When building the documentation/javadoc module, Maven executes the javadoc plugin on each submodules.

If one of the build fails for a submodule (you have a BUILD FAILURE in one of the files in target/invoker/), the global build doesn't fail. Thus we completely ignore Javadoc errors in our usual CI builds.

Executing the -release job triggers the error as the -performRelease option triggers the javadoc build for each submodule, thus the build fails if there is a Javadoc error.