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

[Justin Schell]

> Justin, I've not had any reports of similar issues to yours, but I
> have just managed to reproduce the error by breaking my Emacs.app
> bundle in a very specific way. What folders do you have under
> "Emacs.app/Contents/MacOS/lib/gcc" in your app bundle? There's
> supposed to be a folder called "10". I reproduced the issue by
> renaming my "10" folder so it no longer matches regexp "^[0-9]+$". If
> you have something else, it's time to debug how that happened and
> where my build script went wrong.

Jim, I do have a `Emacs.app/Contents/MacOS/lib/gcc/10` directory.

However, I seem to have found the issue. Since I had been doing builds
from several different branches and commits, I had been naming the
base-dir of the Emacs.app in concert with the name of the build
tarball that `build-emacs-for-macos` produces to keep track of which
was which. E.g.,
'Emacs.app-[feature-native-comp][2021-02-03][1f626e9][macOS-10.15][x86_64].app'.
If I rename that to just 'Emacs.app', I can no longer reproduce the
`M-x report-emacs-bug` "Wrong type argument: stringp, nil" error.
Thus, somewhere the `native-compile-setup-environment-variables` patch
code doesn't seem to handle that sort of invocation-dir name. I don't
have time to debug exactly where right now, but let me know if you
need anything else.

Glad that it seems that we've found the root issue (at least
approximately). Thanks for the help, all.

Justin