Handling C++11

[Marcus Calhoun-Lopez]

> On Jan 19, 2017, at 2:04 PM, Chris Jones <jonesc at hep.phy.cam.ac.uk> wrote:
> 
> I don't think we should, under any circumstances, but making the use of gcc to build c++ ports a standard practise.

Just to be clear, the proposal is not to use gcc but to use clang with libstdc++ and *only* on systems where it has been requested.
Your point, either way, remains valid.
However, I would argue that the proposal is not about changing any existing practices.
libc++ and clang would still, by far, be the best choices.
LibcxxOnOlderSystems would still be the recommendation for older system.
The proposal is only about attempting to respect what the user has requested.

-Marcus