CGBuiltin.cpp: Fix abuse of ArrayRef in EmitOverflowIntrinsic().

In ArrayRef<T>(X), X should not be temporary value. It could be rewritten more redundantly;

  llvm::Type *XTy = X->getType();
  ArrayRef<llvm::Type *> Ty(XTy);
  llvm::Value *Callee = CGF.CGM.getIntrinsic(IntrinsicID, Ty);

Since it is safe if both XTy and Ty are temporary value in one statement, it could be shorten;

  llvm::Value *Callee = CGF.CGM.getIntrinsic(IntrinsicID, ArrayRef<llvm::Type*>(X->getType()));

ArrayRef<T> has an implicit constructor to create uni-entry of T;

  llvm::Value *Callee = CGF.CGM.getIntrinsic(IntrinsicID, X->getType());

MSVC-generated clang.exe crashed.

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@172352 91177308-0d34-0410-b5e6-96231b3b80d8
Refactor the x86 CPU name logic in the driver and pass -march and -mcpu
flag information down from the Clang driver into the Gold linker plugin
for LTO. This allows specifying -march on the linker commandline and
should hopefully have it pass all the way through to the LTO optimizer.

Fixes PR14697.

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@172354 91177308-0d34-0410-b5e6-96231b3b80d8