#11710: Fusion of a simple listArray call is very fragile -------------------------------------+------------------------------------- Reporter: bgamari | Owner: Type: bug | Status: new Priority: normal | Milestone: Component: Compiler | Version: 7.10.3 Resolution: | Keywords: Operating System: Unknown/Multiple | Architecture: Type of failure: Runtime | Unknown/Multiple performance bug | Test Case: Blocked By: | Blocking: Related Tickets: | Differential Rev(s): Wiki Page: | -------------------------------------+------------------------------------- Comment (by bgamari): And here's a quick quiz for those playing along at home: How much unrolling would you expect to happen in this case? {{{#!hs arr :: Array Int Int arr = listArray (0,10) [ 1,1,1,-1,1,1,1,1,1,1 ] }}} **Answer**: The first four elements will be unrolled; the remaining will be constructed by recursive pattern matching against a CAF `[Int]` -- Ticket URL: http://ghc.haskell.org/trac/ghc/ticket/11710#comment:1 GHC http://www.haskell.org/ghc/ The Glasgow Haskell Compiler