diff --git a/fs/ext3/bitmap.c b/fs/ext3/bitmap.c
index b9176ee..6afc39d 100644
--- a/fs/ext3/bitmap.c
+++ b/fs/ext3/bitmap.c
@@ -13,7 +13,7 @@
 
 #ifdef EXT3FS_DEBUG
 
-static int nibblemap[] = {4, 3, 3, 2, 3, 2, 2, 1, 3, 2, 2, 1, 2, 1, 1, 0};
+static const int nibblemap[] = {4, 3, 3, 2, 3, 2, 2, 1, 3, 2, 2, 1, 2, 1, 1, 0};
 
 unsigned long ext3_count_free (struct buffer_head * map, unsigned int numchars)
 {