[llvm] [llvm-pdbutil] Create public symbols in yaml2pdb (PR #157362)

[via llvm-commits]

================
@@ -880,6 +883,23 @@ static void yamlToPdb(StringRef Path) {
     IpiBuilder.addTypeRecord(Type.RecordData, std::nullopt);
   }
 
+  auto &GsiBuilder = Builder.getGsiBuilder();
+  const auto &Publics = YamlObj.PublicsStream.value_or(DefaultPublicsStream);
----------------
Nerixyz wrote:

Maybe I'm missing something here, but doesn't the `const auto&` bind to a temporary? Because `YamlObj.PublicsStream` is a `std::optional<PdbPublicsStream>`, then the return of `value_or` is a `PdbPublicsStream`.

The other streams above also do this, and I'd guess this would break in some way if it would bind to a temporary.

https://github.com/llvm/llvm-project/pull/157362