From mboxrd@z Thu Jan  1 00:00:00 1970
From: Linus Torvalds <torvalds@linux-foundation.org>
Subject: Re: gcc inlining heuristics was Re: [PATCH -v7][RFC]: mutex: implement
 adaptive spinning
Date: Sun, 11 Jan 2009 16:21:03 -0800 (PST)
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Cc: David Woodhouse <dwmw2@infradead.org>,
	Andrew Morton <akpm@linux-foundation.org>,
	Ingo Molnar <mingo@elte.hu>,
	Harvey Harrison <harvey.harrison@gmail.com>,
	"H. Peter Anvin" <hpa@zytor.com>,
	Chris Mason <chris.mason@oracle.com>,
	Peter Zijlstra <peterz@infradead.org>,
	Steven Rostedt <rostedt@goodmis.org>,
	paulmck@linux.vnet.ibm.com, Gregory Haskins <ghaskins@novell.com>,
	Matthew Wilcox <matthew@wil.cx>,
	Linux Kernel Mailing List <linux-kernel@vger.kernel.org>,
	linux-fsdevel <linux-fsdevel@vger.kernel.org>,
	linux-btrfs <linux-btrfs@vger.kernel.org>,
	Thomas Gleixner <tglx@linutronix.de>,
	Nick Piggin <npiggin@suse.de>,
	Peter Morreale <pmorreale@novell.com>,
	Sven Dietrich <SDietrich@novell.com>, jh@suse.cz
To: Andi Kleen <andi@firstfloor.org>
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In-Reply-To: <20090112001255.GR26290@one.firstfloor.org>
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On Mon, 12 Jan 2009, Andi Kleen wrote:
> 
> so at least least for this case it works. Your case also doesn't work 
> for me. So it looks like gcc didn't like something you did in your test 
> program.

I very intentionally used _different_ types.

If you use the same type, gcc will apparenrly happily say "hey, I can 
combine two variables of the same type with different liveness into the 
same variable".

But that's not the interesting case.

			Linus