Stack Overflow = Garbage Collection

If my functions only use a few variables and never return, then I never need anything but stack memory, and overflow is simply garbage collection. Is this possible in C?

>>2
I'm only fucked if I still need to access the old values. But the point is that I don't... a function uses a few, then goes to the next function, which uses a few, etc. By the time the old values would be pushed out, I don't need them anymore.