"The -frepo won't expand templated friend functions!"
This is a known bug; currently you'll have to explicitly instantiate
friend functions when using -frepo due to this bug (in 2.7.0
through 2.7.2 at least).
With earlier versions of the repo patch, there was a bug that happens when you have given a quoted command line switch, something like
-D'MESSAGE="hello there"'
The repo code tries to recompile files using the same flags you originally specified, but doesn't quote arguments that need quoting, resulting in failures in some cases. This is no longer a problem with the 2.7.2 patch.