[clang] [flang] [flang] Add MSC_VER and target arch defines when targeting the MSVC ABI (PR #73250)

[Brad King via cfe-commits]

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@@ -322,6 +345,7 @@ void Flang::addTargetOptions(const ArgList &Args,
 
   if (Triple.isKnownWindowsMSVCEnvironment()) {
     processVSRuntimeLibrary(TC, Args, CmdArgs);
+    addVSDefines(TC, Args, CmdArgs);
   }
 
   // TODO: Add target specific flags, ABI, mtune option etc.
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bradking wrote:

OTOH this could be considered out of scope for this PR.


https://github.com/llvm/llvm-project/pull/73250