[Bug testsuite/66005] libgomp make check time is excessive

["ro at CeBiTec dot Uni-Bielefeld.DE" <gcc-bugzilla@gcc.gnu.org>]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=66005

--- Comment #15 from ro at CeBiTec dot Uni-Bielefeld.DE <ro at CeBiTec dot Uni-Bielefeld.DE> ---
> --- Comment #14 from Thomas Schwinge <tschwinge at gcc dot gnu.org> ---
> (In reply to Eric Gallager from comment #12)
>> Note that there's a gnulib module for flock:
>> https://www.gnu.org/software/gnulib/manual/html_node/flock.html
>
> I'd see that one -- but it also says: "the replacement function does not really
> work", so I don't think that's useful?

Besides, this only provides a replacement for the system call; we'd
still have to implement flock(1) ourselves and I'd rather not see us go
there.

> (In reply to Jakub Jelinek from comment #13)
>> And fcntl in tclx.
>
> Seen that, too -- but is TclX something that people actually have
> available/installed?  (Rainer?)

It's not available in packaged form on any of the targets I mentioned
(Solaris, macOS, AIX).  Besides, adding something like this feels quite
heavy-handed to me.

>> Anyway, I think choosing between flock(1) and some
>> python file locking would be better than using perl which is only needed in
>> maintainer mode and not otherwise.
>
> Rainer, would a 'python3' variant work for you?

Not really: python3 isn't available on older macOS systems, and again:
adding a python requirement (even for python2 in such a limited case)
seems to go overboard to me.

While I personally don't have a problem with requiring perl (it's needed
to support shared library versioning on Solaris), the same argument
applies.

My strong preference would be to use Tcl core means only, thus adding no
additional requirement.  I found a couple of suggestions on how to do
this:

https://wiki.tcl-lang.org/page/How+do+I+manage+lock+files+in+a+cross+platform+manner+in+Tcl
https://wiki.tcl-lang.org/page/Serializing+things+via+file+locks

effectively matching Jakub's suggestion.