abg-comparison.cc

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// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
// -*- Mode: C++ -*-
//
// Copyright (C) 2013-2023 Red Hat, Inc.
//
// Author: Dodji Seketeli
 
/// @file
///
/// This contains the implementation of the comparison engine of
/// libabigail.
 
#include <ctype.h>
#include <libgen.h>
#include <algorithm>
#include <sstream>
 
#include "abg-comparison-priv.h"
#include "abg-reporter-priv.h"
#include "abg-tools-utils.h"
 
namespace abigail
{
 
namespace comparison
{
 
///
///
///@defgroup DiffNode Internal Representation of the comparison engine
/// @{
///
/// @brief How changes are represented in libabigail's comparison engine.
///
///@par diff nodes
///
/// The internal representation of the comparison engine is basically
/// a graph of @ref instances of @ref diff node.  We refer to these
/// just as <em>diff nodes</em>.  A diff node represents a change
/// between two ABI artifacts represented by instances of types of the
/// abigail::ir namespace.  These two artifacts that are being
/// compared are called the <em>subjects of the diff</em>.
///
/// The types of that IR are in the abigail::comparison namespace.
///
///@par comparing diff nodes
///
/// Comparing two instances of @ref diff nodes amounts to comparing
/// the subject of the diff.  In other words, two @ref diff nodes are
/// equal if and only if their subjects are equal.  Thus, two @ref
/// diff nodes can have different memory addresses and yet be equal.
///
///@par diff reporting and context
///
/// A diff node can be serialized to an output stream to express, in
/// a human-readable textual form, the different changes that exist
/// between its two subjects.  This is done by invoking the
/// diff::report() method.  That reporting is controlled by several
/// parameters that are conceptually part of the context of the diff.
/// That context is materialized by an instance of the @ref
/// diff_context type.
///
/// Please note that the role of the instance(s) of @ref diff_context
/// is boreader than just controlling the reporting of @ref diff
/// nodes.  Basically, a @ref diff node itself is created following
/// behaviours that are controlled by a particular instance of
/// diff_context.  A diff node is created in a particular diff
/// context, so to speak.
///
/// @}
///
 
///
///@defgroup CanonicalDiff Canonical diff tree nodes
/// @{
///
/// @brief How equivalent diff nodes are quickly spotted.
///
/// @par Equivalence of diff nodes.
///
/// Each @ref diff node has a property named <em>Canonical Diff
/// Node</em>.  If \c D is a diff node, the canonical diff node of @c
/// D, noted @c C(D) is a particular diff node that is equal to @c D.
/// Thus, a fast way to compare two @ref diff node is to perform a
/// pointer comparison of their canonical diff nodes.
///
/// A set of equivalent @ref diff nodes is a set of diff nodes that
/// all have the same canonical node.  All the nodes of that set are
/// equal.
///
/// A canonical node is registereded for a given diff node by invoking
/// the method diff_context::initialize_canonical_diff().
///
/// Please note that the diff_context holds all the canonical diffs
/// that got registered through it.  Thus, the life time of all of
/// canonical diff objects is the same as the life time of the @ref
/// diff_context they relate to.
///
/// @}
///
 
// -----------------------------------------
// <private functions re-usable elsewhere>
// -----------------------------------------
/// Sort a map of enumerators by their value.
///
/// @param enumerators_map the map to sort.
///
/// @param sorted the resulting vector of sorted enumerators.
void
sort_enumerators(const string_enumerator_map& enumerators_map,
         enum_type_decl::enumerators& sorted)
{
  for (string_enumerator_map::const_iterator i = enumerators_map.begin();
       i != enumerators_map.end();
       ++i)
    sorted.push_back(i->second);
  enumerator_value_comp comp;
  std::sort(sorted.begin(), sorted.end(), comp);
}
 
/// Sort a map of changed enumerators.
///
/// @param enumerators_map the map to sort.
///
///@param output parameter.  The resulting sorted enumerators.
void
sort_changed_enumerators(const string_changed_enumerator_map& enumerators_map,
             changed_enumerators_type& sorted)
{
  for (string_changed_enumerator_map::const_iterator i =
     enumerators_map.begin();
       i != enumerators_map.end();
       ++i)
    sorted.push_back(i->second);
 
  changed_enumerator_comp comp;
  std::sort(sorted.begin(), sorted.end(), comp);
}
 
/// Sort a map of data members by the offset of their initial value.
///
/// @param data_members the map of changed data members to sort.
///
/// @param sorted the resulting vector of sorted changed data members.
void
sort_data_members(const string_decl_base_sptr_map &data_members,
          vector<decl_base_sptr>& sorted)
{
  sorted.reserve(data_members.size());
  for (string_decl_base_sptr_map::const_iterator i = data_members.begin();
       i != data_members.end();
       ++i)
    sorted.push_back(i->second);
 
  data_member_comp comp;
  std::sort(sorted.begin(), sorted.end(), comp);
}
 
/// Sort (in place) a vector of changed data members.
///
/// @param to_sort the vector to sort.
void
sort_changed_data_members(changed_var_sptrs_type& to_sort)
{
  data_member_comp comp;
  std::sort(to_sort.begin(), to_sort.end(), comp);
}
 
/// Sort an instance of @ref string_function_ptr_map map and stuff a
/// resulting sorted vector of pointers to function_decl.
///
/// @param map the map to sort.
///
/// @param sorted the resulting sorted vector.
void
sort_string_function_ptr_map(const string_function_ptr_map& map,
                 vector<function_decl*>& sorted)
{
  sorted.reserve(map.size());
  for (string_function_ptr_map::const_iterator i = map.begin();
       i != map.end();
       ++i)
    sorted.push_back(i->second);
 
  function_comp comp;
  std::sort(sorted.begin(), sorted.end(), comp);
}
 
/// Sort a map that's an instance of @ref
/// string_member_function_sptr_map and fill a vector of member
/// functions with the sorted result.
///
/// @param map the map to sort.
///
/// @param sorted the resulting sorted vector.
void
sort_string_member_function_sptr_map(const string_member_function_sptr_map& map,
                     class_or_union::member_functions& sorted)
{
  sorted.reserve(map.size());
  for (string_member_function_sptr_map::const_iterator i = map.begin();
       i != map.end();
       ++i)
    sorted.push_back(i->second);
 
  function_comp comp;
  std::sort(sorted.begin(), sorted.end(), comp);
}
 
/// Sort the values of a @ref string_function_decl_diff_sptr_map map
/// and store the result in a vector of @ref function_decl_diff_sptr
/// objects.
///
/// @param map the map whose values to store.
///
/// @param sorted the vector of function_decl_diff_sptr to store the
/// result of the sort into.
void
sort_string_function_decl_diff_sptr_map
(const string_function_decl_diff_sptr_map& map,
 function_decl_diff_sptrs_type& sorted)
{
  sorted.reserve(map.size());
  for (string_function_decl_diff_sptr_map::const_iterator i = map.begin();
       i != map.end();
       ++i)
    sorted.push_back(i->second);
  function_decl_diff_comp comp;
  std::sort(sorted.begin(), sorted.end(), comp);
}
 
/// Sort of an instance of @ref string_var_diff_sptr_map map.
///
/// @param map the input map to sort.
///
/// @param sorted the ouptut sorted vector of @ref var_diff_sptr.
/// It's populated with the sorted content.
void
sort_string_var_diff_sptr_map(const string_var_diff_sptr_map& map,
                  var_diff_sptrs_type& sorted)
{
  sorted.reserve(map.size());
  for (string_var_diff_sptr_map::const_iterator i = map.begin();
       i != map.end();
       ++i)
    sorted.push_back(i->second);
 
  var_diff_sptr_comp comp;
  std::sort(sorted.begin(), sorted.end(), comp);
}
 
/// Sort a map of string -> pointer to @ref elf_symbol.
///
/// The result is a vector of @ref elf_symbol_sptr sorted by the
/// name of the symbol.
///
/// @param map the map to sort.
///
/// @param sorted out parameter; the sorted vector of @ref
/// elf_symbol_sptr.
void
sort_string_elf_symbol_map(const string_elf_symbol_map& map,
               vector<elf_symbol_sptr>& sorted)
{
  for (string_elf_symbol_map::const_iterator i = map.begin();
       i!= map.end();
       ++i)
    sorted.push_back(i->second);
 
  elf_symbol_comp comp;
  std::sort(sorted.begin(), sorted.end(), comp);
}
 
/// Sort a map of string -> pointer to @ref var_decl.
///
/// The result is a vector of var_decl* sorted by the qualified name
/// of the variables.
///
/// @param map the map to sort.
///
/// @param sorted out parameter; the sorted vector of @ref var_decl.
void
sort_string_var_ptr_map(const string_var_ptr_map& map,
            vector<var_decl*>& sorted)
{
  for (string_var_ptr_map::const_iterator i = map.begin();
       i != map.end();
       ++i)
    sorted.push_back(i->second);
 
  var_comp comp;
  std::sort(sorted.begin(), sorted.end(), comp);
}
 
/// Sort the values of a string_var_diff_sptr_map and store the result
/// in a vector of var_diff_sptr.
///
/// @param map the map of changed data members to sort.
///
/// @param sorted the resulting vector of var_diff_sptr.
void
sort_string_data_member_diff_sptr_map(const string_var_diff_sptr_map& map,
                      var_diff_sptrs_type& sorted)
{
  sorted.reserve(map.size());
  for (string_var_diff_sptr_map::const_iterator i = map.begin();
       i != map.end();
       ++i)
    sorted.push_back(i->second);
  data_member_diff_comp comp;
  std::sort(sorted.begin(), sorted.end(), comp);
}
 
/// Sort the values of a unsigned_var_diff_sptr_map map and store the
/// result into a vector of var_diff_sptr.
///
/// @param map the map of changed data members to sort.
///
/// @param sorted the resulting vector of sorted var_diff_sptr.
void
sort_unsigned_data_member_diff_sptr_map(const unsigned_var_diff_sptr_map map,
                    var_diff_sptrs_type& sorted)
{
  sorted.reserve(map.size());
  for (unsigned_var_diff_sptr_map::const_iterator i = map.begin();
       i != map.end();
       ++i)
    sorted.push_back(i->second);
  data_member_diff_comp comp;
  std::sort(sorted.begin(), sorted.end(), comp);
}
 
/// Sort an map of string -> virtual member function into a vector of
/// virtual member functions.  The virtual member functions are sorted
/// by increasing order of their virtual index.
///
/// @param map the input map.
///
/// @param sorted the resulting sorted vector of virtual function
/// member.
void
sort_string_virtual_member_function_diff_sptr_map
(const string_function_decl_diff_sptr_map& map,
 function_decl_diff_sptrs_type& sorted)
{
  sorted.reserve(map.size());
  for (string_function_decl_diff_sptr_map::const_iterator i = map.begin();
       i != map.end();
       ++i)
    sorted.push_back(i->second);
 
  virtual_member_function_diff_comp comp;
  sort(sorted.begin(), sorted.end(), comp);
}
 
/// Sort a map ofg string -> @ref diff_sptr into a vector of @ref
/// diff_sptr.  The diff_sptr are sorted lexicographically wrt
/// qualified names of their first subjects.
///
/// @param map the map to sort.
///
/// @param sorted the resulting sorted vector.
void
sort_string_diff_sptr_map(const string_diff_sptr_map& map,
              diff_sptrs_type& sorted)
{
  sorted.reserve(map.size());
  for (string_diff_sptr_map::const_iterator i = map.begin();
       i != map.end();
       ++i)
    sorted.push_back(i->second);
 
  diff_comp comp;
  sort(sorted.begin(), sorted.end(), comp);
}
 
/// Sort a map ofg string -> @ref diff* into a vector of @ref
/// diff_ptr.  The diff_ptr are sorted lexicographically wrt
/// qualified names of their first subjects.
///
/// @param map the map to sort.
///
/// @param sorted the resulting sorted vector.
void
sort_string_diff_ptr_map(const string_diff_ptr_map& map,
              diff_ptrs_type& sorted)
{
  sorted.reserve(map.size());
  for (string_diff_ptr_map::const_iterator i = map.begin();
       i != map.end();
       ++i)
    sorted.push_back(i->second);
 
  diff_comp comp;
  sort(sorted.begin(), sorted.end(), comp);
}
 
/// Sort a map of string -> base_diff_sptr into a sorted vector of
/// base_diff_sptr.  The base_diff_sptr are sorted by increasing value
/// of their offset in their containing type.
///
/// @param map the input map to sort.
///
/// @param sorted the resulting sorted vector.
void
sort_string_base_diff_sptr_map(const string_base_diff_sptr_map& map,
                   base_diff_sptrs_type& sorted)
{
  for (string_base_diff_sptr_map::const_iterator i = map.begin();
       i != map.end();
       ++i)
    sorted.push_back(i->second);
  base_diff_comp comp;
  sort(sorted.begin(), sorted.end(), comp);
}
 
/// Lexicographically sort base specifications found
/// in instances of string_base_sptr_map.
void
sort_string_base_sptr_map(const string_base_sptr_map& m,
              class_decl::base_specs& sorted)
{
  for (string_base_sptr_map::const_iterator i = m.begin();
       i != m.end();
       ++i)
    sorted.push_back(i->second);
 
  base_spec_comp comp;
  std::sort(sorted.begin(), sorted.end(), comp);
}
 
/// Sort a map of @ref fn_parm_diff by the indexes of the function
/// parameters.
///
/// @param map the map to sort.
///
/// @param sorted the resulting sorted vector of changed function
/// parms.
void
sort_string_fn_parm_diff_sptr_map(const unsigned_fn_parm_diff_sptr_map& map,
                  vector<fn_parm_diff_sptr>&        sorted)
{
  sorted.reserve(map.size());
  for (unsigned_fn_parm_diff_sptr_map::const_iterator i = map.begin();
       i != map.end();
       ++i)
    sorted.push_back(i->second);
 
  fn_parm_diff_comp comp;
  std::sort(sorted.begin(), sorted.end(), comp);
}
 
/// Sort a map of changed function parameters by the indexes of the
/// function parameters.
///
/// @param map the map to sort.
///
/// @param sorted the resulting sorted vector of instances of @ref
/// fn_parm_diff_sptr
void
sort_string_fn_parm_diff_sptr_map(const string_fn_parm_diff_sptr_map&   map,
                  vector<fn_parm_diff_sptr>&        sorted)
{
  sorted.reserve(map.size());
  for (string_fn_parm_diff_sptr_map::const_iterator i = map.begin();
       i != map.end();
       ++i)
    sorted.push_back(i->second);
 
  fn_parm_diff_comp comp;
  std::sort(sorted.begin(), sorted.end(), comp);
}
 
/// Sort a map of string -> function parameters.
///
/// @param map the map to sort.
///
/// @param sorted the resulting sorted vector of
/// @ref vector<function_decl::parameter_sptr>
void
sort_string_parm_map(const string_parm_map& map,
             vector<function_decl::parameter_sptr>& sorted)
{
  for (string_parm_map::const_iterator i = map.begin();
       i != map.end();
       ++i)
    sorted.push_back(i->second);
 
  parm_comp comp;
  std::sort(sorted.begin(), sorted.end(), comp);
}
 
/// Sort the set of ABI artifacts contained in a @ref
/// artifact_sptr_set_type.
///
/// @param set the set of ABI artifacts to sort.
///
/// @param output parameter the vector containing the sorted ABI
/// artifacts.
void
sort_artifacts_set(const artifact_sptr_set_type& set,
           vector<type_or_decl_base_sptr>& sorted)
{
 
  for (artifact_sptr_set_type::const_iterator it = set.begin();
       it != set.end();
       ++it)
    sorted.push_back(*it);
 
  type_or_decl_base_comp comp;
  std::sort(sorted.begin(), sorted.end(), comp);
}
 
/// Sort a map of string to type_base_sptr entities.
///
/// The entries are sorted based on the lexicographic order of the
/// pretty representation of the type_sptr_sptr.  The sorted result is
/// put in a vector of type_base_sptr.
///
/// @param map the map to sort.
///
/// @param sorted the resulting vector of type_base_sptr
/// lexicographically sorted using their pretty representation.
void
sort_string_type_base_sptr_map(string_type_base_sptr_map& map,
                   vector<type_base_sptr>& sorted)
{
  for (string_type_base_sptr_map::const_iterator i = map.begin();
       i != map.end();
       ++i)
    sorted.push_back(i->second);
 
  type_or_decl_base_comp comp;
  std::sort(sorted.begin(), sorted.end(), comp);
}
 
/// Return the first underlying type that is not a qualified type.
/// @param t the qualified type to consider.
///
/// @return the first underlying type that is not a qualified type, or
/// NULL if t is NULL.
type_base_sptr
get_leaf_type(qualified_type_def_sptr t)
{
  if (!t)
    return type_base_sptr();
 
  type_base_sptr ut = t->get_underlying_type();
  qualified_type_def_sptr qut = dynamic_pointer_cast<qualified_type_def>(ut);
 
  if (!qut)
    return ut;
  return get_leaf_type(qut);
}
 
/// Tests if a given diff node is to represent the changes between two
/// gobal decls.
///
/// @param d the diff node to consider.
///
/// @return true iff @p d represents the changes between two global
/// decls.
bool
is_diff_of_global_decls(const diff* d)
{
  ABG_ASSERT(d != 0);
 
  if (d == 0)
    return false;
 
  type_or_decl_base_sptr first = d->first_subject();
  ABG_ASSERT(first);
 
  type_or_decl_base_sptr second = d->first_subject();
  ABG_ASSERT(second);
 
  if (decl_base_sptr decl = is_decl(first))
    if (is_at_global_scope(decl))
      if ((decl = is_decl(second)))
    if (is_at_global_scope(decl))
      return true;
 
  return false;
}
 
// -----------------------------------------
// </private functions re-usable elsewhere>
// -----------------------------------------
 
/// The overloaded or operator for @ref visiting_kind.
visiting_kind
operator|(visiting_kind l, visiting_kind r)
{return static_cast<visiting_kind>(static_cast<unsigned>(l)
                   | static_cast<unsigned>(r));}
 
/// The overloaded and operator for @ref visiting_kind.
visiting_kind
operator&(visiting_kind l, visiting_kind r)
{
  return static_cast<visiting_kind>(static_cast<unsigned>(l)
                    & static_cast<unsigned>(r));
}
 
/// The overloaded 'bit inversion' operator for @ref visiting_kind.
visiting_kind
operator~(visiting_kind l)
{return static_cast<visiting_kind>(~static_cast<unsigned>(l));}
 
/// Test if a diff node is about differences between types.
///
/// @param diff the diff node to test.
///
/// @return a pointer to the actual type_diff_base* that @p diff
/// extends, iff it is about differences between types.
const type_diff_base*
is_type_diff(const diff* diff)
{return dynamic_cast<const type_diff_base*>(diff);}
 
/// Test if a diff node is about differences between declarations.
///
/// @param diff the diff node to test.
///
/// @return a pointer to the actual decl_diff_base @p diff extends,
/// iff it is about differences between declarations.
const decl_diff_base*
is_decl_diff(const diff* diff)
{return dynamic_cast<const decl_diff_base*>(diff);}
 
/// Test if a diff node is a @ref class_diff node.
///
/// @param diff the diff node to consider.
///
/// @return a non-nil pointer to a @ref class_diff iff @p diff is a
/// @ref class_diff node.
const class_diff*
is_class_diff(const diff* diff)
{return dynamic_cast<const class_diff*>(diff);}
 
/// Test if a diff node is a @ref enum_diff node.
///
/// @param diff the diff node to consider.
///
/// @return a non-nil pointer to ad @ref enum_diff node iff @p diff is
/// a @ref enum_diff node.
const enum_diff*
is_enum_diff(const diff *diff)
{return dynamic_cast<const enum_diff*>(diff);}
 
/// Test if a diff node is a @ref union_diff node.
///
/// @param diff the diff node to consider.
///
/// @return a non-nil pointer to a @ref union_diff iff @p diff is a
/// @ref union_diff node.
const union_diff*
is_union_diff(const diff* diff)
{return dynamic_cast<const union_diff*>(diff);}
 
/// Test if a diff node is a @ref class_or_union_diff node.
///
/// @param d the diff node to consider.
///
/// @return a non-nil pointer to the @ref class_or_union_diff denoted
/// by @p d iff @p d is a @ref class_or_union_diff.
const class_or_union_diff*
is_class_or_union_diff(const diff* d)
{return dynamic_cast<const class_or_union_diff*>(d);}
 
/// Test if a diff node is a @ref class_or_union_diff between two
/// anonymous classes or unions.
///
/// @param d the diff node to consider.
///
/// @return a non-nil pointer to the @ref class_or_union_diff iff @p
/// denoted by @p d iff @p is pointer to an anonymous class or union
/// diff.
const class_or_union_diff*
is_anonymous_class_or_union_diff(const diff* d)
{
  if (const class_or_union_diff *dif = is_class_or_union_diff(d))
    if (dif->first_class_or_union()->get_is_anonymous())
      return dif;
  return 0;
}
 
/// Test if a diff node is a @ref typedef_diff node.
///
/// @param diff the diff node to consider.
///
/// @return a non-nil pointer to a @ref typedef_diff iff @p diff is a
/// @ref typedef_diff node.
const typedef_diff*
is_typedef_diff(const diff *diff)
{return dynamic_cast<const typedef_diff*>(diff);}
 
/// Test if a diff node is a @ref subrange_diff node.
///
/// @param diff the diff node to consider.
///
/// @return a non-nil pointer to a @ref subrange_diff iff @p diff is a
/// @ref subrange_diff node.
const subrange_diff*
is_subrange_diff(const diff* diff)
{return dynamic_cast<const subrange_diff*>(diff);}
 
/// Test if a diff node is a @ref array_diff node.
///
/// @param diff the diff node to consider.
///
/// @return a non-nil pointer to a @ref array_diff iff @p diff is a
/// @ref array_diff node.
const array_diff*
is_array_diff(const diff* diff)
{return dynamic_cast<const array_diff*>(diff);}
 
/// Test if a diff node is a @ref function_type_diff node.
///
/// @param diff the diff node to consider.
///
/// @return a non-nil pointer to a @ref function_type_diff iff @p diff is a
/// @ref function_type_diff node.
const function_type_diff*
is_function_type_diff(const diff* diff)
{return dynamic_cast<const function_type_diff*>(diff);}
 
/// Test if a given diff node carries a function type change with
/// local changes.
///
/// @param diff the diff node to consider.
///
/// @return a non-nil pointer to a @ref function_type_diff iff @p diff
/// is a function_type_diff node that carries a local change.
const function_type_diff*
is_function_type_diff_with_local_changes(const diff* diff)
{
  if (const function_type_diff* d = is_function_type_diff(diff))
    if (d->has_local_changes())
      return d;
 
  return 0;
}
 
/// Test if a diff node is about differences between variables.
///
/// @param diff the diff node to test.
///
/// @return a pointer to the actual var_diff that @p diff is a type
/// of, iff it is about differences between variables.
const var_diff*
is_var_diff(const diff* diff)
{
  const var_diff* d = dynamic_cast<const var_diff*>(diff);
  if (d)
    ABG_ASSERT(is_decl_diff(diff));
  return d;
}
 
