bug#45701: 28.0.50; [feature/native-comp] (33b8ce8) `M-x report-emacs-bug` error: "Wrong type argument: stringp, nil"

[Justin Schell <justinmschell@gmail.com>]

I'm still seeing the `M-x report-emacs-bug` error: "Wrong type
argument: stringp, nil" issue in builds of `feature/native-comp` made
since updating Xcode and all Homebrew deps this morning.

However, this issue does indeed seem to be caused by something going
awry in the build process on my machine as I just rebuilt from a
commit that I had been using for quite a while (`cb293cf` from
2020-09-10) and I'm now seeing this issue in that build as well. I
still have the build of that commit that I ran in September and `M-x
report-emacs-bug` works fine. I saved the build log and scrolled
through it, but didn't see anything obviously wrong apart from a few
compiler warnings.

Note that I don't see that issue in builds from `master`, so it seems
to be related to a dependency of `feature/native-comp`. I also saved
the build log from a (successful) `master` build. I can try to compare
the logs from the two branches, but I'm not sure if that will be
fruitful.

Any other suggestions for how to debug this issue?

Justin

PS - Something that confused the situation yesterday when I was trying
to isolate the "bad" commit is that due to how Github presents it's
commit logs, specifically with merge commits, I didn't realize that
when I was attempting to build a commit from `feature/native-comp`,
sometimes I was actually building a commit from `master`. Executing a
build with the format from
https://github.com/jimeh/build-emacs-for-macos/issues/6, e.g.,
`./build-emacs-for-macos --git-sha
0f561ee55348ff451600cc6027db5940ee14606f feature/native-comp` is
actually building building a commit from `master` and specifying the
`feature/native-comp` branch name in that command is superfluous.