message: pipeline: Avoid Twine
  For some reason, Twine(int), when concatenated, may incorrectly become Twine(const unsigned long&) and cause a dereference crash.
diff: @@ -377,7 +377,7 @@ bool indexer_Parse(SemaManager *completion, WorkingFiles *wfiles,
  SmallString<256> msg;
  (Twine(deleted ? "delete " : "parse ") + path_to_index).toVector(msg);
  if (n_errs)
  - msg += (" error:" + Twine(n_errs) + " " + first_error).toStringRef(tmp);
  + msg += " error:" + std::to_string(n_errs) + ' ' + first_error;
  if (LOG_V_ENABLED(1)) {
  msg += "\n ";
  for (const char *arg : entry.args)
  