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Implement test coverage for Lix's native code #1186

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opened 2026-04-19 17:58:33 +00:00 by jade · 1 comment
jade commented 2026-04-19 17:58:33 +00:00
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It would be very valuable to know which code paths are entirely uncovered by any tests. We apparently lost the ability to do coverage when we rewrote the build, but we can build something better than we had before, by using llvm's native coverage system rather than gcov. This can then be used for coverage guided fuzzing infra in the future.

We can do this with llvm's coverage system: https://clang.llvm.org/docs/SourceBasedCodeCoverage.html

I'm hacking on this today.

It would be very valuable to know which code paths are entirely uncovered by any tests. We apparently lost the ability to do coverage when we rewrote the build, *but* we can build something better than we had before, by using llvm's native coverage system rather than gcov. This can then be used for coverage guided fuzzing infra in the future. We can do this with llvm's coverage system: https://clang.llvm.org/docs/SourceBasedCodeCoverage.html I'm hacking on this today.
jade self-assigned this 2026-04-19 17:58:33 +00:00
jade changed title from Implement test coverage for Lix to Implement test coverage for Lix's native code 2026-04-19 17:58:40 +00:00
lix-bot commented 2026-04-19 22:17:17 +00:00
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This issue was mentioned on Gerrit on the following CLs:

  • commit message in cl/5489 ("Test coverage for native code WIP")
<!-- GERRIT_LINKBOT: {"cls": [{"backlink": "https://gerrit.lix.systems/c/lix/+/5489", "number": 5489, "kind": "commit message"}], "cl_meta": {"5489": {"change_title": "Test coverage for native code WIP"}}} --> This issue was mentioned on Gerrit on the following CLs: * commit message in [cl/5489](https://gerrit.lix.systems/c/lix/+/5489) ("Test coverage for native code WIP")
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make lix go faster

  
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lix-project/lix#1186
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