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Message-ID: <dbd2cb703ed9eefa7dde9281ea26ab0f7acc8afe.camel@HansenPartnership.com>
Subject: Re: [PATCH 000/141] Fix fall-through warnings for Clang
From:   James Bottomley <James.Bottomley@HansenPartnership.com>
To:     Joe Perches <joe@perches.com>, Kees Cook <keescook@chromium.org>,
        Jakub Kicinski <kuba@kernel.org>
Cc:     "Gustavo A. R. Silva" <gustavoars@kernel.org>,
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Date:   Sun, 22 Nov 2020 11:53:55 -0800
In-Reply-To: <d8d1e9add08cdd4158405e77762d4946037208f8.camel@perches.com>
References: <cover.1605896059.git.gustavoars@kernel.org>
         <20201120105344.4345c14e@kicinski-fedora-pc1c0hjn.dhcp.thefacebook.com>
         <202011201129.B13FDB3C@keescook>
         <20201120115142.292999b2@kicinski-fedora-pc1c0hjn.dhcp.thefacebook.com>
         <202011220816.8B6591A@keescook>
         <9b57fd4914b46f38d54087d75e072d6e947cb56d.camel@HansenPartnership.com>
         <ca071decb87cc7e905411423c05a48f9fd2f58d7.camel@perches.com>
         <0147972a72bc13f3629de8a32dee6f1f308994b5.camel@HansenPartnership.com>
         <d8d1e9add08cdd4158405e77762d4946037208f8.camel@perches.com>
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On Sun, 2020-11-22 at 11:22 -0800, Joe Perches wrote:
> On Sun, 2020-11-22 at 11:12 -0800, James Bottomley wrote:
> > On Sun, 2020-11-22 at 10:25 -0800, Joe Perches wrote:
> > > On Sun, 2020-11-22 at 10:21 -0800, James Bottomley wrote:
> > > > Please tell me our reward for all this effort isn't a single
> > > > missing error print.
> > > 
> > > There were quite literally dozens of logical defects found
> > > by the fallthrough additions.  Very few were logging only.
> > 
> > So can you give us the best examples (or indeed all of them if
> > someone is keeping score)?  hopefully this isn't a US election
> > situation ...
> 
> Gustavo?  Are you running for congress now?
> 
> https://lwn.net/Articles/794944/

That's 21 reported fixes of which about 50% seem to produce no change
in code behaviour at all, a quarter seem to have no user visible effect
with the remaining quarter producing unexpected errors on obscure
configuration parameters, which is why no-one really noticed them
before.

James