Changes to ghc

Changes to ghc:
commit a6939ec29a9238cee38bee20844ae8cdcd4952fd
Author: Johan Tibell <johan.tibell@gmail.com>
Date:   Thu Mar 20 07:58:10 2014 +0100

    Don't use gcptr for interior pointers

    gcptr should only be used for pointers that the GC should
    follow. While this didn't cause any bugs right now, since these
    variables aren't live over a GC, it's clearer to use the right type.