[PATCH v5] riscv: Handle zicsr/zifencei issue between gcc and binutils

[Mingzheng Xing]

On 8/23/23 21:31, Conor Dooley wrote:
> On Wed, Aug 23, 2023 at 12:51:13PM +0100, Conor Dooley wrote:
>> On Thu, Aug 17, 2023 at 03:20:24PM +0000, patchwork-bot+linux-riscv at kernel.org wrote:
>>> Hello:
>>>
>>> This patch was applied to riscv/linux.git (fixes)
>>> by Palmer Dabbelt <palmer at rivosinc.com>:
>>>
>>> On Thu, 10 Aug 2023 00:56:48 +0800 you wrote:
>>>> Binutils-2.38 and GCC-12.1.0 bumped[0][1] the default ISA spec to the newer
>>>> 20191213 version which moves some instructions from the I extension to the
>>>> Zicsr and Zifencei extensions. So if one of the binutils and GCC exceeds
>>>> that version, we should explicitly specifying Zicsr and Zifencei via -march
>>>> to cope with the new changes. but this only occurs when binutils >= 2.36
>>>> and GCC >= 11.1.0. It's a different story when binutils < 2.36.
>>>>
>>>> [...]
>>> Here is the summary with links:
>>>    - [v5] riscv: Handle zicsr/zifencei issue between gcc and binutils
>>>      https://git.kernel.org/riscv/c/ca09f772ccca
>> *sigh* so this breaks the build for gcc-11 & binutils 2.37 w/
>> 	Assembler messages:
>> 	Error: cannot find default versions of the ISA extension `zicsr'
>> 	Error: cannot find default versions of the ISA extension `zifencei'
>>
>> I'll have a poke later.
> So uh, are we sure that this should not be:
> -       depends on (CC_IS_CLANG && CLANG_VERSION < 170000) || (CC_IS_GCC && GCC_VERSION < 110100)
> +       depends on (CC_IS_CLANG && CLANG_VERSION < 170000) || (CC_IS_GCC && GCC_VERSION <= 110100)
>
> My gcc-11.1 + binutils 2.37 toolchain built from riscv-gnu-toolchain
> doesn't have the default versions & the above diff fixes the build.

I reproduced the error, the combination of gcc-11.1 and
binutils 2.37 does cause errors. What a surprise, since binutils
2.36 and 2.38 are fine.

I used git bisect to locate this commit[1] for binutils.
I'll test this diff in more detail later. Thanks!

[1] 
https://sourceware.org/git/?p=binutils-gdb.git;a=commit;h=f0bae2552db1dd4f1995608fbf6648fcee4e9e0c

Best Regards,
Mingzheng.

>
> Thanks,
> Conor.