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From: John Baldwin <jhb@freebsd.org>
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Date: Wed, 5 Jul 2006 12:04:30 -0400
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Cc: Pat Lashley <patl+freebsd@volant.org>,
	Matthias Andree <matthias.andree@gmx.de>,
	Johannes Weiner <hnazfoo@googlemail.com>
Subject: Re: Return value of malloc(0)
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On Saturday 01 July 2006 04:35, Matthias Andree wrote:
> Pat Lashley <patl+freebsd@volant.org> writes:
> 
> > BUT, that said, the safest and most portable coding practice would be:
> >
> >        // The C standard does not require malloc(0) to return NULL;
> >        // but whatever it returns MUST NOT be dereferenced.
> >        ptr = ( size == 0 ) ? NULL : malloc( size ) ;
> 
> Safest (avoiding null derefence) would instead be:
> 
>        ptr = malloc(size ? size : 1);
> 
> BTW: // is not a valid C89 comment, but a GCC-ism.

It's valid in C99 though. :)

-- 
John Baldwin