Subject: Re: [PATCH 1/3] configure.ac: more carefully detect availability of
 res_querydomain(3)
To:     Patrick Steinhardt <ps@pks.im>, linux-nfs@vger.kernel.org
References: <a6f2aaea93c1293e62d5109b10d47a7675a45393.1549290423.git.ps@pks.im>
 <20190222075202.GA13960@ncase>
From:   Steve Dickson <SteveD@RedHat.com>
Message-ID: <5d6ccf4a-2bee-f45b-5ef8-f8729185fd9f@RedHat.com>
Date:   Wed, 27 Feb 2019 11:41:47 -0500
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On 2/22/19 2:52 AM, Patrick Steinhardt wrote:
> On Mon, Feb 04, 2019 at 03:31:18PM +0100, Patrick Steinhardt wrote:
>> Since glibc 2.2, the function res_querydomain(3) is implemented as a
>> define to `__res_querydomain`. Due to this implementation detail, using
>> `AC_CHECK_LIB` with a symbol name of "res_querydomain" will cause a
>> linking failure and thus fail to detect its availability. This is why
>> right now, we try to detect availability of `__res_querydomain` instead.
>>
>> Unfortunately, this may break on other platforms where there is no
>> `__res_querydomain` but only the function without leading underscores.
>> To fix this, we can perform another `AC_CHECK_LIB([resolv],
>> [res_querydomain], ...)` call in case where the other one was not found
>> and only raise an error if both symbols weren't found.
>>
>> Signed-off-by: Patrick Steinhardt <ps@pks.im>
> 
> Is there anything I can do to get this rolling and improve my
> patches? Or did I accidentally pick the wrong mailing list for
> the userspace part of nfs?
Sorry about this... I'm looking at them now... 

steved.

> 
> Patrick
>