Avoid segfault in sudo execution

For weeks now I have been struggling with a weird problem on 2 machines (not all of my Arch boxes, only some of them). It started with staging-x86_64-build not working (while other variants worked) then it spread to be custom makechrootpkg invocations, then to extra-x86_64-build, and lastly to another machine. I've tried blowing away the chroots and rebuilting them, reinstalled the tooling, etc. and nothing seems to touch the problem. The manifestation is simple. Right after integrity checks, I get a sefgault as it transitions to running makepkg in the chroot:

/chrootbuild: line 3:     3 Segmentation fault      (core dumped) sudo --preserve-env=SOURCE_DATE_EPOCH -iu builduser bash -c 'cd /startdir; makepkg "$@"' -bash "$@"

Every time. Any package. Any chroot.

I tried messing around with this line with just generic sudo commands like sudo true and found either -i or -u work fine in isolation, it is the combination of them that causes sudo to segfault (e.g. sudo -iu builduser true will segfault). Since -u is required here and I could not figure out why -i is required, I just removed it and found my builds all work fine.

I don't know if this is needed for some edge cases, hence this might be the wrong fix, but I'm at least opening this Draft for comment to bring attention to the problem.