clang 10 -Wimplicit-fallthrough

Darren Tucker dtucker at
Sat Jun 6 11:45:10 AEST 2020

On Sat, 6 Jun 2020 at 03:07, Peter Stuge <peter at> wrote:
> Darren Tucker wrote:
> > Annotating these points with a FALLTHROUGH macro would make more
> > work keeping the code in sync and so is currently a non-starter.
> Upstream OpenSSH/OpenBSD has no interest in embracing such a macro?
> Isn't there some clang/llvm intent in OpenBSD?

OpenBSD uses clang 8 or gcc, depending on the architecture.  From
brief testing, clang 8 doesn't implement __attribute__((fallthrough))

That means to implement it in OpenBSD it'd require at least updating
the system compiler to clang 10 and possibly update gcc architectures
to clang before changing all of the FALLTHROUGHs.  This is scope creep
well beyond what I'm willing to engage in :-)

> Are you thinking to also add a test case for when it's missing?

No, because this test is used to with -Werror to determine which
warnings the compiler accepts.  If I did that it'll cause gcc to flag
it as an error and have the effect of disabling the warnings on gcc

Darren Tucker (dtucker at
GPG key 11EAA6FA / A86E 3E07 5B19 5880 E860  37F4 9357 ECEF 11EA A6FA (new)
    Good judgement comes with experience. Unfortunately, the experience
usually comes from bad judgement.

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