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Date: Thu, 12 Jun 2008 11:38:19 +1000
From: Paul Mackerras <paulus@samba.org>
To: Ingo Molnar <mingo@elte.hu>
Subject: Re: linux-next: powerpc build failure
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Cc: Stephen Rothwell <sfr@canb.auug.org.au>, linuxppc-dev@ozlabs.org,
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Ingo Molnar writes:

> could this be a tool chain limitation perhaps, or a gcc bug? Or does the 
> allyesconfig size go beyond some fundamental hardware limitation. (i 
> doubt it's the latter)

Direct unconditional branches, including procedure calls, can only
reach +/- 32MB from the address of the branch on powerpc.  So if the
image grows to more than 32MB of text there is a problem unless the
linker is smart enough to insert trampolines.  I don't know whether
GNU ld is that smart.  I'm cc'ing Alan Modra who would know the answer
to that.

Paul.