diff --git a/contrib/pg_upgrade/parallel.c b/contrib/pg_upgrade/parallel.c
index bf52890ad4..caeebcd9d0 100644
--- a/contrib/pg_upgrade/parallel.c
+++ b/contrib/pg_upgrade/parallel.c
@@ -32,18 +32,18 @@ HANDLE	   *thread_handles;
 
 typedef struct
 {
-	char		log_file[MAXPGPATH];
-	char		opt_log_file[MAXPGPATH];
-	char		cmd[MAX_STRING];
+	char	   *log_file;
+	char	   *opt_log_file;
+	char	   *cmd;
 } exec_thread_arg;
 
 typedef struct
 {
 	DbInfoArr  *old_db_arr;
 	DbInfoArr  *new_db_arr;
-	char		old_pgdata[MAXPGPATH];
-	char		new_pgdata[MAXPGPATH];
-	char		old_tablespace[MAXPGPATH];
+	char	   *old_pgdata;
+	char	   *new_pgdata;
+	char	   *old_tablespace;
 } transfer_thread_arg;
 
 exec_thread_arg **exec_thread_args;
@@ -113,10 +113,12 @@ parallel_exec_prog(const char *log_file, const char *opt_log_file,
 			pg_log(PG_FATAL, "could not create worker process: %s\n", strerror(errno));
 #else
 		if (thread_handles == NULL)
+			thread_handles = pg_malloc(user_opts.jobs * sizeof(HANDLE));
+
+		if (exec_thread_args == NULL)
 		{
 			int			i;
 
-			thread_handles = pg_malloc(user_opts.jobs * sizeof(HANDLE));
 			exec_thread_args = pg_malloc(user_opts.jobs * sizeof(exec_thread_arg *));
 
 			/*
@@ -125,16 +127,22 @@ parallel_exec_prog(const char *log_file, const char *opt_log_file,
 			 * thread different from the one that allocated it.
 			 */
 			for (i = 0; i < user_opts.jobs; i++)
-				exec_thread_args[i] = pg_malloc(sizeof(exec_thread_arg));
+				exec_thread_args[i] = pg_malloc0(sizeof(exec_thread_arg));
 		}
 
 		/* use first empty array element */
 		new_arg = exec_thread_args[parallel_jobs - 1];
 
 		/* Can only pass one pointer into the function, so use a struct */
-		strcpy(new_arg->log_file, log_file);
-		strcpy(new_arg->opt_log_file, opt_log_file);
-		strcpy(new_arg->cmd, cmd);
+		if (new_arg->log_file)
+			pg_free(new_arg->log_file);
+		new_arg->log_file = pg_strdup(log_file);
+		if (new_arg->opt_log_file)
+			pg_free(new_arg->opt_log_file);
+		new_arg->opt_log_file = opt_log_file ? pg_strdup(opt_log_file) : NULL;
+		if (new_arg->cmd)
+			pg_free(new_arg->cmd);
+		new_arg->cmd = pg_strdup(cmd);
 
 		child = (HANDLE) _beginthreadex(NULL, 0, (void *) win32_exec_prog,
 										new_arg, 0, NULL);
@@ -219,10 +227,12 @@ parallel_transfer_all_new_dbs(DbInfoArr *old_db_arr, DbInfoArr *new_db_arr,
 			pg_log(PG_FATAL, "could not create worker process: %s\n", strerror(errno));
 #else
 		if (thread_handles == NULL)
+			thread_handles = pg_malloc(user_opts.jobs * sizeof(HANDLE));
+
+		if (transfer_thread_args == NULL)
 		{
 			int			i;
 
-			thread_handles = pg_malloc(user_opts.jobs * sizeof(HANDLE));
 			transfer_thread_args = pg_malloc(user_opts.jobs * sizeof(transfer_thread_arg *));
 
 			/*
@@ -231,7 +241,7 @@ parallel_transfer_all_new_dbs(DbInfoArr *old_db_arr, DbInfoArr *new_db_arr,
 			 * thread different from the one that allocated it.
 			 */
 			for (i = 0; i < user_opts.jobs; i++)
-				transfer_thread_args[i] = pg_malloc(sizeof(transfer_thread_arg));
+				transfer_thread_args[i] = pg_malloc0(sizeof(transfer_thread_arg));
 		}
 
 		/* use first empty array element */
@@ -240,9 +250,15 @@ parallel_transfer_all_new_dbs(DbInfoArr *old_db_arr, DbInfoArr *new_db_arr,
 		/* Can only pass one pointer into the function, so use a struct */
 		new_arg->old_db_arr = old_db_arr;
 		new_arg->new_db_arr = new_db_arr;
-		strcpy(new_arg->old_pgdata, old_pgdata);
-		strcpy(new_arg->new_pgdata, new_pgdata);
-		strcpy(new_arg->old_tablespace, old_tablespace);
+		if (new_arg->old_pgdata)
+			pg_free(new_arg->old_pgdata);
+		new_arg->old_pgdata = pg_strdup(old_pgdata);
+		if (new_arg->new_pgdata)
+			pg_free(new_arg->new_pgdata);
+		new_arg->new_pgdata = pg_strdup(new_pgdata);
+		if (new_arg->old_tablespace)
+			pg_free(new_arg->old_tablespace);
+		new_arg->old_tablespace = old_tablespace ? pg_strdup(old_tablespace) : NULL;
 
 		child = (HANDLE) _beginthreadex(NULL, 0, (void *) win32_transfer_all_new_dbs,
 										new_arg, 0, NULL);
diff --git a/contrib/pg_upgrade/test.sh b/contrib/pg_upgrade/test.sh
index e1db376155..30bc527431 100644
--- a/contrib/pg_upgrade/test.sh
+++ b/contrib/pg_upgrade/test.sh
@@ -152,7 +152,7 @@ PGDATA=$BASE_PGDATA
 
 initdb -N
 
-pg_upgrade -d "${PGDATA}.old" -D "${PGDATA}" -b "$oldbindir" -B "$bindir" -p "$PGPORT" -P "$PGPORT"
+pg_upgrade $PG_UPGRADE_OPTS -d "${PGDATA}.old" -D "${PGDATA}" -b "$oldbindir" -B "$bindir" -p "$PGPORT" -P "$PGPORT"
 
 pg_ctl start -l "$logdir/postmaster2.log" -o "$POSTMASTER_OPTS" -w