llvm-project/clang/test/SemaTemplate/alias-templates.cpp

247 lines
7.3 KiB
C++

// RUN: %clang_cc1 -std=c++11 -fsyntax-only -verify %s
template<typename S>
struct A {
typedef S B;
template<typename T> using C = typename T::B;
template<typename T> struct D {
template<typename U> using E = typename A<U>::template C<A<T>>;
template<typename U> using F = A<E<U>>;
template<typename U> using G = C<F<U>>;
G<T> g;
};
typedef decltype(D<B>().g) H;
D<H> h;
template<typename T> using I = A<decltype(h.g)>;
template<typename T> using J = typename A<decltype(h.g)>::template C<I<T>>;
};
A<int> a;
A<char>::D<double> b;
template<typename T> T make();
namespace X {
template<typename T> struct traits {
typedef T thing;
typedef decltype(val(make<thing>())) inner_ptr;
template<typename U> using rebind_thing = typename thing::template rebind<U>;
template<typename U> using rebind = traits<rebind_thing<U>>;
inner_ptr &&alloc();
void free(inner_ptr&&);
};
template<typename T> struct ptr_traits {
typedef T *type;
};
template<typename T> using ptr = typename ptr_traits<T>::type;
template<typename T> struct thing {
typedef T inner;
typedef ptr<inner> inner_ptr;
typedef traits<thing<inner>> traits_type;
template<typename U> using rebind = thing<U>;
thing(traits_type &traits) : traits(traits), val(traits.alloc()) {}
~thing() { traits.free(static_cast<inner_ptr&&>(val)); }
traits_type &traits;
inner_ptr val;
friend inner_ptr val(const thing &t) { return t.val; }
};
template<> struct ptr_traits<bool> {
typedef bool &type;
};
template<> bool &traits<thing<bool>>::alloc() { static bool b; return b; }
template<> void traits<thing<bool>>::free(bool&) {}
}
typedef X::traits<X::thing<int>> itt;
itt::thing::traits_type itr;
itt::thing ith(itr);
itt::rebind<bool> btr;
itt::rebind_thing<bool> btt(btr);
namespace PR11848 {
template<typename T> using U = int;
template<typename T, typename ...Ts>
void f1(U<T> i, U<Ts> ...is) { // expected-note 2{{couldn't infer template argument 'T'}}
return i + f1<Ts...>(is...);
}
// FIXME: This note is technically correct, but could be better. We
// should really say that we couldn't infer template argument 'Ts'.
template<typename ...Ts>
void f2(U<Ts> ...is) { } // expected-note {{requires 0 arguments, but 1 was provided}}
template<typename...> struct type_tuple {};
template<typename ...Ts>
void f3(type_tuple<Ts...>, U<Ts> ...is) {} // expected-note {{requires 4 arguments, but 3 were provided}}
void g() {
f1(U<void>()); // expected-error {{no match}}
f1(1, 2, 3, 4, 5); // expected-error {{no match}}
f2(); // ok
f2(1); // expected-error {{no match}}
f3(type_tuple<>());
f3(type_tuple<void, void, void>(), 1, 2); // expected-error {{no match}}
f3(type_tuple<void, void, void>(), 1, 2, 3);
}
template<typename ...Ts>
struct S {
S(U<Ts>...ts);
};
template<typename T>
struct Hidden1 {
template<typename ...Ts>
Hidden1(typename T::template U<Ts> ...ts);
};
template<typename T, typename ...Ts>
struct Hidden2 {
Hidden2(typename T::template U<Ts> ...ts);
};
struct Hide {
template<typename T> using U = int;
};
Hidden1<Hide> h1;
Hidden2<Hide, double, char> h2(1, 2);
}
namespace Core22036 {
struct X {};
void h(...);
template<typename T> using Y = X;
template<typename T, typename ...Ts> struct S {
// An expression can contain an unexpanded pack without being type or
// value dependent. This is true even if the expression's type is a pack
// expansion type.
