1*fdf80e86SSaar Raz // RUN: %clang_cc1 -std=c++2a -fconcepts-ts -x c++ -verify %s 2*fdf80e86SSaar Raz 3*fdf80e86SSaar Raz template<typename T> requires sizeof(T) >= 2 // expected-note{{because 'sizeof(char) >= 2' (1 >= 2) evaluated to false}} 4*fdf80e86SSaar Raz struct A { 5*fdf80e86SSaar Raz static constexpr int value = sizeof(T); 6*fdf80e86SSaar Raz }; 7*fdf80e86SSaar Raz 8*fdf80e86SSaar Raz static_assert(A<int>::value == 4); 9*fdf80e86SSaar Raz static_assert(A<char>::value == 1); // expected-error{{constraints not satisfied for class template 'A' [with T = char]}} 10*fdf80e86SSaar Raz 11*fdf80e86SSaar Raz template<typename T, typename U> 12*fdf80e86SSaar Raz requires sizeof(T) != sizeof(U) // expected-note{{because 'sizeof(int) != sizeof(char [4])' (4 != 4) evaluated to false}} 13*fdf80e86SSaar Raz && sizeof(T) >= 4 // expected-note{{because 'sizeof(char) >= 4' (1 >= 4) evaluated to false}} 14*fdf80e86SSaar Raz constexpr int SizeDiff = sizeof(T) > sizeof(U) ? sizeof(T) - sizeof(U) : sizeof(U) - sizeof(T); 15*fdf80e86SSaar Raz 16*fdf80e86SSaar Raz static_assert(SizeDiff<int, char> == 3); 17*fdf80e86SSaar Raz static_assert(SizeDiff<int, char[4]> == 0); // expected-error{{constraints not satisfied for variable template 'SizeDiff' [with T = int, U = char [4]]}} 18*fdf80e86SSaar Raz static_assert(SizeDiff<char, int> == 3); // expected-error{{constraints not satisfied for variable template 'SizeDiff' [with T = char, U = int]}} 19*fdf80e86SSaar Raz 20*fdf80e86SSaar Raz template<typename... Ts> 21*fdf80e86SSaar Raz requires ((sizeof(Ts) == 4) || ...) // expected-note{{because 'sizeof(char) == 4' (1 == 4) evaluated to false}} expected-note{{'sizeof(long long) == 4' (8 == 4) evaluated to false}} expected-note{{'sizeof(int [20]) == 4' (80 == 4) evaluated to false}} 22*fdf80e86SSaar Raz constexpr auto SumSizes = (sizeof(Ts) + ...); 23*fdf80e86SSaar Raz 24*fdf80e86SSaar Raz static_assert(SumSizes<char, long long, int> == 13); 25*fdf80e86SSaar Raz static_assert(SumSizes<char, long long, int[20]> == 89); // expected-error{{constraints not satisfied for variable template 'SumSizes' [with Ts = <char, long long, int [20]>]}} 26*fdf80e86SSaar Raz 27*fdf80e86SSaar Raz template<typename T> 28*fdf80e86SSaar Raz concept IsBig = sizeof(T) > 100; // expected-note{{because 'sizeof(int) > 100' (4 > 100) evaluated to false}} 29*fdf80e86SSaar Raz 30*fdf80e86SSaar Raz template<typename T> 31*fdf80e86SSaar Raz requires IsBig<T> // expected-note{{'int' does not satisfy 'IsBig'}} 32*fdf80e86SSaar Raz using BigPtr = T*; 33*fdf80e86SSaar Raz 34*fdf80e86SSaar Raz static_assert(sizeof(BigPtr<int>)); // expected-error{{constraints not satisfied for alias template 'BigPtr' [with T = int]}}}} 35*fdf80e86SSaar Raz 36*fdf80e86SSaar Raz template<typename T> requires T::value // expected-note{{because substituted constraint expression is ill-formed: type 'int' cannot be used prior to '::' because it has no members}} 37*fdf80e86SSaar Raz struct S { static constexpr bool value = true; }; 38*fdf80e86SSaar Raz 39*fdf80e86SSaar Raz struct S2 { static constexpr bool value = true; }; 40*fdf80e86SSaar Raz 41*fdf80e86SSaar Raz static_assert(S<int>::value); // expected-error{{constraints not satisfied for class template 'S' [with T = int]}} 