b.Fatal("b1 != b2")
		}
	}
	b.SetBytes(int64(len(b1)))
}

func BenchmarkCompareBytesBigIdentical(b *testing.B) {
	b.StopTimer()
	b1 := make([]byte, 0, 1<<20)
	for len(b1) < 1<<20 {
		b1 = append(b1, "Hello Gophers!"...)
	}
	b2 := b1
	b.StartTimer()
	for i := 0; i < b.N; i++ {
		if Compare(b1, b2) != 0 {
			b.Fatal("b1 != b2")
		}
	}
	b.SetBytes(int64(len(b1)))

}

// Set sets z = x and returns z.
func (z *Int) Set(x *Int) *Int {
	z.doinit()
	C.mpz_set(&z.i[0], &x.i[0])
	return z
}

// SetBytes interprets b as the bytes of a big-endian integer
// and sets z to that value.
func (z *Int) SetBytes(b []byte) *Int {
	z.doinit()
	if len(b) == 0 {
		z.SetInt64(0)
	} else {
		C.mpz_import(&z.i[0], C.size_t(len(b)), 1, 1, 1, 0, unsafe.Pointer(&b[0]))
	}