r222906 - Create a new 'flag_enum' attribute.

[Sean Hunt]

On Thu, Nov 27, 2014 at 7:53 PM, Sean Hunt <scshunt at csclub.uwaterloo.ca> wrote:
> Author: coppro
> Date: Thu Nov 27 18:53:20 2014
> New Revision: 222906
>
> URL: http://llvm.org/viewvc/llvm-project?rev=222906&view=rev
> Log:
> Create a new 'flag_enum' attribute.
>
> This attribute serves as a hint to improve warnings about the ranges of
> enumerators used as flag types. It currently has no working C++ implementation
> due to different semantics for enums in C++. For more explanation, see the docs
> and testcases.
>
> Reviewed by Aaron Ballman.

After some discussion with dgregor, I've started work on a patch to
fix a few issues identified with this. Unfortunately, though, I don't
have the time to do this in time for 3.6. Can this please be reverted
on the 3.6 branch?

Sean