diff --git a/libstdc++-v3/ChangeLog b/libstdc++-v3/ChangeLog
index e2197bad5be6..4611906d75d1 100644
--- a/libstdc++-v3/ChangeLog
+++ b/libstdc++-v3/ChangeLog
@@ -1,3 +1,8 @@
+2006-03-28  Paolo Carlini  <pcarlini@suse.de>
+
+	* include/ext/vstring.h (operator[]): Allow s[s.size()] in
+	debug mode, but not pedantic mode.
+
 2006-03-24  Mark Mitchell  <mark@codesourcery.com>
             Joseph S. Myers  <joseph@codesourcery.com>
 
diff --git a/libstdc++-v3/include/ext/vstring.h b/libstdc++-v3/include/ext/vstring.h
index a117c5826eeb..5cd84b15a307 100644
--- a/libstdc++-v3/include/ext/vstring.h
+++ b/libstdc++-v3/include/ext/vstring.h
@@ -449,7 +449,10 @@ _GLIBCXX_BEGIN_NAMESPACE(__gnu_cxx)
       reference
       operator[](size_type __pos)
       {
-	_GLIBCXX_DEBUG_ASSERT(__pos < this->size());
+        // allow pos == size() as v3 extension:
+	_GLIBCXX_DEBUG_ASSERT(__pos <= this->size());
+        // but be strict in pedantic mode:
+	_GLIBCXX_DEBUG_PEDASSERT(__pos < this->size());
 	this->_M_leak();
 	return this->_M_data()[__pos];
       }