[01/11] Use smart pointers for variables exported from the ABI corpus

diff --git a/include/abg-comparison.h b/include/abg-comparison.h
index 3178c97a..b0527e79 100644
--- a/include/abg-comparison.h
+++ b/include/abg-comparison.h
@@ -225,7 +225,7 @@  typedef unordered_map<string, method_decl_sptr> string_member_function_sptr_map;
 
 /// Convenience typedef for a map which key is a string and which
 /// value is a point to @ref var_decl.
-typedef unordered_map<string, const var_decl*> string_var_ptr_map;
+typedef unordered_map<string, var_decl_sptr> string_var_ptr_map;
 
 /// Convenience typedef for a pair of pointer to @ref var_decl
 /// representing a @ref var_decl change.  The first member of the pair
diff --git a/include/abg-corpus.h b/include/abg-corpus.h
index cbadbdb2..2cebad2e 100644
--- a/include/abg-corpus.h
+++ b/include/abg-corpus.h
@@ -34,10 +34,10 @@  public:
   typedef std::unordered_set<const function_decl*> functions_set;
 
   ///Convenience typedef for std::vector<abigail::ir::var_decl*>
-  typedef vector<const var_decl*> variables;
+  typedef vector<var_decl_sptr> variables;
 
   /// Convenience typedef for std::unordered_set<const var_decl*>.
-  typedef std::unordered_set<const var_decl*> variables_set;
+  typedef std::unordered_set<var_decl_sptr> variables_set;
 
   class exported_decls_builder;
 
@@ -230,7 +230,7 @@  public:
   const std::unordered_set<function_decl*>*
   lookup_functions(const char* id) const;
 
-  const var_decl*
+  const var_decl_sptr
   lookup_variable(const interned_string& id) const;
 
   void
@@ -370,7 +370,7 @@  public:
   maybe_add_fn_to_exported_fns(function_decl*);
 
   bool
-  maybe_add_var_to_exported_vars(const var_decl*);
+  maybe_add_var_to_exported_vars(const var_decl_sptr&);
 }; //corpus::exported_decls_builder
 
 /// Abstraction of a group of corpora.
diff --git a/include/abg-fe-iface.h b/include/abg-fe-iface.h
index 119ab7ce..65bc0493 100644
--- a/include/abg-fe-iface.h
+++ b/include/abg-fe-iface.h
@@ -145,7 +145,7 @@  protected:
   add_fn_to_exported_or_undefined_decls(const function_decl* fn);
 
   void
-  add_var_to_exported_or_undefined_decls(const var_decl* var);
+  add_var_to_exported_or_undefined_decls(const var_decl_sptr& var);
 
   virtual ir::corpus_sptr
   read_corpus(status& status) = 0;
diff --git a/include/abg-ir.h b/include/abg-ir.h
index 348cce3c..1e89d06c 100644
--- a/include/abg-ir.h
+++ b/include/abg-ir.h
@@ -579,7 +579,7 @@  typedef unordered_map<interned_string,
 		      hash_interned_string> istring_function_decl_ptr_map_type;
 
 typedef unordered_map<interned_string,
-		      const var_decl*,
+		      var_decl_sptr,
 		      hash_interned_string> istring_var_decl_ptr_map_type;
 
 /// This is a type that aggregates maps of all the kinds of types that
diff --git a/src/abg-btf-reader.cc b/src/abg-btf-reader.cc
index ec13d267..ad610410 100644
--- a/src/abg-btf-reader.cc
+++ b/src/abg-btf-reader.cc
@@ -661,7 +661,7 @@  public:
     if (function_decl_sptr fn = is_function_decl(result))
       add_fn_to_exported_or_undefined_decls(fn.get());
     else if (var_decl_sptr var = is_var_decl(result))
-      add_var_to_exported_or_undefined_decls(var.get());
+      add_var_to_exported_or_undefined_decls(var);
 
     return result;
   }
diff --git a/src/abg-comparison-priv.h b/src/abg-comparison-priv.h
index db7946ae..1cd92790 100644
--- a/src/abg-comparison-priv.h
+++ b/src/abg-comparison-priv.h
@@ -1013,6 +1013,10 @@  struct var_comp
   bool
   operator() (const var_decl* l, const var_decl* r) const
   {return operator()(*l, *r);}
+
+  bool
+  operator() (const var_decl_sptr& l, const var_decl_sptr& r) const
+  {return operator()(l.get(), r.get());}
 };// end struct var_comp
 
