[commit: ghc] ghc-8.6: Fix #15415 and simplify tcWildCardBinders (a97ead7)

[git at git.haskell.org]

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

On branch  : ghc-8.6
Link       : http://ghc.haskell.org/trac/ghc/changeset/a97ead78b76bfd914adb7c5b331ee364fc6f1928/ghc

>---------------------------------------------------------------

commit a97ead78b76bfd914adb7c5b331ee364fc6f1928
Author: Vladislav Zavialov <vlad.z.4096 at gmail.com>
Date:   Wed Aug 1 14:28:16 2018 -0400

    Fix #15415 and simplify tcWildCardBinders
    
    Test Plan: Validate
    
    Reviewers: goldfire, simonpj, bgamari
    
    Reviewed By: simonpj
    
    Subscribers: RyanGlScott, rwbarton, thomie, carter
    
    GHC Trac Issues: #15415
    
    Differential Revision: https://phabricator.haskell.org/D5022
    
    (cherry picked from commit 120cc9f85ee1120072eb44c5bf37ac3055883605)


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a97ead78b76bfd914adb7c5b331ee364fc6f1928
 compiler/typecheck/TcHsType.hs                     | 32 ++++++----------------
 compiler/typecheck/TcRnDriver.hs                   |  9 ++++--
 .../should_run/GHCiWildcardKind.script             |  1 +
 .../tests/partial-sigs/should_run/T15415.script    | 17 ++++++++++++
 .../tests/partial-sigs/should_run/T15415.stderr    | 27 ++++++++++++++++++
 .../tests/partial-sigs/should_run/T15415.stdout    |  6 ++++
 testsuite/tests/partial-sigs/should_run/all.T      |  1 +
 testsuite/tests/unboxedsums/T12711.script          |  2 +-
 8 files changed, 67 insertions(+), 28 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 a97ead78b76bfd914adb7c5b331ee364fc6f1928