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// RUN: %clang_cc1 -std=c++11 -fsyntax-only -verify %s
namespace std {
typedef decltype(sizeof(int)) size_t;
// libc++'s implementation
template <class _E>
class initializer_list
{
const _E* __begin_;
size_t __size_;
initializer_list(const _E* __b, size_t __s)
: __begin_(__b),
__size_(__s)
{}
public:
typedef _E value_type;
typedef const _E& reference;
typedef const _E& const_reference;
typedef size_t size_type;
typedef const _E* iterator;
typedef const _E* const_iterator;
initializer_list() : __begin_(nullptr), __size_(0) {}
size_t size() const {return __size_;}
const _E* begin() const {return __begin_;}
const _E* end() const {return __begin_ + __size_;}
};
}
struct one { char c[1]; };
struct two { char c[2]; };
struct A {
int a, b;
};
struct B {
B();
B(int, int);
};
void simple_list() {
std::initializer_list<int> il = { 1, 2, 3 };
std::initializer_list<double> dl = { 1.0, 2.0, 3 };
std::initializer_list<A> al = { {1, 2}, {2, 3}, {3, 4} };
std::initializer_list<B> bl = { {1, 2}, {2, 3}, {} };
}
void function_call() {
void f(std::initializer_list<int>);
f({1, 2, 3});
void g(std::initializer_list<B>);
g({ {1, 2}, {2, 3}, {} });
}
struct C {
C(int);
};
struct D {
D();
operator int();
operator C();
};
void overloaded_call() {
one overloaded(std::initializer_list<int>);
two overloaded(std::initializer_list<B>);
static_assert(sizeof(overloaded({1, 2, 3})) == sizeof(one), "bad overload");
static_assert(sizeof(overloaded({ {1, 2}, {2, 3}, {} })) == sizeof(two), "bad overload");
void ambiguous(std::initializer_list<A>); // expected-note {{candidate}}
void ambiguous(std::initializer_list<B>); // expected-note {{candidate}}
ambiguous({ {1, 2}, {2, 3}, {3, 4} }); // expected-error {{ambiguous}}
one ov2(std::initializer_list<int>); // expected-note {{candidate}}
two ov2(std::initializer_list<C>); // expected-note {{candidate}}
// Worst sequence to int is identity, whereas to C it's user-defined.
static_assert(sizeof(ov2({1, 2, 3})) == sizeof(one), "bad overload");
// But here, user-defined is worst in both cases.
ov2({1, 2, D()}); // expected-error {{ambiguous}}
}
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