diff --git a/libavcodec/hevc_mp4toannexb_bsf.c b/libavcodec/hevc_mp4toannexb_bsf.c
index 09bce5b34c..d0f1b94f0e 100644
--- a/libavcodec/hevc_mp4toannexb_bsf.c
+++ b/libavcodec/hevc_mp4toannexb_bsf.c
@@ -164,7 +164,7 @@ static int hevc_mp4toannexb_filter(AVBSFContext *ctx, AVPacket *out)
         if (ret < 0)
             goto fail;
 
-        if (add_extradata)
+        if (extra_size)
             memcpy(out->data + prev_size, ctx->par_out->extradata, extra_size);
         AV_WB32(out->data + prev_size + extra_size, 1);
         bytestream2_get_buffer(&gb, out->data + prev_size + 4 + extra_size, nalu_size);