On Wed, May 27, 2026 at 9:11 AM H.J. Lu <[email protected]> wrote:
>
> On Wed, May 27, 2026 at 9:05 AM Andrew Pinski <[email protected]> wrote:
> >
> >
> >
> > On Tue, May 26, 2026, 5:59 PM H.J. Lu <[email protected]> wrote:
> >>
> >> On Wed, May 27, 2026 at 8:39 AM Andrew Pinski
> >> <[email protected]> wrote:
> >> >
> >> > On Tue, May 26, 2026 at 3:56 PM H.J. Lu <[email protected]> wrote:
> >> > >
> >> > > On Wed, May 27, 2026 at 6:41 AM Iain Sandoe <[email protected]> 
> >> > > wrote:
> >> > > >
> >> > > >
> >> > > >
> >> > > > > On 26 May 2026, at 22:35, H.J. Lu <[email protected]> wrote:
> >> > > > >
> >> > > > > On Tue, May 26, 2026 at 11:19 PM Iain Sandoe 
> >> > > > > <[email protected]> wrote:
> >> > > > >>
> >> > > > >> HJ,
> >> > > > >>
> >> > > > >> Bootstrap on 32b Darwin (and 64b Darwin with 32b multilib) is 
> >> > > > >> still broken after
> >> > > > >> more than three weeks,
> >> > > > >>
> >> > > > >> It is reasonable to have a temporary break if there is a trivial 
> >> > > > >> typo or other fix
> >> > > > >> that can be applied in a timely manner.
> >> > > > >>
> >> > > > >> However, in this case, it seems your initial design needed some 
> >> > > > >> amendment,
> >> > > > >> and that means a more complex fix is needed - which needs 
> >> > > > >> additional review.
> >> > > > >>
> >> > > > >> Today I now faced two concurrent bootstrap breaks on some 
> >> > > > >> platform versions
> >> > > > >> - this is just consuming time in a non-constructive manner.
> >> > > > >
> >> > > > > It only shows that maintainers pay no attention to Darwin.  In the 
> >> > > > > meantime,
> >> > > > > you can submit a very simple libssp patch to fix Darwin build by 
> >> > > > > changing
> >> > > > > __stack_chk_guard to unsigned long for Darwin.
> >> > > >
> >> > > > I find this unbelievable, and cannot think of any other maintainer 
> >> > > > who would
> >> > > > leave a regulalry-tested platform broken for weeks, and then try 
> >> > > > pass the blame
> >> > > > to reviewers for not being quick enough review band aid upon band 
> >> > > > aid.
> >> > > >
> >> > > > The responsibility for producing good reviewed patches lies with you 
> >> > > > - not
> >> > > > with other maintainers for platforms you break with bad patches, and 
> >> > > > not with
> >> > > > reviewers who might have more pressing things to address.
> >> > >
> >> > > I submitted a fix and suggested one line change to address Darwin 
> >> > > build.
> >> > > You choose to ignore my suggestion.
> >> > >
> >> > > > I would be very disappointed if this is what is considered to be 
> >> > > > “good community” behaviour.
> >> > > >
> >> > > > Iain
> >> > > > ** even with all your patches applied the testcases need work - it 
> >> > > > is not at all
> >> > > > helpful that you leave it to others to finish off your incomplete 
> >> > > > work.
> >> > > >
> >> > >
> >> > > I submitted patches to address regressions.   Some newly added tests 
> >> > > failed
> >> > > due to the existing libssp implementation bug.   You can xfail them if 
> >> > > ssp isn't
> >> > > provided in libc.
> >> >
> >> > So I am going to step into this mess and explain how this mess came
> >> > about in the first place.
> >> >
> >> > Here is the situation and the problem is stack_protect_guard looks
> >> > like a mess to begin with.
> >> > GCC documented it this way: `The type of this variable must be
> >> > @code{ptr_type_node}.`
> >> > So libssp followed this. BUT glibc, and many other libc's didn't
> >> > follow this document part. glibc (and many other libcs and linux
> >> > kernel even) used `uintptr_t`. And GCC didn't check the type
> >> > beforehand.
> >> >
> >> > And then HJL changed it to be a type which is the same size and
> >> > signedness as `uintptr_t` BUT not exactly the same (on some targets)
> >> > and also checking the type at this stage.
> >> > HJL didn't update libssp originally. So that broke some x86 targets
> >> > including darwin. And then when he changed libssp it still was broken
> >> > for i?86-darwin (32bit) because in that case the difference between
> >> > `unsigned long` and `unsigned int` which are not compatible at all.
> >> > (note systemd also needed a change too).
> >> >
> >> > So we are now in limbo right now where i?86-darwin is broken (and
> >> > x86_64-darwin because of multilib).
> >> >
> >> > I think we should revert the original patch which checked the type and
> >> > all other band-aids. And start over with a different fix for the
> >> > original issue here.
> >>
> >> This mess has been there for a very long time.  My patch just exposes
> >> it.   Requires ssp in libc should resolve most issues.
> >
> >
> > Yes our policy on reverting makes a mention of that issue:
> > Note that no distinction is made between patches which are themselves buggy 
> > and patches that expose latent bugs elsewhere in the compiler.
> >
>
> Are we going to address the ssp mess in GCC 17?

I opened:

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=125466


-- 
H.J.

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