if len(m2) != N {
		t.Errorf("len2(m2) = %d, want %d", len(m2), N)
	}
	for i := 0; i < N; i++ {
		if m2[i] != m[i] {
			t.Errorf("m2[%d] = %d, want %d", i, m2[i], m[i])
		}
	}
}

func TestCloneLarge(t *testing.T) {
	// See issue 64474.
	type K [17]float64 // > 128 bytes
	type V [17]float64

	var zero float64
	negZero := -zero

	for tst := 0; tst < 3; tst++ {