Clang 15 build error (incompatible pointer to integer conversion)

Hello,

MSYS2 started to use Clang 15 and they attempted to re-build GIMP 2.10.32 and 2.99.12

There is a warning which turned to error in Clang 15:

 ../../gimp-2.10.32/libgimp/gimpprogressbar.c:192:12: error: incompatible pointer to integer conversion returning 'HGDIOBJ' (aka 'void *') from a function with result type 'guint32' (aka 'unsigned int') [-Wint-conversion]
      return GDK_WINDOW_HWND (gtk_widget_get_window (GTK_WIDGET (window)));
             ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

"The -Wint-conversion warning diagnostic for implicit int <-> pointer conversions now defaults to an error in all C language modes. It may be downgraded to a warning with -Wno-error=int-conversion, or disabled entirely with -Wno-int-conversion."

https://releases.llvm.org/15.0.0/tools/clang/docs/ReleaseNotes.html

How we could fix this in the source code beside tweaking the compiler flags?