qt5 as default?

[Kevin Kofler]

Rex Dieter wrote:

> Antti J=?iso-8859-1?B?5A==?=rvinen wrote:
> 
>> There is also same decision to make regarding libraries that have not
>> been re-packaged to support both qt4 and qt5. One good example is
>> https://admin.fedoraproject.org/pkgdb/package/qjson/
>> -> there is no separate binary package libqjson-qt5 and libqjson-qt4. The
>> library from source works all right with both but if the library is
>> built and linked against qt4, it can also be used to build application
>> that links against qt5 and everything goes all right. Only downside is
>> immediate SIGSEGV when you invoke methods from the library :)
> 
> For libraries that support both, the general best practice is to change
> library soname for Qt5 builds, to ensure the scenarios you describe
> doesn't happen accidentally.

And to be clear, for libraries, you should usually be shipping BOTH builds, 
in separate subpackages. So yes, there needs to be a libqjson-qt5 and a 
libqjson-qt4 (but one of them should probably just keep the libqjson name 
and Provide the libqjson-qt* one).

And as Rex wrote, if upstream builds them with the same soname, this must be 
patched to allow the libraries to coexist, and you should also complain 
about this to upstream.

        Kevin Kofler