I think I did not describe the problem properly. The problem is:
1) Only on W32 platform.
2) Has nothing to do with GBK. The problem arises together with 
create-fontset-from-fontset-spec, no matter I use GBK or GB2312.

The patch works indeed. In fact, "font->tm.tmMaxCharWidth" is double of 
"font->tm.tmAveCharWidth", I think that's where the problem is.

2005/9/6, Jason Rumney <jasonr@gnu.org>:
> 
> Sun Yijiang wrote:
> 
> > I think I've found the problem, here is the patch of w32fns.c (against
> > revision 1.256). I don't know the detail, but this patch works.
> >
> > 
> --------------------------------------8<--------------------------------------
> > --- w32fns.c 2005-08-08 09:45:47.000000000 +0800
> > +++ w32fns-fix.c 2005-09-06 15:32:01.275812264 +0800
> > @@ -4545,7 +4545,7 @@
> > /* Fill out details in lf according to the font that was
> > actually loaded. */
> > lf.lfHeight = font->tm.tmInternalLeading - font->tm.tmHeight;
> > - lf.lfWidth = font->tm.tmMaxCharWidth;
> > + lf.lfWidth = font->tm.tmAveCharWidth;
> > lf.lfWeight = font->tm.tmWeight;
> > lf.lfItalic = font->tm.tmItalic;
> > lf.lfCharSet = font->tm.tmCharSet;
> > 
> --------------------------------------8<--------------------------------------
> 
> How can this work?
> 
> The problem you reported was for BDF fonts used to display the GBK
> character sets.
> The fix above affects only Windows system fonts.
> 
>