Re: How to use Delete in right way

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From: Oleg Starodumov (com-dot-debuginfo-at-oleg)
Date: 01/28/05 

Date: Fri, 28 Jan 2005 11:07:01 +0200

> To be precise, pageheap will also detect this when the block
> is deleted, unless the length of the block is a multiple of 8,
> in which case you should get an access violation at the time of
> corruption.
>
> You can use /unaligned parameter with pageheap to force
> it to always place the block exactly at the end of a page
> but this breaks most non-trivial applications because win32 heap
> is documented to have 8 byte alignment, and many apps depend
> on this.
>

This is true for explicit allocations via HeapAlloc.

If the allocation goes through CRT malloc/new/etc, the CRT's allocation
granularity of 16 bytes hides these problems from PageHeap completely,
unless the length of the block is multiple of 16.

Oleg

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