Errors in packages with julia v1.7-beta2: problem with package or julia?

I have seen a couple of places where code runs with julia 1.6, but not 1.7-beta2. In particular:

  • MCMCChains.jl, the Chains function. chn=Chains(rand(10,2), ["a", "b"]) works fine on 1.6, errors on 1.7

  • BSON.jl: loading Flux model that was saved using 1.6 does not work with 1.7beta2. This problem seems to have a PR which would allow BSON to save data with 1.7, but it’s not clear that BSON would be able to load files saved with julia 1.6, when running with 1.7.

What’s not clear to me is if these are package problems, or a Julia problem. Where should this sort of issue be reported?

I’d say start with the package - technically I suppose it shouldn’t be a Julia problem (as minor releases shouldn’t break your code), unless of course the code relies on undocumented internals which are outside the SemVer stability guarantee. The package authors are probably best placed to answer the question whether they are relying on internals, and if they aren’t, an issue should be raised on the main Julia repo.


BSON.jl definitely relies on internals— check out e.g.