bug#31287: qemu-minimal-2.10.2 fails to build

[Mark H Weaver <mhw@netris.org>]

Hi Diego,

Diego Nicola Barbato <dnbarbato@posteo.de> writes:
> I am closing this as I can no longer reproduce this error.  It failed a
> couple of times in a row but after rebooting (I did not run `guix pull'
> so I am still on the same commit) the build succeeds every time.
>
> Sorry for the noise

No worries, it's not noise at all.  Thanks for the report!

On hydra.gnu.org, I occasionally see non-deterministic test failures
occur during qemu's test suite.  Judging from my archive of failed build
logs from hydra, it seems to happen about 10 times per year.

The precise details of which test failed would have been higher up in
the build log, and was not in the excerpt included in your bug report,
but I have complete build logs for several similar failures that could
be analyzed, if someone wants to investigate further.

The two most recent failures of qemu-minimal from hydra that I have logs
for occurred while building for i686-linux, and both on the same test.

Here's the relevant excerpt of the most recent one, which happened in
January 2018:

--8<---------------cut here---------------start------------->8---
TEST: tests/vhost-user-test... (pid=17078)
  /x86_64/vhost-user/read-guest-mem:                                   OK
  /x86_64/vhost-user/migrate:                                          OK
  /x86_64/vhost-user/multiqueue:                                       OK
  /x86_64/vhost-user/reconnect:                                        OK
  /x86_64/vhost-user/connect-fail:                                     OK
  /x86_64/vhost-user/flags-mismatch:                                   **
ERROR:tests/vhost-user-test.c:835:test_flags_mismatch: child process (/x86_64/vhost-user/flags-mismatch/subprocess [17117]) failed unexpectedly
FAIL
GTester: last random seed: R02S1d5712e1b6c2bad14ccfb03776ee527f
(pid=17129)
FAIL: tests/vhost-user-test
--8<---------------cut here---------------end--------------->8---

and here's the previous one, from October 2017:

--8<---------------cut here---------------start------------->8---
TEST: tests/vhost-user-test... (pid=15318)
  /i386/vhost-user/read-guest-mem:                                     OK
  /i386/vhost-user/migrate:                                            OK
  /i386/vhost-user/multiqueue:                                         OK
  /i386/vhost-user/reconnect:                                          OK
  /i386/vhost-user/connect-fail:                                       **
ERROR:tests/vhost-user-test.c:807:test_connect_fail: child process (/i386/vhost-user/connect-fail/subprocess [15346]) failed unexpectedly
FAIL
GTester: last random seed: R02S8ba3c1324b4ca498e277141dad6cae34
(pid=15357)
  /i386/vhost-user/flags-mismatch:                                     OK
FAIL: tests/vhost-user-test
--8<---------------cut here---------------end--------------->8---

I can send the full logs upon request.

       Mark