[FFmpeg-devel] [PATCH] OS/2:Support linking against libcx

[Dave Yeo]

On 06/13/20 07:03 AM, KO Myung-Hun wrote:
> Hi/2.
>
> Dave Yeo wrote:
>> On 06/11/20 10:26 AM, Michael Niedermayer wrote:
>>> On Wed, Jun 10, 2020 at 09:24:51PM -0700, Dave Yeo wrote:
>>>> On 06/10/20 02:09 PM, Michael Niedermayer wrote:
>>>>> On Tue, Jun 09, 2020 at 11:11:48PM -0700, Dave Yeo wrote:
>>>>>> Hi, could I get this pushed to trunk and the 4.3 branch? Fixes a
>>>>>> build break
>>>>>> in libavformat/ip.c (implicit declaration of function
>>>>>> 'getaddrinfo') and
>>>>>> also need the prototype.
>>>>>> Thanks,
>>>>>> Dave
>>>>> it seems this breaks build on linux
>>>>
>>>> Sorry about that, I'll test on Linux in the future.
>>>> Here's a better patch as it doesn't touch configure.
>>>> Thanks,
>>>> Dave
>>>
>>> I can confirm this does not break build anymore, but iam not OS/2
>>> maintainer nor do i have such box so ill leave review / application
>>> to someone better suited for this
>>>
>>> thx
>>> [...]
>>
>> Fair enough, I'll CC KOMH
>
> I have no problems at all with gcc 9.1.0 because FFmpeg already has
> replacements for missing functions such as getaddrinfo().
>
> What is your build environment ? Maybe is libcx linked by default ?
>

The problem only occurs if I link in libcx, LIBS=-lcx.
Note that with libcx, the build system finds its getaddrinfo() and later 
fails due to no prototype and will also fail as part of the addrinfo 
struct uses a different type (char vs int IIRC). Without LIBS=-lcx, the 
build falls back to FFmpeg's builtin getaddrinfo().
One of the main reasons to link to libcx is for the exceptq support. 
Also as it is recommended, others are likely to do the same thing.
Dave