[commit: ghc] ghc-7.8: Further improvements to floating equalities (e9382e3)

[git at git.haskell.org]

Repository : ssh://git@git.haskell.org/ghc

On branch  : ghc-7.8
Link       : http://ghc.haskell.org/trac/ghc/changeset/e9382e3dab2246a33675ffeae31a105d7cf7f426/ghc

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commit e9382e3dab2246a33675ffeae31a105d7cf7f426
Author: Simon Peyton Jones <simonpj at microsoft.com>
Date:   Fri Jul 18 09:35:24 2014 +0100

    Further improvements to floating equalities
    
    This equality-floating stuff is horribly delicate!  Trac #9316 showed
    up yet another corner case.
    
    The main changes are
     * include CTyVarEqs when "growing" the skolem set
     * do not include the kind argument to (~) when growing the skolem set
    
    I added a lot more comments as well
    
    (cherry picked from commit 4b3df0bb705c9287046c07bbc6c038960fbf8d53)


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e9382e3dab2246a33675ffeae31a105d7cf7f426
 compiler/typecheck/TcSimplify.lhs                  | 311 +++++++++++++--------
 .../tests/indexed-types/should_compile/T9316.hs    |  87 ++++++
 testsuite/tests/indexed-types/should_compile/all.T |   1 +
 3 files changed, 279 insertions(+), 120 deletions(-)

Diff suppressed because of size. To see it, use:

    git diff-tree --root --patch-with-stat --no-color --find-copies-harder --ignore-space-at-eol --cc e9382e3dab2246a33675ffeae31a105d7cf7f426