[commit: ghc] master: Suppress unused warnings for selectors for some derived classes (15fcd9a)

[git at git.haskell.org]

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

On branch  : master
Link       : http://ghc.haskell.org/trac/ghc/changeset/15fcd9adb75b95b32fbe08d066a2ada5f298d667/ghc

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

commit 15fcd9adb75b95b32fbe08d066a2ada5f298d667
Author: Ryan Scott <ryan.gl.scott at gmail.com>
Date:   Tue Jul 11 11:57:05 2017 -0400

    Suppress unused warnings for selectors for some derived classes
    
    Although derived `Read`, `Show`, and `Generic` instances technically
    don't //use// the record selectors of the data type for which an
    instance is being derived, the derived code is affected by the
    //presence// of record selectors. As a result, we should suppress
    `-Wunused-binds` for those record selectors when deriving these classes.
    This is accomplished by threading through more information from
    `hasStockDeriving`.
    
    Test Plan: make test TEST=T13919
    
    Reviewers: austin, bgamari
    
    Reviewed By: bgamari
    
    Subscribers: rwbarton, thomie
    
    GHC Trac Issues: #13919
    
    Differential Revision: https://phabricator.haskell.org/D3704


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15fcd9adb75b95b32fbe08d066a2ada5f298d667
 compiler/typecheck/TcDeriv.hs                      | 39 ++++-----
 compiler/typecheck/TcDerivUtils.hs                 | 92 +++++++++++++++++-----
 testsuite/tests/deriving/should_compile/T13919.hs  | 13 +++
 .../tests/deriving/should_compile/T13919.stderr    |  4 +-
 testsuite/tests/deriving/should_compile/all.T      |  1 +
 5 files changed, 110 insertions(+), 39 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 15fcd9adb75b95b32fbe08d066a2ada5f298d667