From d80f04d61e11a103e2e463a1a90a3d780b0fd99b Mon Sep 17 00:00:00 2001 From: Jonathan Wakely Date: Wed, 6 Mar 2019 11:32:42 +0000 Subject: [PATCH] Constexpr in std::pointer_traits (P1006R1) * include/bits/ptr_traits.h [C++20] (pointer_traits::pointer_to): Add constexpr. * testsuite/20_util/pointer_traits/pointer_to_constexpr.cc: New test. From-SVN: r269418 --- libstdc++-v3/ChangeLog | 6 +++++ libstdc++-v3/include/bits/ptr_traits.h | 2 +- .../pointer_traits/pointer_to_constexpr.cc | 27 +++++++++++++++++++ 3 files changed, 34 insertions(+), 1 deletion(-) create mode 100644 libstdc++-v3/testsuite/20_util/pointer_traits/pointer_to_constexpr.cc diff --git a/libstdc++-v3/ChangeLog b/libstdc++-v3/ChangeLog index 44bf6e72c65..053da2c25d8 100644 --- a/libstdc++-v3/ChangeLog +++ b/libstdc++-v3/ChangeLog @@ -1,3 +1,9 @@ +2019-03-06 Jonathan Wakely + + * include/bits/ptr_traits.h [C++20] (pointer_traits::pointer_to): + Add constexpr. + * testsuite/20_util/pointer_traits/pointer_to_constexpr.cc: New test. + 2019-03-05 Jonathan Wakely * include/c_compatibility/math.h [C++20] (lerp): Add using diff --git a/libstdc++-v3/include/bits/ptr_traits.h b/libstdc++-v3/include/bits/ptr_traits.h index 76355863852..c90a35080f1 100644 --- a/libstdc++-v3/include/bits/ptr_traits.h +++ b/libstdc++-v3/include/bits/ptr_traits.h @@ -137,7 +137,7 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION * @param __r A reference to an object of type @c element_type * @return @c addressof(__r) */ - static pointer + static _GLIBCXX20_CONSTEXPR pointer pointer_to(__make_not_void& __r) noexcept { return std::addressof(__r); } }; diff --git a/libstdc++-v3/testsuite/20_util/pointer_traits/pointer_to_constexpr.cc b/libstdc++-v3/testsuite/20_util/pointer_traits/pointer_to_constexpr.cc new file mode 100644 index 00000000000..ed4f2157adc --- /dev/null +++ b/libstdc++-v3/testsuite/20_util/pointer_traits/pointer_to_constexpr.cc @@ -0,0 +1,27 @@ +// Copyright (C) 2019 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 + +int i = 0; +static_assert( std::pointer_traits::pointer_to(i) == &i ); + +struct X { } x; +static_assert( std::pointer_traits::pointer_to(x) == &x ); -- 2.30.2