/// Test if a diff node is about differences between functions.
///
/// @param diff the diff node to test.
///
/// @return a pointer to the actual var_diff that @p diff is a type
/// of, iff it is about differences between variables.
const function_decl_diff*
is_function_decl_diff(const diff* diff)
{
  const function_decl_diff *d = dynamic_cast<const function_decl_diff*>(diff);
  if (d)
    ABG_ASSERT(is_decl_diff(diff));
  return d;
}
 
/// Test if a diff node is about differences between two pointers.
///
/// @param diff the diff node to consider.
///
/// @return the @p diff converted into an instance of @ref
/// pointer_diff iff @p diff is about differences between two
/// pointers.
const pointer_diff*
is_pointer_diff(const diff* diff)
{return dynamic_cast<const pointer_diff*>(diff);}
 
/// Test if a diff node is about differences between two references.
///
/// @param diff the diff node to consider.
///
/// @return the @p diff converted into an instance of @ref
/// reference_diff iff @p diff is about differences between two
/// references.
const reference_diff*
is_reference_diff(const diff* diff)
{return dynamic_cast<const reference_diff*>(diff);}
 
/// Test if a diff node is about differences between two qualified
/// types.
///
/// @param diff the diff node to consider.
///
/// @return @p diff converted into an instance of @ref
/// qualified_type_diff iff @p diff is about differences between two
/// qualified types.
const qualified_type_diff*
is_qualified_type_diff(const diff* diff)
{return dynamic_cast<const qualified_type_diff*>(diff);}
 
/// Test if a diff node is a reference or pointer diff node to a
/// change that is neither basic type change nor distinct type change.
///
/// Note that this function also works on diffs of typedefs of
/// reference or pointer.
///
/// @param diff the diff node to consider.
///
/// @return true iff @p diff is a eference or pointer diff node to a
/// change that is neither basic type change nor distinct type change.
bool
is_reference_or_ptr_diff_to_non_basic_nor_distinct_types(const diff* diff)
{
  diff = peel_typedef_diff(diff);
  if (const reference_diff* d = is_reference_diff(diff))
    {
      diff = peel_reference_diff(d);
      if (is_diff_of_basic_type(diff) || is_distinct_diff(diff))
    return false;
      return true;
    }
  else if (const pointer_diff *d = is_pointer_diff(diff))
    {
      diff = peel_pointer_diff(d);
      if (is_diff_of_basic_type(diff) || is_distinct_diff(diff))
    return false;
      return true;
    }
 
  return false;
}
 
/// Test if a diff node is about differences between two function
/// parameters.
///
/// @param diff the diff node to consider.
///
/// @return the @p diff converted into an instance of @ref
/// reference_diff iff @p diff is about differences between two
/// function parameters.
const fn_parm_diff*
is_fn_parm_diff(const diff* diff)
{return dynamic_cast<const fn_parm_diff*>(diff);}
 
/// Test if a diff node is about differences between two base class
/// specifiers.
///
/// @param diff the diff node to consider.
///
/// @return the @p diff converted into an instance of @ref base_diff
/// iff @p diff is about differences between two base class
/// specifiers.
const base_diff*
is_base_diff(const diff* diff)
{return dynamic_cast<const base_diff*>(diff);}
 
/// Test if a diff node is about differences between two diff nodes of
/// different kinds.
///
/// @param diff the diff node to consider.
///
/// @return the @p diff converted into an instance of @ref
/// distintc_diff iff @p diff is about differences between two diff
/// nodes of different kinds.
const distinct_diff*
is_distinct_diff(const diff *diff)
{return dynamic_cast<const distinct_diff*>(diff);}
 
/// Test if a diff node is a @ref corpus_diff node.
///
/// @param diff the diff node to consider.
///
/// @return a non-nil pointer to a @ref corpus_diff iff @p diff is a
/// @ref corpus_diff node.
const corpus_diff*
is_corpus_diff(const diff* diff)
{return dynamic_cast<const corpus_diff*>(diff);}
 
/// Test if a diff node is a child node of a function parameter diff node.
///
/// @param diff the diff node to test.
///
/// @return true iff @p diff is a child node of a function parameter
/// diff node.
bool
is_child_node_of_function_parm_diff(const diff* diff)
{return diff && is_fn_parm_diff(diff->parent_node());}
 
/// Test if a diff node is a child node of a base diff node.
///
/// @param diff the diff node to test.
///
/// @return true iff @p diff is a child node of a base diff node.
bool
is_child_node_of_base_diff(const diff* diff)
{return diff && is_base_diff(diff->parent_node());}
 
/// The default traverse function.
///
/// @return true.
bool
diff_traversable_base::traverse(diff_node_visitor&)
{return true;}
 
diff_context::diff_context()
  : priv_(new diff_context::priv)
{
  // Setup all the diff output filters we have.
  filtering::filter_base_sptr f;
 
  f.reset(new filtering::harmless_harmful_filter);
  add_diff_filter(f);
 
  // f.reset(new filtering::harmless_filter);
  // add_diff_filter(f);
 
  // f.reset(new filtering::harmful_filter);
  // add_diff_filter(f);
}
 
diff_context::~diff_context() = default;
 
/// Test if logging was requested.
///
/// @return true iff logging was requested.
bool
diff_context::do_log() const
{return priv_->do_log_;}
 
/// Set logging as requested.
///
/// @param f the flag
void
diff_context::do_log(bool f)
{priv_->do_log_ = f;}
 
/// Set the corpus diff relevant to this context.
///
/// @param d the corpus_diff we are interested in.
void
diff_context::set_corpus_diff(const corpus_diff_sptr& d)
{priv_->corpus_diff_ = d;}
 
/// Get the corpus diff for the current context.
///
/// @return the corpus diff of this context.
const corpus_diff_sptr&
diff_context::get_corpus_diff() const
{return priv_->corpus_diff_;}
 
/// Getter for the first corpus of the corpus diff of the current context.
///
/// @return the first corpus of the corpus diff of the current
/// context, if no corpus diff is associated to the context.
corpus_sptr
diff_context::get_first_corpus() const
{
  if (priv_->corpus_diff_)
    return priv_->corpus_diff_->first_corpus();
  return corpus_sptr();
}
 
/// Getter for the second corpus of the corpus diff of the current
/// context.
///
/// @return the second corpus of the corpus diff of the current
/// context, if no corpus diff is associated to the context.
corpus_sptr
diff_context::get_second_corpus() const
{
  if (priv_->corpus_diff_)
    return priv_->corpus_diff_->second_corpus();
  return corpus_sptr();
}
 
/// Getter of the reporter to be used in this context.
///
/// @return the reporter to be used in this context.
reporter_base_sptr
diff_context::get_reporter() const
{
  if (!priv_->reporter_)
    {
      if (show_leaf_changes_only())
    priv_->reporter_.reset(new leaf_reporter);
      else
    priv_->reporter_.reset(new default_reporter);
    }
  ABG_ASSERT(priv_->reporter_);
  return priv_->reporter_;
}
 
/// Setter of the reporter to be used in this context.
///
/// @param r the reporter to be used in this context.
void
diff_context::set_reporter(reporter_base_sptr& r)
{priv_->reporter_ = r;}
 
/// Tests if the current diff context already has a diff for two decls.
///
/// @param first the first decl to consider.
///
/// @param second the second decl to consider.
///
/// @return a pointer to the diff for @p first @p second if found,
/// null otherwise.
diff_sptr
diff_context::has_diff_for(const type_or_decl_base_sptr first,
               const type_or_decl_base_sptr second) const
{
  types_or_decls_diff_map_type::const_iterator i =
    priv_->types_or_decls_diff_map.find(std::make_pair(first, second));
  if (i != priv_->types_or_decls_diff_map.end())
    return i->second;
  return diff_sptr();
}
 
/// Tests if the current diff context already has a diff for two types.
///
/// @param first the first type to consider.
///
/// @param second the second type to consider.
///
/// @return a pointer to the diff for @p first @p second if found,
/// null otherwise.
diff_sptr
diff_context::has_diff_for_types(const type_base_sptr first,
                  const type_base_sptr second) const
{return has_diff_for(first, second);}
 
/// Tests if the current diff context already has a given diff.
///
///@param d the diff to consider.
///
/// @return a pointer to the diff found for @p d
const diff*
diff_context::has_diff_for(const diff* d) const
{return has_diff_for(d->first_subject(), d->second_subject()).get();}
 
/// Tests if the current diff context already has a given diff.
///
///@param d the diff to consider.
///
/// @return a pointer to the diff found for @p d
diff_sptr
diff_context::has_diff_for(const diff_sptr d) const
{return has_diff_for(d->first_subject(), d->second_subject());}
 
/// Getter for the bitmap that represents the set of categories that
/// the user wants to see reported.
///
/// @return a bitmap that represents the set of categories that the
/// user wants to see reported.
diff_category
diff_context::get_allowed_category() const
{return priv_->allowed_category_;}
 
/// Setter for the bitmap that represents the set of categories that
/// the user wants to see reported.
///
/// @param c a bitmap that represents the set of categories that the
/// user wants to see represented.
void
diff_context::set_allowed_category(diff_category c)
{priv_->allowed_category_ = c;}
 
/// Setter for the bitmap that represents the set of categories that
/// the user wants to see reported
///
/// This function perform a bitwise or between the new set of
/// categories and the current ones, and then sets the current
/// categories to the result of the or.
///
/// @param c a bitmap that represents the set of categories that the
/// user wants to see represented.
void
diff_context::switch_categories_on(diff_category c)
{priv_->allowed_category_ = priv_->allowed_category_ | c;}
 
/// Setter for the bitmap that represents the set of categories that
/// the user wants to see reported
///
/// This function actually unsets bits from the current categories.
///
/// @param c a bitmap that represents the set of categories to unset
/// from the current categories.
void
diff_context::switch_categories_off(diff_category c)
{priv_->allowed_category_ = priv_->allowed_category_ & ~c;}
 
/// Add a diff for two decls to the cache of the current diff_context.
///
/// Doing this allows to later find the added diff from its two
/// subject decls.
///
/// @param first the first decl to consider.
///
/// @param second the second decl to consider.
///
/// @param the diff to add.
void
diff_context::add_diff(type_or_decl_base_sptr first,
               type_or_decl_base_sptr second,
               const diff_sptr d)
{priv_->types_or_decls_diff_map[std::make_pair(first, second)] = d;}
 
/// Add a diff tree node to the cache of the current diff_context
///
/// @param d the diff tree node to add.
void
diff_context::add_diff(const diff* d)
{
  if (d)
    {
      diff_sptr dif(const_cast<diff*>(d), noop_deleter());
      add_diff(d->first_subject(), d->second_subject(), dif);
    }
}
 
/// Add a diff tree node to the cache of the current diff_context
///
/// @param d the diff tree node to add.
void
diff_context::add_diff(const diff_sptr d)
{
  if (d)
      add_diff(d->first_subject(), d->second_subject(), d);
}
 
/// Getter for the @ref CanonicalDiff "canonical diff node" for the
/// @ref diff represented by their two subjects.
///
/// @param first the first subject of the diff.
///
/// @param second the second subject of the diff.
///
/// @return the canonical diff for the diff node represented by the
/// two diff subjects @p first and @p second.  If no canonical diff
/// node was registered for these subjects, then a nil node is
/// returned.
diff_sptr
diff_context::get_canonical_diff_for(const type_or_decl_base_sptr first,
                     const type_or_decl_base_sptr second) const
{return has_diff_for(first, second);}
 
/// Getter for the @ref CanonicalDiff "canonical diff node" for the
/// @ref diff represented by the two subjects of a given diff node.
///
/// @param d the diff node to get the canonical node for.
///
/// @return the canonical diff for the diff node represented by the
/// two diff subjects of @p d.  If no canonical diff node was
/// registered for these subjects, then a nil node is returned.
diff_sptr
diff_context::get_canonical_diff_for(const diff_sptr d) const
{return has_diff_for(d);}
 
/// Setter for the @ref CanonicalDiff "canonical diff node" for the
/// @ref diff represented by their two subjects.
///
/// @param first the first subject of the diff.
///
/// @param second the second subject of the diff.
///
/// @param d the new canonical diff.
void
diff_context::set_canonical_diff_for(const type_or_decl_base_sptr first,
                     const type_or_decl_base_sptr second,
                     const diff_sptr d)
{
  ABG_ASSERT(d);
  if (!has_diff_for(first, second))
    {
      add_diff(first, second, d);
      priv_->canonical_diffs.push_back(d);
    }
}
 
/// If there is is a @ref CanonicalDiff "canonical diff node"
/// registered for two diff subjects, return it.  Otherwise, register
/// a canonical diff node for these two diff subjects and return it.
///
/// @param first the first subject of the diff.
///
/// @param second the second subject of the diff.
///
/// @param d the new canonical diff node.
///
/// @return the canonical diff node.
diff_sptr
diff_context::set_or_get_canonical_diff_for(const type_or_decl_base_sptr first,
                        const type_or_decl_base_sptr second,
                        const diff_sptr canonical_diff)
{
  ABG_ASSERT(canonical_diff);
 
  diff_sptr canonical = get_canonical_diff_for(first, second);
  if (!canonical)
    {
      canonical = canonical_diff;
      set_canonical_diff_for(first, second, canonical);
    }
  return canonical;
}
 
/// Set the canonical diff node property of a given diff node
/// appropriately.
///
/// For a given diff node that has no canonical diff node, retrieve
/// the canonical diff node (by looking at its diff subjects and at
/// the current context) and set the canonical diff node property of
/// the diff node to that canonical diff node.  If no canonical diff
/// node has been registered to the diff context for the subjects of
/// the diff node then, register the canonical diff node as being the
/// diff node itself; and set its canonical diff node property as
/// such.  Otherwise, if the diff node already has a canonical diff
/// node, do nothing.
///
/// @param diff the diff node to initialize the canonical diff node
/// property for.
void
diff_context::initialize_canonical_diff(const diff_sptr diff)
{
  if (diff->get_canonical_diff() == 0)
    {
      diff_sptr canonical =
    set_or_get_canonical_diff_for(diff->first_subject(),
                      diff->second_subject(),
                      diff);
      diff->set_canonical_diff(canonical.get());
    }
}
 
/// Add a diff node to the set of diff nodes that are kept alive for
/// the life time of the current instance of diff_context.
///
/// Note that diff added to the diff cache are kept alive as well, and
/// don't need to be passed to this function to be kept alive.
///
/// @param d the diff node to be kept alive during the life time of
/// the current instance of @ref diff_context.
void
diff_context::keep_diff_alive(diff_sptr& d)
{priv_->live_diffs_.insert(d);}
 
/// Test if a diff node has been traversed.
///
/// @param d the diff node to consider.
///
/// @return the first diff node against which @p d is redundant.
diff*
diff_context::diff_has_been_visited(const diff* d) const
{
  const diff* canonical = d->get_canonical_diff();
  ABG_ASSERT(canonical);
 
  size_t ptr_value = reinterpret_cast<size_t>(canonical);
  pointer_map::iterator it = priv_->visited_diff_nodes_.find(ptr_value);
  if (it != priv_->visited_diff_nodes_.end())
    return reinterpret_cast<diff*>(it->second);
  else
    return 0;
}
 
/// Test if a diff node has been traversed.
///
/// @param d the diff node to consider.
///
/// @return the first diff node against which @p d is redundant.
diff_sptr
diff_context::diff_has_been_visited(const diff_sptr d) const
{
  diff_sptr diff(diff_has_been_visited(d.get()));
  return diff;
}
 
/// Mark a diff node as traversed by a traversing algorithm.
///
/// Actually, it's the @ref CanonicalDiff "canonical diff" of this
/// node that is marked as traversed.
///
/// Subsequent invocations of diff_has_been_visited() on the diff node
/// will yield true.
void
diff_context::mark_diff_as_visited(const diff* d)
{
  if (diff_has_been_visited(d))
    return;
 
  const diff* canonical = d->get_canonical_diff();
  ABG_ASSERT(canonical);
 
   size_t canonical_ptr_value = reinterpret_cast<size_t>(canonical);
   size_t diff_ptr_value = reinterpret_cast<size_t>(d);
   priv_->visited_diff_nodes_[canonical_ptr_value] = diff_ptr_value;
}
 
/// Unmark all the diff nodes that were marked as being traversed.
void
diff_context::forget_visited_diffs()
{priv_->visited_diff_nodes_.clear();}
 
/// This sets a flag that, if it's true, then during the traversing of
/// a diff nodes tree each node is visited at most once.
///
/// @param f if true then during the traversing of a diff nodes tree
/// each node is visited at most once.
///
void
diff_context::forbid_visiting_a_node_twice(bool f)
{priv_->forbid_visiting_a_node_twice_ = f;}
 
/// This function sets a flag os that if @ref
///  forbid_visiting_a_node_twice() returns true, then each time the
///  node visitor starts visiting a new interface, it resets the
///  memory the systems has about already visited node.
///
///  @param f the flag to set.
void
diff_context::forbid_visiting_a_node_twice_per_interface(bool f)
{priv_->reset_visited_diffs_for_each_interface_ = f;}
 
/// Return a flag that, if true, then during the traversing of a diff
/// nodes tree each node is visited at most once.
///
/// @return the boolean flag.
bool
diff_context::visiting_a_node_twice_is_forbidden() const
{return priv_->forbid_visiting_a_node_twice_;}
 
/// Return a flag that, if true, then during the traversing of a diff
/// nodes tree each node is visited at most once, while visiting the
/// diff tree underneath a given interface (public function or
/// variable).  Each time a new interface is visited, the nodes
/// visited while visiting previous interfaces can be visited again.
///
/// @return the boolean flag.
///
/// @return the boolean flag.
bool
diff_context::visiting_a_node_twice_is_forbidden_per_interface() const
{
  return (priv_->forbid_visiting_a_node_twice_
      && priv_->reset_visited_diffs_for_each_interface_);
}
 
/// Getter for the diff tree nodes filters to apply to diff sub-trees.
///
/// @return the vector of tree filters to apply to diff sub-trees.
const filtering::filters&
diff_context::diff_filters() const
{return priv_->filters_;}
 
/// Setter for the diff filters to apply to a given diff sub-tree.
///
/// @param f the new diff filter to add to the vector of diff filters
/// to apply to diff sub-trees.
void
diff_context::add_diff_filter(filtering::filter_base_sptr f)
{priv_->filters_.push_back(f);}
 
/// Apply the diff filters to a given diff sub-tree.
///
/// If the current context is instructed to filter out some categories
/// then this function walks the given sub-tree and categorizes its
/// nodes by using the filters held by the context.
///
/// @param diff the diff sub-tree to apply the filters to.
void
diff_context::maybe_apply_filters(diff_sptr diff)
{
  if (!diff)
    return;
 
  if (get_allowed_category() == EVERYTHING_CATEGORY)
    return;
 
  if (!diff->has_changes())
    return;
 
  for (filtering::filters::const_iterator i = diff_filters().begin();
       i != diff_filters().end();
       ++i)
    {
      tools_utils::timer t;
      if (do_log())
    {
      std::cerr << "applying a filter to diff '"
            << diff->get_pretty_representation()
            << "'...\n";
      t.start();
    }
 
      filtering::apply_filter(*i, diff);
 
      if (do_log())
    {
      t.stop();
      std::cerr << "filter applied!:" << t << "\n";
 
      std::cerr << "propagating categories for the same diff node ... \n";
      t.start();
    }
 
      propagate_categories(diff);
 
      if (do_log())
    {
      t.stop();
      std::cerr << "category propagated!: " << t << "\n";
    }
    }
 
 }
 
/// Apply the diff filters to the diff nodes of a @ref corpus_diff
/// instance.
///
/// If the current context is instructed to filter out some categories
/// then this function walks the diff tree and categorizes its nodes
/// by using the filters held by the context.
///
/// @param diff the corpus diff to apply the filters to.
void
diff_context::maybe_apply_filters(corpus_diff_sptr diff)
{
 
  if (!diff || !diff->has_changes())
    return;
 
  for (filtering::filters::const_iterator i = diff_filters().begin();
       i != diff_filters().end();
       ++i)
    {
      filtering::apply_filter(**i, diff);
      propagate_categories(diff);
    }
}
 
/// Getter for the vector of suppressions that specify which diff node
/// reports should be dropped on the floor.
///
/// @return the set of suppressions.
const suppressions_type&
diff_context::suppressions() const
{return priv_->suppressions_;}
 
/// Getter for the vector of suppressions that specify which diff node
/// reports should be dropped on the floor.
///
/// @return the set of suppressions.
suppr::suppressions_type&
diff_context::suppressions()
{
  // Invalidate negated and direct suppressions caches that are built
  // from priv_->suppressions_;
  priv_->negated_suppressions_.clear();
  priv_->direct_suppressions_.clear();
  return priv_->suppressions_;
}
 
/// Getter of the negated suppression specifications that are
/// comprised in the general vector of suppression specifications
/// returned by diff_context::suppressions().
///
/// Note that the first invocation of this function scans the vector
/// returned by diff_context::suppressions() and caches the negated
/// suppressions from there.
///
/// Subsequent invocations of this function just return the cached
/// negated suppressions.
///
/// @return the negated suppression specifications stored in this diff
/// context.
const suppr::suppressions_type&
diff_context::negated_suppressions() const
{
  if (priv_->negated_suppressions_.empty())
    for (auto s : suppressions())
      if (is_negated_suppression(s))
    priv_->negated_suppressions_.push_back(s);
 
  return priv_->negated_suppressions_;
}
 
/// Getter of the direct suppression specification (those that are
/// not negated) comprised in the general vector of suppression
/// specifications returned by diff_context::suppression().
///
/// Note that the first invocation of this function scans the vector
/// returned by diff_context::suppressions() and caches the direct
/// suppressions from there.
///
/// Subsequent invocations of this function just return the cached
/// direct suppressions.
///
/// @return the direct suppression specifications.
const suppr::suppressions_type&
diff_context::direct_suppressions() const
{
   if (priv_->direct_suppressions_.empty())
    {
      for (auto s : suppressions())
    if (!is_negated_suppression(s))
      priv_->direct_suppressions_.push_back(s);
    }
   return priv_->direct_suppressions_;
}
 
/// Add a new suppression specification that specifies which diff node
/// reports should be dropped on the floor.
///
/// @param suppr the new suppression specification to add to the
/// existing set of suppressions specifications of the diff context.
void
diff_context::add_suppression(const suppression_sptr suppr)
{
  priv_->suppressions_.push_back(suppr);
  // Invalidate negated and direct suppressions caches that are built
  // from priv_->suppressions_;
  priv_->negated_suppressions_.clear();
  priv_->direct_suppressions_.clear();
}
 
/// Add new suppression specifications that specify which diff node
/// reports should be dropped on the floor.
///
/// @param supprs the new suppression specifications to add to the
/// existing set of suppression specifications of the diff context.
void
diff_context::add_suppressions(const suppressions_type& supprs)
{
  priv_->suppressions_.insert(priv_->suppressions_.end(),
                  supprs.begin(), supprs.end());
}
 
/// Test if it's requested to perform diff node categorization.
///
/// @return true iff it's requested to perform diff node
/// categorization.
bool
diff_context::perform_change_categorization() const
{return priv_->perform_change_categorization_;}
 
/// Request change categorization or not.
///
/// @param f true iff change categorization is requested.
void
diff_context::perform_change_categorization(bool f)
{priv_->perform_change_categorization_ = f;}
 
