From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: by sourceware.org (Postfix, from userid 2181) id BF0853844025; Wed, 1 Jul 2020 22:48:43 +0000 (GMT) DKIM-Filter: OpenDKIM Filter v2.11.0 sourceware.org BF0853844025 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gcc.gnu.org; s=default; t=1593643723; bh=TTzlNTA3pcQ8Xcq899KFgsrc3neHSBHNG5TaHMzgkY0=; h=From:To:Subject:Date:From; b=V+3jrZBGtLyX5nLoznhgxXTymWqMekYm+Zjd+wLuF+ca/iF3wCURtc2gA7hwZModC 1JZNEGEo0t51D48IGNvSBMDTLh9kbbXn9kmlLM/sd4LHYE2Xx5T62AMx8Nxd4QKTs4 FlUPRtcc0XaI99zKnAyi9pjOO+PV06ELWGA5n10Y= Content-Type: text/plain; charset="us-ascii" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit From: Jonathan Wakely To: gcc-cvs@gcc.gnu.org, libstdc++-cvs@gcc.gnu.org Subject: [gcc r10-8410] libstdc++: Strip cv-qualifiers in std::atomic (PR 95282) X-Act-Checkin: gcc X-Git-Author: Jonathan Wakely X-Git-Refname: refs/heads/releases/gcc-10 X-Git-Oldrev: 4c994586cbd40a33f223aaaf90887afe97208543 X-Git-Newrev: 161fb9dfc886afb70dcfb45a51571df5e3fce9eb Message-Id: <20200701224843.BF0853844025@sourceware.org> Date: Wed, 1 Jul 2020 22:48:43 +0000 (GMT) X-BeenThere: libstdc++-cvs@gcc.gnu.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Libstdc++-cvs mailing list List-Unsubscribe: , List-Archive: List-Help: List-Subscribe: , X-List-Received-Date: Wed, 01 Jul 2020 22:48:43 -0000 https://gcc.gnu.org/g:161fb9dfc886afb70dcfb45a51571df5e3fce9eb commit r10-8410-g161fb9dfc886afb70dcfb45a51571df5e3fce9eb Author: Jonathan Wakely Date: Wed May 27 22:55:21 2020 +0100 libstdc++: Strip cv-qualifiers in std::atomic (PR 95282) This squashes two commits, r11-674 and r11-1401. PR libstdc++/95282 * include/bits/atomic_base.h (__atomic_impl::load): Add const-qualifier to parameter so that _Tp is deduced as the non-const type, and use _Val to get the unqualified type. (__atomic_impl::exchange): Use the _Val alias to remove volatile from the reinterpret_cast result type. * testsuite/29_atomics/atomic_float/95282.cc: New test. (cherry picked from commit e40b11a91cb345db1324c3cb8f75b01e28056693) Diff: --- libstdc++-v3/include/bits/atomic_base.h | 10 +++---- .../testsuite/29_atomics/atomic_float/95282.cc | 35 ++++++++++++++++++++++ 2 files changed, 40 insertions(+), 5 deletions(-) diff --git a/libstdc++-v3/include/bits/atomic_base.h b/libstdc++-v3/include/bits/atomic_base.h index 87fe0bd6000..41d5928e482 100644 --- a/libstdc++-v3/include/bits/atomic_base.h +++ b/libstdc++-v3/include/bits/atomic_base.h @@ -850,21 +850,21 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION { __atomic_store(__ptr, std::__addressof(__t), int(__m)); } template - _GLIBCXX_ALWAYS_INLINE _Tp - load(_Tp* __ptr, memory_order __m) noexcept + _GLIBCXX_ALWAYS_INLINE _Val<_Tp> + load(const _Tp* __ptr, memory_order __m) noexcept { alignas(_Tp) unsigned char __buf[sizeof(_Tp)]; - _Tp* __dest = reinterpret_cast<_Tp*>(__buf); + auto* __dest = reinterpret_cast<_Val<_Tp>*>(__buf); __atomic_load(__ptr, __dest, int(__m)); return *__dest; } template - _GLIBCXX_ALWAYS_INLINE _Tp + _GLIBCXX_ALWAYS_INLINE _Val<_Tp> exchange(_Tp* __ptr, _Val<_Tp> __desired, memory_order __m) noexcept { alignas(_Tp) unsigned char __buf[sizeof(_Tp)]; - _Tp* __dest = reinterpret_cast<_Tp*>(__buf); + auto* __dest = reinterpret_cast<_Val<_Tp>*>(__buf); __atomic_exchange(__ptr, std::__addressof(__desired), __dest, int(__m)); return *__dest; } diff --git a/libstdc++-v3/testsuite/29_atomics/atomic_float/95282.cc b/libstdc++-v3/testsuite/29_atomics/atomic_float/95282.cc new file mode 100644 index 00000000000..2de751c6ad4 --- /dev/null +++ b/libstdc++-v3/testsuite/29_atomics/atomic_float/95282.cc @@ -0,0 +1,35 @@ +// Copyright (C) 2020 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 + +float +test01() +{ + std::atomic a; + return a.load(); +} + +float +test02() +{ + volatile std::atomic a; + return a.load(); +}