Index: string
===================================================================
--- string	(revision 611869)
+++ string	(working copy)
@@ -266,7 +266,12 @@
     void reserve (size_type = 0);
 
     void clear () {
-        _C_unlink (_C_nullref ()->data ());
+        if (size_type (1) < size_type (_C_pref ()->_C_get_ref ()))
+            _C_unlink (_C_nullref ()->data ());
+        else {
+	        traits_type::assign (_C_data [0], value_type ());
+            _C_pref ()->_C_size._C_size = 0;
+        }
     }
 
     bool empty () const  {
Index: string.cc
===================================================================
--- string.cc	(revision 611869)
+++ string.cc	(working copy)
@@ -374,7 +374,7 @@
     }
     else {
         // special case a substitution that leaves the string empty.
-        _C_unlink (_C_nullref ()->data ());
+        clear ();
     }
 
     return *this;
@@ -447,8 +447,8 @@
         }
     }
     else {
-        // construct the empty string
-        _C_unlink (_C_nullref ()->data ());
+        // special case a substitution that leaves the string empty.
+        clear ();
     }
 
     return *this;
Index: istream.cc
===================================================================
--- istream.cc	(revision 611869)
+++ istream.cc	(working copy)
@@ -877,7 +877,7 @@
 
     if (__ipfx) { 
 
-        __str.erase ();
+        __str.clear ();
 
         // carefuly handle arithmetic overflow
         _SizeT __n = __str.max_size ();