From: Patrick Palka Date: Thu, 18 Jul 2024 00:54:14 +0000 (-0400) Subject: c++: diagnose failed qualified lookup into current inst X-Git-Tag: basepoints/gcc-16~7436 X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=313afcfdabeab3e6705ac0bd1273627075be0023;p=thirdparty%2Fgcc.git c++: diagnose failed qualified lookup into current inst When the scope of a qualified name is the current instantiation, and qualified lookup finds nothing at template definition time, then we know it'll find nothing at instantiation time (unless the current instantiation has dependent bases). So such qualified name lookup failure can be diagnosed ahead of time as per [temp.res.general]/6. This patch implements that, for qualified names of the form (where the current instantiation is A): this->non_existent a.non_existent A::non_existent typename A::non_existent It turns out we already optimistically attempt qualified lookup of seemingly every qualified name, even when it's dependently scoped, and then suppress issuing a lookup failure diagnostic after the fact. So implementing this is mostly a matter of restricting the diagnostic suppression to "dependentish" scopes (i.e. dependent scopes or the current instantiation with dependent bases), rather than suppressing for any dependently-typed scope as we currently do. The cp_parser_conversion_function_id change is needed to avoid regressing lookup/using8.C: using A::operator typename A::Nested*; When looking up A::Nested we consider it not dependently scoped since we entered A from cp_parser_conversion_function_id earlier. But this A is the implicit instantiation A not the primary template type A, and so the lookup fails which we now diagnose. This patch works around this by not entering the template scope of a qualified conversion function-id in this case, i.e. if we're in an expression vs declaration context, by seeing if the type already went through finish_template_type with entering_scope=true. gcc/cp/ChangeLog: * decl.cc (make_typename_type): Restrict name lookup failure punting to dependentish_scope_p instead of dependent_type_p. * error.cc (qualified_name_lookup_error): Improve diagnostic when the scope is the current instantiation. * parser.cc (cp_parser_diagnose_invalid_type_name): Likewise. (cp_parser_conversion_function_id): Don't call push_scope on a template scope unless we're in a declaration context. (cp_parser_lookup_name): Restrict name lookup failure punting to dependentish_scope_p instead of depedent_type_p. * semantics.cc (finish_id_expression_1): Likewise. * typeck.cc (finish_class_member_access_expr): Likewise. libstdc++-v3/ChangeLog: * include/experimental/socket (basic_socket_iostream::basic_socket_iostream): Fix typo. * include/tr2/dynamic_bitset (__dynamic_bitset_base::_M_is_proper_subset_of): Likewise. gcc/testsuite/ChangeLog: * g++.dg/cpp0x/alignas18.C: Expect name lookup error for U::X. * g++.dg/cpp0x/forw_enum13.C: Expect name lookup error for D3::A and D4::A. * g++.dg/parse/access13.C: Declare A::E::V to avoid name lookup failure and preserve intent of the test. * g++.dg/parse/enum11.C: Expect extra errors, matching the non-template case. * g++.dg/template/crash123.C: Avoid name lookup failure to preserve intent of the test. * g++.dg/template/crash124.C: Likewise. * g++.dg/template/crash7.C: Adjust expected diagnostics. * g++.dg/template/dtor6.C: Declare A::~A() to avoid name lookup failure and preserve intent of the test. * g++.dg/template/error22.C: Adjust expected diagnostics. * g++.dg/template/static30.C: Avoid name lookup failure to preserve intent of the