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Mon, 16 Sep 2024 10:14:27 -0700 (PDT) X-Google-Smtp-Source: AGHT+IHSUZXQ79Jj3wDyGNBfLLTX8Lq8O+Sng9tpx9RYkQfyHA7SxT4kbTC82ow45NKgNn9o/IXLbA== X-Received: by 2002:a05:620a:462b:b0:7a7:faf4:9aab with SMTP id af79cd13be357-7a9e5ee7341mr2579826085a.4.1726506866361; Mon, 16 Sep 2024 10:14:26 -0700 (PDT) Received: from redhat.com ([2603:7000:9500:34a5::1db4]) by smtp.gmail.com with ESMTPSA id af79cd13be357-7ab3e991a9bsm273600385a.45.2024.09.16.10.14.24 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Mon, 16 Sep 2024 10:14:25 -0700 (PDT) Date: Mon, 16 Sep 2024 13:14:23 -0400 From: Marek Polacek To: Jason Merrill Cc: GCC Patches Subject: [PATCH v4] c++: deleting explicitly-defaulted functions [PR116162] Message-ID: References: <20240911165411.459519-1-polacek@redhat.com> <1b4fb2c4-b7c5-46d1-af2e-6046b27222d1@redhat.com> <671cd4bb-c6cc-49e6-bd93-0fb7cc43445f@redhat.com> <0d5c506f-dae2-41c5-9d2b-e4ff9cf9e4a4@redhat.com> MIME-Version: 1.0 In-Reply-To: <0d5c506f-dae2-41c5-9d2b-e4ff9cf9e4a4@redhat.com> User-Agent: Mutt/2.2.12 (2023-09-09) X-Mimecast-Spam-Score: 0 X-Mimecast-Originator: redhat.com Content-Disposition: inline X-Spam-Status: No, score=-12.1 required=5.0 tests=BAYES_00, DKIMWL_WL_HIGH, DKIM_SIGNED, DKIM_VALID, DKIM_VALID_AU, DKIM_VALID_EF, GIT_PATCH_0, RCVD_IN_DNSWL_NONE, RCVD_IN_MSPIKE_H3, RCVD_IN_MSPIKE_WL, 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: 2.1.30 Precedence: list List-Id: Gcc-patches mailing list List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: gcc-patches-bounces~incoming=patchwork.ozlabs.org@gcc.gnu.org On Fri, Sep 13, 2024 at 06:43:06PM +0200, Jason Merrill wrote: > On 9/12/24 3:12 PM, Marek Polacek wrote: > > On Wed, Sep 11, 2024 at 10:25:34PM -0400, Jason Merrill wrote: > > > On 9/11/24 4:08 PM, Marek Polacek wrote: > > > > @@ -6503,10 +6504,17 @@ check_bases_and_members (tree t) > > > > bool fn_const_p = (copy == 2); > > > > if (fn_const_p && !imp_const_p) > > > > - /* If the function is defaulted outside the class, we just > > > > - give the synthesis error. Core Issue #1331 says this is > > > > - no longer ill-formed, it is defined as deleted instead. */ > > > > - DECL_DELETED_FN (fn) = true; > > > > + { > > > > + tree implicit_fn > > > > + = implicitly_declare_fn (kind, DECL_CONTEXT (fn), > > > > + /*const_p=*/false, > > > > + /*pattern_fn=*/NULL_TREE, > > > > + /*inherited_parms=*/NULL_TREE); > > > > + /* If the function is defaulted outside the class, we just > > > > + give the synthesis error. Core Issue #1331 says this is > > > > + no longer ill-formed, it is defined as deleted instead. */ > > > > + maybe_delete_defaulted_fn (fn, implicit_fn); > > > > + } > > > > > > Since we're about to call defaulted_late_check anyway, can we remove all the > > > copy ctor handling here? I don't want to call implicitly_declare_fn twice > > > for the same function. > > > > Yeh, I should've done that; it wasn't complicated in the end. > > > > Bootstrapped/regtested on x86_64-pc-linux-gnu, ok for trunk? > > > > -- >8 -- > > This PR points out the we're not implementing [dcl.fct.def.default] > > properly. Consider e.g. > > > > struct C { > > C(const