diff --git a/ffmpeg.c b/ffmpeg.c
index 33152c1059..1f61d29fbb 100644
--- a/ffmpeg.c
+++ b/ffmpeg.c
@@ -3259,7 +3259,7 @@ static int transcode(void)
                     ost->logfile = NULL;
                 }
                 av_freep(&ost->st->codec->subtitle_header);
-                av_free(ost->forced_kf_pts);
+                av_freep(&ost->forced_kf_pts);
                 av_dict_free(&ost->opts);
                 av_dict_free(&ost->swr_opts);
                 av_dict_free(&ost->resample_opts);