message: Fix GetCallersForAllBaseFunctions found by romix
diff: @@ -274,11 +274,12 @@ std::vector<Use> GetCallersForAllBaseFunctions(QueryDatabase* db,
  queue.pop();
  AddRange(&callers, func.uses);
  - if (def)
  - EachWithGen<QueryFunc>(db->funcs, def->base, [&](QueryFunc& func1) {
  + if (const QueryFunc::Def* def1 = func.AnyDef()) {
  + EachWithGen<QueryFunc>(db->funcs, def1->base, [&](QueryFunc& func1) {
  queue.push(&func1);
  });
  }
  + }
  return callers;
  }
  