[clang] [clang][DependencyScanning] Add a Clang Driver Option to Enable Dependency Scanning Logging (PR #211966)

[Jan Svoboda via cfe-commits]

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@@ -125,6 +127,9 @@ buildCompilation(ArrayRef<std::string> ArgStrs, DiagnosticsEngine &Diags,
     return std::make_pair(nullptr, nullptr);
   }
 
+  Logger.enable(
+      Compilation->getArgs().getLastArgValue(options::OPT_fdepscan_log_path));
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jansvoboda11 wrote:

It's fairly unusual for driver arguments to exist solely to change the scanner's behavior. What's the use-case here?

https://github.com/llvm/llvm-project/pull/211966