[build] Bump macos to 15, and print out the version and clang++ version, at s…

[hughperkins]

…tart of build

Issue: #

Brief Summary

I get the feeling from looking at the link to macos-latest on https://docs.github.com/en/actions/using-github-hosted-runners/using-github-hosted-runners/about-github-hosted-runners#standard-github-hosted-runners-for--private-repositories , which points to macos-14, and also looking at the version of clang++ in the logs, that we are not currently testing on the latest version of macos, which is 15 (sequoia). I feel that we should be. We cannot support multiple mac os versions I feel, and Apple push very clearly for everyone to be on the latest version.

This PR:

• bumps the os version to 15, i.e. the latest currenlty
• prints out clearly the os version, and the clang++ version, at the start of the m1 'build' step

copilot:summary

Walkthrough

copilot:walkthrough

[hughperkins]

(Note that I fully expect this build to fail, and then I have branches and stuff to address that:

• Questions about handling build for Mac 15 Sequoia on M4 #8686
• HOWTO: Building on Mac OS X Sequoia #8685

[feisuzhu]

/rebase

[hughperkins]

Hmmm, this mac build is still using a really old version of macos 🤔

ProductName:	macOS
ProductVersion:	11.7.2
BuildVersion:	20G1020
Apple clang version 13.0.0 (clang-1300.0.29.30)

(current product version is 15.4.1; and current clang is 17.0.0)

I wonder why that is 🤔

[hughperkins]

Ok, it's correctly on mac os 15.4.1 now 🙌

ProductName:		macOS
ProductVersion:		15.4.1
BuildVersion:		24E[26](https://github.com/taichi-dev/taichi/actions/runs/14742813933/job/41384420135?pr=8688#step:4:27)3
Apple clang version 16.0.0 (clang-1600.0.26.3)

[hughperkins]

Woo, MacOS build correctly fails 🙌

2025-04-29T23:01:39.8781870Z [W 04/29/25 23:01:31.994 67629] [misc.py:adaptive_arch_select@758] Arch=[<Arch.cuda: 3>] is not supported, falling back to CPU
2025-04-29T23:01:39.8782050Z [W 04/29/25 23:01:31.998 67629] [llvm_context.cpp:load@263] Bitcode loading error message:
2025-04-29T23:01:39.8782410Z Unknown attribute kind (86) (Producer: 'APPLE_1_1600.0.26.3_0' Reader: 'LLVM 15.0.7')
2025-04-29T23:01:39.8782880Z [E 04/29/25 23:01:31.998 67629] [llvm_context.cpp:load@265] Failed to load bitcode=/Users/runner/.cache/ti-build-cache/mambaforge/envs/3.9/lib/python3.9/site-packages/taichi/_lib/runtime/runtime_arm64.bc
2025-04-29T23:01:39.8783100Z Program aborted due to an unhandled Error:
2025-04-29T23:01:39.8783280Z Unknown attribute kind (86) (Producer: 'APPLE_1_1600.0.26.3_0' Reader: 'LLVM 15.0.7')

(I have fixed this on my own Mac, by building using the brew downloaded llvm@15. I will look into getting this build working with the brew installed llvm@15 too)

[hughperkins]

Note: I think the next step for MacOS 15 build is to upgrade glfw to latest master version, taichi-dev/glfw#2