diff --git a/src/opt/maxsmt.cpp b/src/opt/maxsmt.cpp
index b2f09f3c1..2edb28504 100644
--- a/src/opt/maxsmt.cpp
+++ b/src/opt/maxsmt.cpp
@@ -59,6 +59,16 @@ namespace opt {
                        verbose_stream() << "Satisfying soft constraints\n";
                        display_answer(verbose_stream());
                    });
+
+        DEBUG_CODE(if (is_sat == l_true) {
+                IF_VERBOSE(0, verbose_stream() << "validating assignment\n";);
+                m_s->push();
+                commit_assignment();
+                VERIFY(is_sat == m_s->check_sat(0,0));
+                m_s->pop(1);
+                // TBD: check that all extensions are unsat too
+
+            });
         return is_sat;
     }
 
diff --git a/src/opt/opt_context.cpp b/src/opt/opt_context.cpp
index 7e62605ac..6afc7779e 100644
--- a/src/opt/opt_context.cpp
+++ b/src/opt/opt_context.cpp
@@ -70,8 +70,8 @@ namespace opt {
         lbool is_sat = l_true;
         map_t::iterator it = m_maxsmts.begin(), end = m_maxsmts.end();
         for (; is_sat == l_true && it != end; ++it) {
-            maxsmt* ms = it->m_value;
-            is_sat = (*ms)(s);
+            maxsmt& ms = *it->m_value;
+            is_sat = ms(s);
         }
         if (is_sat == l_true) {           
             is_sat = m_optsmt(s);
@@ -160,5 +160,4 @@ namespace opt {
         }
     }
 
-
 }
diff --git a/src/opt/opt_context.h b/src/opt/opt_context.h
index c54259115..081bf7c1d 100644
--- a/src/opt/opt_context.h
+++ b/src/opt/opt_context.h
@@ -60,6 +60,8 @@ namespace opt {
     private:
         lbool optimize_pareto();
         lbool optimize_box();
+
+        void validate_feasibility(maxsmt& ms);
     };
 
 }
diff --git a/src/smt/theory_pb.cpp b/src/smt/theory_pb.cpp
index 68d627748..2b42e39f9 100644
--- a/src/smt/theory_pb.cpp
+++ b/src/smt/theory_pb.cpp
@@ -921,7 +921,6 @@ namespace smt {
               display(tout, c););
 
         DEBUG_CODE(
-            IF_VERBOSE(0, verbose_stream() << s_debug_conflict << "\n";);
             if (s_debug_conflict) {
                 resolve_conflict(conseq, c);
             });