Path: utzoo!utgpu!cunews!bnrgate!brtph3!brchh104!brchs1!bnr.ca!rice.edu!sun-spots-request
From: henry@zoo.toronto.edu (Henry Spencer)
Newsgroups: comp.sys.sun
Subject: Re: Segment violation from malloc (what does it mean?)
Keywords: Miscellaneous
Message-ID: <1095@brchh104.bnr.ca>
Date: 7 Jan 91 17:50:56 GMT
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Organization: Sun-Spots
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In article <1063@brchh104.bnr.ca> fredc@umrisca.isc.umr.edu writes:
>I have been working on a big SunView program for a while now, and, after
>adding some [more] dynamically allocated data structures which endure for
>the entire program, dbxtool gave me the following message:
>
>signal SEGV (no mapping at the fault address) in malloc at 0xec52864

A segmentation violation in malloc almost invariably means that you have
corrupted its data structures.  Ways of doing this include, depending on
circumstances and system variant:  freeing something that was not
malloced, freeing NULL, freeing something twice, writing past the end (or
beginning) of a malloced area, writing into an area that was malloced but
has been freed, and writing into memory at random (typically due to
garbaged pointers or grossly out-of-bounds array subscripts).

>What I want to know is: does this message mean I am running into a limit
>on my dynamic storage space? ...

Almost certainly not.  That should just give you a NULL return value.  A
program bug is much more likely.

If the Space Shuttle was the answer,   | Henry Spencer at U of Toronto Zoology
what was the question?                 |  henry@zoo.toronto.edu   utzoo!henry