use flang18 not flang5

[Krande]

I propose moving from flang v5 to flang v18 in order for downstream packages to compile using flang v18

Checklist

• Used a personal fork of the feedstock to propose changes
• Bumped the build number (if the version is unchanged)
• Re-rendered with the latest conda-smithy (Use the phrase @conda-forge-admin, please rerender in a comment in this PR for automated rerendering)
• Ensured the license file is being packaged.

[conda-forge-webservices]

Hi! This is the friendly automated conda-forge-linting service.

I just wanted to let you know that I linted all conda-recipes in your PR (recipe) and found it was in an excellent condition.

[Krande]

@conda-forge-admin, please rerender

[minrk]

I don't know enough to make a decision. Can you perhaps link to downstream packages this is affecting?

Perhaps it makes the most sense to check in with doing this conda-forge-wide: conda-forge/conda-forge-pinning-feedstock#1359

[Krande]

I don't know enough to make a decision. Can you perhaps link to downstream packages this is affecting?

Sure, I'll give it a shot.

Using

mamba repoquery whoneeds -c conda-forge --recursive scotch -p win-64

Returns only ptscotch and libptscotch which in turn results zero packages when searching for subsequent usage. I might using the repoquery command incorrectly though.

However, when I search for the packages relying on scotch on linux-64 it returns several packages, such as; petsc, mumps-seq, mumps-mpi, freefem, fenics-libdolfinx, code-aster and more.

So maybe there aren't any cf packages for windows that depends on scotch?

Perhaps it makes the most sense to check in with doing this conda-forge-wide: conda-forge/conda-forge-pinning-feedstock#1359

Yes, that's a good idea. I'll make a post there as soon as I am confident that LLVM Flang is ready. We're still working out some kinks in compiling HDF5 with fortran enabled for windows using Flang.

I was thinking if Scotch for windows is not used by any known packages on conda-forge, then maybe it would be good candidate for further testing of Flang? That way we could also try to build mumps-seq for windows against scotch.

I'm currently in no rush, so feel free to take your time to consider this proposal :)

[Krande]

@conda-forge-admin, please rerender