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From: Jonathan Wakely <jwakely.gcc@gmail.com>
To: Basile Starynkevitch <basile@starynkevitch.net>
Cc: Andrea Monaco <andrea.monaco@autistici.org>,
	"gcc@gcc.gnu.org" <gcc@gcc.gnu.org>
Subject: Re: No warning about duplicate values in enum
Date: Sat, 11 Mar 2023 16:48:14 +0000	[thread overview]
Message-ID: <CAH6eHdRioQx5qhxDBvx6wndS+i8AX9m7zTX05BqKSRCOx_j89w@mail.gmail.com> (raw)
In-Reply-To: <7785d160-cd05-01e2-e800-4bc82d630c4e@starynkevitch.net>

[-- Attachment #1: Type: text/plain, Size: 686 bytes --]

On Sat, 11 Mar 2023, 12:53 Basile Starynkevitch, <basile@starynkevitch.net>
wrote:

> Hello all,
>
>
> Andrea observed that:
>
> In gcc 8.3.0, compiling
>
>
> enum
> test
>    {
>      FIRST = 1,
>      SECOND = 1,
>      THIRD = 2
>    };
>
> int
> main (void)
> {
>    return 0;
> }
>
>
> generates no warning even with -Wextra.
>
> I believe that the C standard (which I don't have here, but see also
> https://port70.net/~nsz/c/c11/n1570.html or buy it from ISO) explicitly
> allow duplicate values in enum.
>


Of course it does, it's perfectly valid. Nobody has said it should be
rejected. The request is for a warning, because for *some* uses of enums
duplicates are not wanted.

  reply	other threads:[~2023-03-11 16:48 UTC|newest]

Thread overview: 6+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2023-03-11 12:54 Basile Starynkevitch
2023-03-11 16:48 ` Jonathan Wakely [this message]
2023-03-13 13:29   ` Marek Polacek
2023-03-13 13:38     ` Basile Starynkevitch
  -- strict thread matches above, loose matches on Subject: below --
2023-03-10 12:57 Andrea Monaco
2023-03-10 13:05 ` Marek Polacek

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