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// RUN: %clang_cc1 -std=c++11 -fsyntax-only -verify %s
struct non_trivial {
non_trivial();
non_trivial(const non_trivial&);
non_trivial& operator = (const non_trivial&);
~non_trivial();
};
union u {
non_trivial nt;
};
union u2 {
non_trivial nt;
int k;
u2(int k) : k(k) {}
u2() : nt() {}
};
union static_data_member {
static int i;
};
int static_data_member::i;
union bad {
int &i; // expected-error {{union member 'i' has reference type 'int &'}}
};
struct s {
union {
non_trivial nt;
};
};
// Don't crash on this.
struct TemplateCtor { template<typename T> TemplateCtor(T); };
union TemplateCtorMember { TemplateCtor s; };
template<typename T> struct remove_ref { typedef T type; };
template<typename T> struct remove_ref<T&> { typedef T type; };
template<typename T> struct remove_ref<T&&> { typedef T type; };
template<typename T> T &&forward(typename remove_ref<T>::type &&t);
template<typename T> T &&forward(typename remove_ref<T>::type &t);
template<typename T> typename remove_ref<T>::type &&move(T &&t);
using size_t = decltype(sizeof(int));
void *operator new(size_t, void *p) noexcept { return p; }
namespace disabled_dtor {
template<typename T>
union disable_dtor {
T val;
template<typename...U>
disable_dtor(U &&...u) : val(forward<U>(u)...) {}
~disable_dtor() {}
};
struct deleted_dtor {
deleted_dtor(int n, char c) : n(n), c(c) {}
int n;
char c;
~deleted_dtor() = delete;
};
disable_dtor<deleted_dtor> dd(4, 'x');
}
namespace optional {
template<typename T> struct optional {
bool has;
union { T value; };
optional() : has(false) {}
template<typename...U>
optional(U &&...u) : has(true), value(forward<U>(u)...) {}
optional(const optional &o) : has(o.has) {
if (has) new (&value) T(o.value);
}
optional(optional &&o) : has(o.has) {
if (has) new (&value) T(move(o.value));
}
optional &operator=(const optional &o) {
if (has) {
if (o.has)
value = o.value;
else
value.~T();
} else if (o.has) {
new (&value) T(o.value);
}
has = o.has;
}
optional &operator=(optional &&o) {
if (has) {
if (o.has)
value = move(o.value);
else
value.~T();
} else if (o.has) {
new (&value) T(move(o.value));
}
has = o.has;
}
~optional() {
if (has)
value.~T();
}
explicit operator bool() const { return has; }
T &operator*() { return value; }
};
optional<non_trivial> o1;
optional<non_trivial> o2{non_trivial()};
optional<non_trivial> o3{*o2};
void f() {
if (o2)
o1 = o2;
o2 = optional<non_trivial>();
}
}
namespace pr16061 {
struct X { X(); };
template<typename T> struct Test1 {
union {
struct {
X x;
};
};
};
template<typename T> struct Test2 {
union {
struct { // expected-note-re {{default constructor of 'Test2<pr16061::X>' is implicitly deleted because variant field 'struct (anonymous struct at{{.+}})' has a non-trivial default constructor}}
T x;
};
};
};
Test2<X> t2x; // expected-error {{call to implicitly-deleted default constructor of 'Test2<X>'}}
}
namespace GH48416 {
struct non_trivial_constructor {
constexpr non_trivial_constructor() : x(100) {}
int x;
};
union U1 {
int a;
non_trivial_constructor b; // expected-note {{has a non-trivial default constructor}}
};
union U2 {
int a{1000};
non_trivial_constructor b;
};
union U3 {
int a;
non_trivial_constructor b{};
};
union U4 {
int a{}; // expected-note {{previous initialization is here}}
non_trivial_constructor b{}; // expected-error {{initializing multiple members of union}}
};
U1 u1; // expected-error {{call to implicitly-deleted default constructor}}
U2 u2;
U3 u3;
U4 u4;
static_assert(U2().a == 1000, "");
static_assert(U3().a == 1000, "");
// expected-error@-1 {{static assertion expression is not an integral constant expression}}
// expected-note@-2 {{read of member 'a' of union with active member 'b'}}
static_assert(U2().b.x == 100, "");
// expected-error@-1 {{static assertion expression is not an integral constant expression}}
// expected-note@-2 {{read of member 'b' of union with active member 'a'}}
static_assert(U3().b.x == 100, "");
} // namespace GH48416
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