bignum.c:927
static VALUE
rb_big_eql(x, y)
    VALUE x, y;
{
    if (TYPE(y) != T_BIGNUM) return Qfalse;
    if (RBIGNUM(x)->sign != RBIGNUM(y)->sign) return Qfalse;
    if (RBIGNUM(x)->len != RBIGNUM(y)->len) return Qfalse;
    if (MEMCMP(BDIGITS(x),BDIGITS(y),BDIGIT,RBIGNUM(y)->len) != 0) return Qfalse;
    return Qtrue;
}
