#11371: Bogus in-scope set in substitutions -------------------------------------+------------------------------------- Reporter: simonpj | Owner: niteria Type: bug | Status: new Priority: high | Milestone: 8.2.1 Component: Compiler | Version: 7.10.3 Resolution: | Keywords: Operating System: Unknown/Multiple | Architecture: | Unknown/Multiple Type of failure: None/Unknown | Test Case: Blocked By: | Blocking: Related Tickets: #11360 | Differential Rev(s): phab:D1792, Wiki Page: | phab:D1801, phab:D1802 -------------------------------------+------------------------------------- Comment (by simonpj): Well by making it strict you'll certainly force the `tyCoVarsOfTypes` to happen, which isn't really a good idea. But there is something weird here: why is `exprToType` being called on an expression other than `(Type ty)`. Let's find out. You can make the panic print the expr. And it could come from {{{ applyTypeToArg fun_ty arg = piResultTy fun_ty (exprToType arg) }}} perhpas? Which call to `exprToType` (there aren't many) is at fault? More and more mysterious -- Ticket URL: http://ghc.haskell.org/trac/ghc/ticket/11371#comment:38 GHC http://www.haskell.org/ghc/ The Glasgow Haskell Compiler