From aded8e5bf475b6a645488b67bc49d33fd5a7a2c4 Mon Sep 17 00:00:00 2001
From: Nikolaj Bjorner <nbjorner@microsoft.com>
Date: Mon, 12 Dec 2022 11:40:59 -0800
Subject: [PATCH] fix #6488

Signed-off-by: Nikolaj Bjorner <nbjorner@microsoft.com>
---
 src/ast/simplifiers/elim_unconstrained.cpp | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/src/ast/simplifiers/elim_unconstrained.cpp b/src/ast/simplifiers/elim_unconstrained.cpp
index b3f833a78..bb7a4fa49 100644
--- a/src/ast/simplifiers/elim_unconstrained.cpp
+++ b/src/ast/simplifiers/elim_unconstrained.cpp
@@ -205,7 +205,8 @@ void elim_unconstrained::freeze(expr* t) {
     if (!n.m_term)
         return;
     n.m_refcount = UINT_MAX / 2;
-    m_heap.increased(root(t));
+    if (m_heap.contains(root(t)))
+        m_heap.increased(root(t));
 }
 
 void elim_unconstrained::gc(expr* t) {