diff -ruN ../at-3.1.8.orig/parsetime.y ./parsetime.y
--- ../at-3.1.8.orig/parsetime.y	Mon Jan 14 17:59:09 2002
+++ ./parsetime.y	Mon Jan 14 18:01:22 2002
@@ -193,7 +193,6 @@
 				    exectm.tm_year -= 1900;
 				}
 
-				free ($1);
 			}
 			else {
 			    sscanf($1, "%d", &exectm.tm_hour);
@@ -369,6 +368,8 @@
     time_only = 0;
     if (yyparse() == 0) {
 	exectime = mktime(&exectm);
+	if (exectime == (time_t)-1)
+		return 0;
 	if (isgmt) {
 	    exectime += timezone;
 	    if (daylight) {
@@ -432,6 +433,8 @@
 {
     time_t timeval;
     timeval = mktime(tm);
+    if (timeval == (time_t)-1)
+	timeval = (time_t)0;
     timeval += numsec;
     *tm = *localtime(&timeval);
 }