Handling C++11

[Rainer Müller]

On 2017-01-16 21:03, Ken Cunningham wrote:
> Rather than force the older systems to install gcc6 and libgcc and
> then find a roundabout and complicated way to support cxx11 with c++
> standard library inconsistencies, I would suggest we finally just
> change/add/modify/get the buildbots to libc++ once and for all and be
> done with that.

The main problem with this would be the upgrade path for existing
installations.

1) Store cxx_stdlib per port in registry. With this, existing
   installations can be marked as outdated when the global setting
   is changed.

2) Honor cxx_stdlib in selection of archive_sites
   (similar to applications_dir and frameworks_dir)

3) Release base with changed defaults

4) Configure buildbots with libc++, publish binary archives in
   different directory and configure that for archive_sites in the
   ports tree.

Rainer