Re: kernel/sched/syscalls.c:979:8: error: unexpected token, expected comma

From: Nathan Chancellor
Date: Mon Apr 14 2025 - 19:09:43 EST


Hi Philip,

On Sun, Apr 13, 2025 at 10:23:43AM +0800, Philip Li wrote:
> + llvm mailing list to consult
>
> On Thu, Apr 10, 2025 at 08:56:26AM +0200, Ingo Molnar wrote:
> >
> > * kernel test robot <lkp@xxxxxxxxx> wrote:
> >
> > > Hi Ingo,
> > >
> > > FYI, the error/warning still remains.
> > >
> > > tree: https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git master
> > > head: 0af2f6be1b4281385b618cb86ad946eded089ac8
> > > commit: 04746ed80bcf3130951ed4d5c1bc5b0bcabdde22 sched/syscalls: Split out kernel/sched/syscalls.c from kernel/sched/core.c
> > > date: 11 months ago
> > > config: mips-randconfig-r064-20250408 (https://download.01.org/0day-ci/archive/20250408/202504082254.7GLSWAbI-lkp@xxxxxxxxx/config)
> > > compiler: clang version 21.0.0git (https://github.com/llvm/llvm-project 92c93f5286b9ff33f27ff694d2dc33da1c07afdd)
> > > reproduce (this is a W=1 build): (https://download.01.org/0day-ci/archive/20250408/202504082254.7GLSWAbI-lkp@xxxxxxxxx/reproduce)
> >
> > I cannot reproduce this.
>
> Hi Ingo, looks this problem is clang + mips specific, and it can be traced back to
> early days like [1] [2] on different commits/files
>
> >> lib/usercopy_kunit.c:205:2: error: unexpected token, expected comma
> >> net/mctp/af_mctp.c:259:6: error: invalid operand for instruction
>
> I add llvm mailing list to consult for this behavior, and it's possible the bot
> environment is not correctly setup for this case.

No, I do not think this is a bot configuration issue, I think this is an
"our matrix is not very big for MIPS" issue so we just have not seen
this issue come up yet. Based on my brief research, this appears to be
an LLVM issue so I will follow up on trying to get that fixed later
(MIPS is rather low priority):

https://github.com/ClangBuiltLinux/linux/issues/2086

Cheers,
Nathan