|  | // Copyright (C) 2016-2021 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/>. | 
|  |  | 
|  | // { dg-do compile { target c++11 } } | 
|  |  | 
|  | #include <cmath> | 
|  | // Also make names from <cmath> available in the global namespace: | 
|  | #include <math.h> | 
|  |  | 
|  | bool foo(double d) | 
|  | { | 
|  | return ::isfinite(d); // PR libstdc++/14608 | 
|  | } | 
|  |  | 
|  | int bar(double d) | 
|  | { | 
|  | return ::signbit(d); // PR libstdc++/44611 | 
|  | } | 
|  |  | 
|  | constexpr bool is_double(double) { return true; } | 
|  | template<typename T> constexpr bool is_double(T) { return false; } | 
|  | using type = decltype(::abs(1.5)); | 
|  | static_assert(is_double(type{}), "::abs(double) overload exists in <math.h>"); |