/// Set the flag that indicates if the diff using this context should
/// show only leaf changes or not.
///
/// @param f the new value of the flag that indicates if the diff
/// using this context should show only leaf changes or not.
void
diff_context::show_leaf_changes_only(bool f)
{
  // This function can be called only if the reporter hasn't yet been
  // created.  Once it's been created, we are supposed to live with
  // it.
  ABG_ASSERT(priv_->reporter_ == 0);
  priv_->leaf_changes_only_ = f;
}
 
/// Get the flag that indicates if the diff using this context should
/// show only leaf changes or not.
///
/// @return the value of the flag that indicates if the diff using
/// this context should show only leaf changes or not.
bool
diff_context::show_leaf_changes_only() const
{return priv_->leaf_changes_only_;}
 
/// Get the flag that indicates if the diff reports using this context
/// should show sizes and offsets in an hexadecimal base or not.  If
/// not, then they are to be shown in a decimal base.
///
/// @return true iff sizes and offsets are to be shown in an
/// hexadecimal base.
bool
diff_context::show_hex_values() const
{return priv_->hex_values_;}
 
/// Set the flag that indicates if diff reports using this context
/// should show sizes and offsets in an hexadecimal base or not.  If
/// not, then they are to be shown in a decimal base.
///
/// @param f if true then sizes and offsets are to be shown in an
/// hexadecimal base.
void
diff_context::show_hex_values(bool f)
{priv_->hex_values_ = f;}
 
/// Get the flag that indicates if diff reports using this context
/// should show sizes and offsets in bits, rather than bytes.
///
/// @return true iff sizes and offsets are to be shown in bits.
/// Otherwise they are to be shown in bytes.
bool
diff_context::show_offsets_sizes_in_bits() const
{return priv_->show_offsets_sizes_in_bits_;}
 
/// Set the flag that indicates if diff reports using this context
/// should show sizes and offsets in bits, rather than bytes.
///
/// @param f if true then sizes and offsets are to be shown in bits.
/// Otherwise they are to be shown in bytes.
void
diff_context::show_offsets_sizes_in_bits(bool f)
{priv_->show_offsets_sizes_in_bits_ = f;}
 
/// Set a flag saying if offset changes should be reported in a
/// relative way.  That is, if the report should say how of many bits
/// a class/struct data member did move.
///
/// @param f the new boolean value of the flag.
void
diff_context::show_relative_offset_changes(bool f)
{priv_->show_relative_offset_changes_ = f;}
 
/// Get the flag saying if offset changes should be reported in a
/// relative way.  That is, if the report should say how of many bits
/// a class/struct data member did move.
///
/// @return the boolean value of the flag.
bool
diff_context::show_relative_offset_changes(void)
{return priv_->show_relative_offset_changes_;}
 
/// Set a flag saying if the comparison module should only show the
/// diff stats.
///
/// @param f the flag to set.
void
diff_context::show_stats_only(bool f)
{priv_->show_stats_only_ = f;}
 
/// Test if the comparison module should only show the diff stats.
///
/// @return true if the comparison module should only show the diff
/// stats, false otherwise.
bool
diff_context::show_stats_only() const
{return priv_->show_stats_only_;}
 
/// Setter for the property that says if the comparison module should
/// show the soname changes in its report.
///
/// @param f the new value of the property.
void
diff_context::show_soname_change(bool f)
{priv_->show_soname_change_ = f;}
 
/// Getter for the property that says if the comparison module should
/// show the soname changes in its report.
///
/// @return the value of the property.
bool
diff_context::show_soname_change() const
{return priv_->show_soname_change_;}
 
/// Setter for the property that says if the comparison module should
/// show the architecture changes in its report.
///
/// @param f the new value of the property.
void
diff_context::show_architecture_change(bool f)
{priv_->show_architecture_change_ = f;}
 
/// Getter for the property that says if the comparison module should
/// show the architecture changes in its report.
///
/// @return the value of the property.
bool
diff_context::show_architecture_change() const
{return priv_->show_architecture_change_;}
 
/// Set a flag saying to show the deleted functions.
///
/// @param f true to show deleted functions.
void
diff_context::show_deleted_fns(bool f)
{priv_->show_deleted_fns_ = f;}
 
/// @return true if we want to show the deleted functions, false
/// otherwise.
bool
diff_context::show_deleted_fns() const
{return priv_->show_deleted_fns_;}
 
/// Set a flag saying to show the changed functions.
///
/// @param f true to show the changed functions.
void
diff_context::show_changed_fns(bool f)
{priv_->show_changed_fns_ = f;}
 
/// @return true if we want to show the changed functions, false otherwise.
bool
diff_context::show_changed_fns() const
{return priv_->show_changed_fns_;}
 
/// Set a flag saying to show the added functions.
///
/// @param f true to show the added functions.
void
diff_context::show_added_fns(bool f)
{priv_->show_added_fns_ = f;}
 
/// @return true if we want to show the added functions, false
/// otherwise.
bool
diff_context::show_added_fns() const
{return priv_->show_added_fns_;}
 
/// Set a flag saying to show the deleted variables.
///
/// @param f true to show the deleted variables.
void
diff_context::show_deleted_vars(bool f)
{priv_->show_deleted_vars_ = f;}
 
/// @return true if we want to show the deleted variables, false
/// otherwise.
bool
diff_context::show_deleted_vars() const
{return priv_->show_deleted_vars_;}
 
/// Set a flag saying to show the changed variables.
///
/// @param f true to show the changed variables.
void
diff_context::show_changed_vars(bool f)
{priv_->show_changed_vars_ = f;}
 
/// @return true if we want to show the changed variables, false otherwise.
bool
diff_context::show_changed_vars() const
{return priv_->show_changed_vars_;}
 
/// Set a flag saying to show the added variables.
///
/// @param f true to show the added variables.
void
diff_context::show_added_vars(bool f)
{priv_->show_added_vars_ = f;}
 
/// @return true if we want to show the added variables, false
/// otherwise.
bool
diff_context::show_added_vars() const
{return priv_->show_added_vars_;}
 
bool
diff_context::show_linkage_names() const
{return priv_->show_linkage_names_;}
 
void
diff_context::show_linkage_names(bool f)
{priv_->show_linkage_names_= f;}
 
/// Set a flag saying to show location information.
///
/// @param f true to show location information.
void
diff_context::show_locs(bool f)
{priv_->show_locs_= f;}
 
/// @return true if we want to show location information, false
/// otherwise.
bool
diff_context::show_locs() const
{return priv_->show_locs_;}
 
/// A getter for the flag that says if we should report about
/// functions or variables diff nodes that have *exclusively*
/// redundant diff tree children nodes.
///
/// @return the flag.
bool
diff_context::show_redundant_changes() const
{return priv_->show_redundant_changes_;}
 
/// A setter for the flag that says if we should report about
/// functions or variables diff nodes that have *exclusively*
/// redundant diff tree children nodes.
///
/// @param f the flag to set.
void
diff_context::show_redundant_changes(bool f)
{priv_->show_redundant_changes_ = f;}
 
/// Getter for the flag that indicates if symbols not referenced by
/// any debug info are to be compared and reported about.
///
/// @return the boolean flag.
bool
diff_context::show_symbols_unreferenced_by_debug_info() const
{return priv_->show_syms_unreferenced_by_di_;}
 
/// Setter for the flag that indicates if symbols not referenced by
/// any debug info are to be compared and reported about.
///
/// @param f the new flag to set.
void
diff_context::show_symbols_unreferenced_by_debug_info(bool f)
{priv_->show_syms_unreferenced_by_di_ = f;}
 
/// Getter for the flag that indicates if symbols not referenced by
/// any debug info and that got added are to be reported about.
///
/// @return true iff symbols not referenced by any debug info and that
/// got added are to be reported about.
bool
diff_context::show_added_symbols_unreferenced_by_debug_info() const
{return priv_->show_added_syms_unreferenced_by_di_;}
 
/// Setter for the flag that indicates if symbols not referenced by
/// any debug info and that got added are to be reported about.
///
/// @param f the new flag that says if symbols not referenced by any
/// debug info and that got added are to be reported about.
void
diff_context::show_added_symbols_unreferenced_by_debug_info(bool f)
{priv_->show_added_syms_unreferenced_by_di_ = f;}
 
/// Setter for the flag that indicates if changes on types unreachable
/// from global functions and variables are to be reported.
///
/// @param f if true, then changes on types unreachable from global
/// functions and variables are to be reported.
void
diff_context::show_unreachable_types(bool f)
{priv_->show_unreachable_types_ = f;}
 
/// Getter for the flag that indicates if changes on types unreachable
/// from global functions and variables are to be reported.
///
/// @return true iff changes on types unreachable from global
/// functions and variables are to be reported.
bool
diff_context::show_unreachable_types()
{return priv_->show_unreachable_types_;}
 
/// Getter of the flag that indicates if the leaf reporter should
/// display a summary of the interfaces impacted by a given leaf
/// change or not.
///
/// @return the flag that indicates if the leaf reporter should
/// display a summary of the interfaces impacted by a given leaf
/// change or not.
bool
diff_context::show_impacted_interfaces() const
{return priv_->show_impacted_interfaces_;}
 
/// Setter of the flag that indicates if the leaf reporter should
/// display a summary of the interfaces impacted by a given leaf
/// change or not.
///
/// @param f the new value of the flag that indicates if the leaf
/// reporter should display a summary of the interfaces impacted by a
/// given leaf change or not.
void
diff_context::show_impacted_interfaces(bool f)
{priv_->show_impacted_interfaces_ = f;}
 
/// Setter for the default output stream used by code of the
/// comparison engine.  By default the default output stream is a NULL
/// pointer.
///
/// @param o a pointer to the default output stream.
void
diff_context::default_output_stream(ostream* o)
{priv_->default_output_stream_ = o;}
 
/// Getter for the default output stream used by code of the
/// comparison engine.  By default the default output stream is a NULL
/// pointer.
///
/// @return a pointer to the default output stream.
ostream*
diff_context::default_output_stream()
{return priv_->default_output_stream_;}
 
/// Setter for the errror output stream used by code of the comparison
/// engine.  By default the error output stream is a NULL pointer.
///
/// @param o a pointer to the error output stream.
void
diff_context::error_output_stream(ostream* o)
{priv_->error_output_stream_ = o;}
 
/// Getter for the errror output stream used by code of the comparison
/// engine.  By default the error output stream is a NULL pointer.
///
/// @return a pointer to the error output stream.
ostream*
diff_context::error_output_stream() const
{return priv_->error_output_stream_;}
 
/// Test if the comparison engine should dump the diff tree for the
/// changed functions and variables it has.
///
/// @return true if after the comparison, the engine should dump the
/// diff tree for the changed functions and variables it has.
bool
diff_context::dump_diff_tree() const
{return priv_->dump_diff_tree_;}
 
/// Set if the comparison engine should dump the diff tree for the
/// changed functions and variables it has.
///
/// @param f true if after the comparison, the engine should dump the
/// diff tree for the changed functions and variables it has.
void
diff_context::dump_diff_tree(bool f)
{priv_->dump_diff_tree_ = f;}
 
/// Emit a textual representation of a diff tree to the error output
/// stream of the current context, for debugging purposes.
///
/// @param d the diff tree to serialize to the error output associated
/// to the current instance of @ref diff_context.
void
diff_context::do_dump_diff_tree(const diff_sptr d) const
{
  if (error_output_stream())
    print_diff_tree(d, *error_output_stream());
}
 
/// Emit a textual representation of a @ref corpus_diff tree to the error
/// output stream of the current context, for debugging purposes.
///
/// @param d the @ref corpus_diff tree to serialize to the error
/// output associated to the current instance of @ref diff_context.
void
diff_context::do_dump_diff_tree(const corpus_diff_sptr d) const
{
  if (error_output_stream())
    print_diff_tree(d, *error_output_stream());
}
// </diff_context stuff>
 
// <diff stuff>
 
/// Constructor for the @ref diff type.
///
/// This constructs a diff between two subjects that are actually
/// declarations; the first and the second one.
///
/// @param first_subject the first decl (subject) of the diff.
///
/// @param second_subject the second decl (subject) of the diff.
diff::diff(type_or_decl_base_sptr first_subject,
       type_or_decl_base_sptr second_subject)
  : priv_(new priv(first_subject, second_subject,
           diff_context_sptr(),
           NO_CHANGE_CATEGORY,
           /*reported_once=*/false,
           /*currently_reporting=*/false))
{}
 
/// Constructor for the @ref diff type.
///
/// This constructs a diff between two subjects that are actually
/// declarations; the first and the second one.
///
/// @param first_subject the first decl (subject) of the diff.
///
/// @param second_subject the second decl (subject) of the diff.
///
/// @param ctxt the context of the diff.  Note that this context
/// object must stay alive during the entire life time of the current
/// instance of @ref diff.  Otherwise, memory corruption issues occur.
diff::diff(type_or_decl_base_sptr   first_subject,
       type_or_decl_base_sptr   second_subject,
       diff_context_sptr    ctxt)
  : priv_(new priv(first_subject, second_subject,
           ctxt, NO_CHANGE_CATEGORY,
           /*reported_once=*/false,
           /*currently_reporting=*/false))
{}
 
/// Test if logging was requested
///
/// @return true iff logging was requested.
bool
diff::do_log() const
{return context()->do_log();}
 
/// Request logging (or not)
///
/// @param f true iff logging is to be requested.
void
diff::do_log(bool f)
{context()->do_log(f);}
 
/// Flag a given diff node as being traversed.
///
/// For certain diff nodes like @ref class_diff, it's important to
/// avoid traversing the node again while it's already being
/// traversed; otherwise this leads to infinite loops.  So the
/// diff::begin_traversing() and diff::end_traversing() methods flag a
/// given node as being traversed (or not), so that
/// diff::is_traversing() can tell if the node is being traversed.
///
/// Note that traversing a node means visiting it *and* visiting its
/// children nodes.
///
/// The canonical node is marked as being traversed too.
///
/// These functions are called by the traversing code.
void
diff::begin_traversing()
{
  ABG_ASSERT(!is_traversing());
  if (priv_->canonical_diff_)
    priv_->canonical_diff_->priv_->traversing_ = true;
  priv_->traversing_ = true;
}
 
/// Tell if a given node is being traversed or not.
///
/// Note that traversing a node means visiting it *and* visiting its
/// children nodes.
///
/// It's the canonical node which is looked at, actually.
///
/// Please read the comments for the diff::begin_traversing() for mode
/// context.
///
/// @return true if the current instance of @diff is being traversed.
bool
diff::is_traversing() const
{
  if (priv_->canonical_diff_)
    return priv_->canonical_diff_->priv_->traversing_;
  return priv_->traversing_;
}
 
/// Flag a given diff node as not being traversed anymore.
///
/// Note that traversing a node means visiting it *and* visiting its
/// children nodes.
///
/// Please read the comments of the function diff::begin_traversing()
/// for mode context.
void
diff::end_traversing()
{
  ABG_ASSERT(is_traversing());
  if (priv_->canonical_diff_)
    priv_->canonical_diff_->priv_->traversing_ = false;
  priv_->traversing_ = false;
}
 
/// Finish the insertion of a diff tree node into the diff graph.
///
/// This function might be called several times.  It must perform the
/// insertion only once.
///
/// For instance, certain kinds of diff tree node have specific
/// children nodes that are populated after the constructor of the
/// diff tree node has been called.  In that case, calling overloads
/// of this method ensures that these children nodes are properly
/// gathered and setup.
void
diff::finish_diff_type()
{
  if (diff::priv_->finished_)
    return;
  chain_into_hierarchy();
  diff::priv_->finished_ = true;
}
 
/// Getter of the first subject of the diff.
///
/// @return the first subject of the diff.
type_or_decl_base_sptr
diff::first_subject() const
{return dynamic_pointer_cast<type_or_decl_base>(priv_->first_subject_);}
 
/// Getter of the second subject of the diff.
///
/// @return the second subject of the diff.
type_or_decl_base_sptr
diff::second_subject() const
{return dynamic_pointer_cast<type_or_decl_base>(priv_->second_subject_);}
 
/// Getter for the children nodes of the current @ref diff node.
///
/// @return a vector of the children nodes.
const vector<diff*>&
diff::children_nodes() const
{return priv_->children_;}
 
/// Getter for the parent node of the current @ref diff node.
///
/// @return the parent node of the current @ref diff node.
const diff*
diff::parent_node() const
{return priv_->parent_;}
 
/// Getter for the canonical diff of the current instance of @ref
/// diff.
///
/// Note that the canonical diff node for the current instanc eof diff
/// node must have been set by invoking
/// class_diff::initialize_canonical_diff() on the current instance of
/// diff node.
///
/// @return the canonical diff node or null if none was set.
diff*
diff::get_canonical_diff() const
{return priv_->canonical_diff_;}
 
/// Setter for the canonical diff of the current instance of @ref
/// diff.
///
/// @param d the new canonical node to set.
void
diff::set_canonical_diff(diff * d)
{priv_->canonical_diff_ = d;}
 
/// Add a new child node to the vector of children nodes for the
/// current @ref diff node.
///
/// @param d the new child node to add to the children nodes.
void
diff::append_child_node(diff_sptr d)
{
  ABG_ASSERT(d);
 
  // Ensure 'd' is kept alive for the life time of the context of this
  // diff.
  context()->keep_diff_alive(d);
 
  // Add the underlying pointer of 'd' to the vector of children.
  // Note that this vector holds no reference to 'd'. This is to avoid
  // reference cycles.  The reference to 'd' is held by the context of
  // this diff, thanks to the call to context()->keep_diff_alive(d)
  // above.
  priv_->children_.push_back(d.get());
 
  d->priv_->parent_ = this;
}
 
/// Getter of the context of the current diff.
///
/// @return the context of the current diff.
const diff_context_sptr
diff::context() const
{return priv_->get_context();}
 
/// Setter of the context of the current diff.
///
/// @param c the new context to set.
void
diff::context(diff_context_sptr c)
{priv_->ctxt_ = c;}
 
/// Tests if we are currently in the middle of emitting a report for
/// this diff.
///
/// @return true if we are currently emitting a report for the
/// current diff, false otherwise.
bool
diff::currently_reporting() const
{
  if (priv_->canonical_diff_)
    return priv_->canonical_diff_->priv_->currently_reporting_;
  return priv_->currently_reporting_;
}
 
/// Sets a flag saying if we are currently in the middle of emitting
/// a report for this diff.
///
/// @param f true if we are currently emitting a report for the
/// current diff, false otherwise.
void
diff::currently_reporting(bool f) const
{
  if (priv_->canonical_diff_)
    priv_->canonical_diff_->priv_->currently_reporting_ = f;
  priv_->currently_reporting_ = f;
}
 
/// Tests if a report has already been emitted for the current diff.
///
/// @return true if a report has already been emitted for the
/// current diff, false otherwise.
bool
diff::reported_once() const
{
  ABG_ASSERT(priv_->canonical_diff_);
  return priv_->canonical_diff_->priv_->reported_once_;
}
 
/// The generic traversing code that walks a given diff sub-tree.
///
/// Note that there is a difference between traversing a diff node and
/// visiting it.  Basically, traversing a diff node means visiting it
/// and visiting its children nodes too.  So one can visit a node
/// without traversing it.  But traversing a node without visiting it
/// is not possible.
///
/// Note that the insertion of the "generic view" of the diff node
/// into the graph being traversed is done "on the fly".  The
/// insertion of the "typed view" of the diff node into the graph is
/// done implicitely.  To learn more about the generic and typed view
/// of the diff node, please read the introductory comments of the
/// @ref diff class.
///
/// Note that by default this traversing code visits a given class of
/// equivalence of a diff node only once.  This behaviour can been
/// changed by calling
/// diff_context::visiting_a_node_twice_is_forbidden(), but this is
/// very risky as it might create endless loops while visiting a diff
/// tree graph that has changes that refer to themselves; that is,
/// diff tree graphs with cycles.
///
/// When a diff node is encountered, the
/// diff_node_visitor::visit_begin() method is invoked on the diff
/// node first.
///
/// If the diff node has already been visited, then
/// node_visitor::visit_end() is called on it and the node traversing
/// is done; the children of the diff node are not visited in this
/// case.
///
/// If the diff node has *NOT* been visited yet, then the
/// diff_node_visitor::visit() method is invoked with it's 'pre'
/// argument set to true.  Then if the diff_node_visitor::visit()
/// returns true, then the children nodes of the diff node are
/// visited.  Otherwise, no children nodes of the diff node is
/// visited and the diff_node_visitor::visit_end() is called.
 
