From 8df27fcb9168fe26a6bcd34f4e653e1585895354 Mon Sep 17 00:00:00 2001 From: Jonathan Wakely Date: Mon, 2 Jul 2018 23:09:25 +0100 Subject: [PATCH] P0758R1 Implicit conversion traits Extend __is_convertible_helper to also detect whether the conversion is non-throwing, for std::is_nothrow_convertible in C++2a, * include/std/type_traits [__cplusplus > 201703] (__is_convertible_helper::__is_nothrow_type): Define new member. (__is_convertible_helper<_From, _To, false>::__test_aux1): Add noexcept. (__is_convertible_helper<_From, _To, false>::__test_nothrow) (__is_convertible_helper<_From, _To, false>::__is_nothrow_type): Add new members. (is_nothrow_convertible, is_nothrow_convertible_v): Define for C++2a. * testsuite/20_util/is_nothrow_convertible/value.cc: New. * testsuite/20_util/is_nothrow_convertible/requirements/ explicit_instantiation.cc: New. * testsuite/20_util/is_nothrow_convertible/requirements/typedefs.cc: New. From-SVN: r262322 --- libstdc++-v3/ChangeLog | 15 ++ libstdc++-v3/include/std/type_traits | 38 +++- .../requirements/explicit_instantiation.cc | 29 +++ .../requirements/typedefs.cc | 33 ++++ .../20_util/is_nothrow_convertible/value.cc | 177 ++++++++++++++++++ .../make_signed/requirements/typedefs_neg.cc | 2 +- .../requirements/typedefs_neg.cc | 2 +- 7 files changed, 291 insertions(+), 5 deletions(-) create mode 100644 libstdc++-v3/testsuite/20_util/is_nothrow_convertible/requirements/explicit_instantiation.cc create mode 100644 libstdc++-v3/testsuite/20_util/is_nothrow_convertible/requirements/typedefs.cc create mode 100644 libstdc++-v3/testsuite/20_util/is_nothrow_convertible/value.cc diff --git a/libstdc++-v3/ChangeLog b/libstdc++-v3/ChangeLog index c6e84be4602..ae734e8487d 100644 --- a/libstdc++-v3/ChangeLog +++ b/libstdc++-v3/ChangeLog @@ -1,5 +1,20 @@ 2018-07-02 Jonathan Wakely + P0758R1 Implicit conversion traits + * include/std/type_traits [__cplusplus > 201703] + (__is_convertible_helper::__is_nothrow_type): Define new member. + (__is_convertible_helper<_From, _To, false>::__test_aux1): Add + noexcept. + (__is_convertible_helper<_From, _To, false>::__test_nothrow) + (__is_convertible_helper<_From, _To, false>::__is_nothrow_type): Add + new members. + (is_nothrow_convertible, is_nothrow_convertible_v): Define for C++2a. + * testsuite/20_util/is_nothrow_convertible/value.cc: New. + * testsuite/20_util/is_nothrow_convertible/requirements/ + explicit_instantiation.cc: New. + * testsuite/20_util/is_nothrow_convertible/requirements/typedefs.cc: + New. + P0887R1 The identity metafunction * include/std/type_traits (type_identity, type_identity_t): Define for C++2a. diff --git a/libstdc++-v3/include/std/type_traits b/libstdc++-v3/include/std/type_traits index b2d3380f024..accea6df648 100644 --- a/libstdc++-v3/include/std/type_traits +++ b/libstdc++-v3/include/std/type_traits @@ -1341,13 +1341,18 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION bool = __or_, is_function<_To>, is_array<_To>>::value> struct __is_convertible_helper - { typedef typename is_void<_To>::type type; }; + { + typedef typename is_void<_To>::type type; +#if __cplusplus > 201703L + typedef type __is_nothrow_type; +#endif + }; template class __is_convertible_helper<_From, _To, false> { - template - static void __test_aux(_To1); + template + static void __test_aux(_To1) noexcept; template(std::declval<_From1>()))> @@ -1358,8 +1363,23 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION static false_type __test(...); +#if __cplusplus > 201703L + template(std::declval<_From1>()))> + static __bool_constant<_NoEx> + __test_nothrow(int); + + template + static false_type + __test_nothrow(...); +#endif + public: typedef decltype(__test<_From, _To>(0)) type; + +#if __cplusplus > 201703L + typedef decltype(__test_nothrow<_From, _To>(0)) __is_nothrow_type; +#endif }; @@ -1369,6 +1389,18 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION : public __is_convertible_helper<_From, _To>::type { }; +#if __cplusplus > 201703L + /// is_nothrow_convertible + template + struct