You are correct. At least the do... while statement is a common c macro trick to make sure a macro has its own scope. The idea is that a compiler will optimize

You are correct. At least the do... while statement is a common c macro trick to make sure a macro has its own scope. The idea is that a compiler will optimize the do....while statement away, so it does not have any runtime overhead. The wile...while(0) statement is new for me (didn't know this is actually legal syntax), but I suspect it's done for similar reasons.