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[130.44.159.43]) by smtp.gmail.com with ESMTPSA id g1sm10614204qkd.89.2021.10.05.20.01.39 (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Tue, 05 Oct 2021 20:01:39 -0700 (PDT) Message-ID: Date: Tue, 5 Oct 2021 23:01:38 -0400 MIME-Version: 1.0 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:91.0) Gecko/20100101 Thunderbird/91.1.2 Subject: Re: [PATCH, v2] c++: Implement C++23 P2242R3 - Non-literal variables (and labels and gotos) in constexpr functions To: Jakub Jelinek Cc: gcc-patches@gcc.gnu.org References: <20211005123910.GW304296@tucnak> <10d91c01-590c-1c38-6503-9acbf72d241c@redhat.com> <20211005222456.GC304296@tucnak> From: Jason Merrill In-Reply-To: <20211005222456.GC304296@tucnak> X-Mimecast-Spam-Score: 0 X-Mimecast-Originator: redhat.com Content-Language: en-US Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit X-Spam-Status: No, score=-6.8 required=5.0 tests=BAYES_00, DKIMWL_WL_HIGH, DKIM_SIGNED, DKIM_VALID, DKIM_VALID_AU, DKIM_VALID_EF, NICE_REPLY_A, RCVD_IN_DNSWL_LOW, RCVD_IN_MSPIKE_H2, SPF_HELO_NONE, SPF_NONE, TXREP autolearn=ham autolearn_force=no version=3.4.4 X-Spam-Checker-Version: SpamAssassin 3.4.4 (2020-01-24) 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-List-Received-Date: Wed, 06 Oct 2021 03:01:47 -0000 On 10/5/21 18:24, Jakub Jelinek wrote: > On Tue, Oct 05, 2021 at 05:24:09PM -0400, Jason Merrill wrote: >> That seems correct to me. If they have static initialization, they are >> initialized. > > Ok, I've included those tests in the patch now too. >>> @@ -8736,14 +8765,14 @@ potential_constant_expression_1 (tree t, >>> tmp = DECL_EXPR_DECL (t); >>> if (VAR_P (tmp) && !DECL_ARTIFICIAL (tmp)) >>> { >>> - if (TREE_STATIC (tmp)) >>> + if (TREE_STATIC (tmp) && cxx_dialect < cxx23) >>> { >>> if (flags & tf_error) >>> error_at (DECL_SOURCE_LOCATION (tmp), "%qD declared " >>> "% in % context", tmp); >>> return false; >>> } >>> - else if (CP_DECL_THREAD_LOCAL_P (tmp)) >>> + else if (CP_DECL_THREAD_LOCAL_P (tmp) && cxx_dialect < cxx23) >>> { >>> if (flags & tf_error) >>> error_at (DECL_SOURCE_LOCATION (tmp), "%qD declared " >> >> Hmm, I wouldn't expect this hunk to be needed; if there's a control path >> that doesn't include these declarations, we shouldn't hit these errors. > > You're right, that is unnecessary, if the static/thread_local declaration > is unconditional, we can (but aren't required to) diagnose it even when > the constexpr function is never evaluated in constant expressions. > But, I had to swap the TREE_STATIC and CP_DECL_THREAD_LOCAL_P checks > because the latter implies the former and so static would be always > printed instead of thread_local for thread_local declarations. > >>> @@ -9025,7 +9054,7 @@ potential_constant_expression_1 (tree t, >>> case LABEL_EXPR: >>> t = LABEL_EXPR_LABEL (t); >>> - if (DECL_ARTIFICIAL (t)) >>> + if (DECL_ARTIFICIAL (t) || cxx_dialect >= cxx23) >>> return true; >>> else if (flags & tf_error) >>> error_at (loc, "label definition is not a constant expression"); >> >> Let's change this message to "only available with..." like the others. > > Changed too. > > Here is an updated patch (also after IRC chat with Jonathan changed > the __cpp_constexpr value from 