/// After the children nodes are visited (and only if they are
/// visited) the diff_node_visitor::visit() method is invoked with
/// it's 'pre' argument set to false.  And then the
/// diff_node_visitor::visit_end() is called.
///
/// @param v the entity that visits each node of the diff sub-tree.
///
/// @return true to tell the caller that all of the sub-tree could be
/// walked.  This instructs the caller to keep walking the rest of the
/// tree.  Return false otherwise.
bool
diff::traverse(diff_node_visitor& v)
{
  // Insert the "generic view" of the diff node into its graph.
  finish_diff_type();
 
  v.visit_begin(this);
 
  bool already_visited = false;
  if (context()->visiting_a_node_twice_is_forbidden()
      && context()->diff_has_been_visited(this))
    already_visited = true;
 
  bool mark_visited_nodes_as_traversed =
    !(v.get_visiting_kind() & DO_NOT_MARK_VISITED_NODES_AS_VISITED);
 
  if (!already_visited && !v.visit(this, /*pre=*/true))
    {
      v.visit_end(this);
      if (mark_visited_nodes_as_traversed)
    context()->mark_diff_as_visited(this);
      return false;
    }
 
  if (!(v.get_visiting_kind() & SKIP_CHILDREN_VISITING_KIND)
      && !is_traversing()
      && !already_visited)
    {
      begin_traversing();
      for (vector<diff*>::const_iterator i = children_nodes().begin();
       i != children_nodes().end();
       ++i)
    {
      if (!(*i)->traverse(v))
        {
          v.visit_end(this);
          if (mark_visited_nodes_as_traversed)
        context()->mark_diff_as_visited(this);
          end_traversing();
          return false;
        }
    }
      end_traversing();
    }
 
  if (!v.visit(this, /*pref=*/false))
    {
      v.visit_end(this);
      if (mark_visited_nodes_as_traversed)
    context()->mark_diff_as_visited(this);
      return false;
    }
 
  v.visit_end(this);
  if (!already_visited && mark_visited_nodes_as_traversed)
    context()->mark_diff_as_visited(this);
 
  return true;
}
 
/// Sets a flag saying if a report has already been emitted for the
/// current diff.
///
/// @param f true if a report has already been emitted for the
/// current diff, false otherwise.
void
diff::reported_once(bool f) const
{
  ABG_ASSERT(priv_->canonical_diff_);
  priv_->canonical_diff_->priv_->reported_once_ = f;
  priv_->reported_once_ = f;
}
 
/// Getter for the local category of the current diff tree node.
///
/// The local category represents the set of categories of a diff
/// node, not taking in account the categories inherited from its
/// children nodes.
///
/// @return the local category of the current diff tree node.
diff_category
diff::get_local_category() const
{return priv_->local_category_;}
 
/// Getter of the category of the class of equivalence of the current
/// diff tree node.
///
/// That is, if the current diff tree node has a canonical node,
/// return the category of that canonical node.  Otherwise, return the
/// category of the current node.
///
/// @return the category of the class of equivalence of the current
/// tree node.
diff_category
diff::get_class_of_equiv_category() const
{
  diff* canonical = get_canonical_diff();
  return canonical ? canonical->get_category() : get_category();
}
 
/// Getter for the category of the current diff tree node.
///
/// This category represents the union of the local category and the
/// categories inherited from the children diff nodes.
///
/// @return the category of the current diff tree node.
diff_category
diff::get_category() const
{return priv_->category_;}
 
/// Adds the current diff tree node to an additional set of
/// categories.  Note that the categories include thoses inherited
/// from the children nodes of this diff node.
///
/// @param c a bit-map representing the set of categories to add the
/// current diff tree node to.
///
/// @return the resulting bit-map representing the categories this
/// current diff tree node belongs to, including those inherited from
/// its children nodes.
diff_category
diff::add_to_category(diff_category c)
{
  priv_->category_ = priv_->category_ | c;
  return priv_->category_;
}
 
/// Adds the current diff tree node to the categories resulting from
/// the local changes of the current diff node.
///
/// @param c a bit-map representing the set of categories to add the
/// current diff tree node to.
///
/// @return the resulting bit-map representing the categories this
/// current diff tree node belongs to.
diff_category
diff::add_to_local_category(diff_category c)
{
  priv_->local_category_ = priv_->local_category_ | c;
  return priv_->local_category_;
}
 
/// Adds the current diff tree node to the categories resulting from
/// the local and inherited changes of the current diff node.
///
/// @param c a bit-map representing the set of categories to add the
/// current diff tree node to.
void
diff::add_to_local_and_inherited_categories(diff_category c)
{
  add_to_local_category(c);
  add_to_category(c);
}
 
/// Remove the current diff tree node from an a existing sef of
/// categories.  The categories include those inherited from the
/// children nodes of the current diff node.
///
/// @param c a bit-map representing the set of categories to add the
/// current diff tree node to.
///
/// @return the resulting bit-map representing the categories this
/// current diff tree onde belongs to, including the categories
/// inherited from the children nodes of the current diff node.
diff_category
diff::remove_from_category(diff_category c)
{
  priv_->category_ = priv_->category_ & ~c;
  return priv_->category_;
}
 
/// Remove the current diff tree node from the categories resulting
/// from the local changes.
///
/// @param c a bit-map representing the set of categories to add the
/// current diff tree node to.
///
/// @return the resulting bit-map representing the categories this
/// current diff tree onde belongs to.
diff_category
diff::remove_from_local_category(diff_category c)
{
  priv_->local_category_ = priv_->local_category_ & ~c;
  return priv_->local_category_;
}
 
/// Set the category of the current @ref diff node.  This category
/// includes the categories inherited from the children nodes of the
/// current diff node.
///
/// @param c the new category for the current diff node.
void
diff::set_category(diff_category c)
{priv_->category_ = c;}
 
/// Set the local category of the current @ref diff node.
///
/// @param c the new category for the current diff node.
void
diff::set_local_category(diff_category c)
{priv_->local_category_ = c;}
 
/// Test if this diff tree node is to be filtered out for reporting
/// purposes.
///
/// There is a difference between a diff node being filtered out and
/// being suppressed.  Being suppressed means that there is a
/// suppression specification that suppresses the diff node
/// specifically.  Being filtered out mean the node is either
/// suppressed, or it's filtered out because the suppression of a set
/// of (children) nodes caused this node to be filtered out as well.
/// For instance, if a function diff has all its children diff nodes
/// suppressed and if the function diff node carries no local change,
/// then the function diff node itself is going to be filtered out.
///
/// The function tests if the categories of the diff tree node are
/// "forbidden" by the context or not.
///
/// @return true iff the current diff node should NOT be reported.
bool
diff::is_filtered_out() const
{
  if (diff * canonical = get_canonical_diff())
    if ((canonical->get_category() & SUPPRESSED_CATEGORY
     || canonical->get_category() & PRIVATE_TYPE_CATEGORY)
    && !canonical->is_allowed_by_specific_negated_suppression()
    && !canonical->has_descendant_allowed_by_specific_negated_suppression()
    && !canonical->has_parent_allowed_by_specific_negated_suppression())
      // The canonical type was suppressed either by a user-provided
      // suppression specification or by a "private-type" suppression
      // specification..  This means all the classes of equivalence of
      // that canonical type were suppressed.  So this node should be
      // filtered out.
      return true;
  return priv_->is_filtered_out(get_category());
}
 
/// Test if this diff tree node is to be filtered out for reporting
/// purposes, but by considering only the categories that were *NOT*
/// inherited from its children nodes.
///
/// The function tests if the local categories of the diff tree node
/// are "forbidden" by the context or not.
///
/// @return true iff the current diff node should NOT be reported,
/// with respect to its local categories.
bool
diff::is_filtered_out_wrt_non_inherited_categories() const
{return priv_->is_filtered_out(get_local_category());}
 
/// Test if this diff tree node is to be filtered out for reporting
/// purposes, but without considering the categories that can /force/
/// the node to be unfiltered.
///
/// The function tests if the categories of the diff tree node are
/// "forbidden" by the context or not.
///
/// @return true iff the current diff node should should NOT be
/// reported, with respect to the categories that might filter it out
/// only.
bool
diff::is_filtered_out_without_looking_at_allowed_changes() const
{
  diff_category c = get_category();
  c &= ~(HAS_DESCENDANT_WITH_ALLOWED_CHANGE_CATEGORY
     | HAS_PARENT_WITH_ALLOWED_CHANGE_CATEGORY
     | HAS_ALLOWED_CHANGE_CATEGORY);
 
    return priv_->is_filtered_out(c);
}
 
/// Test if the current diff node has been suppressed by a
/// user-provided suppression specification.
///
/// @return true if the current diff node has been suppressed by a
/// user-provided suppression list.
bool
diff::is_suppressed() const
{
  bool is_private = false;
  return is_suppressed(is_private);
}
 
/// Test if the current diff node has been suppressed by a
/// user-provided suppression specification or by an auto-generated
/// "private type" suppression specification.
///
/// Note that private type suppressions are auto-generated from the
/// path to where public headers are, as given by the user.
///
/// Here is the current algorithm:
///
///         First, suppress this diff node if it's not matched by any
///         negated suppression specifications.  If it's not
///         suppressed, then suppress it if it's matched by direct
///         suppression specifications.
///
/// @param is_private_type out parameter if the current diff node was
/// suppressed because it's a private type then this parameter is set
/// to true.
///
/// @return true if the current diff node has been suppressed by a
/// user-provided suppression list.
bool
diff::is_suppressed(bool &is_private_type) const
{
  // If there is at least one negated suppression, then suppress the
  // current diff node by default ...
  bool do_suppress = !context()->negated_suppressions().empty();
 
  // ... unless there is at least one negated suppression that
  // specifically asks to keep this diff node around (un-suppressed).
  for (auto n : context()->negated_suppressions())
    if (!n->suppresses_diff(this))
      {
    do_suppress = false;
    break;
      }
 
  // Then walk the set of non-negated, AKA direct, suppressions.  If at
  // least one suppression suppresses the current diff node then the
  // diff node must be suppressed.
  for (auto d : context()->direct_suppressions())
    if (d->suppresses_diff(this))
      {
    do_suppress = true;
    if (is_private_type_suppr_spec(d))
      is_private_type = true;
    break;
      }
 
  return do_suppress;
}
 
/// Test if this diff tree node should be reported.
///
/// @return true iff the current node should be reported.
bool
diff::to_be_reported() const
{
  if (has_changes() && !is_filtered_out())
    return true;
  return false;
}
 
/// Test if this diff tree node should be reported when considering
/// the categories that were *NOT* inherited from its children nodes.
///
/// @return true iff the current node should be reported.
bool
diff::has_local_changes_to_be_reported() const
{
  if (has_local_changes()
      && !is_filtered_out_wrt_non_inherited_categories())
    return true;
  return false;
}
 
/// Test if this diff node is allowed (prevented from being
/// suppressed) by at least one negated suppression specification.
///
/// @return true if this diff node is meant to be allowed by at least
/// one negated suppression specification.
bool
diff::is_allowed_by_specific_negated_suppression() const
{
  const suppressions_type& suppressions = context()->suppressions();
  for (suppressions_type::const_iterator i = suppressions.begin();
       i != suppressions.end();
       ++i)
    {
      if (is_negated_suppression(*i)
      && !(*i)->suppresses_diff(this))
    return true;
    }
  return false;
}
 
/// Test if the current diff node has a descendant node which is
/// specifically allowed by a negated suppression specification.
///
/// @return true iff the current diff node has a descendant node
/// which is specifically allowed by a negated suppression
/// specification.
bool
diff::has_descendant_allowed_by_specific_negated_suppression() const
{
  bool result = (get_category() & HAS_DESCENDANT_WITH_ALLOWED_CHANGE_CATEGORY);
  return result;
}
 
/// Test if the current diff node has a parent node which is
/// specifically allowed by a negated suppression specification.
///
/// @return true iff the current diff node has a parent node which is
/// specifically allowed by a negated suppression specification.
bool
diff::has_parent_allowed_by_specific_negated_suppression() const
{
  bool result = (get_category() & HAS_PARENT_WITH_ALLOWED_CHANGE_CATEGORY);
  return result;
}
 
/// Get a pretty representation of the current @ref diff node.
///
/// This is suitable for e.g. emitting debugging traces for the diff
/// tree nodes.
///
/// @return the pretty representation of the diff node.
const string&
diff::get_pretty_representation() const
{
  if (priv_->pretty_representation_.empty())
    priv_->pretty_representation_ = "empty_diff";
  return priv_->pretty_representation_;
}
 
/// Default implementation of the hierachy chaining virtual function.
///
/// There are several types of diff nodes that have logical children
/// nodes; for instance, a typedef_diff has the diff of the underlying
/// type as a child node.  A var_diff has the diff of the types of the
/// variables as a child node, etc.
///
/// But because the @ref diff base has a generic representation for
/// children nodes of the all the types of @ref diff nodes (regardless
/// of the specific most-derived type of diff node) that one can get
/// using the method diff::children_nodes(), one need to populate that
/// vector of children node.
///
/// Populating that vector of children node is done by this function;
/// it must be overloaded by each most-derived type of diff node that
/// extends the @ref diff type.
void
diff::chain_into_hierarchy()
{}
 
// </diff stuff>
 
// <type_diff_base stuff>
 
type_diff_base::type_diff_base(type_base_sptr   first_subject,
                   type_base_sptr   second_subject,
                   diff_context_sptr    ctxt)
  : diff(first_subject, second_subject, ctxt),
    priv_(new priv)
{}
 
type_diff_base::~type_diff_base()
{}
// </type_diff_base stuff>
 
// <decl_diff_base stuff>
 
/// Constructor of @ref decl_diff_base.
///
/// @param first_subject the first subject of the diff.
///
/// @param second_subject the second subject of the diff.
///
/// @param ctxt the context of the diff.  This object must stay alive
/// at least during the life time of the current instance of @ref
/// decl_diff_base, otherwise, memory corruption issues occur.
decl_diff_base::decl_diff_base(decl_base_sptr   first_subject,
                   decl_base_sptr   second_subject,
                   diff_context_sptr    ctxt)
  : diff(first_subject, second_subject, ctxt),
    priv_(new priv)
{}
 
decl_diff_base::~decl_diff_base()
{}
 
// </decl_diff_base stuff>
 
// <distinct_diff stuff>
 
/// @return a pretty representation for the @ref distinct_diff node.
const string&
distinct_diff::get_pretty_representation() const
{
  if (diff::priv_->pretty_representation_.empty())
    {
      std::ostringstream o;
      o << "distinct_diff[";
      if (first_subject())
    o << first_subject()->get_pretty_representation();
      else
    o << "null";
      o << ", ";
      if (second_subject())
    o << second_subject()->get_pretty_representation() ;
      else
    o << "null";
      o << "]" ;
      diff::priv_->pretty_representation_ = o.str();
    }
  return diff::priv_->pretty_representation_;
}
 
/// Populate the vector of children node of the @ref diff base type
/// sub-object of this instance of @distinct_diff.
///
/// The children nodes can then later be retrieved using
/// diff::children_nodes().
void
distinct_diff::chain_into_hierarchy()
{
  ABG_ASSERT(entities_are_of_distinct_kinds(first(), second()));
 
  if (diff_sptr d = compatible_child_diff())
    append_child_node(d);
}
 
/// Constructor for @ref distinct_diff.
///
/// Note that the two entities considered for the diff (and passed in
/// parameter) must be of different kinds.
///
/// @param first the first entity to consider for the diff.
///
/// @param second the second entity to consider for the diff.
///
/// @param ctxt the context of the diff.  Note that this context
/// object must stay alive at least during the life time of the
/// current instance of @ref distinct_diff.  Otherwise memory
/// corruption issues occur.
distinct_diff::distinct_diff(type_or_decl_base_sptr first,
                 type_or_decl_base_sptr second,
                 diff_context_sptr ctxt)
  : diff(first, second, ctxt),
    priv_(new priv)
{ABG_ASSERT(entities_are_of_distinct_kinds(first, second));}
 
/// Getter for the first subject of the diff.
///
/// @return the first subject of the diff.
const type_or_decl_base_sptr
distinct_diff::first() const
{return first_subject();}
 
/// Getter for the second subject of the diff.
///
/// @return the second subject of the diff.
const type_or_decl_base_sptr
distinct_diff::second() const
{return second_subject();}
 
/// Getter for the child diff of this distinct_diff instance.
///
/// When a distinct_diff has two subjects that are different but
/// compatible, then the distinct_diff instance has a child diff node
/// (named the compatible child diff) that is the diff between the two
/// subjects stripped from their typedefs.  Otherwise, the compatible
/// child diff is nul.
///
/// Note that two diff subjects (that compare different) are
/// considered compatible if stripping typedefs out of them makes them
/// comparing equal.
///
/// @return the compatible child diff node, if any.  Otherwise, null.
const diff_sptr
distinct_diff::compatible_child_diff() const
{
  if (!priv_->compatible_child_diff)
    {
      type_base_sptr fs = strip_typedef(is_type(first())),
    ss = strip_typedef(is_type(second()));
 
      if (fs && ss
      && !entities_are_of_distinct_kinds(get_type_declaration(fs),
                         get_type_declaration(ss)))
    priv_->compatible_child_diff = compute_diff(get_type_declaration(fs),
                            get_type_declaration(ss),
                            context());
    }
  return priv_->compatible_child_diff;
}
 
/// Test if the two arguments are of different kind, or that are both
/// NULL.
///
/// @param first the first argument to test for similarity in kind.
///
/// @param second the second argument to test for similarity in kind.
///
/// @return true iff the two arguments are of different kind.
bool
distinct_diff::entities_are_of_distinct_kinds(type_or_decl_base_sptr first,
                          type_or_decl_base_sptr second)
{
  if (!!first != !!second)
    return true;
  if (!first && !second)
    // We do consider diffs of two empty decls as a diff of distinct
    // kinds, for now.
    return true;
  if (first == second)
    return false;
 
  const type_or_decl_base &f = *first, &s = *second;
  return typeid(f) != typeid(s);
}
 
/// @return true if the two subjects of the diff are different, false
/// otherwise.
bool
distinct_diff::has_changes() const
{return first() != second();}
 
/// @return the kind of local change carried by the current diff node.
/// The value returned is zero if the current node carries no local
/// change.
enum change_kind
distinct_diff::has_local_changes() const
{
  // Changes on a distinct_diff are all local.
  if (has_changes())
    return LOCAL_TYPE_CHANGE_KIND;
  return NO_CHANGE_KIND;
}
 
/// Emit a report about the current diff instance.
///
/// @param out the output stream to send the diff report to.
///
/// @param indent the indentation string to use in the report.
void
distinct_diff::report(ostream& out, const string& indent) const
{
  context()->get_reporter()->report(*this, out, indent);
}
 
/// Try to diff entities that are of distinct kinds.
///
/// @param first the first entity to consider for the diff.
///
/// @param second the second entity to consider for the diff.
///
/// @param ctxt the context of the diff.
///
/// @return a non-null diff if a diff object could be built, null
/// otherwise.
distinct_diff_sptr
compute_diff_for_distinct_kinds(const type_or_decl_base_sptr first,
                const type_or_decl_base_sptr second,
                diff_context_sptr ctxt)
{
  if (!distinct_diff::entities_are_of_distinct_kinds(first, second))
    return distinct_diff_sptr();
 
  distinct_diff_sptr result(new distinct_diff(first, second, ctxt));
 
  ctxt->initialize_canonical_diff(result);
 
  return result;
}
 
/// </distinct_diff stuff>
 
/// Try to compute a diff on two instances of DiffType representation.
///
/// The function template performs the diff if and only if the decl
/// representations are of a DiffType.
///
/// @tparm DiffType the type of instances to diff.
///
/// @param first the first representation of decl to consider in the
/// diff computation.
///
/// @param second the second representation of decl to consider in the
/// diff computation.
///
/// @param ctxt the diff context to use.
///
///@return the diff of the two types @p first and @p second if and
///only if they represent the parametrized type DiffType.  Otherwise,
///returns a NULL pointer value.
template<typename DiffType>
diff_sptr
try_to_diff(const type_or_decl_base_sptr first,
        const type_or_decl_base_sptr second,
        diff_context_sptr ctxt)
{
  if (shared_ptr<DiffType> f =
      dynamic_pointer_cast<DiffType>(first))
    {
      shared_ptr<DiffType> s =
    dynamic_pointer_cast<DiffType>(second);
      if (!s)
    return diff_sptr();
      return compute_diff(f, s, ctxt);
    }
  return diff_sptr();
}
 
 
/// This is a specialization of @ref try_to_diff() template to diff
/// instances of @ref class_decl.
///
/// @param first the first representation of decl to consider in the
/// diff computation.
///
/// @param second the second representation of decl to consider in the
/// diff computation.
///
/// @param ctxt the diff context to use.
template<>
diff_sptr
try_to_diff<class_decl>(const type_or_decl_base_sptr first,
            const type_or_decl_base_sptr second,
            diff_context_sptr ctxt)
{
  if (class_decl_sptr f =
      dynamic_pointer_cast<class_decl>(first))
    {
      class_decl_sptr s = dynamic_pointer_cast<class_decl>(second);
      if (!s)
    return diff_sptr();
 
      if (f->get_is_declaration_only())
    {
      class_decl_sptr f2 =
        is_class_type (f->get_definition_of_declaration());
      if (f2)
        f = f2;
    }
      if (s->get_is_declaration_only())
    {
      class_decl_sptr s2 =
        is_class_type(s->get_definition_of_declaration());
      if (s2)
        s = s2;
    }
      return compute_diff(f, s, ctxt);
    }
  return diff_sptr();
}
 
/// Try to diff entities that are of distinct kinds.
///
/// @param first the first entity to consider for the diff.
///
/// @param second the second entity to consider for the diff.
///
/// @param ctxt the context of the diff.
///
/// @return a non-null diff if a diff object could be built, null
/// otherwise.
static diff_sptr
try_to_diff_distinct_kinds(const type_or_decl_base_sptr first,
               const type_or_decl_base_sptr second,
               diff_context_sptr ctxt)
{return compute_diff_for_distinct_kinds(first, second, ctxt);}
 
/// Compute the difference between two types.
///
/// The function considers every possible types known to libabigail
/// and runs the appropriate diff function on them.
///
/// Whenever a new kind of type decl is supported by abigail, if we
/// want to be able to diff two instances of it, we need to update
/// this function to support it.
///
/// @param first the first type decl to consider for the diff
///
/// @param second the second type decl to consider for the diff.
///
/// @param ctxt the diff context to use.
///
/// @return the resulting diff.  It's a pointer to a descendent of
/// abigail::comparison::diff.
static diff_sptr
compute_diff_for_types(const type_or_decl_base_sptr& first,
               const type_or_decl_base_sptr& second,
               const diff_context_sptr& ctxt)
{
  type_or_decl_base_sptr f = first;
  type_or_decl_base_sptr s = second;
 
  diff_sptr d;
 
  ((d = try_to_diff<type_decl>(f, s, ctxt))
   ||(d = try_to_diff<enum_type_decl>(f, s, ctxt))
   ||(d = try_to_diff<union_decl>(f, s,ctxt))
   ||(d = try_to_diff<class_decl>(f, s,ctxt))
   ||(d = try_to_diff<pointer_type_def>(f, s, ctxt))
   ||(d = try_to_diff<reference_type_def>(f, s, ctxt))
   ||(d = try_to_diff<array_type_def::subrange_type>(f, s, ctxt))
   ||(d = try_to_diff<array_type_def>(f, s, ctxt))
   ||(d = try_to_diff<qualified_type_def>(f, s, ctxt))
   ||(d = try_to_diff<typedef_decl>(f, s, ctxt))
   ||(d = try_to_diff<function_type>(f, s, ctxt))
   ||(d = try_to_diff_distinct_kinds(f, s, ctxt)));
 
  ABG_ASSERT(d);
 
  return d;
}
 
diff_category
operator|(diff_category c1, diff_category c2)
{return static_cast<diff_category>(static_cast<unsigned>(c1)
                   | static_cast<unsigned>(c2));}
 
diff_category&
operator|=(diff_category& c1, diff_category c2)
{
  c1 = c1 | c2;
  return c1;
}
 
diff_category&
operator&=(diff_category& c1, diff_category c2)
{
  c1 = c1 & c2;
  return c1;
}
 
diff_category
operator^(diff_category c1, diff_category c2)
{return static_cast<diff_category>(static_cast<unsigned>(c1)
                   ^ static_cast<unsigned>(c2));}
 
diff_category
operator&(diff_category c1, diff_category c2)
{return static_cast<diff_category>(static_cast<unsigned>(c1)
                   & static_cast<unsigned>(c2));}
 
diff_category
operator~(diff_category c)
{return static_cast<diff_category>(~static_cast<unsigned>(c));}
 
 
/// Getter of a bitmap made of the set of change categories that are
/// considered harmless.
///
/// @return the bitmap made of the set of change categories that are
/// considered harmless.
diff_category
get_default_harmless_categories_bitmap()
{
  return (abigail::comparison::ACCESS_CHANGE_CATEGORY
      | abigail::comparison::COMPATIBLE_TYPE_CHANGE_CATEGORY
      | abigail::comparison::HARMLESS_DECL_NAME_CHANGE_CATEGORY
      | abigail::comparison::NON_VIRT_MEM_FUN_CHANGE_CATEGORY
      | abigail::comparison::STATIC_DATA_MEMBER_CHANGE_CATEGORY
      | abigail::comparison::HARMLESS_ENUM_CHANGE_CATEGORY
      | abigail::comparison::HARMLESS_SYMBOL_ALIAS_CHANGE_CATEGORY
      | abigail::comparison::HARMLESS_UNION_CHANGE_CATEGORY
      | abigail::comparison::HARMLESS_DATA_MEMBER_CHANGE_CATEGORY
      | abigail::comparison::TYPE_DECL_ONLY_DEF_CHANGE_CATEGORY
      | abigail::comparison::FN_PARM_TYPE_TOP_CV_CHANGE_CATEGORY
      | abigail::comparison::FN_PARM_TYPE_CV_CHANGE_CATEGORY
      | abigail::comparison::FN_RETURN_TYPE_CV_CHANGE_CATEGORY
      | abigail::comparison::VAR_TYPE_CV_CHANGE_CATEGORY
      | abigail::comparison::VOID_PTR_TO_PTR_CHANGE_CATEGORY
      | abigail::comparison::BENIGN_INFINITE_ARRAY_CHANGE_CATEGORY);
}
 
