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From: Tom Lane <tgl@sss.pgh.pa.us>
To: Peter Eisentraut <peter@eisentraut.org>
cc: Jelte Fennema-Nio <postgres@jeltef.nl>,
        pgsql-hackers <pgsql-hackers@postgresql.org>
Subject: Re: enable fallthrough warnings on clang
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Comments: In-reply-to Peter Eisentraut <peter@eisentraut.org>
	message dated "Tue, 07 Apr 2026 16:31:49 +0200"
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Date: Tue, 07 Apr 2026 10:35:27 -0400
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Peter Eisentraut <peter@eisentraut.org> writes:
> On 06.04.26 23:31, Tom Lane wrote:
>> BF member ayu is failing said test:
>> ...
>> I don't know if it's worth catering to this extremely old
>> clang version ...

> But AFAICT, clang 5 and older are completely broken in this regard, 
> because they react to the presence of [[clang::fallthrough]] with a 
> syntax error ("error: expected expression").  Not even clang's own 
> example code[0] works.

Hah, so we'd make it worse not better by adding
[[clang::fallthrough]].  Let's leave well enough alone then.

			regards, tom lane