[Rpm-ecosystem] How to make .spec Requires for libXXX.so.VER

[Igor Gnatenko]

On Sat, Aug 1, 2015 at 10:25 PM, Jan Kratochvil
<jan.kratochvil at redhat.com> wrote:
> Hi,
Hi,
>
> https://bugzilla.redhat.com/show_bug.cgi?id=1249325
>
> GDB requires some library libXXX.so.3 by dlopen().  Therefore it is not found
> by rpm automatic requires/provides from DT_NEEDED.  Therefore one has to add
> the libXXX.so.3 by specific BuildRequires and Requires to the .spec file.
>
> libXXX is librpm here but that is just a coincidence, it could be libz for
> example.
>
> (1) How to make a dependency on librpm.so.7?
>
> librpm.so.7 is in rpm-libs-4.12.90-3.fc24.x86_64 which --provides:
>         librpm.so.7()(64bit)
>         librpmio.so.7()(64bit)
>         rpm-libs = 4.12.90-3.fc24
>         rpm-libs(x86-64) = 4.12.90-3.fc24
> So there is no easy way to Requires: rpm-libs = NVRA
> I do not see which V introduced / deprecates .so library version 7.
>
> So I would like to: Requires: librpm.so.7
> But that does not work as I need there the '()(64bit)' suffix.
>
> %{?_isa} suffix does not work, that is '(x86-64)' and not '()(64bit)'.
>
> I could %ifarch explicitly all 64-bit Fedora archs to append '()(64bit)' for
> them but isn't there some better way how to generate the '()(64bit)' suffix?
>
> (2) The other possibility does work:
>
>         BuildRequires: %{_libdir}/librpm.so.7
>
> But
>         https://fedoraproject.org/wiki/Packaging:Guidelines#File_Dependencies
> says
>         Whenever possible you should avoid file dependencies as they slow down
>         dependency resolution and require the package manager to download file
>         lists in addition to to regular dependency information.

I'd propose to add something like:
%if %{__isa_bits} = 64
Requires: libFOO.so.X()(64bit)
%else
Requires: libFOO.so.X
%endif

Not sure about syntax.
https://github.com/rpm-software-management/rpm/blob/140744377b019e0de81d76d0931c32228d2ed57e/tools/elfdeps.c#L81-L97
>
> From what I remember at least yum did not need the 'filelists' index for
> /usr/bin/ files.  Is it still valid today and also for dnf?
> And is 'filelists' required for /usr/lib{,64}/ or not?
You can add BuildRequires: /usr/bin/bar
>
> I think Packaging Guidelines could list these few directories - at least
> /usr/bin/ - for safe file dependencies.

Also CCing rpm maillist
>
>
> Thanks,
> Jan

-- 
-Igor Gnatenko