Re: [clang] stack protector and f1f029c7bf

[H. Peter Anvin]

On 05/25/18 13:36, Nick Desaulniers wrote:
> On Fri, May 25, 2018 at 10:56 AM <hpa@xxxxxxxxx> wrote:
>> You need the extern inline in the .h file and the out-of-line .S file
> both.
> 
> But the out-of-line .S file looks like:
> 
> ...
>     10 ENTRY(native_save_fl)
> 
>     11   pushf
> 
>     12   pop %_ASM_AX
> 
>     13   ret
> 
>     14 ENDPROC(native_save_fl)
> 
>     15 EXPORT_SYMBOL(native_save_fl)
> ...
> 
> I don't see how you can specify to the linker from assembly source that
> this function should be treated as `extern inline`?
> 

"extern inline" is a C directive. In the header file you should provide
the inlinable implementation (which is already there.) It means that "if
you don't want to inline this there is an external implementation
available."


> I assume you don't literally mean the C keywords `extern inline` but
> whatever the equivalent incantation is needed in terms of assembler
> directives (which I also don't know).
> 
> I'm beginning to think that what you'd like to see cannot be expressed (at
> least via `extern inline`).
>