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From: Paul Brook <paul@codesourcery.com>
Subject: Re: [Qemu-devel] 0.9.0 and svn don't build with
	=?iso-8859-1?q?-march=3Dpentium2=09etc=2E=3B__was=3A_Latest_SVN_fails_to?=
	=?iso-8859-1?q?_build_on_Fedora_Core_6?= (same with 0.9.0)
Date: Fri, 23 Mar 2007 15:45:49 +0000
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	<20070323105825.0f2da762@neuling> <4603AA3A.7090101@gmail.com>
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To: qemu-devel@nongnu.org
Cc: Sunil Amitkumar Janki <psychicistnonconformist@gmail.com>

> I do not understand enough of QEMU yet, but I have checked out CVS and
> am reading through its source. When I understand more I hope we can fix
> this long-standing annoyance.

This is GCC PR16185 <http://gcc.gnu.org/PR16185>.
There's no fundamental reason why some options trigger it, and others don't. 
It trigerrs fairly randomly depending on the code generation choices gcc 
happens to make.

The problem is that x86 is chronically short of registers. qemu makes this 
significantly worse by telling gcc it can't use most of them. gcc simply 
isn't designed to work in these extreme situations.

Paul