From: Jonathan Wakely Date: Mon, 17 Oct 2016 12:00:38 +0000 (+0100) Subject: Implement P0084R2, Emplace return type, for C++17 X-Git-Url: https://git.libre-soc.org/?a=commitdiff_plain;h=594ef205ae28bdd8d32ff141b41cc08158b84552;p=gcc.git Implement P0084R2, Emplace return type, for C++17 * doc/xml/manual/status_cxx2017.xml: Update status. * doc/html/*: Regenerate. * include/bits/deque.tcc (deque::emplace_front, deque::emplace_back): Return a reference in C++17 mode. * include/bits/forward_list.h (forward_list::emplace_front): Likewise. * include/bits/stl_bvector.h (vector::emplace_back): Likewise. * include/bits/stl_deque.h (deque::emplace_front, deque::emplace_back): Likewise. * include/bits/stl_list.h (list::emplace_front, list::emplace_back): Likewise. * include/bits/stl_queue.h (queue::emplace): Likewise. * include/bits/stl_stack.h (stack::emplace): Likewise. * include/bits/stl_vector.h (vector::emplace_back): Likewise. * include/bits/vector.tcc (vector::emplace_back): Likewise. * include/debug/deque (__gnu_debug::deque::emplace_front) (__gnu_debug::deque::emplace_back): Likewise. * include/debug/vector (__gnu_debug::vector::emplace_back): Likewise. * testsuite/23_containers/deque/modifiers/emplace/cxx17_return.cc: New. * testsuite/23_containers/forward_list/modifiers/ emplace_cxx17_return.cc: New. * testsuite/23_containers/list/modifiers/emplace/cxx17_return.cc: New. * testsuite/23_containers/queue/members/emplace_cxx17_return.cc: New. * testsuite/23_containers/stack/members/emplace_cxx17_return.cc: New. * testsuite/23_containers/vector/bool/emplace_cxx17_return.cc: New. * testsuite/23_containers/vector/modifiers/emplace/cxx17_return.cc: New. From-SVN: r241234 --- diff --git a/libstdc++-v3/ChangeLog b/libstdc++-v3/ChangeLog index 5f72a961ca9..b31c1dd331a 100644 --- a/libstdc++-v3/ChangeLog +++ b/libstdc++-v3/ChangeLog @@ -1,3 +1,33 @@ +2016-10-17 Jonathan Wakely + + * doc/xml/manual/status_cxx2017.xml: Update status. + * doc/html/*: Regenerate. + * include/bits/deque.tcc (deque::emplace_front, deque::emplace_back): + Return a reference in C++17 mode. + * include/bits/forward_list.h (forward_list::emplace_front): Likewise. + * include/bits/stl_bvector.h (vector::emplace_back): Likewise. + * include/bits/stl_deque.h (deque::emplace_front, deque::emplace_back): + Likewise. + * include/bits/stl_list.h (list::emplace_front, list::emplace_back): + Likewise. + * include/bits/stl_queue.h (queue::emplace): Likewise. + * include/bits/stl_stack.h (stack::emplace): Likewise. + * include/bits/stl_vector.h (vector::emplace_back): Likewise. + * include/bits/vector.tcc (vector::emplace_back): Likewise. + * include/debug/deque (__gnu_debug::deque::emplace_front) + (__gnu_debug::deque::emplace_back): Likewise. + * include/debug/vector (__gnu_debug::vector::emplace_back): Likewise. + * testsuite/23_containers/deque/modifiers/emplace/cxx17_return.cc: + New. + * testsuite/23_containers/forward_list/modifiers/ + emplace_cxx17_return.cc: New. + * testsuite/23_containers/list/modifiers/emplace/cxx17_return.cc: New. + * testsuite/23_containers/queue/members/emplace_cxx17_return.cc: New. + * testsuite/23_containers/stack/members/emplace_cxx17_return.cc: New. + * testsuite/23_containers/vector/bool/emplace_cxx17_return.cc: New. + * testsuite/23_containers/vector/modifiers/emplace/cxx17_return.cc: + New. + 2016-10-16 Paolo Carlini * testsuite/22_locale/classification/isblank.cc: Remove 'test' diff --git a/libstdc++-v3/doc/html/manual/status.html b/libstdc++-v3/doc/html/manual/status.html index 5ef66daa494..7a79f0d83b0 100644 --- a/libstdc++-v3/doc/html/manual/status.html +++ b/libstdc++-v3/doc/html/manual/status.html @@ -706,11 +706,11 @@ Feature-testing recommendations for C++. 