[x264-devel] [PATCH 1/2] macosx: version the libraries

[Sean McGovern]

On 3/7/12, Gil Pedersen <gil at cmi.aau.dk> wrote:
> On 07/03/2012, at 15.04, Sean McGovern wrote:
>
>> On 3/7/12, Gil Pedersen <gil at cmi.aau.dk> wrote:
>>> What is the rationale behind this change?
>>
>> Versioning parity between the ELF and Mach-O versions of the library.
>
> How so? On Linux the version is not represented in the .so itself, only
> through a naming convention. Why does Mach-O need the information encoded
> otherwise?
>

>From my Solaris 10 box (another ELF platform):

$ objdump -x libx264.so | grep SONAME
SONAME libx264.so.122

Linux doesn't do this?

>>> It will require a recompile of anything that links against libx264 and
>>> cause
>>> incompatible programs to crash when started. I don't see any benefits to
>>> the
>>> change when libx264 already has a link time check that will crash the
>>> calling app when x264_encoder_open() is called.
>>
>> Isn't this also true when the ELF soname changes?
>
> Which of my statements you are referring to?

An intelligent dynamic linker would refuse to link against this
library if the calling application requested libx264.so.122 -- which
seems proper behaviour for us since I don't think we do any backwards
compatibility testing when we bump the major version.

-- Sean McG.