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[69.118.112.187]) by smtp.gmail.com with ESMTPSA id r142-20020a37a894000000b00729a26e836esm10198797qke.84.2023.02.13.09.23.45 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Mon, 13 Feb 2023 09:23:45 -0800 (PST) To: gcc-patches@gcc.gnu.org Cc: jason@redhat.com, Patrick Palka Subject: [PATCH 1/2] c++: factor out TYPENAME_TYPE substitution Date: Mon, 13 Feb 2023 12:23:39 -0500 Message-Id: <20230213172340.849204-1-ppalka@redhat.com> X-Mailer: git-send-email 2.39.1.433.g23c56f7bd5 MIME-Version: 1.0 X-Mimecast-Spam-Score: 0 X-Mimecast-Originator: redhat.com X-Spam-Status: No, score=-13.7 required=5.0 tests=BAYES_00, DKIMWL_WL_HIGH, DKIM_SIGNED, DKIM_VALID, DKIM_VALID_AU, DKIM_VALID_EF, GIT_PATCH_0, KAM_SHORT, RCVD_IN_DNSWL_NONE, RCVD_IN_MSPIKE_H2, SPF_HELO_NONE, SPF_NONE, TXREP autolearn=ham autolearn_force=no version=3.4.6 X-Spam-Checker-Version: SpamAssassin 3.4.6 (2021-04-09) on server2.sourceware.org X-BeenThere: gcc-patches@gcc.gnu.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Gcc-patches mailing list List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-Patchwork-Original-From: Patrick Palka via Gcc-patches From: Patrick Palka Reply-To: Patrick Palka Errors-To: gcc-patches-bounces+ouuuleilei=gmail.com@gcc.gnu.org Sender: "Gcc-patches" X-getmail-retrieved-from-mailbox: =?utf-8?q?INBOX?= X-GMAIL-THRID: =?utf-8?q?1757737486875851916?= X-GMAIL-MSGID: =?utf-8?q?1757737486875851916?= [N.B. this is a corrected version of https://gcc.gnu.org/pipermail/gcc-patches/2022-November/607443.html ] This patch factors out the TYPENAME_TYPE case of tsubst into a separate function tsubst_typename_type. It also factors out the two tsubst flags controlling TYPENAME_TYPE substitution, tf_keep_type_decl and tf_tst_ok, into distinct boolean parameters of this new function (and of make_typename_type). Consequently, callers which used to pass tf_tst_ok to tsubst now instead must directly call tsubst_typename_type when appropriate. In a subsequent patch we'll add another flag to tsubst_typename_type controlling whether we want to ignore non-types during the qualified lookup. gcc/cp/ChangeLog: * cp-tree.h (enum tsubst_flags): Remove tf_keep_type_decl and tf_tst_ok. (make_typename_type): Add two trailing boolean parameters defaulted to false. * decl.cc (make_typename_type): Replace uses of tf_keep_type_decl and tf_tst_ok with the corresponding new boolean parameters. * pt.cc (tsubst_typename_type): New, factored out from tsubst and adjusted after removing tf_keep_type_decl and tf_tst_ok. (tsubst_decl) : Conditionally call tsubst_typename_type directly instead of using tf_tst_ok. (tsubst) : Call tsubst_typename_type. (tsubst_copy) : Conditionally call tsubst_typename_type directly instead of using tf_tst_ok. (tsubst_copy_and_build) : Likewise. : Likewise. --- gcc/cp/cp-tree.h | 9 +- gcc/cp/decl.cc | 17 ++-- gcc/cp/pt.cc | 223 +++++++++++++++++++++++++---------------------- 3 files changed, 134 insertions(+), 115 deletions(-) diff --git a/gcc/cp/cp-tree.h b/gcc/cp/cp-tree.h index 06bc64a6b8d..a7c5765fc33 100644 --- a/gcc/cp/cp-tree.h +++ b/gcc/cp/cp-tree.h @@ -5573,8 +5573,7 @@ enum tsubst_flags { tf_error = 1 << 0, /* give error