Re: [jason@txt.com: Re: Problem with "chars"]

[Marius Nita <marius@cs.pdx.edu>]

On Wed, Jul 17, 2002 at 10:55:52AM -0700, Jason P. Winters wrote:
>  
> > On Wed, Jul 17, 2002 at 09:33:16AM -0500, xlp wrote:
> > > char *foo()
> > > {
> > > 	char *retbar;
> > > 	retbar = (char *)malloc(20);
> > 
> > Although it's tend to be an aesthitic issue, it is a *good* habit to not
> > cast malloc().  
> 
> Huh?  I mean, excuse me?  Where do you find a reference to _not_ casting
> the output of malloc()?   Malloc returns a (void *) reference, you -need-
> to cast it to the type you're assigning it as.

The other folks already answered this, but it's worth pointing out that W
Richard Stevens talks about this in Advanced Programming in the Unix
Environment, and points out that the return of malloc should NOT be casted,
and stdlib.h should be included to avoid warnings..

It seems that this issue has become a religious thing, tho I don't see why. It
is clear that the return of malloc need not (and must not--for correctness) be
casted.

Besides,

  struct Blah *foo = malloc( sizeof(struct Blah) );

looks a lot more readable than

  struct Blah *foo = (struct Blah *)malloc( sizeof(struct Blah) );

> If you don't cast it, you get a warning message:
> 
> tst.c: In function `foo':
> tst.c:17: warning: assignment makes pointer from integer without a cast
> 
> 
> So, do we ignore the message from the compiler? 
> 
> Now, *That's* a bad habit to get into...
> 
> Ciao!
> 
> Jason
> -- 
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