+#ifdef LISP_FEATURE_WIN32
+ /* No _r versions on Windows, but the API documentation also
+ * doesn't warn them about being non-reentrant... So here's
+ * hoping they actually are -- once Windows grows threads
+ * this better be checked, though.
+ *
+ * The Windows versions also don't support times before the
+ * epoch, so we kludge it. */
+ if (when < 0)
+ when = 0;