messages */ tf_warning = 1 << 1, /* give warnings too */ tf_ignore_bad_quals = 1 << 2, /* ignore bad cvr qualifiers */ - tf_keep_type_decl = 1 << 3, /* retain typedef type decls - (make_typename_type use) */ + /* 1 << 3 available */ tf_ptrmem_ok = 1 << 4, /* pointers to member ok (internal instantiate_type use) */ tf_user = 1 << 5, /* found template must be a user template @@ -5594,8 +5593,7 @@ enum tsubst_flags { (build_target_expr and friends) */ tf_norm = 1 << 11, /* Build diagnostic information during constraint normalization. */ - tf_tst_ok = 1 << 12, /* Allow a typename-specifier to name - a template (C++17 or later). */ + /* 1 << 12 available */ tf_dguide = 1 << 13, /* Building a deduction guide from a ctor. */ /* Convenient substitution flags combinations. */ tf_warning_or_error = tf_warning | tf_error @@ -6846,7 +6844,8 @@ extern tree declare_local_label (tree); extern tree define_label (location_t, tree); extern void check_goto (tree); extern bool check_omp_return (void); -extern tree make_typename_type (tree, tree, enum tag_types, tsubst_flags_t); +extern tree make_typename_type (tree, tree, enum tag_types, tsubst_flags_t, + bool = false, bool = false); extern tree build_typename_type (tree, tree, tree, tag_types); extern tree make_unbound_class_template (tree, tree, tree, tsubst_flags_t); extern tree make_unbound_class_template_raw (tree, tree, tree); diff --git a/gcc/cp/decl.cc b/gcc/cp/decl.cc index d606b31d7a7..430533606b0 100644 --- a/gcc/cp/decl.cc +++ b/gcc/cp/decl.cc @@ -4228,14 +4228,17 @@ build_typename_type (tree context, tree name, tree fullname, /* Resolve `typename CONTEXT::NAME'. TAG_TYPE indicates the tag provided to name the type. Returns an appropriate type, unless an error occurs, in which case error_mark_node is returned. If we - locate a non-artificial TYPE_DECL and TF_KEEP_TYPE_DECL is set, we + locate a non-artificial TYPE_DECL and KEEP_TYPE_DECL is true, we return that, rather than the _TYPE it corresponds to, in other - cases we look through the type decl. If TF_ERROR is set, complain - about errors, otherwise be quiet. */ + cases we look through the type decl. If TEMPLATE_OK is true and + we found a TEMPLATE_DECL then we return a CTAD placeholder for the + TEMPLATE_DECL. If TF_ERROR is set, complain about errors, otherwise + be quiet. */ tree make_typename_type (tree context, tree name, enum tag_types tag_type, - tsubst_flags_t complain) + tsubst_flags_t complain, bool keep_type_decl /* = false */, + bool template_ok /* = false */) { tree fullname; tree t; @@ -4352,8 +4355,8 @@ make_typename_type (tree context, tree name, enum tag_types tag_type, } if (!want_template && TREE_CODE (t) != TYPE_DECL) { - if ((complain & tf_tst_ok) && cxx_dialect >= cxx17 - && DECL_TYPE_TEMPLATE_P (t)) + if (template_ok && DECL_TYPE_TEMPLATE_P (t) + && cxx_dialect >= cxx17) /* The caller permits this typename-specifier to name a template (because it appears in a CTAD-enabled context). */; else @@ -4383,7 +4386,7 @@ make_typename_type (tree context, tree name, enum tag_types tag_type, t = TYPE_NAME (t); } - if (DECL_ARTIFICIAL (t) || !