Use the ACCESS toolchain version of Python

[harshula]

• Define an ACCESS-NRI approved Toolchain for Spack spack-config#121

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🚀 The latest prerelease access-om3/pr274-6 at cdcbe70 is here: #274 (comment) 🚀

[github-actions]

🚀 Attempted to deploy access-om3 Prerelease pr274-1 with commit 08e94b3

🖥️ Gadi Deployment ❌

[github-actions]

🚀 Attempted to deploy access-om3 Prerelease pr274-2 with commit e378a8f

🖥️ Gadi Deployment ❌

[github-actions]

🚀 Attempted to deploy access-om3 Prerelease pr274-3 with commit 438946b

🖥️ Gadi Deployment ❌

[github-actions]

🚀 Attempted to deploy access-om3 Prerelease pr274-4 with commit aec82b8

🖥️ Gadi Deployment ❌

[github-actions]

🚀 Attempted to deploy access-om3 Prerelease pr274-5 with commit 47df8de

🖥️ Gadi Deployment ✔️

Usage Instructions

access-om3, defined in spack.yaml, will be deployed to Gadi as:

• 2026.05.004 as a Release (when merged).
• pr274-5 as a Prerelease (during this PR).

This Prerelease is accessible on Gadi using:

module use /g/data/vk83/prerelease/modules
module load access-om3/pr274-5

When using the above modules, the binaries shall be on your $PATH.

For advanced users, this Prerelease is also accessible on Gadi via /g/data/vk83/prerelease/apps/spack/1.1/spack in the access-om3-pr274-5 environment.
Due to inode-saving measures, one will have to manually untar the environment metadata before environment activation with tar -xf .spack-env .spack-env.tar. It will require one to have write privileges.

Configuration Information

This Prerelease is deployed using:

• access-nri/spack on branch 1.1
• ACCESS-NRI/upstream-spack-packages version access/v1.1
• access-nri/access-spack-packages version 2026.09.005
• access-nri/spack-config version 2026.08.001

If the above was not what was expected, commit changes to the manifest in this PR, or propose changes to build-cds config/settings.json.

[harshula]

Spack does not appear to be reusing the external python@3.12.13:

[+]  osrv3by              ^python@3.12.13+bz2~crypt+ctypes+dbm~debug+libxml2+lzma~optimizations+pic+pyexpat+pythoncmd+readline+shared+sqlite3~ssl~static~tests~tkinter+uuid+zlib build_system=generic platform=linux os=rocky8 target=x86_64_v4 %c,cxx=oneapi@2025.2.0

Going to try and add a further constraint for python, namely, target=x86_64.

[github-actions]

🚀 Attempted to deploy access-om3 Prerelease pr274-6 with commit cdcbe70

🖥️ Gadi Deployment ✔️

Usage Instructions

access-om3, defined in spack.yaml, will be deployed to Gadi as:

• 2026.05.004 as a Release (when merged).
• pr274-6 as a Prerelease (during this PR).

This Prerelease is accessible on Gadi using:

module use /g/data/vk83/prerelease/modules
module load access-om3/pr274-6

When using the above modules, the binaries shall be on your $PATH.

For advanced users, this Prerelease is also accessible on Gadi via /g/data/vk83/prerelease/apps/spack/1.1/spack in the access-om3-pr274-6 environment.
Due to inode-saving measures, one will have to manually untar the environment metadata before environment activation with tar -xf .spack-env .spack-env.tar. It will require one to have write privileges.

Configuration Information

This Prerelease is deployed using:

• access-nri/spack on branch 1.1
• ACCESS-NRI/upstream-spack-packages version access/v1.1
• access-nri/access-spack-packages version 2026.09.005
• access-nri/spack-config version 2026.08.001

If the above was not what was expected, commit changes to the manifest in this PR, or propose changes to build-cds config/settings.json.

[harshula]

Spack used the external Python in the previous build when target=x86_64 was added:

[e]  prcl3bl              ^python@3.12.13+bz2+crypt+ctypes+dbm~debug+libxml2+lzma~optimizations+pic+pyexpat+pythoncmd+readline+shared+sqlite3+ssl~static~tests~tkinter+uuid+zlib build_system=generic platform=linux os=rocky8 target=x86_64

[dougiesquire]

Thanks @harshula. I was hoping we might be able to remove Python from the spack.yaml altogether