I realize this is more a MinGW/GCC question than a Qt question, but at this point MinGW/GCC is pretty much a black box to me, and I couldn’t find anything helpful by searching for SHChangeNotifyRegister and MinGW.

How do I access a Windows function the definition of which is missing from the MinGW header files?

SHChangeNotifyRegister belongs in shlobj.h — it’s there in the Windows Platform SDK (been there since Windows 2000), but it’s nowhere in the MinGW version. It’s nowhere in any file under my Qt 4.6 installation. I can copy the definition from the Platform SDK to get my code to compile, but (unsurprisingly) the link step fails.

Of course, it has to be there in the actual Windows run-time libraries — how do I tell the linker how to find it?