#16141: StrictData and TypeFamilies regression -------------------------------------+------------------------------------- Reporter: RyanGlScott | Owner: (none) Type: bug | Status: new Priority: highest | Milestone: 8.8.1 Component: Compiler (Type | Version: 8.6.3 checker) | Resolution: | Keywords: Operating System: Unknown/Multiple | Architecture: Type of failure: GHC rejects | Unknown/Multiple valid program | Test Case: Blocked By: | Blocking: Related Tickets: | Differential Rev(s): Wiki Page: | -------------------------------------+------------------------------------- Comment (by RyanGlScott): The mention of `Int#` has me wondering: is GHC trying to unpack the `Int` field of `MkT`? If so, I would surely think that that's incorrect, since the idea of unpacking a newtype seems bogus, especially since GHC rejects this program: {{{ λ> newtype T = MkT {-# UNPACK #-} !Int <interactive>:1:13: error: • A newtype constructor cannot have a strictness annotation, but ‘MkT’ does • In the definition of data constructor ‘MkT’ In the newtype declaration for ‘T’ }}} Perhaps the implementation of `StrictData` misses this fact, however. I'll check the code to see if that is the case. -- Ticket URL: http://ghc.haskell.org/trac/ghc/ticket/16141#comment:4 GHC http://www.haskell.org/ghc/ The Glasgow Haskell Compiler