diff --git a/libavutil/internal.h b/libavutil/internal.h
index 2010e3008a75b63c9ca91246ba0802201cc49887..c1f849fb3f05913aa7c7bb677bbd72f7c487154c 100644
--- a/libavutil/internal.h
+++ b/libavutil/internal.h
@@ -164,8 +164,6 @@ static inline av_const int FASTDIV(int a, int b)
 
 extern const uint8_t ff_sqrt_tab[256];
 
-static inline int av_log2_16bit(unsigned int v);
-
 static inline av_const unsigned int ff_sqrt(unsigned int a)
 {
     unsigned int b;