[PATCH] Add CMake option LLVM_USE_SANITIZER to allow bootstrap of LLVM/Clang under ASan/MSan.

[Michael Spencer]

  This change has a lot of other changes mixed in to it. Please split those changes out to another patch.

  As for the sanitizer changes, they seem fine, but they also seem Linux specific. There's also not an option for ubsan, which can be on at the same time as others.

http://llvm-reviews.chandlerc.com/D459

BRANCH
  svn

ARCANIST PROJECT
  llvm