Re: lots of unused variable warnings in assert-free builds

On Sun, Jan 15, 2012 at 1:14 PM, Andrew Dunstan <andrew(at)dunslane(dot)net> wrote:
>
>
> On 01/15/2012 01:37 AM, Tom Lane wrote:
>>
>> Peter Eisentraut<peter_e(at)gmx(dot)net>  writes:
>>>
>>> I see that in some places our code already uses #ifdef
>>> USE_ASSERT_CHECKING, presumably to hide similar issues.  But in most
>>> cases using this would significantly butcher the code.  I found that
>>> adding __attribute__((unused)) is cleaner.  Attached is a patch that
>>> cleans up all the warnings I encountered.
>>
>> Surely this will fail entirely on most non-gcc compilers?  Not to
>> mention that next month's gcc may complain "hey, you used this 'unused'
>> variable".  I think #ifdef USE_ASSERT_CHECKING is really the only way
>> if you care about quieting these warnings.  (Personally, I don't.)
>>
>>
>
>
>
> It would possibly have some documentary value too. Just looking very quickly
> at Peter's patch, I don't really understand his assertion that this would
> significantly butcher the code. The worst effect would be that in a few
> cases we'd have to break up multiple declarations where one of the variables
> was in this class. That doesn't seem like a tragedy.
>
> I like software that compiles in the normal use with few or no warnings. I
> should have thought that would appeal to most packagers, too.

Sounds good, but let's not do it yet because we have a few patches to
commit first.

It would be good to minimise bit rot during the CF.

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