#13854: the 'impossible' happened initTc: unsolved constraints -------------------------------------+------------------------------------- Reporter: bitemyapp | Owner: (none) Type: bug | Status: closed Priority: normal | Milestone: Component: Compiler | Version: 8.0.2 Resolution: duplicate | Keywords: Operating System: Unknown/Multiple | Architecture: Type of failure: Compile-time | Unknown/Multiple crash or panic | Test Case: Blocked By: | Blocking: Related Tickets: #13106 | Differential Rev(s): Wiki Page: | -------------------------------------+------------------------------------- Changes (by RyanGlScott): * status: new => closed * resolution: => duplicate * related: => #13106 Comment: Thanks for the bug report. This is a duplicate of #13106, which has been fixed in GHC 8.2. Note that this panic is usually caused by using identifiers that aren't in-scope (in your case, `over` and `ix`) in just the right way. -- Ticket URL: http://ghc.haskell.org/trac/ghc/ticket/13854#comment:1 GHC http://www.haskell.org/ghc/ The Glasgow Haskell Compiler