#12130: ghc: panic! (the 'impossible' happened): find_tycon Block [] -------------------------------------+------------------------------------- Reporter: jeiea | Owner: adamgundry Type: bug | Status: closed Priority: high | Milestone: 8.0.2 Component: Template Haskell | Version: 8.0.1 Resolution: fixed | Keywords: | DisambiguateRecordFields Operating System: Unknown/Multiple | Architecture: Type of failure: Compile-time | Unknown/Multiple crash | Test Case: th/T12130 Blocked By: | Blocking: Related Tickets: #11228 | Differential Rev(s): Phab:D2321 Wiki Page: | -------------------------------------+------------------------------------- Comment (by spl): For others who happen upon this problem with GHC 8.0.1, I've used the following workaround. In each module where the error occurs, add ```{-# LANGUAGE NoDisambiguateRecordFields NoRecordWildCards #-}``` and remove all uses of disambiguated fields and record wildcards from that module. -- Ticket URL: http://ghc.haskell.org/trac/ghc/ticket/12130#comment:9 GHC http://www.haskell.org/ghc/ The Glasgow Haskell Compiler