porting the method '__popcnt' to mingw

In my Microsoft specific code I have something like this (which works and builds fine)

wfx->Channels = __popcnt(type);

Mingw has a problem recognizing __popcnt any suggestions on what I could use instead of that ? This page says its declared in #include <intrin.h> however adding that did not help. Any suggestions on what I could replace it with ? I do not have access to a Microsoft compiler and I cannot dig deeper into the method.