diff --git a/gdb/ChangeLog b/gdb/ChangeLog
index fe69ce6d134..4a60c081923 100644
--- a/gdb/ChangeLog
+++ b/gdb/ChangeLog
@@ -1,3 +1,8 @@
+2012-09-28  Yao Qi  <yao@codesourcery.com>
+
+	* mi/mi-main.c (mi_cmd_data_write_memory_bytes): Emit error
+	when the length of content is not an even number.
+
 2012-09-27  Tom Tromey  <tromey@redhat.com>
 
 	Fix https://bugzilla.redhat.com/show_bug.cgi?id=849357
diff --git a/gdb/mi/mi-main.c b/gdb/mi/mi-main.c
index f1d21bcf6eb..f73d4f8796b 100644
--- a/gdb/mi/mi-main.c
+++ b/gdb/mi/mi-main.c
@@ -1672,6 +1672,10 @@ mi_cmd_data_write_memory_bytes (char *command, char **argv, int argc)
 
   addr = parse_and_eval_address (argv[0]);
   cdata = argv[1];
+  if (strlen (cdata) % 2)
+    error (_("Hex-encoded '%s' must have an even number of characters."),
+	   cdata);
+
   len = strlen (cdata)/2;
 
   data = xmalloc (len);