#11172: Turning on optimisations produces SEGFAULT or Impossible case alternative -------------------------------------+------------------------------------- Reporter: nh2 | Owner: bgamari Type: bug | Status: new Priority: highest | Milestone: 8.0.1 Component: Compiler | Version: 7.10.2 Resolution: | Keywords: Operating System: Unknown/Multiple | Architecture: | Unknown/Multiple Type of failure: Runtime crash | Test Case: Blocked By: | Blocking: Related Tickets: | Differential Rev(s): Wiki Page: | -------------------------------------+------------------------------------- Comment (by jscholl): I tried to break down the input data and arrieved at the following program triggering this bug. I derived it by taking the core before the bad transformation and simplified it. It still fails with an impossible case alternative when compiled with optimizations, but works without themIt is a lot smaller than the original code, so hopefully this helps in tracking down this bug. -- Ticket URL: http://ghc.haskell.org/trac/ghc/ticket/11172#comment:23 GHC http://www.haskell.org/ghc/ The Glasgow Haskell Compiler