clang 13

[isuruf]

Checklist

• Used a personal fork of the feedstock to propose changes
• Bumped the build number (if the version is unchanged)
• Reset the build number to 0 (if the version changed)
• 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-linter]

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.

[isuruf]

@conda-forge/core, this is ready.

[beckermr]

This build

https://dev.azure.com/conda-forge/feedstock-builds/_build/results?buildId=495884&view=logs&jobId=58ac6aab-c4bc-5de2-2894-98e408cc8ec9&j=58ac6aab-c4bc-5de2-2894-98e408cc8ec9&t=933f325c-924e-533d-4d95-e93b5843ce8b

with the new 13 failed asking for a very old version 4. Did we miss something here?

[isuruf]

Need to rebuild compilers-feedstock

[beckermr]

Ahh thank you. It'd be nice to automate this process but maybe the compilers feedstock is on the margins of support.