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From: "acahalan at gmail dot com" <gcc-bugzilla@gcc.gnu.org>
To: gcc-bugs@gcc.gnu.org
Subject: [Bug middle-end/30075] Missed optimizations with -fwhole-program -combine
Date: Tue, 26 Jun 2007 03:10:00 -0000	[thread overview]
Message-ID: <20070626031026.16205.qmail@sourceware.org> (raw)
In-Reply-To: <bug-30075-13698@http.gcc.gnu.org/bugzilla/>



------- Comment #4 from acahalan at gmail dot com  2007-06-26 03:10 -------
(In reply to comment #3)
> Subject: Re:  Missed optimizations with -fwhole-program -combine
> 
> I would not expect this to be fixed anytime soon.  I have yet to find
> any real people who use either combine or -fwhole-program.  They use
> *way* too much memory on real programs.  As a result, no real people
> involved in optimization work on optimizers for them.

I'm real, and I want to use those.

I can't use them because of bug #29171. They appear to be 100% unusable for
non-trivial programs because gcc WILL emit calls to memcpy and there isn't any
possible (documented at least) way to provide a memcpy. No matter how I
__attribute__ my memcpy, and no matter if I use -ffreestanding or not, gcc
wants to call an extern memcpy. Linking against a libc is against the
documented requirements for using these options.


-- 

acahalan at gmail dot com changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
                 CC|                            |acahalan at gmail dot com


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=30075


  parent reply	other threads:[~2007-06-26  3:10 UTC|newest]

Thread overview: 10+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2006-12-05 18:43 [Bug c/30075] New: " ajax at redhat dot com
2006-12-05 18:47 ` [Bug middle-end/30075] Missed optimizations with static variable and static function pinskia at gcc dot gnu dot org
2006-12-05 19:37 ` [Bug c/30075] Missed optimizations with -fwhole-program -combine ajax at redhat dot com
2006-12-05 19:39 ` [Bug middle-end/30075] " pinskia at gcc dot gnu dot org
2006-12-06  2:55   ` Daniel Berlin
2006-12-06  2:55 ` dberlin at dberlin dot org
2007-06-26  3:10 ` acahalan at gmail dot com [this message]
2007-06-26 15:29   ` Daniel Berlin
2007-06-26 15:29 ` dberlin at dberlin dot org
2010-09-17  9:09 ` rguenth at gcc dot gnu dot org

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