From: Jim Wilson <wilson@specifixinc.com>
To: Ebony Zhu <ebony.zhu@motorola.com>
Cc: gcc@gcc.gnu.org
Subject: Re: optimization issue about -O2 and -Os
Date: Fri, 30 Apr 2004 00:37:00 -0000 [thread overview]
Message-ID: <40918894.6070706@specifixinc.com> (raw)
In-Reply-To: <1083221404.1215.267.camel@Woogie>
Ebony Zhu wrote:
> build some applications such as U-Boot, Busybox..., with the -Os
> optimization, the apps can be built but cannot run (just halted, there
> were even no error messages). If I use -O2 switch then everything is OK.
>
> According to manpage of GCC, -Os is based on -O2 switch and does some
> work to reduce the code size. What GCC did on earth with the -Os switch?
The -Os option is buggy. You might want to report a bug into our
bugzilla bug datase. See
http://gcc.gnu.org/bugs.html
for more info on reporting bugs.
Though the -Os option is based on the -O2 option, it is a different
option, that generates different code, and has different bugs.
--
Jim Wilson, GNU Tools Support, http://www.SpecifixInc.com
next prev parent reply other threads:[~2004-04-29 22:58 UTC|newest]
Thread overview: 14+ messages / expand[flat|nested] mbox.gz Atom feed top
2004-04-29 10:33 Ebony Zhu
2004-04-30 0:37 ` Jim Wilson [this message]
2004-04-30 6:39 ` Ebony Zhu
2004-04-30 9:20 ` Jim Wilson
2004-04-30 13:23 ` Ebony Zhu
2004-04-30 16:06 ` Dave Korn
2004-04-30 16:42 ` Zack Weinberg
2004-04-30 18:09 ` Dave Korn
2004-04-30 19:12 ` Zack Weinberg
2004-04-30 19:45 ` Dave Korn
2004-04-30 20:05 ` Phil Edwards
2004-04-30 20:09 ` David Edelsohn
2004-04-30 21:02 ` llewelly
2004-04-30 18:29 ` Dale Johannesen
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