C&&) = default; > > }; > > > > where we wrongly emit an error, but the move ctor should be just =deleted. > > According to [dcl.fct.def.default], if the type of the special member > > function differs from the type of the corresponding special member function > > that would have been implicitly declared in a way other than as allowed > > by 2.1-4, the function is defined as deleted. There's an exception for > > assignment operators in which case the program is ill-formed. > > > > clang++ has a warning for when we delete an explicitly-defaulted function > > so this patch adds it too. > > Does clang warn by default for template instantiations? I'm concerned about > getting a bunch of noise warnings, but perhaps I'm overestimating how common > that would be. Doesn't look like it. I've added a DECL_TEMPLATE_INSTANTIATION check. But I think we should still emit errors and I suppose pedwarns too. > > +void > > +maybe_delete_defaulted_fn (tree fn, tree implicit_fn) > > +{ > > + if (DECL_ARTIFICIAL (fn) || !DECL_DEFAULTED_IN_CLASS_P (fn)) > > + return; > > + > > + DECL_DELETED_FN (fn) = true; > > + > > + if (!warn_defaulted_fn_deleted) > > + return; > > + > > + auto_diagnostic_group d; > > + const special_function_kind kind = special_function_p (fn); > > + tree parmtype > > + = TREE_VALUE (DECL_XOBJ_MEMBER_FUNCTION_P (fn) > > + ? TREE_CHAIN (TYPE_ARG_TYPES (TREE_TYPE (fn))) > > + : FUNCTION_FIRST_USER_PARMTYPE (fn)); > > + const bool pedwarn_p > > + = (cxx_dialect < cxx20 > > + /* [dcl.fct.def.default] "if F1 is an assignment operator"... */ > > + || (SFK_ASSIGN_P (kind) > > + /* "and the return type of F1 differs from the return type of F2" */ > > + && (!same_type_p (TREE_TYPE (TREE_TYPE (fn)), > > + TREE_TYPE (TREE_TYPE (implicit_fn))) > > + /* "or F1's non-object parameter type is not a reference, > > + the program is ill-formed" */ > > + || !TYPE_REF_P (parmtype)))); > > I'd keep the cases that are ill-formed in C++20 errors; pedwarn for > pre-C++20 in the cases that are warnings in C++20. I'm still a little confused what exactly we want to do here. Does this make sense? Bootstrapped/regtested on x86_64-pc-linux-gnu, ok for trunk? -- >8 -- This PR points out the we're not implementing [dcl.fct.def.default] properly. Consider e.g. struct C { C(const C&&) = default; }; where we wrongly emit an error, but the move ctor should be just =deleted. According to [dcl.fct.def.default], if the type of the special member function differs from the type of the corresponding special member function that would have been implicitly declared in a way other than as allowed by 2.1-4, the function is defined as deleted. There's an exception for assignment operators in which case the program is ill-formed. clang++ has a warning for when we delete an explicitly-defaulted function so this patch adds it too. I'm also downgrading an error to a pedwarn in C++17 since the code compiles in C++20. PR c++/116162 gcc/c-family/ChangeLog: * c.opt (Wdefaulted-function-deleted): New. gcc/cp/ChangeLog: * class.cc (check_bases_and_members): Don't set DECL_DELETED_FN here, leave it to defaulted_late_check. * cp-tree.h (maybe_delete_defaulted_fn): Declare. (defaulted_late_check): Add