diff --git a/libavutil/internal.h b/libavutil/internal.h
index 13dbd3b966..5c2cd99dcc 100644
--- a/libavutil/internal.h
+++ b/libavutil/internal.h
@@ -259,6 +259,7 @@ void avpriv_request_sample(void *avc,
 /**
  * A wrapper for open() setting O_CLOEXEC.
  */
+av_warn_unused_result
 int avpriv_open(const char *filename, int flags, ...);
 
 int avpriv_set_systematic_pal2(uint32_t pal[256], enum AVPixelFormat pix_fmt);