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        Mon, 17 Jun 2019 09:34:14 -0700 (PDT)
Subject: Re: malloc() returns pointer to already allocated memory
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Date: Mon, 17 Jun 2019 18:33:09 +0200
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On 2019-06-17 09:27, Rod Pemberton wrote:
> The program seems to make a large number (on my machine) of small
> allocations around ~268M (~0x0ff5d000) before a "clobber".  CWSDPR0
> aborts with an error about page tables.  Could CWSDPMI be running out
> of page tables? ...  Also, IIRC, PMODETSR doesn't use paging, and it
> completes without any "clobbers".  The large number of allocation might
> also be why no one noticed, or maybe this was a known issue in the past
> but forgotten?

The test program also works okay on hdpmi32, which doesn't use paging 
either. In the program I'm working on, this clobbering does happen with 
hdpmi, and almost immediately on startup too, after allocating maybe 4MB 
or so. Hence why I'm not sure if this initial issue is related. Still 
I've traced the clobbering pointer down and it does seem to come 
straight from malloc.