diff --git a/libavcodec/h264.c b/libavcodec/h264.c
index 5cbe139154..08e215d6e3 100644
--- a/libavcodec/h264.c
+++ b/libavcodec/h264.c
@@ -1385,11 +1385,11 @@ static const uint8_t *decode_nal(H264Context *h, const uint8_t *src, int *dst_le
 # if HAVE_FAST_64BIT
 #   define RS 7
     for(i=0; i+1<length; i+=9){
-        if(!((~*(uint64_t*)(src+i) & (*(uint64_t*)(src+i) - 0x0100010001000101ULL)) & 0x8000800080008080ULL))
+        if(!((~*(const uint64_t*)(src+i) & (*(const uint64_t*)(src+i) - 0x0100010001000101ULL)) & 0x8000800080008080ULL))
 # else
 #   define RS 3
     for(i=0; i+1<length; i+=5){
-        if(!((~*(uint32_t*)(src+i) & (*(uint32_t*)(src+i) - 0x01000101U)) & 0x80008080U))
+        if(!((~*(const uint32_t*)(src+i) & (*(const uint32_t*)(src+i) - 0x01000101U)) & 0x80008080U))
 # endif
             continue;
         if(i>0 && !src[i]) i--;