Request: Investigate utilisation of versioned toolchains for improved hermeticity

[jake-arkinstall]

In Bazel it's possible to force a specific compiler version with a custom toolchain that includes the download as part of the build process. For example, https://github.com/grailbio/bazel-toolchain.

I wonder if it's feasible to utilise something like this for this project, instead of requiring the host to have a specific clang version installed. Benefits could include more user friendly installation, seemless updating, and a tighter coupling between each commit and the required compiler version (the object files might even be built with the same toolchain to guarantee a match).

Not sure on the downsides, so that's why I'm making this issue a request to investigate.

[aluebs]

I wasn't aware of this option, but it is a great suggestion! :)

[aluebs]

With the new Lyra v0.0.2 the specific clang version isn't necessary anymore.