fix #4794

src/sat/sat_drat.cpp

@@ -142,11 +142,6 @@ namespace sat {
         buffer[len++] = '\n';
         m_out->write(buffer, len);
 
-        if (n == 3 && c[0] == literal(9357, true) && c[1] == literal(25, true) && c[2] == literal(8691, false)) {
-            m_out->flush();
-            SASSERT(false);
-            UNREACHABLE();
-        }
     }
 
     void drat::dump_activity() {

src/sat/sat_solver.cpp

@@ -3486,7 +3486,6 @@ namespace sat {
             return value(v) != l_undef && lvl(v) <= new_lvl;
         };
 
-
         for (unsigned i = old_num_vars; i < sz; ++i) {
             bool_var v = m_active_vars[i];
             if (is_visited(v) || is_active(v)) {
@@ -3496,7 +3495,9 @@ namespace sat {
             }
             else {
                 set_eliminated(v, true);
-                m_free_vars.push_back(v);
+                if (!is_external(v) || true) {
+                    m_free_vars.push_back(v);
+                }
             }
         }
         m_active_vars.shrink(j);

src/sat/sat_solver.h

@@ -669,6 +669,7 @@ namespace sat {
         void set_should_simplify() { m_next_simplify = m_conflicts_since_init; }
         bool_var_vector const& get_vars_to_reinit() const { return m_vars_to_reinit;  }
         bool is_probing() const { return m_is_probing; }
+        bool is_free(bool_var v) const { return m_free_vars.contains(v); }
 
     public:
         void user_push() override;

src/sat/smt/arith_internalize.cpp

@@ -436,6 +436,7 @@ namespace arith {
         if (_has_var)
             return v;
         theory_var w = mk_evar(n);
+        internalize_term(n);
         svector<lpvar> vars;
         for (unsigned i = 0; i < p; ++i)
             vars.push_back(register_theory_var_in_lar_solver(w));

src/sat/smt/bv_solver.cpp

@@ -360,11 +360,12 @@ namespace bv {
         case bv_justification::kind_t::eq2bit:
             ++s_count;
 //            std::cout << "eq2bit " << s_count << "\n";
-#if 1
+#if 0
             if (s_count == 1899) {
                 std::cout << "eq2bit " << mk_bounded_pp(var2expr(c.m_v1), m) << " == " << mk_bounded_pp(var2expr(c.m_v2), m) << "\n";
-                std::cout << mk_bounded_pp(literal2expr(~c.m_antecedent), m, 2) << "\n";
-                std::cout << mk_bounded_pp(literal2expr(c.m_consequent), m, 2) << "\n";
+                std::cout << mk_bounded_pp(literal2expr(~c.m_antecedent), m, 4) << "\n";
+                std::cout << mk_bounded_pp(literal2expr(c.m_consequent), m, 4) << "\n";
+                std::cout << literal2expr(c.m_consequent) << "\n";
 #if 0
                 solver_ref slv = mk_smt2_solver(m, ctx.s().params());
                 slv->assert_expr(eq);
@@ -779,8 +780,6 @@ namespace bv {
     }
 
     sat::justification solver::mk_eq2bit_justification(theory_var v1, theory_var v2, sat::literal c, sat::literal a) {
-        if (v1 == 3202 && v2 == 3404) std::cout << a << " -> " << c << "\n";
-        SASSERT(!(v1 == 3202 && v2 == 3404 && c.var() == 8691));
         void* mem = get_region().allocate(bv_justification::get_obj_size());
         sat::constraint_base::initialize(mem, this);
         auto* constraint = new (sat::constraint_base::ptr2mem(mem)) bv_justification(v1, v2, c, a);

src/sat/smt/euf_proof.cpp

@@ -76,7 +76,8 @@ namespace euf {
         if (!use_drat())
             return;
         literal_vector lits;
-        for (literal lit : r) lits.push_back(~lit);
+        for (literal lit : r) 
+            lits.push_back(~lit);
         if (l != sat::null_literal)
             lits.push_back(l);
         get_drat().add(lits, sat::status::th(true, get_id()));