/// Getter of a bitmap made of the set of change categories that are
/// considered harmful.
///
/// @return the bitmap made of the set of change categories that are
/// considered harmful.
diff_category
get_default_harmful_categories_bitmap()
{
  return (abigail::comparison::SIZE_OR_OFFSET_CHANGE_CATEGORY
      | abigail::comparison::VIRTUAL_MEMBER_CHANGE_CATEGORY
      | abigail::comparison::FN_PARM_ADD_REMOVE_CHANGE_CATEGORY);
}
 
/// Serialize an instance of @ref diff_category to an output stream.
///
/// @param o the output stream to serialize @p c to.
///
/// @param c the instance of diff_category to serialize.
///
/// @return the output stream to serialize @p c to.
ostream&
operator<<(ostream& o, diff_category c)
{
  bool emitted_a_category = false;
 
  if (c == NO_CHANGE_CATEGORY)
    {
      o << "NO_CHANGE_CATEGORY";
      emitted_a_category = true;
    }
 
  if (c & ACCESS_CHANGE_CATEGORY)
    {
      if (emitted_a_category)
    o << "|";
      o << "ACCESS_CHANGE_CATEGORY";
      emitted_a_category |= true;
    }
 
  if (c & COMPATIBLE_TYPE_CHANGE_CATEGORY)
    {
      if (emitted_a_category)
    o << "|";
      o << "COMPATIBLE_TYPE_CHANGE_CATEGORY";
      emitted_a_category |= true;
    }
 
  if (c & HARMLESS_DECL_NAME_CHANGE_CATEGORY)
    {
      if (emitted_a_category)
    o << "|";
      o << "HARMLESS_DECL_NAME_CHANGE_CATEGORY";
      emitted_a_category |= true;
    }
 
  if (c & NON_VIRT_MEM_FUN_CHANGE_CATEGORY)
    {
      if (emitted_a_category)
    o << "|";
      o << "NON_VIRT_MEM_FUN_CHANGE_CATEGORY";
      emitted_a_category |= true;
    }
 
  if (c & STATIC_DATA_MEMBER_CHANGE_CATEGORY)
    {
      if (emitted_a_category)
    o << "|";
      o << "STATIC_DATA_MEMBER_CHANGE_CATEGORY";
      emitted_a_category |= true;
    }
 
  if (c & HARMLESS_ENUM_CHANGE_CATEGORY)
    {
      if (emitted_a_category)
    o << "|";
      o << "HARMLESS_ENUM_CHANGE_CATEGORY";
      emitted_a_category |= true;
    }
 
    if (c & HARMLESS_DATA_MEMBER_CHANGE_CATEGORY)
    {
      if (emitted_a_category)
    o << "|";
      o << "HARMLESS_DATA_MEMBER_CHANGE_CATEGORY";
      emitted_a_category |= true;
    }
 
  if (c & HARMLESS_SYMBOL_ALIAS_CHANGE_CATEGORY)
    {
      if (emitted_a_category)
    o << "|";
      o << "HARMLESS_SYMBOL_ALIAS_CHANGE_CATEGORY";
      emitted_a_category |= true;
    }
 
  if (c & HARMLESS_UNION_CHANGE_CATEGORY)
    {
      if (emitted_a_category)
    o << "|";
      o << "HARMLESS_UNION_CHANGE_CATEGORY";
      emitted_a_category |= true;
    }
 
  if (c & SUPPRESSED_CATEGORY)
    {
      if (emitted_a_category)
    o << "|";
      o << "SUPPRESSED_CATEGORY";
      emitted_a_category |= true;
    }
 
  if (c & PRIVATE_TYPE_CATEGORY)
    {
      if (emitted_a_category)
    o << "|";
      o << "PRIVATE_TYPE_CATEGORY";
      emitted_a_category |= true;
    }
 
  if (c & SIZE_OR_OFFSET_CHANGE_CATEGORY)
    {
      if (emitted_a_category)
    o << "|";
      o << "SIZE_OR_OFFSET_CHANGE_CATEGORY";
      emitted_a_category |= true;
    }
 
  if (c & VIRTUAL_MEMBER_CHANGE_CATEGORY)
    {
      if (emitted_a_category)
    o << "|";
      o << "VIRTUAL_MEMBER_CHANGE_CATEGORY";
      emitted_a_category |= true;
    }
 
  if (c & REDUNDANT_CATEGORY)
    {
      if (emitted_a_category)
    o << "|";
      o << "REDUNDANT_CATEGORY";
      emitted_a_category |= true;
    }
 
  if (c & TYPE_DECL_ONLY_DEF_CHANGE_CATEGORY)
    {
      if (emitted_a_category)
    o << "|";
      o << "TYPE_DECL_ONLY_DEF_CHANGE_CATEGORY";
      emitted_a_category |= true;
    }
 
  if (c & FN_PARM_TYPE_TOP_CV_CHANGE_CATEGORY)
    {
      if (emitted_a_category)
    o << "|";
      o << "FN_PARM_TYPE_TOP_CV_CHANGE_CATEGORY";
      emitted_a_category |= true;
    }
 
  if (c & FN_PARM_TYPE_CV_CHANGE_CATEGORY)
    {
      if (emitted_a_category)
    o << "|";
      o << "FN_PARM_TYPE_CV_CHANGE_CATEGORY";
      emitted_a_category |= true;
    }
 
  if (c & FN_RETURN_TYPE_CV_CHANGE_CATEGORY)
    {
      if (emitted_a_category)
    o << "|";
      o << "FN_RETURN_TYPE_CV_CHANGE_CATEGORY";
      emitted_a_category |= true;
    }
 
    if (c & FN_PARM_ADD_REMOVE_CHANGE_CATEGORY)
    {
      if (emitted_a_category)
    o << "|";
      o << "FN_PARM_ADD_REMOVE_CHANGE_CATEGORY";
      emitted_a_category |= true;
    }
 
  if (c & VAR_TYPE_CV_CHANGE_CATEGORY)
    {
      if (emitted_a_category)
    o << "|";
      o << "VAR_TYPE_CV_CHANGE_CATEGORY";
      emitted_a_category |= true;
    }
 
  if (c & VOID_PTR_TO_PTR_CHANGE_CATEGORY)
    {
      if (emitted_a_category)
    o << "|";
      o << "VOID_PTR_TO_PTR_CHANGE_CATEGORY";
      emitted_a_category |= true;
    }
 
  if (c & BENIGN_INFINITE_ARRAY_CHANGE_CATEGORY)
    {
      if (emitted_a_category)
    o << "|";
      o << "BENIGN_INFINITE_ARRAY_CHANGE_CATEGORY";
      emitted_a_category |= true;
    }
 
  if (c & HAS_ALLOWED_CHANGE_CATEGORY)
    {
      if (emitted_a_category)
    o << "|";
      o << "HAS_ALLOWED_CHANGE_CATEGORY";
      emitted_a_category |= true;
    }
 
  if (c & HAS_DESCENDANT_WITH_ALLOWED_CHANGE_CATEGORY)
    {
      if (emitted_a_category)
    o << "|";
      o << "HAS_DESCENDANT_WITH_ALLOWED_CHANGE_CATEGORY";
      emitted_a_category |= true;
    }
 
    if (c & HAS_PARENT_WITH_ALLOWED_CHANGE_CATEGORY)
    {
      if (emitted_a_category)
    o << "|";
      o << "HAS_PARENT_WITH_ALLOWED_CHANGE_CATEGORY";
      emitted_a_category |= true;
    }
 
  return o;
}
 
/// Compute the difference between two decls.
///
/// The function consider every possible decls known to libabigail and
/// runs the appropriate diff function on them.
///
/// Whenever a new kind of non-type decl is supported by abigail, if
/// we want to be able to diff two instances of it, we need to update
/// this function to support it.
///
/// @param first the first decl to consider for the diff
///
/// @param second the second decl to consider for the diff.
///
/// @param ctxt the diff context to use.
///
/// @return the resulting diff.
static diff_sptr
compute_diff_for_decls(const decl_base_sptr first,
               const decl_base_sptr second,
               diff_context_sptr ctxt)
{
 
  diff_sptr d;
 
  ((d = try_to_diff<function_decl>(first, second, ctxt))
   || (d = try_to_diff<var_decl>(first, second, ctxt))
   || (d = try_to_diff_distinct_kinds(first, second, ctxt)));
 
   ABG_ASSERT(d);
 
  return d;
}
 
/// Compute the difference between two decls.  The decls can represent
/// either type declarations, or non-type declaration.
///
/// Note that the two decls must have been created in the same @ref
/// environment, otherwise, this function aborts.
///
/// @param first the first decl to consider.
///
/// @param second the second decl to consider.
///
/// @param ctxt the diff context to use.
///
/// @return the resulting diff, or NULL if the diff could not be
/// computed.
diff_sptr
compute_diff(const decl_base_sptr   first,
         const decl_base_sptr   second,
         diff_context_sptr      ctxt)
{
  if (!first || !second)
    return diff_sptr();
 
  diff_sptr d;
  if (is_type(first) && is_type(second))
    d = compute_diff_for_types(first, second, ctxt);
  else
    d = compute_diff_for_decls(first, second, ctxt);
  ABG_ASSERT(d);
  return d;
}
 
/// Compute the difference between two types.
///
/// Note that the two types must have been created in the same @ref
/// environment, otherwise, this function aborts.
///
/// @param first the first type to consider.
///
/// @param second the second type to consider.
///
/// @param ctxt the diff context to use.
///
/// @return the resulting diff, or NULL if the diff couldn't be
/// computed.
diff_sptr
compute_diff(const type_base_sptr   first,
         const type_base_sptr   second,
         diff_context_sptr      ctxt)
{
  decl_base_sptr f = get_type_declaration(first),
    s = get_type_declaration(second);
 
  diff_sptr d = compute_diff_for_types(f,s, ctxt);
  ABG_ASSERT(d);
  return d;
}
 
/// Get a copy of the pretty representation of a diff node.
///
/// @param d the diff node to consider.
///
/// @return the pretty representation string.
string
get_pretty_representation(diff* d)
{
  if (!d)
    return "";
  string prefix= "diff of ";
  return prefix + get_pretty_representation(d->first_subject());
}
 
// <var_diff stuff>
 
/// Populate the vector of children node of the @ref diff base type
/// sub-object of this instance of @ref var_diff.
///
/// The children node can then later be retrieved using
/// diff::children_node().
void
var_diff::chain_into_hierarchy()
{append_child_node(type_diff());}
 
/// @return the pretty representation for this current instance of
/// @ref var_diff.
const string&
var_diff::get_pretty_representation() const
{
  if (diff::priv_->pretty_representation_.empty())
    {
      std::ostringstream o;
      o << "var_diff["
    << first_subject()->get_pretty_representation()
    << ", "
    << second_subject()->get_pretty_representation()
    << "]";
      diff::priv_->pretty_representation_ = o.str();
    }
  return diff::priv_->pretty_representation_;
}
/// Constructor for @ref var_diff.
///
/// @param first the first instance of @ref var_decl to consider in
/// the diff.
///
/// @param second the second instance of @ref var_decl to consider in
/// the diff.
///
/// @param type_diff the diff between types of the instances of
/// var_decl.
///
/// @param ctxt the diff context to use.
var_diff::var_diff(var_decl_sptr    first,
           var_decl_sptr    second,
           diff_sptr        type_diff,
           diff_context_sptr    ctxt)
  : decl_diff_base(first, second, ctxt),
    priv_(new priv)
{priv_->type_diff_ = type_diff;}
 
/// Getter for the first @ref var_decl of the diff.
///
/// @return the first @ref var_decl of the diff.
var_decl_sptr
var_diff::first_var() const
{return dynamic_pointer_cast<var_decl>(first_subject());}
 
/// Getter for the second @ref var_decl of the diff.
///
/// @return the second @ref var_decl of the diff.
var_decl_sptr
var_diff::second_var() const
{return dynamic_pointer_cast<var_decl>(second_subject());}
 
/// Getter for the diff of the types of the instances of @ref
/// var_decl.
///
/// @return the diff of the types of the instances of @ref var_decl.
diff_sptr
var_diff::type_diff() const
{
  if (diff_sptr result = priv_->type_diff_.lock())
    return result;
  else
    {
      result = compute_diff(first_var()->get_type(),
                second_var()->get_type(),
                context());
      context()->keep_diff_alive(result);
      priv_->type_diff_ = result;
      return result;
    }
}
 
/// Return true iff the diff node has a change.
///
/// @return true iff the diff node has a change.
bool
var_diff::has_changes() const
{return *first_var() != *second_var();}
 
/// @return the kind of local change carried by the current diff node.
/// The value returned is zero if the current node carries no local
/// change.
enum change_kind
var_diff::has_local_changes() const
{
  ir::change_kind k = ir::NO_CHANGE_KIND;
  if (!equals(*first_var(), *second_var(), &k))
    return k & ir::ALL_LOCAL_CHANGES_MASK;
  return ir::NO_CHANGE_KIND;
}
 
/// Report the diff in a serialized form.
///
/// @param out the stream to serialize the diff to.
///
/// @param indent the prefix to use for the indentation of this
/// serialization.
void
var_diff::report(ostream& out, const string& indent) const
{
  context()->get_reporter()->report(*this, out, indent);
}
 
/// Compute the diff between two instances of @ref var_decl.
///
/// Note that the two decls must have been created in the same @ref
/// environment, otherwise, this function aborts.
///
/// @param first the first @ref var_decl to consider for the diff.
///
/// @param second the second @ref var_decl to consider for the diff.
///
/// @param ctxt the diff context to use.
///
/// @return the resulting diff between the two @ref var_decl.
var_diff_sptr
compute_diff(const var_decl_sptr    first,
         const var_decl_sptr    second,
         diff_context_sptr      ctxt)
{
  var_diff_sptr d(new var_diff(first, second, diff_sptr(), ctxt));
  ctxt->initialize_canonical_diff(d);
 
  return d;
}
 
// </var_diff stuff>
 
// <pointer_type_def stuff>
 
/// Populate the vector of children node of the @ref diff base type
/// sub-object of this instance of @ref pointer_diff.
///
/// The children node can then later be retrieved using
/// diff::children_node().
void
pointer_diff::chain_into_hierarchy()
{append_child_node(underlying_type_diff());}
 
/// Constructor for a pointer_diff.
///
/// @param first the first pointer to consider for the diff.
///
/// @param second the secon pointer to consider for the diff.
///
/// @param ctxt the diff context to use.
pointer_diff::pointer_diff(pointer_type_def_sptr    first,
               pointer_type_def_sptr    second,
               diff_sptr            underlying,
               diff_context_sptr        ctxt)
  : type_diff_base(first, second, ctxt),
    priv_(new priv(underlying))
{}
 
/// Getter for the first subject of a pointer diff
///
/// @return the first pointer considered in this pointer diff.
const pointer_type_def_sptr
pointer_diff::first_pointer() const
{return dynamic_pointer_cast<pointer_type_def>(first_subject());}
 
/// Getter for the second subject of a pointer diff
///
/// @return the second pointer considered in this pointer diff.
const pointer_type_def_sptr
pointer_diff::second_pointer() const
{return dynamic_pointer_cast<pointer_type_def>(second_subject());}
 
/// @return the pretty represenation for the current instance of @ref
/// pointer_diff.
const string&
pointer_diff::get_pretty_representation() const
{
  if (diff::priv_->pretty_representation_.empty())
    {
      std::ostringstream o;
      o << "pointer_diff["
    << first_subject()->get_pretty_representation()
    << ", "
    << second_subject()->get_pretty_representation()
    << "]";
      diff::priv_->pretty_representation_ = o.str();
    }
  return diff::priv_->pretty_representation_;
}
 
/// Return true iff the current diff node carries a change.
///
/// @return true iff the current diff node carries a change.
bool
pointer_diff::has_changes() const
{return first_pointer() != second_pointer();}
 
/// @return the kind of local change carried by the current diff node.
/// The value returned is zero if the current node carries no local
/// change.
enum change_kind
pointer_diff::has_local_changes() const
{
  ir::change_kind k = ir::NO_CHANGE_KIND;
  if (!equals(*first_pointer(), *second_pointer(), &k))
    return k & ir::ALL_LOCAL_CHANGES_MASK;
  return ir::NO_CHANGE_KIND;
}
 
/// Getter for the diff between the pointed-to types of the pointers
/// of this diff.
///
/// @return the diff between the pointed-to types.
diff_sptr
pointer_diff::underlying_type_diff() const
{return priv_->underlying_type_diff_;}
 
/// Setter for the diff between the pointed-to types of the pointers
/// of this diff.
///
/// @param d the new diff between the pointed-to types of the pointers
/// of this diff.
void
pointer_diff::underlying_type_diff(const diff_sptr d)
{priv_->underlying_type_diff_ = d;}
 
/// Report the diff in a serialized form.
///
/// @param out the stream to serialize the diff to.
///
/// @param indent the prefix to use for the indentation of this
/// serialization.
void
pointer_diff::report(ostream& out, const string& indent) const
{
  context()->get_reporter()->report(*this, out, indent);
}
 
/// Compute the diff between between two pointers.
///
/// Note that the two types must have been created in the same @ref
/// environment, otherwise, this function aborts.
///
/// @param first the pointer to consider for the diff.
///
/// @param second the pointer to consider for the diff.
///
/// @return the resulting diff between the two pointers.
///
/// @param ctxt the diff context to use.
pointer_diff_sptr
compute_diff(pointer_type_def_sptr  first,
         pointer_type_def_sptr  second,
         diff_context_sptr      ctxt)
{
  diff_sptr d = compute_diff_for_types(first->get_pointed_to_type(),
                       second->get_pointed_to_type(),
                       ctxt);
  pointer_diff_sptr result(new pointer_diff(first, second, d, ctxt));
  ctxt->initialize_canonical_diff(result);
 
  return result;
}
 
// </pointer_type_def>
 
// <subrange_diff >
 
/// Constructor of the @ref subrange_diff diff node type.
///
/// @param first the first subrange type to consider for the diff.
///
/// @param second the second subrange type to consider for the diff.
///
/// @param underlying_type_diff the underlying type diff between @p
/// first and @p second.
///
/// @param ctxt the diff context to use.
subrange_diff::subrange_diff
(const array_type_def::subrange_sptr&   first,
 const array_type_def::subrange_sptr&   second,
 const diff_sptr&           underlying_type_diff,
 const diff_context_sptr        ctxt)
  : type_diff_base(first, second, ctxt),
    priv_(new priv(underlying_type_diff))
{}
 
 
/// Getter of the first subrange of the current instance @ref
/// subrange_diff.
///
/// @return The first subrange of the current instance @ref subrange_diff.
const array_type_def::subrange_sptr
subrange_diff::first_subrange() const
{return is_subrange_type(first_subject());}
 
/// Getter of the second subrange of the current instance @ref
/// subrange_diff.
///
/// @return The second subrange of the current instance @ref
/// subrange_diff.
const array_type_def::subrange_sptr
subrange_diff::second_subrange() const
{return is_subrange_type(second_subject());}
 
/// Getter of the diff node of the underlying types of the current
/// @ref subrange_diff diff node.
///
/// @return The diff node of the underlying types of the current @ref
/// subrange_diff diff node.
const diff_sptr
subrange_diff::underlying_type_diff() const
{return priv_->underlying_type_diff_;}
 
/// Getter the pretty representation of the @ref subrange_diff diff
/// node.
///
/// @return The pretty representation of the @ref subrange_diff diff node.
const string&
subrange_diff::get_pretty_representation() const
{
    if (diff::priv_->pretty_representation_.empty())
    {
      std::ostringstream o;
      o << "subrange_diff["
    << first_subject()->get_pretty_representation()
    << ","
    << second_subject()->get_pretty_representation()
    << "]";
      diff::priv_->pretty_representation_ = o.str();
    }
    return diff::priv_->pretty_representation_;
}
 
/// Test if the current @ref subrange_diff node carries any change.
///
/// @return true iff the current @ref subrange_diff node carries any
/// change.
bool
subrange_diff::has_changes() const
{return *first_subrange() != *second_subrange();}
 
/// Test if the current @ref subrange_diff node carries any local
/// change.
///
/// @return true iff the current @ref subrange_diff node carries any
/// local change.
enum change_kind
subrange_diff::has_local_changes() const
{
  ir::change_kind k = ir::NO_CHANGE_KIND;
  if (!equals(*first_subrange(), *second_subrange(), &k))
    return k & ir::ALL_LOCAL_CHANGES_MASK;
  return ir::NO_CHANGE_KIND;
}
 
/// Report about the changes carried by this node.
///
/// @param out the output stream to send the report to.
///
/// @param indent the indentation string to use.
void
subrange_diff::report(ostream& out, const string& indent) const
{context()->get_reporter()->report(*this, out, indent);}
 
/// Populate the vector of children node of the @ref diff base type
/// sub-object of this instance of @ref subrange_diff.
///
/// The children node can then later be retrieved using
/// diff::children_node().
void
subrange_diff::chain_into_hierarchy()
{append_child_node(underlying_type_diff());}
 
/// Compute the diff between two instances of @ref subrange_diff.
///
/// Note that the two decls must have been created in the same @ref
/// environment, otherwise, this function aborts.
///
/// @param first the first @ref subrange_diff to consider for the diff.
///
/// @param second the second @ref subrange_diff to consider for the diff.
///
/// @param ctxt the diff context to use.
///
/// @return the resulting diff between the two @ref subrange_diff.
subrange_diff_sptr
compute_diff(array_type_def::subrange_sptr first,
         array_type_def::subrange_sptr second,
         diff_context_sptr ctxt)
{
  diff_sptr d = compute_diff_for_types(first->get_underlying_type(),
                       second->get_underlying_type(),
                       ctxt);
 
  subrange_diff_sptr result(new subrange_diff(first, second, d, ctxt));
  ctxt->initialize_canonical_diff(result);
  return result;
}
 
//</subrange_diff >
 
 
// <array_type_def>
 
/// Populate the vector of children node of the @ref diff base type
/// sub-object of this instance of @ref array_diff.
///
/// The children node can then later be retrieved using
/// diff::children_node().
void
array_diff::chain_into_hierarchy()
{append_child_node(element_type_diff());}
 
/// Constructor for array_diff
///
/// @param first the first array_type of the diff.
///
/// @param second the second array_type of the diff.
///
/// @param element_type_diff the diff between the two array element
/// types.
///
/// @param ctxt the diff context to use.
array_diff::array_diff(const array_type_def_sptr    first,
               const array_type_def_sptr    second,
               diff_sptr            element_type_diff,
               diff_context_sptr        ctxt)
  : type_diff_base(first, second, ctxt),
    priv_(new priv(element_type_diff))
{}
 
