non-threaded rts and CollectGarbage

Hi there! in the non-threaded rts we use itimer to do light weight scheduling of threads via SIGALRM signals. I'm seeing quite a bit of heap corruption on aarch64, and it appears that I also see a lot of signal handling in the GC, for example during evacuate. Is there a fundamental reason why we can't just disable the timer during GC? Cheers, Moritz