prevent seg

git-svn-id: http://svn.freeswitch.org/svn/freeswitch/trunk@10296 d0543943-73ff-0310-b7d9-9358b9ac24b2

src/switch_core_session.c

@@ -86,7 +86,7 @@ SWITCH_DECLARE(void) switch_core_session_hupall_matching_var(const char *var_nam
 			const char *this_val;
 			session = (switch_core_session_t *) val;
 			switch_core_session_read_lock(session);
-			if ((this_val = switch_channel_get_variable(session->channel, var_name)) && (!strcmp(this_val, var_val))) {
+			if ((this_val = switch_channel_get_variable(session->channel, var_name)) && && var_val && (!strcmp(this_val, var_val))) {
 				switch_channel_hangup(switch_core_session_get_channel(session), cause);
 			}
 			switch_core_session_rwunlock(session);