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// RUN: %clang_cc1 -std=c++11 %s -verify
namespace PR15757 {
struct S {
};
template<typename X, typename Y> struct T {
template<typename A> T(X x, A &&a) {}
template<typename A> explicit T(A &&a)
noexcept(noexcept(T(X(), static_cast<A &&>(a))))
: T(X(), static_cast<A &&>(a)) {}
};
template<typename X, typename Y> struct U : T<X, Y> {
using T<X, Y>::T;
};
U<S, char> foo(char ch) { return U<S, char>(ch); }
int main() {
U<S, int> a(42);
U<S, char> b('4');
return 0;
}
}
namespace WrongIdent {
struct A {};
struct B : A {};
struct C : B {
using B::A;
};
}
namespace DefaultCtorConflict {
struct A { A(int = 0); };
struct B : A {
using A::A;
} b; // ok, not ambiguous, inherited constructor suppresses implicit default constructor
struct C {
B b;
} c;
}
namespace InvalidConstruction {
struct A { A(int); };
struct B { B() = delete; };
struct C : A, B { using A::A; };
// Initialization here is performed as if by a defaulted default constructor,
// which would be ill-formed (in the immediate context) in this case because
// it would be defined as deleted.
template<typename T> void f(decltype(T(0))*);
template<typename T> int &f(...);
int &r = f<C>(0);
}
namespace ExplicitConv {
struct B {};
struct D : B { // expected-note 3{{candidate}}
using B::B;
};
struct X { explicit operator B(); } x;
struct Y { explicit operator D(); } y;
D dx(x); // expected-error {{no matching constructor}}
D dy(y);
}
namespace NestedListInit {
struct B { B(); } b; // expected-note 3{{candidate}}
struct D : B { // expected-note 14{{not viable}}
using B::B;
};
// This is a bit weird. We're allowed one pair of braces for overload
// resolution, and one more pair of braces due to [over.ics.list]/2.
B b1 = {b};
B b2 = {{b}};
B b3 = {{{b}}}; // expected-error {{no match}}
// Per a proposed defect resolution, we don't get to call
// D's version of B::B(const B&) here.
D d0 = b; // expected-error {{no viable conversion}}
D d1 = {b}; // expected-error {{no match}}
D d2 = {{b}}; // expected-error {{no match}}
D d3 = {{{b}}}; // expected-error {{no match}}
D d4 = {{{{b}}}}; // expected-error {{no match}}
}
namespace PR31606 {
// PR31606: as part of a proposed defect resolution, do not consider
// inherited constructors that would be copy constructors for any class
// between the declaring class and the constructed class (inclusive).
struct Base {};
struct A : Base {
using Base::Base;
bool operator==(A const &) const; // expected-note {{no known conversion from 'PR31606::B' to 'const PR31606::A' for 1st argument}}
};
struct B : Base {
using Base::Base;
};
bool a = A{} == A{};
// Note, we do *not* allow operator=='s argument to use the inherited A::A(Base&&) constructor to construct from B{}.
bool b = A{} == B{}; // expected-error {{invalid operands}}
}
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