6.2 (3.0) __cpp_lib_incomplete_container_elements >= 201505 (the feature was always supported, but the macro was not defined until GCC 6.2) - Emplace return type + Emplace return type P0084R2 - No  Improved insertion interface for unique-key maps + 7  Improved insertion interface for unique-key maps N4279 diff --git a/libstdc++-v3/doc/html/manual/test.html b/libstdc++-v3/doc/html/manual/test.html index 9e5b64fa151..f37d7be8a47 100644 --- a/libstdc++-v3/doc/html/manual/test.html +++ b/libstdc++-v3/doc/html/manual/test.html @@ -322,7 +322,7 @@ cat 27_io/objects/char/3_xin.in | a.out
make, or via options for the DejaGnu test framework (described below). The latter approach uses the --target_board option that was shown earlier. - For example, to run the tests with -O1 -D_GLIBCXX_ASSERT + For example, to run the tests with -O1 -D_GLIBCXX_ASSERTIONS you could use: 

    make RUNTESTFLAGS=--target_board=unix/-O1/-D_GLIBCXX_ASSERTIONS

diff --git a/libstdc++-v3/doc/xml/manual/status_cxx2017.xml b/libstdc++-v3/doc/xml/manual/status_cxx2017.xml index ae8dfa9529b..a1190bc1afa 100644 --- a/libstdc++-v3/doc/xml/manual/status_cxx2017.xml +++ b/libstdc++-v3/doc/xml/manual/status_cxx2017.xml @@ -542,14 +542,13 @@ Feature-testing recommendations for C++. - Emplace return type P0084R2 - No + 7 diff --git a/libstdc++-v3/include/bits/deque.tcc b/libstdc++-v3/include/bits/deque.tcc index 96ec9f82d8f..796b0cd9239 100644 --- a/libstdc++-v3/include/bits/deque.tcc +++ b/libstdc++-v3/include/bits/deque.tcc @@ -129,7 +129,11 @@ _GLIBCXX_BEGIN_NAMESPACE_CONTAINER #if __cplusplus >= 201103L template template +#if __cplusplus > 201402L + typename deque<_Tp, _Alloc>::reference +#else void +#endif deque<_Tp, _Alloc>:: emplace_front(_Args&&... __args) { @@ -142,11 +146,18 @@ _GLIBCXX_BEGIN_NAMESPACE_CONTAINER } else _M_push_front_aux(std::forward<_Args>(__args)...); +#if __cplusplus > 201402L + return front(); +#endif } template template +#if __cplusplus > 201402L + typename deque<_Tp, _Alloc>::reference +#else void +#endif deque<_Tp, _Alloc>:: emplace_back(_Args&&... __args) { @@ -160,6 +171,9 @@ _GLIBCXX_BEGIN_NAMESPACE_CONTAINER } else _M_push_back_aux(std::forward<_Args>(__args)...); +#if __cplusplus > 201402L + return back(); +#endif } #endif diff --git a/libstdc++-v3/include/bits/forward_list.h b/libstdc++-v3/include/bits/forward_list.h index 39615094131..0ea88063d7e 100644 --- a/libstdc++-v3/include/bits/forward_list.h +++ b/libstdc++-v3/include/bits/forward_list.h @@ -797,10 +797,19 @@ _GLIBCXX_BEGIN_NAMESPACE_CONTAINER * and references. */ template - void +#if __cplusplus > 201402L + reference +#else + void +#endif emplace_front(_Args&&... __args) - { this->_M_insert_after(cbefore_begin(), - std::forward<_Args>(__args)...); } + { + this->_M_insert_after(cbefore_begin(), + std::forward<_Args>(__args)...); +#if __cplusplus > 201402L + return front(); +#endif + } /** * @brief Add data to the front of the %forward_list. diff --git a/libstdc++-v3/include/bits/stl_bvector.h b/libstdc++-v3/include/bits/stl_bvector.h index b3ac63f521f..2e231b9d86b 100644 --- a/libstdc++-v3/include/bits/stl_bvector.h +++ b/libstdc++-v3/include/bits/stl_bvector.h @@ -1056,9 +1056,18 @@ template #if __cplusplus >= 201103L template +#if __cplusplus > 201402L + reference +#else void +#endif emplace_back(_Args&&... __args) - { push_back(bool(__args...)); } + { + push_back(bool(__args...)); +#if __cplusplus > 201402L + return back(); +#endif + } template iterator diff --git a/libstdc++-v3/include/bits/stl_deque.h b/libstdc++-v3/include/bits/stl_deque.h index 7192f65a1c0..8539a08f3a9 100644 --- a/libstdc++-v3/include/bits/stl_deque.h +++ b/libstdc++-v3/include/bits/stl_deque.h @@ -1519,7 +1519,11 @@ _GLIBCXX_BEGIN_NAMESPACE_CONTAINER { emplace_front(std::move(__x)); } template - void +#if __cplusplus > 201402L + reference +#else + void +#endif emplace_front(_Args&&... __args); #endif @@ -1552,7 +1556,11 @@ _GLIBCXX_BEGIN_NAMESPACE_CONTAINER { emplace_back(std::move(__x)); } template - void +#if __cplusplus > 201402L + reference +#else + void +#endif emplace_back(_Args&&... __args); #endif diff --git a/libstdc++-v3/include/bits/stl_list.h b/libstdc++-v3/include/bits/stl_list.h index 87c8a393d7c..8693a6f55c6 100644 --- a/libstdc++-v3/include/bits/stl_list.h +++ b/libstdc++-v3/include/bits/stl_list.h @@ -1069,9 +1069,18 @@ _GLIBCXX_BEGIN_NAMESPACE_CXX11 { this->_M_insert(begin(), std::move(__x)); } template - void +#if __cplusplus > 201402L + reference +#else + void +#endif emplace_front(_Args&&... __args) - { this->_M_insert(begin(), std::forward<_Args>(__args)...); } + { + this->_M_insert(begin(), std::forward<_Args>(__args)...); +#if __cplusplus > 201402L + return front(); +#endif + } #endif /** @@ -1110,9 +1119,18 @@ _GLIBCXX_BEGIN_NAMESPACE_CXX11 { this->_M_insert(end(), std::move(__x)); } template - void +#if __cplusplus > 201402L + reference +#else + void +#endif emplace_back(_Args&&... __args) - { this->_M_insert(end(), std::forward<_Args>(__args)...); } + { + this->_M_insert(end(), std::forward<_Args>(__args)...); +#if __cplusplus > 201402L + return back(); +#endif + } #endif /** diff --git a/libstdc++-v3/include/bits/stl_queue.h b/libstdc++-v3/include/bits/stl_queue.h index 843199c5b06..178e4b2c22b 100644 --- a/libstdc++-v3/include/bits/stl_queue.h +++ b/libstdc++-v3/include/bits/stl_queue.h @@ -247,10 +247,17 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION push(value_type&& __x) { c.push_back(std::move(__x)); } +#if __cplusplus > 201402L + template + decltype(auto) + emplace(_Args&&... __args) + { return c.emplace_back(std::forward<_Args>(__args)...); } +#else template void emplace(_Args&&... __args) { c.emplace_back(std::forward<_Args>(__args)...); } +#endif #endif /** diff --git a/libstdc++-v3/include/bits/stl_stack.h b/libstdc++-v3/include/bits/stl_stack.h index 612913da935..ebc8816d56a 100644 --- a/libstdc++-v3/include/bits/stl_stack.h +++ b/libstdc++-v3/include/bits/stl_stack.h @@ -223,10 +223,17 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION push(value_type&& __x) { c.push_back(std::move(__x)); } +#if __cplusplus > 201402L + template + decltype(auto) + emplace(_Args&&... __args) + { return c.emplace_back(std::forward<_Args>(__args)...); } +#else template void emplace(_Args&&... __args) { c.emplace_back(std::forward<_Args>(__args)...); } +#endif #endif /** diff --git a/libstdc++-v3/include/bits/stl_vector.h b/libstdc++-v3/include/bits/stl_vector.h index 9a05dd54f7d..efc569b9c84 100644 --- a/libstdc++-v3/include/bits/stl_vector.h +++ b/libstdc++-v3/include/bits/stl_vector.h @@ -960,7 +960,11 @@ _GLIBCXX_BEGIN_NAMESPACE_CONTAINER { emplace_back(std::move(__x)); } template +#if __cplusplus > 201402L + reference +#else void +#endif emplace_back(_Args&&... __args); #endif diff --git a/libstdc++-v3/include/bits/vector.tcc b/libstdc++-v3/include/bits/vector.tcc index 6926a8b91c4..b6050d34cc9 100644 --- a/libstdc++-v3/include/bits/vector.tcc +++ b/libstdc++-v3/include/bits/vector.tcc @@ -87,7 +87,11 @@ _GLIBCXX_BEGIN_NAMESPACE_CONTAINER #if __cplusplus >= 201103L template template +#if __cplusplus > 201402L + typename vector<_Tp, _Alloc>::reference +#else void +#endif vector<_Tp, _Alloc>:: emplace_back(_Args&&... __args) { @@ -99,6 +103,9 @@ _GLIBCXX_BEGIN_NAMESPACE_CONTAINER } else _M_realloc_insert(end(), std::forward<_Args>(__args)...); +#if __cplusplus > 201402L + return back(); +#endif } #endif diff --git a/libstdc++-v3/include/debug/deque b/libstdc++-v3/include/debug/deque index f15faadbb7b..bf4cba6e725 100644 --- a/libstdc++-v3/include/debug/deque +++ b/libstdc++-v3/include/debug/deque @@ -386,19 +386,33 @@ namespace __debug { emplace_back(std::move(__x)); } template +#if __cplusplus > 201402L + reference +#else void +#endif emplace_front(_Args&&... __args) { _Base::emplace_front(std::forward<_Args>(__args)...); this->_M_invalidate_all(); +#if __cplusplus > 201402L + return front(); +#endif } template +#if __cplusplus > 201402L + reference +#else void +#endif emplace_back(_Args&&... __args) { _Base::emplace_back(std::forward<_Args>(__args)...); this->_M_invalidate_all(); +#if __cplusplus > 201402L + return back(); +#endif } template diff --git a/libstdc++-v3/include/debug/vector b/libstdc++-v3/include/debug/vector index 9bcda733a70..b2d70bd5f6b 100644 --- a/libstdc++-v3/include/debug/vector +++ b/libstdc++-v3/include/debug/vector @@ -478,7 +478,11 @@ namespace __debug { emplace_back(std::move(__x)); } template +#if __cplusplus > 201402L + deque<_Tp, _Alloc>::reference +#else void +#endif emplace_back(_Args&&... __args) { bool __realloc = this->_M_requires_reallocation(this->size() + 1); @@ -486,6 +490,9 @@ namespace __debug if (__realloc) this->_M_invalidate_all(); this->_M_update_guaranteed_capacity(); +#if __cplusplus > 201402L + return back(); +#endif } #endif diff --git a/libstdc++-v3/testsuite/23_containers/deque/modifiers/emplace/cxx17_return.cc b/libstdc++-v3/testsuite/23_containers/deque/modifiers/emplace/cxx17_return.cc new file mode 100644 index 00000000000..3e5da960297 --- /dev/null +++ b/libstdc++-v3/testsuite/23_containers/deque/modifiers/emplace/cxx17_return.cc @@ -0,0 +1,49 @@ +// Copyright (C) 2016 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++17" } +// { dg-do run { target c++1z } } + +#include +#include + +using test_type = std::deque; + +void +test01() +{ + test_type x{1, 2, 3, 4}; + test_type::reference r = x.emplace_front(0); + VERIFY( r == 0 ); + VERIFY( &r == &x.front() ); +} + +void +test02() +{ + test_type x{1, 2, 3, 4}; + test_type::reference r = x.emplace_back(5); + VERIFY( r == 5 ); + VERIFY( &r == &x.back() ); +} + +int +main() +{ + test01(); + test02(); +} diff --git a/libstdc++-v3/testsuite/23_containers/forward_list/modifiers/emplace_cxx17_return.cc b/libstdc++-v3/testsuite/23_containers/forward_list/modifiers/emplace_cxx17_return.cc new file mode 100644 index 00000000000..b91c1ca3397 --- /dev/null +++ b/libstdc++-v3/testsuite/23_containers/forward_list/modifiers/emplace_cxx17_return.cc @@ -0,0 +1,39 @@ +// Copyright (C) 2016 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++17" } +// { dg-do run { target c++1z } } + +#include +#include + +using test_type = std::forward_list; + +void +test01() +{ + test_type x{1, 2, 3, 4}; + test_type::reference r = x.emplace_front(0); + VERIFY( r == 0 ); + VERIFY( &r == &x.front() ); +} + +int +main() +{ + test01(); +} diff --git a/libstdc++-v3/testsuite/23_containers/list/modifiers/emplace/cxx17_return.cc