1 //===----------------------------------------------------------------------===// 2 // 3 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions. 4 // See https://llvm.org/LICENSE.txt for license information. 5 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception 6 // 7 //===----------------------------------------------------------------------===// 8 9 // UNSUPPORTED: c++98, c++03, c++11 10 11 // <functional> 12 13 // Hashing a struct w/o a defined hash should *not* fail, but it should 14 // create a type that is not constructible and not callable. 15 // See also: https://cplusplus.github.io/LWG/lwg-defects.html#2543 16 17 #include <functional> 18 #include <cassert> 19 #include <type_traits> 20 21 #include "test_macros.h" 22 23 struct X {}; 24 25 int main() 26 { 27 using H = std::hash<X>; 28 static_assert(!std::is_default_constructible<H>::value, ""); 29 static_assert(!std::is_copy_constructible<H>::value, ""); 30 static_assert(!std::is_move_constructible<H>::value, ""); 31 static_assert(!std::is_copy_assignable<H>::value, ""); 32 static_assert(!std::is_move_assignable<H>::value, ""); 33 #if TEST_STD_VER > 14 34 static_assert(!std::is_invocable<H, X&>::value, ""); 35 static_assert(!std::is_invocable<H, X const&>::value, ""); 36 #endif 37 } 38