[PATCH] D28383: build: add a heuristic to determine the C++ ABI

[Shoaib Meenai via Phabricator via cfe-commits]

smeenai added a comment.

In https://reviews.llvm.org/D28383#637570, @majnemer wrote:

> Why isn't this equivalent to `_MSC_VER` ?


You can have scenarios where you're targeting the Itanium ABI but still have `_MSC_VER` defined, e.g.

  % clang -target i686-windows-itanium -fmsc-version=1900 -E -dM - < /dev/null | grep _MSC_VER
  #define _MSC_VER 1900


Repository:
  rL LLVM

https://reviews.llvm.org/D28383