diff --git a/libstdc++-v3/ChangeLog b/libstdc++-v3/ChangeLog
index 6cedb5e8ddd..6e28250af19 100644
--- a/libstdc++-v3/ChangeLog
+++ b/libstdc++-v3/ChangeLog
@@ -1,3 +1,16 @@
+2005-12-10  Paolo Carlini  <pcarlini@suse.de>
+
+	* include/ext/sso_string_base.h (__sso_string_base<>::_M_compare):
+	Add, specialized for char and wchar_t to immediately return true
+	when a string is compared to itself.
+	* include/ext/rc_string_base.h (__rc_string_base<>::_M_compare):
+	Likewise, for the same _Rep.
+	* include/ext/vstring.h (compare(const string&)): Use it.
+
+	* include/ext/sso_string_base.h (__sso_string_base<>::_M_destroy):
+	Deallocate passed size + 1.
+	(_M_dispose, _M_reserve): Adjust.
+
 2005-12-09  Paolo Carlini  <pcarlini@suse.de>
 	    Howard Hinnant  <hhinnant@apple.com>
 
diff --git a/libstdc++-v3/include/ext/rc_string_base.h b/libstdc++-v3/include/ext/rc_string_base.h
index 9636a813a02..43a69c2c1b6 100644
--- a/libstdc++-v3/include/ext/rc_string_base.h
+++ b/libstdc++-v3/include/ext/rc_string_base.h
@@ -334,6 +334,10 @@ namespace __gnu_cxx
       
       void
       _M_erase(size_type __pos, size_type __n);
+
+      bool
+      _M_compare(const __rc_string_base&) const
+      { return false; }
     };
 
   template<typename _CharT, typename _Traits, typename _Alloc>
@@ -670,6 +674,28 @@ namespace __gnu_cxx
 
       _M_rep()->_M_set_length(__new_size);      
     }
+
+  template<>
+    inline bool
+    __rc_string_base<char, std::char_traits<char>,
+		     std::allocator<char> >::
+    _M_compare(const __rc_string_base& __rcs) const
+    {
+      if (_M_rep() == __rcs._M_rep())
+	return true;
+      return false;
+    }
+
+  template<>
+    inline bool
+    __rc_string_base<wchar_t, std::char_traits<wchar_t>,
+		     std::allocator<wchar_t> >::
+    _M_compare(const __rc_string_base& __rcs) const
+    {
+      if (_M_rep() == __rcs._M_rep())
+	return true;
+      return false;
+    }
 } // namespace __gnu_cxx
 
 #endif /* _RC_STRING_BASE_H */
diff --git a/libstdc++-v3/include/ext/sso_string_base.h b/libstdc++-v3/include/ext/sso_string_base.h
index 1b967b98283..bb0d746eca5 100644
--- a/libstdc++-v3/include/ext/sso_string_base.h
+++ b/libstdc++-v3/include/ext/sso_string_base.h
@@ -102,7 +102,7 @@ namespace __gnu_cxx
       _M_dispose()
       {
 	if (!_M_is_local())
-	  _M_destroy(_M_allocated_capacity + 1);
+	  _M_destroy(_M_allocated_capacity);
       }
 
       void
@@ -225,13 +225,17 @@ namespace __gnu_cxx
 
       void
       _M_erase(size_type __pos, size_type __n);
+
+      bool
+      _M_compare(const __sso_string_base&) const
+      { return false; }
     };
 
   template<typename _CharT, typename _Traits, typename _Alloc>
     void
     __sso_string_base<_CharT, _Traits, _Alloc>::
     _M_destroy(size_type __size) throw()
-    { _CharT_alloc_type(_M_get_allocator()).deallocate(_M_data(), __size); }
+    { _CharT_alloc_type(_M_get_allocator()).deallocate(_M_data(), __size + 1); }
 
   template<typename _CharT, typename _Traits, typename _Alloc>
     void
@@ -498,7 +502,7 @@ namespace __gnu_cxx
 	  else if (!_M_is_local())
 	    {
 	      _S_copy(_M_local_data, _M_data(), _M_length() + 1);
-	      _M_destroy(__capacity + 1);
+	      _M_destroy(__capacity);
 	      _M_data(_M_local_data);
 	    }
 	}
@@ -541,6 +545,28 @@ namespace __gnu_cxx
 
       _M_set_length(_M_length() - __n);
     }
+
+  template<>
+    inline bool
+    __sso_string_base<char, std::char_traits<char>,
+		      std::allocator<char> >::
+    _M_compare(const __sso_string_base& __rcs) const
+    {
+      if (this == &__rcs)
+	return true;
+      return false;
+    }
+
+  template<>
+    inline bool
+    __sso_string_base<wchar_t, std::char_traits<wchar_t>,
+		      std::allocator<wchar_t> >::
+    _M_compare(const __sso_string_base& __rcs) const
+    {
+      if (this == &__rcs)
+	return true;
+      return false;
+    }
 } // namespace __gnu_cxx
 
 #endif /* _SSO_STRING_BASE_H */
diff --git a/libstdc++-v3/include/ext/vstring.h b/libstdc++-v3/include/ext/vstring.h
index 4a5228518d7..1c59e717915 100644
--- a/libstdc++-v3/include/ext/vstring.h
+++ b/libstdc++-v3/include/ext/vstring.h
@@ -1665,6 +1665,9 @@ namespace __gnu_cxx
       int
       compare(const __versa_string& __str) const
       {
+	if (this->_M_compare(__str))
+	  return 0;
+
 	const size_type __size = this->size();
 	const size_type __osize = __str.size();
 	const size_type __len = std::min(__size, __osize);