[llvm] r271468 - Add "REQUIRES-ANY" feature test

[Greg Parker via llvm-commits]

> On Jun 1, 2016, at 6:59 PM, Eric Fiselier via llvm-commits <llvm-commits at lists.llvm.org> wrote:
> 
> Author: ericwf
> Date: Wed Jun  1 20:59:57 2016
> New Revision: 271468
> 
> URL: http://llvm.org/viewvc/llvm-project?rev=271468&view=rev
> Log:
> Add "REQUIRES-ANY" feature test
> 
> Summary:
> This patch adds a "REQUIRES-ANY" feature test that is disjunctive. This marks a test as `UNSUPPORTED` if none of the specified features are available.
> 
> Libc++ has the need to write feature test such as `// REQUIRES-ANY: c++98, c++03`  when testing of behavior that is specific to older dialects but has since changed.

Eric, I'm finishing up a change which adds boolean expressions to lit (http://reviews.llvm.org/D18185). This would allow constraints like `REQUIRES: c++98 || c++03`.

Does libc++ use REQUIRES-ANY yet in its tests? I don't see anything in libcxx or libcxxabi trunk. I'm hoping that I can just delete the REQUIRES-ANY implementation.


-- 
Greg Parker     gparker at apple.com     Runtime Wrangler