From 80d5d661589e6283b5df3a8fd34f2c1eaad7f353 Mon Sep 17 00:00:00 2001
From: Nikolaj Bjorner <nbjorner@microsoft.com>
Date: Thu, 4 Jun 2020 01:12:04 -0700
Subject: [PATCH] handling cancelation #4425

Signed-off-by: Nikolaj Bjorner <nbjorner@microsoft.com>
---
 src/tactic/tactic.cpp | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/src/tactic/tactic.cpp b/src/tactic/tactic.cpp
index dd248bcca..66f58f71e 100644
--- a/src/tactic/tactic.cpp
+++ b/src/tactic/tactic.cpp
@@ -190,6 +190,10 @@ lbool check_sat(tactic & t, goal_ref & g, model_ref & md, labels_vec & labels, p
             (*mc)(labels);
             model_converter2model(m, mc.get(), md);
         }
+        if (!m.inc()) {
+            reason_unknown = "canceled";
+            return l_undef;
+        }
         if (!md) {
             // create empty model.
             md = alloc(model, m);