diff --git a/libavcodec/mpeg4video_parser.c b/libavcodec/mpeg4video_parser.c
index c331435cc1..5f3b19d5aa 100644
--- a/libavcodec/mpeg4video_parser.c
+++ b/libavcodec/mpeg4video_parser.c
@@ -20,6 +20,8 @@
  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
  */
 
+#define UNCHECKED_BITSTREAM_READER 1
+
 #include "parser.h"
 #include "mpegvideo.h"
 #include "mpeg4video.h"
diff --git a/libavcodec/mpeg4videodec.c b/libavcodec/mpeg4videodec.c
index e620f75687..de5e862827 100644
--- a/libavcodec/mpeg4videodec.c
+++ b/libavcodec/mpeg4videodec.c
@@ -20,6 +20,8 @@
  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
  */
 
+#define UNCHECKED_BITSTREAM_READER 1
+
 #include "libavutil/opt.h"
 #include "mpegvideo.h"
 #include "mpeg4video.h"