patch for ext/debug_allocator.h (second attempt)

[Dhruv Matani <dhruvbird at gmx dot net>]

This patch makes the debug_allocator<> compile now. Earlier, the
debug_allocator<> had code like this:

size_type n;
pointer x;
*x = n;

Which made no sense.





-- 
	-Dhruv Matani.
http://www.geocities.com/dhruvbird/

Attachment: changelog_debug_alloc
Description: Text document

*** debug_allocator.h_old	Tue Feb  3 21:47:11 2004
--- debug_allocator.h	Tue Feb  3 22:58:42 2004
***************
*** 48,54 ****
  #ifndef _DEBUG_ALLOCATOR_H
  #define _DEBUG_ALLOCATOR_H 1
  
! #include <memory>
  
  namespace __gnu_cxx
  {
--- 48,54 ----
  #ifndef _DEBUG_ALLOCATOR_H
  #define _DEBUG_ALLOCATOR_H 1
  
! #include <cstdlib>
  
  namespace __gnu_cxx
  {
*************** namespace __gnu_cxx
*** 74,103 ****
        typedef typename _Alloc::value_type       value_type;
  
      private:
!       // Size of space used to store size.  Note that this must be
!       // large enough to preserve alignment.
!       const size_t 		_M_extra;
        
        _Alloc			_M_allocator;
  
      public:
!       debug_allocator() : _M_extra(8) { }
  
        pointer
!       allocate(size_type __n, std::allocator<void>::const_pointer = 0)
        {
!         pointer __result = _M_allocator.allocate(__n + _M_extra);
          *__result = __n;
!         return __result + _M_extra;
        }
  
        void
        deallocate(pointer __p, size_type __n)
        {
!         pointer __real_p = __p - _M_extra;
          if (*__real_p != __n)
            abort();
!         _M_allocator.deallocate(__real_p, __n + _M_extra);
        }
      };
  } // namespace __gnu_cxx
--- 74,117 ----
        typedef typename _Alloc::value_type       value_type;
  
      private:
!       //  _M_extra is the number of objects that the extra space
!       //  corresponds to.
!       const size_type 		_M_extra;
        
        _Alloc			_M_allocator;
  
+       static size_type _S_num_objects (size_t _Extra_size, size_t _Obj_size)
+       {
+ 	return (_Extra_size + _Obj_size - 1) / _Obj_size;
+       }
+       
      public:
!       debug_allocator() : _M_extra(_S_num_objects(8, sizeof(value_type))) { }
!       
!       pointer
!       allocate(size_type __n)
!       {
!         size_type *__result = reinterpret_cast<size_type*>(_M_allocator.allocate(__n + _M_extra));
!         *__result = __n;
!         return reinterpret_cast<pointer>(__result) + _M_extra;
!       }
  
        pointer
!       allocate(size_type __n, const void *__hint)
        {
!         size_type *__result = reinterpret_cast<size_type*>(_M_allocator.allocate(__n + _M_extra, 
! 										 __hint));
          *__result = __n;
!         return reinterpret_cast<pointer>(__result) + _M_extra;
        }
  
        void
        deallocate(pointer __p, size_type __n)
        {
!         size_type *__real_p = __p - _M_extra;
          if (*__real_p != __n)
            abort();
!         _M_allocator.deallocate(reinterpret_cast<pointer>(__real_p), __n + _M_extra);
        }
      };
  } // namespace __gnu_cxx