[clang] [flang][driver] Mark -fcommon and -mtune as visible in Flang (PR #68657)

[Andrzej Warzyński via cfe-commits]

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@@ -5077,6 +5077,7 @@ def module_file_info : Flag<["-"], "module-file-info">, Flags<[NoXarchOption]>,
   HelpText<"Provide information about a particular module file">;
 def mthumb : Flag<["-"], "mthumb">, Group<m_Group>;
 def mtune_EQ : Joined<["-"], "mtune=">, Group<m_Group>,
+  Flags<[TargetSpecific]>, Visibility<[ClangOption, CLOption, DXCOption, FlangOption]>,
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banach-space wrote:

How did you infer these visibility flags? Also, could you add a test for this flag?

https://github.com/llvm/llvm-project/pull/68657