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From:   Geert Uytterhoeven <geert@linux-m68k.org>
Date:   Sun, 14 Nov 2021 16:32:02 +0100
Message-ID: <CAMuHMdXj8fHDq-eFd41GJ4oNwGD5sxhPx82izNwKxE_=x8dqEA@mail.gmail.com>
Subject: Re: [PATCH v16 1/3] fs: Add trusted_for(2) syscall implementation and
 related sysctl
To:     "Alejandro Colomar (man-pages)" <alx.manpages@gmail.com>
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Hi Alejandro,

On Sat, Nov 13, 2021 at 8:56 PM Alejandro Colomar (man-pages)
<alx.manpages@gmail.com> wrote:
> On 11/13/21 14:02, Mickaël Salaün wrote:
> >> TL;DR:
> >>
> >> ISO C specifies that for the following code:
> >>
> >>      enum foo {BAR};
> >>
> >>      enum foo foobar;
> >>
> >> typeof(foo)    shall be int
> >> typeof(foobar) is implementation-defined
> >
> > I tested with some version of GCC (from 4.9 to 11) and clang (10 and 11)
> > with different optimizations and the related sizes are at least the same
> > as for the int type.
>
> GCC has -fshort-enums to make enum types be as short as possible.  I
> expected -Os to turn this on, since it saves space, but it doesn't.

Changing optimization level must not change the ABI, else debugging
would become even more of a nightmare.

Gr{oetje,eeting}s,

                        Geert

--
Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert@linux-m68k.org

In personal conversations with technical people, I call myself a hacker. But
when I'm talking to journalists I just say "programmer" or something like that.
                                -- Linus Torvalds