202103L that was in the paper to 202110L). > Passes the tests that are modified so far, full bootstrap/regtest > queued after my current one finishes. OK. > 2021-10-06 Jakub Jelinek > > gcc/c-family/ > * c-cppbuiltin.c (c_cpp_builtins): For -std=c++23 predefine > __cpp_constexpr to 202110L rather than 201907L. > gcc/cp/ > * parser.c (cp_parser_jump_statement): Implement C++23 P2242R3. > Allow goto expressions in constexpr function bodies for C++23. > Adjust error message for older standards to mention it. > * decl.c (start_decl): Allow static and thread_local declarations > in constexpr function bodies for C++23. Adjust error message for > older standards to mention it. > * constexpr.c (ensure_literal_type_for_constexpr_object): Allow > declarations of variables with non-literal type in constexpr function > bodies for C++23. Adjust error message for older standards to mention > it. > (cxx_eval_constant_expression) : Diagnose declarations > of initialization of static or thread_local vars. > (cxx_eval_constant_expression) : Diagnose goto > statements for C++23. > (potential_constant_expression_1) : Swap the > CP_DECL_THREAD_LOCAL_P and TREE_STATIC checks. > (potential_constant_expression_1) : Allow labels for > C++23. Adjust error message for older standards to mention it. > gcc/testsuite/ > * g++.dg/cpp23/feat-cxx2b.C: Expect __cpp_constexpr 202110L rather > than 201907L. > * g++.dg/cpp23/constexpr-nonlit1.C: New test. > * g++.dg/cpp23/constexpr-nonlit2.C: New test. > * g++.dg/cpp23/constexpr-nonlit3.C: New test. > * g++.dg/cpp23/constexpr-nonlit4.C: New test. > * g++.dg/cpp23/constexpr-nonlit5.C: New test. > * g++.dg/cpp23/constexpr-nonlit6.C: New test. > * g++.dg/diagnostic/constexpr1.C: Only expect some diagnostics for > c++20_down. > * g++.dg/cpp1y/constexpr-label.C: Likewise. > * g++.dg/cpp1y/constexpr-neg1.C: Likewise. > * g++.dg/cpp2a/constexpr-try5.C: Likewise. Adjust some expected > wording. > * g++.dg/cpp2a/constexpr-dtor3.C: Likewise. > * g++.dg/cpp2a/consteval3.C: Likewise. Add effective target c++20 > and remove dg-options. > > --- gcc/c-family/c-cppbuiltin.c.jj 2021-10-05 22:27:39.387959561 +0200 > +++ gcc/c-family/c-cppbuiltin.c 2021-10-05 23:47:13.865054265 +0200 > @@ -1052,7 +1052,8 @@ c_cpp_builtins (cpp_reader *pfile) > cpp_define (pfile, "__cpp_init_captures=201803L"); > cpp_define (pfile, "__cpp_generic_lambdas=201707L"); > cpp_define (pfile, "__cpp_designated_initializers=201707L"); > - cpp_define (pfile, "__cpp_constexpr=201907L"); > + if (cxx_dialect <= cxx20) > + cpp_define (pfile, "__cpp_constexpr=201907L"); > cpp_define (pfile, "__cpp_constexpr_in_decltype=201711L"); > cpp_define (pfile, "__cpp_conditional_explicit=201806L"); > cpp_define (pfile, "__cpp_consteval=201811L"); > @@ -1071,6 +1072,7 @@ c_cpp_builtins (cpp_reader *pfile) > /* Set feature test macros for C++23. */ > cpp_define (pfile, "__cpp_size_t_suffix=202011L"); > cpp_define (pfile, "__cpp_if_consteval=202106L"); > + cpp_define (pfile, "__cpp_constexpr=202110L"); > } > if (flag_concepts) > { > --- gcc/cp/parser.c.jj 2021-10-05 22:27:39.551957300 +0200 > +++ gcc/cp/parser.c 2021-10-05 23:47:13.895053851 +0200 > @@ -14176,9 +14176,11 @@ cp_parser_jump_statement (cp_parser* par > > case RID_GOTO: > if (parser->in_function_body > - && DECL_DECLARED_CONSTEXPR_P (current_function_decl)) > + && DECL_DECLARED_CONSTEXPR_P (current_function_decl) > + && cxx_dialect < cxx23) > { > - error ("% in % function"); > + error ("% in % function only available with " > + "%<-std=c++2b%> or %<-std=gnu++2b%>"); > cp_function_chain->invalid_constexpr = true; > } > > --- gcc/cp/decl.c.jj 2021-10-05 22:27:39.502957976 +0200 > +++ gcc/cp/decl.c 2021-10-05 23:47:13.916053561 +0200 > @@ -5709,17 +5709,20 @@ start_decl (const cp_declarator *declara > } > > if (current_function_decl && VAR_P (decl) > - && DECL_DECLARED_CONSTEXPR_P (current_function_decl)) > + && DECL_DECLARED_CONSTEXPR_P (current_function_decl) > + && cxx_dialect < cxx23) > { > bool ok = false; > if (CP_DECL_THREAD_LOCAL_P (decl)) > error_at (DECL_SOURCE_LOCATION (decl), > - "%qD declared % in %qs function", decl, > + "%qD declared % in %qs function only " > + "available with %<-std=c++2b%> or %<-std=gnu++2b%>", decl, > DECL_IMMEDIATE_FUNCTION_P (current_function_decl) > ? "consteval" : "constexpr"); > else if (TREE_STATIC (decl)) > error_at (DECL_SOURCE_LOCATION (decl), > - "%qD declared % in %qs function", decl, > + "%qD declared % in %qs function only available " > + "with %<-std=c++2b%> or %<-std=gnu++2b%>", decl, > DECL_IMMEDIATE_FUNCTION_P (current_function_decl) > ? "consteval" : "constexpr"); > else > --- gcc/cp/constexpr.c.jj 2021-10-05 22:27:48.009840663 +0200 > +++ gcc/cp/constexpr.c 2021-10-06 00:08:16.809608246 +0200 > @@ -109,14 +109,15 @@ ensure_literal_type_for_constexpr_object > explain_non_literal_class (type); > decl = error_mark_node; > } > - else > + else if (cxx_dialect < cxx23) > { > if (!is_instantiation_of_constexpr (current_function_decl)) > { > auto_diagnostic_group d; > error_at (DECL_SOURCE_LOCATION (decl), > "variable %qD of non-literal type %qT in " > - "% function", decl, type); > + "% function only available with " > + "%<-std=c++2b%> or %<-std=gnu++2b%>", decl, type); > explain_non_literal_class (type); > decl = error_mark_node; > } > @@ -6345,6 +6346,26 @@ cxx_eval_constant_expression (const cons > r = void_node; > break; > } > + > + if (VAR_P (r) > + && (TREE_STATIC (r) || CP_DECL_THREAD_LOCAL_P (r)) > + /* Allow __FUNCTION__ etc. */ > + && !DECL_ARTIFICIAL (r)) > + { > + gcc_assert (cxx_dialect >= cxx23); > + if (!ctx->quiet) > + { > + if (CP_DECL_THREAD_LOCAL_P (r)) > + error_at (loc, "control passes through declaration of %qD " > + "with thread storage duration", r); > + else > + error_at (loc, "control passes through declaration of %qD " > + "with static storage duration", r); > + } > + *non_constant_p = true; > + break; > + } > + > if (AGGREGATE_TYPE_P (TREE_TYPE (r)) > || VECTOR_TYPE_P (TREE_TYPE (r))) > { > @@ -7049,10 +7070,18 @@ cxx_eval_constant_expression (const cons > break; > > case GOTO_EXPR: > - *jump_target = TREE_OPERAND (t, 0); > - gcc_assert (breaks (jump_target) || continues (jump_target) > - /* Allow for jumping to a cdtor_label. */ > - || returns (jump_target)); > + if (breaks (&TREE_OPERAND (t, 0)) > + || continues (&TREE_OPERAND (t, 0)) > + /* Allow for jumping to a cdtor_label. */ > + || returns (&TREE_OPERAND (t, 0))) > + *jump_target = TREE_OPERAND (t, 0); > + else > + { > + gcc_assert (cxx_dialect >= cxx23); > + if (!ctx->quiet) > + error_at (loc, "% is not a constant expression"); > + *non_constant_p = true; > + } > break; > > case LOOP_EXPR: > @@ -8736,18 +8765,18 @@ potential_constant_expression_1 (tree t, > tmp = DECL_EXPR_DECL (t); > if (VAR_P (tmp) && !DECL_ARTIFICIAL (tmp)) > { > - if (TREE_STATIC (tmp)) > + if (CP_DECL_THREAD_LOCAL_P (tmp)) > { > if (flags & tf_error) > error_at (DECL_SOURCE_LOCATION (tmp), "%qD declared " > - "% in % context", tmp); > + "% in % context", tmp); > return false; > } > - else if (CP_DECL_THREAD_LOCAL_P (tmp)) > + else if (TREE_STATIC (tmp)) > { > if (flags & tf_error) > error_at (DECL_SOURCE_LOCATION (tmp), "%qD declared " > - "% in % context", tmp); > + "% in % context", tmp); > return false; > } > else if (!check_for_uninitialized_const_var > @@ -9025,10 +9054,11 @@ potential_constant_expression_1 (tree t, > > case LABEL_EXPR: > t = LABEL_EXPR_LABEL (t); > - if (DECL_ARTIFICIAL (t)) > + if (DECL_ARTIFICIAL (t) || cxx_dialect >= cxx23) > return true; > else if (flags & tf_error) > - error_at (loc, "label definition is not a constant expression"); > + error_at (loc, "label definition in % function only " > + "available with %<-std=c++2b%> or %<-std=gnu++2b%>"); > return false; > > case ANNOTATE_EXPR: > --- gcc/testsuite/g++.dg/cpp23/feat-cxx2b.C.jj 2021-10-05 22:27:39.594956707 +0200 > +++ gcc/testsuite/g++.dg/cpp23/feat-cxx2b.C 2021-10-06 00:02:37.480296129 +0200 > @@ -134,8 +134,8 @@ > > #ifndef __cpp_constexpr > # error "__cpp_constexpr" > -#elif __cpp_constexpr != 201907 > -# error "__cpp_constexpr != 201907" > +#elif __cpp_constexpr != 202110 > +# error "__cpp_constexpr != 202110" > #endif > > #ifndef __cpp_decltype_auto > --- gcc/testsuite/g++.dg/cpp23/constexpr-nonlit1.C.jj 2021-10-05 23:47:13.934053312 +0200 > +++ gcc/testsuite/g++.dg/cpp23/constexpr-nonlit1.C 2021-10-05 23:52:09.879965662 +0200 > @@ -0,0 +1,68 @@ > +// P2242R3 > +// { dg-do compile { target c++14 } } > + > +constexpr int > +foo () > +{ > +lab: // { dg-error "label definition in 'constexpr' function only available with" "" { target c++20_down } } > + return 1; > +} > + > +constexpr int > +bar (int x) > +{ > + if (x) > + goto lab; // { dg-error "'goto' in 'constexpr' function only available with" "" { target c++20_down } } > + return 1; > +lab: > + return 0; > +} > + > +constexpr int > +baz (int x) > +{ > + if (!x) > + return 1; > + static int a; // { dg-error "'a' declared 'static' in 'constexpr' function only available with" "" { target c++20_down } } > + return ++a; // { dg-error "uninitialized variable 'a' in 'constexpr' function" "" { target c++17_down } .-1 } > +} > + > +constexpr int > +qux (int x) > +{ > + if (!x) > + return 1; > + thread_local int a; // { dg-error "'a' declared 'thread_local' in 'constexpr' function only available with" "" { target c++20_down } } > + return ++a; // { dg-error "uninitialized variable 'a' in 'constexpr' function" "" { target c++17_down } .-1 } > +} > + > +constexpr int > +garply (int x) > +{ > + if (!x) > + return 1; > + extern thread_local int a; // { dg-error "'a' declared 'thread_local' in 'constexpr' function only available with" "" { target c++20_down } } > + return ++a; > +} > + > +struct S { S (); ~S (); int s; }; // { dg-message "'S' is not literal because:" "" { target c++20_down } } > + // { dg-message "'S' has a non-trivial destructor" "" { target c++17_down } .