Date: Wed, 23 Aug 2000 09:08:30 +0200
From: "Eli Zaretskii" <eliz AT is DOT elta DOT co DOT il>
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To: munin AT munin DOT inka DOT de
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In-reply-to: <r1j5qsg8vjruoq5s3q515lq33fcrmi1vur@4ax.com> (message from Bernd
	Becker on Wed, 23 Aug 2000 01:23:15 +0100)
Subject: Re: freeing/allocating memory causes a SIGSEGV
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> From: Bernd Becker <munin AT munin DOT inka DOT de>
> Newsgroups: comp.os.msdos.djgpp
> Date: Wed, 23 Aug 2000 01:23:15 +0100
> 
> When memory is allocated/freed in a loop the program will crash after
> going through it for a while with a SIGSEGV.

Crashes in malloc or free usually mean that your program writes past
the end of allocated buffers, and thus overwrites the hidden info
stored just before and just after the allocated space, where
malloc/free keep the information about allocated memory.

I suggest to examine closely your code, and look for places which
might do that.  Using YAMD or another malloc debugger might also help
(YAMD is not effective unless you run it on plain DOS, though).

See section 9.2 of the DJGPP FAQ list for more about this.