODE (decl) == VAR_DECL) /* Make sure that we can see identifiers, and compute access correctly, for the class members used in the declaration of this static variable. */ pushclass (DECL_CONTEXT (decl), 2); /* Do the substitution to get the new declaration. */ new_decl = tsubst (code_pattern, args, NULL_TREE); if (TREE_CODE (decl) == VAR_DECL) { /* Set up DECL_INITIAL, since tsubst doesn't. */ DECL_INITIAL (new_decl) = tsubst_expr (DECL_INITIAL (code_pattern), args, DECL_TI_TEMPLATE (decl)); /* Pop the class context we pushed above. */ popclass (1); } if (TREE_CODE (decl) == FUNCTION_DECL) { /* Convince duplicate_decls to use the DECL_ARGUMENTS from the new decl. */ DECL_INITIAL (new_decl) = error_mark_node; /* And don't complain about a duplicate definition. */ DECL_INITIAL (decl) = NULL_TREE; } /* The immediate parent of the new template is still whatever it was before, even though tsubst sets DECL_TI_TEMPLATE up as the most general template. We also reset the DECL_ASSEMBLER_NAME since tsubst always calculates the name as if the function in question were really a template instance, and sometimes, with friend functions, this is not so. See tsubst_friend_function for details. */ DECL_TI_TEMPLATE (new_decl) = DECL_TI_TEMPLATE (decl); DECL_ASSEMBLER_NAME (new_decl) = DECL_ASSEMBLER_NAME (decl); DECL_RTL (new_decl) = DECL_RTL (decl); /* Call duplicate decls to merge the old and new declarations. */ duplicate_decls (new_decl, decl); /* Now, re-register the specialization. */ register_specialization (decl, gen_tmpl, args); } /* Produce the definition of D, a _DECL generated from a template. */ tree instantiate_decl (d) tree d; { tree tmpl = DECL_TI_TEMPLATE (d); tree args = DECL_TI_ARGS (d); tree td; tree code_pattern; tree spec; tree gen_tmpl; int nested = in_function_p (); int pattern_defined; int line = lineno; char *file = input_filename; /* This function should only be used to instantiate templates for functions and static member variables. */ my_friendly_assert (TREE_CODE (d) == FUNCTION_DECL || TREE_CODE (d) == VAR_DECL, 0); if (DECL_TEMPLATE_INSTANTIATED (d)) /* D has already been instantiated. It might seem reasonable to check whether or not D is an explict instantiation, and, if so, stop here. But when an explicit instantiation is deferred until the end of the compilation, DECL_EXPLICIT_INSTANTIATION is set, even though we still need to do the instantiation. */ return d; /* If we already have a specialization of this declaration, then there's no reason to instantiate it. Note that retrieve_specialization gives us both instantiations and specializations, so we must explicitly check DECL_TEMPLATE_SPECIALIZATION. */ gen_tmpl = most_general_template (tmpl); spec = retrieve_specialization (gen_tmpl, args); if (spec != NULL_TREE && DECL_TEMPLATE_SPECIALIZATION (spec)) return spec; /* This needs to happen before any tsubsting. */ if (! push_tinst_level (d)) return d; /* Set TD to the template whose DECL_TEMPLATE_RESULT is the pattern for the instantiation. This is not always the most general template. Consider, for example: template <class T> struct S { template <class U> void f(); template <> void f<int>(); }; and an instantiation of S<double>::f<int>. We want TD to be the specialization S<T>::f<int>, not the more general S<T>::f<U>. */ td = tmpl; for (td = tmpl; /* An instantiation cannot have a definition, so we need a more general template. */ DECL_TEMPLATE_INSTANTIATION (td) /* We must also deal with friend templates. Given: template <class T> struct S { template <class U> friend void f() {}; }; S<int>::f<U> say, is not an instantiation of S<T>::f<U>, so far as the language is concerned, but that's still where we get the pattern for the instantiation from. On ther hand, if the definition comes outside the class, say: template <class T> struct S { template <class U> friend void f(); }; template <class U> friend void f() {} we don't need to look any further. That's what the check for DECL_INITIAL is for. */ || (TREE_CODE (d) == FUNCTION_DECL && DECL_FRIEND_PSEUDO_TEMPLATE_INSTANTIATION (td) && !DECL_INITIAL (DECL_TEMPLATE_RESULT (td))); ) { /* The present template, TD, should not be a definition. If it were a definition, we should be using it! Note that we cannot restructure the loop to just keep going until we find a template with a definition, since that might go too far if a specialization was declared, but not defined. */ my_friendly_assert (!(TREE_CODE (d) == VAR_DECL && !DECL_IN_AGGR_P (DECL_TEMPLATE_RESULT (td))), 0); /* Fetch the more general template. */ td = DECL_TI_TEMPLATE (td); } code_pattern = DECL_TEMPLATE_RESULT (td); if (TREE_CODE (d) == FUNCTION_DECL) pattern_defined = (DECL_INITIAL (code_pattern) != NULL_TREE); else pattern_defined = ! DECL_IN_AGGR_P (code_pattern); push_to_top_level (); lineno = DECL_SOURCE_LINE (d); input_filename = DECL_SOURCE_FILE (d); if (pattern_defined) { repo_template_used (d); if (flag_external_templates && ! DECL_INTERFACE_KNOWN (d)) { if (flag_alt_external_templates) { if (interface_unknown) warn_if_unknown_interface (d); } else if (DECL_INTERFACE_KNOWN (code_pattern)) { DECL_INTERFACE_KNOWN (d) = 1; DECL_NOT_REALLY_EXTERN (d) = ! DECL_EXTERNAL (code_pattern); } else warn_if_unknown_interface (code_pattern); } if (at_eof) import_export_decl (d); } /* Reject all external templates except inline functions. */ if (DECL_INTERFACE_KNOWN (d) && ! DECL_NOT_REALLY_EXTERN (d) && ! (TREE_CODE (d) == FUNCTION_DECL && DECL_INLINE (d))) goto out; if (TREE_CODE (d) == VAR_DECL && TREE_READONLY (d) && DECL_INITIAL (d) == NULL_TREE && DECL_INITIAL (code_pattern) != NULL_TREE) /* We need to set up DECL_INITIAL regardless of pattern_defined if the variable is a static const initialized in the class body. */; else if (! pattern_defined || (! (TREE_CODE (d) == FUNCTION_DECL && DECL_INLINE (d) && nested) && ! at_eof)) { /* Defer all templates except inline functions used in another function. We restore the source position here because it's used by add_pending_template. */ lineno = line; input_filename = file; if (at_eof && !pattern_defined && DECL_EXPLICIT_INSTANTIATION (d)) /* [temp.explicit] The definition of a non-exported function template, a non-exported member function template, or a non-exported member function or static data member of a class template shall be present in every translation unit in which it is explicitly instantiated. */ cp_error ("explicit instantiation of `%D' but no definition available", d); add_pending_template (d); goto out; } regenerate_decl_from_template (d, td); DECL_TEMPLATE_INSTANTIATED (d) = 1; /* We already set the file and line above. Reset them now in case they changed as a result of calling regenerate_decl_from_template. */ lineno = DECL_SOURCE_LINE (d); input_filename = DECL_SOURCE_FILE (d); if (TREE_CODE (d) == VAR_DECL) { DECL_IN_AGGR_P (d) = 0; if (DECL_INTERFACE_KNOWN (d)) DECL_EXTERNAL (d) = ! DECL_NOT_REALLY_EXTERN (d); else { DECL_EXTERNAL (d) = 1; DECL_NOT_REALLY_EXTERN (d) = 1; } cp_finish_decl (d, DECL_INITIAL (d), NULL_TREE, 0, 0); } else if (TREE_CODE (d) == FUNCTION_DECL) { tree t = DECL_SAVED_TREE (code_pattern); start_function (NULL_TREE, d, NULL_TREE, 1); store_parm_decls (); if (t && TREE_CODE (t) == RETURN_INIT) { store_return_init (TREE_OPERAND (t, 0), tsubst_expr (TREE_OPERAND (t, 1), args, tmpl)); t = TREE_CHAIN (t); } if (t && TREE_CODE (t) == CTOR_INITIALIZER) { current_member_init_list = tsubst_expr_values (TREE_OPERAND (t, 0), args); current_base_init_list = tsubst_expr_values (TREE_OPERAND (t, 1), args); t = TREE_CHAIN (t); } setup_vtbl_ptr (); /* Always keep the BLOCK node associated with the outermost pair of curly