a tristate parameter. * method.cc (maybe_delete_defaulted_fn): New. (defaulted_late_check): Add a tristate parameter. Call maybe_delete_defaulted_fn instead of giving an error. gcc/ChangeLog: * doc/invoke.texi: Document -Wdefaulted-function-deleted. gcc/testsuite/ChangeLog: * g++.dg/cpp0x/defaulted15.C: Add dg-warning/dg-error. * g++.dg/cpp0x/defaulted51.C: Likewise. * g++.dg/cpp0x/defaulted52.C: Likewise. * g++.dg/cpp0x/defaulted53.C: Likewise. * g++.dg/cpp0x/defaulted54.C: Likewise. * g++.dg/cpp0x/defaulted56.C: Likewise. * g++.dg/cpp0x/defaulted57.C: Likewise. * g++.dg/cpp0x/defaulted58.C: Likewise. * g++.dg/cpp0x/defaulted59.C: Likewise. * g++.dg/cpp0x/defaulted63.C: New test. * g++.dg/cpp0x/defaulted64.C: New test. * g++.dg/cpp0x/defaulted65.C: New test. * g++.dg/cpp0x/defaulted66.C: New test. * g++.dg/cpp23/defaulted1.C: New test. --- gcc/c-family/c.opt | 4 + gcc/cp/class.cc | 27 ++----- gcc/cp/cp-tree.h | 3 +- gcc/cp/method.cc | 95 +++++++++++++++++++++--- gcc/doc/invoke.texi | 9 +++ gcc/testsuite/g++.dg/cpp0x/defaulted15.C | 3 +- gcc/testsuite/g++.dg/cpp0x/defaulted51.C | 2 +- gcc/testsuite/g++.dg/cpp0x/defaulted52.C | 2 +- gcc/testsuite/g++.dg/cpp0x/defaulted53.C | 3 +- gcc/testsuite/g++.dg/cpp0x/defaulted54.C | 1 + gcc/testsuite/g++.dg/cpp0x/defaulted56.C | 6 +- gcc/testsuite/g++.dg/cpp0x/defaulted57.C | 6 +- gcc/testsuite/g++.dg/cpp0x/defaulted58.C | 1 + gcc/testsuite/g++.dg/cpp0x/defaulted59.C | 3 +- gcc/testsuite/g++.dg/cpp0x/defaulted63.C | 39 ++++++++++ gcc/testsuite/g++.dg/cpp0x/defaulted64.C | 27 +++++++ gcc/testsuite/g++.dg/cpp0x/defaulted65.C | 25 +++++++ gcc/testsuite/g++.dg/cpp0x/defaulted66.C | 35 +++++++++ gcc/testsuite/g++.dg/cpp23/defaulted1.C | 23 ++++++ 19 files changed, 274 insertions(+), 40 deletions(-) create mode 100644 gcc/testsuite/g++.dg/cpp0x/defaulted63.C create mode 100644 gcc/testsuite/g++.dg/cpp0x/defaulted64.C create mode 100644 gcc/testsuite/g++.dg/cpp0x/defaulted65.C create mode 100644 gcc/testsuite/g++.dg/cpp0x/defaulted66.C create mode 100644 gcc/testsuite/g++.dg/cpp23/defaulted1.C base-commit: f5448384a2134f32c8733b401440da11bfe69252 diff --git a/gcc/c-family/c.opt b/gcc/c-family/c.opt index ec23249c959..98a35f043c7 100644 --- a/gcc/c-family/c.opt +++ b/gcc/c-family/c.opt @@ -629,6 +629,10 @@ Wdeclaration-missing-parameter-type C ObjC Var(warn_declaration_missing_parameter) Warning Init(1) Warn for missing parameter types in function declarations. +Wdefaulted-function-deleted +C++ ObjC++ Var(warn_defaulted_fn_deleted) Init(1) Warning +Warn when an explicitly defaulted function is deleted. + Wdelete-incomplete C++ ObjC++ Var(warn_delete_incomplete) Init(1) Warning Warn when deleting a pointer to incomplete type. diff --git a/gcc/cp/class.cc b/gcc/cp/class.cc index 950d83b0ea4..646072d4f20 100644 --- a/gcc/cp/class.cc +++ b/gcc/cp/class.cc @@ -6488,27 +6488,14 @@ check_bases_and_members (tree t) for (fn = TYPE_FIELDS (t); fn; fn = DECL_CHAIN (fn)) if (DECL_DECLARES_FUNCTION_P (fn) && !DECL_ARTIFICIAL (fn) - && DECL_DEFAULTED_IN_CLASS_P (fn)) - { + && DECL_DEFAULTED_IN_CLASS_P (fn) /* ...except handle comparisons later, in finish_struct_1. */ - if (special_function_p (fn) == sfk_comparison) - continue; - - int copy = copy_fn_p (fn); - if (copy > 0) - { - bool imp_const_p - = (DECL_CONSTRUCTOR_P (fn) ? !cant_have_const_ctor - : !no_const_asn_ref); - bool fn_const_p = (copy == 2); - - if (fn_const_p && !imp_const_p) - /* If the function is defaulted outside the class, we just - give the synthesis error. Core Issue #1331 says this is - no longer ill-formed, it is defined as deleted instead. */ - DECL_DELETED_FN (fn) = true; - } - defaulted_late_check (fn); + && special_function_p (fn) != sfk_comparison) + { + bool imp_const_p + = (DECL_CONSTRUCTOR_P (fn) ? !cant_have_const_ctor + : !no_const_asn_ref); + defaulted_late_check (fn, imp_const_p); } if (LAMBDA_TYPE_P (t)) diff --git a/gcc/cp/cp-tree.h b/gcc/cp/cp-tree.h index 7baa2ccbe1e..32252e7f32f 100644 --- a/gcc/cp/cp-tree.h +++ b/gcc/cp/cp-tree.h @@ -6929,7 +6929,8 @@ extern bool type_build_ctor_call (tree); extern bool type_build_dtor_call (tree); extern void explain_non_literal_class (tree); extern void inherit_targ_abi_tags (tree); -extern void defaulted_late_check (tree); +extern void maybe_delete_defaulted_fn (tree, tree); +extern void defaulted_late_check (tree, tristate = tristate::unknown ()); extern bool defaultable_fn_check (tree); extern void check_abi_tags (tree); extern tree missing_abi_tags (tree); diff --git a/gcc/cp/method.cc b/gcc/cp/method.cc index 21c06c744c9..0771e508806 100644 --- a/gcc/cp/method.cc +++ b/gcc/cp/method.cc @@ -3509,11 +3509,86 @@ implicitly_declare_fn (special_function_kind kind, tree type, return fn; } +/* Mark an explicitly defaulted function FN as =deleted and warn. + IMPLICIT_FN is the corresponding special member function that + would have been implicitly declared. */ + +void +maybe_delete_defaulted_fn (tree fn, tree implicit_fn) +{ + if (DECL_ARTIFICIAL (fn) || !DECL_DEFAULTED_IN_CLASS_P (fn)) + return; + + DECL_DELETED_FN (fn) = true; + + if (!warn_defaulted_fn_deleted) + return; + + auto_diagnostic_group d; + const special_function_kind kind = special_function_p (fn); + tree parmtype + = TREE_VALUE (DECL_XOBJ_MEMBER_FUNCTION_P (fn) + ? TREE_CHAIN (TYPE_ARG_TYPES (TREE_TYPE (fn))) + : FUNCTION_FIRST_USER_PARMTYPE (fn)); + const bool illformed_p + /* [dcl.fct.def.default] "if F1 is an assignment operator"... */ + = (SFK_ASSIGN_P (kind) + /* "and the return type of F1 differs from the return type of F2" */ + && (!same_type_p (TREE_TYPE (TREE_TYPE (fn)), + TREE_TYPE (TREE_TYPE (implicit_fn))) + /* "or F1's non-object parameter type is not a reference, + the program is ill-formed" */ + || !TYPE_REF_P (parmtype))); + /* Decide if we want to emit a pedwarn, error, or a warning. */ + diagnostic_t diag_kind; + if (cxx_dialect >= cxx20) + diag_kind = illformed_p ? DK_ERROR : DK_WARNING; + else + diag_kind = DK_PEDWARN; + + /* Don't warn for template instantiations. */ + if (DECL_TEMPLATE_INSTANTIATION (fn) && diag_kind == DK_WARNING) + return; + + const char *wmsg; + switch (kind) + { + case sfk_copy_constructor: + wmsg = G_("explicitly defaulted copy constructor is implicitly deleted " + "because its declared type does not match the type of an " + "implicit copy constructor"); + break; + case sfk_move_constructor: + wmsg = G_("explicitly defaulted move constructor is implicitly deleted " + "because its declared type does not match the type of an " + "implicit move constructor"); + break; + case sfk_copy_assignment: + wmsg = G_("explicitly defaulted copy assignment operator is implicitly " + "deleted because its declared type does not match the type " + "of an implicit copy assignment operator"); + break; + case sfk_move_assignment: + wmsg = G_("explicitly defaulted move assignment operator is implicitly " + "deleted because its declared type does not match the type " + "of an implicit move assignment operator"); + break; + default: + gcc_unreachable (); + } + if (emit_diagnostic (diag_kind, DECL_SOURCE_LOCATION (fn), + OPT_Wdefaulted_function_deleted, wmsg)) + inform (DECL_SOURCE_LOCATION (fn), + "expected signature: %qD", implicit_fn); +} + /* Gives any errors about defaulted functions which need to be deferred - until the containing class is complete. */ + until the containing class is complete. IMP_CONST is false or true + if we are called from check_bases_and_members and signals whether + the implicit function has a non-object parameter of type const C&. */ void -defaulted_late_check (tree fn) +defaulted_late_check (tree fn, tristate imp_const/*=tristate::unknown()*/) { /* Complain about invalid signature for defaulted fn. */ tree ctx = DECL_CONTEXT (fn); @@ -3534,8 +3609,14 @@ defaulted_late_check (tree fn) } bool fn_const_p = (copy_fn_p (fn) == 2); + /* "if F2 has a non-object parameter of type const C&, the corresponding + non-object parameter of F1 may be of type C&." But not the other way + around. */ + if (fn_const_p && imp_const.is_false ()) + fn_const_p = false; tree implicit_fn = implicitly_declare_fn (kind, ctx, fn_const_p, - NULL, NULL); + /*pattern_fn=*/NULL_TREE, + /*inherited_parms=*/NULL_TREE); tree eh_spec = TYPE_RAISES_EXCEPTIONS (TREE_TYPE (implicit_fn)); /* Includes special handling for a default xobj operator. */ @@ -3564,13 +3645,7 @@ defaulted_late_check (tree fn) if (!same_type_p (TREE_TYPE (TREE_TYPE (fn)), TREE_TYPE (TREE_TYPE (implicit_fn))) || !compare_fn_params (fn, implicit_fn)) - { - auto_diagnostic_group d; - error ("defaulted declaration %q+D does not match the " - "expected signature", fn); - inform (DECL_SOURCE_LOCATION (fn), - "expected signature: %qD", implicit_fn); - } + maybe_delete_defaulted_fn (fn, implicit_fn); if (DECL_DELETED_FN (implicit_fn)) { diff --git a/gcc/doc/invoke.texi b/gcc/doc/invoke.texi index 511b8c8d311..1d8edc3e485 100644 --- a/gcc/doc/invoke.texi +++ b/gcc/doc/invoke.texi @@ -251,6 +251,7 @@ in the following sections. -Wcomma-subscript -Wconditionally-supported -Wno-conversion-null -Wctad-maybe-unsupported -Wctor-dtor-privacy -Wdangling-reference +-Wno-defaulted-function-deleted -Wno-delete-incomplete -Wdelete-non-virtual-dtor -Wno-deprecated-array-compare -Wdeprecated-copy -Wdeprecated-copy-dtor @@ -4798,6 +4799,14 @@ not caught by reference. @option{-Wcatch-value} is enabled by @option{-Wall}. @item -Wconditionally-supported @r{(C++ and Objective-C++ only)} Warn for conditionally-supported (C++11 [intro.defs]) constructs. +@opindex Wdefaulted-function-deleted +@opindex