There is an updated pull request by q66 against master on the void-packages repository

https://github.com/void-ppc/void-packages llvm9
https://github.com/void-linux/void-packages/pull/14656

llvm9
This adds llvm9, strips down llvm8 to a minimum (and updates it to 8.0.1), and bumps a bunch of other packages that should be bumped.

Platform testing:

- [ ] x86_64 **[need help]**
- [ ] x86_64-musl **[need help]**
- [ ] i686 **[need help]**
- [ ] ppc64le
- [ ] ppc64le-musl
- [ ] ppc64
- [ ] ppc64-musl
- [ ] ppc
- [ ] ppc-musl
- [ ] aarch64
- [ ] aarch64-musl
- [ ] armv7l **[need help]**
- [ ] armv6l **[need help]**
- [ ] armv7l-musl **[need help]**

To bump:

- [x] llvm
- [x] libcxxabi
- [x] libcxx
- [x] llvm-libunwind
- [ ] libGL
- [ ] beignet **[need help, x86 only]**
- [ ] libclc-git
- [ ] juCi++
- [ ] kdevelop
- [ ] rtags
- [ ] bcc
- [ ] python-bcc
- [ ] ccls
- [ ] clazy
- [ ] include-what-you-use
- [ ] shiboken2
- [ ]  codelite

Not sure if to bump:

- [ ] crystal

rebuild but not bump (no target llvm/clang dependency):

- [ ] ardour
- [ ]  afl **[need help, x86 only]**
- [ ]  blender
- [ ]  firefox
- [ ]  firefox-esr
- [ ]  icecat
- [ ]  thunderbird
- [ ]  bpftrace
- [ ] chromium **[need help, won't build here]**
- [ ]  qtcreator
- [ ]  gnome-builder
- [ ]  godot
- [ ] ispc
- [ ] yosys
- [ ]  rdedup
- [ ]  pijul

Rust will need to be bumped but we'll do that as a part of the upcoming Rust update to avoid building twice.

A patch file from https://github.com/void-linux/void-packages/pull/14656.patch is attached