Comment # 3 on bug 1164454 from Max Lin

(In reply to Richard Biener from comment #1)
> What are the actual duplicate binaries?  For SLE15 none fo the above cited
> sub-packages should make it to the media, for Leap we probably want the
> full llvm9 though.

The actual duplicated binaries:
libc++-devel, libc++1, libc++abi-devel, libc++abi1 and python3-clang RPMs,
llvm7 and llvm9 both had provide those RPMs. For Leap, if we had both full
llvm9 and full llvm7, OBS scheduler will just picks one of duplicated RPM if
any package build requires it.

> 
> libc++1, yes - doing it properly would need some similar mechanism as
> we have for the GCC runtime (some %define as to which one becoming
> the main one in the project config and suffixing the other).
> 
> What's the solution for Factory here?  Ah, we update the old package to
> no longer build libcxx and python3-clang.
> 
> The spec file says
> 
> # install python bindings
> # The python bindings use the unversioned libclang.so,
> # so it doesn't make sense to have multiple versions of it
> %if %{with pyclang}
> install -d %{buildroot}%{python3_sitelib}/clang
> 
> Note applying the Factory solution to SLE would mean updating llvm7 in
> SP2 and thus splitting it, requiring future maint updates to be done
> twice, once for SP1 and once for SP2+ which doesn't sound appealing to me.
> 
> Can't you apply some magic to the "product config" to prefer the llvm9
> variants for Leap?

for duplicated RPMs, prefer llvm9 variants has not fix this issue, Prefer: is
used for RPM.