diff --git a/src/opt/maxres.cpp b/src/opt/maxres.cpp
index 912a64038..f52c56a60 100644
--- a/src/opt/maxres.cpp
+++ b/src/opt/maxres.cpp
@@ -321,10 +321,10 @@ public:
     void found_optimum() {
         IF_VERBOSE(1, verbose_stream() << "found optimum\n";);
         m_lower.reset();
-        for (unsigned i = 0; i < m_soft.size(); ++i) {
-            m_assignment[i] = m_model->is_true(m_soft[i]);
-            if (!m_assignment[i]) {
-                m_lower += m_weights[i];
+        for (soft& s : m_soft) {
+            s.is_true = m_model->is_true(s.s);
+            if (!s.is_true) {
+                m_lower += s.weight;
             }
         }
         m_upper = m_lower;
@@ -375,24 +375,22 @@ public:
             }
             // 1. remove all core literals from m_asms
             // 2. re-add literals of higher weight than min-weight.
-            // 3. 'core' stores the core literals that are split afterwards
+            // 3. 'core' stores the core literals that are
+            //    re-encoded as assumptions, afterwards
             remove_soft(core, m_asms);
             split_core(core);
             cores.push_back(core);
-            if (core.size() >= m_max_core_size) {
-                break;
-            }
-            if (cores.size() >= m_max_num_cores) {
-                break;
-            }
+
+            if (core.size()  >= m_max_core_size) break;
+            if (cores.size() >= m_max_num_cores) break;
+
             is_sat = check_sat_hill_climb(m_asms);            
         }
+
         TRACE("opt", 
-              tout << "num cores: " << cores.size() << "\n";
-              for (auto const& c : cores) {
-                  display_vec(tout, c);
-              }
-              tout << "num satisfying: " << m_asms.size() << "\n";);
+              tout << "sat: " << is_sat << " num cores: " << cores.size() << "\n";
+              for (auto const& c : cores) display_vec(tout, c);
+              tout << "num assumptions: " << m_asms.size() << "\n";);
         
         return is_sat;
     }
@@ -411,7 +409,6 @@ public:
             if (mdl->is_false(a)) {
                 cs.push_back(a);
             }
-            // TRACE("opt", tout << mk_pp(a, m) << ": " << (*mdl)(a) << "\n";);
         }
         TRACE("opt", display_vec(tout << "new correction set: ", cs););
     }
@@ -475,8 +472,8 @@ public:
 
     unsigned max_core_size(vector<exprs> const& cores) {
         unsigned result = 0;
-        for (unsigned i = 0; i < cores.size(); ++i) {
-            result = std::max(cores[i].size(), result);
+        for (auto const& c : cores) {
+            result = std::max(c.size(), result);
         }
         return result;
     }
@@ -725,13 +722,11 @@ public:
 
         rational upper(0);
 
-        unsigned i = 0;
-        for (expr* s : m_soft) {
-            TRACE("opt", tout << mk_pp(s, m) << ": " << (*mdl)(s) << " " << m_weights[i] << "\n";);
-            if (!mdl->is_true(s)) {
-                upper += m_weights[i];
+        for (soft& s : m_soft) {
+            TRACE("opt", tout << s.s << ": " << (*mdl)(s.s) << " " << s.weight << "\n";);
+            if (!mdl->is_true(s.s)) {
+                upper += s.weight;
             }
-            ++i;
         }
 
         if (upper > m_upper) {
@@ -748,9 +743,8 @@ public:
 
         TRACE("opt", tout << "updated upper: " << upper << "\nmodel\n" << *m_model;);
 
-        i = 0;
-        for (expr* s : m_soft) {
-            m_assignment[i++] = m_model->is_true(s);
+        for (soft& s : m_soft) {
+            s.is_true = m_model->is_true(s.s);
         }
        
