From 73fa5995d40f6ebb6ab3b2cab4d59f577b5a0eb7 Mon Sep 17 00:00:00 2001
From: Nikolaj Bjorner <nbjorner@microsoft.com>
Date: Wed, 13 May 2020 19:35:17 -0700
Subject: [PATCH] fix #4316

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

diff --git a/src/sat/sat_solver.cpp b/src/sat/sat_solver.cpp
index 7336e12d3..6cc6cf6eb 100644
--- a/src/sat/sat_solver.cpp
+++ b/src/sat/sat_solver.cpp
@@ -1198,6 +1198,7 @@ namespace sat {
             return check_par(num_lits, lits);
         }
         flet<bool> _searching(m_searching, true);
+        m_clone = nullptr;
         if (m_mc.empty() && gparams::get_ref().get_bool("model_validate", false)) {
             m_clone = alloc(solver, m_params, m_rlimit);
             m_clone->copy(*this);