After building a fresh tree with gcc 4 I can't boot the simulator as
the bootloader loader dies with 

loading /home/ianw/kerntest/kerncomp//build/sim_defconfig/vmlinux...
failed to read phdr

After some investigation I believe this is do with differences between
the alignment of variables on the stack between gcc 3 and 4 and the
ski simulator.  If you trace through with the simulator you can see
that the disk_stat structure value returned from the SSC_WAIT_COMPLETION
call seems to be only half loaded.  I guess it doesn't like the alignment
of the input.
Signed-off-by: Ian Wienand <ianw@gelato.unsw.edu.au>
Signed-off-by: Tony Luck <tony.luck@intel.com>