Re: [PATCH] ubsan: don't mark __ubsan_handle_builtin_unreachable as noreturn

[Andrey Ryabinin]

On 02/05/2018 01:15 PM, Arnd Bergmann wrote:
> On Mon, Feb 5, 2018 at 10:02 AM, Andrey Ryabinin
> <aryabinin@xxxxxxxxxxxxx> wrote:
>>
>>
>> On 02/02/2018 06:47 PM, Arnd Bergmann wrote:
>>> gcc-8 complains about the prototype for this function:
>>>
>>> lib/ubsan.c:432:1: error: ignoring attribute 'noreturn' in declaration of a built-in function '__ubsan_handle_builtin_unreachable' because it conflicts with attribute 'const' [-Werror=attributes]
>>>
>>
>> That's actually a bug in GCC. In GCC __ubsan_handle_builtin_unreachable declared
>> with 'noreturn' and 'const' attributes:
>>
>> DEF_SANITIZER_BUILTIN(BUILT_IN_UBSAN_HANDLE_BUILTIN_UNREACHABLE,
>>                       "__ubsan_handle_builtin_unreachable",
>>                       BT_FN_VOID_PTR,
>>                       ATTR_COLD_CONST_NORETURN_NOTHROW_LEAF_LIST)
>>
>>
>> But const attribute doesn't make any sense for function that returns void or doesn't return at all.
>> Given that gcc-8 has not released yet, it would be better to fix this bug there.
> 
> Ok. Should I open a gcc bug, or will you take care of it?
> 

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=84210

>        Arnd
>