Subject: Re: [patch 00/2] improve .text size on gcc 4.0 and newer compilers
From: Alan Cox <alan@lxorguk.ukuu.org.uk>
To: Russell King <rmk+lkml@arm.linux.org.uk>
Cc: Arjan van de Ven <arjan@infradead.org>, Krzysztof Halasa <khc@pm.waw.pl>,
       Ingo Molnar <mingo@elte.hu>, Adrian Bunk <bunk@stusta.de>,
       Tim Schmielau <tim@physik3.uni-rostock.de>,
       Linus Torvalds <torvalds@osdl.org>, Dave Jones <davej@redhat.com>,
       Andrew Morton <akpm@osdl.org>, lkml <linux-kernel@vger.kernel.org>,
       mpm@selenic.com
In-Reply-To: <20060102222335.GB5412@flint.arm.linux.org.uk>
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Date: Mon, 02 Jan 2006 23:55:41 +0000
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On Llu, 2006-01-02 at 22:23 +0000, Russell King wrote:
> > you know what? gcc inlines those automatic even without you typing
> > "inline". (esp if you have unit-at-a-time enabled)

> GCC will only automatically inline using -O3.  We don't use -O3 with
> the kernel - only -O2 and -Os.

Or using -finline-functions which is a good idea. -O3 has some other
undesirable side effects. Both -O2 -finline-functions and -Os
-finline-functions will do what looks to be the right thing.

Mind you anything more than a few instructions is questionable with
current processors.

Alan

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