kc3-lang/libtommath

diff --git a/bn_s_mp_reverse.c b/bn_s_mp_reverse.c
index 623d51e..c549e60 100644
--- a/bn_s_mp_reverse.c
+++ b/bn_s_mp_reverse.c
@@ -9,8 +9,8 @@ void s_mp_reverse(unsigned char *s, size_t len)
    size_t   ix, iy;
    unsigned char t;
 
-   ix = 0;
-   iy = len - 1;
+   ix = 0u;
+   iy = len - 1u;
    while (ix < iy) {
       t     = s[ix];
       s[ix] = s[iy];