From: Jonathan Wakely Date: Fri, 7 Oct 2022 11:18:57 +0000 (+0100) Subject: libstdc++: std::make_signed_t should be ill-formed X-Git-Tag: basepoints/gcc-14~4015 X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=2bd112dee7f9786a0484d9281899a9bb0b2ae57d;p=thirdparty%2Fgcc.git libstdc++: std::make_signed_t should be ill-formed Currently we only reject std::make_signed_t but not cv bool. Similarly for std::make_unsigned_t. As well as making those ill-formed, this adds a requires-clause to the make_signed and make_unsigned primary templates. This makes non-integral, non-enum cases fail immediately with a clear error, rather than giving an error about __make_signed_selector being incomplete. libstdc++-v3/ChangeLog: * include/std/type_traits (make_signed, make_unsigned): Add specializations for cv bool. Add requires-clause for C++20 to improve diagnostics for non-integral, non-enum cases. * testsuite/20_util/make_signed/requirements/typedefs_neg.cc: Check cv bool. * testsuite/20_util/make_unsigned/requirements/typedefs_neg.cc: Likewise. * testsuite/24_iterators/range_access/range_access_cpp20_neg.cc: Adjust expected errors for C++20 and later. * testsuite/lib/prune.exp: Prune "in requirements [with ...]" lines from diagnostics. --- diff --git a/libstdc++-v3/include/std/type_traits b/libstdc++-v3/include/std/type_traits index b74565eb521e..6108b98aa6a6 100644 --- a/libstdc++-v3/include/std/type_traits +++ b/libstdc++-v3/include/std/type_traits @@ -1802,12 +1802,17 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION // Primary template. /// make_unsigned template +#if __cpp_concepts + requires is_integral<_Tp>::value || __is_enum(_Tp) +#endif struct make_unsigned { typedef typename __make_unsigned_selector<_Tp>::__type type; }; // Integral, but don't define. - template<> - struct make_unsigned; + template<> struct make_unsigned; + template<> struct make_unsigned; + template<> struct make_unsigned; + template<> struct make_unsigned; /// @cond undocumented @@ -1932,12 +1937,17 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION // Primary template. /// make_signed template +#if __cpp_concepts + requires is_integral<_Tp>::value || __is_enum(_Tp) +#endif struct make_signed { typedef typename __make_signed_selector<_Tp>::__type type; }; // Integral, but don't define. - template<> - struct make_signed; + template<> struct make_signed; + template<> struct make_signed; + template<> struct make_signed; + template<> struct make_signed; #if __cplusplus > 201103L /// Alias template for make_signed diff --git a/libstdc++-v3/testsuite/20_util/make_signed/requirements/typedefs_neg.cc b/libstdc++-v3/testsuite/20_util/make_signed/requirements/typedefs_neg.cc index 051bb64c710c..88b8ae887ef4 100644 --- a/libstdc++-v3/testsuite/20_util/make_signed/requirements/typedefs_neg.cc +++ b/libstdc++-v3/testsuite/20_util/make_signed/requirements/typedefs_neg.cc @@ -20,31 +20,28 @@ // . #include -#include -enum test_enum { first_selection }; +struct pod_class { }; void test01() { using std::make_signed; // Negative tests. - typedef make_signed::type test1_type; + using T1 = make_signed::type; // { dg-error "incomplete" } + using T2 = make_signed::type; // { dg-error "incomplete" } + using T3 = make_signed::type; // { dg-error "incomplete" } + using T4 = make_signed::type; // { dg-error "incomplete" } - typedef make_signed<__gnu_test::pod_uint>::type test2_type; + using T5 = make_signed::type; // { dg-error "here" } - typedef make_signed::type test3_type; + using T6 = make_signed::type; // { dg-error "here" } - typedef void (fn_type) (); - typedef make_signed::type test4_type; + using fn_type = void (); + using T7 = make_signed::type; // { dg-error "here" } - typedef make_signed::type test5_type; + using T8 = make_signed::type; // { dg-error "here" } } -// { dg-error "invalid use of incomplete type" "" { target *-*-* } 32 } -// { dg-error "required from here" "" { target *-*-* } 34 } -// { dg-error "required from here" "" { target *-*-* } 36 } -// { dg-error "required from here" "" { target *-*-* } 39 } -// { dg-error "required from here" "" { target *-*-* } 41 } - -// { dg-error "invalid use of incomplete type" "" { target *-*-* } 0 } +// { dg-error "invalid use of incomplete type" "" { target c++17_down } 0 } +// { dg-error "constraint failure" "" { target c++20 } 0 } diff --git a/libstdc++-v3/testsuite/20_util/make_unsigned/requirements/typedefs_neg.cc b/libstdc++-v3/testsuite/20_util/make_unsigned/requirements/typedefs_neg.cc index ff98cc42ef7b..50f15e7037c4 100644 --- a/libstdc++-v3/testsuite/20_util/make_unsigned/requirements/typedefs_neg.cc +++ b/libstdc++-v3/testsuite/20_util/make_unsigned/requirements/typedefs_neg.cc @@ -21,7 +21,6 @@ #include -enum test_enum { first_selection }; struct pod_class { }; void test01() @@ -29,22 +28,20 @@ void test01() using std::make_unsigned; // Negative tests. - typedef make_unsigned::type test1_type; + using T1 = make_unsigned::type; // { dg-error "incomplete" } + using T2 = make_unsigned::type; // { dg-error "incomplete" } + using T3 = make_unsigned::type; // { dg-error "incomplete" } + using T4 = make_unsigned::type; // { dg-error "incomplete" } - typedef make_unsigned::type test2_type; + using T5 = make_unsigned::type; // { dg-error "here" } - typedef make_unsigned::type test3_type; + using T6 = make_unsigned::type; // { dg-error "here" } - typedef void (fn_type) (); - typedef make_unsigned::type test4_type; + using fn_type = void (); + using T7 = make_unsigned::type; // { dg-error "here" } - typedef make_unsigned::type test5_type; + using T8 = make_unsigned::type; // { dg-error "here" } } -// { dg-error "invalid use of incomplete type" "" { target *-*-* } 32 } -// { dg-error "required from here" "" { target *-*-* } 34 } -// { dg-error "required from here" "" { target *-*-* } 36 } -// { dg-error "required from here" "" { target *-*-* } 39 } -// { dg-error "required from here" "" { target *-*-* } 41 } - -// { dg-error "invalid use of incomplete type" "" { target *-*-* } 0 } +// { dg-error "invalid use of incomplete type" "" { target c++17_down } 0 } +// { dg-error "constraint failure" "" { target c++20 } 0 } diff --git a/libstdc++-v3/testsuite/24_iterators/range_access/range_access_cpp20_neg.cc b/libstdc++-v3/testsuite/24_iterators/range_access/range_access_cpp20_neg.cc index c0825a585871..26c8ae0ee1e7 100644 --- a/libstdc++-v3/testsuite/24_iterators/range_access/range_access_cpp20_neg.cc +++ b/libstdc++-v3/testsuite/24_iterators/range_access/range_access_cpp20_neg.cc @@ -46,4 +46,5 @@ test03() C c; std::ssize(c); // { dg-error "no matching function" } } -// { dg-error "incomplete type .*make_signed.*S" "" { target *-*-* } 0 } +// { dg-error "incomplete type .*make_signed.*S" "" { target c++17_down } 0 } +// { dg-error "constraint failure" "" { target c++20 } 0 } diff --git a/libstdc++-v3/testsuite/lib/prune.exp b/libstdc++-v3/testsuite/lib/prune.exp index d457e9752180..6d0b77a8ccd8 100644 --- a/libstdc++-v3/testsuite/lib/prune.exp +++ b/libstdc++-v3/testsuite/lib/prune.exp @@ -51,6 +51,7 @@ proc libstdc++-dg-prune { system text } { regsub -all "(^|\n)\[^\n\]*: (recursively )?required \[^\n\]*" $text "" text regsub -all "(^|\n)\[^\n\]*: . skipping \[0-9\]* instantiation contexts \[^\n\]*" $text "" text regsub -all "(^|\n)\[^\n\]*: in .constexpr. expansion \[^\n\]*" $text "" text + regsub -all "(^|\n)\[^\n\]*: in requirements .with\[^\n\]*" $text "" text regsub -all "(^|\n) inlined from \[^\n\]*" $text "" text # Why doesn't GCC need these to strip header context? regsub -all "(^|\n)In file included from \[^\n\]*" $text "" text