From: Jason Merrill Date: Fri, 1 Apr 2022 13:01:30 +0000 (-0400) Subject: Revert "c++: delayed parse DMI [PR96645]" X-Git-Tag: basepoints/gcc-13~353 X-Git-Url: https://gcc.gnu.org/git/?a=commitdiff_plain;h=86d8e0c0652ef5236a460b75c25e4f7093cc0651;p=gcc.git Revert "c++: delayed parse DMI [PR96645]" The breakage from r12-7804 (in WebKit, particularly) is more of a can of worms than I think we can address in GCC 12, so let's return to the GCC 11 status quo for now and try again in stage 1. I think the change was correct for the current standard, but the standard needs a fix in this area; this is CWG issue 2335. PR c++/96645 This reverts commits r12-7804 and r12-7929. --- diff --git a/gcc/cp/class.cc b/gcc/cp/class.cc index c75b889cb84d..40e17140db5e 100644 --- a/gcc/cp/class.cc +++ b/gcc/cp/class.cc @@ -5415,11 +5415,10 @@ type_has_user_provided_or_explicit_constructor (tree t) /* Returns true iff class T has a non-user-provided (i.e. implicitly declared or explicitly defaulted in the class body) default - constructor. If SYNTH, only return true if it hasn't been - implicitly defined yet. */ + constructor. */ -static bool -type_has_non_user_provided_default_constructor_1 (tree t, bool synth) +bool +type_has_non_user_provided_default_constructor (tree t) { if (!TYPE_HAS_DEFAULT_CONSTRUCTOR (t)) return false; @@ -5432,28 +5431,12 @@ type_has_non_user_provided_default_constructor_1 (tree t, bool synth) if (TREE_CODE (fn) == FUNCTION_DECL && default_ctor_p (fn) && !user_provided_p (fn)) - { - if (synth) - return !DECL_INITIAL (fn); - return true; - } + return true; } return false; } -bool -type_has_non_user_provided_default_constructor (tree t) -{ - return type_has_non_user_provided_default_constructor_1 (t, false); -} - -bool -type_has_default_ctor_to_be_synthesized (tree t) -{ - return type_has_non_user_provided_default_constructor_1 (t, true); -} - /* TYPE is being used as a virtual base, and has a non-trivial move assignment. Return true if this is due to there being a user-provided move assignment in TYPE or one of its subobjects; if there isn't, then diff --git a/gcc/cp/cp-tree.h b/gcc/cp/cp-tree.h index 02734a42f1b8..2f718852ac18 100644 --- a/gcc/cp/cp-tree.h +++ b/gcc/cp/cp-tree.h @@ -6720,7 +6720,6 @@ extern tree in_class_defaulted_default_constructor (tree); extern bool user_provided_p (tree); extern bool type_has_user_provided_constructor (tree); extern bool type_has_non_user_provided_default_constructor (tree); -extern bool type_has_default_ctor_to_be_synthesized (tree); extern bool vbase_has_user_provided_move_assign (tree); extern tree default_init_uninitialized_part (tree); extern bool trivial_default_constructor_is_constexpr (tree); diff --git a/gcc/cp/method.cc b/gcc/cp/method.cc index e0fe21777302..903ee666ef39 100644 --- a/gcc/cp/method.cc +++ b/gcc/cp/method.cc @@ -2056,28 +2056,6 @@ assignable_expr (tree to, tree from) return r; } -/* An unparsed default member initializer prevents calling a defaulted default - constructor; make checking std::is_constructible ill-formed until the DMI - has been parsed, to avoid caching the wrong value. */ - -static bool -complain_about_unparsed_dmi (tree t) -{ - if (type_has_default_ctor_to_be_synthesized (t) - && TYPE_HAS_COMPLEX_DFLT (t)) - for (tree f = TYPE_FIELDS (t); f; f = DECL_CHAIN (f)) - if (TREE_CODE (f) == FIELD_DECL - && DECL_INITIAL (f) - && TREE_CODE (DECL_INITIAL (f)) == DEFERRED_PARSE) - { - error ("default member initializer for %qD required by %qs before " - "the end of its enclosing class", f, "std::is_constructible"); - inform (location_of (f), "defined here"); - return