(complain & tf_keep_type_decl)) + if (DECL_ARTIFICIAL (t) || !keep_type_decl) t = TREE_TYPE (t); maybe_record_typedef_use (t); diff --git a/gcc/cp/pt.cc b/gcc/cp/pt.cc index e89dbf47097..bc47bf15d38 100644 --- a/gcc/cp/pt.cc +++ b/gcc/cp/pt.cc @@ -13949,6 +13949,94 @@ tsubst_aggr_type_1 (tree t, return t; } +/* Substitute ARGS into the TYPENAME_TYPE T. The flag TEMPLATE_OK + is passed to make_typename_type. */ + +static tree +tsubst_typename_type (tree t, tree args, tsubst_flags_t complain, tree in_decl, + bool template_ok = false) +{ + tree ctx = TYPE_CONTEXT (t); + if (TREE_CODE (ctx) == TYPE_PACK_EXPANSION) + { + ctx = tsubst_pack_expansion (ctx, args, complain, in_decl); + if (ctx == error_mark_node + || TREE_VEC_LENGTH (ctx) > 1) + return error_mark_node; + if (TREE_VEC_LENGTH (ctx) == 0) + { + if (complain & tf_error) + error ("%qD is instantiated for an empty pack", + TYPENAME_TYPE_FULLNAME (t)); + return error_mark_node; + } + ctx = TREE_VEC_ELT (ctx, 0); + } + else + ctx = tsubst_aggr_type (ctx, args, complain, in_decl, + /*entering_scope=*/1); + if (ctx == error_mark_node) + return error_mark_node; + + tree f = tsubst_copy (TYPENAME_TYPE_FULLNAME (t), args, + complain, in_decl); + if (f == error_mark_node) + return error_mark_node; + + if (!MAYBE_CLASS_TYPE_P (ctx)) + { + if (complain & tf_error) + error ("%qT is not a class, struct, or union type", ctx); + return error_mark_node; + } + else if (!uses_template_parms (ctx) && !TYPE_BEING_DEFINED (ctx)) + { + /* Normally, make_typename_type does not require that the CTX + have complete type in order to allow things like: + + template struct S { typename S::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 (!complete_type_or_maybe_complain (ctx, NULL_TREE, complain)) + return error_mark_node; + } + + f = make_typename_type (ctx, f, typename_type, complain, + /*keep_type_decl=*/true, template_ok); + if (f == error_mark_node) + return f; + if (TREE_CODE (f) == TYPE_DECL) + { + complain |= tf_ignore_bad_quals; + f = TREE_TYPE (f); + } + + if (TREE_CODE (f) != TYPENAME_TYPE) + { + if (TYPENAME_IS_ENUM_P (t) && TREE_CODE (f) != ENUMERAL_TYPE) + { + if (complain & tf_error) + error ("%qT resolves to %qT, which is not an enumeration type", + t, f); + else + return error_mark_node; + } + else if (TYPENAME_IS_CLASS_P (t) && !CLASS_TYPE_P (f)) + { + if (complain & tf_error) + error ("%qT resolves to %qT, which is not a class type", + t, f); + else + return error_mark_node; + } + } + + return cp_build_qualified_type + (f, cp_type_quals (f) | cp_type_quals (t), complain); +} + /* Map from a FUNCTION_DECL to a vec of default argument instantiations, indexed in reverse order of the parameters. */ @@ -15193,10 +15281,13 @@ tsubst_decl (tree t, tree args, tsubst_flags_t complain) && VAR_HAD_UNKNOWN_BOUND (t) && type != error_mark_node) type = strip_array_domain (type); - tsubst_flags_t tcomplain = complain; - if (VAR_P (t)) - tcomplain |= tf_tst_ok; - type = tsubst (type, args, tcomplain, in_decl); + if (VAR_P (t) + && TREE_CODE (type) == TYPENAME_TYPE + && !typedef_variant_p (type)) + type = tsubst_typename_type (type, args, complain, in_decl, + /*template_ok=*/true); + else + type = tsubst (type, args, complain, in_decl); /* Substituting the type might have recursively instantiated this same alias (c++/86171). */ if (gen_tmpl && DECL_ALIAS_TEMPLATE_P (gen_tmpl) @@ -15889,9 +15980,6 @@ tsubst (tree t, tree args, tsubst_flags_t complain, tree in_decl) bool fndecl_type = (complain & tf_fndecl_type); complain &= ~tf_fndecl_type; - bool tst_ok = (complain & tf_tst_ok); - complain &= ~tf_tst_ok; - if (type && code != TYPENAME_TYPE && code != TEMPLATE_TYPE_PARM @@ -16424,89 +16512,7 @@ tsubst (tree t, tree args, tsubst_flags_t complain, tree in_decl) } case TYPENAME_TYPE: - { - tree ctx = TYPE_CONTEXT (t); - if (TREE_CODE (ctx) == TYPE_PACK_EXPANSION) - { - ctx = tsubst_pack_expansion (ctx, args, complain, in_decl); - if (ctx == error_mark_node - || TREE_VEC_LENGTH (ctx) > 1) - return error_mark_node; - if (TREE_VEC_LENGTH (ctx) == 0) - { - if (complain & tf_error) - error ("%qD is instantiated for an empty pack", - TYPENAME_TYPE_FULLNAME (t)); - return error_mark_node; - } - ctx = TREE_VEC_ELT (ctx, 0); - } - else - ctx = tsubst_aggr_type (ctx, args, complain, in_decl, - /*entering_scope=*/1); - if (ctx == error_mark_node) - return error_mark_node; - - tree f = tsubst_copy (TYPENAME_TYPE_FULLNAME (t), args, - complain, in_decl); - if (f == error_mark_node) - return error_mark_node; - - if (!MAYBE_CLASS_TYPE_P (ctx)) - { - if (complain & tf_error) - error ("%qT is not a class, struct, or union type", ctx); - return error_mark_node; - } - else if (!uses_template_parms (ctx) && !TYPE_BEING_DEFINED (ctx)) - { - /* Normally, make_typename_type does not require that the CTX - have complete type in order to allow things like: - - template struct S { typename S::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 (!complete_type_or_maybe_complain (ctx, NULL_TREE, complain)) - return error_mark_node; - } - - tsubst_flags_t tcomplain = complain | tf_keep_type_decl; - if (tst_ok) - tcomplain |= tf_tst_ok; - f = make_typename_type (ctx, f, typename_type, tcomplain); - if (f == error_mark_node) - return f; - if (TREE_CODE (f) == TYPE_DECL) - { - complain |= tf_ignore_bad_quals; - f = TREE_TYPE (f); - } - - if (TREE_CODE (f) != TYPENAME_TYPE) - { - if (TYPENAME_IS_ENUM_P (t) && TREE_CODE (f) != ENUMERAL_TYPE) - { - if (complain & tf_error) - error ("%qT resolves to %qT, which is not an enumeration type", - t, f); - else - return error_mark_node; - } - else if (TYPENAME_IS_CLASS_P (t) && !CLASS_TYPE_P (f)) - { - if (complain & tf_error) - error ("%qT resolves to %qT, which is not a class type", - t, f); - else - return error_mark_node; - } - } - - return cp_build_qualified_type - (f, cp_type_quals (f) | cp_type_quals (t), complain); - } + return tsubst_typename_type (t, args, complain, in_decl); case UNBOUND_CLASS_TEMPLATE: { @@ -17391,10 +17397,14 @@ tsubst_copy (tree t, tree args, tsubst_flags_t complain, tree in_decl) case IMPLICIT_CONV_EXPR: CASE_CONVERT: { - tsubst_flags_t tcomplain = complain; - if (code == CAST_EXPR) - tcomplain |= tf_tst_ok; - tree type = tsubst (TREE_TYPE (t), args, tcomplain, in_decl); + tree type = TREE_TYPE (t); + if (code == CAST_EXPR + && TREE_CODE (type) == TYPENAME_TYPE + && !typedef_variant_p (type)) + type = tsubst_typename_type (type, args, complain, in_decl, + /*template_ok=*/true); + else + type = tsubst (type, args, complain, in_decl); tree op0 = tsubst_copy (TREE_OPERAND (t, 