diff --git a/libavcodec/ac3dec_fixed.c b/libavcodec/ac3dec_fixed.c
index c5b1d50a13..56b62548ec 100644
--- a/libavcodec/ac3dec_fixed.c
+++ b/libavcodec/ac3dec_fixed.c
@@ -65,7 +65,7 @@ static void scale_coefs (
     int len)
 {
     int i, shift, round;
-    int16_t mul;
+    unsigned mul;
     int temp, temp1, temp2, temp3, temp4, temp5, temp6, temp7;
 
     mul = (dynrng & 0x1f) + 0x20;