[llvmlinux] [i586] Boot issues

Ghitulete Razvan razvan.ghitulete at gmail.com
Tue Oct 29 20:59:38 UTC 2013

On Mon, Oct 28, 2013 at 9:08 PM, Behan Webster
<behanw at converseincode.com> wrote:
> Whoops. Sorry I didn't reply earlier.
No problem :)

> I'm not sure I've heard of anyone else having this issue.  Certainly
> this is a big deal if it's happening to others as well.
> I'd certainly like to know why this happened.
As far as I can tell, this was caused due to the fact that an
assignment is eventually transformed into a memcpy, which gets linked
in the end with the one from arch/x86/lib. The problem, as noticed
from the generated assembly was that this implicit calls had a
signature for the memcpy with regparm(0) while in arch/x86/lib it is
defined without. GCC doesn't run into this issues because it inlines
the memcpy when it reaches structure assignments.

I might have hit this issue because I modified some additional headers
from the kernel in order to get it compile on my particular config,
and I meddled a little with the memcpy myself, but I didn't alter any

Razvan Ghitulete

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