b/libstdc++-v3/testsuite/23_containers/list/modifiers/emplace/cxx17_return.cc new file mode 100644 index 00000000000..c88d8d2426c --- /dev/null +++ b/libstdc++-v3/testsuite/23_containers/list/modifiers/emplace/cxx17_return.cc @@ -0,0 +1,49 @@ +// Copyright (C) 2016 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++17" } +// { dg-do run { target c++1z } } + +#include +#include + +using test_type = std::list; + +void +test01() +{ + test_type x{1, 2, 3, 4}; + test_type::reference r = x.emplace_front(0); + VERIFY( r == 0 ); + VERIFY( &r == &x.front() ); +} + +void +test02() +{ + test_type x{1, 2, 3, 4}; + test_type::reference r = x.emplace_back(5); + VERIFY( r == 5 ); + VERIFY( &r == &x.back() ); +} + +int +main() +{ + test01(); + test02(); +} diff --git a/libstdc++-v3/testsuite/23_containers/queue/members/emplace_cxx17_return.cc b/libstdc++-v3/testsuite/23_containers/queue/members/emplace_cxx17_return.cc new file mode 100644 index 00000000000..a618e9ceb36 --- /dev/null +++ b/libstdc++-v3/testsuite/23_containers/queue/members/emplace_cxx17_return.cc @@ -0,0 +1,39 @@ +// Copyright (C) 2016 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++17" } +// { dg-do run { target c++1z } } + +#include +#include + +using test_type = std::queue; + +void +test01() +{ + test_type x{ test_type::container_type{1, 2, 3, 4} }; + test_type::reference r = x.emplace(5); + VERIFY( r == 5 ); + VERIFY( &r == &x.back() ); +} + +int +main() +{ + test01(); +} diff --git a/libstdc++-v3/testsuite/23_containers/stack/members/emplace_cxx17_return.cc b/libstdc++-v3/testsuite/23_containers/stack/members/emplace_cxx17_return.cc new file mode 100644 index 00000000000..76964ebe7a2 --- /dev/null +++ b/libstdc++-v3/testsuite/23_containers/stack/members/emplace_cxx17_return.cc @@ -0,0 +1,39 @@ +// Copyright (C) 2016 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++17" } +// { dg-do run { target c++1z } } + +#include +#include + +using test_type = std::stack; + +void +test01() +{ + test_type x{ test_type::container_type{1, 2, 3, 4} }; + test_type::reference r = x.emplace(5); + VERIFY( r == 5 ); + VERIFY( &r == &x.top() ); +} + +int +main() +{ + test01(); +} diff --git a/libstdc++-v3/testsuite/23_containers/vector/bool/emplace_cxx17_return.cc b/libstdc++-v3/testsuite/23_containers/vector/bool/emplace_cxx17_return.cc new file mode 100644 index 00000000000..d4f70fb0de9 --- /dev/null +++ b/libstdc++-v3/testsuite/23_containers/vector/bool/emplace_cxx17_return.cc @@ -0,0 +1,38 @@ +// Copyright (C) 2016 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++17" } +// { dg-do run { target c++1z } } + +#include +#include + +using test_type = std::vector; + +void +test02() +{ + test_type x{true, true}; + test_type::reference r = x.emplace_back(false); + VERIFY( r == false ); +} + +int +main() +{ + test02(); +} diff --git a/libstdc++-v3/testsuite/23_containers/vector/modifiers/emplace/cxx17_return.cc b/libstdc++-v3/testsuite/23_containers/vector/modifiers/emplace/cxx17_return.cc new file mode 100644 index 00000000000..9006dabbfc2 --- /dev/null +++ b/libstdc++-v3/testsuite/23_containers/vector/modifiers/emplace/cxx17_return.cc @@ -0,0 +1,39 @@ +// Copyright (C) 2016 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++17" } +// { dg-do run { target c++1z } } + +#include +#include + +using test_type = std::vector; + +void +test02() +{ + test_type x{1, 2, 3, 4}; + test_type::reference r = x.emplace_back(5); + VERIFY( r == 5 ); + VERIFY( &r == &x.back() ); +} + +int +main() +{ + test02(); +}