var (
	onceFunc = sync.OnceFunc(func() {})

	onceFuncOnce sync.Once
)

func doOnceFunc() {
	onceFuncOnce.Do(func() {})
}

func BenchmarkOnceFunc(b *testing.B) {
	b.Run("v=Once", func(b *testing.B) {
		b.ReportAllocs()
		for i := 0; i < b.N; i++ {
			// The baseline is direct use of sync.Once.
			doOnceFunc()
		}
	})
	b.Run("v=Global", func(b *testing.B) {
		b.ReportAllocs()