Static Analysis for Gluster

04 Dec 2017 - gluster

Static analysis programs are quite useful, but also prone to false positives. It’s really hard to keep track of static analysis failures on a fairly large project. We’ve looked at several approaches in the past. The one that we used to do was to publish a report every day which people could look at if they wished. This guaranteed that nobody looked at it. Despite knowing where to look for it, even I barely looked at it.

The second approach was to run them twice, before your patch is merged and after your patch is merged in. If the count goes up with your patch, the test fails. This has a problem that it doesn’t account for false positives. An argument could be made that you could go fix another static analysis failure in your patch. But that means your patch now does two things, which isn’t fun for when you want to do a backport, for instance. Or even for history purposes. That’s landing two unrelated changes in one patch.

The approach that we’ve now gone with is to have them run on a nightly basis with Jenkins. Deepshika did almost all the work for this and wrote about it on her blog. It has more details on the actual implementation. This puts all the results in one place for everyone to take a look at. Jenkins also gives us a visual view of what changed over the course of time, which wasn’t as easy in the past.

She’s working on further improving the visual look by uniting all the jobs that are tied to static analysis. That way, we’ll have a nightly pipeline run for each branch that will put all the tests we care about for a particular branch in one place.