# HG changeset patch
# User Aidan Kehoe <kehoea@parhasard.net>
# Date 1215702359 -7200
# Node ID dbf79a1732bafb35ad5b7e86e8e535e95ec074ca
# Parent  86283c809984f21bfb6f3fd971d2774b61e03f0a
Don't try to get text width for the null font instance, mswindows

2008-07-10  Aidan Kehoe  <kehoea@parhasard.net>

	* redisplay-msw.c (mswindows_text_width_single_run):
	Explicitly check for the null font instance, and return zero if
	so. Avoids the crash documented in
	http://mid.gmane.org/18473.32468.712317.149457@parhasard.net .

diff -r 86283c809984 -r dbf79a1732ba src/ChangeLog
--- a/src/ChangeLog	Sun Jul 06 19:46:19 2008 +0300
+++ b/src/ChangeLog	Thu Jul 10 17:05:59 2008 +0200
@@ -1,3 +1,10 @@
+2008-07-10  Aidan Kehoe  <kehoea@parhasard.net>
+
+	* redisplay-msw.c (mswindows_text_width_single_run): 
+	Explicitly check for the null font instance, and return zero if
+	so. Avoids the crash documented in
+	http://mid.gmane.org/18473.32468.712317.149457@parhasard.net .
+
 2008-05-27  Aidan Kehoe  <kehoea@parhasard.net>
 
 	* editfns.c (Ftranslate_region):  
diff -r 86283c809984 -r dbf79a1732ba src/redisplay-msw.c
--- a/src/redisplay-msw.c	Sun Jul 06 19:46:19 2008 +0300
+++ b/src/redisplay-msw.c	Thu Jul 10 17:05:59 2008 +0200
@@ -148,6 +148,15 @@
   Lisp_Object font_inst = FACE_CACHEL_FONT (cachel, run->charset);
   SIZE size;
 
+  /* The X11 code doesn't have to do this explicitly, because there we trust
+     the font instance to know whether it's actually proportional or not,
+     and we use the zero width that is stored in the monospace null font
+     instance.  */
+  if (EQ (Vthe_null_font_instance, font_inst))
+    {
+      return 0;
+    }
+
 #if 0 /* #### not the way of ikeyama's ws */
   if (!fi->proportional_p || !hdc)
     {