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To: Adrian Chadd <adrian@freebsd.org>
Subject: Re: RFC: (Unconditionally) enable -fno-strict-overflow for kernel
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In-reply-to: <CAJ-VmomC6CMuo__etm7X6W8Hpg8MafL2StePdSz4Jn0XN6MGww@mail.gmail.com>
From: "Poul-Henning Kamp" <phk@phk.freebsd.dk>
References: <20131130135616.GA59496@kib.kiev.ua>
 <CAJ-VmomC6CMuo__etm7X6W8Hpg8MafL2StePdSz4Jn0XN6MGww@mail.gmail.com>
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Date: Sat, 30 Nov 2013 21:57:25 +0000
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Cc: Konstantin Belousov <kostikbel@gmail.com>,
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In message <CAJ-VmomC6CMuo__etm7X6W8Hpg8MafL2StePdSz4Jn0XN6MGww@mail.gmail.com>
, Adrian Chadd writes:

>> The compiler authors take the undefined part there as a blanket to perform
>> optimizations which are assuming that signed overflow cannot happen.

That's sufficient explanation for me to support your proposal.

-- 
Poul-Henning Kamp       | UNIX since Zilog Zeus 3.20
phk@FreeBSD.ORG         | TCP/IP since RFC 956
FreeBSD committer       | BSD since 4.3-tahoe    
Never attribute to malice what can adequately be explained by incompetence.