From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: by sourceware.org (Postfix, from userid 2140) id EB5593890431; Wed, 22 Jul 2020 07:50:53 +0000 (GMT) DKIM-Filter: OpenDKIM Filter v2.11.0 sourceware.org EB5593890431 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gcc.gnu.org; s=default; t=1595404253; bh=igC+a6Obl30VOdMWmDpmv+GRRUroh0MNdeoPuoa+4SQ=; h=From:To:Subject:Date:From; b=ZiBtYQNKahXMCEjIh2VHps5jGFtPTQ+IP0CFCMfTxXRYCywDi5wlYLFfcaX+5O+Ra MR9wr698LxUDlb3lMcR51phq/WKu8soPKcLihuJbsBrbcVr9/4xc8lSdkp8DKBXkXz El3zgGwblrTg1pi2YUv0l2OYEOFc+MiFolBK7FjM= Content-Type: text/plain; charset="us-ascii" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit From: Alexandre Oliva To: gcc-cvs@gcc.gnu.org, libstdc++-cvs@gcc.gnu.org Subject: [gcc(refs/users/aoliva/heads/testbase)] libstdc++: Constrain std::make_optional X-Act-Checkin: gcc X-Git-Author: Jonathan Wakely X-Git-Refname: refs/users/aoliva/heads/testbase X-Git-Oldrev: 8992cd1892df1adb352cf5d5b279a00686d1e88a X-Git-Newrev: bcfe4681f9be68f96f0610f30356510ff518806b Message-Id: <20200722075053.EB5593890431@sourceware.org> Date: Wed, 22 Jul 2020 07:50:53 +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, 22 Jul 2020 07:50:54 -0000 https://gcc.gnu.org/g:bcfe4681f9be68f96f0610f30356510ff518806b commit bcfe4681f9be68f96f0610f30356510ff518806b Author: Jonathan Wakely Date: Mon Jul 6 21:54:12 2020 +0100 libstdc++: Constrain std::make_optional The standard rquires that std::make_optional is constrained similarly to the std::optional constructors, which our implementation fails to do. As a conforming extension this also adds a noexcept-specifier to each std::make_optional overload. libstdc++-v3/ChangeLog: * include/std/optional (make_optional): Add enable_if constraints and noexcept-specifier to each overload. * testsuite/20_util/optional/make_optional-2.cc: New test. Diff: --- libstdc++-v3/include/std/optional | 25 ++++-- .../testsuite/20_util/optional/make_optional-2.cc | 94 ++++++++++++++++++++++ 2 files changed, 111 insertions(+), 8 deletions(-) diff --git a/libstdc++-v3/include/std/optional b/libstdc++-v3/include/std/optional index 785c434412d..24821f81d0f 100644 --- a/libstdc++-v3/include/std/optional +++ b/libstdc++-v3/include/std/optional @@ -1220,19 +1220,28 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION swap(optional<_Tp>&, optional<_Tp>&) = delete; template - constexpr optional> + constexpr + enable_if_t, _Tp>, + optional>> make_optional(_Tp&& __t) - { return optional> { std::forward<_Tp>(__t) }; } + noexcept(is_nothrow_constructible_v>, _Tp>) + { return optional>{ std::forward<_Tp>(__t) }; } - template - constexpr optional<_Tp> + template + constexpr + enable_if_t, + optional<_Tp>> make_optional(_Args&&... __args) - { return optional<_Tp> { in_place, std::forward<_Args>(__args)... }; } + noexcept(is_nothrow_constructible_v<_Tp, _Args...>) + { return optional<_Tp>{ in_place, std::forward<_Args>(__args)... }; } - template - constexpr optional<_Tp> + template + constexpr + enable_if_t&, _Args...>, + optional<_Tp>> make_optional(initializer_list<_Up> __il, _Args&&... __args) - { return optional<_Tp> { in_place, __il, std::forward<_Args>(__args)... }; } + noexcept(is_nothrow_constructible_v<_Tp, initializer_list<_Up>&, _Args...>) + { return optional<_Tp>{ in_place, __il, std::forward<_Args>(__args)... }; } // Hash. diff --git a/libstdc++-v3/testsuite/20_util/optional/make_optional-2.cc b/libstdc++-v3/testsuite/20_util/optional/make_optional-2.cc new file mode 100644 index 00000000000..65a1fc78d80 --- /dev/null +++ b/libstdc++-v3/testsuite/20_util/optional/make_optional-2.cc @@ -0,0 +1,94 @@ +// { dg-do compile { target c++17 } } + +// 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 +// . + +#include + +int i; + +struct Cont +{ + Cont() noexcept; + Cont(Cont&&) noexcept; + Cont(const Cont&); + Cont(int); + Cont(std::initializer_list, int) noexcept; + Cont(std::initializer_list, const char*); +}; +const Cont c{}; + +template + struct can_make_optional1 + : std::false_type + { }; + +template + struct can_make_optional1()))>> + : std::true_type + { }; + +static_assert( can_make_optional1::value ); +static_assert( noexcept(std::make_optional(1)) ); +static_assert( can_make_optional1::value ); +static_assert( noexcept(std::make_optional(i)) ); +static_assert( ! can_make_optional1::value ); +static_assert( can_make_optional1::value ); +static_assert( noexcept(std::make_optional(Cont{})) ); +static_assert( can_make_optional1::value ); +static_assert( ! noexcept(std::make_optional(c)) ); + +template + struct can_make_optional2 + : std::false_type + { }; + +template + struct can_make_optional2(std::declval()))>> + : std::true_type + { }; + +static_assert( can_make_optional2::value ); +static_assert( noexcept(std::make_optional(1)) ); +static_assert( can_make_optional2::value ); +static_assert( noexcept(std::make_optional(i)) ); +static_assert( ! can_make_optional2::value ); +static_assert( can_make_optional2::value ); +static_assert( noexcept(std::make_optional({})) ); +static_assert( can_make_optional2::value ); +static_assert( ! noexcept(std::make_optional(c)) ); +static_assert( can_make_optional2::value ); +static_assert( ! noexcept(std::make_optional(1)) ); + +template + struct can_make_optional3 + : std::false_type + { }; + +template + struct can_make_optional3({1,2}, std::declval()))>> + : std::true_type + { }; + +static_assert( can_make_optional3::value ); +static_assert( noexcept(std::make_optional({1,2}, 1)) ); +static_assert( can_make_optional3::value ); +static_assert( ! noexcept(std::make_optional({1,2}, "")) ); +static_assert( !can_make_optional3::value );