** Compare two strings, case sensitive.
** Return zero if they match, -1 if s1<s2, +1 is s1>s2;
*/
-cell_t ffCompare( const char *s1, cell_t len1, const char *s2, int32_t len2 )
+cell_t ffCompare( const char *s1, cell_t len1, const char *s2, cell_t len2 )
{
cell_t i, result, n, diff;