It doesn't look like just vim - it looks like exiftool, graphite2,

cups-filters, gvim, and imagemagick all are blocking.

I'd guess that these packages need a version bump or you need to unmask
one of the newer builds (most likely they haven't been stabilized yet.)

Agree - my amd64 system upgraded perl to 5.22 on Friday, so re-sync, and try again. Also to help resolve upgrade issues i firstly add --deep to emerge's switches and if that doesnt help, bump up --backtrack=