MSVC build error in gdk-pixbuf

[John Emmas <johne53 tiscali co uk>]

Hi guys.  I'm hoping this is the right place to report a build error 
with gdk-pixbuf (git master).

I updated a few days ago and I'm getting a compiler error at line 330 of 
io-png.c which looks like this:-

      for (i = 0, ptr = pixbuf->pixels; i < h; i++, ptr += 
pixbuf->rowstride)

MSVC is complaining that it can't increment 'ptr' (in the bit that says 
"ptr += pixbuf->rowstride").  The compiler gives me error C2036 
('gpointer' has unknown size).  'ptr' gets declared like this at line 271:-

      gpointer ptr;

If I change the declaration to this:-

      guchar *ptr;

It now compiles.  Is that an acceptable change?

John