macdeployqt does not copy frameworks already linked as @rpath

If a Qt framework is linked into an executable in 5.5 it gets linked in using the @rpath mechanism (as shown by otool -L immediately after linking).

If macdeployqt is used to deploy, it does not copy (to the bundle) any Qt framework that is already linked as @rpath. This makes macdeployqt fail to perform its most basic job.

If I modify the executable with install_name_tool -change @rpath... etc. to a hardcoded path; then run macdeployqt, it works fine (i.e. copies the Qt files to the bundle).