diff options
Diffstat (limited to 'gcc/cp/pt.c')
| -rw-r--r-- | gcc/cp/pt.c | 121 |
1 files changed, 85 insertions, 36 deletions
diff --git a/gcc/cp/pt.c b/gcc/cp/pt.c index da3cd23..1e6c044 100644 --- a/gcc/cp/pt.c +++ b/gcc/cp/pt.c @@ -152,7 +152,6 @@ static tree tsubst_function_type (tree, tree, tsubst_flags_t, tree); static bool check_specialization_scope (void); static tree process_partial_specialization (tree); static void set_current_access_from_decl (tree); -static void check_default_tmpl_args (tree, tree, int, int); static tree get_template_base (tree, tree, tree, tree); static tree try_class_unification (tree, tree, tree, tree); static int coerce_template_template_parms (tree, tree, tsubst_flags_t, @@ -3377,14 +3376,24 @@ process_partial_specialization (tree decl) /* Check that a template declaration's use of default arguments is not invalid. Here, PARMS are the template parameters. IS_PRIMARY is nonzero if DECL is the thing declared by a primary template. - IS_PARTIAL is nonzero if DECL is a partial specialization. */ + IS_PARTIAL is nonzero if DECL is a partial specialization. + -static void -check_default_tmpl_args (tree decl, tree parms, int is_primary, int is_partial) + IS_FRIEND_DECL is nonzero if DECL is a friend function template + declaration (but not a definition); 1 indicates a declaration, 2 + indicates a redeclaration. When IS_FRIEND_DECL=2, no errors are + emitted for extraneous default arguments. + + Returns TRUE if there were no errors found, FALSE otherwise. */ + +bool +check_default_tmpl_args (tree decl, tree parms, int is_primary, + int is_partial, int is_friend_decl) { const char *msg; int last_level_to_check; tree parm_level; + bool no_errors = true; /* [temp.param] @@ -3397,7 +3406,7 @@ check_default_tmpl_args (tree decl, tree parms, int is_primary, int is_partial) /* You can't have a function template declaration in a local scope, nor you can you define a member of a class template in a local scope. */ - return; + return true; if (current_class_type && !TYPE_BEING_DEFINED (current_class_type) @@ -3417,40 +3426,49 @@ check_default_tmpl_args (tree decl, tree parms, int is_primary, int is_partial) declared, so there's no need to do it again now. This function was defined in class scope, but we're processing it's body now that the class is complete. */ - return; - - /* [temp.param] + return true; - If a template-parameter has a default template-argument, all - subsequent template-parameters shall have a default - template-argument supplied. */ - for (parm_level = parms; parm_level; parm_level = TREE_CHAIN (parm_level)) + /* Core issue 226 (C++0x only): the following only applies to class + templates. */ + if (!flag_cpp0x || TREE_CODE (decl) != FUNCTION_DECL) { - tree inner_parms = TREE_VALUE (parm_level); - int ntparms = TREE_VEC_LENGTH (inner_parms); - int seen_def_arg_p = 0; - int i; + /* [temp.param] - for (i = 0; i < ntparms; ++i) - { - tree parm = TREE_VEC_ELT (inner_parms, i); + If a template-parameter has a default template-argument, all + subsequent template-parameters shall have a default + template-argument supplied. */ + for (parm_level = parms; parm_level; parm_level = TREE_CHAIN (parm_level)) + { + tree inner_parms = TREE_VALUE (parm_level); + int ntparms = TREE_VEC_LENGTH (inner_parms); + int seen_def_arg_p = 0; + int i; - if (parm == error_mark_node) - continue; + for (i = 0; i < ntparms; ++i) + { + tree parm = TREE_VEC_ELT (inner_parms, i); - if (TREE_PURPOSE (parm)) - seen_def_arg_p = 1; - else if (seen_def_arg_p) - { - error ("no default argument for %qD", TREE_VALUE (parm)); - /* For better subsequent error-recovery, we indicate that - there should have been a default argument. */ - TREE_PURPOSE (parm) = error_mark_node; - } - } + if (parm == error_mark_node) + continue; + + if (TREE_PURPOSE (parm)) + seen_def_arg_p = 1; + else if (seen_def_arg_p) + { + error ("no default argument for %qD", TREE_VALUE (parm)); + /* For better subsequent error-recovery, we indicate that + there should have been a default argument. */ + TREE_PURPOSE (parm) = error_mark_node; + no_errors = false; + } + } + } } - if (TREE_CODE (decl) != TYPE_DECL || is_partial || !is_primary) + if ((!flag_cpp0x && TREE_CODE (decl) != TYPE_DECL) + || is_partial + || !is_primary + || is_friend_decl) /* For an ordinary class template, default template arguments are allowed at the innermost level, e.g.: template <class T = int> @@ -3461,8 +3479,8 @@ check_default_tmpl_args (tree decl, tree parms, int is_primary, int is_partial) 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. */ + So, for a partial specialization, or for a function template + (in C++98/C++03), we look at all of them. */ ; else /* But, for a primary class template that is not a partial @@ -3471,7 +3489,11 @@ check_default_tmpl_args (tree decl, tree parms, int is_primary, int is_partial) parms = TREE_CHAIN (parms); /* Figure out what error message to issue. */ - if (TREE_CODE (decl) == FUNCTION_DECL) + if (is_friend_decl == 2) + msg = "default template arguments may not be used in function template friend re-declaration"; + else if (is_friend_decl) + msg = "default template arguments may not be used in function template friend declarations"; + else if (TREE_CODE (decl) == FUNCTION_DECL && !flag_cpp0x) msg = "default template arguments may not be used in function templates"; else if (is_partial) msg = "default template arguments may not be used in partial specializations"; @@ -3510,6 +3532,10 @@ check_default_tmpl_args (tree decl, tree parms, int is_primary, int is_partial) { if (msg) { + no_errors = false; + if (is_friend_decl == 2) + return no_errors; + error (msg, decl); msg = 0; } @@ -3525,6 +3551,8 @@ check_default_tmpl_args (tree decl, tree parms, int is_primary, int is_partial) if (msg) msg = "default argument for template parameter for class enclosing %qD"; } + + return no_errors; } /* Worker for push_template_decl_real, called via @@ -3652,7 +3680,7 @@ push_template_decl_real (tree decl, bool is_friend) /* 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); + primary, is_partial, /*is_friend_decl=*/0); /* Ensure that there are no parameter packs in the type of this declaration that have not been expanded. */ @@ -11346,6 +11374,27 @@ type_unification_real (tree tparms, && !saw_undeduced++) goto again; + /* Core issue #226 (C++0x) [temp.deduct]: + + If a template argument has not been deduced, its + default template argument, if any, is used. + + When we are not in C++0x mode (i.e., !flag_cpp0x), + TREE_PURPOSE will either be NULL_TREE or ERROR_MARK_NODE, + so we do not need to explicitly check flag_cpp0x here. */ + if (TREE_PURPOSE (TREE_VEC_ELT (tparms, i))) + { + tree arg = tsubst (TREE_PURPOSE (TREE_VEC_ELT (tparms, i)), + targs, tf_none, NULL_TREE); + if (arg == error_mark_node) + return 1; + else + { + TREE_VEC_ELT (targs, i) = arg; + continue; + } + } + return 2; } |