[commit: ghc] ghc-8.0: Update 8.0.2 release notes for #12784 (2591a4b)

[git at git.haskell.org]

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

On branch  : ghc-8.0
Link       : http://ghc.haskell.org/trac/ghc/changeset/2591a4b94903d4f9d9348a92599a74aacf5eda66/ghc

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

commit 2591a4b94903d4f9d9348a92599a74aacf5eda66
Author: Ryan Scott <ryan.gl.scott at gmail.com>
Date:   Mon Nov 7 08:56:22 2016 -0500

    Update 8.0.2 release notes for #12784
    
    Summary:
    The fix for #12220 exposed some ill-typed programs which passed the typechecker
    in GHC 8.0.1 but now fail to typecheck in GHC 8.0.2. It's a bit difficult to
    characterize what exactly triggers this bug, but we at least have a minimal
    example and a simple fix to illustrate the problem and solution, so let's
    add that the the 8.0.2 release notes to advertise this change.
    
    Resolves #12784.
    
    Reviewers: rwbarton, austin, bgamari
    
    Reviewed By: bgamari
    
    Subscribers: thomie
    
    Differential Revision: https://phabricator.haskell.org/D2682
    
    GHC Trac Issues: #12784
    
    (cherry picked from commit 2e8463b232054b788b73e6551947a9434aa76009)


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

2591a4b94903d4f9d9348a92599a74aacf5eda66
 docs/users_guide/8.0.2-notes.rst | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/docs/users_guide/8.0.2-notes.rst b/docs/users_guide/8.0.2-notes.rst
index b1568ae..2986e38 100644
--- a/docs/users_guide/8.0.2-notes.rst
+++ b/docs/users_guide/8.0.2-notes.rst
@@ -25,6 +25,10 @@ Language
    presence of :ghc-flag:`-XRebindableSyntax` and
    :ghc-flag:`-XOverloadedStrings` (:ghc-ticket:`12688`).
 
+-  Some programs using :ghc-flag:`-XDefaultSignatures` that incorrectly
+   type-checked in GHC 8.0.1 are now rejected by GHC 8.0.2. See
+   :ghc-ticket:`12784` for details.
+
 Compiler
 ~~~~~~~~