Re: gcc -O2 bug

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#3661

From: Dan Pop
Date: Thu, 08 Aug 1996 00:00

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In <3209b0dc.0@epflnews.epfl.ch> Thomas.Wolf@di.epfl.ch (Thomas Wolf) writes:

>5. How your compiler determined that 'time' does not return something
>   that results in 'flag' == 0 is a mystery to me. Maybe it didn't and
>   this is just its version of undefined behavior?

Nope.  The compiler didn't determine anything about time(), it simply
put the test _before_ the loop and generated an infinite loop.  That is
what any decent optimizing compiler is supposed to do in such a case,
since the expression being tested is a loop invariant.

Dan
--
Dan Pop
CERN, CN Division
Email: Dan.Pop@cern.ch 
Mail:  CERN - PPE, Bat. 31 R-004, CH-1211 Geneve 23, Switzerland

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From: Dan.Pop@cern.ch (Dan Pop)
Subject: Re: gcc -O2 bug
Date: 1996/08/08
Message-ID: <danpop.839521193@news.cern.ch>
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keywords: gcc bug O2
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