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// PR c++/44907
struct A { };
struct B
: public A { };
struct C
: public A { };
struct D
: public B, public C { };
template<bool, typename T = void> struct enable_if { typedef T type; };
template<typename T> struct enable_if<false, T> { };
template<typename From, typename To>
class mini_is_convertible
{
typedef char one;
typedef struct { char arr[2]; } two;
template<typename To1>
static void test_aux(To1);
template<typename To1, typename From1>
static typename
enable_if<(sizeof(test_aux<To1>(From1()), 1) > 0), one>::type
test(int);
template<typename, typename>
static two test(...);
public:
static const bool value = sizeof(test<To, From>(0)) == 1;
};
template<typename From, typename To>
const bool mini_is_convertible<From, To>::value;
int Test1[mini_is_convertible<D*, A*>::value ? -1 : 1];
int Test2[mini_is_convertible<A*, D*>::value ? -1 : 1];
int Test3[mini_is_convertible<D, A>::value ? -1 : 1];
int Test4[mini_is_convertible<A, D>::value ? -1 : 1];
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