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From: Don Lewis <Don.Lewis@tsc.tdk.com>
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Date: Fri, 19 Sep 1997 04:32:37 -0700
In-Reply-To: Darryl Okahata <darrylo@mina.sr.hp.com>
       "Re: Bug in malloc/free (was: Memory leak in getservbyXXX?)" (Sep 18,  5:13pm)
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To: darrylo@sr.hp.com, "Jordan K. Hubbard" <jkh@time.cdrom.com>
Subject: Re: Bug in malloc/free (was: Memory leak in getservbyXXX?)
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On Sep 18,  5:13pm, Darryl Okahata wrote:
} Subject: Re: Bug in malloc/free (was: Memory leak in getservbyXXX?)
} > Man, I sure wish there was a copy of purify available for FreeBSD.
} > It's great at catching stuff like this! :(
} 
}      Yeah, me too.  Purify may be "black magic", but it's incredible at
} how well it works.
} 
}      Anyway, if anyone has copious amounts of free time, they might want
} to port "checker", a vaguely purify-like memory checker for
} Linux/Solaris.  It works by using a special patched version of GNU as
} and runtime libraries.

I've had very good luck with the bounds checker patches to gcc.  You
can find it at URL: <ftp://dse.doc.ic.ac.uk/pub/misc/bcc>.  It's very
good at finding the exact location of bugs like array overruns,
incrementing pointers past the end of objects, attempting to access
freed memory, etc.  It's two big weaknesses are the inability to
check signal handlers, and a vast appetite for CPU cycles.  I've typically
seen CPU usage increase by a factor of 10 to 20.

			---  Truck