 /// A functor to compare instances of @ref elf_symbol base on their
@@ -1147,10 +1151,10 @@  struct corpus_diff::priv
   added_function_is_suppressed(const function_decl* fn) const;
 
   bool
-  deleted_variable_is_suppressed(const var_decl* var) const;
+  deleted_variable_is_suppressed(const var_decl_sptr& var) const;
 
   bool
-  added_variable_is_suppressed(const var_decl* var) const;
+  added_variable_is_suppressed(const var_decl_sptr& var) const;
 
   bool
   added_unreachable_type_is_suppressed(const type_base *t)const ;
@@ -1434,7 +1438,7 @@  sort_string_elf_symbol_map(const string_elf_symbol_map& map,
 
 void
 sort_string_var_ptr_map(const string_var_ptr_map& map,
-			vector<const var_decl*>& sorted);
+			vector<var_decl_sptr>& sorted);
 
 void
 sort_string_data_member_diff_sptr_map(const string_var_diff_sptr_map& map,
diff --git a/src/abg-comparison.cc b/src/abg-comparison.cc
index 65996a84..87a2e4a9 100644
--- a/src/abg-comparison.cc
+++ b/src/abg-comparison.cc
@@ -324,7 +324,7 @@  sort_string_elf_symbol_map(const string_elf_symbol_map& map,
 /// @param sorted out parameter; the sorted vector of @ref var_decl.
 void
 sort_string_var_ptr_map(const string_var_ptr_map& map,
-			vector<const var_decl*>& sorted)
+			vector<var_decl_sptr>& sorted)
 {
   for (string_var_ptr_map::const_iterator i = map.begin();
        i != map.end();
@@ -9685,7 +9685,7 @@  corpus_diff::priv::ensure_lookup_tables_populated()
 	unsigned i = it->index();
 	ABG_ASSERT(i < first_->get_variables().size());
 
-	const var_decl* deleted_var = first_->get_variables()[i];
+	const var_decl_sptr deleted_var = first_->get_variables()[i];
 	string n = deleted_var->get_id();
 	ABG_ASSERT(!n.empty());
 	ABG_ASSERT(deleted_vars_.find(n) == deleted_vars_.end());
@@ -9702,7 +9702,7 @@  corpus_diff::priv::ensure_lookup_tables_populated()
 	     ++iit)
 	  {
 	    unsigned i = *iit;
-	    const var_decl* added_var = second_->get_variables()[i];
+	    const var_decl_sptr added_var = second_->get_variables()[i];
 	    string n = added_var->get_id();
 	    ABG_ASSERT(!n.empty());
 	    {
@@ -9720,10 +9720,8 @@  corpus_diff::priv::ensure_lookup_tables_populated()
 	      {
 		if (*j->second != *added_var)
 		  {
-		    var_decl_sptr f(const_cast<var_decl*>(j->second),
-				    noop_deleter());
-		    var_decl_sptr s(const_cast<var_decl*>(added_var),
-				    noop_deleter());
+		    var_decl_sptr f = j->second;
+		    var_decl_sptr s = added_var;
 		    changed_vars_map_[n] = compute_diff(f, s, ctxt);
 		  }
 		deleted_vars_.erase(j);
@@ -10173,7 +10171,7 @@  function_is_suppressed(const function_decl* fn,
 /// change reports about variable @p fn, if that variable changes in
 /// the way expressed by @p k.
 static bool
-variable_is_suppressed(const var_decl* var,
+variable_is_suppressed(const var_decl_sptr& var,
 		       const suppression_sptr suppr,
 		       variable_suppression::change_kind k,
 		       const diff_context_sptr ctxt)
@@ -10425,7 +10423,7 @@  corpus_diff::priv::added_function_is_suppressed(const function_decl* fn) const
 /// @return true iff the change reports for a give given deleted
 /// variable has been deleted.
 bool
-corpus_diff::priv::deleted_variable_is_suppressed(const var_decl* var) const
+corpus_diff::priv::deleted_variable_is_suppressed(const var_decl_sptr& var) const
 {
   if (!var)
     return false;
@@ -10444,7 +10442,7 @@  corpus_diff::priv::deleted_variable_is_suppressed(const var_decl* var) const
 /// @return true iff the change reports for a given deleted
 /// variable has been deleted.
 bool
-corpus_diff::priv::added_variable_is_suppressed(const var_decl* var) const
+corpus_diff::priv::added_variable_is_suppressed(const var_decl_sptr& var) const
 {
   if (!var)
     return false;
diff --git a/src/abg-corpus-priv.h b/src/abg-corpus-priv.h
index 485c77dc..100eaee7 100644
--- a/src/abg-corpus-priv.h
+++ b/src/abg-corpus-priv.h
@@ -55,12 +55,12 @@  typedef unordered_map<interned_string,
 
