[commit: ghc] : Fix long-standing bug in zipBracketeds, exposed by eager value splitting (6f08f8b)

Repository : ssh://darcs.haskell.org//srv/darcs/ghc

On branch  : 

http://hackage.haskell.org/trac/ghc/changeset/6f08f8bd2111d2e78a40e66d12fe3f42243d1dc4

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

commit 6f08f8bd2111d2e78a40e66d12fe3f42243d1dc4
Author: Max Bolingbroke <[email protected]>
Date:   Tue Jan 3 16:42:45 2012 +0000

    Fix long-standing bug in zipBracketeds, exposed by eager value splitting

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

 compiler/supercompile/Supercompile/Drive/Split.hs |    2 +-
 1 files changed, 1 insertions(+), 1 deletions(-)

diff --git a/compiler/supercompile/Supercompile/Drive/Split.hs b/compiler/supercompile/Supercompile/Drive/Split.hs
index b8f494d..dc609a7 100644
--- a/compiler/supercompile/Supercompile/Drive/Split.hs
+++ b/compiler/supercompile/Supercompile/Drive/Split.hs
@@ -455,7 +455,7 @@ zipBracketeds (TailsKnown bty mk_bshell bholes) = case ei_holes of
                 \ty -> shell_extra_fvs ty `unionVarSet` nonRecBindersFreeVars bvs (bracketedExtraFvs rbracketed),
                 \ty es rev_es' -> case splitBy (bracketedHoles rbracketed) es of
                                     (es_here, es_later) -> shell_wrapper ty es_later (shellWrapper (bracketedShell rbracketed) es_here:rev_es'),
-                case ei_holes of Left holes -> Left (holes ++ bracketedHoles rbracketed)
+                case ei_holes of Left holes -> Left (bracketedHoles rbracketed ++ holes)
                                  Right holes | is_tail   -> Left (bracketedHoles rbracketed ++ map tailishHole holes)
                                              | otherwise -> Right (map (TailishHole False) (bracketedHoles rbracketed) ++ holes))
             where rbracketed = rigidizeBracketed bracketed