true; - } - return false; -} - /* The predicate condition for a template specialization is_constructible shall be satisfied if and only if the following variable definition would be well-formed for some invented @@ -2092,8 +2070,6 @@ constructible_expr (tree to, tree from) cp_unevaluated cp_uneval_guard; if (CLASS_TYPE_P (to)) { - if (!from && complain_about_unparsed_dmi (to)) - return error_mark_node; tree ctype = to; vec *args = NULL; if (!TYPE_REF_P (to)) diff --git a/gcc/cp/parser.cc b/gcc/cp/parser.cc index 63c8af1c7229..7e1c777364e7 100644 --- a/gcc/cp/parser.cc +++ b/gcc/cp/parser.cc @@ -2701,8 +2701,6 @@ static tree cp_parser_late_parse_one_default_arg (cp_parser *, tree, tree, tree); static void cp_parser_late_parsing_nsdmi (cp_parser *, tree); -static bool cp_parser_early_parsing_nsdmi - (cp_parser *, tree); static void cp_parser_late_parsing_default_args (cp_parser *, tree); static tree cp_parser_sizeof_operand @@ -27480,8 +27478,7 @@ cp_parser_member_declaration (cp_parser* parser) if (DECL_DECLARES_FUNCTION_P (decl)) cp_parser_save_default_args (parser, STRIP_TEMPLATE (decl)); else if (TREE_CODE (decl) == FIELD_DECL - && DECL_INITIAL (decl) - && !cp_parser_early_parsing_nsdmi (parser, decl)) + && DECL_INITIAL (decl)) /* Add DECL to the queue of NSDMI to be parsed later. */ vec_safe_push (unparsed_nsdmis, decl); } @@ -32295,29 +32292,6 @@ cp_parser_late_parsing_nsdmi (cp_parser *parser, tree field) DECL_INITIAL (field) = def; } -/* If the DEFERRED_PARSE for FIELD is safe to parse immediately, do so. - Returns true if deferred parsing is no longer needed. */ - -static bool -cp_parser_early_parsing_nsdmi (cp_parser *parser, tree field) -{ - tree init = DECL_INITIAL (field); - if (TREE_CODE (init) != DEFERRED_PARSE) - return true; - - cp_token_cache *tokens = DEFPARSE_TOKENS (init); - for (cp_token *p = tokens->first; p != tokens->last; ++p) - if (p->type == CPP_NAME - || p->keyword == RID_THIS - || p->keyword == RID_OPERATOR) - /* There's a name to look up or 'this', give up. */ - return false; - - /* It's trivial, parse now. */ - cp_parser_late_parsing_nsdmi (parser, field); - return true; -} - /* FN is a FUNCTION_DECL which may contains a parameter with an unparsed DEFERRED_PARSE. Parse the default args now. This function assumes that the current scope is the scope in which the default diff --git a/gcc/testsuite/g++.dg/cpp0x/nsdmi10.C b/gcc/testsuite/g++.dg/cpp0x/nsdmi10.C index a965f7bc3334..d8588b7f29ea 100644 --- a/gcc/testsuite/g++.dg/cpp0x/nsdmi10.C +++ b/gcc/testsuite/g++.dg/cpp0x/nsdmi10.C @@ -6,7 +6,7 @@ struct A1 { int y1 = 1; }; - A1(const B1& opts = B1()) {} + A1(const B1& opts = B1()) {} // { dg-error "default member initializer" } }; struct A2 { @@ -14,5 +14,5 @@ struct A2 { int x2, y2 = 1; }; - A2(const B2& opts = B2()) {} + A2(const B2& opts = B2()) {} // { dg-error "default member initializer" } }; diff --git a/gcc/testsuite/g++.dg/ext/is_constructible7.C b/gcc/testsuite/g++.dg/ext/is_constructible7.C deleted file mode 100644 index 013a1df03c6a..000000000000 --- a/gcc/testsuite/g++.dg/ext/is_constructible7.C +++ /dev/null @@ -1,27 +0,0 @@ -// PR c++/96645 -// { dg-do compile { target c++11 } } - -template -struct bool_constant -{ - static constexpr bool value = B; - using type = bool_constant; -}; - -using true_type = bool_constant; - -template -struct is_default_constructible - : bool_constant<__is_constructible(T)> -{ }; - -void testVarStruct() -{ - struct DataWithStruct { - struct A { - int number = 5; // compiles, if remove initialization - }; - - is_default_constructible::type t = true_type{}; - }; -}