0), args, complain, in_decl); return build1 (code, type, op0); } @@ -20430,13 +20440,16 @@ tsubst_copy_and_build (tree t, case DYNAMIC_CAST_EXPR: case STATIC_CAST_EXPR: { - tree type; + tree type = TREE_TYPE (t); tree op, r = NULL_TREE; - tsubst_flags_t tcomplain = complain; - if (TREE_CODE (t) == CAST_EXPR) - tcomplain |= tf_tst_ok; - type = tsubst (TREE_TYPE (t), args, tcomplain, in_decl); + if (TREE_CODE (t) == CAST_EXPR + && TREE_CODE (type) == TYPENAME_TYPE + && !typedef_variant_p (type)) + type = tsubst_typename_type (type, args, complain, in_decl, + /*template_ok=*/true); + else + type = tsubst (type, args, complain, in_decl); op = RECUR (TREE_OPERAND (t, 0)); @@ -21421,10 +21434,14 @@ tsubst_copy_and_build (tree t, bool need_copy_p = false; tree r; - tsubst_flags_t tcomplain = complain; - if (COMPOUND_LITERAL_P (t)) - tcomplain |= tf_tst_ok; - tree type = tsubst (TREE_TYPE (t), args, tcomplain, in_decl); + tree type = TREE_TYPE (t); + if (COMPOUND_LITERAL_P (t) + && TREE_CODE (type) == TYPENAME_TYPE + && !typedef_variant_p (type)) + type = tsubst_typename_type (type, args, complain, in_decl, + /*template_ok=*/true); 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[69.118.112.187]) by smtp.gmail.com with ESMTPSA id r142-20020a37a894000000b00729a26e836esm10198797qke.84.2023.02.13.09.23.46 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Mon, 13 Feb 2023 09:23:47 -0800 (PST) To: gcc-patches@gcc.gnu.org Cc: jason@redhat.com, Patrick Palka Subject: [PATCH 2/2] c++: TYPENAME_TYPE lookup ignoring non-types [PR107773] Date: Mon, 13 Feb 2023 12:23:40 -0500 Message-Id: <20230213172340.849204-2-ppalka@redhat.com> X-Mailer: git-send-email 2.39.1.433.g23c56f7bd5 In-Reply-To: <20230213172340.849204-1-ppalka@redhat.com> References: <20230213172340.849204-1-ppalka@redhat.com> MIME-Version: 1.0 X-Mimecast-Spam-Score: 0 X-Mimecast-Originator: redhat.com X-Spam-Status: No, score=-13.7 required=5.0 tests=BAYES_00, DKIMWL_WL_HIGH, DKIM_SIGNED, DKIM_VALID, DKIM_VALID_AU, DKIM_VALID_EF, GIT_PATCH_0, KAM_SHORT, RCVD_IN_DNSWL_NONE, RCVD_IN_MSPIKE_H2, SPF_HELO_NONE, SPF_NONE, TXREP autolearn=ham autolearn_force=no version=3.4.6 X-Spam-Checker-Version: SpamAssassin 3.4.6 (2021-04-09) on server2.sourceware.org X-BeenThere: gcc-patches@gcc.gnu.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Gcc-patches mailing list List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-Patchwork-Original-From: Patrick Palka via Gcc-patches From: Patrick Palka Reply-To: Patrick Palka Errors-To: gcc-patches-bounces+ouuuleilei=gmail.com@gcc.gnu.org Sender: "Gcc-patches" X-getmail-retrieved-from-mailbox: =?utf-8?q?INBOX?= X-GMAIL-THRID: =?utf-8?q?1757737488322206562?= X-GMAIL-MSGID: =?utf-8?q?1757737488322206562?= [N.B. this is a corrected version of https://gcc.gnu.org/pipermail/gcc-patches/2022-November/607443.html ] Currently when resolving a TYPENAME_TYPE for 'typename T::m' via make_typename_type, we consider only type bindings of 'm' and ignore non-type ones. But [temp.res.general]/3 says, in a note, "the usual qualified name lookup ([basic.lookup.qual]) applies even in the presence of 'typename'", and qualified name lookup doesn't discriminate between type and non-type bindings. So when resolving such a