The clean up of SourceObjInfo requires iterating over each entry in a hashtable to its _ref member:

https://github.com/openjdk/jdk/blob/6475501a01268f5c35a9bf30f4104ce7a40d8181/src/hotspot/share/cds/archiveBuilder.hpp#L207-L213

class SrcObjTableCleaner {
public:
  bool do_entry(address key, const SourceObjInfo& value) {
    delete value.ref();
    return true;
  }
};

void ArchiveBuilder::clean_up_src_obj_table() {
  SrcObjTableCleaner cleaner;
  _src_obj_table.iterate(&cleaner);
}

This can be simplified by moving the "delete value.ref()" into the destructor of SourceObjInfo.