[clang] [clang][modules] Print library module manifest path. (PR #76451)

[Mark de Wever via cfe-commits]

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@@ -2164,6 +2164,12 @@ bool Driver::HandleImmediateArgs(const Compilation &C) {
     return false;
   }
 
+  if (C.getArgs().hasArg(options::OPT_print_library_module_manifest_path)) {
+    llvm::outs() << "module: ="
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mordante wrote:

returning an empty string gives an empty output. This feels wrong, returning an error value indicates the tool has done something with the request. No output may mean the request has been ignored.

https://github.com/llvm/llvm-project/pull/76451