Quo Vadis tr1?

[Ed Smith-Rowland]

All,

Apologies to whoever got this before, I meant to sent to libstdc++.
 From discussion of maths special functions issue PR83140;

> We could consider dropping the TR1 support, and just provide these
> functions for ISO/IEC 29124:2010 in C++11 (or later) and for C++17.
> But that decision should be taken separately, and should only happen
> on trunk anyway so we need to use _Tp(+1) here.

I am in favour of splitting new versions of the special functions out of tr1 and into std/bits.
I personally am itching to use at least C++11 for implementation.
We have been defaulting to C++11 for, IIRC, two releases (Hence my -Tp{+1} slip).
I have a lot of work towards this that I wanted to get into 9 anyway.

This would end the last useful thing in tr1 that's not better implemented elsewhere.
There are certainly people using tr1. Can we deprecate the whole namespace?
That might be too noisy.
I think we should be done with the special maths bugs in Bugzilla pretty soon.

Ed

Also, I think 83566 should go into tr1 first because it's not a
signature change.