void f1(Y<T> a) { h(g(a)); } // expected-error {{undeclared identifier 'g'}}
void f2(Y<Ts>...as) { h(g(as)...); } // expected-error {{undeclared identifier 'g'}}
void f3(Y<Ts>...as) { g(as...); } // ok
void f4(Ts ...ts) { h(g(sizeof(ts))...); } // expected-error {{undeclared identifier 'g'}}
// FIXME: We can reject this, since it has no valid instantiations because
// 'g' never has any associated namespaces.
void f5(Ts ...ts) { g(sizeof(ts)...); } // ok
};
}
namespace PR13243 {
template<typename A> struct X {};
template<int I> struct C {};
template<int I> using Ci = C<I>;
template<typename A, int I> void f(X<A>, Ci<I>) {}
template void f(X<int>, C<0>);
}
namespace PR13136 {
template <typename T, T... Numbers>
struct NumberTuple { };
template <unsigned int... Numbers>
using MyNumberTuple = NumberTuple<unsigned int, Numbers...>;
template <typename U, unsigned int... Numbers>
void foo(U&&, MyNumberTuple<Numbers...>);
template <typename U, unsigned int... Numbers>
void bar(U&&, NumberTuple<unsigned int, Numbers...>);
int main() {
foo(1, NumberTuple<unsigned int, 0, 1>());
bar(1, NumberTuple<unsigned int, 0, 1>());
return 0;
}
}
namespace PR16646 {
namespace test1 {
template <typename T> struct DefaultValue { const T value=0;};
template <typename ... Args> struct tuple {};
template <typename ... Args> using Zero = tuple<DefaultValue<Args> ...>;
template <typename ... Args> void f(const Zero<Args ...> &t);
void f() {
f(Zero<int,double,double>());
}
}
namespace test2 {
template<int x> struct X {};
template <template<int x> class temp> struct DefaultValue { const temp<0> value; };
template <typename ... Args> struct tuple {};
template <template<int x> class... Args> using Zero = tuple<DefaultValue<Args> ...>;
template <template<int x> class... Args> void f(const Zero<Args ...> &t);
void f() {
f(Zero<X,X,X>());
}
}
}
namespace PR16904 {
template <typename,typename>
struct base {
template <typename> struct derived;
};
// FIXME: The diagnostics here are terrible.
template <typename T, typename U, typename V>
using derived = base<T, U>::template derived<V>; // expected-error {{expected a type}} expected-error {{expected ';'}}
template <typename T, typename U, typename V>
using derived2 = ::PR16904::base<T, U>::template derived<V>; // expected-error {{expected a type}} expected-error {{expected ';'}}
}
namespace PR14858 {
template<typename ...T> using X = int[sizeof...(T)];
template<typename ...U> struct Y {
using Z = X<U...>;
};
using A = Y<int, int, int, int>::Z;
using A = int[4];
// FIXME: These should be treated as being redeclarations.
template<typename ...T> void f(X<T...> &) {}
template<typename ...T> void f(int(&)[sizeof...(T)]) {}
template<typename ...T> void g(X<typename T::type...> &) {}
template<typename ...T> void g(int(&)[sizeof...(T)]) {} // ok, different
template<typename ...T, typename ...U> void h(X<T...> &) {}
template<typename ...T, typename ...U> void h(X<U...> &) {} // ok, different
template<typename ...T> void i(auto (T ...t) -> int(&)[sizeof...(t)]);
auto mk_arr(int, int) -> int(&)[2];
void test_i() { i<int, int>(mk_arr); }
#if 0 // FIXME: This causes clang to assert.
template<typename ...T> using Z = auto (T ...p) -> int (&)[sizeof...(p)];
template<typename ...T, typename ...U> void j(Z<T..., U...> &) {}
void test_j() { j<int, int>(mk_arr); }
#endif
template<typename ...T> struct Q {
template<typename ...U> using V = int[sizeof...(U)];
template<typename ...U> void f(V<typename U::type..., typename T::type...> *);
};
struct B { typedef int type; };
void test_q(int (&a)[5]) { Q<B, B, B>().f<B, B>(&a); }
}
namespace redecl {
template<typename> using A = int;
template<typename = void> using A = int;
A<> a; // ok
}