From:	"Edmund Horner" <ejrh AT paradise DOT net DOT nz>
Newsgroups:	comp.os.msdos.djgpp
References:	<8q1u4s$jh3$1 AT info DOT cyf-kr DOT edu DOT pl>
Subject:	Re: deleting NULL ?
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Date:	Sun, 17 Sep 2000 21:30:18 +1200
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To:	djgpp AT delorie DOT com
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Reply-To:	djgpp AT delorie DOT com

Freeing (or deleting, in C++) the NULL pointer is not supposed to be done!
Some DPMI servers ignore it, and some (such as DJGPP) will cause a SIGSEGV
(segment violation) -- you're program will crash, and this is what you want
to happen!

If you ever try to free NULL, then you know you've got something wrong.

In other words, yes, you should always check first to see if you have
allocated something in the first place.  I do not know what happens when you
try to call a method (such as a destructor) from an object at location NULL.
But you already know that you can never have a valid object at NULL in the
first place!

"Rafał Maj" <r_maj AT poczta DOT onet DOT pl> wrote in message
news:8q1u4s$jh3$1 AT info DOT cyf-kr DOT edu DOT pl...
> Hi,
> what is supposed to happen when I'll try delete NULL:
> int* x = NULL;
> delete x;
> Should I every time write   if (x) delete x;    ?
>
> And what about :
> int* x=NULL;
> delete []x;
>
> What will happen when I'll use my class, witch have destructor ?
> myclass* x=NULL;
> delete x;
> delete []x;
>
> Will all above examples work same for other compilers then DJGPP ?
>
> Thanks, Rafal
>
>
>

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