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// RUN: %clang_cc1 -std=c++2a -verify %s
struct S2 {};
// expected-note@-1 {{candidate constructor (the implicit copy constructor) not viable: no known conversion from 'S1' to 'const S2' for 1st argument}}
// expected-note@-2 {{candidate constructor (the implicit move constructor) not viable: no known conversion from 'S1' to 'S2' for 1st argument}}
// expected-note@-3 {{candidate constructor (the implicit default constructor) not viable: requires 0 arguments, but 1 was provided}}
struct S1 {
void foo() const requires true {}
void foo() const requires false {}
void bar() const requires false {}
// expected-note@-1 {{because 'false' evaluated to false}}
operator bool() const requires true { return true; }
explicit operator bool() const requires false;
explicit operator S2() const requires false;
// expected-note@-1 {{candidate function not viable: constraints not satisfied}}
// expected-note@-2 {{because 'false' evaluated to false}}
};
void foo() {
S1().foo();
S1().bar();
// expected-error@-1 {{invalid reference to function 'bar': constraints not satisfied}}
(void) static_cast<bool>(S1());
(void) static_cast<S2>(S1());
// expected-error@-1 {{no matching conversion for static_cast from 'S1' to 'S2'}}
}
// Test that constraints are checked before implicit conversions are formed.
template<typename T>
struct invalid_template { using X = typename T::non_existant; };
struct A {
template<typename T, bool=invalid_template<T>::aadasas>
operator T() {}
};
void foo(int) requires false;
void foo(A) requires true;
struct S {
void foo(int) requires false;
void foo(A) requires true;
S(A) requires false;
S(double) requires true;
~S() requires false;
// expected-note@-1 2{{because 'false' evaluated to false}}
~S() requires true;
operator int() requires true;
operator int() requires false;
};
void bar() {
foo(A{});
S{1.}.foo(A{});
// expected-error@-1{{invalid reference to function '~S': constraints not satisfied}}
// Note - this behavior w.r.t. constrained dtors is a consequence of current
// wording, which does not invoke overload resolution when a dtor is called.
// P0848 is set to address this issue.
S s = 1;
// expected-error@-1{{invalid reference to function '~S': constraints not satisfied}}
int a = s;
}
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