Re: test-pthread-rwlock failure on Pop!_OS 22.04 LTS

[Pádraig Brady]

On 09/08/2024 11:03, Bruno Haible wrote:
> Pádraig Brady wrote:
> > FYI coreutils CI started failing with this on cfarm13.cfarm.net (debian 11.9) 
> > with:
> >
> > FAIL: test-pthread-rwlock-waitqueue
> > ===================================
> > test-pthread-rwlock-waitqueue.c:234: assertion 'startswith (do_test ("RRRRR"), " R1 
> > R2 R3 R4 R5")' failed
> > FAIL test-pthread-rwlock-waitqueue (exit status: 134)
>
> I can't reproduce it on that machine, even in 100 runs. Probably the machine
> was under load while your CI was running.
>
> Let me avoid the (optimistic) 5 ms interval. This makes the test run for a
> longer time, but that is less of a problem than a failing test.

It failed again the same way with the latest gnulib.
Note the test is run with `make -j24 check` from crontab.

The failure is intermittent from crontab,
and I couldn't repro manually.

I did however notice different output depending on
whether the test was run in the foreground or background
(which might explain why crontab may be a trigger here).

If I run the test in the foreground with 
./gnulib-tests/test-pthread-rwlock-waitqueue
I don't see any of the "... => ..." lines output.
Though I do see those when running in the background like:
./gnulib-tests/test-pthread-rwlock-waitqueue >out.bg 2>&1 &
Note there is still varying output depending on the background run,
so I've attached output from two runs in the background.

cheers,
Pádraig

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