src/sat/smt/euf_solver.cpp

@@ -692,6 +692,13 @@ namespace euf {
         finish_reinit();
         for (auto* e : m_solvers)
             e->pop_reinit();
+
+#if 0
+        for (enode* n : m_egraph.nodes()) {
+            if (n->bool_var() != sat::null_bool_var && s().is_free(n->bool_var()))
+                std::cout << "has free " << n->bool_var() << "\n";
+        }
+#endif
     }
 
     bool solver::validate() { 

src/sat/tactic/goal2sat.cpp

@@ -213,7 +213,7 @@ struct goal2sat::imp : public sat::sat_internalizer {
     sat::bool_var to_bool_var(expr* e) override {
         sat::literal l;
         sat::bool_var v = m_map.to_bool_var(e);
-        if (v != sat::null_bool_var)
+        if (v != sat::null_bool_var) 
             return v;
         if (is_app(e) && m_cache.find(to_app(e), l) && !l.sign()) 
             return l.var();

src/shell/drat_frontend.cpp

@@ -71,10 +71,12 @@ class smt_checker {
 
     void add_units() {
         auto const& units = m_drat.units();
+#if 0
         for (unsigned i = m_units.size(); i < units.size(); ++i) {
             sat::literal lit = units[i];            
             m_lemma_solver->assert_expr(lit2expr(lit));
         }
+#endif
         m_units.append(units.size() - m_units.size(), units.c_ptr() + m_units.size());
     }
 
@@ -113,20 +115,22 @@ class smt_checker {
             std::cout << "drup\n";
             return;
         }
-        m_lemma_solver->push();
-        for (auto lit : drup_units)
-            m_lemma_solver->assert_expr(lit2expr(lit));
-        lbool is_sat = m_lemma_solver->check_sat();
+        m_input_solver->push();
+//        for (auto lit : drup_units)
+//            m_input_solver->assert_expr(lit2expr(lit));
+        for (auto lit : lits)
+            m_input_solver->assert_expr(lit2expr(~lit));
+        lbool is_sat = m_input_solver->check_sat();
         if (is_sat != l_false) {
             std::cout << "did not verify: " << lits << "\n";
             for (sat::literal lit : lits) {
                 std::cout << lit2expr(lit) << "\n";
             }
             std::cout << "\n";
-            m_lemma_solver->display(std::cout);
+            m_input_solver->display(std::cout);
             exit(0);
         }
-        m_lemma_solver->pop(1);
+        m_input_solver->pop(1);
         std::cout << "smt\n";
         // check_assertion_redundant(lits);
     }
@@ -280,8 +284,10 @@ static void verify_smt(char const* drat_file, char const* smt_file) {
         switch (r.m_tag) {
         case dimacs::drat_record::tag_t::is_clause:
             checker.add(r.m_lits, r.m_status);
-            if (drat_checker.inconsistent()) 
-                std::cout << "inconsistent\n";            
+            if (drat_checker.inconsistent()) {
+                std::cout << "inconsistent\n";
+                return;
+            }            
             break;
         case dimacs::drat_record::tag_t::is_node: {
             expr_ref e(m);

src/smt/seq_regex.cpp

@@ -278,12 +278,15 @@ namespace smt {
             return;
         }
 
-        update_state_graph(r);
-
-        if (m_state_graph.is_dead(get_state_id(r))) {
-            STRACE("seq_regex_brief", tout << "(dead) ";);
-            th.add_axiom(~lit);
-            return;
+        auto info = re().get_info(r);
+        if (info.interpreted) {
+            update_state_graph(r);
+
+            if (m_state_graph.is_dead(get_state_id(r))) {
+                STRACE("seq_regex_brief", tout << "(dead) ";);
+                th.add_axiom(~lit);
+                return;
+            }
         }
 
         if (block_unfolding(lit, idx)) {