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 const T* optional<T>::operator->() const; 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 { 29 constexpr int test() const {return 3;} 30 }; 31 32 struct Y 33 { 34 int test() const noexcept {return 2;} 35 }; 36 37 struct Z 38 { 39 const Z* operator&() const; 40 constexpr int test() const {return 1;} 41 }; 42 43 int main() 44 { 45 { 46 const std::optional<X> opt; ((void)opt); 47 ASSERT_SAME_TYPE(decltype(opt.operator->()), X const*); 48 // ASSERT_NOT_NOEXCEPT(opt.operator->()); 49 // FIXME: This assertion fails with GCC because it can see that 50 // (A) operator->() is constexpr, and 51 // (B) there is no path through the function that throws. 52 // It's arguable if this is the correct behavior for the noexcept 53 // operator. 54 // Regardless this function should still be noexcept(false) because 55 // it has a narrow contract. 56 } 57 { 58 constexpr optional<X> opt(X{}); 59 static_assert(opt->test() == 3, ""); 60 } 61 { 62 constexpr optional<Y> opt(Y{}); 63 assert(opt->test() == 2); 64 } 65 { 66 constexpr optional<Z> opt(Z{}); 67 static_assert(opt->test() == 1, ""); 68 } 69 #ifdef _LIBCPP_DEBUG 70 { 71 const optional<X> opt; 72 assert(opt->test() == 3); 73 assert(false); 74 } 75 #endif // _LIBCPP_DEBUG 76 } 77
