This adds a tag parameter to the tuple base class constructors that are used to implement uses-allocator construction but currently only have a single parameter, ensuring they are not viable candidates when calling a single-argument constructor.
Tested x86_64-linux, committed to trunk. I plan to fix this on the release branches too at some point.
commit 007f346ea8b17e323fedba0c425f80ee3f8fddee Author: Jonathan Wakely <jwak...@redhat.com> Date: Tue Jul 29 16:35:10 2014 +0100 PR libstdc++/61947 * include/std/tuple (_Head_base): Use allocator_arg_t parameters to disambiguate unary constructors. (_Tuple_impl): Pass allocator_arg_t arguments. * testsuite/20_util/tuple/61947.cc: New. * testsuite/20_util/uses_allocator/cons_neg.cc: Adjust dg-error line. diff --git a/libstdc++-v3/include/std/tuple b/libstdc++-v3/include/std/tuple index ef8aa5a..6c1032f 100644 --- a/libstdc++-v3/include/std/tuple +++ b/libstdc++-v3/include/std/tuple @@ -61,21 +61,22 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION constexpr _Head_base(const _Head& __h) : _Head(__h) { } - template<typename _UHead, typename = typename - enable_if<!is_convertible<_UHead, - __uses_alloc_base>::value>::type> + constexpr _Head_base(const _Head_base&) = default; + constexpr _Head_base(_Head_base&&) = default; + + template<typename _UHead> constexpr _Head_base(_UHead&& __h) : _Head(std::forward<_UHead>(__h)) { } - _Head_base(__uses_alloc0) + _Head_base(allocator_arg_t, __uses_alloc0) : _Head() { } template<typename _Alloc> - _Head_base(__uses_alloc1<_Alloc> __a) + _Head_base(allocator_arg_t, __uses_alloc1<_Alloc> __a) : _Head(allocator_arg, *__a._M_a) { } template<typename _Alloc> - _Head_base(__uses_alloc2<_Alloc> __a) + _Head_base(allocator_arg_t, __uses_alloc2<_Alloc> __a) : _Head(*__a._M_a) { } template<typename _UHead> @@ -106,21 +107,22 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION constexpr _Head_base(const _Head& __h) : _M_head_impl(__h) { } - template<typename _UHead, typename = typename - enable_if<!is_convertible<_UHead, - __uses_alloc_base>::value>::type> + constexpr _Head_base(const _Head_base&) = default; + constexpr _Head_base(_Head_base&&) = default; + + template<typename _UHead> constexpr _Head_base(_UHead&& __h) : _M_head_impl(std::forward<_UHead>(__h)) { } - _Head_base(__uses_alloc0) + _Head_base(allocator_arg_t, __uses_alloc0) : _M_head_impl() { } template<typename _Alloc> - _Head_base(__uses_alloc1<_Alloc> __a) + _Head_base(allocator_arg_t, __uses_alloc1<_Alloc> __a) : _M_head_impl(allocator_arg, *__a._M_a) { } template<typename _Alloc> - _Head_base(__uses_alloc2<_Alloc> __a) + _Head_base(allocator_arg_t, __uses_alloc2<_Alloc> __a) : _M_head_impl(*__a._M_a) { } template<typename _UHead> @@ -258,7 +260,7 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION template<typename _Alloc> _Tuple_impl(allocator_arg_t __tag, const _Alloc& __a) : _Inherited(__tag, __a), - _Base(__use_alloc<_Head>(__a)) { } + _Base(__tag, __use_alloc<_Head>(__a)) { } template<typename _Alloc> _Tuple_impl(allocator_arg_t __tag, const _Alloc& __a, diff --git a/libstdc++-v3/testsuite/20_util/tuple/61947.cc b/libstdc++-v3/testsuite/20_util/tuple/61947.cc new file mode 100644 index 0000000..7e77de6 --- /dev/null +++ b/libstdc++-v3/testsuite/20_util/tuple/61947.cc @@ -0,0 +1,29 @@ +// { dg-options "-std=gnu++11" } +// { dg-do compile } + +// Copyright (C) 2014 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 +// <http://www.gnu.org/licenses/>. + +#include <tuple> + +struct ConvertibleToAny { + template <class T> operator T() const { return T(); } +}; + +int main() { + std::tuple<ConvertibleToAny&&> t(ConvertibleToAny{}); +} diff --git a/libstdc++-v3/testsuite/20_util/uses_allocator/cons_neg.cc b/libstdc++-v3/testsuite/20_util/uses_allocator/cons_neg.cc index cf5d6a57..6396e26 100644 --- a/libstdc++-v3/testsuite/20_util/uses_allocator/cons_neg.cc +++ b/libstdc++-v3/testsuite/20_util/uses_allocator/cons_neg.cc @@ -44,4 +44,4 @@ void test01() tuple<Type> t(allocator_arg, a, 1); } -// { dg-error "no matching function" "" { target *-*-* } 91 } +// { dg-error "no matching function" "" { target *-*-* } 92 }