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 // <mutex> 11 12 // struct once_flag; 13 14 // constexpr once_flag() noexcept; 15 16 #include <mutex> 17 18 int main() 19 { 20 { 21 std::once_flag f; 22 } 23 #ifndef _LIBCPP_HAS_NO_CONSTEXPR 24 { 25 constexpr std::once_flag f; 26 } 27 #endif 28 } 29
