From mboxrd@z Thu Jan  1 00:00:00 1970
From: Haavard Skinnemoen <haavard.skinnemoen@atmel.com>
Date: Fri, 25 Jul 2008 11:16:10 +0200
Subject: [U-Boot-Users] Changing u-boot relocation scheme
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On Thu, 24 Jul 2008 19:12:20 +0200
Kenneth Johansson <kenneth@southpole.se> wrote:

> > We could build u-boot as a shared library I guess, but that feels a bit
> > weird...  
> 
> What do you mean by that ? u-boot is already compiled with the -fPIC
> option. 

If that's sufficient, why would you need the -mrelocatable option on
PowerPC?

-fPIC makes the compiler generate position-independent code, which is
necessary but not sufficient in order to get a fully relocatable
binary. The second part of the puzzle is dynamic relocations. Shared
libraries have them, and apparently, PowerPC binaries have them if you
link with -mrelocatable.

Currently u-boot is compiled with -fPIC, so the result is almost fully
relocatable. We work around the lack of dynamic relocations by manually
fixing up a handful of pointers at runtime.

Haavard