RE: unused variable in hashmap.h [was: Re: [PATCH] Fixed pervasive enumeration warning in convert.h.]

From: Randall S. Becker <rsbecker@nexbridge.com>
Date: Jan 13, 2018, 17:30 UTC
Message-ID: <002501d38c94$3b9efd00$b2dcf700$@nexbridge.com>
In-Reply-To: <f139ed79-1e12-d7b6-dd24-ce77000917ec@web.de>

Show 15 quoted lines

> Sent: On January 13, 2018 12:13 PM, René Scharfe wrote:
> Am 12.01.2018 um 20:52 schrieb Randall S. Becker:
> > On a related too many warnings subject, hashmap.h has a variable
> > unused (void *item). Is that addressed soon? If not, I can deal with
> > it.
> Here are the code lines containing the variable in question:
> 
>         void *item;
>         while ((item = hashmap_iter_next(&iter)))
> 
> Intriguing.  The variable "item" is set, but can be removed without effect.
> GCC 7.2 and Clang 5 don't warn about that.
> 
> The code was introduced by 8b604d1951 (hashmap: add API to disable item
> counting when threaded) and there is no patch in pu that touches it again,

I was thinking about just changing it to the following and submitting the trivial patch:

         while (hashmap_iter_next(&iter))

Avoids the frame allocation of void *item so should make it minimally faster when compiled without optimization.

Cheers, Randall