I had this warning when cross-building for Windows 64-bit:

> libgimp/gimpui.c:187:52: warning: passing argument 2 of
> 'gdk_win32_window_foreign_new_for_display' makes pointer from integer
> without a cast [-Wint-conversion]

> note: expected 'HWND' {aka 'struct HWND__ *'} but argument is of type 'guint32' {aka 'unsigned int'}