s1                 18 string.c         const uchar *s1, *s2;
s1                 20 string.c         s1 = v1;
s1                 23 string.c           if(*s1 != *s2)
s1                 24 string.c             return *s1 - *s2;
s1                 25 string.c           s1++, s2++;