diff --git a/ChangeLog b/ChangeLog
index 60eaae97..f83afe0d 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,8 @@
+2010-06-10  Bob Friesenhahn  <bfriesen@simple.dallas.tx.us>
+
+	* libtiff/tiffiop.h (TIFFSafeMultiply): Work properly if
+	multiplier is zero.
+
 2010-06-09  Bob Friesenhahn  <bfriesen@simple.dallas.tx.us>
 
 	* libtiff/tif_fax3.c (Fax3SetupState): Yesterday's fix for
diff --git a/libtiff/tiffiop.h b/libtiff/tiffiop.h
index 4fecb7cd..12321386 100644
--- a/libtiff/tiffiop.h
+++ b/libtiff/tiffiop.h
@@ -1,4 +1,4 @@
-/* $Id: tiffiop.h,v 1.77 2010-06-09 17:17:13 bfriesen Exp $ */
+/* $Id: tiffiop.h,v 1.78 2010-06-10 22:53:11 bfriesen Exp $ */
 
 /*
  * Copyright (c) 1988-1997 Sam Leffler
@@ -270,7 +270,7 @@ struct tiff {
 #define TIFFroundup_64(x, y) (TIFFhowmany_64(x,y)*(y))
 
 /* Safe multiply which returns zero if there is an integer overflow */
-#define TIFFSafeMultiply(t,v,m) ((((t)v*m)/(t)m == (t)v) ? (t)v*m : (t)0)
+#define TIFFSafeMultiply(t,v,m) ((((t)m != (t)0) && (((t)v*m)/(t)m == (t)v)) ? (t)v*m : (t)0)
 
 #define TIFFmax(A,B) ((A)>(B)?(A):(B))
 #define TIFFmin(A,B) ((A)<(B)?(A):(B))
diff --git a/m4/argz.m4 b/m4/argz.m4
deleted file mode 100644
index 1f8d67d0..00000000
--- a/m4/argz.m4
+++ /dev/null
@@ -1,79 +0,0 @@
-# Portability macros for glibc argz.                    -*- Autoconf -*-
-#
-#   Copyright (C) 2004, 2005, 2006, 2007 Free Software Foundation, Inc.
-#   Written by Gary V. Vaughan <gary@gnu.org>
-#
-# This file is free software; the Free Software Foundation gives
-# unlimited permission to copy and/or distribute it, with or without
-# modifications, as long as this notice is preserved.
-
-# serial 5 argz.m4
-
-AC_DEFUN([gl_FUNC_ARGZ],
-[gl_PREREQ_ARGZ
-
-AC_CHECK_HEADERS([argz.h], [], [], [AC_INCLUDES_DEFAULT])
-
-AC_CHECK_TYPES([error_t],
-  [],
-  [AC_DEFINE([error_t], [int],
-   [Define to a type to use for `error_t' if it is not otherwise available.])
-   AC_DEFINE([__error_t_defined], [1], [Define so that glibc/gnulib argp.h
-    does not typedef error_t.])],
-  [#if defined(HAVE_ARGZ_H)
-#  include <argz.h>
-#endif])
-
-ARGZ_H=
-AC_CHECK_FUNCS([argz_append argz_create_sep argz_insert argz_next \
-	argz_stringify], [], [ARGZ_H=argz.h; AC_LIBOBJ([argz])])
-
-dnl if have system argz functions, allow forced use of 
-dnl libltdl-supplied implementation (and default to do so
-dnl on "known bad" systems). Could use a runtime check, but
-dnl (a) detecting malloc issues is notoriously unreliable
-dnl (b) only known system that declares argz functions,
-dnl     provides them, yet they are broken, is cygwin
-dnl     releases prior to 16-Mar-2007 (1.5.24 and earlier)
-dnl So, it's more straightforward simply to special case 
-dnl this for known bad systems.
-AS_IF([test -z "$ARGZ_H"],
-    [AC_CACHE_CHECK(
-        [if argz actually works],
-        [lt_cv_sys_argz_works],
-        [[case $host_os in #(
-	 *cygwin*)
-	   lt_cv_sys_argz_works=no
-	   if test "$cross_compiling" != no; then
-	     lt_cv_sys_argz_works="guessing no"
-	   else
-	     lt_sed_extract_leading_digits='s/^\([0-9\.]*\).*/\1/'
-	     save_IFS=$IFS
-	     IFS=-.
-	     set x `uname -r | sed -e "$lt_sed_extract_leading_digits"`
-	     IFS=$save_IFS
-	     lt_os_major=${2-0}
-	     lt_os_minor=${3-0}
-	     lt_os_micro=${4-0}
-	     if test "$lt_os_major" -gt 1 \
-		|| { test "$lt_os_major" -eq 1 \
-		  && { test "$lt_os_minor" -gt 5 \
-		    || { test "$lt_os_minor" -eq 5 \
-		      && test "$lt_os_micro" -gt 24; }; }; }; then
-	       lt_cv_sys_argz_works=yes
-	     fi
-	   fi
-	   ;; #(
-	 *) lt_cv_sys_argz_works=yes ;;
-	 esac]])
-     AS_IF([test $lt_cv_sys_argz_works = yes],
-        [AC_DEFINE([HAVE_WORKING_ARGZ], 1,
-                   [This value is set to 1 to indicate that the system argz facility works])],
-        [ARGZ_H=argz.h
-        AC_LIBOBJ([argz])])])
-
-AC_SUBST([ARGZ_H])
-])
-
-# Prerequisites of lib/argz.c.
-AC_DEFUN([gl_PREREQ_ARGZ], [:])