#9732: Pattern synonyms and unboxed values -------------------------------------+------------------------------------- Reporter: monoidal | Owner: cactus Type: bug | Status: new Priority: normal | Milestone: Component: Compiler | Version: 7.8.3 Resolution: | Keywords: Operating System: | Architecture: Unknown/Multiple Unknown/Multiple | Difficulty: Unknown Type of failure: Compile- | Blocked By: time crash | Related Tickets: Test Case: | Blocking: | Differential Revisions: | -------------------------------------+------------------------------------- Comment (by cactus): As for the unidirectional case, I was accidentally looking at the simplified output instead of just the desugared one. So with this code: {{{ {-# LANGUAGE PatternSynonyms, MagicHash #-} pattern PAT <- 0# f PAT = 42# }}} the Core generated for `f` is: {{{ Main.f :: GHC.Prim.Int# -> GHC.Prim.Int# [LclIdX, Str=DmdType] Main.f = \ (ds_dpR :: GHC.Prim.Int#) -> break<2>() case (\ _ [Occ=Dead, OS=OneShot] -> Control.Exception.Base.patError @ GHC.Prim.Int# "T9732.hs:7:1-11|function f"#) GHC.Prim.void# of wild_00 { __DEFAULT -> (case break<1>() 42 of wild_X4 { __DEFAULT -> Main.$mPAT @ GHC.Prim.Int# ds_dpR wild_X4 }) wild_00 } }}} which is close enough: it would be correct if only `wild_00` wasn't floated out... -- Ticket URL: http://ghc.haskell.org/trac/ghc/ticket/9732#comment:9 GHC http://www.haskell.org/ghc/ The Glasgow Haskell Compiler