Checking the registers is easy enough; just push them onto the stack and a quick check of several consecutive memory addresses and you are done. The other way

Checking the registers is easy enough; just push them onto the stack and a quick check of several consecutive memory addresses and you are done. The other way to improve GC if you are using C is to make sure your local allocations are in fact local; use alloca() and friends (but only for sub page sizes, possibly less if you are doing lots of local allocations). This will reduce the amount of GC required. As far as Red Zone goes if you are in the GC then you can't be in another local function; unless you are running your GC pre-emptively (signals etc), in which case you need to be much much more careful.