#13977: ExnStr doesn't propagate "outwards" -------------------------------------+------------------------------------- Reporter: bgamari | Owner: (none) Type: bug | Status: new Priority: normal | Milestone: Component: Compiler | Version: 8.0.1 Resolution: | Keywords: Operating System: Unknown/Multiple | Architecture: | Unknown/Multiple Type of failure: None/Unknown | Test Case: Blocked By: | Blocking: Related Tickets: | Differential Rev(s): Wiki Page: | -------------------------------------+------------------------------------- Comment (by bgamari): {{{#!patch diff --git a/compiler/basicTypes/Demand.hs b/compiler/basicTypes/Demand.hs index 95c7b79b4f..d777da63f0 100644 --- a/compiler/basicTypes/Demand.hs +++ b/compiler/basicTypes/Demand.hs @@ -1442,7 +1442,8 @@ postProcessDmdResult _ res = res postProcessDmdEnv :: DmdShell -> DmdEnv -> DmdEnv postProcessDmdEnv ds@(JD { sd = ss, ud = us }) env | Abs <- us = emptyDmdEnv - | Str _ _ <- ss + | Str VanStr _ <- ss -- Make sure we don't throw about ExnStrs. + -- See #13977. , Use One _ <- us = env -- Shell is a no-op | otherwise = mapVarEnv (postProcessDmd ds) env -- For the Absent case just discard all usage information }}} -- Ticket URL: http://ghc.haskell.org/trac/ghc/ticket/13977#comment:5 GHC http://www.haskell.org/ghc/ The Glasgow Haskell Compiler