[commit: ghc] master: Take account of injectivity when doing fundeps (2cdd9bd)

[git at git.haskell.org]

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

On branch  : master
Link       : http://ghc.haskell.org/trac/ghc/changeset/2cdd9bd5208e3ad78d7a3b8b82c8ae1be486b34d/ghc

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

commit 2cdd9bd5208e3ad78d7a3b8b82c8ae1be486b34d
Author: Simon Peyton Jones <simonpj at microsoft.com>
Date:   Fri Nov 4 10:43:36 2016 +0000

    Take account of injectivity when doing fundeps
    
    This fixes Trac #12803. Yikes!
    
    See Note [Care with type functions].


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2cdd9bd5208e3ad78d7a3b8b82c8ae1be486b34d
 compiler/prelude/TysWiredIn.hs                     |  5 ++
 compiler/typecheck/FamInst.hs                      | 62 ++++++++++++----------
 compiler/typecheck/FunDeps.hs                      | 39 ++++++++++++--
 compiler/types/Class.hs                            |  2 +-
 testsuite/tests/typecheck/should_fail/T12803.hs    | 10 ++++
 .../tests/typecheck/should_fail/T12803.stderr      |  8 +++
 testsuite/tests/typecheck/should_fail/all.T        |  1 +
 7 files changed, 94 insertions(+), 33 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 2cdd9bd5208e3ad78d7a3b8b82c8ae1be486b34d