Xpand builder deadlock situation

Today a colleague in my project came with an issue she experienced with several workspaces, which contain amongst others Xpand projects. After starting Eclipse during the initial build phase Eclipse hang and did nothing. In the workspace log we found indication for a deadlock situation, since there one of the last entries stated that thread Main was waiting for thread Main, and this happened during class loading of the XtendXpandBuilder. We debugged the situation and from the stacktraces of the running threads we could see that one thread tried to refresh a resource that was out of sync.

The problem was solved by starting Eclipse with the -refresh platform option. The out-of-sync resource was synchronized before the builder runs.