Re: [PATCH] MIPS: Add comment about CONFIG_MIPS32_O32 in loongson3_defconfig when build with Clang

在 2021/3/5 上午7:08, Maciej W. Rozycki 写道:

On Thu, 4 Mar 2021, Tiezhu Yang wrote:

quoted

This is a known bug [2] with Clang, as Simon Atanasyan said,
"There is no plan on support O32 for MIPS64 due to lack of
resources".

  Huh?  Is that a joke?  From the o32 psABI's point of view a MIPS64 CPU is
exactly the same as a MIPS32 one (for whatever ISA revision), so there's
nothing to support there really other than the CPU/ISA name.

Clang treat MIPS32 as a different backend so we may need some extra 
effort....

TBH it is a toolchain issue and kernel workaround seems bogus.

 From my point view we can "s/mips64r2/mips32r2" when doing syscall checks
to workaround clang issue instead of disable it for kernel.

Thanks.

- Jiaxun

  As much as I dislike all the hacks the Clang community seems to come up
with for the shortcomings of their tool there has to be a saner workaround
available rather than forcibly disabling support for the o32 ABI with
CONFIG_64BIT kernels, but the report is missing the compiler invocation
line triggering the issue (V=1 perhaps?), which should be included with
any commit description anyway, so I can't suggest anything based on the
limited information provided.

   Maciej