-1 } > + // { dg-message "'S' does not have 'constexpr' destructor" "" { target { c++20_only } } .-2 } > + > +constexpr int > +corge (int x) > +{ > + if (!x) > + return 1; > + S s; // { dg-error "variable 's' of non-literal type 'S' in 'constexpr' function only available with" "" { target c++20_down } } > + return 0; > +} > + > +#if __cpp_constexpr >= 202110L > +static_assert (foo ()); > +static_assert (bar (0)); > +static_assert (baz (0)); > +static_assert (qux (0)); > +static_assert (garply (0)); > +static_assert (corge (0)); > +#endif > --- gcc/testsuite/g++.dg/cpp23/constexpr-nonlit2.C.jj 2021-10-05 23:47:13.934053312 +0200 > +++ gcc/testsuite/g++.dg/cpp23/constexpr-nonlit2.C 2021-10-06 00:14:12.586693301 +0200 > @@ -0,0 +1,54 @@ > +// P2242R3 > +// { dg-do compile } > +// { dg-options "-std=c++2b" } > + > +constexpr int > +foo () > +{ > +lab: > + return 1; > +} > + > +constexpr int > +bar (int x) > +{ > + if (x) > + goto lab; // { dg-error "'goto' is not a constant expression" } > + return 1; > +lab: > + return 0; > +} > + > +constexpr int > +baz (int x) > +{ > + if (!x) > + return 1; > + static int a; // { dg-error "control passes through declaration of 'a' with static storage duration" } > + return ++a; > +} > + > +constexpr int > +qux (int x) > +{ > + if (!x) > + return 1; > + thread_local int a; // { dg-error "control passes through declaration of 'a' with thread storage duration" } > + return ++a; > +} > + > +struct S { S (); ~S (); int s; }; // { dg-message "'S::S\\\(\\\)' declared here" } > + > +constexpr int > +corge (int x) > +{ > + if (!x) > + return 1; > + S s; // { dg-error "call to non-'constexpr' function 'S::S\\\(\\\)'" } > + return 0; > +} > + > +constexpr int a = bar (1); // { dg-message "in 'constexpr' expansion of" } > +constexpr int b = baz (1); // { dg-message "in 'constexpr' expansion of" } > +constexpr int c = qux (1); // { dg-message "in 'constexpr' expansion of" } > +constexpr int d = corge (1); // { dg-message "in 'constexpr' expansion of" } > --- gcc/testsuite/g++.dg/cpp23/constexpr-nonlit3.C.jj 2021-10-05 23:47:13.934053312 +0200 > +++ gcc/testsuite/g++.dg/cpp23/constexpr-nonlit3.C 2021-10-05 23:47:13.934053312 +0200 > @@ -0,0 +1,10 @@ > +// P2242R3 > +// { dg-do compile { target c++14 } } > + > +constexpr int > +foo () > +{ > + goto lab; // { dg-error "'goto' in 'constexpr' function only available with" "" { target c++20_down } } > +lab: // { dg-error "'goto' is not a constant expression" "" { target { c++23 } } .-1 } > + return 1; > +} > --- gcc/testsuite/g++.dg/cpp23/constexpr-nonlit4.C.jj 2021-10-05 23:58:42.437543278 +0200 > +++ gcc/testsuite/g++.dg/cpp23/constexpr-nonlit4.C 2021-10-05 23:55:57.699818980 +0200 > @@ -0,0 +1,57 @@ > +// { dg-do compile } > +// { dg-options "-std=c++2b" } > + > +int qux (); > + > +constexpr int > +foo (int x) > +{ > + switch (x) > + { > + static int v = qux (); > + case 12: > + return 1; > + } > + return 0; > +} > + > +constexpr int > +bar (int x) > +{ > + switch (x) > + { > + thread_local int v = qux (); > + case 12: > + return 1; > + } > + return 0; > +} > + > +constexpr int > +baz (int x) > +{ > + switch (x) > + { > + static const int v = qux (); // { dg-message "'v' was not initialized with a constant expression" } > + case 12: > + return v; > + } > + return 0; > +} > + > +constexpr int > +corge (int x) > +{ > + switch (x) > + { > + const thread_local int v = qux (); // { dg-message "'v' was not initialized with a constant expression" } > + case 12: > + return v; > + } > + return 0; > +} > + > +constexpr int a = foo (12); > +constexpr int b = bar (12); > +constexpr int c = baz (12); // { dg-error "the value of 'v' is not usable in a constant expression" } > +constexpr int d = corge (12); // { dg-error "the value of 'v' is not usable in a constant expression" } > --- gcc/testsuite/g++.dg/cpp23/constexpr-nonlit5.C.jj 2021-10-05 23:58:47.250476787 +0200 > +++ gcc/testsuite/g++.dg/cpp23/constexpr-nonlit5.C 2021-10-05 23:58:12.130961967 +0200 > @@ -0,0 +1,57 @@ > +// { dg-do compile } > +// { dg-options "-std=c++2b" } > + > +int qux (); > + > +constexpr int > +foo (int x) > +{ > + switch (x) > + { > + static const int v = 6; > + case 12: > + return v; > + } > + return 0; > +} > + > +constexpr int > +bar (int x) > +{ > + switch (x) > + { > + thread_local const int v = 7; > + case 12: > + return 7; > + } > + return 0; > +} > + > +constexpr int > +baz (int x) > +{ > + switch (x) > + { > + static int v = 6; // { dg-message "int v' is not const" } > + case 12: > + return v; > + } > + return 0; > +} > + > +constexpr int > +corge (int x) > +{ > + switch (x) > + { > + thread_local int v = 6; // { dg-message "int v' is not const" } > + case 12: > + return v; > + } > + return 0; > +} > + > +constexpr int a = foo (12); > +constexpr int b = bar (12); > +constexpr int c = baz (12); // { dg-error "the value of 'v' is not usable in a constant expression" } > +constexpr int d = corge (12); // { dg-error "the value of 'v' is not usable in a constant expression" } > --- gcc/testsuite/g++.dg/cpp23/constexpr-nonlit6.C.jj 2021-10-06 00:12:19.927249541 +0200 > +++ gcc/testsuite/g++.dg/cpp23/constexpr-nonlit6.C 2021-10-06 00:15:32.680587909 +0200 > @@ -0,0 +1,25 @@ > +// P2242R3 > +// { dg-do compile } > +// { dg-options "-std=c++2b" } > + > +constexpr int > +foo () > +{ > + goto lab; // { dg-error "'goto' is not a constant expression" } > +lab: > + return 1; > +} > + > +constexpr int > +bar () > +{ > + static int a; // { dg-error "'a' declared 'static' in 'constexpr' context" } > + return ++a; > +} > + > +constexpr int > +baz (int x) > +{ > + thread_local int a; // { dg-error "'a' declared 'thread_local' in 'constexpr' context" } > + return ++a; > +} > --- gcc/testsuite/g++.dg/diagnostic/constexpr1.C.jj 2020-01-12 11:54:37.155402214 +0100 > +++ gcc/testsuite/g++.dg/diagnostic/constexpr1.C 2021-10-06 00:08:47.990177482 +0200 > @@ -1,5 +1,7 @@ > // { dg-do compile { target c++11 } } > > -constexpr int foo() { thread_local int i __attribute__((unused)) {}; return 1; } // { dg-error "40:.i. declared .thread_local." } > +constexpr int foo() { thread_local int i __attribute__((unused)) {}; return 1; } // { dg-error "40:.i. declared .thread_local." "" { target c++20_down } } > +// { dg-error "40:.i. declared .thread_local. in .constexpr. context" "" { target c++23 } .