bug#30350: 27.0.50; Newest master can't run processes on macOS

[Alan Third]

On Sun, Feb 04, 2018 at 08:20:48PM +0000, Philipp Stephani wrote:
> Philipp <p.stephani2@gmail.com> schrieb am So., 4. Feb. 2018 um 21:17 Uhr:
> 
> >
> > For some reason the newest master can't seem to start subprocesses on
> > macOS:
> >
> > emacs -batch -Q --eval='(call-process "/usr/bin/true")'
> > Searching for program: Is a directory, /usr/bin/true
> >
> > Needless to say, /usr/bin/true is a regular file.
> >
> >
> According to 'git bisect', the problematic commit is
> 
> commit 327d251f8a857350a78029c31c7ab3f9797cc727
> 
> Author: Paul Eggert <eggert@cs.ucla.edu>
> 
> Date:   Sat Feb 3 12:10:19 2018 -0800
> 
> 
>     Avoid EOVERFLOW problems with file-directory-p

Oddly if you do

    (file-accessible-directory-p "/usr/bin/true")

it works correctly, but then once you run

    (call-process "/usr/bin/true")

file-accessible-directory-p incorrectly returns true on subsequent
calls. Paul’s commit didn’t make any real changes to
file-accessible-directory-p so I suspect this problem is older.

Incidentally it looks like, on MSDOS, file_directory_p calls
file_accessible_directory_p, which calls file_directory_p.
-- 
Alan Third