diff --git a/libavcodec/libamr.c b/libavcodec/libamr.c
index 24d2655821..241fc994b7 100644
--- a/libavcodec/libamr.c
+++ b/libavcodec/libamr.c
@@ -656,6 +656,7 @@ static int amr_wb_decode_frame(AVCodecContext * avctx,
     uint8_t*amrData=buf;
     int mode;
     int packet_size;
+    static const uint8_t block_size[16] = {18, 23, 33, 37, 41, 47, 51, 59, 61, 6, 6, 0, 0, 0, 1, 1};
 
     if(buf_size==0) {
         /* nothing to do */