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From:   "Randall S. Becker" <rsbecker@nexbridge.com>
To:     "=?UTF-8?Q?'Ren=C3=A9_Scharfe'?=" <l.s.r@web.de>
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Subject: RE: unused variable in hashmap.h [was: Re: [PATCH] Fixed pervasive enumeration warning in convert.h.]
Date:   Sat, 13 Jan 2018 12:30:35 -0500
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> 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