diff --git a/src/bin/fp_toradix_n.c b/src/bin/fp_toradix_n.c
index 5c9bf62..c26a02b 100644
--- a/src/bin/fp_toradix_n.c
+++ b/src/bin/fp_toradix_n.c
@@ -13,7 +13,7 @@ int fp_toradix_n(fp_int *a, char *str, int radix, int maxlen)
 {
    int digs;
    fp_int t;
-   fp_digit d;
+   fp_digit d = 0;
    char *_s = str;
 
    /* check range of the radix */