Comment # 9 on bug 1221183 from Aaron Puchert

(In reply to Franz Sirl from comment #8)
> This pinning might be related to the divergence of the "clang" package
> between SLE and openSUSE. I remember it's quite hard to build a package
> requiring a newer clang on OBS. IIRC that's because requirements like "clang
> >= 9" don't work on SLE, but work in openSUSE. So in OBS the easy way out is
> to pin the version.

All of these packages are in Backports, where we have an up-to-date
metapackage.
(https://build.opensuse.org/package/show/openSUSE:Backports:SLE-15-SP6/llvm)

I checked Klee in detail a few days ago and it's actually not that easy. It
takes in additional sources that correspond to the LLVM version being used,
which makes it quite a bit harder to build against other supported versions.

> No idea if the clang divergence is by design or an oversight.

The earlier SPs had updates for the metapackage, but there is some reason
specific to how SLE is built that made it uncompelling to update it for later
SPs. Richard wrote somewhere that he would like to remove it if possible.

But I don't think there are a lot of LLVM users in SLE, I'm actually only aware
of Mesa. (Though some BPF-related tools and Rust might use it as well. They
usually want specific versions though.)