#10642: Coercible regression from 7.10 to HEAD -------------------------------------+------------------------------------- Reporter: darchon | Owner: goldfire Type: bug | Status: closed Priority: highest | Milestone: 7.12.1 Component: Compiler | Version: 7.11 Resolution: fixed | Keywords: Operating System: Unknown/Multiple | Architecture: Type of failure: GHC rejects | Unknown/Multiple valid program | Test Case: Blocked By: | typecheck/should_compile/T10642 Related Tickets: | Blocking: | Differential Revisions: -------------------------------------+------------------------------------- Comment (by goldfire): For reasons I'm not quite sure of (performance, probably), the following classes are always derived using GND when derived for newtypes: `Eq`, `Ord`, `Ix`, `Bounded`. This is true in a file with no extensions enabled. I don't know precisely why `Eq` didn't trigger this bug, but it wasn't worth exploring. -- Ticket URL: http://ghc.haskell.org/trac/ghc/ticket/10642#comment:6 GHC http://www.haskell.org/ghc/ The Glasgow Haskell Compiler