[s390x] testsuite fails on Fedora 36

[juhp]

Not sure what changed but the zlib-0.6.2.3 testsuite started failing on Fedora Linux 36 s390x:

  unit tests
    simple gzip case:                                 OK
    detect bad crc:                                   OK
    detect non-gzip:                                  FAIL
      test/Test.hs:193:
      expected: "invalid code lengths set"
       but got: "Operation-Ending-Supplemental Code is 0x27"

It is working normally elsewhere (x86_64, i686, aarch64, armv7hl, ppc64le).
https://koji.fedoraproject.org/koji/taskinfo?taskID=83592764

Downstream bug: https://bugzilla.redhat.com/show_bug.cgi?id=2045430 with a copy of the tail of the build.log

The version of the C zlib in Fedora or the package has not changed.

[Bodigrim]

Not sure what changed

I assume your build server has been upgraded to z15, with a new DFLTCC instruction. zlib has a code path, engaging DFLTCC when available, see the patch. Error code 27 stands for "a code which is in the sequence of codes specifying code lengths for literal bytes, and the code does not match any of the codes determined to represent the set of referenced code lengths, as specified earlier in the compressed DHT" (http://publibfp.dhe.ibm.com/epubs/pdf/a227832c.pdf, page 26-37), so it is morally equivalent to expected "invalid code lengths set".

We can amend test suite to cover both possible error messages, but in general this should not be a blocker.

[Bodigrim]

@juhp could you please check whether master branch works fine now?

[juhp]

Brilliant, thank you! You never fail to impress!!

I built current head 670fe89
https://koji.fedoraproject.org/koji/taskinfo?taskID=84021651
and yes, now the testsuite passes on s390x
https://kojipkgs.fedoraproject.org/work/tasks/1656/84021656/build.log