#12788: While using Data.Aeson.TH, "Irrefutable pattern failed for pattern sel_id : _" -------------------------------------+------------------------------------- Reporter: jchia | Owner: Type: bug | Status: new Priority: normal | Milestone: Component: Compiler | Version: 8.0.1 Resolution: | Keywords: Operating System: Unknown/Multiple | Architecture: | Unknown/Multiple Type of failure: None/Unknown | Test Case: Blocked By: | Blocking: Related Tickets: | Differential Rev(s): Wiki Page: | -------------------------------------+------------------------------------- @@ -3,1 +3,1 @@ - + {{{ @@ -15,0 +15,1 @@ + }}} New description: I got the following error compiling simple source file Bad.hs. The bug is likely related to TH as the crash vanishes without the TH line. {{{ $ stack ghc -- -c Bad.hs Run from outside a project, using implicit global project config Using resolver: lts-7.5 from implicit global project's config file: /home/jchia/.stack/global-project/stack.yaml ghc: panic! (the 'impossible' happened) (GHC version 8.0.1 for x86_64-unknown-linux): compiler/typecheck/TcExpr.hs:798:15-35: Irrefutable pattern failed for pattern sel_id : _ Please report this as a GHC bug: http://www.haskell.org/ghc/reportabug }}} -- Comment (by simonpj): Thank you Ryan! -- Ticket URL: http://ghc.haskell.org/trac/ghc/ticket/12788#comment:3 GHC http://www.haskell.org/ghc/ The Glasgow Haskell Compiler