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// RUN: %clang_cc1 -std=c++98 %s -verify -fexceptions -fcxx-exceptions -pedantic-errors
// RUN: %clang_cc1 -std=c++11 %s -verify -fexceptions -fcxx-exceptions -pedantic-errors
// RUN: %clang_cc1 -std=c++14 %s -verify -fexceptions -fcxx-exceptions -pedantic-errors
// RUN: %clang_cc1 -std=c++1z %s -verify -fexceptions -fcxx-exceptions -pedantic-errors
#if __cplusplus < 201103L
// expected-no-diagnostics
#endif
namespace dr1460 { // dr1460: 3.5
#if __cplusplus >= 201103L
namespace DRExample {
union A {
union {};
union {};
constexpr A() {}
};
constexpr A a = A();
union B {
union {};
union {};
constexpr B() = default;
};
constexpr B b = B();
union C {
union {};
union {};
};
constexpr C c = C();
#if __cplusplus > 201103L
constexpr void f() { C c; }
static_assert((f(), true), "");
#endif
}
union A {};
union B { int n; }; // expected-note +{{here}}
union C { int n = 0; };
struct D { union {}; };
struct E { union { int n; }; }; // expected-note +{{here}}
struct F { union { int n = 0; }; };
struct X {
friend constexpr A::A() noexcept;
friend constexpr B::B() noexcept; // expected-error {{follows non-constexpr declaration}}
friend constexpr C::C() noexcept;
friend constexpr D::D() noexcept;
friend constexpr E::E() noexcept; // expected-error {{follows non-constexpr declaration}}
friend constexpr F::F() noexcept;
};
// These are OK, because value-initialization doesn't actually invoke the
// constructor.
constexpr A a = A();
constexpr B b = B();
constexpr C c = C();
constexpr D d = D();
constexpr E e = E();
constexpr F f = F();
namespace Defaulted {
union A { constexpr A() = default; };
union B { int n; constexpr B() = default; }; // expected-error {{not constexpr}}
union C { int n = 0; constexpr C() = default; };
struct D { union {}; constexpr D() = default; };
struct E { union { int n; }; constexpr E() = default; }; // expected-error {{not constexpr}}
struct F { union { int n = 0; }; constexpr F() = default; };
struct G { union { int n = 0; }; union { int m; }; constexpr G() = default; }; // expected-error {{not constexpr}}
struct H {
union {
int n = 0;
};
union { // expected-note 2{{member not initialized}}
int m;
};
constexpr H() {} // expected-error {{must initialize all members}}
constexpr H(bool) : m(1) {}
constexpr H(char) : n(1) {} // expected-error {{must initialize all members}}
constexpr H(double) : m(1), n(1) {}
};
}
#if __cplusplus > 201103L
template<typename T> constexpr bool check() {
T t; // expected-note-re 2{{non-constexpr constructor '{{[BE]}}'}}
return true;
}
static_assert(check<A>(), "");
static_assert(check<B>(), ""); // expected-error {{constant}} expected-note {{in call}}
static_assert(check<C>(), "");
static_assert(check<D>(), "");
static_assert(check<E>(), ""); // expected-error {{constant}} expected-note {{in call}}
static_assert(check<F>(), "");
#endif
union G {
int a = 0; // expected-note {{previous initialization is here}}
int b = 0; // expected-error {{initializing multiple members of union}}
};
union H {
union {
int a = 0; // expected-note {{previous initialization is here}}
};
union {
int b = 0; // expected-error {{initializing multiple members of union}}
};
};
struct I {
union {
int a = 0; // expected-note {{previous initialization is here}}
int b = 0; // expected-error {{initializing multiple members of union}}
};
};
struct J {
union { int a = 0; };
union { int b = 0; };
};
namespace Overriding {
struct A {
int a = 1, b, c = 3;
constexpr A() : b(2) {}
};
static_assert(A().a == 1 && A().b == 2 && A().c == 3, "");
union B {
int a, b = 2, c;
constexpr B() : a(1) {}
constexpr B(char) : b(4) {}
constexpr B(int) : c(3) {}
constexpr B(const char*) {}
};
static_assert(B().a == 1, "");
static_assert(B().b == 2, ""); // expected-error {{constant}} expected-note {{read of}}
static_assert(B('x').a == 0, ""); // expected-error {{constant}} expected-note {{read of}}
static_assert(B('x').b == 4, "");
static_assert(B(123).b == 2, ""); // expected-error {{constant}} expected-note {{read of}}
static_assert(B(123).c == 3, "");
static_assert(B("").a == 1, ""); // expected-error {{constant}} expected-note {{read of}}
static_assert(B("").b == 2, "");
static_assert(B("").c == 3, ""); // expected-error {{constant}} expected-note {{read of}}
struct C {
union { int a, b = 2, c; };
union { int d, e = 5, f; };
constexpr C() : a(1) {}
constexpr C(char) : c(3) {}
constexpr C(int) : d(4) {}
constexpr C(float) : f(6) {}
constexpr C(const char*) {}
};
static_assert(C().a == 1, "");
static_assert(C().b == 2, ""); // expected-error {{constant}} expected-note {{read of}}
static_assert(C().d == 4, ""); // expected-error {{constant}} expected-note {{read of}}
static_assert(C().e == 5, "");
static_assert(C('x').b == 2, ""); // expected-error {{constant}} expected-note {{read of}}
static_assert(C('x').c == 3, "");
static_assert(C('x').d == 4, ""); // expected-error {{constant}} expected-note {{read of}}
static_assert(C('x').e == 5, "");
static_assert(C(1).b == 2, "");
static_assert(C(1).c == 3, ""); // expected-error {{constant}} expected-note {{read of}}
static_assert(C(1).d == 4, "");
static_assert(C(1).e == 5, ""); // expected-error {{constant}} expected-note {{read of}}
static_assert(C(1.f).b == 2, "");
static_assert(C(1.f).c == 3, ""); // expected-error {{constant}} expected-note {{read of}}
static_assert(C(1.f).e == 5, ""); // expected-error {{constant}} expected-note {{read of}}
static_assert(C(1.f).f == 6, "");
static_assert(C("").a == 1, ""); // expected-error {{constant}} expected-note {{read of}}
static_assert(C("").b == 2, "");
static_assert(C("").c == 3, ""); // expected-error {{constant}} expected-note {{read of}}
static_assert(C("").d == 4, ""); // expected-error {{constant}} expected-note {{read of}}
static_assert(C("").e == 5, "");
static_assert(C("").f == 6, ""); // expected-error {{constant}} expected-note {{read of}}
struct D;
extern const D d;
struct D {
int a;
union {
int b = const_cast<D&>(d).a = 1; // not evaluated
int c;
};
constexpr D() : a(0), c(0) {}
};
constexpr D d {};
static_assert(d.a == 0, "");
}
#endif
}
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