1 //===----------------------------------------------------------------------===// 2 // 3 // The LLVM Compiler Infrastructure 4 // 5 // This file is dual licensed under the MIT and the University of Illinois Open 6 // Source Licenses. See LICENSE.TXT for details. 7 // 8 //===----------------------------------------------------------------------===// 9 10 // test forward 11 12 #include <utility> 13 #include <cassert> 14 15 #include "test_macros.h" 16 17 struct A 18 { 19 }; 20 21 A source() {return A();} 22 const A csource() {return A();} 23 24 typedef char one; 25 struct two {one _[2];}; 26 struct four {one _[4];}; 27 struct eight {one _[8];}; 28 29 one test(A&); 30 two test(const A&); 31 32 int main() 33 { 34 A a; 35 const A ca = A(); 36 37 ((void)a); // Prevent unused warning 38 ((void)ca); // Prevent unused warning 39 40 #if TEST_STD_VER < 11 41 static_assert(sizeof(test(std::forward<A&>(a))) == 1, ""); 42 static_assert(sizeof(test(std::forward<A>(a))) == 1, ""); 43 44 // Libc++'s C++03 implementation of 'forward' cannot accept true non-const 45 // rvalues. 46 // static_assert(sizeof(test(std::forward<A>(source()))) == 2, ""); 47 48 static_assert(sizeof(test(std::forward<const A&>(a))) == 2, ""); 49 static_assert(sizeof(test(std::forward<const A&>(source()))) == 2, ""); 50 static_assert(sizeof(test(std::forward<const A>(a))) == 2, ""); 51 static_assert(sizeof(test(std::forward<const A>(source()))) == 2, ""); 52 53 static_assert(sizeof(test(std::forward<const A&>(ca))) == 2, ""); 54 static_assert(sizeof(test(std::forward<const A&>(csource()))) == 2, ""); 55 static_assert(sizeof(test(std::forward<const A>(ca))) == 2, ""); 56 static_assert(sizeof(test(std::forward<const A>(csource()))) == 2, ""); 57 #endif 58 } 59
