As I noted before, the ‘clean build’ option was not set in the Octave build, setting this option and resolving the errors caused by it – I had manually copied groff.enc into the build tree, which now needs to be done automatically – makes the build work. This brings up a couple of points, it seems that the Jenkins default configuration for ‘freestyle’ projects is not to clean when launching a new build. I will need to check the other projects to make sure they are set to clean too. It also makes me think that Jenkins ‘freestyle’ build configurations are not under change control. The way to resolve this is to have a build script which is under change control and call that and only that from the Jenkins build. I don’t think what I am doing here is significant enough to warrant that, so I will leave my configuration as is, but it is something to think about on more complex configurations.