 /// Convenience typedef for a hash map which key is a string and
 /// which data is an abigail::ir::var_decl*.
-typedef unordered_map<string, var_decl*> str_var_ptr_map_type;
+typedef unordered_map<string, var_decl_sptr> str_var_ptr_map_type;
 
 /// Convenience typedef for a hash map which key is an interned_string
 /// and which data is an abigail::ir::var_decl*.
 typedef unordered_map<interned_string,
-		      var_decl*,
+		      var_decl_sptr,
 		      hash_interned_string> istr_var_ptr_map_type;
 
 /// The type of the private data of @ref
@@ -449,7 +449,7 @@  public:
   ///
   /// @param id the variable to add to the map.
   void
-  add_var_to_map(var_decl* var)
+  add_var_to_map(const var_decl_sptr& var)
   {
     if (var)
       {
@@ -475,13 +475,13 @@  public:
   ///
   /// @param fn the variable to add to the set of exported variables.
   void
-  add_var_to_exported(const var_decl* var)
+  add_var_to_exported(const var_decl_sptr& var)
   {
     const interned_string& id = get_id(*var);
     if (!var_id_is_in_id_var_map(id))
       {
-	vars_.push_back(const_cast<var_decl*>(var));
-	add_var_to_map(const_cast<var_decl*>(var));
+	vars_.push_back(var);
+	add_var_to_map(var);
       }
   }
 
@@ -617,7 +617,7 @@  public:
   ///
   /// @return true iff the variable is to be kept.
   bool
-  keep_wrt_id_of_vars_to_keep(const var_decl* var)
+  keep_wrt_id_of_vars_to_keep(const var_decl_sptr& var)
   {
     if (!var)
       return false;
@@ -662,7 +662,7 @@  public:
   ///
   /// @return true iff the variable is to be kept.
   bool
-  keep_wrt_regex_of_vars_to_suppress(const var_decl *var)
+  keep_wrt_regex_of_vars_to_suppress(const var_decl_sptr var)
   {
     if (!var)
       return false;
@@ -691,7 +691,7 @@  public:
   ///
   /// @return true iff the variable is to be kept.
   bool
-  keep_wrt_regex_of_vars_to_keep(const var_decl *var)
+  keep_wrt_regex_of_vars_to_keep(const var_decl_sptr& var)
   {
     if (!var)
       return false;
@@ -743,7 +743,7 @@  struct corpus::priv
   translation_units				members;
   string_tu_map_type				path_tu_map;
   vector<const function_decl*>			fns;
-  vector<const var_decl*>			vars;
+  vector<var_decl_sptr>			vars;
   functions_set				undefined_fns;
   functions					sorted_undefined_fns;
   variables_set				undefined_vars;
diff --git a/src/abg-corpus.cc b/src/abg-corpus.cc
index e9ba92ae..61c9b63d 100644
--- a/src/abg-corpus.cc
+++ b/src/abg-corpus.cc
@@ -190,7 +190,7 @@  corpus::exported_decls_builder::maybe_add_fn_to_exported_fns(function_decl* fn)
 /// @return true iff the variable was added to the set of exported
 /// variables.
 bool
-corpus::exported_decls_builder::maybe_add_var_to_exported_vars(const var_decl* var)
+corpus::exported_decls_builder::maybe_add_var_to_exported_vars(const var_decl_sptr& var)
 {
   if (!var->get_is_in_public_symbol_table())
     return false;
@@ -308,8 +308,12 @@  struct var_comp
 
     return first_name < second_name;
   }
-};
 
+  bool
+  operator()(const var_decl_sptr& first,
+	     const var_decl_sptr& second) const
+  {return operator()(first.get(), second.get());}
+};
 