         // DEBUG_CODE(verify_assignment(););
@@ -766,11 +760,13 @@ public:
         if (!m_add_upper_bound_block) return;
         pb_util u(m);
         expr_ref_vector nsoft(m);
+        vector<rational> weights;
         expr_ref fml(m);
-        for (expr* s : m_soft) {
-            nsoft.push_back(mk_not(m, s));
+        for (soft& s : m_soft) {
+            nsoft.push_back(mk_not(m, s.s));
+            weights.push_back(s.weight);
         }            
-        fml = u.mk_lt(nsoft.size(), m_weights.c_ptr(), nsoft.c_ptr(), m_upper);
+        fml = u.mk_lt(nsoft.size(), weights.c_ptr(), nsoft.c_ptr(), m_upper);
         TRACE("opt", tout << "block upper bound " << fml << "\n";);;
         s().assert_expr(fml); 
     }
@@ -832,9 +828,7 @@ public:
     void verify_core(exprs const& core) {
         IF_VERBOSE(3, verbose_stream() << "verify core\n";);                
         ref<solver> smt_solver = mk_smt_solver(m, m_params, symbol());
-        for (unsigned i = 0; i < s().get_num_assertions(); ++i) {
-            smt_solver->assert_expr(s().get_assertion(i));
-        }
+        smt_solver->assert_expr(s().get_assertions());
         smt_solver->assert_expr(core);
         lbool is_sat = smt_solver->check_sat(0, nullptr);
         if (is_sat == l_true) {
@@ -845,13 +839,11 @@ public:
     void verify_assignment() {
         IF_VERBOSE(1, verbose_stream() << "verify assignment\n";);        
         ref<solver> smt_solver = mk_smt_solver(m, m_params, symbol());
-        for (unsigned i = 0; i < s().get_num_assertions(); ++i) {
-            smt_solver->assert_expr(s().get_assertion(i));
-        }
+        smt_solver->assert_expr(s().get_assertions());
         expr_ref n(m);
-        for (unsigned i = 0; i < m_soft.size(); ++i) {
-            n = m_soft[i];
-            if (!m_assignment[i]) {
+        for (soft& s : m_soft) {
+            n = s.s;
+            if (!s.is_true) {
                 n = mk_not(m, n);
             }
             smt_solver->assert_expr(n);
diff --git a/src/opt/maxsmt.cpp b/src/opt/maxsmt.cpp
index c97b818cf..1b44b578b 100644
--- a/src/opt/maxsmt.cpp
+++ b/src/opt/maxsmt.cpp
@@ -34,16 +34,17 @@ Notes:
 namespace opt {
 
     maxsmt_solver_base::maxsmt_solver_base(
-        maxsat_context& c, vector<rational> const& ws, expr_ref_vector const& soft):
+        maxsat_context& c, vector<rational> const& ws, expr_ref_vector const& softs):
         m(c.get_manager()), 
         m_c(c),
-        m_soft(soft),
-        m_weights(ws),
         m_assertions(m),
         m_trail(m) {
         c.get_base_model(m_model);
         SASSERT(m_model);
         updt_params(c.params());
+        for (unsigned i = 0; i < ws.size(); ++i) {
+            m_soft.push_back(soft(expr_ref(softs.get(i), m), ws[i], false));
+        }
     }
     
     void maxsmt_solver_base::updt_params(params_ref& p) {
@@ -56,17 +57,21 @@ namespace opt {
 
     void maxsmt_solver_base::commit_assignment() {
         expr_ref tmp(m);
+        expr_ref_vector fmls(m);
         rational k(0), cost(0);
-        for (unsigned i = 0; i < m_soft.size(); ++i) {
-            if (get_assignment(i)) {
-                k += m_weights[i];
+        vector<rational> weights;
+        for (soft const& s : m_soft) {
+            if (s.is_true) {
+                k += s.weight;
             }
             else {
-                cost += m_weights[i];
+                cost += s.weight;
             }
+            weights.push_back(s.weight);
+            fmls.push_back(s.s);
         }       
         pb_util pb(m);
-        tmp = pb.mk_ge(m_weights.size(), m_weights.c_ptr(), m_soft.c_ptr(), k);
+        tmp = pb.mk_ge(weights.size(), weights.c_ptr(), fmls.c_ptr(), k);
         TRACE("opt", tout << "cost: " << cost << "\n" << tmp << "\n";);
         s().assert_expr(tmp);
     }
@@ -74,19 +79,14 @@ namespace opt {
     bool maxsmt_solver_base::init() {
         m_lower.reset();
         m_upper.reset();
-        m_assignment.reset();
-        for (unsigned i = 0; i < m_weights.size(); ++i) {
-            m_assignment.push_back(m.is_true(m_soft[i]));
-            if (!m_assignment.back()) {
-                m_upper += m_weights[i];
-            }
+        for (soft& s : m_soft) {
+            s.is_true = m.is_true(s.s);
+            if (!s.is_true) m_upper += s.weight;
         }
         
         TRACE("opt", 
               tout << "upper: " << m_upper << " assignments: ";
-              for (unsigned i = 0; i < m_weights.size(); ++i) {
-                  tout << (m_assignment[i]?"T":"F");
-              }
+              for (soft& s : m_soft) tout << (s.is_true?"T":"F");              
               tout << "\n";);
         return true;
     }
@@ -141,6 +141,7 @@ namespace opt {
     maxsmt_solver_base::scoped_ensure_theory::scoped_ensure_theory(maxsmt_solver_base& s) {
         m_wth = s.ensure_wmax_theory();
     }
+
     maxsmt_solver_base::scoped_ensure_theory::~scoped_ensure_theory() {
         if (m_wth) {
             m_wth->reset_local();
@@ -159,11 +160,13 @@ namespace opt {
 
