Stack probe puzzle

matklad · May 30, 2025, 1:48pm

To preserve my sanity, I had to seal the rabbit hole:

github.com/tigerbeetle/tigerbeetle

ci: run fuzzers with smaller stacks

main ← matklad/no-stacks

opened 02:51PM - 28 May 25 UTC

matklad

+29 -0

Two changes here: * Set stack size for vopr and fuzz to 4*MiB. Zig's default …stack size is 16*MiB, but we want to make sure that we have ample free space. Given that we don't have a billion of dependencies, and that recursion is banned by TigerStyle, our stack size should be pretty shallow. * Eagerly fault-in the stack on startup for fuzzers, to, ahem, scare out the ghosts out of our CFO machines: https://ziggit.dev/t/stack-probe-puzzle/10291/1 This _is_ a work-around, but, based on the fact that it _only_ affects forest_fuzz which does a lot of allocation and de-allocation, I do think there isn't any issue with our code, and, given that the root cause hasn't reveal itself after 3 days of investigation, it seems better to just table this for now.

I couldn’t bring myself to deleting the original core dump file. It will be waiting for the next foolish adventurer.

https://github.com/matklad/repros/releases/download/artifacts/core.zst