The following code uses return type deduction (auto) and different methods for L-value and R-value objects. It seems when combining the two, gcc 4.9.2 has problems with overload resolution: "call of overloaded 'f()' is ambiguous".
Is this a bug or just another strange C++ corner case? Clang accepts it as expected.
struct T {
auto f() & {
return int{0};
}
auto f() && {
return string{""};
}
};
void test_it() {
//Calling with L-value object. Fails with "call of overloaded 'f()' is ambiguous").
T t;
int s = t.f();
//Calling with R-value object. Fails with "call of overloaded 'f()' is ambiguous").
string i = T{}.f();
}
The example can be studied using online compilers here:
gcc 4.9.2: http://goo.gl/IE19y8
clang 3.5.1: http://goo.gl/FRbD8Z
