Since updating portage today (2016/05/01) I get the annoying message laymansync module's module_spec is old, missing attribute: 'sourcefile'. Backward compatibility may be removed in the future. File: /usr/lib64/python3.4/site-packages/portage/sync/modules/laymansync/__init__.py each time portage is "involved" I did re-emerge app-portage/layman-2.3.0-r1 but this did help.
There will be a layman release out very soon with this API change.
The release has been out and this bug slipped under my radar. Resolving it as fixed. :)