Clarify development instructions regarding llvmlite dev releases

[esc]

As per Gitter:

We need to update the instructions at:

https://numba.readthedocs.io/en/latest/developer/contributing.html#build-environment?

So as to include installing an llvmlite release from. numba/label/dev.

[sgbaird]

This got rid of the error for me. Is this correct? (Source)
conda install -c numba/label/ci_llvmlite_0.38 llvmlite

[sgbaird]

Also, to improve the searchability of this issue, here is the text version of the error:

ImportError: Numba requires at least version 0.38.0 of llvmlite.
Installed version is 0.37.0.
Please update llvmlite.

[esc]

@sgbaird thank you for looking into this. I am not sure where the ci_llvmlite_0.38 channel came from. IIRC development releases of llvmlite can be obtained from the numba/label/dev channel on anaconda.org.

[esc]

the label on anaconda.org: ci_llvmlite_0.38 was removed, it was a temporary storage for some experimental packages.

[FirefoxMetzger]

I ran into the same issue while setting up a dev environment (new to numba, and preparing my first PR 😄). I guess the correct instruction to fix this is to use the dev channel as suggested by @esc ?

conda install -c numba/label/dev llvmlite

[esc]

I ran into the same issue while setting up a dev environment (new to numba, and preparing my first PR 😄). I guess the correct instruction to fix this is to use the dev channel as suggested by @esc ?

conda install -c numba/label/dev llvmlite

Yes, that is one correct way to obtain developmental releases of llvmlite.