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// RUN: %clang_cc1 -std=c++17 -verify=expected,cxx17 %s
// RUN: %clang_cc1 -std=c++20 -verify=expected,cxx20 %s
namespace pr41427 {
template <typename T> class A {
public:
A(void (*)(T)) {}
};
void D(int) {}
void f() {
A a(&D);
using T = decltype(a);
using T = A<int>;
}
}
namespace Access {
struct B {
protected:
struct type {};
};
template<typename T> struct D : B { // expected-note {{not viable}} \
expected-note {{implicit deduction guide declared as 'template <typename T> D(Access::D<T>) -> Access::D<T>'}}
D(T, typename T::type); // expected-note {{private member}} \
// expected-note {{implicit deduction guide declared as 'template <typename T> D(T, typename T::type) -> Access::D<T>'}}
};
D b = {B(), {}};
class X {
using type = int;
};
D x = {X(), {}}; // expected-error {{no viable constructor or deduction guide}}
// Once we implement proper support for dependent nested name specifiers in
// friends, this should still work.
class Y {
template <typename T> friend D<T>::D(T, typename T::type); // expected-warning {{dependent nested name specifier}}
struct type {};
};
D y = {Y(), {}};
class Z {
template <typename T> friend class D;
struct type {};
};
D z = {Z(), {}};
}
namespace GH69987 {
template<class> struct X {};
template<class = void> struct X;
X x;
template<class T, class B> struct Y { Y(T); };
template<class T, class B=void> struct Y ;
Y y(1);
}
namespace NoCrashOnGettingDefaultArgLoc {
template <typename>
class A {
A(int = 1); // expected-note {{candidate template ignored: couldn't infer template argumen}} \
// expected-note {{implicit deduction guide declared as 'template <typename> D(int = <null expr>) -> NoCrashOnGettingDefaultArgLoc::D<type-parameter-0-0>'}}
};
class C : A<int> {
using A::A;
};
template <typename>
class D : C { // expected-note {{candidate function template not viable: requires 1 argument}} \
expected-note {{implicit deduction guide declared as 'template <typename> D(NoCrashOnGettingDefaultArgLoc::D<type-parameter-0-0>) -> NoCrashOnGettingDefaultArgLoc::D<type-parameter-0-0>'}}
using C::C;
};
D abc; // expected-error {{no viable constructor or deduction guide}}
}
namespace AsValueParameter {
namespace foo {
// cxx17-note@+2 {{template is declared here}}
// cxx20-note@+1 {{'A<int>' is not literal because it is not an aggregate and has no constexpr constructors other than copy or move constructors}}
template <class> struct A {
A();
};
}
template <foo::A> struct B {}; // expected-note {{template parameter is declared here}}
// cxx17-error@-1 {{use of class template 'foo::A' requires template arguments; argument deduction not allowed in template parameter}}
template struct B<foo::A<int>{}>;
// cxx17-error@-1 {{value of type 'foo::A<int>' is not implicitly convertible to 'int'}}
// cxx20-error@-2 {{non-type template parameter has non-literal type 'foo::A<int>' (aka 'AsValueParameter::foo::A<int>')}}
} // namespace AsValueParameter
namespace ConvertDeducedTemplateArgument {
namespace A {
template <class> struct B {};
}
template <template <class> class TT1> struct C {
C(TT1<int>);
};
template <template <class> class TT2> using D = TT2<int>;
auto x = C(D<A::B>());
}
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