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

[Tim Northover]

> http://bb.pgr.jp/builders/cmake-clang-i686-msvc10/builds/1850
>     Improper use of StringRef causing errors when compiler is MSVC
> (fixed in r174328)

Just a note that I think this is also responsible for:
    http://lab.llvm.org:8011/builders/llvm-x86_64-linux-vg_leak/builds/279

Tim.