#14777: panic when using a function defined in terms of `error` -------------------------------------+------------------------------------- Reporter: zilinc | Owner: (none) Type: bug | Status: new Priority: normal | Milestone: Component: Compiler | Version: 8.2.2 Resolution: | Keywords: Operating System: Linux | Architecture: Type of failure: Compile-time | Unknown/Multiple crash or panic | Test Case: Blocked By: | Blocking: Related Tickets: | Differential Rev(s): Wiki Page: | -------------------------------------+------------------------------------- Comment (by sighingnow): I have create a self-contained minimal case (still have several files but only depends on base, mtl and containers) that can trigger this panic. I **can** reproduce this panic with ghc-8.2.1 (nightly-2017-11-24) and ghc-8.2.2 (lts-10.3/lts-10.4) but **cannot** with ghc-8.4.1 and ghc-head. Maybe it has already been fixed. I also have test with with ghc-8.0.1 (lts-9.4) but also failed to trigger the panic with this minimal case. Step to reproduce with ghc-8.2.2: unzip and enter `src`, then {{{ stack exec --resolver=lts-10.4 -- ghc Cogent.Desugar -fforce-recomp -O2 }}} -- Ticket URL: http://ghc.haskell.org/trac/ghc/ticket/14777#comment:14 GHC http://www.haskell.org/ghc/ The Glasgow Haskell Compiler