* include/backward/hashtable.h (erase): Correctly handle erasing a

	reference to an entry in the hash table.
	* testsuite/backward/hash_map/25896.cc: New.
	* testsuite/backward/hash_set/25896.cc: New.


git-svn-id: svn+ssh://gcc.gnu.org/svn/gcc/trunk@145788 138bc75d-0d04-0410-961f-82ee72b054a4

4 files changed, 352 insertions, 6 deletions

diff --git a/libstdc++-v3/ChangeLog b/libstdc++-v3/ChangeLog
index f51807b76d6..831de204fb4 100644
--- a/libstdc++-v3/ChangeLog
+++ b/libstdc++-v3/ChangeLog
@@ -1,3 +1,10 @@
+2009-04-08  Ian Lance Taylor  <iant@google.com>
+
+	* include/backward/hashtable.h (erase): Correctly handle erasing a
+	reference to an entry in the hash table.
+	* testsuite/backward/hash_map/25896.cc: New.
+	* testsuite/backward/hash_set/25896.cc: New.
+
 2009-04-08  Adam Nemet  <anemet@caviumnetworks.com>
 
 	* config/abi/post/mips64-linux-gnu/baseline_symbols.txt:
diff --git a/libstdc++-v3/include/backward/hashtable.h b/libstdc++-v3/include/backward/hashtable.h
index e0ba83b34f1..cfa6f06a913 100644
--- a/libstdc++-v3/include/backward/hashtable.h
+++ b/libstdc++-v3/include/backward/hashtable.h
@@ -869,8 +869,9 @@ _GLIBCXX_BEGIN_NAMESPACE(__gnu_cxx)
     {
       const size_type __n = _M_bkt_num_key(__key);
       _Node* __first = _M_buckets[__n];
+      _Node* __saved_slot = 0;
       size_type __erased = 0;
-      
+
       if (__first)
 	{
 	  _Node* __cur = __first;
@@ -879,11 +880,20 @@ _GLIBCXX_BEGIN_NAMESPACE(__gnu_cxx)
 	    {
 	      if (_M_equals(_M_get_key(__next->_M_val), __key))
 		{
-		  __cur->_M_next = __next->_M_next;
-		  _M_delete_node(__next);
-		  __next = __cur->_M_next;
-		  ++__erased;
-		  --_M_num_elements;
+		  if (&_M_get_key(__next->_M_val) != &__key)
+		    {
+		      __cur->_M_next = __next->_M_next;
+		      _M_delete_node(__next);
+		      __next = __cur->_M_next;
+		      ++__erased;
+		      --_M_num_elements;
+		    }
+		  else
+		    {
+		      __saved_slot = __cur;
+		      __cur = __next;
+		      __next = __cur->_M_next;
+		    }
 		}
 	      else
 		{
@@ -898,6 +908,14 @@ _GLIBCXX_BEGIN_NAMESPACE(__gnu_cxx)
 	      ++__erased;
 	      --_M_num_elements;
 	    }
+	  if (__saved_slot)
+	    {
+	      __next = __saved_slot->_M_next;
+	      __saved_slot->_M_next = __next->_M_next;
+	      _M_delete_node(__next);
+	      ++__erased;
+	      --_M_num_elements;
+	    }
 	}
       return __erased;
     }
diff --git a/libstdc++-v3/testsuite/backward/hash_map/25896.cc b/libstdc++-v3/testsuite/backward/hash_map/25896.cc
new file mode 100644
index 00000000000..e7d1f84837d
--- /dev/null
+++ b/libstdc++-v3/testsuite/backward/hash_map/25896.cc
@@ -0,0 +1,161 @@
+// { dg-options "-Wno-deprecated" }
+
+// Copyright (C) 2009 Free Software Foundation, Inc.
+//
+// This file is part of the GNU ISO C++ Library.  This library is free
+// software; you can redistribute it and/or modify it under the
+// terms of the GNU General Public License as published by the
+// Free Software Foundation; either version 2, or (at your option)
+// any later version.
+//
+// This library is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+//
+// You should have received a copy of the GNU General Public License along
+// with this library; see the file COPYING.  If not, write to the Free
+// Software Foundation, 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301,
+// USA.
+
+// This is a copy of tr1/6_containers/unordered_map/erase/1.cc, using
+// hash_map instead of unordered_map.
+
+#include <hash_map>
+#include <string>
+#include <testsuite_hooks.h>
+
+namespace __gnu_cxx
+{
+  using std::string;
+
+  inline size_t hash_string(const char* s)
+  {
+    unsigned long h;
+    for (h=0; *s; ++s) {
+      h = 5*h + *s;
+    }
+    return size_t(h);
+  }
+
+  template<class T> struct hash<T *>
+  {
