m := &sync.Map{}
	if m.CompareAndSwap(m, nil, 42) {
		// See https://go.dev/issue/51972#issuecomment-1126408637.
		t.Fatalf("CompareAndSwap on a non-existing key succeeded")
	}
}

func TestMapRangeNoAllocations(t *testing.T) { // Issue 62404
	testenv.SkipIfOptimizationOff(t)
	var m sync.Map
	allocs := testing.AllocsPerRun(10, func() {
		m.Range(func(key, value any) bool {
			return true
		})
	})