Re: PATCH 06/17: compctl: Remove pointless check

[Kamil Dudka <kdudka@redhat.com>]

On Tuesday 06 January 2015 12:09:33 Mikael Magnusson wrote:
> On Tue, Jan 6, 2015 at 10:43 AM, Kamil Dudka <kdudka@redhat.com> wrote:
> > On Monday 05 January 2015 23:53:02 Bart Schaefer wrote:
> >> On Jan 6,  6:25am, Mikael Magnusson wrote:
> >> } Subject: PATCH 06/17: compctl: Remove pointless check
> >> }
> >> } cc has already been derefed a bunch of times leading up to here. Found
> >> } by Coverity (Issue 1255841).
> >> } -    if (cc && cc->xor) {
> >> } +    if (cc->xor) {
> >> 
> >> I'm curious, why bother to "fix" this (and a couple of similar others in
> >> later patches in this series)?  It's not *wrong*, and the change is not
> >> a significant optimization.
> > 
> > True, modern compilers would optimize out such checks anyway in some
> > cases.
> > Nevertheless, I believe that putting it explicit makes the code easier to
> > understand for a human reader.
> 
> If you look at the bigger context, it's something like
> if (cc->foo) {
> ...
> }
> if (cc->bar) {
> ...
> }
> if (cc->baz) {
> ...
> }
> repeated maybe 17 times, and then suddenly
> if (cc && cc->xor) {
> ...
> }
> and it sort of makes you wonder if something suddenly could have
> changed cc, but indeed there is not.

Sorry for the confusion.  I wanted to say that your patch makes it easier to 
understand for a human reader (by not checking something that is guaranteed
to hold at that point).

Kamil