Use = default for virtual constructors.

src/ast/ast.h

@@ -1024,7 +1024,7 @@ protected:
     friend class ast_manager;
 
 public:
-    virtual ~decl_plugin() {}
+    virtual ~decl_plugin() = default;
     virtual void finalize() {}
 
 
@@ -2582,7 +2582,7 @@ class ast_mark {
     obj_mark<expr>                        m_expr_marks;
     obj_mark<decl, bit_vector, decl2uint> m_decl_marks;
 public:
-    virtual ~ast_mark() {}
+    virtual ~ast_mark() = default;
     bool is_marked(ast * n) const;
     virtual void mark(ast * n, bool flag);
     virtual void reset();

src/ast/ast_printer.h

@@ -24,7 +24,7 @@ Revision History:
 
 class ast_printer {
 public:
-    virtual ~ast_printer() {}
+    virtual ~ast_printer() = default;
     virtual void pp(sort * s, format_ns::format_ref & r) const { UNREACHABLE(); }
     virtual void pp(func_decl * f, format_ns::format_ref & r) const { UNREACHABLE(); }
     virtual void pp(expr * n, unsigned num_vars, char const * var_prefix, format_ns::format_ref & r, sbuffer<symbol> & var_names) const { UNREACHABLE(); }

src/ast/ast_smt2_pp.h

@@ -46,7 +46,7 @@ protected:
     format_ns::format * pp_as(format_ns::format * fname, sort * s);
     format_ns::format * pp_signature(format_ns::format * f_name, func_decl * f);
 public:
-    virtual ~smt2_pp_environment() {}
+    virtual ~smt2_pp_environment() = default;
     virtual ast_manager & get_manager() const = 0;
     virtual arith_util & get_autil() = 0;
     virtual bv_util & get_bvutil() = 0;

src/ast/datatype_decl_plugin.h

@@ -105,7 +105,7 @@ namespace datatype {
         class size {
             unsigned m_ref{ 0 };
         public:
-            virtual ~size() { }
+            virtual ~size() = default;
             void inc_ref() { ++m_ref; }
             void dec_ref();
             static size* mk_offset(sort_size const& s); 

src/ast/expr_functors.h

@@ -27,14 +27,14 @@ Revision History:
 class i_expr_pred {
 public:
     virtual bool operator()(expr* e) = 0;
-    virtual ~i_expr_pred() {}
+    virtual ~i_expr_pred() = default;
 };
 
 
 class i_sort_pred {
 public:
     virtual bool operator()(sort* s) = 0;
-    virtual ~i_sort_pred() {}
+    virtual ~i_sort_pred() = default;
 };
 
 

src/ast/macros/quantifier_macro_info.h

@@ -39,7 +39,7 @@ protected:
     void collect_macro_candidates(quantifier* q);
 public:
     quantifier_macro_info(ast_manager& m, quantifier* q);
-    virtual ~quantifier_macro_info() {}
+    virtual ~quantifier_macro_info() = default;
     bool is_auf() const { return m_is_auf; }
     quantifier* get_flat_q() const { return m_flat_q; }
     bool has_cond_macros() const { return !m_cond_macros.empty(); }

src/ast/normal_forms/elim_term_ite.h

@@ -31,7 +31,7 @@ public:
     elim_term_ite_cfg(ast_manager & m, defined_names & d): m(m), m_defined_names(d) { 
         // TBD enable_ac_support(false);
     }
-    virtual ~elim_term_ite_cfg() {}
+    virtual ~elim_term_ite_cfg() = default;
     vector<justified_expr> const& new_defs() const { return m_new_defs; }
     br_status reduce_app(func_decl* f, unsigned n, expr *const* args, expr_ref& result, proof_ref& result_pr);
     void push() { m_lim.push_back(m_new_defs.size()); }

src/ast/normal_forms/name_exprs.h

@@ -29,7 +29,7 @@ public:
 
 class name_exprs {
 public:
-    virtual ~name_exprs() {}
+    virtual ~name_exprs() = default;
     virtual void operator()(expr * n,                          // [IN] expression that contain the sub-expressions to be named
                             expr_ref_vector & new_defs,        // [OUT] new definitions
                             proof_ref_vector & new_def_proofs, // [OUT] proofs of the new definitions 

src/ast/recfun_decl_plugin.h

@@ -49,7 +49,7 @@ namespace recfun {
 
     class replace {
     public:
-        virtual ~replace() {}
+        virtual ~replace() = default;
         virtual void reset() = 0;
         virtual void insert(expr* d, expr* r) = 0;
         virtual expr_ref operator()(expr* e) = 0;

src/ast/rewriter/expr_replacer.h

@@ -28,7 +28,7 @@ Notes:
 class expr_replacer {
     struct scoped_set_subst;
 public:
-    virtual ~expr_replacer() {}
+    virtual ~expr_replacer() = default;
 
     virtual ast_manager & m() const = 0;
     virtual void set_substitution(expr_substitution * s) = 0;

src/ast/rewriter/seq_rewriter.h

@@ -83,7 +83,7 @@ public:
 
 class expr_solver {
 public:
-    virtual ~expr_solver() {}
+    virtual ~expr_solver() = default;
     virtual lbool check_sat(expr* e) = 0;
 };
 

src/ast/substitution/substitution_tree.h

@@ -29,7 +29,7 @@ protected:
     substitution & m_subst;
 public:
     st_visitor(substitution & s):m_subst(s) {}
-    virtual ~st_visitor() {}
+    virtual ~st_visitor() = default;
     substitution & get_substitution() { return m_subst; }
     virtual bool operator()(expr * e) { return true; }
 };

src/ast/value_generator.h

@@ -23,7 +23,7 @@
 
 class value_generator_core {
  public:        
-    virtual ~value_generator_core() {}
+    virtual ~value_generator_core() = default;
     virtual family_id get_fid() const = 0;
     virtual expr_ref get_value(sort* s, unsigned index) = 0;
 };