GNU bug report logs - #75964
Switching the Emacs build to -Wswitch-enum in src/

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Message #191 received at 75964 <at> debbugs.gnu.org (full text, mbox):

From: Stefan Monnier <monnier <at> iro.umontreal.ca>
To: Pip Cet <pipcet <at> protonmail.com>
Cc: acorallo <at> gnu.org, Eli Zaretskii <eliz <at> gnu.org>, eggert <at> cs.ucla.edu,
 75964 <at> debbugs.gnu.org, stefankangas <at> gmail.com
Subject: Re: bug#75964: Switching the Emacs build to -Wswitch-enum in src/
Date: Tue, 04 Feb 2025 13:17:36 -0500

>> should return 2, because I'd prefer that it aborts and/or that the
>> programmer have a way to say explicitly what should happen.  `default:`
>> works for that in the case where you have listed *all* the enum's
>> values, but then you get stiffed in the case where you add an enum value
>> because the compiler won't tell you that you forgot to update this
>> `switch` accordingly.
>
> But... that's precisely what -Wswitch-enum does!  It warns about a
> forgotten case even though there is also a default label!

But IIUC that breaks the other case, where you do want to use `default:`
to mean "any other (valid) enum value".


        Stefan

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