Re: [PATCH] x86: work around clang IAS bug referencing __force_order

[Sedat Dilek]

On Sat, Aug 22, 2020 at 10:42 AM Segher Boessenkool
<segher@xxxxxxxxxxxxxxxxxxx> wrote:
>
> Hi Arvind,
>
> On Fri, Aug 21, 2020 at 11:55:52PM -0400, Arvind Sankar wrote:
> > Cc Segher.
> >
> > Segher, we were looking at gcc PR82602, where IRA could reorder volatile
> > asm's (reported on ARM). The fix was backported to gcc-6.
>
> I know ;-)
>
> > Do you know if
> > there is any reason the problem couldn't occur on x86 on older gcc
> > without the fix?
>
> No, I see no particular reason, at least GCC 5 seems vulnerable.  (The
> GCC 5 release branch was closed at the time this bug report was made,
> already).  There is no reason I see why it would work on x86 but fail
> elsewhere, either.
>

[1] says:

Current Minimal Requirements
...
====================== ===============  ========================================
        Program        Minimal version       Command to check the version
====================== ===============  ========================================
GNU C                  4.9              gcc --version

- Sedat -

[1] https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/tree/Documentation/process/changes.rst#n32