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Date: Wed, 17 Oct 2007 15:00:17 +0100
From: Andrew Haley <aph@redhat.com>
To: Jakub Jelinek <jakub@redhat.com>
Subject: Re: [PATCH] powerpc: Fix 64 bits vDSO dwarf info for CR register
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	<20071017135055.GP5451@devserv.devel.redhat.com>
Cc: Deepak Bhole <dbhole@redhat.com>,
	linuxppc-dev list <linuxppc-dev@ozlabs.org>,
	Benjamin Herrenschmidt <benh@au1.ibm.com>,
	Paul Mackerras <paulus@samba.org>, Alan Modra <amodra@bigpond.net.au>
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Jakub Jelinek writes:
 > On Wed, Oct 17, 2007 at 02:26:50PM +1000, Benjamin Herrenschmidt wrote:
 > > Unfortunately, a bug in gcc cause it to not quite work either, but that
 > > is being fixed separately with something around the lines of:
 > > 
 > > linux-unwind.h:
 > > 
 > >      fs->regs.reg[R_CR2].loc.offset = (long) &regs->ccr - new_cfa;
 > > +    /* CR? regs are just 32-bit and PPC is big-endian.  */
 > > +    fs->regs.reg[R_CR2].loc.offset += sizeof (long) - 4;
 > 
 > Small correction.  If vdso is present, then fixing the vdso is all that is
 > needed, the above mentioned code is used only if the vdso is not present
 > (or if glibc doesn't support the vdso).

Perhaps we should test this change with a hacked libgcc, just to make
sure it fixes the bug.

Andrew.

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