     lbool maxsmt_solver_base::find_mutexes(obj_map<expr, rational>& new_soft) {
         m_lower.reset();
-        for (unsigned i = 0; i < m_soft.size(); ++i) {
-            new_soft.insert(m_soft[i], m_weights[i]);
+        expr_ref_vector fmls(m);
+        for (soft& s : m_soft) {
+            new_soft.insert(s.s, s.weight);
+            fmls.push_back(s.s);
         }
         vector<expr_ref_vector> mutexes;
-        lbool is_sat = s().find_mutexes(m_soft, mutexes);
+        lbool is_sat = s().find_mutexes(fmls, mutexes);
         if (is_sat != l_true) {
             return is_sat;
         }
diff --git a/src/opt/maxsmt.h b/src/opt/maxsmt.h
index 422cf26b9..de38baf32 100644
--- a/src/opt/maxsmt.h
+++ b/src/opt/maxsmt.h
@@ -56,17 +56,26 @@ namespace opt {
     // 
     class maxsmt_solver_base : public maxsmt_solver {
     protected:
+        struct soft { 
+            expr_ref  s; 
+            rational  weight; 
+            bool      is_true;
+            soft(expr_ref& s, rational const& w, bool t): s(s), weight(w), is_true(t) {}
+            soft(soft const& other):s(other.s), weight(other.weight), is_true(other.is_true) {}
+            soft& operator=(soft const& other) { s = other.s; weight = other.weight; is_true = other.is_true; return *this; }            
+        };
         ast_manager&     m;
-        maxsat_context&  m_c;
-        const expr_ref_vector  m_soft;
-        vector<rational> m_weights;
+        maxsat_context&  m_c;        
+        vector<soft>     m_soft;
         expr_ref_vector  m_assertions;
         expr_ref_vector  m_trail;
         rational         m_lower;
         rational         m_upper;
         model_ref        m_model;
         svector<symbol>  m_labels;
-        svector<bool>    m_assignment;       // truth assignment to soft constraints
+        //const expr_ref_vector  m_soft;
+        //vector<rational> m_weights;
+        //svector<bool>    m_assignment;       // truth assignment to soft constraints
         params_ref       m_params;           // config
 
     public:
@@ -75,7 +84,7 @@ namespace opt {
         ~maxsmt_solver_base() override {}
         rational get_lower() const override { return m_lower; }
         rational get_upper() const override { return m_upper; }
-        bool get_assignment(unsigned index) const override { return m_assignment[index]; }
+        bool get_assignment(unsigned index) const override { return m_soft[index].is_true; }
         void collect_statistics(statistics& st) const override { }
         void get_model(model_ref& mdl, svector<symbol>& labels) override { mdl = m_model.get(); labels = m_labels;}
         virtual void commit_assignment();
diff --git a/src/opt/sortmax.cpp b/src/opt/sortmax.cpp
index 6e7e6ec78..4313cfbec 100644
--- a/src/opt/sortmax.cpp
+++ b/src/opt/sortmax.cpp
@@ -114,9 +114,7 @@ namespace opt {
         }
 
         void update_assignment() {
-            for (unsigned i = 0; i < m_soft.size(); ++i) {
-                m_assignment[i] = is_true(m_soft[i]);
-            }
+            for (soft& s : m_soft) s.is_true = is_true(s.s);
         }
 
         bool is_true(expr* e) {
diff --git a/src/opt/wmax.cpp b/src/opt/wmax.cpp
index 97231f69e..e4eb7e06b 100644
--- a/src/opt/wmax.cpp
+++ b/src/opt/wmax.cpp
@@ -124,10 +124,7 @@ namespace opt {
         }
 
         void update_assignment() {
-            m_assignment.reset();
-            for (unsigned i = 0; i < m_soft.size(); ++i) {
-                m_assignment.push_back(is_true(m_soft[i]));
-            }
+            for (soft& s : m_soft) s.is_true = is_true(s.s);
         }
 
         struct compare_asm {
diff --git a/src/solver/solver.cpp b/src/solver/solver.cpp
index 186449545..4044c4a85 100644
--- a/src/solver/solver.cpp
+++ b/src/solver/solver.cpp
@@ -64,6 +64,13 @@ void solver::get_assertions(expr_ref_vector& fmls) const {
     }
 }
 
+expr_ref_vector solver::get_assertions() const {
+    expr_ref_vector result(get_manager());
+    get_assertions(result);
+    return result;
+}
+
+
 struct scoped_assumption_push {
     expr_ref_vector& m_vec;
     scoped_assumption_push(expr_ref_vector& v, expr* e): m_vec(v) { v.push_back(e); }
diff --git a/src/solver/solver.h b/src/solver/solver.h
index c4df362e4..c371be284 100644
--- a/src/solver/solver.h
+++ b/src/solver/solver.h
@@ -179,6 +179,8 @@ public:
     */
     void get_assertions(expr_ref_vector& fmls) const;
 
+    expr_ref_vector get_assertions() const;
+
     /**
     \brief The number of tracked assumptions (see assert_expr(t, a)).
     */
diff --git a/src/test/qe_arith.cpp b/src/test/qe_arith.cpp
index d18e0f717..031912c46 100644
--- a/src/test/qe_arith.cpp
+++ b/src/test/qe_arith.cpp
@@ -88,8 +88,7 @@ static void test(app* var, expr_ref& fml) {
     std::cout << "projected: " << mk_pp(pr,  m) << "\n";
 
     // projection is consistent with model.
-    expr_ref tmp(m);
-    VERIFY(md->eval(pr, tmp) && m.is_true(tmp));       
+    VERIFY(md->is_true(pr));
 
     // projection implies E x. fml
     {