#8762: Panic involving unboxed tuples and phantom types -------------------------------------+------------------------------------ Reporter: josef | Owner: Type: bug | Status: new Priority: normal | Milestone: 7.8.1 Component: Compiler | Version: 7.8.1-rc1 Resolution: | Keywords: Operating System: Unknown/Multiple | Architecture: Unknown/Multiple Type of failure: None/Unknown | Difficulty: Unknown Test Case: | Blocked By: Blocking: | Related Tickets: -------------------------------------+------------------------------------ Comment (by goldfire): I just took a look at this and ended up in deeper waters within the type- checker than where I feel comfortable. But I did discover that the bug persists with {{{ {-# LANGUAGE UnboxedTuples #-} module Bug where data Ty a = Int bug :: () -> (# Ty a, () #) bug _ = (# Int, () #) main :: IO () main = do let (# a, b #) = bug () return () }}} Note that there is no `undefined`, and the previous type synonym `Ty` has now become a datatype. -- Ticket URL: http://ghc.haskell.org/trac/ghc/ticket/8762#comment:3 GHC http://www.haskell.org/ghc/ The Glasgow Haskell Compiler