Re: [Sheflug] Re: [Sheflug - Sheffield Linux User's Group] Re: Segfaults & ld.so wierditude

[Al Hudson <nospam [at] york.ac.uk>]

On Tue, 2 May 2000, Bob Ham wrote:

> > Sounds to me like you've got a bogus pointer somewhere that's
> > overwriting malloc's private data.
> 
> It's that malloc() itself segfaults, as in in the backtrace I get
> strdup(), malloc(), malloc() right at the top.

Not wanting to go over ground others have covered, but yes, doing dodgy
things with malloc()'d memory, you would expect it to crash in malloc().
Actually, these can be the worst bugs to try and trace - doing a double
free(), for example, has rightly been noted as screwing up the malloc()
internals. However, you may not find that out for a while - it's not
necessarily the case that the next time you call malloc() it'll go belly
up; I think the best way of describing it is 'operation not defined' ;)

> > Have you tried Electric Fence and cousins?
> 
> Never heard of it; care to expand on that?

I use efence, highly recommended.

Cheers,

Alex.

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