constexpr-value-init.cpp
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// RUN: %clang_cc1 %s -Wno-uninitialized -std=c++11 -fsyntax-only -verify
struct A {
constexpr A() : a(b + 1), b(a + 1) {} // expected-note {{outside its lifetime}}
int a;
int b;
};
struct B {
A a;
};
constexpr A a; // ok, zero initialization precedes static initialization
void f() {
constexpr A a; // expected-error {{constant expression}} expected-note {{in call to 'A()'}}
}
constexpr B b1; // ok
constexpr B b2 = B(); // ok
static_assert(b2.a.a == 1, "");
static_assert(b2.a.b == 2, "");
struct C {
int c;
};
struct D : C { int d; };
constexpr C c1; // expected-error {{without a user-provided default constructor}}
constexpr C c2 = C(); // ok
constexpr D d1; // expected-error {{without a user-provided default constructor}}
constexpr D d2 = D(); // ok with DR1452
static_assert(D().c == 0, "");
static_assert(D().d == 0, "");
struct V : virtual C {};
template<typename T> struct Z : T {
constexpr Z() : V() {}
};
constexpr int n = Z<V>().c; // expected-error {{constant expression}} expected-note {{non-literal type 'Z<V>'}}
struct E {
A a[2];
};
constexpr E e; // ok
static_assert(e.a[0].a == 1, "");
static_assert(e.a[0].b == 2, "");
static_assert(e.a[1].a == 1, "");
static_assert(e.a[1].b == 2, "");