I was excited to see Bilal’s announcement of goblint, and I’ve spent the past week getting Crosswords to work with it. This is a tool I’ve always wanted and I’m pretty convinced it will be a great boon for the GNOME ecosystem. I’m posting my notes in hope that more people try it out:

• First and most importantly, Bilal has been so great to work with. I have filed ~20 issues and feature requests and he fixed them all very quickly. In some cases, he fixed the underlying issue before I completed adding annotations to the code.
• Most of the issues flagged were idiomatic and stylistic, but it did find real bugs. It found a half-dozen leaks, a missing g_timeout removal, and five missing class function chain ups. One was a long-standing crasher. There’s a definite improvement in quality from adopting this tool.
• I’m also excited about pairing this with new GSoC interns. The types of things goblint flags are the things that students hit in particular (when they don’t write it all their code with AI). I think goblint will be even more important to our ecosystem as a teaching tool to our C codebase. It’s already effectively replaced my styleguide.
• In a few instances, the use_g_autoptr rule outstripped static-scan’s ability to track leaks. Ultimately, I ended up annotating and removing the g_autoptr() calls as I couldn’t get the two to play nicely together.
• Along the same lines, cairo, pango, and librsvg all lack G_DEFINE_AUTOPTR_CLEANUP_FUNC . It would be really great if we could fix these core libraries. In the meantime, you can add the following to your project’s goblint.toml file:

[rules.use_g_autoptr_inline_cleanup]
level = "error"
ignore_types = ["cairo_*", "Pango*", "RsvgHandle"]

• I had some trouble getting the pipeline integrated with GNOME’s gitlab. The gitlab recipe on his page uses premium features unavailable in the self hosted version. If it’s helpful for others, here’s what I ended up using:

goblint:
  stage: analysis
  extends:
    - "opensuse-container@x86_64.stable"
    - ".fdo.distribution-image@opensuse"
  needs:
    - job: opensuse-container@x86_64.stable
      artifacts: false
  before_script:
    - source ci/env.sh
    - cargo install --git https://github.com/bilelmoussaoui/goblint goblint
  script:
    # Goblint is fast. We run it twice: Once to generate the report,
    # and a second time to display the output and triger an error
    - /root/.cargo/bin/goblint . --format sarif > goblint.sarif || true
    - /root/.cargo/bin/goblint . --format text
  artifacts:
    reports:
      sast: goblint.sarif
    when: always

YMMV