[cfe-dev] RFC: Promote AArch64 to be built by default

[Tim Northover]

> I think this is the right thing to do. Once you've resolved the Mac and Windows issues, go for it.

Thanks Doub. Just to let people know what happened. I enabled in
r174322 around lunchtime. Here's a report of the noticed failures with
status (important/outstanding ones at the top). Feel free to do
anything from telling me about more problems to reverting the patch
when llvm.org comes up.

http://lab.llvm.org:8011/builders/clang-x86_64-ubuntu-gdb-75/builds/1892:
    Didn't rerun configure. If anyone has access to this, forcing it
would be very helpful.
Shared library builds on OSX fail (cyclic dependency):
    I hope to post a patch this evening.
http://lab.llvm.org:8011/builders/clang-x86_64-darwin11-self-mingw32/builds/9058
    There are warnings in AArch64 code. I'll fix them tomorrow. There
may be more warnings not yet noticed, I've been fighting actual
failures today.

The rest are believed resolved:

http://lab.llvm.org:8011/builders/clang-x86_64-darwin11-self-mingw32/builds/9057:
    Improper 33-bit integer constant. Fixed in r174324.
http://bb.pgr.jp/builders/cmake-clang-i686-msvc10/builds/1850
    Improper use of StringRef causing errors when compiler is MSVC
(fixed in r174328)
http://bb.pgr.jp/builders/clang-i686-msys/builds/409:
    llvm-config reported an error, believed to be the result of
incomplete configure step. 410 succeeded.
http://lab.llvm.org:8011/builders/llvm-mips-linux/builds/862:
    Semi-regular timeout?

Cheers.

Tim.