re PR libstdc++/16611 (Terrible code generated for vector<bool>)

2006-08-06  Paolo Carlini  <pcarlini@suse.de>

	PR libstdc++/16611
	* include/bits/stl_bvector.h (vector<bool>::operator[],
	vector<bool>::operator[] const): Do not use iterator::operator+,
	hand code.

From-SVN: r115972

libstdc++-v3/ChangeLog

+2006-08-06  Paolo Carlini  <pcarlini@suse.de>
+
+	PR libstdc++/16611
+	* include/bits/stl_bvector.h (vector<bool>::operator[],
+	vector<bool>::operator[] const): Do not use iterator::operator+,
+	hand code.
+
 2006-08-05  Paolo Carlini  <pcarlini@suse.de>
 
 	PR libstdc++/28587

libstdc++-v3/include/bits/stl_bvector.h

@@ -575,11 +575,17 @@ template<typename _Alloc>
 
     reference
     operator[](size_type __n)
-    { return *(begin() + difference_type(__n)); }
+    {
+      return *iterator(this->_M_impl._M_start._M_p
+		       + __n / int(_S_word_bit), __n % int(_S_word_bit));
+    }
 
     const_reference
     operator[](size_type __n) const
-    { return *(begin() + difference_type(__n)); }
+    {
+      return *const_iterator(this->_M_impl._M_start._M_p
+			     + __n / int(_S_word_bit), __n % int(_S_word_bit));
+    }
 
   protected:
     void