+    size_t operator()(const T *const & s) const
+      { return reinterpret_cast<size_t>(s); }
+  };
+
+  template<> struct hash<string>
+  {
+    size_t operator()(const string &s) const { return hash_string(s.c_str()); }
+  };
+
+  template<> struct hash<const string>
+  {
+    size_t operator()(const string &s) const { return hash_string(s.c_str()); }
+  };
+}
+
+void test01()
+{
+  bool test __attribute__((unused)) = true;
+
+  typedef __gnu_cxx::hash_map<std::string, int> Map;
+  typedef Map::iterator       iterator;
+  typedef Map::const_iterator const_iterator;
+  typedef Map::value_type     value_type;
+
+  Map m1;
+
+  m1.insert(value_type("because to why", 1));
+  m1.insert(value_type("the stockholm syndrome", 2));
+  m1.insert(value_type("a cereous night", 3));
+  m1.insert(value_type("eeilo", 4));
+  m1.insert(value_type("protean", 5));
+  m1.insert(value_type("the way you are when", 6));
+  m1.insert(value_type("tillsammans", 7));
+  m1.insert(value_type("umbra/penumbra", 8));
+  m1.insert(value_type("belonging (no longer mix)", 9));
+  m1.insert(value_type("one line behind", 10));
+  VERIFY( m1.size() == 10 );
+
+  VERIFY( m1.erase("eeilo") == 1 );
+  VERIFY( m1.size() == 9 );
+  iterator it1 = m1.find("eeilo");
+  VERIFY( it1 == m1.end() );
+
+  VERIFY( m1.erase("tillsammans") == 1 );
+  VERIFY( m1.size() == 8 );
+  iterator it2 = m1.find("tillsammans");
+  VERIFY( it2 == m1.end() );
+
+  // Must work (see DR 526)
+  iterator it3 = m1.find("belonging (no longer mix)");
+  VERIFY( it3 != m1.end() );
+  VERIFY( m1.erase(it3->first) == 1 );
+  VERIFY( m1.size() == 7 );
+  it3 = m1.find("belonging (no longer mix)");
+  VERIFY( it3 == m1.end() );
+
+  VERIFY( !m1.erase("abra") );
+  VERIFY( m1.size() == 7 );
+
+  VERIFY( !m1.erase("eeilo") );
+  VERIFY( m1.size() == 7 );
+
+  VERIFY( m1.erase("because to why") == 1 );
+  VERIFY( m1.size() == 6 );
+  iterator it4 = m1.find("because to why");
+  VERIFY( it4 == m1.end() );
+
+  iterator it5 = m1.find("umbra/penumbra");
+  iterator it6 = m1.find("one line behind");
+  VERIFY( it5 != m1.end() );
+  VERIFY( it6 != m1.end() );
+
+  VERIFY( m1.find("the stockholm syndrome") != m1.end() );
+  VERIFY( m1.find("a cereous night") != m1.end() );
+  VERIFY( m1.find("the way you are when") != m1.end() );
+  VERIFY( m1.find("a cereous night") != m1.end() );
+
+  VERIFY( m1.erase(it5->first) == 1 );
+  VERIFY( m1.size() == 5 );
+  it5 = m1.find("umbra/penumbra");
+  VERIFY( it5 == m1.end() );
+
+  VERIFY( m1.erase(it6->first) == 1 );
+  VERIFY( m1.size() == 4 );
+  it6 = m1.find("one line behind");
+  VERIFY( it6 == m1.end() );
+
+  iterator it7 = m1.begin();
+  iterator it8 = it7;
+  ++it8;
+  iterator it9 = it8;
+  ++it9;
+
+  VERIFY( m1.erase(it8->first) == 1 );
+  VERIFY( m1.size() == 3 );
+  VERIFY( ++it7 == it9 );
+
+  iterator it10 = it9;
+  ++it10;
+  iterator it11 = it10;
+
+  VERIFY( m1.erase(it9->first) == 1 );
+  VERIFY( m1.size() == 2 );
+  VERIFY( ++it10 == m1.end() );
+
+  m1.erase(m1.begin());
+  VERIFY( m1.size() == 1 );
+  VERIFY( m1.begin() == it11 );
+
+  VERIFY( m1.erase(m1.begin()->first) == 1 );
+  VERIFY( m1.size() == 0 );
+  VERIFY( m1.begin() == m1.end() );
+}
+
+int main()
+{
+  test01();
+  return 0;
+}
diff --git a/libstdc++-v3/testsuite/backward/hash_set/25896.cc b/libstdc++-v3/testsuite/backward/hash_set/25896.cc
new file mode 100644
index 00000000000..9baa6f1f7d6
--- /dev/null
+++ b/libstdc++-v3/testsuite/backward/hash_set/25896.cc
@@ -0,0 +1,160 @@
+// { dg-options "-Wno-deprecated" }
+//
+// Copyright (C) 2009 Free Software Foundation, Inc.
+//
+// This file is part of the GNU ISO C++ Library.  This library is free
+// software; you can redistribute it and/or modify it under the
+// terms of the GNU General Public License as published by the
+// Free Software Foundation; either version 2, or (at your option)