 /// A comparison functor to compare elf_symbols for the purpose of
 /// sorting.
@@ -1411,7 +1415,7 @@  corpus::lookup_functions(const char* id) const
 ///
 /// @return the variable with ID @p id that was found or nil if none
 /// was found.
-const var_decl*
+const var_decl_sptr
 corpus::lookup_variable(const interned_string& id) const
 {
   exported_decls_builder_sptr b = get_exported_decls_builder();
diff --git a/src/abg-ctf-reader.cc b/src/abg-ctf-reader.cc
index 6879c6e0..9f551eab 100644
--- a/src/abg-ctf-reader.cc
+++ b/src/abg-ctf-reader.cc
@@ -502,7 +502,7 @@  public:
 	    add_decl_to_scope(var_declaration,
 			      ir_translation_unit->get_global_scope());
 	    var_declaration->set_is_in_public_symbol_table(true);
-	    add_var_to_exported_or_undefined_decls(var_declaration.get());
+	    add_var_to_exported_or_undefined_decls(var_declaration);
 	  }
 	else
 	  {
diff --git a/src/abg-dwarf-reader.cc b/src/abg-dwarf-reader.cc
index 1da1fd06..70a44674 100644
--- a/src/abg-dwarf-reader.cc
+++ b/src/abg-dwarf-reader.cc
@@ -16300,7 +16300,7 @@  build_ir_node_from_die(reader&	rdr,
 			rdr.var_decls_to_re_add_to_tree().push_back(m);
 		      }
 		    ABG_ASSERT(m->get_scope());
-		    rdr.add_var_to_exported_or_undefined_decls(m.get());
+		    rdr.add_var_to_exported_or_undefined_decls(m);
 		    result = m;
 		  }
 	      }
@@ -16318,7 +16318,7 @@  build_ir_node_from_die(reader&	rdr,
 	    ABG_ASSERT(v);
 	    ABG_ASSERT(v->get_scope());
 	    rdr.var_decls_to_re_add_to_tree().push_back(v);
-	    rdr.add_var_to_exported_or_undefined_decls(v.get());
+	    rdr.add_var_to_exported_or_undefined_decls(v);
 	  }
       }
       break;
diff --git a/src/abg-fe-iface.cc b/src/abg-fe-iface.cc
index e44d1126..e13ba68e 100644
--- a/src/abg-fe-iface.cc
+++ b/src/abg-fe-iface.cc
@@ -334,7 +334,7 @@  fe_iface::add_fn_to_exported_or_undefined_decls(const function_decl* fn)
 ///
 /// @param var the internal representation of the ABI of a variable.
 void
-fe_iface::add_var_to_exported_or_undefined_decls(const var_decl* var)
+fe_iface::add_var_to_exported_or_undefined_decls(const var_decl_sptr& var)
 {
   bool added = false;
   if (var)
diff --git a/src/abg-reader.cc b/src/abg-reader.cc
index 2d06302e..2928f3b3 100644
--- a/src/abg-reader.cc
+++ b/src/abg-reader.cc
@@ -5375,7 +5375,7 @@  build_class_decl(reader&		rdr,
 					    is_static,
 					    offset_in_bits);
 		      if (is_static)
-			rdr.add_var_to_exported_or_undefined_decls(v.get());
+			rdr.add_var_to_exported_or_undefined_decls(v);
 		      // Now let's record the fact that the data
 		      // member uses its type and that the class being
 		      // built uses the data member.
@@ -6469,7 +6469,7 @@  handle_var_decl(reader&	rdr,
 {
   decl_base_sptr decl = build_var_decl_if_not_suppressed(rdr, node,
 							 add_to_current_scope);
-  rdr.add_var_to_exported_or_undefined_decls(is_var_decl(decl).get());
+  rdr.add_var_to_exported_or_undefined_decls(is_var_decl(decl));
   return decl;
 }
 
diff --git a/src/abg-writer.cc b/src/abg-writer.cc
index 935ab08f..c198a532 100644
--- a/src/abg-writer.cc
+++ b/src/abg-writer.cc
@@ -2548,8 +2548,7 @@  write_translation_unit(write_context&		ctxt,
   if (const abigail::ir::corpus* abi = tu.get_corpus())
     for (auto undefined_var : abi->get_sorted_undefined_variables())
       {
-	var_decl_sptr v(const_cast<var_decl*>(undefined_var),
-			noop_deleter());
+	var_decl_sptr v = undefined_var;
 	if (v->get_translation_unit() != &tu || ctxt.decl_is_emitted(v))
 	  continue;
 
diff --git a/tools/abicompat.cc b/tools/abicompat.cc
index 718ddd9c..05ac2bdb 100644
--- a/tools/abicompat.cc
+++ b/tools/abicompat.cc
@@ -166,11 +166,11 @@  struct fn_change
 /// the differences found in the type of that variable.
 struct var_change
 {
-  const var_decl* decl = nullptr;
+  var_decl_sptr decl = nullptr;
   diff_sptr diff;
   bool reverse_direction = false;
 
-  var_change(const var_decl* var,
+  var_change(const var_decl_sptr& var,
 	     diff_sptr difference,
 	     bool reverse_dir)
     : decl(var),
@@ -542,7 +542,7 @@  compare_expected_against_provided_variables(diff_context_sptr&		ctxt,
     {
       interned_string var_id = expected_var->get_id();
       // ... against the variables exported by the library!
-      const var_decl* exported_var =
+      const var_decl_sptr exported_var =
 	reverse_direction
 	? app_corpus->lookup_variable(var_id)
 	: lib_corpus->lookup_variable(var_id);