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 // UNSUPPORTED: c++98, c++03, c++11, c++14 11 // <optional> 12 13 // constexpr T* optional<T>::operator->(); 14 15 #ifdef _LIBCPP_DEBUG 16 #define _LIBCPP_ASSERT(x, m) ((x) ? (void)0 : std::exit(0)) 17 #endif 18 19 #include <optional> 20 #include <type_traits> 21 #include <cassert> 22 23 #include "test_macros.h" 24 25 using std::optional; 26 27 struct X 28 { testX29 int test() noexcept {return 3;} 30 }; 31 32 struct Y 33 { testY34 constexpr int test() {return 3;} 35 }; 36 37 constexpr int test()38test() 39 { 40 optional<Y> opt{Y{}}; 41 return opt->test(); 42 } 43 main()44int main() 45 { 46 { 47 std::optional<X> opt; ((void)opt); 48 ASSERT_SAME_TYPE(decltype(opt.operator->()), X*); 49 // ASSERT_NOT_NOEXCEPT(opt.operator->()); 50 // FIXME: This assertion fails with GCC because it can see that 51 // (A) operator->() is constexpr, and 52 // (B) there is no path through the function that throws. 53 // It's arguable if this is the correct behavior for the noexcept 54 // operator. 55 // Regardless this function should still be noexcept(false) because 56 // it has a narrow contract. 57 } 58 { 59 optional<X> opt(X{}); 60 assert(opt->test() == 3); 61 } 62 { 63 static_assert(test() == 3, ""); 64 } 65 #ifdef _LIBCPP_DEBUG 66 { 67 optional<X> opt; 68 assert(opt->test() == 3); 69 assert(false); 70 } 71 #endif // _LIBCPP_DEBUG 72 } 73