#10571: GHC 7.10.1 segfaults when shiftL-ing Integers by negative amounts -------------------------------------+------------------------------------- Reporter: anders_ | Owner: Type: bug | Status: new Priority: high | Milestone: Component: Compiler | Version: 7.10.1 Resolution: | Keywords: Operating System: MacOS X | Architecture: x86_64 Type of failure: Runtime crash | (amd64) Blocked By: | Test Case: Related Tickets: | Blocking: | Differential Revisions: -------------------------------------+------------------------------------- Comment (by hvr): Right now, {{{#!hs instance Bits Integer where -- ... shift x i@(I# i#) | i >= 0 = shiftLInteger x i# | otherwise = shiftRInteger x (negateInt# i#) shiftL x (I# i#) = shiftLInteger x i# shiftR x (I# i#) = shiftRInteger x i# -- ... }}} The simplest fix would be to simply rename `shift{L,R}` to `unsafeShift{L,R}` -- Ticket URL: http://ghc.haskell.org/trac/ghc/ticket/10571#comment:2 GHC http://www.haskell.org/ghc/ The Glasgow Haskell Compiler