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From: Keith Thompson <kst-u@mib.org>
Newsgroups: comp.lang.c
Subject: Re: The bug
Date: Tue, 13 Feb 2018 11:44:13 -0800
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jacobnavia <jacob@jacob.remcomp.fr> writes:
> Le 08/02/2018 à 22:50, jacobnavia a écrit :
>> Consider this program:
[snip]
>> Compiled without any optimizations, this program outputs nothing. Gcc 
>> with -O2 will print "bug".
>> 
>> Why is this happening?
>> 
>
> I found the root cause: gcc/clang will assume that there is no "UB" i.e. 
> no overflow. Then, a multiplication of two unsigned values into a signed 
> result can't be negative.

*You* found the root cause?  I posted the explanation last Thursday.

If you've killfiled me, you're free to do so, but I'd like to know about
it so I don't waste my time.

Can someone post a followup to this so jacob sees it?  I'll also mention
that I recently posted an lcc-win bug report in comp.compilers.lcc;
jacob might have missed that as well.

-- 
Keith Thompson (The_Other_Keith) kst-u@mib.org  <http://www.ghoti.net/~kst>
Working, but not speaking, for JetHead Development, Inc.
"We must do something.  This is something.  Therefore, we must do this."
    -- Antony Jay and Jonathan Lynn, "Yes Minister"