Message-ID: <3796A2F9.D273DF@vetec.com>
Date: Wed, 21 Jul 1999 23:50:01 -0500
From: Andy Goth <andygoth AT vetec DOT com>
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To: djgpp AT delorie DOT com
Subject: Re: A Structured Problem ?
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Reply-To: djgpp AT delorie DOT com

> Edward Hill wrote:
> 
> > It's good practice not to cast, malloc doesn't require a cast and a cast
> > can sometimes mask errors.
> 
>     How can casting mask an error?  And why doesn't malloc need a cast?

Casting can mask an error because it defeats type safety.

This is legal:

char* b = "Hello.";
int a = (int)b;

It's probably not a good idea, but the cast lets you get away with it. 
It masks the error.

Malloc doesn't need a cast in C since C doesn't complain about
converting from a void* to any other kind of pointer.  C++ does since it
needs to know what to convert from and will issue a warning if you
convert from void* (besides, you should use "new" in C++, which returns
the specific kind of pointer you want anyway--no void* there).  In C,
the cast is a waste of typing.