Wno-defaulted-function-deleted +@item -Wno-defaulted-function-deleted @r{(C++ and Objective-C++ only)} +Warn when an explicitly defaulted function is deleted by the compiler. +That can occur when the function's declared type does not match the type +of the function that would have been implicitly declared. This warning +is enabled by default. + @opindex Wdelete-incomplete @opindex Wno-delete-incomplete @item -Wno-delete-incomplete @r{(C++ and Objective-C++ only)} diff --git a/gcc/testsuite/g++.dg/cpp0x/defaulted15.C b/gcc/testsuite/g++.dg/cpp0x/defaulted15.C index 1e0b3545840..6bd02d74dc3 100644 --- a/gcc/testsuite/g++.dg/cpp0x/defaulted15.C +++ b/gcc/testsuite/g++.dg/cpp0x/defaulted15.C @@ -48,7 +48,8 @@ struct F struct G: public F { - G(const G&) = default; + G(const G&) = default; // { dg-error "implicitly deleted" "" { target c++17_down } } + // { dg-warning "implicitly deleted" "" { target c++20 } .-1 } }; struct H diff --git a/gcc/testsuite/g++.dg/cpp0x/defaulted51.C b/gcc/testsuite/g++.dg/cpp0x/defaulted51.C index 0a7d308707c..d81baa0059d 100644 --- a/gcc/testsuite/g++.dg/cpp0x/defaulted51.C +++ b/gcc/testsuite/g++.dg/cpp0x/defaulted51.C @@ -4,7 +4,7 @@ template struct A { A(); - A(volatile A&) = default; // { dg-error "defaulted" } + A(volatile A&) = default; // { dg-error "defaulted" "" { target c++17_down } } }; struct B diff --git a/gcc/testsuite/g++.dg/cpp0x/defaulted52.C b/gcc/testsuite/g++.dg/cpp0x/defaulted52.C index c617230b493..e6128f40aeb 100644 --- a/gcc/testsuite/g++.dg/cpp0x/defaulted52.C +++ b/gcc/testsuite/g++.dg/cpp0x/defaulted52.C @@ -13,7 +13,7 @@ template struct W { W(); // This should now compile and be =deleted. - W(const W&) = default; + W(const W&) = default; // { dg-error "implicitly deleted" "" { target c++17_down } } T t; }; diff --git a/gcc/testsuite/g++.dg/cpp0x/defaulted53.C b/gcc/testsuite/g++.dg/cpp0x/defaulted53.C index 8147e7e2ad1..cc039672277 100644 --- a/gcc/testsuite/g++.dg/cpp0x/defaulted53.C +++ b/gcc/testsuite/g++.dg/cpp0x/defaulted53.C @@ -14,7 +14,8 @@ struct R struct S { - S& operator=(const S&) = default; + S& operator=(const S&) = default; // { dg-error "implicitly deleted" "" { target c++17_down } } + // { dg-warning "implicitly deleted" "" { target c++20 } .-1 } M m; }; diff --git a/gcc/testsuite/g++.dg/cpp0x/defaulted54.C b/gcc/testsuite/g++.dg/cpp0x/defaulted54.C index f8ddc4e47ce..04cc0cd7eeb 100644 --- a/gcc/testsuite/g++.dg/cpp0x/defaulted54.C +++ b/gcc/testsuite/g++.dg/cpp0x/defaulted54.C @@ -11,6 +11,7 @@ template struct W { W(); W(const W&) = default; // { dg-error "binding" } +// { dg-error "implicitly deleted" "" { target c++17_down } .-1 } T t; }; diff --git a/gcc/testsuite/g++.dg/cpp0x/defaulted56.C b/gcc/testsuite/g++.dg/cpp0x/defaulted56.C index e7ce12c5566..0e36fd293f6 100644 --- a/gcc/testsuite/g++.dg/cpp0x/defaulted56.C +++ b/gcc/testsuite/g++.dg/cpp0x/defaulted56.C @@ -11,12 +11,14 @@ struct S struct T { - constexpr T(volatile T &) = default; // { dg-error "defaulted" } + constexpr T(volatile T &) = default; // { dg-error "defaulted" "" { target c++17_down } } + // { dg-warning "implicitly deleted" "" { target c++20 } .