diff --git a/libavformat/mm.c b/libavformat/mm.c
index 67d2a94bbb..347d8ebac2 100644
--- a/libavformat/mm.c
+++ b/libavformat/mm.c
@@ -175,11 +175,6 @@ static int mm_read_packet(AVFormatContext *s,
     return 0;
 }
 
-static int mm_read_close(AVFormatContext *s)
-{
-    return 0;
-}
-
 AVInputFormat mm_demuxer = {
     "mm",
     NULL_IF_CONFIG_SMALL("American Laser Games MM format"),
@@ -187,5 +182,4 @@ AVInputFormat mm_demuxer = {
     mm_probe,
     mm_read_header,
     mm_read_packet,
-    mm_read_close,
 };
diff --git a/libavformat/mmf.c b/libavformat/mmf.c
index 47b84e8c90..a0185c3ad4 100644
--- a/libavformat/mmf.c
+++ b/libavformat/mmf.c
@@ -290,11 +290,6 @@ static int mmf_read_packet(AVFormatContext *s,
     return ret;
 }
 
-static int mmf_read_close(AVFormatContext *s)
-{
-    return 0;
-}
-
 #ifdef CONFIG_MMF_DEMUXER
 AVInputFormat mmf_demuxer = {
     "mmf",
@@ -303,7 +298,7 @@ AVInputFormat mmf_demuxer = {
     mmf_probe,
     mmf_read_header,
     mmf_read_packet,
-    mmf_read_close,
+    NULL,
     pcm_read_seek,
 };
 #endif