[clang] [clang] Stub out gcc_struct attribute (PR #71148)

[Fangrui Song via cfe-commits]

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@@ -4393,15 +4393,15 @@ def : Joined<["-"], "mmacosx-version-min=">,
   Group<m_Group>, Alias<mmacos_version_min_EQ>;
 def mms_bitfields : Flag<["-"], "mms-bitfields">, Group<m_Group>,
   Visibility<[ClangOption, CC1Option]>,
-  HelpText<"Set the default structure layout to be compatible with the Microsoft compiler standard">,
-  MarshallingInfoFlag<LangOpts<"MSBitfields">>;
+  HelpText<"Set the default structure layout to be compatible with the Microsoft compiler standard">;
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MaskRay wrote:

The Driver and Frontend changes seem unneeded? `-mno-ms-bitfields` can remain a driver-only option that is not in CC1.

https://github.com/llvm/llvm-project/pull/71148