gcc/libstdc++-v3/testsuite/20_util/aligned_union/1.cc
2021-01-04 10:26:59 +01:00

72 lines
2.3 KiB
C++

// { dg-do compile { target c++11 } }
// 2014-04-16 Rüdiger Sonderfeld <ruediger@c-plusplus.de>
// Copyright (C) 2014-2021 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/>.
// C++11 [meta.trans.other] 20.9.7.6: aligned_union
#include <type_traits>
#include <testsuite_tr1.h>
struct MSAlignType { } __attribute__((__aligned__));
template<typename...T>
struct mymax
{
static const std::size_t alignment = 0;
static const std::size_t size = 0;
};
template<typename L, typename...T>
struct mymax<L, T...>
{
static const std::size_t alignment = alignof(L) > mymax<T...>::alignment
? alignof(L) : mymax<T...>::alignment;
static const std::size_t size = sizeof(L) > mymax<T...>::size
? sizeof(L) : mymax<T...>::size;
};
void test01()
{
using std::aligned_union;
using std::alignment_of;
using std::size_t;
using namespace __gnu_test;
const size_t max_a = mymax<char, short, int, double, int[4],
ClassType, MSAlignType>::alignment;
const size_t max_s = mymax<char, short, int, double, int[4],
ClassType, MSAlignType>::size;
typedef aligned_union<0, char, short, int, double, int[4],
ClassType, MSAlignType> au_type;
static_assert(au_type::alignment_value == max_a, "Alignment value");
static_assert(sizeof(au_type::type) >= max_s, "Storage size");
typedef aligned_union<max_s+100, char, short, int, double, int[4],
ClassType, MSAlignType> au_type2;
static_assert(sizeof(au_type2::type) >= max_s+100,
"Storage size (at least len)");
}
int main()
{
test01();
}