-1 } > > -constexpr int bar() { static int i __attribute__((unused)) {}; return 1; } // { dg-error "34:.i. declared .static." } > +constexpr int bar() { static int i __attribute__((unused)) {}; return 1; } // { dg-error "34:.i. declared .static." "" { target c++20_down } } > +// { dg-error "34:.i. declared .static. in .constexpr. context" "" { target c++23 } .-1 } > --- gcc/testsuite/g++.dg/cpp1y/constexpr-label.C.jj 2020-11-22 19:11:44.103588521 +0100 > +++ gcc/testsuite/g++.dg/cpp1y/constexpr-label.C 2021-10-05 23:52:09.879965662 +0200 > @@ -4,6 +4,6 @@ > constexpr int > f () > { > -x: // { dg-error "label definition is not a constant expression" } > +x: // { dg-error "label definition in 'constexpr' function only available with" "" { target c++20_down } } > return 42; > } > --- gcc/testsuite/g++.dg/cpp1y/constexpr-neg1.C.jj 2020-01-12 11:54:37.115402818 +0100 > +++ gcc/testsuite/g++.dg/cpp1y/constexpr-neg1.C 2021-10-06 00:01:48.736969524 +0200 > @@ -4,12 +4,12 @@ struct A { A(); }; > > constexpr int f(int i) { > static int j = i; // { dg-error "static" } > - thread_local int l = i; // { dg-error "thread_local" } > - goto foo; // { dg-error "goto" } > + thread_local int l = i; // { dg-error "thread_local" "" { target c++20_down } } > + goto foo; // { dg-error "goto" "" { target c++20_down } } > foo: > asm("foo"); // { dg-error "asm" "" { target c++17_down } } > int k; // { dg-error "uninitialized" "" { target c++17_down } } > - A a; // { dg-error "non-literal" } > + A a; // { dg-error "non-literal" "" { target c++20_down } } > return i; > } > > --- gcc/testsuite/g++.dg/cpp2a/constexpr-try5.C.jj 2020-01-12 11:54:37.141402425 +0100 > +++ gcc/testsuite/g++.dg/cpp2a/constexpr-try5.C 2021-10-06 00:11:41.897774924 +0200 > @@ -5,14 +5,15 @@ > constexpr int foo () > try { // { dg-warning "function-try-block body of 'constexpr' function only available with" "" { target c++17_down } } > int a; // { dg-error "uninitialized variable 'a' in 'constexpr' function" "" { target c++17_down } } > - static double b = 1.0;// { dg-error "'b' declared 'static' in 'constexpr' function" } > - goto l; // { dg-error "'goto' in 'constexpr' function" } > + static double b = 1.0;// { dg-error "'b' declared 'static' in 'constexpr' function only available with" "" { target c++20_down } } > + // { dg-error "'b' declared 'static' in 'constexpr' context" "" { target c++23 } .-1 } > + goto l; // { dg-error "'goto' in 'constexpr' function only available with" "" { target c++20_down } } > l:; > return 0; > } catch (...) { > long int c; // { dg-error "uninitialized variable 'c' in 'constexpr' function" "" { target c++17_down } } > - static float d = 2.0f;// { dg-error "'d' declared 'static' in 'constexpr' function" } > - goto l2; // { dg-error "'goto' in 'constexpr' function" } > + static float d = 2.0f;// { dg-error "'d' declared 'static' in 'constexpr' function only available with" "" { target c++20_down } } > + goto l2; // { dg-error "'goto' in 'constexpr' function only available with" "" { target c++20_down } } > l2:; > return -1; > } > @@ -20,20 +21,21 @@ try { // { dg-warning "function-try-bl > constexpr int bar () > { > int a; // { dg-error "uninitialized variable 'a' in 'constexpr' function" "" { target c++17_down } } > - static long double b = 3.0;// { dg-error "'b' declared 'static' in 'constexpr' function" } > - goto l; // { dg-error "'goto' in 'constexpr' function" } > + static long double b = 3.0;// { dg-error "'b' declared 'static' in 'constexpr' function only available with" "" { target c++20_down } } > + // { dg-error "'b' declared 'static' in 'constexpr' context" "" { target c++23 } .