diff --git a/libiberty/ChangeLog b/libiberty/ChangeLog
index 4479c77f27..2a91c419dd 100644
--- a/libiberty/ChangeLog
+++ b/libiberty/ChangeLog
@@ -1,3 +1,9 @@
+2013-01-31  Kai Tietz  <ktietz@redhat.com>
+
+	PR other/543413
+	* md5.c (md5_process_block):  Handle case that size_t is
+	a wider-integer-scalar a 32-bit unsigned integer.
+
 2013-01-04  Ian Lance Taylor  <iant@google.com>
 
 	PR other/54800
diff --git a/libiberty/md5.c b/libiberty/md5.c
index 8cc0cb5fe9..b30a6b7bfc 100644
--- a/libiberty/md5.c
+++ b/libiberty/md5.c
@@ -293,8 +293,7 @@ md5_process_block (const void *buffer, size_t len, struct md5_ctx *ctx)
      length of the file up to 2^64 bits.  Here we only compute the
      number of bytes.  Do a double word increment.  */
   ctx->total[0] += len;
-  if (ctx->total[0] < len)
-    ++ctx->total[1];
+  ctx->total[1] += ((len >> 31) >> 1) + (ctx->total[0] < len);
 
   /* Process all bytes in the buffer with 64 bytes in each round of
      the loop.  */