[clang] [clang][MBD] set up module build daemon infrastructure (PR #67562)

[Michael Spencer via cfe-commits]

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@@ -2836,6 +2836,18 @@ defm declspec : BoolOption<"f", "declspec",
   NegFlag<SetFalse, [], [ClangOption], "Disallow">,
   BothFlags<[], [ClangOption, CC1Option],
           " __declspec as a keyword">>, Group<f_clang_Group>;
+
+def fmodule_build_daemon : Flag<["-"], "fmodule-build-daemon">, Group<f_Group>,
+  Flags<[NoXarchOption]>,
+  Visibility<[ClangOption, CC1Option]>,
+  HelpText<"Enables module build daemon functionality">,
+  MarshallingInfoFlag<FrontendOpts<"ModuleBuildDaemon">>;
+def fmodule_build_daemon_EQ : Joined<["-"], "fmodule-build-daemon=">, Group<f_Group>,
+  Flags<[NoXarchOption]>,
+  Visibility<[ClangOption, CC1Option]>,
+  HelpText<"Enables module build daemon functionality and defines location of output files">,
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Bigcheese wrote:

I think this is less "output files" and more just the lock and log files.

https://github.com/llvm/llvm-project/pull/67562