As far as I can tell this was rejected we can see this from N3296: C++ FCD Comment Status Rev 6 which has the following comment:
Paper n2965 was largely rejected after the last CD on the grounds there was no associated national body comment, so I am submitting a national body comment this time.
and the disposition ended up being:
REJECTED
There is no consensus to adopt this proposal at this time
We can find a comment from Jonathan Wakely which points us to the gcc patches email about implementing N2965
into gcc and he notes that there is no TR2 anymore.
I don’t see any follow-up proposals for this