On 11/02/2018 04:46 AM, Linus Torvalds wrote:
> On Thu, Nov 1, 2018 at 10:06 AM Linus Torvalds
> <torva...@linux-foundation.org> wrote:
>>
>> The logic for using __no_sanitize_address *used* to be
>>
>> #if GCC_VERSION >= 40902
>
> Ok, looking around, I think this has less to do with the attribute
> being recognized, and simply just being because KASAN itself wants
> gcc-4.9.2.
>
> I'm actually not seeing that KASAN dependency in the Kconfig scripts
> (and it probably _should_ be now that we can just add compiler version
> dependencies there), but that explains why the gcc version check is
> different from "gcc supports the attribute".
>
> Anyway, I decided to do the merge by just getting rid of the
> GCC_VERSION check around __no_sanitize_address_or_inline entirely. If
> you enable KASAN, then a function with that marking just won't be
> marked inline.
>
> End result: pulled. I'm as confused as you are as to why
> __no_sanitize_address_or_inline is in the gcc header, but I guess it
> ends up being the same issue: KASAN depends on gcc even if that
> dependency doesn't seem to be spelled out in lib/Kconfig.kasan.
>
> So I _think_ the KASAN config should have a
>
> depends on CC_IS_GCC && GCC_VERSION >= 40902
>
> on it, but maybe there is something I'm missing.
>
I'd rather use cc-option instead of version check, since we also support clang.
It should be possible to express compiler requirements for subfeatures
like stack/inline instrumentation in Kconfig. But that would be not that
trivial,
see the scripts/Makefile.kasan
> But from a pull standpoint, I don't want to mess with those
> (unrelated) issues, so I just kept the merge resolution as simple and
> straightforward as possible.
>
> Miguel, please do double-check the merge (it's not pushed out yet, I'm
> doing the usual build tests etc first).
>
> Linus
>
