diff --git a/libavformat/matroska.c b/libavformat/matroska.c
index eded899f47..e541d2d9ea 100644
--- a/libavformat/matroska.c
+++ b/libavformat/matroska.c
@@ -21,7 +21,7 @@
 
 #include "matroska.h"
 
-CodecTags ff_mkv_codec_tags[]={
+const CodecTags ff_mkv_codec_tags[]={
 //    {"V_MS/VFW/FOURCC"  , CODEC_ID_NONE},
     {"V_UNCOMPRESSED"   , CODEC_ID_RAWVIDEO},
     {"V_MPEG4/ISO/ASP"  , CODEC_ID_MPEG4},
diff --git a/libavformat/matroska.h b/libavformat/matroska.h
index f46337b87f..fcfde37a03 100644
--- a/libavformat/matroska.h
+++ b/libavformat/matroska.h
@@ -191,6 +191,6 @@ typedef struct CodecTags{
 /* max. depth in the EBML tree structure */
 #define EBML_MAX_DEPTH 16
 
-extern CodecTags ff_mkv_codec_tags[];
+extern const CodecTags ff_mkv_codec_tags[];
 
 #endif /* FFMPEG_MATROSKA_H */