From 1ab7ab9d744d5cddec94ae539d4d52233fedcb16 Mon Sep 17 00:00:00 2001
From: Nikolaj Bjorner <nbjorner@microsoft.com>
Date: Thu, 23 Mar 2017 11:09:36 -0700
Subject: [PATCH] fix double ownership of enode marking causing crash during
 tracing. Issue #952

Signed-off-by: Nikolaj Bjorner <nbjorner@microsoft.com>
---
 src/api/c++/z3++.h                  | 2 +-
 src/smt/smt_conflict_resolution.cpp | 6 +++---
 src/smt/smt_context.cpp             | 1 +
 3 files changed, 5 insertions(+), 4 deletions(-)

diff --git a/src/api/c++/z3++.h b/src/api/c++/z3++.h
index b6157f3ff..104f3ae6c 100644
--- a/src/api/c++/z3++.h
+++ b/src/api/c++/z3++.h
@@ -140,7 +140,7 @@ namespace z3 {
     class context {
         bool       m_enable_exceptions;
         Z3_context m_ctx;
-        static void error_handler(Z3_context /*c*/, Z3_error_code /*e*/) { /* do nothing */ }
+        static void error_handler(Z3_context c, Z3_error_code e) { std::cout << "ex\n"; Z3_THROW(exception(Z3_get_error_msg(c, e))); std::cout << "unreach\n"; }
         void init(config & c) {
             m_ctx = Z3_mk_context_rc(c);
             m_enable_exceptions = true;
diff --git a/src/smt/smt_conflict_resolution.cpp b/src/smt/smt_conflict_resolution.cpp
index 7dd9144fe..8d90f9583 100644
--- a/src/smt/smt_conflict_resolution.cpp
+++ b/src/smt/smt_conflict_resolution.cpp
@@ -59,9 +59,9 @@ namespace smt {
         SASSERT(n->trans_reaches(n->get_root()));
         while (n) {
             if (Set)
-                n->set_mark();
+                n->set_mark2();
             else
-                n->unset_mark();
+                n->unset_mark2();
             n = n->m_trans.m_target;
         }
     }
@@ -84,7 +84,7 @@ namespace smt {
         mark_enodes_in_trans<true>(n1);
         while (true) {
             SASSERT(n2);
-            if (n2->is_marked()) {
+            if (n2->is_marked2()) {
                 mark_enodes_in_trans<false>(n1);
                 return n2;
             }
diff --git a/src/smt/smt_context.cpp b/src/smt/smt_context.cpp
index 9336322f7..6bc5cc6ab 100644
--- a/src/smt/smt_context.cpp
+++ b/src/smt/smt_context.cpp
@@ -4214,6 +4214,7 @@ namespace smt {
         for (unsigned i = 0; i < m_asserted_formulas.get_num_formulas(); ++i) {
             expr* e = m_asserted_formulas.get_formula(i);
             if (is_quantifier(e)) {
+                TRACE("context", tout << mk_pp(e, m) << "\n";);
                 quantifier* q = to_quantifier(e);
                 if (!m.is_rec_fun_def(q)) continue;
                 SASSERT(q->get_num_patterns() == 1);