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Date:   Tue, 24 Nov 2020 13:48:34 +1100 (AEDT)
From:   Finn Thain <fthain@telegraphics.com.au>
To:     Joe Perches <joe@perches.com>
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Subject: Re: [PATCH 000/141] Fix fall-through warnings for Clang
In-Reply-To: <e72a1aaef8673553a3ee9dfa033d6e893e00abcd.camel@perches.com>
Message-ID: <alpine.LNX.2.23.453.2011241210310.7@nippy.intranet>
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>
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On Mon, 23 Nov 2020, Joe Perches wrote:

> On Tue, 2020-11-24 at 11:58 +1100, Finn Thain wrote:
> > it's not for me to prove that such patches don't affect code 
> > generation. That's for the patch author and (unfortunately) for 
> > reviewers.
> 
> Ideally, that proof would be provided by the compilation system itself 
> and not patch authors nor reviewers nor maintainers.
> 
> Unfortunately gcc does not guarantee repeatability or deterministic 
> output. To my knowledge, neither does clang.
> 

Yes, I've said the same thing myself. But having attempted it, I now think 
this is a hard problem. YMMV.

https://lore.kernel.org/linux-scsi/alpine.LNX.2.22.394.2004281017310.12@nippy.intranet/
https://lore.kernel.org/linux-scsi/alpine.LNX.2.22.394.2005211358460.8@nippy.intranet/