[clang] Reset CodeGenOptions fields for clean module/PCH builds (PR #138256)

[Michael Spencer via cfe-commits]

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@@ -209,20 +209,21 @@ void ModuleDepCollector::addOutputPaths(CowCompilerInvocation &CI,
 void dependencies::resetBenignCodeGenOptions(frontend::ActionKind ProgramAction,
                                              const LangOptions &LangOpts,
                                              CodeGenOptions &CGOpts) {
-  // TODO: Figure out better way to set options to their default value.
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Bigcheese wrote:

This comment is talking about setting it to the default value it would have if no argument is passed, which for these cases is empty, but not all options default to empty.

https://github.com/llvm/llvm-project/pull/138256