Re: malloc + 4??

From: Keith Thompson (kst-u_at_mib.org)
Date: 04/05/04 

Date: Mon, 05 Apr 2004 09:30:12 GMT

"Kevin Torr" <kevintorr@hotmail.com> writes:
> "Chris Torek" <nospam@torek.net> wrote in message
> news:c4pdra031ga@news2.newsguy.com...
[...]
> Wow, thanks for all that. I will have to get my head around it all.
>
> So when do I need not cast mallocs? when I include a header? which header?
> Or are you saying that I don't need to cast a malloc if I've already defined
> the pointer as a data type?
> What would be a possible bad thing if I did cast a malloc when I didn't need
> to? Is there something that could go wrong or is it just redundant?

Speaking of redundant, you just re-posted over 230 lines of Chris
Torek's text. Please limit quoted material to what's relevant to your
reply.

To answer your question, if you're going to use malloc() you should
always include <stdlib.h>, and you should never cast the result.

Casting the result masks possible errors. It can eliminate the
warning message you'll get if you've forgotten to include <stdlib.h>,
but only because you're lying to the compiler. It's like eliminating
a warning light on your dashboard by unscrewing the light bulb rather
than by fixing the problem it's trying to tell you about. 

-- 
Keith Thompson (The_Other_Keith) kst-u@mib.org  <http://www.ghoti.net/~kst>
San Diego Supercomputer Center             <*>  <http://users.sdsc.edu/~kst>
Schroedinger does Shakespeare: "To be *and* not to be"

Relevant Pages

  • Re: problem with memcpy and pointers/arrays confusion - again
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  • Re: why is casting malloc a bad thing?
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    (comp.lang.c)
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    (comp.lang.c)
  • Re: Using malloc
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    (alt.comp.lang.learn.c-cpp)