Re: [PATCH v2 0/2] sparc/build: Rework CFLAGS for clang compatibility

[Nathan Chancellor <nathan@kernel.org>]

On Wed, Oct 23, 2024 at 12:29:26PM +0900, Masahiro Yamada wrote:
> With running this command in Ubuntu 24.10, I got improvements,
> but I still got another build error.  (unknown argument: '-mv8plus')

> clang: error: unknown argument: '-mv8plus'
> make[5]: *** [scripts/Makefile.build:229:

> masahiro@3606c94ac88c:~/workspace/linux-kbuild$ clang --version
> Ubuntu clang version 19.1.1 (1ubuntu1)

> Is this version too old, or am I missing something?

Yes, that is the issue resolved by the pull request that Koakuma
mentioned in the changelog:

https://github.com/llvm/llvm-project/pull/98713
https://github.com/llvm/llvm-project/commit/6c270a8b9f1e1b80a6016aafb438db7dd89bcb99

which depends on some codegen changes too:

https://github.com/llvm/llvm-project/commit/aca971d336d9c7650120fc0fd6dfe58866408216

Those patches missed the LLVM 19 branch point by a couple of weeks:

https://github.com/llvm/llvm-project/commit/8f701b5df0adb3a2960d78ca2ad9cf53f39ba2fe

They are relatively simple, so maybe we would have a chance of
convincing the stable maintainer of LLVM to take them for a later 19.1
release but given how little usage this is likely to see until the full
LLVM stack is further developed, I am not sure that petition would be
worth it.

Cheers,
Nathan