[commit: ghc] master: Fix Trac #10004: head [] exception when using recursive mdo (43636e1)

[git at git.haskell.org]

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

On branch  : master
Link       : http://ghc.haskell.org/trac/ghc/changeset/43636e1b8cf4a6d4752a22b098a9edd0759a7600/ghc

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commit 43636e1b8cf4a6d4752a22b098a9edd0759a7600
Author: Simon Peyton Jones <simonpj at microsoft.com>
Date:   Fri Feb 6 16:38:52 2015 +0000

    Fix Trac #10004: head [] exception when using recursive mdo


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43636e1b8cf4a6d4752a22b098a9edd0759a7600
 compiler/rename/RnExpr.hs                    | 53 +++++++++++++++-------------
 testsuite/tests/mdo/should_compile/T10004.hs |  6 ++++
 testsuite/tests/mdo/should_compile/all.T     |  2 ++
 3 files changed, 37 insertions(+), 24 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 43636e1b8cf4a6d4752a22b098a9edd0759a7600