diff --git a/libavcodec/msmpeg4.c b/libavcodec/msmpeg4.c
index 420dc4dc67..8ca17c99d8 100644
--- a/libavcodec/msmpeg4.c
+++ b/libavcodec/msmpeg4.c
@@ -70,7 +70,7 @@ static int msmpeg4v12_decode_mb(MpegEncContext *s, DCTELEM block[6][64]);
 static int msmpeg4v34_decode_mb(MpegEncContext *s, DCTELEM block[6][64]);
 
 /* vc1 externs */
-extern uint8_t wmv3_dc_scale_table[32];
+extern const uint8_t wmv3_dc_scale_table[32];
 
 #ifdef DEBUG
 int intra_count = 0;
diff --git a/libavutil/base64.c b/libavutil/base64.c
index 0f497981c2..8567c9924b 100644
--- a/libavutil/base64.c
+++ b/libavutil/base64.c
@@ -29,7 +29,7 @@
 #include "base64.h"
 
 /* ---------------- private code */
-static uint8_t map2[] =
+static const uint8_t map2[] =
 {
     0x3e, 0xff, 0xff, 0xff, 0x3f, 0x34, 0x35, 0x36,
     0x37, 0x38, 0x39, 0x3a, 0x3b, 0x3c, 0x3d, 0xff,