+// any later version.
+//
+// This library is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+//
+// You should have received a copy of the GNU General Public License along
+// with this library; see the file COPYING.  If not, write to the Free
+// Software Foundation, 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301,
+// USA.
+
+// This is a copy of tr1/6_containers/unordered_set/erase/1.cc, using
+// hash_set instead of unordered_set.
+
+#include <hash_set>
+#include <string>
+#include <testsuite_hooks.h>
+
+namespace __gnu_cxx
+{
+  using std::string;
+
+  inline size_t hash_string(const char* s)
+  {
+    unsigned long h;
+    for (h=0; *s; ++s) {
+      h = 5*h + *s;
+    }
+    return size_t(h);
+  }
+
+  template<class T> struct hash<T *>
+  {
+    size_t operator()(const T *const & s) const
+      { return reinterpret_cast<size_t>(s); }
+  };
+
+  template<> struct hash<string>
+  {
+    size_t operator()(const string &s) const { return hash_string(s.c_str()); }
+  };
+
+  template<> struct hash<const string>
+  {
+    size_t operator()(const string &s) const { return hash_string(s.c_str()); }
+  };
+}
+
+void test01()
+{
+  bool test __attribute__((unused)) = true;
+
+  typedef __gnu_cxx::hash_set<std::string> Set;
+  typedef Set::iterator       iterator;
+  typedef Set::const_iterator const_iterator;
+
+  Set s1;
+
+  s1.insert("because to why");
+  s1.insert("the stockholm syndrome");
+  s1.insert("a cereous night");
+  s1.insert("eeilo");
+  s1.insert("protean");
+  s1.insert("the way you are when");
+  s1.insert("tillsammans");
+  s1.insert("umbra/penumbra");
+  s1.insert("belonging (no longer mix)");
+  s1.insert("one line behind");
+  VERIFY( s1.size() == 10 );
+
+  VERIFY( s1.erase("eeilo") == 1 );
+  VERIFY( s1.size() == 9 );
+  iterator it1 = s1.find("eeilo");
+  VERIFY( it1 == s1.end() );
+
+  VERIFY( s1.erase("tillsammans") == 1 );
+  VERIFY( s1.size() == 8 );
+  iterator it2 = s1.find("tillsammans");
+  VERIFY( it2 == s1.end() );
+
+  // Must work (see DR 526)
+  iterator it3 = s1.find("belonging (no longer mix)");
+  VERIFY( it3 != s1.end() );
+  VERIFY( s1.erase(*it3) == 1 );
+  VERIFY( s1.size() == 7 );
+  it3 = s1.find("belonging (no longer mix)");
+  VERIFY( it3 == s1.end() );
+
+  VERIFY( !s1.erase("abra") );
+  VERIFY( s1.size() == 7 );
+
+  VERIFY( !s1.erase("eeilo") );
+  VERIFY( s1.size() == 7 );
+
+  VERIFY( s1.erase("because to why") == 1 );
+  VERIFY( s1.size() == 6 );
+  iterator it4 = s1.find("because to why");
+  VERIFY( it4 == s1.end() );
+
+  iterator it5 = s1.find("umbra/penumbra");
+  iterator it6 = s1.find("one line behind");
+  VERIFY( it5 != s1.end() );
+  VERIFY( it6 != s1.end() );
+
+  VERIFY( s1.find("the stockholm syndrome") != s1.end() );
+  VERIFY( s1.find("a cereous night") != s1.end() );
+  VERIFY( s1.find("the way you are when") != s1.end() );
+  VERIFY( s1.find("a cereous night") != s1.end() );
+
+  VERIFY( s1.erase(*it5) == 1 );
+  VERIFY( s1.size() == 5 );
+  it5 = s1.find("umbra/penumbra");
+  VERIFY( it5 == s1.end() );
+
+  VERIFY( s1.erase(*it6) == 1 );
+  VERIFY( s1.size() == 4 );
+  it6 = s1.find("one line behind");
+  VERIFY( it6 == s1.end() );
+
+  iterator it7 = s1.begin();
+  iterator it8 = it7;
+  ++it8;
+  iterator it9 = it8;
+  ++it9;
+
+  VERIFY( s1.erase(*it8) == 1 );
+  VERIFY( s1.size() == 3 );
+  VERIFY( ++it7 == it9 );
+
+  iterator it10 = it9;
+  ++it10;
+  iterator it11 = it10;
+
+  VERIFY( s1.erase(*it9) == 1 );
+  VERIFY( s1.size() == 2 );
+  VERIFY( ++it10 == s1.end() );
+
+  s1.erase(s1.begin());
+  VERIFY( s1.size() == 1 );
+  VERIFY( s1.begin() == it11 );
+
+  VERIFY( s1.erase(*s1.begin()) == 1 );
+  VERIFY( s1.size() == 0 );
+  VERIFY( s1.begin() == s1.end() );
+}
+
+int main()
+{
+  test01();
+  return 0;
+}