braces of a function. These are needed for correct operation of dwarfout.c. */ keep_next_level (); my_friendly_assert (TREE_CODE (t) == COMPOUND_STMT, 42); tsubst_expr (t, args, tmpl); finish_function (lineno, 0, nested); } out: lineno = line; input_filename = file; pop_from_top_level (); pop_tinst_level (); return d; } static tree tsubst_expr_values (t, argvec) tree t, argvec; { tree first = NULL_TREE; tree *p = &first; for (; t; t = TREE_CHAIN (t)) { tree pur = tsubst_copy (TREE_PURPOSE (t), argvec, NULL_TREE); tree val = tsubst_expr (TREE_VALUE (t), argvec, NULL_TREE); *p = build_tree_list (pur, val); p = &TREE_CHAIN (*p); } return first; } tree last_tree; void add_tree (t) tree t; { last_tree = TREE_CHAIN (last_tree) = t; } void begin_tree () { saved_trees = tree_cons (NULL_TREE, last_tree, saved_trees); last_tree = NULL_TREE; } void end_tree () { my_friendly_assert (saved_trees != NULL_TREE, 0); last_tree = TREE_VALUE (saved_trees); saved_trees = TREE_CHAIN (saved_trees); } /* D is an undefined function declaration in the presence of templates with the same name, listed in FNS. If one of them can produce D as an instantiation, remember this so we can instantiate it at EOF if D has not been defined by that time. */ void add_maybe_template (d, fns) tree d, fns; { tree t; if (DECL_MAYBE_TEMPLATE (d)) return; t = most_specialized (fns, d, NULL_TREE); if (! t) return; if (t == error_mark_node) { cp_error ("ambiguous template instantiation for `%D'", d); return; } *maybe_template_tail = perm_tree_cons (t, d, NULL_TREE); maybe_template_tail = &TREE_CHAIN (*maybe_template_tail); DECL_MAYBE_TEMPLATE (d) = 1; } /* Set CURRENT_ACCESS_SPECIFIER based on the protection of DECL. */ static void set_current_access_from_decl (decl) tree decl; { if (TREE_PRIVATE (decl)) current_access_specifier = access_private_node; else if (TREE_PROTECTED (decl)) current_access_specifier = access_protected_node; else current_access_specifier = access_public_node; } /* Instantiate an enumerated type. TAG is the template type, NEWTAG is the instantiation (which should have been created with start_enum) and ARGS are the template arguments to use. */ static void tsubst_enum (tag, newtag, args) tree tag; tree newtag; tree args; { tree e; for (e = TYPE_VALUES (tag); e; e = TREE_CHAIN (e)) { tree value; tree elt; /* Note that in a template enum, the TREE_VALUE is the CONST_DECL, not the corresponding INTEGER_CST. */ value = tsubst_expr (DECL_INITIAL (TREE_VALUE (e)), args, NULL_TREE); /* Give this enumeration constant the correct access. */ set_current_access_from_decl (TREE_VALUE (e)); /* Actually build the enumerator itself. */ elt = build_enumerator (TREE_PURPOSE (e), value, newtag); /* We save the enumerators we have built so far in the TYPE_VALUES so that if the enumeration constants for subsequent enumerators involve those for previous ones, tsubst_copy will be able to find them. */ TREE_CHAIN (elt) = TYPE_VALUES (newtag); TYPE_VALUES (newtag) = elt; } finish_enum (newtag); } /* Set the DECL_ASSEMBLER_NAME for DECL, which is a FUNCTION_DECL that is either an instantiation or specialization of a template function. */ static void set_mangled_name_for_template_decl (decl) tree decl; { tree saved_namespace; tree context = NULL_TREE; tree fn_type; tree ret_type; tree parm_types; tree tparms; tree targs; tree tmpl; int parm_depth; my_friendly_assert (TREE_CODE (decl) == FUNCTION_DECL, 0); my_friendly_assert (DECL_TEMPLATE_INFO (decl) != NULL_TREE, 0); /* The names of template functions must be mangled so as to indicate what template is being specialized with what template arguments. For example, each of the following three functions must get different mangled names: void f(int); template <> void f<7>(int); template <> void f<8>(int); */ targs = DECL_TI_ARGS (decl); if (uses_template_parms (targs)) /* This DECL is for a partial instantiation. There's no need to mangle the name of such an entity. */ return; tmpl = most_general_template (DECL_TI_TEMPLATE (decl)); tparms = DECL_TEMPLATE_PARMS (tmpl); parm_depth = TMPL_PARMS_DEPTH (tparms); /* There should be as many levels of arguments as there are levels of parameters. */ my_friendly_assert (parm_depth == TMPL_ARGS_DEPTH (targs), 0); /* We now compute the PARMS and RET_TYPE to give to build_decl_overload_real. The PARMS and RET_TYPE are the parameter and return types of the template, after all but the innermost template arguments have been substituted, not the parameter and return types of the function DECL. For example, given: template <class T> T f(T); both PARMS and RET_TYPE should be `T' even if DECL is `int f(int)'. A more subtle example is: template <class T> struct S { template <class U> void f(T, U); } Here, if DECL is `void S<int>::f(int, double)', PARMS should be {int, U}. Thus, the args that we want to subsitute into the return and parameter type for the function are those in TARGS, with the innermost level omitted. */ fn_type = TREE_TYPE (tmpl); if (DECL_STATIC_FUNCTION_P (decl)) context = DECL_CLASS_CONTEXT (decl); if (parm_depth == 1) /* No substitution is necessary. */ ; else { int i; tree partial_args; /* Replace the innermost level of the TARGS with NULL_TREEs to let tsubst know not to subsitute for those parameters. */ partial_args = make_temp_vec (TREE_VEC_LENGTH (targs)); for (i = 1; i < TMPL_ARGS_DEPTH (targs); ++i) SET_TMPL_ARGS_LEVEL (partial_args, i, TMPL_ARGS_LEVEL (targs, i)); SET_TMPL_ARGS_LEVEL (partial_args, TMPL_ARGS_DEPTH (targs), make_temp_vec (DECL_NTPARMS (tmpl))); /* Now, do the (partial) substitution to figure out the appropriate function type. */ fn_type = tsubst (fn_type, partial_args, NULL_TREE); if (DECL_STATIC_FUNCTION_P (decl)) context = tsubst (context, partial_args, NULL_TREE); /* Substitute into the template parameters to obtain the real innermost set of parameters. This step is important if the innermost set of template parameters contains value parameters whose types depend on outer template parameters. */ TREE_VEC_LENGTH (partial_args)--; tparms = tsubst_template_parms (tparms, partial_args); } /* Now, get the innermost parameters and arguments, and figure out the parameter and return types. */ tparms = INNERMOST_TEMPLATE_PARMS (tparms); targs = innermost_args (targs); ret_type = TREE_TYPE (fn_type); parm_types = TYPE_ARG_TYPES (fn_type); /* For a static member function, we generate a fake `this' pointer, for the purposes of mangling. This indicates of which class the function is a member. Because of: [class.static] There shall not be a static and a nonstatic member function with the same name and the same parameter types we don't have to worry that this will result in a clash with a non-static member function. */ if (DECL_STATIC_FUNCTION_P (decl)) parm_types = hash_tree_chain (build_pointer_type (context), parm_types); /* There should be the same number of template parameters as template arguments. */ my_friendly_assert (TREE_VEC_LENGTH (tparms) == TREE_VEC_LENGTH (targs), 0); /* If the template is in a namespace, we need to put that into the mangled name. Unfortunately, build_decl_overload_real does not get the decl to mangle, so it relies on the current namespace. Therefore, we set that here temporarily. */ my_friendly_assert (TREE_CODE_CLASS (TREE_CODE (decl)) == 'd', 980702); saved_namespace = current_namespace; current_namespace = CP_DECL_CONTEXT (decl); /* Actually set the DCL_ASSEMBLER_NAME. */ DECL_ASSEMBLER_NAME (decl) = build_decl_overload_real (DECL_NAME (decl), parm_types, ret_type, tparms, targs, DECL_FUNCTION_MEMBER_P (decl) + DECL_CONSTRUCTOR_P (decl)); /* Restore the previously active namespace. */ current_namespace = saved_namespace; }