Re: [PATCH 02/27] x86/syscalls: fix -Wmissing-prototypes warnings from COND_SYSCALL()

Sergei Shtylyov
2021-01-28T08:03:14Z

On 28.01.2021 10:59, Sergei Shtylyov wrote:

[...]
>> Building kernel/sys_ni.c with W=1 omits tons of -Wmissing-prototypes
>
>    Emits?
>
>> warnings.
>>
>> $ make W=1 kernel/sys_ni.o
>>    [ snip ]
>>    CC      kernel/sys_ni.o
>> In file included from kernel/sys_ni.c:10:
>> ./arch/x86/include/asm/syscall_wrapper.h:83:14: warning: no previous
>> prototype for '__x64_sys_io_setup' [-Wmissing-prototypes]
>>     83 |  __weak long __##abi##_##name(const struct pt_regs *__unused) \
>>        |              ^~
>> ./arch/x86/include/asm/syscall_wrapper.h:100:2: note: in expansion of macro
>> '__COND_SYSCALL'
>>    100 |  __COND_SYSCALL(x64, sys_##name)
>>        |  ^~~~~~~~~~~~~~
>> ./arch/x86/include/asm/syscall_wrapper.h:256:2: note: in expansion of macro
>> '__X64_COND_SYSCALL'
>>    256 |  __X64_COND_SYSCALL(name)     \
>>        |  ^~~~~~~~~~~~~~~~~~
>> kernel/sys_ni.c:39:1: note: in expansion of macro 'COND_SYSCALL'
>>     39 | COND_SYSCALL(io_setup);
>>        | ^~~~~~~~~~~~
>> ./arch/x86/include/asm/syscall_wrapper.h:83:14: warning: no previous
>> prototype for '__ia32_sys_io_setup' [-Wmissing-prototypes]
>>     83 |  __weak long __##abi##_##name(const struct pt_regs *__unused) \
>>        |              ^~
>> ./arch/x86/include/asm/syscall_wrapper.h:120:2: note: in expansion of macro
>> '__COND_SYSCALL'
>>    120 |  __COND_SYSCALL(ia32, sys_##name)
>>        |  ^~~~~~~~~~~~~~
>> ./arch/x86/include/asm/syscall_wrapper.h:257:2: note: in expansion of macro
>> '__IA32_COND_SYSCALL'
>>    257 |  __IA32_COND_SYSCALL(name)
>>        |  ^~~~~~~~~~~~~~~~~~~
>> kernel/sys_ni.c:39:1: note: in expansion of macro 'COND_SYSCALL'
>>     39 | COND_SYSCALL(io_setup);
>>        | ^~~~~~~~~~~~
>>    ...
>>
>> __SYS_STUB0() and __SYS_STUBx() defined a few lines above have forward
>> declarations. Let's do likewise for __COND_SYSCALL() to fix the
>> warnings.
>>
>> Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
>> ---
>>
>>   arch/x86/include/asm/syscall_wrapper.h | 1 +
>>   1 file changed, 1 insertion(+)
>>
>> diff --git a/arch/x86/include/asm/syscall_wrapper.h
>> b/arch/x86/include/asm/syscall_wrapper.h
>> index a84333adeef2..80c08c7d5e72 100644
>> --- a/arch/x86/include/asm/syscall_wrapper.h
>> +++ b/arch/x86/include/asm/syscall_wrapper.h
>> @@ -80,6 +80,7 @@ extern long __ia32_sys_ni_syscall(const struct pt_regs
>> *regs);
>>       }
>>   #define __COND_SYSCALL(abi, name)                    \
>> +    __weak long __##abi##_##name(const struct pt_regs *__unused);    \
>>       __weak long __##abi##_##name(const struct pt_regs *__unused)    \
>
>    Aren't these two lines identical?

Ah, got it! :-)

[...]

MBR, Sergei