Are explicit conversion operators allowed in braced initializer lists?

Question

The following code compiles with GCC 4.9.2 but not with Clang 3.5.0:

#include 

class Foo
{
public:
  explicit operator std::string() const;
};         


        

Answer 1

This seems to be a Clang bug. [over.match.list]/1:

When objects of non-aggregate class type T are list-initialized (8.5.4), overload resolution selects the constructor in two phases:

• [..]
• If no viable initializer-list constructor is found, overload resolution is performed again, where the candidate functions are all the constructors of the class T and the argument list consists of the elements of the initializer list.

Since the second line compiles fine, there is an inconsistency: They should be equivalent when it comes to overload resolution.