[PATCH v1 00/35] Require GNU C --at least GCC 5 or Clang 4-- in headers

[H.J. Lu]

On Mon, Nov 10, 2025 at 6:36 AM Alejandro Colomar <alx@kernel.org> wrote:
>
> Hi Collin,
>
> On Sun, Nov 09, 2025 at 02:15:59PM -0800, Collin Funk wrote:
> > Alejandro Colomar <alx@kernel.org> writes:
> >
> > > Hi,
> > >
> > > Probably, not many people (if any) test all those old configurations.
> > > That code is likely to have bugs.  Let's remove it, which simplifies
> > > a lot of code, and allows us to write better new code.
> > >
> > > For now, I've raised the minimums to GCC 5 or Clang 4, but we can
> > > probably raise it further later.
> > >
> > > I've successfully tested for regressions on
> > >
> > >     $ uname -a
> > >     Linux devuan 6.16.12+deb14+1-amd64 #1 SMP PREEMPT_DYNAMIC Debian 6.16.12-2 (2025-10-16) x86_64 GNU/Linux
> >
> > Adding Bruno Haible to CC.
> >
> > Some of these changes are in files shared with Gnulib, which works
> > perfectly fine with GCC 4. We had someone building with GCC 4.1
> > recently, so it is still tested [1].
> >
> > I would like to avoid dropping old compiler support if possible. Guix
> > uses GCC 4 for bootstrapping [2]. If Gnulib drops support for it, I
> > assume it will make their lives harder.
>
> Would it be okay to raise the minimum to GCC 4?  That would already
> remove many hundreds of lines of code.
>
>

For installed headers, we should keep supporting the old compilers.

-- 
H.J.