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// Copyright (C) 2016-2018 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/>.
// { dg-do compile { target c++11 } }
// NB: Don't include any other headers in this file.
// LWG 2192 requires <cmath> to declare overloads for integral types.
#include <cmath>
template<typename, typename> struct is_same { enum { value = 0 }; };
template<typename T> struct is_same<T, T> { enum { value = 1 }; };
template<typename T, typename U = T>
constexpr bool check(T val) {
return is_same<decltype(std::abs(val)), U>::value;
}
// Unsigned arguments that promote to int are valid:
static_assert( check<short, int>(1), "abs((short)1) returns int" );
static_assert( check<unsigned short, int>(1),
"abs((unsigned short)1) returns int" );
static_assert( check(1), "abs(1) returns int" );
static_assert( check(1l), "abs(1l) returns long" );
static_assert( check(1ll), "abs(1ll) returns long long" );
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