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Re: alloca is bad?


Chris Faylor wrote:
> 
> On Fri, Nov 10, 2000 at 05:39:29AM -0500, Eli Zaretskii wrote:
> >> Date: Thu, 9 Nov 2000 21:20:32 -0500
> >> From: Christopher Faylor <cgf@redhat.com>
> >>
> >> I was surprised by this assertion and so I thought I'd ask for a
> >> consensus here.  Should the use of alloca be deprecated in gdb?
> >
> >In my experience, there's nothing wrong with alloca as long as it is
> >used for allocating small buffers.  The only consideration is that not
> >every platform supports alloca.
> 
> But, since alloca is already entrenched in gdb and available in liberty
> I don't think this is an issue, is it?
> 

Warning: if the "liberty" alloca() is used a "alloca(0)" must be added to
our interpreter's command loops or the garbage collection becomes somewhat
random (it will only happen when you call alloca() for allocating some
other stuff and will only clean what was allocated by code that executed on frames
below the current stack position.

I think we have this bug when alloca() gets used right now.

(Nothing difficult, we just need to remember to do it)


-- 
Fernando Nasser
Red Hat - Toronto                       E-Mail:  fnasser@redhat.com
2323 Yonge Street, Suite #300
Toronto, Ontario   M4P 2C9

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