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// RUN: %clang_cc1 -std=c++11 -verify %s
struct B1 {
B1(int); // expected-note {{candidate}}
};
struct B2 {
B2(int); // expected-note {{candidate}}
};
struct D1 : B1, B2 {
using B1::B1; // expected-note {{inherited here}}
using B2::B2; // expected-note {{inherited here}}
};
D1 d1(0); // expected-error {{ambiguous}}
struct D2 : B1, B2 {
using B1::B1;
using B2::B2;
D2(int);
};
D2 d2(0); // ok
// The emergent behavior of implicit special members is a bit odd when
// inheriting from multiple base classes.
namespace default_ctor {
struct C;
struct D;
struct convert_to_D1 {
operator D&&();
};
struct convert_to_D2 {
operator D&&();
};
struct A {
A();
A(C &&);
C &operator=(C&&);
A(D &&);
D &operator=(D&&); // expected-note {{candidate}}
A(convert_to_D2); // expected-note {{candidate}}
};
struct B {
B();
B(C &&);
C &operator=(C&&);
B(D &&);
D &operator=(D&&); // expected-note {{candidate}}
B(convert_to_D2); // expected-note {{candidate}}
};
struct C : A, B {
using A::A;
using A::operator=;
using B::B;
using B::operator=;
};
struct D : A, B {
using A::A; // expected-note {{inherited here}}
using A::operator=;
using B::B; // expected-note {{inherited here}}
using B::operator=;
D(int);
D(const D&);
D &operator=(const D&);
};
C c;
void f(C c) {
C c2(static_cast<C&&>(c));
c = static_cast<C&&>(c);
}
// D does not declare D(), D(D&&), nor operator=(D&&), so the base class
// versions are inherited.
// Exception: we implicitly declare a default constructor so that we can
// reason about its properties.
D d; // ok, implicitly declared
void f(D d) {
D d2(static_cast<D&&>(d)); // ok, ignores inherited constructors
D d3(convert_to_D1{}); // ok, ignores inherited constructors
D d4(convert_to_D2{}); // expected-error {{ambiguous}}
d = static_cast<D&&>(d); // expected-error {{ambiguous}}
}
struct Y;
struct X {
X();
X(volatile Y &); // expected-note 3{{inherited constructor cannot be used to copy object}}
} x;
struct Y : X { using X::X; } volatile y;
struct Z : Y { using Y::Y; } volatile z; // expected-note 4{{no known conversion}} expected-note 2{{would lose volatile}} expected-note 3{{requires 0}} expected-note 3{{inherited here}}
Z z1(x); // expected-error {{no match}}
Z z2(y); // expected-error {{no match}}
Z z3(z); // expected-error {{no match}}
}
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