diff --git a/src/api/api_opt.cpp b/src/api/api_opt.cpp
index 8c2faec11..e20c78738 100644
--- a/src/api/api_opt.cpp
+++ b/src/api/api_opt.cpp
@@ -199,7 +199,7 @@ extern "C" {
 
     Z3_string Z3_API Z3_optimize_get_reason_unknown(Z3_context c, Z3_optimize o) {
         Z3_TRY;
-        LOG_Z3_optimize_to_string(c, o);
+        LOG_Z3_optimize_get_reason_unknown(c, o);
         RESET_ERROR_CODE();
         return mk_c(c)->mk_external_string(to_optimize_ptr(o)->reason_unknown());
         Z3_CATCH_RETURN("");
diff --git a/src/ast/display_dimacs.cpp b/src/ast/display_dimacs.cpp
index bb9ed94bb..50a1ff6d0 100644
--- a/src/ast/display_dimacs.cpp
+++ b/src/ast/display_dimacs.cpp
@@ -123,3 +123,8 @@ std::ostream& display_dimacs(std::ostream& out, expr_ref_vector const& fmls, boo
     }
     return out;
 }
+
+std::ostream& display_wcnf(std::ostream& out, expr_ref_vector const& fmls, vector<std::pair<expr*,unsigned>> const& soft, bool include_names) {
+    NOT_IMPLEMENTED_YET();
+    return out;
+}
diff --git a/src/ast/display_dimacs.h b/src/ast/display_dimacs.h
index 2c70be936..a50684682 100644
--- a/src/ast/display_dimacs.h
+++ b/src/ast/display_dimacs.h
@@ -22,3 +22,5 @@ Revision History:
 
 std::ostream& display_dimacs(std::ostream& out, expr_ref_vector const& fmls, bool include_names);
 
+std::ostream& display_wcnf(std::ostream& out, expr_ref_vector const& fmls, vector<std::pair<expr*,unsigned>> const& soft, bool include_names);
+
diff --git a/src/opt/opt_context.cpp b/src/opt/opt_context.cpp
index 0789cb2a4..2307c2488 100644
--- a/src/opt/opt_context.cpp
+++ b/src/opt/opt_context.cpp
@@ -1550,6 +1550,27 @@ namespace opt {
         return to_string(true, m_hard_constraints, m_objectives);
     }
 
+    std::string context::to_wcnf() {
+        import_scoped_state(); 
+        expr_ref_vector asms(m);
+        normalize(asms);
+        auto const& objectives = m_objectives;
+        if (objectives.size() > 1)
+            throw default_exception("only single objective weighted MaxSAT wcnf output is supported");
+        if (objectives.size() == 1) {
+            auto const& obj = objectives[0];
+            if (obj.m_type != O_MAXSMT)
+                throw default_exception("only single objective weighted MaxSAT wcnf output is supported");
+            for (unsigned j = 0; j < obj.m_terms.size(); ++j) {
+                rational w = obj.m_weights[j];
+                if (!w.is_unsigned())
+                    throw default_exception("only single objective weighted MaxSAT wcnf output is supported");
+            }
+        }
+        NOT_IMPLEMENTED_YET();
+        return std::string("");
+    }
+
     std::string context::to_string(bool is_internal, expr_ref_vector const& hard, vector<objective> const& objectives) const {
         smt2_pp_environment_dbg env(m);
         ast_pp_util visitor(m);
diff --git a/src/opt/opt_context.h b/src/opt/opt_context.h
index 7bf7ce7e2..8a6df7129 100644
--- a/src/opt/opt_context.h
+++ b/src/opt/opt_context.h
@@ -322,7 +322,7 @@ namespace opt {
 
         std::string to_string(bool is_internal, expr_ref_vector const& hard, vector<objective> const& objectives) const;
         std::string to_string_internal() const;
-
+        std::string to_wcnf();
 
         void validate_lex();
         void validate_maxsat(symbol const& id);