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From: Frank Peters <frank.peters@comcast.net>
To: gentoo-amd64@lists.gentoo.org
Subject: Re: [gentoo-amd64] Re: GCC-4.5.2 Has Serious Problems
Date: Thu, 30 Jun 2011 21:23:21 -0400	[thread overview]
Message-ID: <20110630212321.ad403843.frank.peters@comcast.net> (raw)
In-Reply-To: <pan.2011.07.01.00.58.46@cox.net>

On Fri, 1 Jul 2011 00:58:46 +0000 (UTC)
Duncan <1i5t5.duncan@cox.net> wrote:

> 
> I had wondered if this might be an "undefined behavior" optimization bug, 
>  

Well, the amd64 users list may not be the appropriate place to discuss
C programming, but the problem here stems from attempting to do things
with C that are not supposed to be done with C.  Such things are aptly
called "tricks" because they stray away from the convention.

Ideally, I suppose, for these purposes would be to use assembly language
routines mixed into the C code.  But this is not as easy as with the
"tricks."

Anyway, I'm glad I presented this issue.  It has definitely improved
my understanding.  GCC has dozens, if not hundreds, of compile options
and I know the actual function of only a small few.

Frank Peters



  reply	other threads:[~2011-07-01  1:24 UTC|newest]

Thread overview: 21+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2011-06-30 21:45 [gentoo-amd64] GCC-4.5.2 Has Serious Problems Frank Peters
2011-06-30 22:30 ` Alex Schuster
2011-06-30 23:34   ` Frank Peters
2011-06-30 23:35 ` [gentoo-amd64] " Nikos Chantziaras
2011-06-30 23:44   ` Nikos Chantziaras
2011-07-01  0:04     ` Frank Peters
2011-07-01  0:11       ` Nikos Chantziaras
2011-07-01  0:58         ` Duncan
2011-07-01  1:23           ` Frank Peters [this message]
2011-07-01  1:52             ` Duncan
2011-07-01  2:15             ` Ian McCulloch
2011-07-01  4:36             ` Mark Knecht
2011-07-01  5:22               ` Frank Peters
2011-07-01  0:25     ` Frank Peters
2011-07-01  1:04     ` Frank Peters
2011-07-01  2:18       ` Duncan
2011-07-01  2:22       ` Barry Schwartz
2011-07-01  2:43         ` Frank Peters
2011-07-01 11:53       ` Nikos Chantziaras
2011-07-01 16:53         ` Frank Peters
  -- strict thread matches above, loose matches on Subject: below --
2011-07-01  2:30 Ian McCulloch

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