diff --git a/bzlib.c b/bzlib.c
index 2178655..752d5a0 100644
--- a/bzlib.c
+++ b/bzlib.c
@@ -1536,7 +1536,7 @@ void BZ_API(BZ2_bzclose) (BZFILE* b)
 /*--
    return last error code 
 --*/
-static const char *bzerrorstrings[] = {
+static const char * const bzerrorstrings[] = {
        "OK"
       ,"SEQUENCE_ERROR"
       ,"PARAM_ERROR"