[cpr]

Gosh, all that to save one byte? ;-)

[jhallenworld]

Suppose you have only 4 entries (perhaps very large) in your ring. You might care about this.

[jonsen]

That byte will be needed elsewhere to make it multitasking safe.

[codehero]

I'm running it on a system with 512 bytes of RAM and multiple queues...saving 1 byte helps. I do not need extra space for synchronization; I can enable/disable interrupts without extra RAM required.