#7372: Lint failure in GHC 7.6.1 -------------------------------+-------------------------------------------- Reporter: simonpj | Owner: Type: bug | Status: closed Priority: normal | Milestone: 7.8.1 Component: Compiler | Version: 7.6.1 Resolution: fixed | Keywords: Os: Unknown/Multiple | Architecture: Unknown/Multiple Failure: None/Unknown | Difficulty: Unknown Testcase: | Blockedby: Blocking: | Related: -------------------------------+-------------------------------------------- Changes (by monoidal): * status: new => closed * resolution: => fixed Comment: I checked it. TL;DR: the same cause as in #7312, fixed in HEAD and STABLE. Here's a small version: {{{ module Main where data Exp = Cte Integer | Let Exp eval :: Exp -> (->) a Integer eval (Cte i) = return i -- (1) eval (Let b) = \m -> eval b m -- (2) main = undefined }}} Under GHC 7.6.1, there are two problems. Both are fixed by changing (->) a Integer to a -> Integer. Line (1) compiles but fails dcore-lint. In fact {{{ c :: (->) a a c = id }}} already fails dcore-lint, saying that the types {{{(->) a a}}} and {{{a -> a}}} do not match. Line (2) gives panic identical to #7312. The code works fine after the fix in #7312. -- Ticket URL: http://hackage.haskell.org/trac/ghc/ticket/7372#comment:2 GHC http://www.haskell.org/ghc/ The Glasgow Haskell Compiler