# HG changeset patch
# User Matthew Wala <wala1@illinois.edu>
# Date 1322613855 -3600
# Node ID a947b7cecbfeae025c8527291e0db85f60ae2517
# Parent  456f788a2768431937e99415b404023123e21c80
Avoid subtracting two pointers that don't point into the same block.

* lib/argp-help.c (hol_append): Reorder pointer subtractions so that
only pointers into the same memory block are subtracted. We cannot
assume that sizeof (ptrdiff_t) == sizeof (void *).

diff --git a/ChangeLog b/ChangeLog
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,10 @@
+2011-11-29  Matthew Wala  <wala1@illinois.edu>  (tiny change)
+
+	Avoid subtracting two pointers that don't point into the same block.
+	* lib/argp-help.c (hol_append): Reorder pointer subtractions so that
+	only pointers into the same memory block are subtracted. We cannot
+	assume that sizeof (ptrdiff_t) == sizeof (void *).
+
 2011-11-29  Eric Blake  <eblake@redhat.com>
 
 	maint.mk: add syntax check for use of compare from init.sh
diff --git a/lib/argp-help.c b/lib/argp-help.c
--- a/lib/argp-help.c
+++ b/lib/argp-help.c
@@ -891,7 +891,8 @@
 
           /* Fix up the short options pointers from HOL.  */
           for (e = entries, left = hol->num_entries; left > 0; e++, left--)
-            e->short_options += (short_options - hol->short_options);
+            e->short_options =
+              short_options + (e->short_options - hol->short_options);
 
           /* Now add the short options from MORE, fixing up its entries
              too.  */