From a5fdf6ba8a344db456b8dd4d52f50ff5caefb2df Mon Sep 17 00:00:00 2001
From: Nikolaj Bjorner <nbjorner@microsoft.com>
Date: Tue, 16 Nov 2021 09:54:06 -0800
Subject: [PATCH] Update viable2.cpp

---
 src/math/polysat/viable2.cpp | 5 +++++
 1 file changed, 5 insertions(+)

diff --git a/src/math/polysat/viable2.cpp b/src/math/polysat/viable2.cpp
index 67d7b853b..f6d625671 100644
--- a/src/math/polysat/viable2.cpp
+++ b/src/math/polysat/viable2.cpp
@@ -72,6 +72,11 @@ namespace polysat {
         if (e && e->interval.is_full())
             return;
 
+        if (ne->interval.is_currently_empty()) {
+            m_alloc.push_back(ne);
+            return;
+        }
+
         auto create_entry = [&]() {
             m_trail.push_back({ v, ne });
             s.m_trail.push_back(trail_instr_t::viable_add_i);