From: Ævar Arnfjörð Bjarmason <avarab@gmail.com>
Date: Sun, 11 Nov 2018 20:10:17 GMT
Subject: Re: [PATCH 03/10] fast-export: use value from correct enum
Message-ID: <87va532x5i.fsf@evledraar.gmail.com>
In-Reply-To: <20181111063636.GC30850@sigill.intra.peff.net>


On Sun, Nov 11 2018, Jeff King wrote:

> On Sat, Nov 10, 2018 at 10:23:05PM -0800, Elijah Newren wrote:
>
>> ABORT and ERROR happen to have the same value, but come from differnt
>> enums.  Use the one from the correct enum.
>
> Yikes. :)
>
> This is a good argument for naming these SIGNED_TAG_ABORT, etc. But this
> is obviously an improvement in the meantime.

In C enum values aren't the types of the enum, but I'd thought someone
would have added a warning for this:

    #include <stdio.h>

    enum { A, B } foo = A;
    enum { C, D } bar = C;

    int main(void)
    {
        switch (foo) {
          case C:
            puts("A");
            break;
          case B:
            puts("B");
            break;
        }
    }

But none of the 4 C compilers (gcc, clang, suncc & xlc) I have warn
about it. Good to know.