https://gcc.gnu.org/bugzilla/show_bug.cgi?id=114437
Andrew Pinski <pinskia at gcc dot gnu.org> changed:
What |Removed |Added
----------------------------------------------------------------------------
Resolution|INVALID |DUPLICATE
--- Comment #4 from Andrew Pinski <pinskia at gcc dot gnu.org> ---
(In reply to xog4nar4 from comment #3)
> Just to confirm, is this an incorrect constraint for the intended goal of
> convincing the compiler that the value is used and modified, without
> actually doing either and preserving the value, or am I just using it wrong
> in this particular example? I'm somewhat surprised since this inline asm
> snippet is used in multiple well-known micro-benchmarking libraries.
>
>
> Is the following version correct?
> ```
> asm volatile("" : "=m,r"(arg) : "0,0"(arg) : "memory");
> ```
The correct way of implementing this inline-asm is don't. Oh and the above does
not work either because a constraint of `"=m":"0"` is also not going to work.
Inline-asm is really NOT designed for this purpose at all and abusing it this
way is just going to run into these issues.
*** This bug has been marked as a duplicate of bug 92597 ***
