maybe you can try `pacman -Syyup --debug`
`p' to print out the uris but not download or install anything

i can't test it since i'm fully updated,
but you could also try the `w' to just download the pkgs instead of `p'
i couldn't see anything in the pacman -h about doing that
so i guess we could just look in the debugging output
if that doesn't quite help

On Thu, Oct 23, 2008 at 6:22 PM, Louis Brazeau <lbrazeau@gmail.com> wrote:
On Thu, Oct 23, 2008 at 1:05 PM, Raeven K.Bathory <kumyco@nrk.cc> wrote:
> what happens if you remove the possibly corrupted cached file
> /var/cache/pacman/pkg/xextproto-7.0.3-2-x86_64.pkg.tar.gz
>

The line :

 debug: setting download size 0 for pkg xextproto

changes to :

 debug: setting download size 41286 for pkg xextproto

but the error message remains.

So the problem package must be the next one to be checked. Is there a
way to see the list of package that pacman -Syu is checking?