diff options
Diffstat (limited to 'compiler/GHC/Core/Opt/Arity.hs')
| -rw-r--r-- | compiler/GHC/Core/Opt/Arity.hs | 11 |
1 files changed, 9 insertions, 2 deletions
diff --git a/compiler/GHC/Core/Opt/Arity.hs b/compiler/GHC/Core/Opt/Arity.hs index 5ed015281a..cd0463961e 100644 --- a/compiler/GHC/Core/Opt/Arity.hs +++ b/compiler/GHC/Core/Opt/Arity.hs @@ -3088,8 +3088,15 @@ etaExpandToJoinPointRule join_arity rule@(Rule { ru_bndrs = bndrs, ru_rhs = rhs | need_args < 0 = pprPanic "etaExpandToJoinPointRule" (ppr join_arity $$ ppr rule) | otherwise - = rule { ru_bndrs = bndrs ++ new_bndrs, ru_args = args ++ new_args - , ru_rhs = new_rhs } + = rule { ru_bndrs = bndrs ++ new_bndrs + , ru_args = args ++ new_args + , ru_rhs = new_rhs } + -- new_rhs really ought to be occ-analysed (see GHC.Core Note + -- [OccInfo in unfoldings and rules]), but it makes a module loop to + -- do so; it doesn't happen often; and it doesn't really matter if + -- the outer binders have bogus occurrence info; and new_rhs won't + -- have dead code if rhs didn't. + where need_args = join_arity - length args (new_bndrs, new_rhs) = etaBodyForJoinPoint need_args rhs |