[clang] [clang][clang-cl] Add -fms-preprocessor-compat and support /Zc:preprocessor (PR #167200)

[Josh Dowell via cfe-commits]

================
@@ -375,6 +375,12 @@
 // RUN: %clang_cl -c -### /std:clatest -- %s 2>&1 | FileCheck -check-prefix CHECK-CLATEST %s
 // CHECK-CLATEST: -std=c23
 
+// RUN: %clang_cl -c -### /Zc:preprocessor- -- %s 2>&1 | FileCheck -check-prefix CHECK-ZC-PREPROCESSOR-NO %s
+// CHECK-ZC-PREPROCESSOR-NO: -fms-preprocessor-compat
+
+// RUN: %clang_cl -c -### /Zc:preprocessor -- %s 2>&1 | FileCheck -check-prefix CHECK-ZC-PREPROCESSOR %s
+// CHECK-ZC-PREPROCESSOR-NOT: -fms-preprocessor-compat
----------------
Slartibarty wrote:

Swapped it over your suggestion, thanks

https://github.com/llvm/llvm-project/pull/167200