-1 } }; struct U { - constexpr U(const volatile U &) = default; // { dg-error "defaulted" } + constexpr U(const volatile U &) = default; // { dg-error "defaulted" "" { target c++17_down } } + // { dg-warning "implicitly deleted" "" { target c++20 } .-1 } }; struct V diff --git a/gcc/testsuite/g++.dg/cpp0x/defaulted57.C b/gcc/testsuite/g++.dg/cpp0x/defaulted57.C index 37fb7dd6e1d..feca9662b4a 100644 --- a/gcc/testsuite/g++.dg/cpp0x/defaulted57.C +++ b/gcc/testsuite/g++.dg/cpp0x/defaulted57.C @@ -11,12 +11,14 @@ struct S struct T { - T& operator=(volatile T &) = default; // { dg-error "defaulted" } + T& operator=(volatile T &) = default; // { dg-error "defaulted" "" { target c++17_down } } + // { dg-warning "implicitly deleted" "" { target c++20 } .-1 } }; struct U { - U& operator=(const volatile U &) = default; // { dg-error "defaulted" } + U& operator=(const volatile U &) = default; // { dg-error "defaulted" "" { target c++17_down } } + // { dg-warning "implicitly deleted" "" { target c++20 } .-1 } }; struct V diff --git a/gcc/testsuite/g++.dg/cpp0x/defaulted58.C b/gcc/testsuite/g++.dg/cpp0x/defaulted58.C index 920a4ad0c6d..6ddae46cd63 100644 --- a/gcc/testsuite/g++.dg/cpp0x/defaulted58.C +++ b/gcc/testsuite/g++.dg/cpp0x/defaulted58.C @@ -11,6 +11,7 @@ template struct W { W() = default; W& operator=(const W&) = default; // { dg-error "binding" } +// { dg-error "implicitly deleted" "" { target c++17_down } .-1 } T t; }; diff --git a/gcc/testsuite/g++.dg/cpp0x/defaulted59.C b/gcc/testsuite/g++.dg/cpp0x/defaulted59.C index 4f871d7f5b1..26510b4ee33 100644 --- a/gcc/testsuite/g++.dg/cpp0x/defaulted59.C +++ b/gcc/testsuite/g++.dg/cpp0x/defaulted59.C @@ -8,5 +8,6 @@ struct M struct W : public M { - W(const W&) = default; + W(const W&) = default; // { dg-error "implicitly deleted" "" { target c++17_down } } + // { dg-warning "implicitly deleted" "" { target c++20 } .-1 } }; diff --git a/gcc/testsuite/g++.dg/cpp0x/defaulted63.C b/gcc/testsuite/g++.dg/cpp0x/defaulted63.C new file mode 100644 index 00000000000..99f92ff69c5 --- /dev/null +++ b/gcc/testsuite/g++.dg/cpp0x/defaulted63.C @@ -0,0 +1,39 @@ +// PR c++/116162 +// { dg-do compile { target c++11 } } + +struct C0 { + C0(C0&) = default; +}; + +struct C1 { + C1(volatile C1&) = default; // { dg-warning "implicitly deleted" "" { target c++20 } } + // { dg-error "does not match" "" { target c++17_down } .-1 } +}; + +struct C2 { + C2(const C2&) = default; +}; + +struct C3 { + C3(const volatile C3&) = default; // { dg-warning "implicitly deleted" "" { target c++20 } } + // { dg-error "does not match" "" { target c++17_down } .-1 } +}; + +struct M0 { + M0(M0&&) = default; +}; + +struct M1 { + M1(const M1&&) = default; // { dg-warning "implicitly deleted" "" { target c++20 } } + // { dg-error "does not match" "" { target c++17_down } .-1 } +}; + +struct M2 { + M2(volatile M2&&) = default; // { dg-warning "implicitly deleted" "" { target c++20 } } + // { dg-error "does not match" "" { target c++17_down } .-1 } +}; + +struct M3 { + M3(const volatile M3&&) = default; // { dg-warning "implicitly deleted" "" { target c++20 } } + // { dg-error "does not match" "" { target c++17_down } .