bug#31305: 27.0.50; Symlinks recognized as dirs

[Paul Eggert <eggert@cs.ucla.edu>]

> I guess that means either Paul’s fix doesn’t work on macOS 10.9, or
> David needs to update something in his build tree.


Possibly the Gnulib workaround for the macOS faccessat bug does not work 
in older macOS versions. For example, the Gnulib workaround calls the 
function 'access' on platforms lacking faccessat, and faccessat is 
missing and 'access ("foo/", F_OK)' ignores the trailing slash in older 
macOS versions, then that could explain the problem.

Suppose my guess is right. Then, if this problem occurs because the 
emacsformacosx.com build is for OS X 10.9 or earlier, then a simple fix 
is to have emacsformacosx.com build for OS X 10.10 or later, because 
Emacs can't reasonably support OS versions that Apple itself does not 
support <https://lists.gnu.org/r/emacs-devel/2018-03/msg00798.html>. On 
the other hand, if the problem occurs on OS X 10.10 or later, then 
someone should hack on the Gnulib workaround so as to port the 
workaround to OS X 10.10. I can volunteer to do the hacking in my spare 
time, but I don't have easy access to OS X 10.10 so someone else would 
need to test it.