TYPENAME_TYPE we want the lookup to consider all bindings. An exception is when we have a TYPENAME_TYPE corresponding to the qualifying scope appearing before the :: scope resolution operator, such as 'T::type' in 'typename T::type::m'. In that case, [basic.lookup.qual]/1 applies, and lookup for such a TYPENAME_TYPE must ignore non-type bindings. So in order to correctly handle all cases, make_typename_type needs an additional flag controlling whether lookup should ignore non-types or not. To that end this patch adds a type_only flag to make_typename_type and defaults it to false (do not ignore non-types). In contexts where we do want to ignore non-types (when substituting into the scope of a TYPENAME_TYPE, SCOPE_REF, USING_DECL) we call tsubst_typename_type directly with type_only=true. Bootstrapped and regtested on x86_64-pc-linux-gnu, does this look OK for trunk? PR c++/107773 gcc/cp/ChangeLog: * cp-tree.h (make_typename_type): Add another boolean parameter that defaults to false. * decl.cc (make_typename_type): Use lookup_member instead of lookup_field. Pass want_type=type_only instead of =false to lookup_member. Generalize format specifier in diagnostic to handle both type and non-type bindings. * pt.cc (tsubst_typename_type): Add another boolean parameter that defaults to false and pass it to make_typename_type. If TYPE_CONTEXT is a TYPENAME_TYPE recurse with type_only=true instead of substituting it via tsubst. (tsubst_decl) : If the scpoe is a TYPENAME_TYPE call tsubst_typename_type directly with type_only=true instead of substituting it via tsubst. (tsubst_qualified_id): Likewise. * search.cc (lookup_member): Document default argument. gcc/testsuite/ChangeLog: * g++.dg/template/typename24.C: New test. * g++.dg/template/typename25.C: New test. * g++.dg/template/typename26.C: New test. --- gcc/cp/cp-tree.h | 2 +- gcc/cp/decl.cc | 14 ++++----- gcc/cp/pt.cc | 24 +++++++++++---- gcc/cp/search.cc | 2 +- gcc/testsuite/g++.dg/template/typename24.C | 18 ++++++++++++ gcc/testsuite/g++.dg/template/typename25.C | 34 ++++++++++++++++++++++ gcc/testsuite/g++.dg/template/typename26.C | 20 +++++++++++++ 7 files changed, 100 insertions(+), 14 deletions(-) create mode 100644 gcc/testsuite/g++.dg/template/typename24.C create mode 100644 gcc/testsuite/g++.dg/template/typename25.C create mode 100644 gcc/testsuite/g++.dg/template/typename26.C diff --git a/gcc/cp/cp-tree.h b/gcc/cp/cp-tree.h index a7c5765fc33..1241dbf8037 100644 --- a/gcc/cp/cp-tree.h +++ b/gcc/cp/cp-tree.h @@ -6845,7 +6845,7 @@ extern tree define_label (location_t, tree); extern void check_goto (tree); extern bool check_omp_return (void); extern tree make_typename_type (tree, tree, enum tag_types, tsubst_flags_t, - bool = false, bool = false); + bool = false, bool = false, bool = false); extern tree build_typename_type (tree, tree, tree, tag_types); extern tree make_unbound_class_template (tree, tree, tree, tsubst_flags_t); extern tree make_unbound_class_template_raw (tree, tree, tree); diff --git a/gcc/cp/decl.cc b/gcc/cp/decl.cc index 430533606b0..c741dc23d99 100644 --- a/gcc/cp/decl.cc +++ b/gcc/cp/decl.cc @@ -4232,13 +4232,14 @@ build_typename_type (tree context, tree name, tree fullname, return that, rather than