Changes to ghc(5)

Changes to ghc:
commit ff9f9a7f2e227fcda7b8a2f52ec8be66de2e76cd
Author: Simon Peyton Jones <simonpj@microsoft.com>
Date:   Mon Apr 14 13:06:22 2014 +0100

    Test Trac #8985

commit e7f0ae7ff4f2199abe42f20bac825a7802bff466
Author: Simon Peyton Jones <simonpj@microsoft.com>
Date:   Mon Apr 14 13:03:40 2014 +0100

    Honour the untouchability of kind variables

    Trac #8985 showed up a major shortcoming in the kind unifier: it was
    ignoring untoucability.  This has unpredictably-bad consequences;
    notably, the skolem-escape check can fail.

    There were two things wrong
     * TcRnMonad.isTouchableTcM was returning a constant value for kind variables
       (wrong), and even worse the constant was back-to-front (it was always False).

     * We weren't even calling isTouchableTcM in TcType.unifyKindX.

    I'm not sure how this ever worked.

    Merge to 7.8.3 in due course.

commit 14046d0387188a356d0fbc342506ca5ed3001b1c
Author: Simon Peyton Jones <simonpj@microsoft.com>
Date:   Mon Apr 14 12:48:31 2014 +0100

    A bit more trace information in an ASSERT failure

commit bfd00648c0b8527d56974d5af71fd5c149dbc565
Author: Simon Peyton Jones <simonpj@microsoft.com>
Date:   Mon Apr 14 10:01:12 2014 +0100

    Tidy up trace message

commit 70d263ecdcb5d11044c7fab570b70f1bf496a9fd
Author: Simon Peyton Jones <simonpj@microsoft.com>
Date:   Mon Apr 14 09:59:08 2014 +0100

    Better layout for coercion error message