test. * g++.old-deja/g++.other/decl5.C: Adjust expected diagnostics. * g++.dg/template/non-dependent34.C: New test. Reviewed-by: Jason Merrill --- diff --git a/gcc/cp/decl.cc b/gcc/cp/decl.cc index 66e8a973cce..6b686d75a49 100644 --- a/gcc/cp/decl.cc +++ b/gcc/cp/decl.cc @@ -4536,7 +4536,7 @@ make_typename_type (tree context, tree name, enum tag_types tag_type, else t = NULL_TREE; - if ((!t || TREE_CODE (t) == TREE_LIST) && dependent_type_p (context)) + if ((!t || TREE_CODE (t) == TREE_LIST) && dependentish_scope_p (context)) return build_typename_type (context, name, fullname, tag_type); want_template = TREE_CODE (fullname) == TEMPLATE_ID_EXPR; diff --git a/gcc/cp/error.cc b/gcc/cp/error.cc index e35448f5434..6d99cb27703 100644 --- a/gcc/cp/error.cc +++ b/gcc/cp/error.cc @@ -4714,7 +4714,8 @@ qualified_name_lookup_error (tree scope, tree name, ; /* We already complained. */ else if (TYPE_P (scope)) { - if (!COMPLETE_TYPE_P (scope)) + if (!COMPLETE_TYPE_P (scope) + && !currently_open_class (scope)) error_at (location, "incomplete type %qT used in nested name specifier", scope); else if (TREE_CODE (decl) == TREE_LIST) diff --git a/gcc/cp/parser.cc b/gcc/cp/parser.cc index 1dd0efaf963..efd5d6f29a7 100644 --- a/gcc/cp/parser.cc +++ b/gcc/cp/parser.cc @@ -3888,7 +3888,8 @@ cp_parser_diagnose_invalid_type_name (cp_parser *parser, tree id, else if (TYPE_P (parser->scope)) { auto_diagnostic_group d; - if (!COMPLETE_TYPE_P (parser->scope)) + if (!COMPLETE_TYPE_P (parser->scope) + && !currently_open_class (parser->scope)) cxx_incomplete_type_error (location_of (id), NULL_TREE, parser->scope); else if (cp_lexer_next_token_is (parser->lexer, CPP_LESS)) @@ -17514,7 +17515,10 @@ cp_parser_conversion_function_id (cp_parser* parser) In order to see that `I' is a type-name in the definition, we must be in the scope of `S'. */ - if (saved_scope) + if (saved_scope + /* In A::operator I(), we don't want to enter A if we're + in an expression rather than declaration context. */ + && adjust_type_for_entering_scope (saved_scope) == saved_scope) pushed_scope = push_scope (saved_scope); /* Parse the conversion-type-id. */ type = cp_parser_conversion_type_id (parser); @@ -32219,7 +32223,7 @@ cp_parser_lookup_name (cp_parser *parser, tree name, /* If the scope is a dependent type and either we deferred lookup or we did lookup but didn't find the name, rememeber the name. */ if (decl == error_mark_node && TYPE_P (parser->scope) - && dependent_type_p (parser->scope)) + && dependentish_scope_p (parser->scope)) { if (tag_type) { diff --git a/gcc/cp/semantics.cc b/gcc/cp/semantics.cc index cd3df13772d..c21572e5d7f 100644 --- a/gcc/cp/semantics.cc +++ b/gcc/cp/semantics.cc @@ -4353,7 +4353,7 @@ finish_id_expression_1 (tree id_expression, /* Name lookup failed. */ if (scope && (!TYPE_P (scope) - || (!dependent_type_p (scope) + || (!dependentish_scope_p (scope) && !(identifier_p (id_expression) && IDENTIFIER_CONV_OP_P (id_expression) && dependent_type_p (TREE_TYPE (id_expression)))))) diff --git a/gcc/cp/typeck.cc b/gcc/cp/typeck.cc index 15e5577f670..8df8b871676 100644 --- a/gcc/cp/typeck.cc +++ b/gcc/cp/typeck.cc @@ -3542,7 +3542,7 @@ finish_class_member_access_expr (cp_expr object, tree name, bool template_p, afi.maybe_suggest_accessor (TYPE_READONLY (object_type)); if (member == NULL_TREE) { - if (dependent_type_p (object_type)) + if (dependentish_scope_p (object_type)) /* Try again at instantiation time. */ goto dependent; if (complain & tf_error) diff --git a/gcc/testsuite/g++.dg/cpp0x/alignas18.C b/gcc/testsuite/g++.dg/cpp0x/alignas18.C index 