[U-Boot] ARM relocation, question to Heiko

Wolfgang Denk
2010-10-03T18:43:06Z

Dear "J. William Campbell",

In message <4CA8A2E0.7090407@comcast.net> you wrote:
>
> executable instructions than programs compiled without these options.
> The program will also contain more data space for the got. If -fPIC
> actually produced a fully position-independent executable, the extra
> overhead would perhaps be tolerable. However, since it does not do this,
> (problems with initialized data etc.) there is really no advantage in
> using these compile-time options. The executable code and required data
> space for the program without these switches will "always" be smaller
> and faster than with them. In order to fix the remaining issues even
> when using -fPIC, a relocation loop must exist in the u-boot code,
> either one global one or a bunch of user written specific ones. Also,

If needed, we should have a global one only.

> It will be interesting to see what the results of this comparison
> are. For me, the no user awareness of relocation is worth a lot, and the
> fact that the difference/overhead of relocation will all be in exactly
> one place is very appealing.

Agreed.

Best regards,

Wolfgang Denk

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