[CI] Pin homebrew LLVM@9

[kszucs]

No description provided.

[github-actions]

Thanks for opening a pull request!

Could you open an issue for this pull request on JIRA?
https://issues.apache.org/jira/browse/ARROW

Then could you also rename pull request title in the following format?

ARROW-${JIRA_ID}: [${COMPONENT}] ${SUMMARY}

See also:

• Other pull requests
• Contribution Guidelines - How to contribute patches

[pprudhvi]

@ursabot crossbow submit -g gandiva

[pprudhvi]

@kszucs, @naman1996 tried to build gandiva with this change and it is failing when it tries to install llvm 10 as part of make. (see cpp/CmakeLists.txt)

p.s., is there a way to trigger gandiva nightly builds using ursabot? we were able to do @ursabot crossbow submit earlier.

[naman1996]

@github-actions crossbow submit gandiva*

[kou]

We need LLVM 8 for Clang Tools such as clang-tidy.

[kszucs]

@kou how about separating a Brewfile required for CI and one for local development?

[kou]

It's OK to me.
But I'm not sure we can maintain both of them.

[kou]

@github-actions crossbow submit -g gandiva

[github-actions]

Revision: a3076eb

Submitted crossbow builds: ursa-labs/crossbow @ actions-659

Task	Status
gandiva-jar-osx
gandiva-jar-xenial

[pprudhvi]

@github-actions crossbow submit -g gandiva

[github-actions]

Revision: a3076eb

Submitted crossbow builds: ursa-labs/crossbow @ actions-666

Task	Status
gandiva-jar-osx
gandiva-jar-xenial

[pprudhvi]

@kszucs , @kou Can we make gandiva-jar-osx build pass before merging this? If llvm10 is not available, cmake should pickup llvm9, somehow this is not happening.

[kou]

We don't need this once #8521 is merged.

@pprudhvi BTW, could you fix the gandiva-jar-xenial failure?
It seems that this is caused by f1f4001 .

[pprudhvi]

@kou we are working on it. Also, we will do the llvm11 upgrade in linux docker image for gandiva-jar-xenial later

[kou]

Great!

FYI: We can't use LLVM 11 on Ubuntu Xenial because g++ 5 on Ubuntu Xenial is old to use LLVM 11. LLVM 11 requires C++ 14 but g++ 5's C++ 14 support is limited.
We're using LLVM 8 for the deb package for Ubuntu Xenial: https://github.com/apache/arrow/blob/master/dev/tasks/linux-packages/apache-arrow/apt/ubuntu-xenial/Dockerfile#L32-L35

[kou]

I close this because #8521 is merged.