Heads up: Problems with parallel make

[Ken Brown]

On 2/27/2023 4:41 PM, Brian Inglis via Cygwin-apps wrote:
> Looks like the 4.4.1 release disables FIFO on Hurd and Cygwin.
> Will be interesting to see if it is based on config test, for clues to 
> what it does not like, or just system?

In the case of HURD, it's because of failing tests in the test suite. 
In the case of Cygwin, it's because of the problem I reported, in which 
parallel make using a FIFO sometimes hangs when building TeX Live.

Anyone who wants to test this with their own builds can build make with

   CPPFLAGS=-DJOBSERVER_USE_FIFO=1

That will re-enable the use a FIFO for the jobserver.  One can then 
force make to use a pipe on a given project by using the make option

   --jobserver-style=pipe

I plan to do this myself, since I hope to debug the FIFO problem the 
next time I see it.  It's not easy to catch, because it doesn't happen 
with every build of TeX Live.  And when it does happen, the build has 
typically been going on for close to two hours before it hangs.

P.S. Marco, I don't know how much trouble you want to go to on this, but 
when you release make-4.4.1, you might also make a test release with 
CPPFLAGS set as above.  That would make it easier for adventurous people 
to try builds that use a FIFO.