820bdd2d7ca..9c25cd0942b 100644 --- a/gcc/testsuite/g++.dg/cpp0x/alignas18.C +++ b/gcc/testsuite/g++.dg/cpp0x/alignas18.C @@ -3,6 +3,5 @@ template struct S { using U = S; - // FIXME: This is ill-formed; see PR90847. - void fn() alignas(U::X); + void fn() alignas(U::X); // { dg-error "not a member" } }; diff --git a/gcc/testsuite/g++.dg/cpp0x/forw_enum13.C b/gcc/testsuite/g++.dg/cpp0x/forw_enum13.C index b8027f0c28d..37ffad9b956 100644 --- a/gcc/testsuite/g++.dg/cpp0x/forw_enum13.C +++ b/gcc/testsuite/g++.dg/cpp0x/forw_enum13.C @@ -18,13 +18,13 @@ class D2 template class D3 { - enum D3::A { foo } c; // { dg-error "extra qualification not allowed" } + enum D3::A { foo } c; // { dg-error "does not name an enumeration" } }; template class D4 { - enum D4::A { foo } c; // { dg-error "extra qualification not allowed" } + enum D4::A { foo } c; // { dg-error "does not name an enumeration" } }; template @@ -32,7 +32,7 @@ class D5 { class D6 { - enum D6::A { foo } c; // { dg-error "extra qualification not allowed" } + enum D6::A { foo } c; // { dg-error "does not name an enumeration" } }; }; diff --git a/gcc/testsuite/g++.dg/parse/access13.C b/gcc/testsuite/g++.dg/parse/access13.C index 41463c5dde5..ea3cf1111a8 100644 --- a/gcc/testsuite/g++.dg/parse/access13.C +++ b/gcc/testsuite/g++.dg/parse/access13.C @@ -2,6 +2,7 @@ template struct A { + struct E { static int V; }; A::E::V; // { dg-warning "access decl" } enum { V }; // { dg-error "conflicts with a previous decl" } }; diff --git a/gcc/testsuite/g++.dg/parse/enum11.C b/gcc/testsuite/g++.dg/parse/enum11.C index 68ddedbeeec..8bab16a6799 100644 --- a/gcc/testsuite/g++.dg/parse/enum11.C +++ b/gcc/testsuite/g++.dg/parse/enum11.C @@ -2,5 +2,5 @@ template struct A { - enum A::B::C {}; // { dg-error "has not been declared" } + enum A::B::C {}; // { dg-error "" } }; diff --git a/gcc/testsuite/g++.dg/template/crash123.C b/gcc/testsuite/g++.dg/template/crash123.C index 20a49619c6f..20a71cf192b 100644 --- a/gcc/testsuite/g++.dg/template/crash123.C +++ b/gcc/testsuite/g++.dg/template/crash123.C @@ -4,7 +4,7 @@ template struct VI {}; template struct IP { - static const bool r = IP::r; // { dg-error "depth" } + static const bool r = IP::r; // { dg-error "depth" } }; template struct V { diff --git a/gcc/testsuite/g++.dg/template/crash124.C b/gcc/testsuite/g++.dg/template/crash124.C index 4931aa8e9c6..5788ead4630 100644 --- a/gcc/testsuite/g++.dg/template/crash124.C +++ b/gcc/testsuite/g++.dg/template/crash124.C @@ -4,12 +4,12 @@ template struct VI {}; template struct IP { - static const bool r = IP::r; // { dg-error "depth" } + static const bool r = IP::r; // { dg-error "depth" } }; template struct V { - static const bool r = IP::r; + static const bool r = IP::r; VI vi; }; struct X; diff --git a/gcc/testsuite/g++.dg/template/crash7.C b/gcc/testsuite/g++.dg/template/crash7.C index 691628e7878..977b4e454ba 100644 --- a/gcc/testsuite/g++.dg/template/crash7.C +++ b/gcc/testsuite/g++.dg/template/crash7.C @@ -7,9 +7,7 @@ template struct A { - template A(typename A::X) {} // { dg-error "incomplete" } + template A(typename A::X) {} // { dg-error "does not name a type" } }; -// We currently don't give the "no match" error because we don't add the -// invalid constructor template to TYPE_METHODS. -A a; // { dg-message "required" } +A a; // { dg-error "no match" } diff --git a/gcc/testsuite/g++.dg/template/dtor6.C b/gcc/testsuite/g++.dg/template/dtor6.C index a3d778a1ea1..46ebf9ff95f 100644 --- a/gcc/testsuite/g++.dg/template/dtor6.C +++ b/gcc/testsuite/g++.dg/template/dtor6.C @@ -3,6 +3,7 @@ template struct A { static