CodeQL causes qmake to segfault when building C++ project

[dail8859]

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I'm attempting to add CodeQL to my C++ Qt project. dail8859/NotepadNext#445

It is set for analyzing "python" and "cpp". The job to analyze python builds the C++ application and works correctly, however when analyzing cpp it attempts to run the exact same qmake command to build the application but fails:

/home/runner/work/_temp/0b34b594-7731-4bfe-b5d8-6142839a8614.sh: line 4: 8801 Segmentation fault (core dumped) qmake NotepadNext.pro

The weird thing is there is no differences in the python or cpp jobs (no conditional steps). So my only conclusion is github/codeql-action/init@v2 is doing something odd behind the scenes when the language is set to cpp.

Has anyone else ran across something like this?

[aibaars]

I've never seen that happen before. Could you re-run the failed job and enable debug logging? That should cause the codeql-action to upload a debug artifact. Hopefully the detailed logs (especially build-tracer.log) help explain what is going wrong.

See also: https://github.blog/changelog/2022-05-24-github-actions-re-run-jobs-with-debug-logging/

[dail8859]

Dug through the logs but didn't see anything obvious myself :(

[aibaars]

I didn't see anything obvious myself either :( .

[aeisenberg]

This is some strange stuff. I have a few suggestions, but nothing seems like an obvious fix:

1. Your codeql workflow file does a lot of extra work between the initialization and analysis phase. Normally, this shouldn't be a problem, but every call is monitored by the codeql tracer (which is the parent process that helps build the codeql database). Can you try moving all of the non-build steps before the codeql-action/init init step? So, this would mean moving jurplel/install-qt-action and splitting the next run step so that the apt-get calls are performed earlier. It may be that these steps are interfering with the tracer.
2. Try calling qmake with the same arguments as in the build.yml workflow.
3. I don't see any actions debugging information. Can you try re-running the workflow with the debug box selected?

[dail8859]

@aeisenberg Thanks for these suggestions! I had originally stuck close to the build.yml file but started to try different things to see if it was related to something I was doing. I also previously tried the specific version of Ubuntu that the build.yml is using and still the same results.

I made the suggested changes, but cpp still fails. I enabled debugging as well so there is an artifact attached.

https://github.com/dail8859/NotepadNext/actions/runs/6302919787

[aeisenberg]

Thanks for trying this out. I'll see if someone with more experience on the tracer has some thoughts.

[trevorsandy]

After upgrading my code base from Qt 5.15.2 to Qt 6.9.1, my C++ GitHub build is experiencing the behaviour described in this ticket.

+ qmake6 -nocache CONFIG+=release CONFIG-=debug_and_release CONFIG+=deb LPub3D.pro
builds/utilities/ci/github/linux-compile.sh: line 311: 13670 Segmentation fault      (core dumped) ${QMAKE_EXEC} -nocache CONFIG+=release CONFIG-=debug_and_release CONFIG+=${distropkg} LPub3D.pro

It's quite strange as qmake6 runs successfully in the job's 'Renderer' step but consistently fails with a segmentation fault in the cpp-language 'Compile' step.

I've re-run the job with debug logging but I did not find any meaningful information in the expanded build log.

You can analyze the build log here:

Cheers,

[aeisenberg]

Can you please raise an issue in https://github.com/github/codeql/issues/new? Our first responder will be able to help you out.

[trevorsandy]

Very well - thank you for your assistance.

Cheers,