/// Getter for the first array of the diff.
///
/// @return the first array of the diff.
const array_type_def_sptr
array_diff::first_array() const
{return dynamic_pointer_cast<array_type_def>(first_subject());}
 
/// Getter for the second array of the diff.
///
/// @return for the second array of the diff.
const array_type_def_sptr
array_diff::second_array() const
{return dynamic_pointer_cast<array_type_def>(second_subject());}
 
/// Getter for the diff between the two types of array elements.
///
/// @return the diff between the two types of array elements.
const diff_sptr&
array_diff::element_type_diff() const
{return priv_->element_type_diff_;}
 
/// Setter for the diff between the two array element types.
///
/// @param d the new diff betweend the two array element types.
void
array_diff::element_type_diff(diff_sptr d)
{priv_->element_type_diff_ = d;}
 
/// @return the pretty representation for the current instance of @ref
/// array_diff.
const string&
array_diff::get_pretty_representation() const
{
  if (diff::priv_->pretty_representation_.empty())
    {
      std::ostringstream o;
      o << "array_diff["
    << first_subject()->get_pretty_representation()
    << ", "
    << second_subject()->get_pretty_representation()
    << "]";
      diff::priv_->pretty_representation_ = o.str();
    }
  return diff::priv_->pretty_representation_;
}
 
/// Return true iff the current diff node carries a change.
///
/// @return true iff the current diff node carries a change.
bool
array_diff::has_changes() const
{
  bool l = false;
 
  //  the array element types match check for differing dimensions
  //  etc...
  array_type_def_sptr
    f = dynamic_pointer_cast<array_type_def>(first_subject()),
    s = dynamic_pointer_cast<array_type_def>(second_subject());
 
  if (f->get_name() != s->get_name())
    l |= true;
  if (f->get_size_in_bits() != s->get_size_in_bits())
    l |= true;
  if (f->get_alignment_in_bits() != s->get_alignment_in_bits())
    l |= true;
 
  l |=  element_type_diff()
    ? element_type_diff()->has_changes()
    : false;
 
  return l;
}
 
 
/// @return the kind of local change carried by the current diff node.
/// The value returned is zero if the current node carries no local
/// change.
enum change_kind
array_diff::has_local_changes() const
{
  ir::change_kind k = ir::NO_CHANGE_KIND;
  if (!equals(*first_array(), *second_array(), &k))
    return k & ir::ALL_LOCAL_CHANGES_MASK;
  return ir::NO_CHANGE_KIND;
}
 
/// Report the diff in a serialized form.
///
/// @param out the output stream to serialize the dif to.
///
/// @param indent the string to use for indenting the report.
void
array_diff::report(ostream& out, const string& indent) const
{
  context()->get_reporter()->report(*this, out, indent);
}
 
/// Compute the diff between two arrays.
///
/// Note that the two types must have been created in the same @ref
/// environment, otherwise, this function aborts.
///
/// @param first the first array to consider for the diff.
///
/// @param second the second array to consider for the diff.
///
/// @param ctxt the diff context to use.
array_diff_sptr
compute_diff(array_type_def_sptr    first,
         array_type_def_sptr    second,
         diff_context_sptr      ctxt)
{
  diff_sptr d = compute_diff_for_types(first->get_element_type(),
                       second->get_element_type(),
                       ctxt);
  array_diff_sptr result(new array_diff(first, second, d, ctxt));
  ctxt->initialize_canonical_diff(result);
  return result;
}
// </array_type_def>
 
// <reference_type_def>
 
/// Populate the vector of children node of the @ref diff base type
/// sub-object of this instance of @ref reference_diff.
///
/// The children node can then later be retrieved using
/// diff::children_node().
void
reference_diff::chain_into_hierarchy()
{append_child_node(underlying_type_diff());}
 
/// Constructor for reference_diff
///
/// @param first the first reference_type of the diff.
///
/// @param second the second reference_type of the diff.
///
/// @param ctxt the diff context to use.
reference_diff::reference_diff(const reference_type_def_sptr    first,
                   const reference_type_def_sptr    second,
                   diff_sptr            underlying,
                   diff_context_sptr        ctxt)
  : type_diff_base(first, second, ctxt),
    priv_(new priv(underlying))
{}
 
/// Getter for the first reference of the diff.
///
/// @return the first reference of the diff.
reference_type_def_sptr
reference_diff::first_reference() const
{return dynamic_pointer_cast<reference_type_def>(first_subject());}
 
/// Getter for the second reference of the diff.
///
/// @return for the second reference of the diff.
reference_type_def_sptr
reference_diff::second_reference() const
{return dynamic_pointer_cast<reference_type_def>(second_subject());}
 
 
/// Getter for the diff between the two referred-to types.
///
/// @return the diff between the two referred-to types.
const diff_sptr&
reference_diff::underlying_type_diff() const
{return priv_->underlying_type_diff_;}
 
/// Setter for the diff between the two referred-to types.
///
/// @param d the new diff betweend the two referred-to types.
diff_sptr&
reference_diff::underlying_type_diff(diff_sptr d)
{
  priv_->underlying_type_diff_ = d;
  return priv_->underlying_type_diff_;
}
 
/// @return the pretty representation for the current instance of @ref
/// reference_diff.
const string&
reference_diff::get_pretty_representation() const
{
  if (diff::priv_->pretty_representation_.empty())
    {
      std::ostringstream o;
      o << "reference_diff["
    << first_subject()->get_pretty_representation()
    << ", "
    << second_subject()->get_pretty_representation()
    << "]";
      diff::priv_->pretty_representation_ = o.str();
    }
  return diff::priv_->pretty_representation_;
}
 
/// Return true iff the current diff node carries a change.
///
/// @return true iff the current diff node carries a change.
bool
reference_diff::has_changes() const
{
  return first_reference() != second_reference();
}
 
/// @return the kind of local change carried by the current diff node.
/// The value returned is zero if the current node carries no local
/// change.
enum change_kind
reference_diff::has_local_changes() const
{
  ir::change_kind k = ir::NO_CHANGE_KIND;
  if (!equals(*first_reference(), *second_reference(), &k))
    return k & ir::ALL_LOCAL_CHANGES_MASK;
  return ir::NO_CHANGE_KIND;
}
 
/// Report the diff in a serialized form.
///
/// @param out the output stream to serialize the dif to.
///
/// @param indent the string to use for indenting the report.
void
reference_diff::report(ostream& out, const string& indent) const
{
  context()->get_reporter()->report(*this, out, indent);
}
 
/// Compute the diff between two references.
///
/// Note that the two types must have been created in the same @ref
/// environment, otherwise, this function aborts.
///
/// @param first the first reference to consider for the diff.
///
/// @param second the second reference to consider for the diff.
///
/// @param ctxt the diff context to use.
reference_diff_sptr
compute_diff(reference_type_def_sptr    first,
         reference_type_def_sptr    second,
         diff_context_sptr      ctxt)
{
  diff_sptr d = compute_diff_for_types(first->get_pointed_to_type(),
                       second->get_pointed_to_type(),
                       ctxt);
  reference_diff_sptr result(new reference_diff(first, second, d, ctxt));
  ctxt->initialize_canonical_diff(result);
  return result;
}
// </reference_type_def>
 
// <qualified_type_diff stuff>
 
/// Populate the vector of children node of the @ref diff base type
/// sub-object of this instance of @ref qualified_type_diff.
///
/// The children node can then later be retrieved using
/// diff::children_node().
void
qualified_type_diff::chain_into_hierarchy()
{append_child_node(leaf_underlying_type_diff());}
 
/// Constructor for qualified_type_diff.
///
/// @param first the first qualified type of the diff.
///
/// @param second the second qualified type of the diff.
///
/// @param ctxt the diff context to use.
qualified_type_diff::qualified_type_diff(qualified_type_def_sptr    first,
                     qualified_type_def_sptr    second,
                     diff_sptr          under,
                     diff_context_sptr      ctxt)
  : type_diff_base(first, second, ctxt),
    priv_(new priv(under))
{}
 
/// Getter for the first qualified type of the diff.
///
/// @return the first qualified type of the diff.
const qualified_type_def_sptr
qualified_type_diff::first_qualified_type() const
{return dynamic_pointer_cast<qualified_type_def>(first_subject());}
 
/// Getter for the second qualified type of the diff.
///
/// @return the second qualified type of the diff.
const qualified_type_def_sptr
qualified_type_diff::second_qualified_type() const
{return dynamic_pointer_cast<qualified_type_def>(second_subject());}
 
/// Getter for the diff between the underlying types of the two
/// qualified types.
///
/// @return the diff between the underlying types of the two qualified
/// types.
diff_sptr
qualified_type_diff::underlying_type_diff() const
{return priv_->underlying_type_diff;}
 
/// Getter for the diff between the most underlying non-qualified
/// types of two qualified types.
///
/// @return the diff between the most underlying non-qualified types
/// of two qualified types.
diff_sptr
qualified_type_diff::leaf_underlying_type_diff() const
{
  if (!priv_->leaf_underlying_type_diff)
    priv_->leaf_underlying_type_diff
      = compute_diff_for_types(get_leaf_type(first_qualified_type()),
                   get_leaf_type(second_qualified_type()),
                   context());
 
  return priv_->leaf_underlying_type_diff;
}
 
/// Setter for the diff between the underlying types of the two
/// qualified types.
///
/// @return the diff between the underlying types of the two qualified
/// types.
void
qualified_type_diff::underlying_type_diff(const diff_sptr d)
{priv_->underlying_type_diff = d;}
 
/// @return the pretty representation of the current instance of @ref
/// qualified_type_diff.
const string&
qualified_type_diff::get_pretty_representation() const
{
  if (diff::priv_->pretty_representation_.empty())
    {
      std::ostringstream o;
      o << "qualified_type_diff["
    << first_subject()->get_pretty_representation()
    << ", "
    << second_subject()->get_pretty_representation()
    << "]";
      diff::priv_->pretty_representation_ = o.str();
    }
  return diff::priv_->pretty_representation_;
}
 
/// Return true iff the current diff node carries a change.
///
/// @return true iff the current diff node carries a change.
bool
qualified_type_diff::has_changes() const
{return first_qualified_type() != second_qualified_type();}
 
/// @return the kind of local change carried by the current diff node.
/// The value returned is zero if the current node carries no local
/// change.
enum change_kind
qualified_type_diff::has_local_changes() const
{
  ir::change_kind k = ir::NO_CHANGE_KIND;
  if (!equals(*first_qualified_type(), *second_qualified_type(), &k))
    return k & ir::ALL_LOCAL_CHANGES_MASK;
  return ir::NO_CHANGE_KIND;
}
 
/// Report the diff in a serialized form.
///
/// @param out the output stream to serialize to.
///
/// @param indent the string to use to indent the lines of the report.
void
qualified_type_diff::report(ostream& out, const string& indent) const
{
  context()->get_reporter()->report(*this, out, indent);
}
 
/// Compute the diff between two qualified types.
///
/// Note that the two types must have been created in the same @ref
/// environment, otherwise, this function aborts.
///
/// @param first the first qualified type to consider for the diff.
///
/// @param second the second qualified type to consider for the diff.
///
/// @param ctxt the diff context to use.
qualified_type_diff_sptr
compute_diff(const qualified_type_def_sptr  first,
         const qualified_type_def_sptr  second,
         diff_context_sptr          ctxt)
{
  diff_sptr d = compute_diff_for_types(first->get_underlying_type(),
                       second->get_underlying_type(),
                       ctxt);
  qualified_type_diff_sptr result(new qualified_type_diff(first, second,
                              d, ctxt));
  ctxt->initialize_canonical_diff(result);
  return result;
}
 
// </qualified_type_diff stuff>
 
// <enum_diff stuff>
 
/// Clear the lookup tables useful for reporting an enum_diff.
///
/// This function must be updated each time a lookup table is added or
/// removed from the class_diff::priv.
void
enum_diff::clear_lookup_tables()
{
  priv_->deleted_enumerators_.clear();
  priv_->inserted_enumerators_.clear();
  priv_->changed_enumerators_.clear();
}
 
/// Tests if the lookup tables are empty.
///
/// @return true if the lookup tables are empty, false otherwise.
bool
enum_diff::lookup_tables_empty() const
{
  return (priv_->deleted_enumerators_.empty()
      && priv_->inserted_enumerators_.empty()
      && priv_->changed_enumerators_.empty());
}
 
/// If the lookup tables are not yet built, walk the differences and
/// fill the lookup tables.
void
enum_diff::ensure_lookup_tables_populated()
{
  if (!lookup_tables_empty())
    return;
 
  {
    edit_script e = priv_->enumerators_changes_;
 
    for (vector<deletion>::const_iterator it = e.deletions().begin();
     it != e.deletions().end();
     ++it)
      {
    unsigned i = it->index();
    const enum_type_decl::enumerator& n =
      first_enum()->get_enumerators()[i];
    const string& name = n.get_name();
    ABG_ASSERT(priv_->deleted_enumerators_.find(n.get_name())
           == priv_->deleted_enumerators_.end());
    priv_->deleted_enumerators_[name] = n;
      }
 
    for (vector<insertion>::const_iterator it = e.insertions().begin();
     it != e.insertions().end();
     ++it)
      {
    for (vector<unsigned>::const_iterator iit =
           it->inserted_indexes().begin();
         iit != it->inserted_indexes().end();
         ++iit)
      {
        unsigned i = *iit;
        const enum_type_decl::enumerator& n =
          second_enum()->get_enumerators()[i];
        const string& name = n.get_name();
        ABG_ASSERT(priv_->inserted_enumerators_.find(n.get_name())
           == priv_->inserted_enumerators_.end());
        string_enumerator_map::const_iterator j =
          priv_->deleted_enumerators_.find(name);
        if (j == priv_->deleted_enumerators_.end())
          priv_->inserted_enumerators_[name] = n;
        else
          {
        if (j->second != n)
          priv_->changed_enumerators_[j->first] =
            std::make_pair(j->second, n);
        priv_->deleted_enumerators_.erase(j);
          }
      }
      }
  }
}
 
/// Populate the vector of children node of the @ref diff base type
/// sub-object of this instance of @ref enum_diff.
///
/// The children node can then later be retrieved using
/// diff::children_node().
void
enum_diff::chain_into_hierarchy()
{append_child_node(underlying_type_diff());}
 
/// Constructor for enum_diff.
///
/// @param first the first enum type of the diff.
///
/// @param second the second enum type of the diff.
///
/// @param underlying_type_diff the diff of the two underlying types
/// of the two enum types.
///
/// @param ctxt the diff context to use.
enum_diff::enum_diff(const enum_type_decl_sptr  first,
             const enum_type_decl_sptr  second,
             const diff_sptr        underlying_type_diff,
             const diff_context_sptr    ctxt)
  : type_diff_base(first, second, ctxt),
    priv_(new priv(underlying_type_diff))
{}
 
/// @return the first enum of the diff.
const enum_type_decl_sptr
enum_diff::first_enum() const
{return dynamic_pointer_cast<enum_type_decl>(first_subject());}
 
/// @return the second enum of the diff.
const enum_type_decl_sptr
enum_diff::second_enum() const
{return dynamic_pointer_cast<enum_type_decl>(second_subject());}
 
/// @return the diff of the two underlying enum types.
diff_sptr
enum_diff::underlying_type_diff() const
{return priv_->underlying_type_diff_;}
 
/// @return a map of the enumerators that were deleted.
const string_enumerator_map&
enum_diff::deleted_enumerators() const
{return priv_->deleted_enumerators_;}
 
/// @return a map of the enumerators that were inserted
const string_enumerator_map&
enum_diff::inserted_enumerators() const
{return priv_->inserted_enumerators_;}
 
/// @return a map of the enumerators that were changed
const string_changed_enumerator_map&
enum_diff::changed_enumerators() const
{return priv_->changed_enumerators_;}
 
/// @return the pretty representation of the current instance of @ref
/// enum_diff.
const string&
enum_diff::get_pretty_representation() const
{
  if (diff::priv_->pretty_representation_.empty())
    {
      std::ostringstream o;
      o << "enum_diff["
    << first_subject()->get_pretty_representation()
    << ", "
    << second_subject()->get_pretty_representation()
    << "]";
      diff::priv_->pretty_representation_ = o.str();
    }
  return diff::priv_->pretty_representation_;
}
 
/// Return true iff the current diff node carries a change.
///
/// @return true iff the current diff node carries a change.
bool
enum_diff::has_changes() const
{return first_enum() != second_enum();}
 
/// @return the kind of local change carried by the current diff node.
/// The value returned is zero if the current node carries no local
/// change.
enum change_kind
enum_diff::has_local_changes() const
{
  ir::change_kind k = ir::NO_CHANGE_KIND;
  if (!equals(*first_enum(), *second_enum(), &k))
    return k & ir::ALL_LOCAL_CHANGES_MASK;
  return ir::NO_CHANGE_KIND;
}
 
/// Report the differences between the two enums.
///
/// @param out the output stream to send the report to.
///
/// @param indent the string to use for indentation.
void
enum_diff::report(ostream& out, const string& indent) const
{
  context()->get_reporter()->report(*this, out, indent);
}
 
/// Compute the set of changes between two instances of @ref
/// enum_type_decl.
///
/// Note that the two types must have been created in the same @ref
/// environment, otherwise, this function aborts.
///
/// @param first a pointer to the first enum_type_decl to consider.
///
/// @param second a pointer to the second enum_type_decl to consider.
///
/// @return the resulting diff of the two enums @p first and @p
/// second.
///
/// @param ctxt the diff context to use.
enum_diff_sptr
compute_diff(const enum_type_decl_sptr first,
         const enum_type_decl_sptr second,
         diff_context_sptr ctxt)
{
  diff_sptr ud = compute_diff_for_types(first->get_underlying_type(),
                    second->get_underlying_type(),
                    ctxt);
  enum_diff_sptr d(new enum_diff(first, second, ud, ctxt));
  if (first != second)
    {
      compute_diff(first->get_enumerators().begin(),
           first->get_enumerators().end(),
           second->get_enumerators().begin(),
           second->get_enumerators().end(),
           d->priv_->enumerators_changes_);
      d->ensure_lookup_tables_populated();
    }
  ctxt->initialize_canonical_diff(d);
 
  return d;
}
// </enum_diff stuff>
 
// <class_or_union_diff stuff>
 
/// Test if the current diff node carries a member type change for a
/// member type which name is the same as the name of a given type
/// declaration.
///
/// @param d the type declaration which name should be equal to the
/// name of the member type that might have changed.
///
/// @return the member type that has changed, iff there were a member
/// type (which name is the same as the name of @p d) that changed.
/// Note that the member type that is returned is the new value of the
/// member type that changed.
type_or_decl_base_sptr
class_or_union_diff::priv::member_type_has_changed(decl_base_sptr d) const
{
  string qname = d->get_qualified_name();
  string_diff_sptr_map::const_iterator it =
    changed_member_types_.find(qname);
 
  return ((it == changed_member_types_.end())
      ? type_or_decl_base_sptr()
      : it->second->second_subject());
}
 
/// Test if the current diff node carries a data member change for a
/// data member which name is the same as the name of a given type
/// declaration.
///
/// @param d the type declaration which name should be equal to the
/// name of the data member that might have changed.
///
/// @return the data member that has changed, iff there were a data
/// member type (which name is the same as the name of @p d) that
/// changed.  Note that the data member that is returned is the new
/// value of the data member that changed.
decl_base_sptr
class_or_union_diff::priv::subtype_changed_dm(decl_base_sptr d) const
{
  string qname = d->get_qualified_name();
  string_var_diff_sptr_map::const_iterator it =
    subtype_changed_dm_.find(qname);
 
  if (it == subtype_changed_dm_.end())
    return decl_base_sptr();
  return it->second->second_var();
}
 
/// Test if the current diff node carries a member class template
/// change for a member class template which name is the same as the
/// name of a given type declaration.
///
/// @param d the type declaration which name should be equal to the
/// name of the member class template that might have changed.
///
/// @return the member class template that has changed, iff there were
/// a member class template (which name is the same as the name of @p
/// d) that changed.  Note that the member class template that is
/// returned is the new value of the member class template that
/// changed.
decl_base_sptr
class_or_union_diff::priv::member_class_tmpl_has_changed(decl_base_sptr d) const
{
  string qname = d->get_qualified_name();
  string_diff_sptr_map::const_iterator it =
    changed_member_class_tmpls_.find(qname);
 
  return ((it == changed_member_class_tmpls_.end())
      ? decl_base_sptr()
      : dynamic_pointer_cast<decl_base>(it->second->second_subject()));
}
 
/// Get the number of non static data members that were deleted.
///
/// @return the number of non static data members that were deleted.
size_t
class_or_union_diff::priv::get_deleted_non_static_data_members_number() const
{
  size_t result = 0;
 
  for (string_decl_base_sptr_map::const_iterator i =
     deleted_data_members_.begin();
       i != deleted_data_members_.end();
       ++i)
    if (is_member_decl(i->second)
    && !get_member_is_static(i->second))
      ++result;
 
  return result;
}
 
/// Get the number of non static data members that were inserted.
///
/// @return the number of non static data members that were inserted.
size_t
class_or_union_diff::priv::get_inserted_non_static_data_members_number() const
{
  size_t result = 0;
 
  for (string_decl_base_sptr_map::const_iterator i =
     inserted_data_members_.begin();
       i != inserted_data_members_.end();
       ++i)
    if (is_member_decl(i->second)
    && !get_member_is_static(i->second))
      ++result;
 
  return result;
}
 
/// Get the number of data member sub-type changes carried by the
/// current diff node that were filtered out.
///
/// @param local_only if true, it means that only (filtered) local
/// changes are considered.
///
/// @return the number of data member sub-type changes carried by the
/// current diff node that were filtered out.
size_t
class_or_union_diff::priv::count_filtered_subtype_changed_dm(bool local_only)
{
  size_t num_filtered= 0;
  for (var_diff_sptrs_type::const_iterator i =
     sorted_subtype_changed_dm_.begin();
       i != sorted_subtype_changed_dm_.end();
       ++i)
    {
      if (local_only)
    {
      if ((*i)->has_changes()
          && !(*i)->has_local_changes_to_be_reported())
        ++num_filtered;
    }
      else
    {
      if ((*i)->is_filtered_out())
        ++num_filtered;
    }
    }
  return num_filtered;
}
 
/// Get the number of data member changes carried by the current diff
/// node that were filtered out.
///
/// @param local_only if true, it means that only (filtered) local
/// changes are considered.
///
/// @return the number of data member changes carried by the current
/// diff node that were filtered out.
size_t
class_or_union_diff::priv::count_filtered_changed_dm(bool local_only)
{
  size_t num_filtered= 0;
 
  for (unsigned_var_diff_sptr_map::const_iterator i = changed_dm_.begin();
       i != changed_dm_.end();
       ++i)
    {
      diff_sptr diff = i->second;
      if (local_only)
    {
      if ((diff->has_changes() && !diff->has_local_changes_to_be_reported())
          || diff->is_filtered_out())
        ++num_filtered;
    }
      else
    {
      if (diff->is_filtered_out())
        ++num_filtered;
    }
    }
  return num_filtered;
}
 
