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From: Denys Vlasenko <vda.linux@googlemail.com>
To: Sam Ravnborg <sam@ravnborg.org>
Subject: Re: Testing of function/data-sections on linux-2.6.35-rc4
Date: Mon, 26 Jul 2010 03:31:34 +0200
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Hi Sam,

On Friday 23 July 2010 22:35, Sam Ravnborg wrote:
> > 
> > Then, in order to also garbage-collect the sections, I added
> > 
> > LDFLAGS_vmlinux += --gc-sections
> > 
> > in top-level Makefile.
> > 
> > This requires the additional patch (linux-2.6.35-rc4-fsgs.patch)
> > which adds KEEP(section) directives to kernel linker stripts.
> > Otherwise, linker will discard some crucial sections.
> > 
> 
> Changelog does not address why you need:
> 
>      -Map $@.ldmap
> 
> and what effect they have.

I didn't plan to push the last step (--gc-sections) to mainline yet.
Thus the patch has debugging stuff in it.


> And it is obvious that some archs should consolidate a little more from
> asm-generic/vmlinux.lds.h.
> But that said this patch looks much better than the initial versions posted.
> 
> How do you determine which sections needs the KEEP()?
> Worth documenting for future when we add new sections.

No problem, I will be adding comments at every KEEP() why it's needed.

-- 
vda