#15226: GHC doesn't know that seq# produces something in WHNF -------------------------------------+------------------------------------- Reporter: dfeuer | Owner: (none) Type: bug | Status: merge Priority: normal | Milestone: 8.6.1 Component: Compiler | Version: 8.4.3 Resolution: | Keywords: Operating System: Unknown/Multiple | Architecture: Type of failure: Runtime | Unknown/Multiple performance bug | Test Case: Blocked By: | Blocking: Related Tickets: | Differential Rev(s): Phab:D4796 Wiki Page: | -------------------------------------+------------------------------------- Comment (by dfeuer): The key `OccAnal` functions involved seem to be `mkAltEnv` (not sure what this does, but it seems to look for `Var`s when I want to look also for applications of `seq#`) and `wrapAltRHS` (which seems to actually install the `Let` when appropriate), but I don't see how it all fits together. -- Ticket URL: http://ghc.haskell.org/trac/ghc/ticket/15226#comment:10 GHC http://www.haskell.org/ghc/ The Glasgow Haskell Compiler