FIX: Access violation when you use the Realloc function in a small memory block in Visual C++ 6.0

1. In the following code block in the Realloc.c file:

   //  if the new size is not over __sbh_threshold, attempt
   //  to reallocate within the small-block heap
   if (newsize <= __sbh_threshold)
   {
      if (__sbh_resize_block(pHeader, pBlock, newsize))
         pvReturn = pBlock;
      else if ((pvReturn = __sbh_alloc_block(newsize)) != NULL)
      {
         oldsize = ((PENTRY)((char *)pBlock -
                            sizeof(int)))->sizeFront - 1;
         memcpy(pvReturn, pBlock, __min(oldsize, newsize));
         __sbh_free_block(pHeader, pBlock);
      }
   }
   						

   Replace this line of code:

   __sbh_free_block(pHeader, pBlock);

   with this:

   pHeader = __sbh_find_block(pBlock);
   __sbh_free_block(pHeader, pBlock);

   And rebuild CRT. NOTE: If you are rebuilding the DLL version of CRT, then the new DLL name should not start with "msvc".
2. Implement your own Realloc() function to avoid using the CRT implementation.
3. Use the _set_sbh_threshold(0) function to avoid the use of the small block heap. Both Windows NT 4.0 SP4 and Windows 2000 have an efficient OS-level heap implementation. You may encounter performance problems on Windows 95 and Windows 98 because its operating system heap implementation is not as efficient as the one on Windows NT.

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Steps to Reproduce Behavior

//main.cpp

#include "stdio.h"
#include "stdlib.h"

int main()
{
	char* pData;

	for( int i=0; i< 70000; i++ )
	{
            pData = (char*)malloc( 32 );
            pData = (char*)realloc( pData, 290 );  //access violation in small-block allocator 
	}	

	return(0);
} //end main
				

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