argument-dependent-lookup.cpp
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// RUN: %clang_cc1 -std=c++14 -verify %s
// RUN: %clang_cc1 -std=c++14 -verify %s -DHAVE_UNQUALIFIED_LOOKUP_RESULTS
// expected-no-diagnostics
namespace address_of {
#ifdef HAVE_UNQUALIFIED_LOOKUP_RESULTS
struct Q {};
void operator&(Q);
#endif
template<typename T> struct A {
static constexpr auto x = &T::value;
};
template<typename T> struct B {
constexpr int operator&() { return 123; }
};
template<typename T> struct C {
static_assert(sizeof(T) == 123, "");
};
struct X1 {
static B<X1> value;
};
struct X2 : B<X2> {
enum E { value };
friend constexpr int operator&(E) { return 123; }
};
struct Y1 {
C<int> *value;
};
struct Y2 {
C<int> value();
};
// ok, uses ADL to find operator&:
static_assert(A<X1>::x == 123, "");
static_assert(A<X2>::x == 123, "");
// ok, does not use ADL so does not instantiate C<T>:
static_assert(A<Y1>::x == &Y1::value, "");
static_assert(A<Y2>::x == &Y2::value, "");
}