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// I, Howard Hinnant, hereby place this code in the public domain.
// Test the "Augmented" template argument deduction when binding an lvalue to an rvalue reference.
// { dg-do compile { target c++11 } }
template <bool> struct sa;
template <> struct sa<true> {};
template <class T, T v>
struct integral_constant
{
static const T value = v;
typedef T value_type;
typedef integral_constant<T, v> type;
};
typedef integral_constant<bool, true> true_type;
typedef integral_constant<bool, false> false_type;
template <class T> struct is_lvalue_reference : public integral_constant<bool, false> {};
template <class T> struct is_lvalue_reference<T&> : public integral_constant<bool, true> {};
template <class T> struct is_rvalue_reference : public integral_constant<bool, false> {};
template <class T> struct is_rvalue_reference<T&&> : public integral_constant<bool, true> {};
template <bool is_lvalue_ref, bool is_rvalue_ref, class T>
void
test1(T&&)
{
sa<is_lvalue_reference<T&&>::value == is_lvalue_ref> t1;
sa<is_rvalue_reference<T&&>::value == is_rvalue_ref> t2;
}
template <bool is_lvalue_ref, bool is_rvalue_ref, class T>
void
test2(const T&&) // { dg-message "argument" }
{
sa<is_lvalue_reference<const T&&>::value == is_lvalue_ref> t1;
sa<is_rvalue_reference<const T&&>::value == is_rvalue_ref> t2;
}
template <bool is_lvalue_ref, bool is_rvalue_ref, class T>
void
test3(T*&&)
{
sa<is_lvalue_reference<T*&&>::value == is_lvalue_ref> t1;
sa<is_rvalue_reference<T*&&>::value == is_rvalue_ref> t2;
}
struct A {};
A a;
A source() {return A();}
A* sourcep() {return 0;}
int main()
{
test1<true, false>(a);
test1<false, true>(source());
test2<false, true>(a); // { dg-error "lvalue" }
test2<false, true>(source());
test3<false, true>(&a);
test3<false, true>(sourcep());
return 0;
}
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