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Date: Mon, 29 Nov 2010 12:12:01 +0100 (CET)
Subject: Re: [PATCH] Built kernel without -O2 option
From: "Segher Boessenkool" <segher@kernel.crashing.org>
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To: Christian Borntraeger <borntraeger@de.ibm.com>
Cc: =?iso-8859-1?Q?Am=E9rico_Wang?= <xiyou.wangcong@gmail.com>, Hui Zhu <teawater@gmail.com>, linux-kernel@vger.kernel.org, gdb@sourceware.org, hellogcc@freelists.org, linux-kbuild@vger.kernel.org

> In essence -O2 just tells gcc to activate a list of optimizations
> gcc  -Q -O2 --help=optimizers
> tells you what.

Not quite; see http://gcc.gnu.org/wiki/FAQ#optimization-options .


Segher