why is std::cout convertible to void* if using g++?

Question

Why can one cast a std::ostream to a void pointer? I am not aware of any such conversion operator in std::ostream. Code below

Answer 1

Answering only the follow-up, since nicebyte's answer is perfect for the original question.

Chances are, your gcc is set up to use libstdc++ (which hasn't changed the operator yet due it being an ABI-breaking change), and your clang is set up to use libc++ (which was from the beginning intended as a C++11 standard library and isn't quite conformant in C++98 mode - it provides a bool conversion operator that is explicit in C++11).