42*fdf80e86SSaar Raz static_assert(S<S2>::value); 43*fdf80e86SSaar Raz 44*fdf80e86SSaar Raz template<typename T> 45*fdf80e86SSaar Raz struct AA 46*fdf80e86SSaar Raz { 47*fdf80e86SSaar Raz template<typename U> requires sizeof(U) == sizeof(T) // expected-note{{because 'sizeof(int [2]) == sizeof(int)' (8 == 4) evaluated to false}} 48*fdf80e86SSaar Raz struct B 49*fdf80e86SSaar Raz { 50*fdf80e86SSaar Raz static constexpr int a = 0; 51*fdf80e86SSaar Raz }; 52*fdf80e86SSaar Raz 53*fdf80e86SSaar Raz template<typename U> requires sizeof(U) == sizeof(T) // expected-note{{because 'sizeof(int [2]) == sizeof(int)' (8 == 4) evaluated to false}} 54*fdf80e86SSaar Raz static constexpr int b = 1; 55*fdf80e86SSaar Raz 56*fdf80e86SSaar Raz template<typename U> requires sizeof(U) == sizeof(T) // expected-note{{because 'sizeof(int [2]) == sizeof(int)' (8 == 4) evaluated to false}} 57*fdf80e86SSaar Raz static constexpr int getB() { // expected-note{{candidate template ignored: constraints not satisfied [with U = int [2]]}} 58*fdf80e86SSaar Raz return 2; 59*fdf80e86SSaar Raz } 60*fdf80e86SSaar Raz 61*fdf80e86SSaar Raz static auto foo() 62*fdf80e86SSaar Raz { 63*fdf80e86SSaar Raz return B<T[2]>::a; // expected-error{{constraints not satisfied for class template 'B' [with U = int [2]]}} 64*fdf80e86SSaar Raz } 65*fdf80e86SSaar Raz 66*fdf80e86SSaar Raz static auto foo1() 67*fdf80e86SSaar Raz { 68*fdf80e86SSaar Raz return b<T[2]>; // expected-error{{constraints not satisfied for variable template 'b' [with U = int [2]]}} 69*fdf80e86SSaar Raz } 70*fdf80e86SSaar Raz 71*fdf80e86SSaar Raz static auto foo2() 72*fdf80e86SSaar Raz { 73*fdf80e86SSaar Raz return AA<T>::getB<T[2]>(); // expected-error{{no matching function for call to 'getB'}} 74*fdf80e86SSaar Raz } 75*fdf80e86SSaar Raz }; 76*fdf80e86SSaar Raz 77*fdf80e86SSaar Raz constexpr auto x = AA<int>::foo(); // expected-note{{in instantiation of member function 'AA<int>::foo' requested here}} 78*fdf80e86SSaar Raz constexpr auto x1 = AA<int>::foo1(); // expected-note{{in instantiation of member function 'AA<int>::foo1' requested here}} 79*fdf80e86SSaar Raz constexpr auto x2 = AA<int>::foo2(); // expected-note{{in instantiation of member function 'AA<int>::foo2' requested here}} 80*fdf80e86SSaar Raz 81*fdf80e86SSaar Raz template<typename T> 82*fdf80e86SSaar Raz struct B { using type = typename T::type; }; // expected-error{{type 'int' cannot be used prior to '::' because it has no members}} 83*fdf80e86SSaar Raz 84*fdf80e86SSaar Raz template<typename T> requires B<T>::type // expected-note{{in instantiation of template class 'B<int>' requested here}} 85*fdf80e86SSaar Raz // expected-note@-1{{while substituting template arguments into constraint expression here}} 86*fdf80e86SSaar Raz struct C { }; 87*fdf80e86SSaar Raz 88*fdf80e86SSaar Raz template<typename T> requires T{} // expected-error{{atomic constraint must be of type 'bool' (found 'int')}} 89*fdf80e86SSaar Raz struct D { }; 90*fdf80e86SSaar Raz 91*fdf80e86SSaar Raz static_assert(C<int>{}); // expected-note{{while checking constraint satisfaction for template 'C<int>' required here}} 92*fdf80e86SSaar Raz static_assert(D<int>{}); // expected-note{{while checking constraint satisfaction for template 'D<int>' required here}}