From: Paul Eggert <eggert@cs.ucla.edu>
Date: Mon, 11 Jul 2011 18:36:33 +0000 (-0700)
Subject: * dispnew.c (init_display): Use *_RANGE_OVERFLOW macros.
X-Git-Tag: emacs-pretest-24.0.90~104^2~152^2~163
X-Git-Url: http://git.eshelyaron.com/gitweb/?a=commitdiff_plain;h=e3c25c689524aa85ce37840fff344cc297cf42ec;p=emacs.git

* dispnew.c (init_display): Use *_RANGE_OVERFLOW macros.

The plain *_OVERFLOW macros run afoul of GCC bug 49705
<http://gcc.gnu.org/bugzilla/show_bug.cgi?id=49705>
and therefore cause GCC to emit a bogus diagnostic in some cases.
---

diff --git a/src/ChangeLog b/src/ChangeLog
index 4e69399154d..c519100b2f0 100644
--- a/src/ChangeLog
+++ b/src/ChangeLog
@@ -1,5 +1,10 @@
 2011-07-11  Paul Eggert  <eggert@cs.ucla.edu>
 
+	* dispnew.c (init_display): Use *_RANGE_OVERFLOW macros.
+	The plain *_OVERFLOW macros run afoul of GCC bug 49705
+	<http://gcc.gnu.org/bugzilla/show_bug.cgi?id=49705>
+	and therefore cause GCC to emit a bogus diagnostic in some cases.
+
 	* image.c: Integer signedness and overflow and related fixes.
 	This is not an exhaustive set of fixes, but it's time to
 	record what I've got.
diff --git a/src/dispnew.c b/src/dispnew.c
index 15d80367701..d52bbdf1d3e 100644
--- a/src/dispnew.c
+++ b/src/dispnew.c
@@ -6298,8 +6298,8 @@ init_display (void)
        change.  It's not clear what better we could do.  The rest of
        the code assumes that (width + 2) * height * sizeof (struct glyph)
        does not overflow and does not exceed PTRDIFF_MAX or SIZE_MAX.  */
-    if (INT_ADD_OVERFLOW (width, 2)
-	|| INT_MULTIPLY_OVERFLOW (width + 2, height)
+    if (INT_ADD_RANGE_OVERFLOW (width, 2, INT_MIN, INT_MAX)
+	|| INT_MULTIPLY_RANGE_OVERFLOW (width + 2, height, INT_MIN, INT_MAX)
 	|| (min (PTRDIFF_MAX, SIZE_MAX) / sizeof (struct glyph)
 	    < (width + 2) * height))
       fatal ("screen size %dx%d too big", width, height);