/// Skip the processing of the current member function if its
/// virtual-ness is disallowed by the user.
///
/// This is to be used in the member functions below that are used to
/// count the number of filtered inserted, deleted and changed member
/// functions.
#define SKIP_MEM_FN_IF_VIRTUALITY_DISALLOWED                \
  do {                                  \
    if (get_member_function_is_virtual(f)                   \
    || get_member_function_is_virtual(s))               \
      {                             \
    if (!(allowed_category | VIRTUAL_MEMBER_CHANGE_CATEGORY))   \
      continue;                         \
      }                             \
    else                                \
      {                             \
    if (!(allowed_category | NON_VIRT_MEM_FUN_CHANGE_CATEGORY)) \
      continue;                         \
      }                             \
  } while (false)
 
/// Get the number of member functions changes carried by the current
/// diff node that were filtered out.
///
/// @return the number of member functions changes carried by the
/// current diff node that were filtered out.
size_t
class_or_union_diff::priv::count_filtered_changed_mem_fns
(const diff_context_sptr& ctxt)
{
  size_t count = 0;
  diff_category allowed_category = ctxt->get_allowed_category();
 
  for (function_decl_diff_sptrs_type::const_iterator i =
     sorted_changed_member_functions_.begin();
       i != sorted_changed_member_functions_.end();
       ++i)
    {
      method_decl_sptr f =
    dynamic_pointer_cast<method_decl>
    ((*i)->first_function_decl());
      ABG_ASSERT(f);
 
      method_decl_sptr s =
    dynamic_pointer_cast<method_decl>
    ((*i)->second_function_decl());
      ABG_ASSERT(s);
 
      SKIP_MEM_FN_IF_VIRTUALITY_DISALLOWED;
 
      diff_sptr diff = *i;
      ctxt->maybe_apply_filters(diff);
 
      if (diff->is_filtered_out())
    ++count;
    }
 
  return count;
}
 
/// Get the number of member functions insertions carried by the current
/// diff node that were filtered out.
///
/// @return the number of member functions insertions carried by the
/// current diff node that were filtered out.
size_t
class_or_union_diff::priv::count_filtered_inserted_mem_fns
(const diff_context_sptr& ctxt)
{
    size_t count = 0;
  diff_category allowed_category = ctxt->get_allowed_category();
 
  for (string_member_function_sptr_map::const_iterator i =
     inserted_member_functions_.begin();
       i != inserted_member_functions_.end();
       ++i)
    {
      method_decl_sptr f = i->second,
    s = i->second;
 
      SKIP_MEM_FN_IF_VIRTUALITY_DISALLOWED;
 
      diff_sptr diff = compute_diff_for_decls(f, s, ctxt);
      ctxt->maybe_apply_filters(diff);
 
      if (diff->get_category() != NO_CHANGE_CATEGORY
      && diff->is_filtered_out())
    ++count;
    }
 
  return count;
}
 
/// Get the number of member functions deletions carried by the current
/// diff node that were filtered out.
///
/// @return the number of member functions deletions carried by the
/// current diff node that were filtered out.
size_t
class_or_union_diff::priv::count_filtered_deleted_mem_fns
(const diff_context_sptr& ctxt)
{
  size_t count = 0;
  diff_category allowed_category = ctxt->get_allowed_category();
 
  for (string_member_function_sptr_map::const_iterator i =
     deleted_member_functions_.begin();
       i != deleted_member_functions_.end();
       ++i)
    {
      method_decl_sptr f = i->second,
    s = i->second;
 
      SKIP_MEM_FN_IF_VIRTUALITY_DISALLOWED;
 
      diff_sptr diff = compute_diff_for_decls(f, s, ctxt);
      ctxt->maybe_apply_filters(diff);
 
      if (diff->get_category() != NO_CHANGE_CATEGORY
      && diff->is_filtered_out())
    ++count;
    }
 
  return count;
}
 
/// Clear the lookup tables useful for reporting.
///
/// This function must be updated each time a lookup table is added or
/// removed from the class_or_union_diff::priv.
void
class_or_union_diff::clear_lookup_tables()
{
  priv_->deleted_member_types_.clear();
  priv_->inserted_member_types_.clear();
  priv_->changed_member_types_.clear();
  priv_->deleted_data_members_.clear();
  priv_->inserted_data_members_.clear();
  priv_->subtype_changed_dm_.clear();
  priv_->deleted_member_functions_.clear();
  priv_->inserted_member_functions_.clear();
  priv_->changed_member_functions_.clear();
  priv_->deleted_member_class_tmpls_.clear();
  priv_->inserted_member_class_tmpls_.clear();
  priv_->changed_member_class_tmpls_.clear();
}
 
/// Tests if the lookup tables are empty.
///
/// @return true if the lookup tables are empty, false otherwise.
bool
class_or_union_diff::lookup_tables_empty(void) const
{
  return (priv_->deleted_member_types_.empty()
      && priv_->inserted_member_types_.empty()
      && priv_->changed_member_types_.empty()
      && priv_->deleted_data_members_.empty()
      && priv_->inserted_data_members_.empty()
      && priv_->subtype_changed_dm_.empty()
      && priv_->inserted_member_functions_.empty()
      && priv_->deleted_member_functions_.empty()
      && priv_->changed_member_functions_.empty()
      && priv_->deleted_member_class_tmpls_.empty()
      && priv_->inserted_member_class_tmpls_.empty()
      && priv_->changed_member_class_tmpls_.empty());
}
 
/// If the lookup tables are not yet built, walk the differences and
/// fill them.
void
class_or_union_diff::ensure_lookup_tables_populated(void) const
{
  {
    edit_script& e = priv_->member_types_changes_;
 
    for (vector<deletion>::const_iterator it = e.deletions().begin();
     it != e.deletions().end();
     ++it)
      {
    unsigned i = it->index();
    decl_base_sptr d =
      get_type_declaration(first_class_or_union()->get_member_types()[i]);
    class_or_union_sptr record_type = is_class_or_union_type(d);
    if (record_type && record_type->get_is_declaration_only())
      continue;
    string name = d->get_name();
    priv_->deleted_member_types_[name] = d;
      }
 
    for (vector<insertion>::const_iterator it = e.insertions().begin();
     it != e.insertions().end();
     ++it)
      {
    for (vector<unsigned>::const_iterator iit =
           it->inserted_indexes().begin();
         iit != it->inserted_indexes().end();
         ++iit)
      {
        unsigned i = *iit;
        decl_base_sptr d =
          get_type_declaration(second_class_or_union()->get_member_types()[i]);
        class_or_union_sptr record_type = is_class_or_union_type(d);
        if (record_type && record_type->get_is_declaration_only())
          continue;
        string name = d->get_name();
        string_decl_base_sptr_map::const_iterator j =
          priv_->deleted_member_types_.find(name);
        if (j != priv_->deleted_member_types_.end())
          {
        if (*j->second != *d)
          priv_->changed_member_types_[name] =
            compute_diff(j->second, d, context());
 
        priv_->deleted_member_types_.erase(j);
          }
        else
          priv_->inserted_member_types_[name] = d;
      }
      }
  }
 
  {
    edit_script& e = priv_->data_members_changes_;
 
    for (vector<deletion>::const_iterator it = e.deletions().begin();
     it != e.deletions().end();
     ++it)
      {
    unsigned i = it->index();
    var_decl_sptr data_member =
      is_var_decl(first_class_or_union()->get_non_static_data_members()[i]);
    string name = data_member->get_anon_dm_reliable_name();
 
    ABG_ASSERT(priv_->deleted_data_members_.find(name)
           == priv_->deleted_data_members_.end());
    priv_->deleted_data_members_[name] = data_member;
      }
 
    for (vector<insertion>::const_iterator it = e.insertions().begin();
     it != e.insertions().end();
     ++it)
      {
    for (vector<unsigned>::const_iterator iit =
           it->inserted_indexes().begin();
         iit != it->inserted_indexes().end();
         ++iit)
      {
        unsigned i = *iit;
        decl_base_sptr d =
          second_class_or_union()->get_non_static_data_members()[i];
        var_decl_sptr added_dm = is_var_decl(d);
        string name = added_dm->get_anon_dm_reliable_name();
        ABG_ASSERT(priv_->inserted_data_members_.find(name)
               == priv_->inserted_data_members_.end());
 
        bool ignore_added_anonymous_data_member = false;
        if (is_anonymous_data_member(added_dm))
          {
        //
        // Handle insertion of anonymous data member to
        // replace existing data members.
        //
        // For instance consider this:
        //   struct S
        //   {
        //     int a;
        //     int b;
        //     int c;
        //   };// end struct S
        //
        //   Where the data members 'a' and 'b' are replaced
        //   by an anonymous data member without changing the
        //   effective bit layout of the structure:
        //
        //   struct S
        //   {
        //     struct
        //     {
        //       union
        //       {
        //         int a;
        //         char a_1;
        //       };
        //       union
        //       {
        //         int b;
        //         char b_1;
        //       };
        //     };
        //     int c;
        //   }; // end struct S
        //
        var_decl_sptr replaced_dm, replacing_dm;
        bool added_anon_dm_changes_dm = false;
        // The vector of data members replaced by anonymous
        // data members.
        vector<var_decl_sptr> dms_replaced_by_anon_dm;
 
        //
        // Let's start collecting the set of data members
        // which have been replaced by anonymous types in a
        // harmless way.  These are going to be collected into
        // dms_replaced_by_anon_dm and, ultimately, into
        // priv_->dms_replaced_by_adms_
        //
        for (string_decl_base_sptr_map::const_iterator it =
               priv_->deleted_data_members_.begin();
             it != priv_->deleted_data_members_.end();
             ++it)
          {
            // We don't support this pattern for anonymous
            // data members themselves being replaced.  If
            // that occurs then we'll just report it verbatim.
            if (is_anonymous_data_member(it->second))
              continue;
 
            string deleted_dm_name = it->second->get_name();
            if ((replacing_dm =
             find_data_member_from_anonymous_data_member(added_dm,
                                     deleted_dm_name)))
              {
            // So it looks like replacing_dm might have
            // replaced the data member which name is
            // 'deleted_dm_name'.  Let's look deeper to be
            // sure.
            //
            // Note that replacing_dm is part (member) of
            // an anonymous data member that might replace
            // replaced_dm.
 
            // So let's get that replaced data member.
            replaced_dm = is_var_decl(it->second);
            size_t replaced_dm_offset =
              get_data_member_offset(replaced_dm),
            replacing_dm_offset =
              get_absolute_data_member_offset(replacing_dm);
 
            if (replaced_dm_offset != replacing_dm_offset)
              {
                // So the replacing data member and the
                // replaced data member don't have the
                // same offset.  This is not the pattern we
                // are looking for.  Rather, it looks like
                // the anonymous data member has *changed*
                // the data member.
                added_anon_dm_changes_dm = true;
                break;
              }
 
            if (replaced_dm->get_type()->get_size_in_bits()
                == replaced_dm->get_type()->get_size_in_bits())
              dms_replaced_by_anon_dm.push_back(replaced_dm);
            else
              {
                added_anon_dm_changes_dm = true;
                break;
              }
              }
          }
 
        // Now walk dms_replaced_by_anon_dm to fill up
        // priv_->dms_replaced_by_adms_ with the set of data
        // members replaced by anonymous data members.
        if (!added_anon_dm_changes_dm
            && !dms_replaced_by_anon_dm.empty())
          {
            // See if the added data member isn't too big.
            type_base_sptr added_dm_type = added_dm->get_type();
            ABG_ASSERT(added_dm_type);
            var_decl_sptr new_next_dm =
              get_next_data_member(second_class_or_union(),
                       added_dm);
            var_decl_sptr old_next_dm =
              first_class_or_union()->find_data_member(new_next_dm);
 
            if (!old_next_dm
            || (old_next_dm
                && (get_absolute_data_member_offset(old_next_dm)
                == get_absolute_data_member_offset(new_next_dm))))
              {
            // None of the data members that are replaced
            // by the added union should be considered as
            // having been deleted.
            ignore_added_anonymous_data_member = true;
            for (vector<var_decl_sptr>::const_iterator i =
                   dms_replaced_by_anon_dm.begin();
                 i != dms_replaced_by_anon_dm.end();
                 ++i)
              {
                string n = (*i)->get_name();
                priv_->dms_replaced_by_adms_[n] =
                  added_dm;
                priv_->deleted_data_members_.erase(n);
              }
              }
          }
          }
 
        if (!ignore_added_anonymous_data_member)
          {
        // Detect changed data members.
        //
        // A changed data member (that we shall name D) is a data
        // member that satisfies the conditions below:
        //
        // 1/ It must have been added.
        //
        // 2/ It must have been deleted as well.
        //
        // 3/ It there must be a non-empty difference between the
        // deleted D and the added D.
        string_decl_base_sptr_map::const_iterator j =
          priv_->deleted_data_members_.find(name);
        if (j != priv_->deleted_data_members_.end())
          {
            if (*j->second != *d)
              {
            var_decl_sptr old_dm = is_var_decl(j->second);
            priv_->subtype_changed_dm_[name]=
              compute_diff(old_dm, added_dm, context());
              }
            priv_->deleted_data_members_.erase(j);
          }
        else
          priv_->inserted_data_members_[name] = d;
          }
      }
      }
 
    // Now detect when a data member is deleted from offset N and
    // another one is added to offset N.  In that case, we want to be
    // able to say that the data member at offset N changed.
    for (string_decl_base_sptr_map::const_iterator i =
       priv_->deleted_data_members_.begin();
     i != priv_->deleted_data_members_.end();
     ++i)
      {
    unsigned offset = get_data_member_offset(i->second);
    priv_->deleted_dm_by_offset_[offset] = i->second;
      }
 
    for (string_decl_base_sptr_map::const_iterator i =
       priv_->inserted_data_members_.begin();
     i != priv_->inserted_data_members_.end();
     ++i)
      {
    unsigned offset = get_data_member_offset(i->second);
    priv_->inserted_dm_by_offset_[offset] = i->second;
      }
 
    for (unsigned_decl_base_sptr_map::const_iterator i =
       priv_->inserted_dm_by_offset_.begin();
     i != priv_->inserted_dm_by_offset_.end();
     ++i)
      {
    unsigned_decl_base_sptr_map::const_iterator j =
      priv_->deleted_dm_by_offset_.find(i->first);
    if (j != priv_->deleted_dm_by_offset_.end())
      {
        var_decl_sptr old_dm = is_var_decl(j->second);
        var_decl_sptr new_dm = is_var_decl(i->second);
        priv_->changed_dm_[i->first] =
          compute_diff(old_dm, new_dm, context());
      }
      }
 
    for (unsigned_var_diff_sptr_map::const_iterator i =
       priv_->changed_dm_.begin();
     i != priv_->changed_dm_.end();
     ++i)
      {
    priv_->deleted_dm_by_offset_.erase(i->first);
    priv_->inserted_dm_by_offset_.erase(i->first);
    priv_->deleted_data_members_.erase
      (i->second->first_var()->get_anon_dm_reliable_name());
    priv_->inserted_data_members_.erase
      (i->second->second_var()->get_anon_dm_reliable_name());
      }
  }
  sort_string_data_member_diff_sptr_map(priv_->subtype_changed_dm_,
                    priv_->sorted_subtype_changed_dm_);
  sort_unsigned_data_member_diff_sptr_map(priv_->changed_dm_,
                      priv_->sorted_changed_dm_);
 
  {
    edit_script& e = priv_->member_class_tmpls_changes_;
 
    for (vector<deletion>::const_iterator it = e.deletions().begin();
     it != e.deletions().end();
     ++it)
      {
    unsigned i = it->index();
    decl_base_sptr d =
      first_class_or_union()->get_member_class_templates()[i]->
      as_class_tdecl();
    string name = d->get_name();
    ABG_ASSERT(priv_->deleted_member_class_tmpls_.find(name)
           == priv_->deleted_member_class_tmpls_.end());
    priv_->deleted_member_class_tmpls_[name] = d;
      }
 
    for (vector<insertion>::const_iterator it = e.insertions().begin();
     it != e.insertions().end();
     ++it)
      {
    for (vector<unsigned>::const_iterator iit =
           it->inserted_indexes().begin();
         iit != it->inserted_indexes().end();
         ++iit)
      {
        unsigned i = *iit;
        decl_base_sptr d =
          second_class_or_union()->get_member_class_templates()[i]->
          as_class_tdecl();
        string name = d->get_name();
        ABG_ASSERT(priv_->inserted_member_class_tmpls_.find(name)
           == priv_->inserted_member_class_tmpls_.end());
        string_decl_base_sptr_map::const_iterator j =
          priv_->deleted_member_class_tmpls_.find(name);
        if (j != priv_->deleted_member_class_tmpls_.end())
          {
        if (*j->second != *d)
          priv_->changed_member_types_[name]=
            compute_diff(j->second, d, context());
        priv_->deleted_member_class_tmpls_.erase(j);
          }
        else
          priv_->inserted_member_class_tmpls_[name] = d;
      }
      }
  }
  sort_string_diff_sptr_map(priv_->changed_member_types_,
                priv_->sorted_changed_member_types_);
}
 
/// Allocate the memory for the priv_ pimpl data member of the @ref
/// class_or_union_diff class.
void
class_or_union_diff::allocate_priv_data()
{
  if (!priv_)
    priv_.reset(new priv);
}
 
/// Constructor for the @ref class_or_union_diff class.
///
/// @param first_scope the first @ref class_or_union of the diff node.
///
/// @param second_scope the second @ref class_or_union of the diff node.
///
/// @param ctxt the context of the diff.
class_or_union_diff::class_or_union_diff(class_or_union_sptr first_scope,
                     class_or_union_sptr second_scope,
                     diff_context_sptr ctxt)
  : type_diff_base(first_scope, second_scope, ctxt)
    //priv_(new priv)
{}
 
/// Getter of the private data of the @ref class_or_union_diff type.
///
/// Note that due to an optimization, the private data of @ref
/// class_or_union_diff can be shared among several instances of
/// class_or_union_diff, so you should never try to access
/// class_or_union_diff::priv directly.
///
/// When class_or_union_diff::priv is shared, this function returns
/// the correct shared one.
///
/// @return the (possibly) shared private data of the current instance
/// of @ref class_or_union_diff.
const class_or_union_diff::priv_ptr&
class_or_union_diff::get_priv() const
{
  if (priv_)
    return priv_;
 
  // If the current class_or_union_diff::priv member is empty, then look for
  // the shared one, from the canonical type.
  class_or_union_diff *canonical =
    dynamic_cast<class_or_union_diff*>(get_canonical_diff());
  ABG_ASSERT(canonical);
  ABG_ASSERT(canonical->priv_);
 
  return canonical->priv_;
}
 
/// Destructor of class_or_union_diff.
class_or_union_diff::~class_or_union_diff()
{
}
 
/// @return the first @ref class_or_union involved in the diff.
class_or_union_sptr
class_or_union_diff::first_class_or_union() const
{return is_class_or_union_type(first_subject());}
 
/// @return the second @ref class_or_union involved in the diff.
class_or_union_sptr
class_or_union_diff::second_class_or_union() const
{return is_class_or_union_type(second_subject());}
 
/// @return the edit script of the member types of the two @ref
/// class_or_union.
const edit_script&
class_or_union_diff::member_types_changes() const
{return get_priv()->member_types_changes_;}
 
/// @return the edit script of the member types of the two @ref
/// class_or_union.
edit_script&
class_or_union_diff::member_types_changes()
{return get_priv()->member_types_changes_;}
 
/// @return the edit script of the data members of the two @ref
/// class_or_union.
const edit_script&
class_or_union_diff::data_members_changes() const
{return get_priv()->data_members_changes_;}
 
/// @return the edit script of the data members of the two @ref
/// class_or_union.
edit_script&
class_or_union_diff::data_members_changes()
{return get_priv()->data_members_changes_;}
 
/// Getter for the data members that got inserted.
///
/// @return a map of data members that got inserted.
const string_decl_base_sptr_map&
class_or_union_diff::inserted_data_members() const
{return get_priv()->inserted_data_members_;}
 
/// Getter for the data members that got deleted.
///
/// @return a map of data members that got deleted.
const string_decl_base_sptr_map&
class_or_union_diff::deleted_data_members() const
{return get_priv()->deleted_data_members_;}
 
/// @return the edit script of the member functions of the two @ref
/// class_or_union.
const edit_script&
class_or_union_diff::member_fns_changes() const
{return get_priv()->member_fns_changes_;}
 
/// Getter for the virtual members functions that have had a change in
/// a sub-type, without having a change in their symbol name.
///
/// @return a sorted vector of virtual member functions that have a
/// sub-type change.
const function_decl_diff_sptrs_type&
class_or_union_diff::changed_member_fns() const
{return get_priv()->sorted_changed_member_functions_;}
 
/// @return the edit script of the member functions of the two
/// classes.
edit_script&
class_or_union_diff::member_fns_changes()
{return get_priv()->member_fns_changes_;}
 
/// @return a map of member functions that got deleted.
const string_member_function_sptr_map&
class_or_union_diff::deleted_member_fns() const
{return get_priv()->deleted_member_functions_;}
 
/// @return a map of member functions that got inserted.
const string_member_function_sptr_map&
class_or_union_diff::inserted_member_fns() const
{return get_priv()->inserted_member_functions_;}
 
/// Getter of the sorted vector of data members that got replaced by
/// another data member.
///
/// @return sorted vector of changed data member.
const var_diff_sptrs_type&
class_or_union_diff::sorted_changed_data_members() const
{return get_priv()->sorted_changed_dm_;}
 
/// Count the number of /filtered/ data members that got replaced by
/// another data member.
///
/// @return the number of changed data member that got filtered out.
size_t
class_or_union_diff::count_filtered_changed_data_members(bool local) const
{return get_priv()->count_filtered_changed_dm(local);}
 
/// Getter of the sorted vector of data members with a (sub-)type change.
///
/// @return sorted vector of changed data member.
const var_diff_sptrs_type&
class_or_union_diff::sorted_subtype_changed_data_members() const
{return get_priv()->sorted_subtype_changed_dm_;}
 
/// Count the number of /filtered/ data members with a sub-type change.
///
/// @return the number of changed data member that got filtered out.
size_t
class_or_union_diff::count_filtered_subtype_changed_data_members(bool local) const
{return get_priv()->count_filtered_subtype_changed_dm(local);}
 
/// Get the map of data members that got replaced by anonymous data
/// members.
///
/// The key of a map entry is the name of the replaced data member and
/// the value is the anonymous data member that replaces it.
///
/// @return the map of data members replaced by anonymous data
/// members.
const string_decl_base_sptr_map&
class_or_union_diff::data_members_replaced_by_adms() const
{return get_priv()->dms_replaced_by_adms_;}
 
/// Get an ordered vector of of data members that got replaced by
/// anonymous data members.
///
/// This returns a vector of pair of two data members: the one that
/// was replaced, and the anonymous data member that replaced it.
///
/// @return the sorted vector data members replaced by anonymous data members.
const changed_var_sptrs_type&
class_or_union_diff::ordered_data_members_replaced_by_adms() const
{
  if (priv_->dms_replaced_by_adms_ordered_.empty())
    {
      for (string_decl_base_sptr_map::const_iterator it =
         priv_->dms_replaced_by_adms_.begin();
       it != priv_->dms_replaced_by_adms_.end();
       ++it)
    {
      const var_decl_sptr dm =
        first_class_or_union()->find_data_member(it->first);
      ABG_ASSERT(dm);
      changed_var_sptr changed_dm(dm, is_data_member(it->second));
      priv_->dms_replaced_by_adms_ordered_.push_back(changed_dm);
    }
      sort_changed_data_members(priv_->dms_replaced_by_adms_ordered_);
    }
 
  return priv_->dms_replaced_by_adms_ordered_;
}
 
/// @return the edit script of the member function templates of the two
/// @ref class_or_union.
const edit_script&
class_or_union_diff::member_fn_tmpls_changes() const
{return get_priv()->member_fn_tmpls_changes_;}
 