is_nothrow_convertible + : public __is_convertible_helper<_From, _To>::__is_nothrow_type + { }; + + /// is_nothrow_convertible_v + template + inline constexpr bool is_nothrow_convertible_v + = is_nothrow_convertible<_From, _To>::value; +#endif // C++2a // Const-volatile modifications. diff --git a/libstdc++-v3/testsuite/20_util/is_nothrow_convertible/requirements/explicit_instantiation.cc b/libstdc++-v3/testsuite/20_util/is_nothrow_convertible/requirements/explicit_instantiation.cc new file mode 100644 index 00000000000..68f1adecb38 --- /dev/null +++ b/libstdc++-v3/testsuite/20_util/is_nothrow_convertible/requirements/explicit_instantiation.cc @@ -0,0 +1,29 @@ +// Copyright (C) 2018 Free Software Foundation, Inc. +// +// This file is part of the GNU ISO C++ Library. This library is free +// software; you can redistribute it and/or modify it under the +// terms of the GNU General Public License as published by the +// Free Software Foundation; either version 3, or (at your option) +// any later version. + +// This library is distributed in the hope that it will be useful, +// but WITHOUT ANY WARRANTY; without even the implied warranty of +// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the +// GNU General Public License for more details. + +// You should have received a copy of the GNU General Public License along +// with this library; see the file COPYING3. If not see +// . + +// { dg-options "-std=gnu++2a" } +// { dg-do compile { target c++2a } } + +// NB: This file is for testing type_traits with NO OTHER INCLUDES. + +#include + +namespace std +{ + typedef short test_type; + template struct is_nothrow_convertible; +} diff --git a/libstdc++-v3/testsuite/20_util/is_nothrow_convertible/requirements/typedefs.cc b/libstdc++-v3/testsuite/20_util/is_nothrow_convertible/requirements/typedefs.cc new file mode 100644 index 00000000000..3b5c6d51fe1 --- /dev/null +++ b/libstdc++-v3/testsuite/20_util/is_nothrow_convertible/requirements/typedefs.cc @@ -0,0 +1,33 @@ +// Copyright (C) 2018 Free Software Foundation, Inc. +// +// This file is part of the GNU ISO C++ Library. This library is free +// software; you can redistribute it and/or modify it under the +// terms of the GNU General Public License as published by the +// Free Software Foundation; either version 3, or (at your option) +// any later version. +// +// This library is distributed in the hope that it will be useful, +// but WITHOUT ANY WARRANTY; without even the implied warranty of +// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the +// GNU General Public License for more details. +// +// You should have received a copy of the GNU General Public License along +// with this library; see the file COPYING3. If not see +// . + +// { dg-options "-std=gnu++2a" } +// { dg-do compile { target c++2a } } + +// NB: This file is for testing type_traits with NO OTHER INCLUDES. + +#include + +void test01() +{ + // Check for required typedefs + typedef std::is_nothrow_convertible test_type; + typedef test_type::value_type value_type; + typedef test_type::type type; + typedef test_type::type::value_type type_value_type; + typedef test_type::type::type type_type; +} diff --git a/libstdc++-v3/testsuite/20_util/is_nothrow_convertible/value.cc b/libstdc++-v3/testsuite/20_util/is_nothrow_convertible/value.cc new file mode 100644 index 00000000000..5824be4810d --- /dev/null +++ b/libstdc++-v3/testsuite/20_util/is_nothrow_convertible/value.cc @@ -0,0 +1,177 @@ +// Copyright (C) 2018 Free Software Foundation, Inc. +// +// This file is part of the GNU ISO C++ Library. This library is free +// software; you can redistribute it and/or modify it under the +// terms of the GNU General Public License as published by the +// Free Software Foundation; either version 3, or (at your option) +// any later version. +// +// This library is distributed in the hope that it will be useful, +// but WITHOUT ANY WARRANTY; without even the implied warranty of +// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the +// GNU