[clang] [Frontend][Sema] Add CC1-only -fms-anonymous-structs to enable Microsoft anonymous struct/union feature (PR #176551)

[Riyaz Ahmad via cfe-commits]

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@@ -25,6 +25,7 @@
 
 // This needs to exit non-0, for configure scripts.
 // RUN: not %clang /GR-
+// RUN: not %clang %s -fms-anonymous-structs -### 2>&1 | FileCheck %s --check-prefix=CL-MS-ERROR
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riyaz86a wrote:

removed this test.

https://github.com/llvm/llvm-project/pull/176551