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// RUN: %clang_cc1 -fexperimental-new-constant-interpreter -verify=expected,both %s
// RUN: %clang_cc1 -verify=ref,both %s
union U {
int a;
int b;
};
constexpr U a = {12};
static_assert(a.a == 12, "");
static_assert(a.b == 0, ""); // both-error {{not an integral constant expression}} \
// both-note {{read of member 'b' of union with active member 'a'}}
union U1 {
int i;
float f = 3.0f;
};
constexpr U1 u1{};
static_assert(u1.f == 3.0, "");
static_assert(u1.i == 1, ""); // both-error {{not an integral constant expression}} \
// both-note {{read of member 'i' of union with active member 'f'}}
union A {
int a;
double d;
};
constexpr A aa = {1, 2.0}; // both-error {{excess elements in union initializer}}
constexpr A ab = {.d = 1.0};
static_assert(ab.d == 1.0, "");
static_assert(ab.a == 1, ""); // both-error {{not an integral constant expression}} \
// both-note {{read of member 'a' of union with active member 'd'}}
namespace Empty {
union E {};
constexpr E e{};
}
namespace SimpleStore {
union A {
int a;
int b;
};
constexpr int foo() {
A a{.b = 4};
a.b = 10;
return a.b;
}
static_assert(foo() == 10, "");
constexpr int empty() {
A a{}; /// Just test that this works.
return 10;
}
static_assert(empty() == 10, "");
}
namespace ZeroInit {
struct S { int m; };
union Z {
float f;
};
constexpr Z z{};
static_assert(z.f == 0.0, "");
}
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