/// @return the edit script of the member function templates of the
/// two @ref class_or_union.
edit_script&
class_or_union_diff::member_fn_tmpls_changes()
{return get_priv()->member_fn_tmpls_changes_;}
 
/// @return the edit script of the member class templates of the two
/// @ref class_or_union.
const edit_script&
class_or_union_diff::member_class_tmpls_changes() const
{return get_priv()->member_class_tmpls_changes_;}
 
/// @return the edit script of the member class templates of the two
/// @ref class_or_union.
edit_script&
class_or_union_diff::member_class_tmpls_changes()
{return get_priv()->member_class_tmpls_changes_;}
 
/// Test if the current diff node carries a change.
bool
class_or_union_diff::has_changes() const
{return first_class_or_union() != second_class_or_union();}
 
/// @return the kind of local change carried by the current diff node.
/// The value returned is zero if the current node carries no local
/// change.
enum change_kind
class_or_union_diff::has_local_changes() const
{
  ir::change_kind k = ir::NO_CHANGE_KIND;
  if (!equals(*first_class_or_union(), *second_class_or_union(), &k))
    return k & ir::ALL_LOCAL_CHANGES_MASK;
  return ir::NO_CHANGE_KIND;
}
 
 
/// Report the changes carried by the current @ref class_or_union_diff
/// node in a textual format.
///
/// @param out the output stream to write the textual report to.
///
/// @param indent the number of white space to use as indentation.
void
class_or_union_diff::report(ostream& out, const string& indent) const
{
  context()->get_reporter()->report(*this, out, indent);
}
 
/// Populate the vector of children node of the @ref diff base type
/// sub-object of this instance of @ref class_or_union_diff.
///
/// The children node can then later be retrieved using
/// diff::children_node().
void
class_or_union_diff::chain_into_hierarchy()
{
  // data member changes
  for (var_diff_sptrs_type::const_iterator i =
     get_priv()->sorted_subtype_changed_dm_.begin();
       i != get_priv()->sorted_subtype_changed_dm_.end();
       ++i)
    if (diff_sptr d = *i)
      append_child_node(d);
 
  for (var_diff_sptrs_type::const_iterator i =
     get_priv()->sorted_changed_dm_.begin();
       i != get_priv()->sorted_changed_dm_.end();
       ++i)
    if (diff_sptr d = *i)
      append_child_node(d);
 
  // member types changes
  for (diff_sptrs_type::const_iterator i =
     get_priv()->sorted_changed_member_types_.begin();
       i != get_priv()->sorted_changed_member_types_.end();
       ++i)
    if (diff_sptr d = *i)
      append_child_node(d);
 
  // member function changes
  for (function_decl_diff_sptrs_type::const_iterator i =
     get_priv()->sorted_changed_member_functions_.begin();
       i != get_priv()->sorted_changed_member_functions_.end();
       ++i)
    if (diff_sptr d = *i)
      append_child_node(d);
}
 
// </class_or_union_diff stuff>
 
//<class_diff stuff>
 
/// Clear the lookup tables useful for reporting.
///
/// This function must be updated each time a lookup table is added or
/// removed from the class_diff::priv.
void
class_diff::clear_lookup_tables(void)
{
  priv_->deleted_bases_.clear();
  priv_->inserted_bases_.clear();
  priv_->changed_bases_.clear();
}
 
/// Tests if the lookup tables are empty.
///
/// @return true if the lookup tables are empty, false otherwise.
bool
class_diff::lookup_tables_empty(void) const
{
  return (priv_->deleted_bases_.empty()
      && priv_->inserted_bases_.empty()
      && priv_->changed_bases_.empty());
}
 
/// Find a virtual destructor in a map of member functions
///
/// @param map the map of member functions.  Note that the key of the
/// map is the member function name.  The key is the member function.
///
/// @return an iterator to the destructor found or, if no virtual destructor
/// was found, return map.end()
static string_member_function_sptr_map::const_iterator
find_virtual_dtor_in_map(const string_member_function_sptr_map& map)
{
  for (string_member_function_sptr_map::const_iterator i = map.begin();
       i !=map.end();
       ++i)
    {
      if (get_member_function_is_dtor(i->second)
      && get_member_function_is_virtual(i->second))
    return i;
    }
  return map.end();
}
 
/// If the lookup tables are not yet built, walk the differences and
/// fill them.
void
class_diff::ensure_lookup_tables_populated(void) const
{
  class_or_union_diff::ensure_lookup_tables_populated();
 
  if (!lookup_tables_empty())
    return;
 
  {
    edit_script& e = get_priv()->base_changes_;
 
    for (vector<deletion>::const_iterator it = e.deletions().begin();
     it != e.deletions().end();
     ++it)
      {
    unsigned i = it->index();
    class_decl::base_spec_sptr b =
      first_class_decl()->get_base_specifiers()[i];
    string name = b->get_base_class()->get_qualified_name();
    ABG_ASSERT(get_priv()->deleted_bases_.find(name)
           == get_priv()->deleted_bases_.end());
    get_priv()->deleted_bases_[name] = b;
      }
 
    for (vector<insertion>::const_iterator it = e.insertions().begin();
     it != e.insertions().end();
     ++it)
      {
    for (vector<unsigned>::const_iterator iit =
           it->inserted_indexes().begin();
         iit != it->inserted_indexes().end();
         ++iit)
      {
        unsigned i = *iit;
        class_decl::base_spec_sptr b =
          second_class_decl()->get_base_specifiers()[i];
        string name = b->get_base_class()->get_qualified_name();
        ABG_ASSERT(get_priv()->inserted_bases_.find(name)
           == get_priv()->inserted_bases_.end());
        string_base_sptr_map::const_iterator j =
          get_priv()->deleted_bases_.find(name);
        if (j != get_priv()->deleted_bases_.end())
          {
        if (j->second != b)
          get_priv()->changed_bases_[name] =
            compute_diff(j->second, b, context());
        else
          // The base class changed place.  IOW, the base
          // classes got re-arranged.  Let's keep track of the
          // base classes that moved.
          get_priv()->moved_bases_.push_back(b);
        get_priv()->deleted_bases_.erase(j);
          }
        else
          get_priv()->inserted_bases_[name] = b;
      }
      }
  }
 
  sort_string_base_sptr_map(get_priv()->deleted_bases_,
                get_priv()->sorted_deleted_bases_);
  sort_string_base_sptr_map(get_priv()->inserted_bases_,
                get_priv()->sorted_inserted_bases_);
  sort_string_base_diff_sptr_map(get_priv()->changed_bases_,
                 get_priv()->sorted_changed_bases_);
 
  {
    const class_or_union_diff::priv_ptr &p = class_or_union_diff::get_priv();
 
    edit_script& e = p->member_fns_changes_;
 
    for (vector<deletion>::const_iterator it = e.deletions().begin();
     it != e.deletions().end();
     ++it)
      {
    unsigned i = it->index();
    method_decl_sptr mem_fn =
      first_class_decl()->get_virtual_mem_fns()[i];
    string name = mem_fn->get_linkage_name();
    if (name.empty())
      name = mem_fn->get_pretty_representation();
    ABG_ASSERT(!name.empty());
    if (p->deleted_member_functions_.find(name)
        != p->deleted_member_functions_.end())
      continue;
    p->deleted_member_functions_[name] = mem_fn;
      }
 
    for (vector<insertion>::const_iterator it = e.insertions().begin();
     it != e.insertions().end();
     ++it)
      {
    for (vector<unsigned>::const_iterator iit =
           it->inserted_indexes().begin();
         iit != it->inserted_indexes().end();
         ++iit)
      {
        unsigned i = *iit;
 
        method_decl_sptr mem_fn =
          second_class_decl()->get_virtual_mem_fns()[i];
        string name = mem_fn->get_linkage_name();
        if (name.empty())
          name = mem_fn->get_pretty_representation();
        ABG_ASSERT(!name.empty());
        if (p->inserted_member_functions_.find(name)
        != p->inserted_member_functions_.end())
          continue;
        string_member_function_sptr_map::const_iterator j =
          p->deleted_member_functions_.find(name);
 
        if (j != p->deleted_member_functions_.end())
          {
        if (*j->second != *mem_fn)
          p->changed_member_functions_[name] =
            compute_diff(static_pointer_cast<function_decl>(j->second),
                 static_pointer_cast<function_decl>(mem_fn),
                 context());
        p->deleted_member_functions_.erase(j);
          }
        else
          p->inserted_member_functions_[name] = mem_fn;
      }
      }
 
    // Now walk the allegedly deleted member functions; check if their
    // underlying symbols are deleted as well; otherwise, consider
    // that the member function in question hasn't been deleted.
 
    // Also, while walking the deleted member functions, we attend at
    // a particular cleanup business related to (virtual) C++
    // destructors:
    //
    // In the binary, there can be at least three types of
    // destructors, defined in the document
    // https://itanium-cxx-abi.github.io/cxx-abi/abi.html#definitions:
    //
    //   1/ Base object destructor (aka D2 destructor):
    //
    //      "A function that runs the destructors for non-static data
    //      members of T and non-virtual direct base classes of T. "
    //
    //   2/ Complete object destructor (aka D1 destructor):
    //
    //      "A function that, in addition to the actions required of a
    //      base object destructor, runs the destructors for the
    //      virtual base classes of T."
    //
    //   3/ Deleting destructor (aka D0 destructor):
    //
    //      "A function that, in addition to the actions required of a
    //      complete object destructor, calls the appropriate
    //      deallocation function (i.e,. operator delete) for T."
    //
    // With binaries generated by GCC, these destructors might be ELF
    // clones of each others, meaning, their ELF symbols can be
    // aliases.
    //
    // Also, note that because the actual destructor invoked by user
    // code is virtual, it's invoked through the vtable.  So the
    // presence of the underlying D0, D1, D2 in the binary might vary
    // without that variation being an ABI issue, provided that the
    // destructor invoked through the vtable is present.
    //
    // So, a particular virtual destructor implementation for a class
    // might disapear and be replaced by another one in a subsequent
    // version of the binary.  If all versions of the binary have an
    // actual virtual destructor, things might be considered fine.
    vector<string> to_delete;
    corpus_sptr f = context()->get_first_corpus(),
      s = context()->get_second_corpus();
    if (s)
      for (string_member_function_sptr_map::const_iterator i =
         deleted_member_fns().begin();
       i != deleted_member_fns().end();
       ++i)
    {
      if (get_member_function_is_virtual(i->second))
        {
          if (get_member_function_is_dtor(i->second))
        {
          // If a particular virtual destructor is deleted,
          // but the new binary still have a virtual
          // destructor for that class we consider that things
          // are fine.  For instance, in the
          // tests/data/test-diff-pkg/tbb-4.1-9.20130314.fc22.x86_64--tbb-4.3-3.20141204.fc23.x86_64-report-0.txt
          // test, a new D4 destructor replaces the old ones.
          // But because the virtual destructor is still
          // there, this is not an ABI issue.  So let's detect
          // this case.
          auto it =
            find_virtual_dtor_in_map(p->inserted_member_functions_);
          if (it != p->inserted_member_functions_.end())
            {
              // So the deleted virtual destructor is not
              // really deleted, because a proper virtual
              // destructor was added to the new version.
              // Let's remove the deleted/added virtual
              // destructor then.
              string name =
            (!i->second->get_linkage_name().empty())
            ? i->second->get_linkage_name()
            : i->second->get_pretty_representation();
              to_delete.push_back(name);
              p->inserted_member_functions_.erase(it);
            }
        }
          continue;
        }
      // We assume that all non-virtual member functions functions
      // we look at here have ELF symbols.
      if (!i->second->get_symbol()
          || s->lookup_function_symbol(*i->second->get_symbol()))
        to_delete.push_back(i->first);
    }
 
 
    for (vector<string>::const_iterator i = to_delete.begin();
     i != to_delete.end();
     ++i)
      p->deleted_member_functions_.erase(*i);
 
    // Do something similar for added functions.
    to_delete.clear();
    if (f)
      for (string_member_function_sptr_map::const_iterator i =
         inserted_member_fns().begin();
       i != inserted_member_fns().end();
       ++i)
    {
      if (get_member_function_is_virtual(i->second))
        continue;
      // We assume that all non-virtual member functions functions
      // we look at here have ELF symbols.
      if (!i->second->get_symbol()
          || f->lookup_function_symbol(*i->second->get_symbol()))
        to_delete.push_back(i->first);
    }
 
    for (vector<string>::const_iterator i = to_delete.begin();
     i != to_delete.end();
     ++i)
      p->inserted_member_functions_.erase(*i);
 
    sort_string_member_function_sptr_map(p->deleted_member_functions_,
                     p->sorted_deleted_member_functions_);
 
    sort_string_member_function_sptr_map(p->inserted_member_functions_,
                     p->sorted_inserted_member_functions_);
 
    sort_string_virtual_member_function_diff_sptr_map
      (p->changed_member_functions_,
       p->sorted_changed_member_functions_);
  }
}
 
/// Allocate the memory for the priv_ pimpl data member of the @ref
/// class_diff class.
void
class_diff::allocate_priv_data()
{
  class_or_union_diff::allocate_priv_data();
  if (!priv_)
    priv_.reset(new priv);
}
 
/// Test whether a given base class has changed.  A base class has
/// changed if it's in both in deleted *and* inserted bases.
///
///@param d the declaration for the base class to consider.
///
/// @return the new base class if the given base class has changed, or
/// NULL if it hasn't.
class_decl::base_spec_sptr
class_diff::priv::base_has_changed(class_decl::base_spec_sptr d) const
{
  string qname = d->get_base_class()->get_qualified_name();
  string_base_diff_sptr_map::const_iterator it =
    changed_bases_.find(qname);
 
  return (it == changed_bases_.end())
    ? class_decl::base_spec_sptr()
    : it->second->second_base();
 
}
 
/// Count the number of bases classes whose changes got filtered out.
///
/// @return the number of bases classes whose changes got filtered
/// out.
size_t
class_diff::priv::count_filtered_bases()
{
  size_t num_filtered = 0;
  for (base_diff_sptrs_type::const_iterator i = sorted_changed_bases_.begin();
       i != sorted_changed_bases_.end();
       ++i)
    {
      diff_sptr diff = *i;
      if (diff && diff->is_filtered_out())
    ++num_filtered;
    }
  return num_filtered;
}
 
/// Populate the vector of children node of the @ref diff base type
/// sub-object of this instance of @ref class_diff.
///
/// The children node can then later be retrieved using
/// diff::children_node().
void
class_diff::chain_into_hierarchy()
{
  class_or_union_diff::chain_into_hierarchy();
 
  // base class changes.
  for (base_diff_sptrs_type::const_iterator i =
     get_priv()->sorted_changed_bases_.begin();
       i != get_priv()->sorted_changed_bases_.end();
       ++i)
    if (diff_sptr d = *i)
      append_child_node(d);
}
 
/// Constructor of class_diff
///
/// @param first_scope the first class of the diff.
///
/// @param second_scope the second class of the diff.
///
/// @param ctxt the diff context to use.
class_diff::class_diff(class_decl_sptr first_scope,
               class_decl_sptr second_scope,
               diff_context_sptr ctxt)
  : class_or_union_diff(first_scope, second_scope, ctxt)
    //  We don't initialize the priv_ data member here.  This is an
    //  optimization to reduce memory consumption (and also execution
    //  time) for cases where there are a lot of instances of
    //  class_diff in the same equivalence class.  In compute_diff(),
    //  the priv_ is set to the priv_ of the canonical diff node.
    //  See PR libabigail/17948.
{}
 
class_diff::~class_diff()
{}
 
/// Getter of the private data of the @ref class_diff type.
///
/// Note that due to an optimization, the private data of @ref
/// class_diff can be shared among several instances of class_diff, so
/// you should never try to access class_diff::priv directly.
///
/// When class_diff::priv is shared, this function returns the correct
/// shared one.
///
/// @return the (possibly) shared private data of the current instance
/// of class_diff.
const class_diff::priv_ptr&
class_diff::get_priv() const
{
  if (priv_)
    return priv_;
 
  // If the current class_diff::priv member is empty, then look for
  // the shared one, from the canonical type.
  class_diff *canonical =
    dynamic_cast<class_diff*>(get_canonical_diff());
  ABG_ASSERT(canonical);
  ABG_ASSERT(canonical->priv_);
 
  return canonical->priv_;
}
 
/// @return the pretty representation of the current instance of @ref
/// class_diff.
const string&
class_diff::get_pretty_representation() const
{
  if (diff::priv_->pretty_representation_.empty())
    {
      std::ostringstream o;
      o << "class_diff["
    << first_subject()->get_pretty_representation()
    << ", "
    << second_subject()->get_pretty_representation()
    << "]";
      diff::priv_->pretty_representation_ = o.str();
    }
  return diff::priv_->pretty_representation_;
}
 
/// Return true iff the current diff node carries a change.
///
/// @return true iff the current diff node carries a change.
bool
class_diff::has_changes() const
{return (first_class_decl() != second_class_decl());}
 
/// @return the kind of local change carried by the current diff node.
/// The value returned is zero if the current node carries no local
/// change.
enum change_kind
class_diff::has_local_changes() const
{
  ir::change_kind k = ir::NO_CHANGE_KIND;
  if (!equals(*first_class_decl(), *second_class_decl(), &k))
    return k & ir::ALL_LOCAL_CHANGES_MASK;
  return ir::NO_CHANGE_KIND;
}
 
/// @return the first class invoveld in the diff.
shared_ptr<class_decl>
class_diff::first_class_decl() const
{return dynamic_pointer_cast<class_decl>(first_subject());}
 
/// Getter of the second class involved in the diff.
///
/// @return the second class invoveld in the diff
shared_ptr<class_decl>
class_diff::second_class_decl() const
{return dynamic_pointer_cast<class_decl>(second_subject());}
 
/// @return the edit script of the bases of the two classes.
const edit_script&
class_diff::base_changes() const
{return get_priv()->base_changes_;}
 
/// Getter for the deleted base classes of the diff.
///
/// @return a map containing the deleted base classes, keyed with
/// their pretty representation.
const string_base_sptr_map&
class_diff::deleted_bases() const
{return get_priv()->deleted_bases_;}
 
/// Getter for the inserted base classes of the diff.
///
/// @return a map containing the inserted base classes, keyed with
/// their pretty representation.
const string_base_sptr_map&
class_diff::inserted_bases() const
{return get_priv()->inserted_bases_;}
 
/// Getter for the changed base classes of the diff.
///
/// @return a sorted vector containing the changed base classes
const base_diff_sptrs_type&
class_diff::changed_bases()
{return get_priv()->sorted_changed_bases_;}
 
/// Getter for the vector of bases that "moved".
/// That is, the vector of base types which position changed.  If this
/// vector is not empty, it means the bases of the underlying class
/// type got re-ordered.
///
/// @return the vector of bases that moved.
const vector<class_decl::base_spec_sptr>&
class_diff::moved_bases() const
{return get_priv()->moved_bases_;}
 
/// @return the edit script of the bases of the two classes.
edit_script&
class_diff::base_changes()
{return get_priv()->base_changes_;}
 
/// Produce a basic report about the changes between two class_decl.
///
/// @param out the output stream to report the changes to.
///
/// @param indent the string to use as an indentation prefix in the
/// report.
void
class_diff::report(ostream& out, const string& indent) const
{
  context()->get_reporter()->report(*this, out, indent);
}
 
/// Compute the set of changes between two instances of class_decl.
///
/// Note that the two types must have been created in the same @ref
/// environment, otherwise, this function aborts.
///
/// @param first the first class_decl to consider.
///
/// @param second the second class_decl to consider.
///
/// @return changes the resulting changes.
///
/// @param ctxt the diff context to use.
class_diff_sptr
compute_diff(const class_decl_sptr  first,
         const class_decl_sptr  second,
         diff_context_sptr      ctxt)
{
  class_decl_sptr f = is_class_type(look_through_decl_only_class(first)),
    s = is_class_type(look_through_decl_only_class(second));
 
  class_diff_sptr changes(new class_diff(f, s, ctxt));
 
  ctxt->initialize_canonical_diff(changes);
  ABG_ASSERT(changes->get_canonical_diff());
 
  if (!ctxt->get_canonical_diff_for(first, second))
    {
      // Either first or second is a decl-only class; let's set the
      // canonical diff here in that case.
      diff_sptr canonical_diff = ctxt->get_canonical_diff_for(changes);
      ABG_ASSERT(canonical_diff);
      ctxt->set_canonical_diff_for(first, second, canonical_diff);
    }
 
  // Ok, so this is an optimization.  Do not freak out if it looks
  // weird, because, well, it does look weird.  This speeds up
  // greatly, for instance, the test case given at PR
  // libabigail/17948.
  //
  // We are setting the private data of the new instance of class_diff
  // (which is 'changes') to the private data of its canonical
  // instance.  That is, we are sharing the private data of 'changes'
  // with the private data of its canonical instance to consume less
  // memory in cases where the equivalence class of 'changes' is huge.
  //
  // But if changes is its own canonical instance, then we initialize
  // its private data properly
  if (is_class_diff(changes->get_canonical_diff()) == changes.get())
    // changes is its own canonical instance, so it gets a brand new
    // private data.
    changes->allocate_priv_data();
  else
    {
      // changes has a non-empty equivalence class so it's going to
      // share its private data with its canonical instance.  Next
      // time class_diff::get_priv() is invoked, it's going to return
      // the shared private data of the canonical instance.
      return changes;
    }
 
  // Compare base specs
  compute_diff(f->get_base_specifiers().begin(),
           f->get_base_specifiers().end(),
           s->get_base_specifiers().begin(),
           s->get_base_specifiers().end(),
           changes->base_changes());
 
  // Do *not* compare member types because it generates lots of noise
  // and I doubt it's really useful.
#if 0
  compute_diff(f->get_member_types().begin(),
           f->get_member_types().end(),
           s->get_member_types().begin(),
           s->get_member_types().end(),
           changes->member_types_changes());
#endif
 
  // Compare data member
  compute_diff(f->get_non_static_data_members().begin(),
           f->get_non_static_data_members().end(),
           s->get_non_static_data_members().begin(),
           s->get_non_static_data_members().end(),
           changes->data_members_changes());
 
  // Compare virtual member functions
  compute_diff(f->get_virtual_mem_fns().begin(),
           f->get_virtual_mem_fns().end(),
           s->get_virtual_mem_fns().begin(),
           s->get_virtual_mem_fns().end(),
           changes->member_fns_changes());
 
  // Compare member function templates
  compute_diff(f->get_member_function_templates().begin(),
           f->get_member_function_templates().end(),
           s->get_member_function_templates().begin(),
           s->get_member_function_templates().end(),
           changes->member_fn_tmpls_changes());
 
  <