General Public License for more details. +// +// You should have received a copy of the GNU General Public License along +// with this library; see the file COPYING3. If not see +// . + +// { dg-options "-std=gnu++2a" } +// { dg-do compile { target c++2a } } + +#include +#include + +void test01() +{ + using std::is_nothrow_convertible; + using namespace __gnu_test; + + // Positive conversion tests. + static_assert(test_relationship(true)); + static_assert(test_relationship(true)); + static_assert(test_relationship(true)); + static_assert(test_relationship(true)); + static_assert(test_relationship(true)); + static_assert(test_relationship(true)); + static_assert(test_relationship(true)); + static_assert(test_relationship(true)); + static_assert(test_relationship(true)); + static_assert(test_relationship(true)); + static_assert(test_relationship(true)); + static_assert(test_relationship(true)); + static_assert(test_relationship(true)); + static_assert(test_relationship(true)); + static_assert(test_relationship(true)); + static_assert(test_relationship(true)); + static_assert(test_relationship(true)); + static_assert(test_relationship(true)); + static_assert(test_relationship(true)); + static_assert(test_relationship(true)); + + static_assert(test_relationship(true)); + + static_assert(test_relationship(true)); + static_assert(test_relationship(true)); + static_assert(test_relationship(true)); + static_assert(test_relationship(true)); + static_assert(test_relationship(true)); + static_assert(test_relationship(true)); + static_assert(test_relationship(true)); + static_assert(test_relationship(true)); + + static_assert(test_relationship(true)); + + // Negative conversion tests. + static_assert(test_relationship(false)); + static_assert(test_relationship(false)); + static_assert(test_relationship(false)); + static_assert(test_relationship(false)); + static_assert(test_relationship(false)); + static_assert(test_relationship(false)); + static_assert(test_relationship(false)); + static_assert(test_relationship(false)); + static_assert(test_relationship(false)); + static_assert(test_relationship(false)); + static_assert(test_relationship(false)); + static_assert(test_relationship(false)); + static_assert(test_relationship(false)); + static_assert(test_relationship(false)); + static_assert(test_relationship(false)); + + static_assert(test_relationship(false)); + static_assert(test_relationship(false)); + static_assert(test_relationship(false)); + + // C++0x + static_assert(test_relationship(false)); + static_assert(test_relationship(false)); + + static_assert(test_relationship(false)); + static_assert(test_relationship(false)); + static_assert(test_relationship(false)); + static_assert(test_relationship(false)); + static_assert(test_relationship(false)); + static_assert(test_relationship(false)); + static_assert(test_relationship(false)); + + static_assert(test_relationship(false)); + static_assert(test_relationship(false)); + static_assert(test_relationship(false)); + static_assert(test_relationship(false)); + static_assert(test_relationship(false)); + static_assert(test_relationship(false)); +} 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 13bca19c7e0..1380fc55c82 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 @@ -47,4 +47,4 @@ void test01() // { dg-error "required from here" "" { target *-*-* } 39 } // { dg-error "required from here" "" { target *-*-* } 41 } -// { dg-error "invalid use of incomplete type" "" { target *-*-* } 1793 } +// { dg-error "invalid use of incomplete type" "" { target *-*-* } 1825 } 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 9df01550ea3..cbc5300c182 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 @@ -47,5 +47,5 @@ void test01() // { dg-error "required from here" "" { target *-*-* } 39 } // { dg-error "required from here" "" { target *-*-* } 41 } -// { dg-error "invalid use of incomplete type" "" { target *-*-* } 1676 } +// { dg-error "invalid use of incomplete type" "" { target *-*-* } 1708 } -- 2.30.2