Re: [PATCH] Use NULL instead of integer 0 in security/selinux/

[Alexandre Oliva]

On Jul 10, 2004, Eyal Lebedinsky <eyal@xxxxxxxxxxxxxx> wrote:

> Very much yes. I will go further and say that only boolean
> variables should use the above syntax. Using
> 	if (i)
> where 'i' is a non-boolean integer instead of
> 	if (0 != i)
> makes me question what the programmer wanted. Since integers
> do not have clear names for true/false logic (booleans usually
> will be called something like 'have_brain" etc.) the simple
> 'if (i)' may just as well be a miswritten 'if (!i)' - and I
> caught a few of these bugs in my time.

So how about pushing for writing (i == 1) if i is boolean, to be
clearer?  It's often nice to be able to tell whether a boolean
variable is strict 0/1 or just zero/non-zero, when you're thinking of
switching to 3+-state logic.  But guess what, i == 1 is far less
efficient than i != 0 on many architectures.  It's an unfortunate
trade-off you have to make in this case.

-- 
Alexandre Oliva             http://www.ic.unicamp.br/~oliva/
Red Hat Compiler Engineer   aoliva@{redhat.com, gcc.gnu.org}
Free Software Evangelist  oliva@{lsd.ic.unicamp.br, gnu.org}
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