int i; + ~A(); }; template int A::i = { A::~A }; // { dg-error "36:invalid use of non-static member function" } diff --git a/gcc/testsuite/g++.dg/template/error22.C b/gcc/testsuite/g++.dg/template/error22.C index a7e61721113..af87992219b 100644 --- a/gcc/testsuite/g++.dg/template/error22.C +++ b/gcc/testsuite/g++.dg/template/error22.C @@ -4,6 +4,6 @@ struct A { template struct B {}; void ::foo(); // { dg-error "10:invalid use" } - B<&A::foo> b; // { dg-error "incomplete type|template argument" } + B<&A::foo> b; // { dg-error "'foo' is not a member of 'A'|template argument" } }; diff --git a/gcc/testsuite/g++.dg/template/non-dependent34.C b/gcc/testsuite/g++.dg/template/non-dependent34.C new file mode 100644 index 00000000000..4f369ff6b3e --- /dev/null +++ b/gcc/testsuite/g++.dg/template/non-dependent34.C @@ -0,0 +1,44 @@ +// Verify we diagnose failed qualified lookup into the current +// instantiation ahead of time. + +namespace without_dependent_base { +template +struct A { + void f(A& other) { + A::x; // { dg-error "'x' is not a member" } + this->x; // { dg-error "no member named 'x'" } + other.y; // { dg-error "no member named 'y'" } + typename A::type z; // { dg-error "does not name a type" } + + struct B { + void g(A& other) { + A::x; // { dg-error "'x' is not a member" } + this->x; // { dg-error "no member named 'x'" } + other.y; // { dg-error "no member named 'y'" } + typename A::type z; // { dg-error "does not name a type" } + } + }; + } +}; +} + +namespace with_dependent_base { +template +struct A : T { + void f(A& other) { + A::x; + this->x; + other.y; + typename A::type z; + + struct B : T { + void g(A& other) { + A::x; + this->x; + other.y; + typename A::type z; + } + }; + } +}; +} diff --git a/gcc/testsuite/g++.dg/template/static30.C b/gcc/testsuite/g++.dg/template/static30.C index 07dafe23ffa..248f9e9025e 100644 --- a/gcc/testsuite/g++.dg/template/static30.C +++ b/gcc/testsuite/g++.dg/template/static30.C @@ -6,5 +6,5 @@ template struct A static const int i2; }; -template const int A::i1(A::i); -template const int A::i2(3, A::i); // { dg-error "expression list" } +template const int A::i1(A::i1); +template const int A::i2(3, A::i2); // { dg-error "expression list" } diff --git a/gcc/testsuite/g++.old-deja/g++.other/decl5.C b/gcc/testsuite/g++.old-deja/g++.other/decl5.C index 26556aaa7ef..c24957f8bbe 100644 --- a/gcc/testsuite/g++.old-deja/g++.other/decl5.C +++ b/gcc/testsuite/g++.old-deja/g++.other/decl5.C @@ -18,7 +18,7 @@ struct A { struct Z; expand me; // { dg-error "'expand' does not name a type" } void foo(struct A::e); - void foo(struct A::z); // { dg-error "incomplete" } + void foo(struct A::z); // { dg-error "does not name a type" } }; struct Q; diff --git a/libstdc++-v3/include/experimental/socket b/libstdc++-v3/include/experimental/socket index 02c27d66c6a..3fe83a001e6 100644 --- a/libstdc++-v3/include/experimental/socket +++ b/libstdc++-v3/include/experimental/socket @@ -2450,7 +2450,7 @@ inline namespace v1 // XXX ??? ^^^^^^^ { // XXX ??? this->init(std::addressof(_M_sb)); - this->set_rbduf(std::addressof(_M_sb)); + this->set_rdbuf(std::addressof(_M_sb)); } template diff --git a/libstdc++-v3/include/tr2/dynamic_bitset b/libstdc++-v3/include/tr2/dynamic_bitset index 274c4f6a138..f0878d7429e 100644 --- a/libstdc++-v3/include/tr2/dynamic_bitset +++ b/libstdc++-v3/include/tr2/dynamic_bitset @@ -304,7 +304,7 @@ namespace tr2 bool _M_is_proper_subset_of(const __dynamic_bitset_base& __b) const noexcept { - if (this->is_subset_of(__b)) + if (this->_M_is_subset_of(__b)) { if (*this == __b) return false;