Re: Really enable -fstack-clash-protection on armhf/armel?

* Emanuele Rocca:

> Hello!
>
> On 2023-11-24 01:34, Guillem Jover wrote:
>> According to https://bugs.debian.org/918914#73 there were no pending
>> toolchain issues related to this.
>
> That is correct. The GCC maintainers at Arm confirm that
> stack-clash-protection is supported on 32 bit too.

Jeff Law, the original designer of -fstack-clash-protection,
disagrees:

| So to reiterate, this is precisely the kind of problem we avoid by
| having stack-clash specific prologues on the Red Hat Enterprise
| Linux architectures.  We didn't do a 32bit ARM implementation and
| instead rely on the limited protections provided by the Ada
| -fstack-check bits.

<https://bugzilla.redhat.com/show_bug.cgi?id=1522678#c1>

And as far as I can see the code has not changed since then.

It's a bit unfortunate that GCC accepts the -fstack-clash-protection
flag even if target support is not really there.

Note that RISC-V has the same problem, but at least Jeff has mid-term
plans to fix that.