-1 } +}; diff --git a/gcc/testsuite/g++.dg/cpp0x/defaulted64.C b/gcc/testsuite/g++.dg/cpp0x/defaulted64.C new file mode 100644 index 00000000000..f20030192c3 --- /dev/null +++ b/gcc/testsuite/g++.dg/cpp0x/defaulted64.C @@ -0,0 +1,27 @@ +// PR c++/116162 +// { dg-do compile { target c++11 } } + +struct M +{ + M& operator=(M&&); +}; + +struct R +{ + R& operator=(R&&) = default; + M m; +}; + +struct S +{ + S& operator=(const S&&) = default; // { dg-warning "implicitly deleted" "" { target c++20 } } + // { dg-error "does not match" "" { target c++17_down } .-1 } + + M m; +}; + +struct T +{ + T operator=(T&&) = default; // { dg-error "defaulted" } + M m; +}; diff --git a/gcc/testsuite/g++.dg/cpp0x/defaulted65.C b/gcc/testsuite/g++.dg/cpp0x/defaulted65.C new file mode 100644 index 00000000000..88ca1d96084 --- /dev/null +++ b/gcc/testsuite/g++.dg/cpp0x/defaulted65.C @@ -0,0 +1,25 @@ +// PR c++/116162 +// { dg-do compile { target c++11 } } + +struct S +{ + S& operator=(S &&) = default; +}; + +struct T +{ + T& operator=(volatile T &&) = default; // { dg-error "defaulted" "" { target c++17_down } } + // { dg-warning "implicitly deleted" "" { target c++20 } .-1 } +}; + +struct U +{ + U& operator=(const volatile U &&) = default; // { dg-error "defaulted" "" { target c++17_down } } + // { dg-warning "implicitly deleted" "" { target c++20 } .-1 } +}; + +struct V +{ + V& operator=(const V &&) = default; // { dg-error "defaulted" "" { target c++17_down } } + // { dg-warning "implicitly deleted" "" { target c++20 } .-1 } +}; diff --git a/gcc/testsuite/g++.dg/cpp0x/defaulted66.C b/gcc/testsuite/g++.dg/cpp0x/defaulted66.C new file mode 100644 index 00000000000..00d3e43e89f --- /dev/null +++ b/gcc/testsuite/g++.dg/cpp0x/defaulted66.C @@ -0,0 +1,35 @@ +// PR c++/116162 +// { dg-do compile { target c++11 } } +// Check that there is no -Wdefaulted-function-deleted for template +// instantiations. + +template +struct C { + C(); + C(const C&&) = default; // { dg-error "implicitly deleted" "" { target c++17_down} } +}; + +struct D { + D(const D&&) = default; // { dg-error "implicitly deleted" "" { target c++17_down} } + // { dg-warning "implicitly deleted" "" { target c++20 } .-1 } +}; + +struct M { + M(); + // So that W wouldn't have had "const W&" copy ctor if it were + // implicitly declared. + M(M&); +}; + +struct W { + W(); + W(const W&) = default; // { dg-error "implicitly deleted" "" { target c++17_down} } + // { dg-warning "implicitly deleted" "" { target c++20 } .-1 } + M m; +}; + +void +g () +{ + C c; +} diff --git a/gcc/testsuite/g++.dg/cpp23/defaulted1.C b/gcc/testsuite/g++.dg/cpp23/defaulted1.C new file mode 100644 index 00000000000..00cf894fa1d --- /dev/null +++ b/gcc/testsuite/g++.dg/cpp23/defaulted1.C @@ -0,0 +1,23 @@ +// PR c++/116162 +// { dg-do compile { target c++23 } } + +struct M +{ + M& operator=(M&); +}; + +struct T +{ + // if F1 is an assignment operator, and the return type of F1 differs + // from the return type, the program is ill-formed. + T operator=(this T&, T&) = default; // { dg-error "defaulted" } + M m; +}; + +struct U +{ + // if F1's non-object parameter type is not a reference, the program + // is ill-formed. + U& operator=(this U&, U) = default; // { dg-error "defaulted" } + M m; +};