#14361: GHC HEAD miscompiles `text-containers` -------------------------------------+------------------------------------- Reporter: hvr | Owner: (none) Type: bug | Status: patch Priority: high | Milestone: 8.4.1 Component: Compiler | Version: 8.3 Resolution: | Keywords: Operating System: Unknown/Multiple | Architecture: Type of failure: Incorrect result | Unknown/Multiple at runtime | Test Case: Blocked By: | Blocking: Related Tickets: | Differential Rev(s): Wiki Page: | -------------------------------------+------------------------------------- Comment (by simonpj):
It seems like it would be better to either only pass the constructor and extract the needed values out of it inside the join point, or to only pass the unboxed arguments, and construct the constructor when needed.
It's indeed not clear which is best. It's a conscious choice though; see `Note [Case binders and join points]` in `Simplify.hs`. -- Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/14361#comment:14> GHC <http://www.haskell.org/ghc/> The Glasgow Haskell Compiler