diff --git a/src/util/lp/eta_matrix.h b/src/util/lp/eta_matrix.h
index eee4a2674..89d2e641d 100644
--- a/src/util/lp/eta_matrix.h
+++ b/src/util/lp/eta_matrix.h
@@ -83,7 +83,7 @@ public:
     void apply_from_right(vector<T> & w) override;
     void apply_from_right(indexed_vector<T> & w) override;
 
-    T get_elem(unsigned i, unsigned j) const;
+    T get_elem(unsigned i, unsigned j) const override;
 #ifdef Z3DEBUG
     unsigned row_count() const override { return m_length; }
     unsigned column_count() const override { return m_length; }
diff --git a/src/util/lp/sparse_matrix.h b/src/util/lp/sparse_matrix.h
index 7649e0983..44111a9fd 100644
--- a/src/util/lp/sparse_matrix.h
+++ b/src/util/lp/sparse_matrix.h
@@ -162,8 +162,8 @@ public:
     unsigned dimension() const {return static_cast<unsigned>(m_row_permutation.size());}
 
 #ifdef Z3DEBUG
-    unsigned row_count() const {return dimension();}
-    unsigned column_count() const {return dimension();}
+    unsigned row_count() const override {return dimension();}
+    unsigned column_count() const override {return dimension();}
 #endif
 
     void init_row_headers();
@@ -302,7 +302,7 @@ public:
     void solve_U_y_indexed_only(indexed_vector<L> & y, const lp_settings&, vector<unsigned> & sorted_active_rows );
 
 #ifdef Z3DEBUG
-    T get_elem(unsigned i, unsigned j) const { return get(i, j); }
+    T get_elem(unsigned i, unsigned j) const override { return get(i, j); }
     unsigned get_number_of_rows() const { return dimension(); }
     unsigned get_number_of_columns() const { return dimension(); }
     void set_number_of_rows(unsigned /*m*/) override { }