the _TYPE it corresponds to, in other cases we look through the type decl. If TEMPLATE_OK is true and we found a TEMPLATE_DECL then we return a CTAD placeholder for the - TEMPLATE_DECL. If TF_ERROR is set, complain about errors, otherwise - be quiet. */ + TEMPLATE_DECL. If TYPE_ONLY is true, lookup of NAME in CONTEXT + ignores non-type bindings. If TF_ERROR is set, complain about errors, + otherwise be quiet. */ tree make_typename_type (tree context, tree name, enum tag_types tag_type, tsubst_flags_t complain, bool keep_type_decl /* = false */, - bool template_ok /* = false */) + bool template_ok /* = false */, bool type_only /* = false */) { tree fullname; tree t; @@ -4308,9 +4309,8 @@ make_typename_type (tree context, tree name, enum tag_types tag_type, member of the current instantiation or a non-dependent base; lookup will stop when we hit a dependent base. */ if (!dependent_scope_p (context)) - /* We should only set WANT_TYPE when we're a nested typename type. - Then we can give better diagnostics if we find a non-type. */ - t = lookup_field (context, name, 2, /*want_type=*/true); + t = lookup_member (context, name, /*protect=*/2, + /*want_type=*/type_only, complain); else t = NULL_TREE; @@ -4362,7 +4362,7 @@ make_typename_type (tree context, tree name, enum tag_types tag_type, else { if (complain & tf_error) - error ("% names %q#T, which is not a type", + error ("% names %q#D, which is not a type", context, name, t); return error_mark_node; } diff --git a/gcc/cp/pt.cc b/gcc/cp/pt.cc index bc47bf15d38..27fc0b93484 100644 --- a/gcc/cp/pt.cc +++ b/gcc/cp/pt.cc @@ -13949,12 +13949,12 @@ tsubst_aggr_type_1 (tree t, return t; } -/* Substitute ARGS into the TYPENAME_TYPE T. The flag TEMPLATE_OK - is passed to make_typename_type. */ +/* Substitute ARGS into the TYPENAME_TYPE T. The flags TEMPLATE_OK and + TYPE_ONLY are passed to make_typename_type. */ static tree tsubst_typename_type (tree t, tree args, tsubst_flags_t complain, tree in_decl, - bool template_ok = false) + bool template_ok = false, bool type_only = false) { tree ctx = TYPE_CONTEXT (t); if (TREE_CODE (ctx) == TYPE_PACK_EXPANSION) @@ -13972,6 +13972,10 @@ tsubst_typename_type (tree t, tree args, tsubst_flags_t complain, tree in_decl, } ctx = TREE_VEC_ELT (ctx, 0); } + else if (TREE_CODE (ctx) == TYPENAME_TYPE + && !typedef_variant_p (ctx)) + ctx = tsubst_typename_type (ctx, args, complain, in_decl, + /*template_ok=*/false, /*type_only=*/true); else ctx = tsubst_aggr_type (ctx, args, complain, in_decl, /*entering_scope=*/1); @@ -14004,7 +14008,7 @@ tsubst_typename_type (tree t, tree args, tsubst_flags_t complain, tree in_decl, } f = make_typename_type (ctx, f, typename_type, complain, - /*keep_type_decl=*/true, template_ok); + /*keep_type_decl=*/true, template_ok, type_only); if (f == error_mark_node) return f; if (TREE_CODE (f) == TYPE_DECL) @@ -15094,6 +15098,11 @@ tsubst_decl (tree t, tree args, tsubst_flags_t complain) scope = tsubst_pack_expansion (scope, args, complain, in_decl); variadic_p = true; } + else if (TREE_CODE (scope) == TYPENAME_TYPE + && !typedef_variant_p (scope)) + scope = tsubst_typename_type (scope, args, complain, in_decl, + /*template_ok=*/false, + /*type_only=*/true); else scope = tsubst_copy (scope, args, complain, in_decl); @@ -16885,7 +16894,12 @@ tsubst_qualified_id (tree qualified_id, tree args, scope = TREE_OPERAND (qualified_id, 0); if (args) { - scope = tsubst (scope, args, complain, in_decl); + if (TREE_CODE (scope) == TYPENAME_TYPE + && !typedef_variant_p (scope)) + scope = tsubst_typename_type (scope, args, complain, in_decl, + /*template_ok=*/false, /*type_only=*/true); + else + scope = tsubst (scope, args, complain, in_decl); expr = tsubst_copy (name, args, complain, in_decl); } else diff --git a/gcc/cp/search.cc b/gcc/cp/search.cc index f3f19cafec6..e472a97679d 100644 --- a/gcc/cp/search.cc +++ b/gcc/cp/search.cc @@ -1109,7 +1109,7 @@ build_baselink (tree binfo, tree access_binfo, tree functions, tree optype) tree lookup_member (tree xbasetype, tree name, int protect, bool want_type, - tsubst_flags_t complain, access_failure_info *afi) + tsubst_flags_t complain, access_failure_info *afi /* = NULL */) { tree rval, rval_binfo = NULL_TREE; tree type = NULL_TREE, basetype_path = NULL_TREE; diff --git a/gcc/testsuite/g++.dg/template/typename24.C b/gcc/testsuite/g++.dg/template/typename24.C new file mode 100644 index 00000000000..8b2b3718442 --- /dev/null +++ b/gcc/testsuite/g++.dg/template/typename24.C @@ -0,0 +1,18 @@ +// PR c++/107773 +// Verify lookup for a non-neste TYPENAME_TYPE correctly considers +// non-types. + +struct a { + typedef void get; +}; + +struct b : a { + int get(int i) const; +}; + +template +void f() { + typedef typename T::get type; // { dg-error "'int b::get\\(int\\) const', which is not a type" } +} + +template void f(); diff --git a/gcc/testsuite/g++.dg/template/typename25.C b/gcc/testsuite/g++.dg/template/typename25.C new file mode 100644 index 00000000000..924330ee8d4 --- /dev/null +++ b/gcc/testsuite/g++.dg/template/typename25.C @@ -0,0 +1,34 @@ +// PR c++/107773 +// Verify lookup for TYPENAME_TYPE appearing to the left of the scope (::) +// operator in various contexts correctly ignores non-types. + +struct a { + typedef void type; +}; + +struct c { + struct b : a { + typedef b self; + static int m; + }; + int b; +}; + +template +void f() { + // T::b::type is a TYPENAME_TYPE whose TYPE_CONTEXT is a nested + // TYPENAME_TYPE. + typedef typename T::b::type type; + // T::b::m is a SCOPE_REF whose first operand is a TYPENAME_TYPE. + int m = T::b::m; +} + +template void f(); + +template +struct d : T::b::self { + // The using is a USING_DECL whose USING_DECL_SCOPE is a TYPENAME_TYPE. + using typename T::b::type; +}; + +template struct d; diff --git a/gcc/testsuite/g++.dg/template/typename26.C b/gcc/testsuite/g++.dg/template/typename26.C new file mode 100644 index 00000000000..4e6b764a97b --- /dev/null +++ b/gcc/testsuite/g++.dg/template/typename26.C @@ -0,0 +1,20 @@ +// Example 4 from [temp.res.general]/3. + +struct A { + struct X { }; + int X; +}; +struct B { + struct X { }; +}; +template void f(T t) { + typename T::X x; // { dg-error "'int A::X', which is not a type" } +} +void foo() { + A a; + B b; + f(b); // OK, T::X refers to B::X + // { dg-bogus "" "" { target *-*-* } .-1 } + f(a); // error: T::X refers to the data member A::X not the struct A::X + // { dg-message "required from here" "" { target *-*-* } .-1 } +}