-1 } > + goto l; // { dg-error "'goto' in 'constexpr' function only available with" "" { target c++20_down } } > l:; > try { // { dg-warning "'try' in 'constexpr' function only available with" "" { target c++17_down } } > short c; // { dg-error "uninitialized variable 'c' in 'constexpr' function" "" { target c++17_down } } > - static float d; // { dg-error "'d' declared 'static' in 'constexpr' function" } > + static float d; // { dg-error "'d' declared 'static' in 'constexpr' function only available with" "" { target c++20_down } } > // { dg-error "uninitialized variable 'd' in 'constexpr' function" "" { target c++17_down } .-1 } > - goto l2; // { dg-error "'goto' in 'constexpr' function" } > + goto l2; // { dg-error "'goto' in 'constexpr' function only available with" "" { target c++20_down } } > l2:; > return 0; > } catch (int) { > char e; // { dg-error "uninitialized variable 'e' in 'constexpr' function" "" { target c++17_down } } > - static int f = 5; // { dg-error "'f' declared 'static' in 'constexpr' function" } > - goto l3; // { dg-error "'goto' in 'constexpr' function" } > + static int f = 5; // { dg-error "'f' declared 'static' in 'constexpr' function only available with" "" { target c++20_down } } > + goto l3; // { dg-error "'goto' in 'constexpr' function only available with" "" { target c++20_down } } > l3:; > return 1; > } > --- gcc/testsuite/g++.dg/cpp2a/constexpr-dtor3.C.jj 2021-04-14 10:48:41.330103579 +0200 > +++ gcc/testsuite/g++.dg/cpp2a/constexpr-dtor3.C 2021-10-05 23:47:13.970052815 +0200 > @@ -180,6 +180,6 @@ f7 () > constexpr int > f8 () > { > - T t4; // { dg-error "variable 't4' of non-literal type 'T' in 'constexpr' function" } > + T t4; // { dg-error "variable 't4' of non-literal type 'T' in 'constexpr' function only available with" "" { target c++20_down } } > return 0; > } > --- gcc/testsuite/g++.dg/cpp2a/consteval3.C.jj 2020-02-28 17:34:56.393567559 +0100 > +++ gcc/testsuite/g++.dg/cpp2a/consteval3.C 2021-10-06 00:10:50.161489668 +0200 > @@ -1,5 +1,4 @@ > -// { dg-do compile } > -// { dg-options "-std=c++2a" } > +// { dg-do compile { target c++20 } } > > struct S { S () : a (0), b (1) {} int a, b; }; > int f1 (); // { dg-message "previous declaration 'int f1\\(\\)'" } > @@ -57,7 +56,8 @@ template consteval float f12 (float x); > consteval int > f13 (int x) > { > - static int a = 5; // { dg-error "'a' declared 'static' in 'consteval' function" } > - thread_local int b = 6; // { dg-error "'b' declared 'thread_local' in 'consteval' function" } > + static int a = 5; // { dg-error "'a' declared 'static' in 'consteval' function only available with" "" { target c++20_only } } > + // { dg-error "'a' declared 'static' in 'constexpr' context" "" { target c++23 } .-1 } > + thread_local int b = 6; // { dg-error "'b' declared 'thread_local' in 'consteval' function only available with" "" { target c++20_only } } > return x; > } > > Jakub >