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From: Segher Boessenkool <segher@kernel.crashing.org>
Subject: Re: Saving to 32 bits of GPRs in signal context
Date: Wed, 30 May 2007 14:07:29 +0200
To: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: linuxppc-dev list <linuxppc-dev@ozlabs.org>,
	Steve Munroe <sjmunroe@us.ibm.com>,
	Ulrich Weigand <Ulrich.Weigand@de.ibm.com>,
	Paul Mackerras <paulus@samba.org>, Anton Blanchard <anton@samba.org>
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>> This prctl() is needed if you want to support DSOs containing
>> 64-bit insns.  It would be nice to have some ELF flag as well
>> though, so most of this can be handled automatically.
>
> Actually, it's the opposite... the prctl becomes a problem if you have
> libs wanting to use 64 bits for optims

The host application, or the dynamic loader, can call
the prctl() when it loads the DSO that needs it.

In almost all cases this should all be transparent
for the user IMHO, based on some ELF flag.


Segher