#9583: Simplifier ticks exhausted while compiling Cabal HEAD -------------------------------------+------------------------------------- Reporter: ezyang | Owner: Type: bug | Status: new Priority: highest | Milestone: Component: Compiler | Version: 7.9 Keywords: | Operating System: Architecture: Unknown/Multiple | Unknown/Multiple Difficulty: Unknown | Type of failure: Compile- Blocked By: | time crash Related Tickets: | Test Case: | Blocking: | Differential Revisions: -------------------------------------+------------------------------------- Steps to reproduce: 1. Clone Cabal HEAD 2. `cabal configure --with-ghc=/path/to/ghc-head` 3. `dist/setup/setup build` Actual results: {{{ [ 8 of 78] Compiling Distribution.Text ( Distribution/Text.hs, dist/build/Distribution/Text.o ) [ 9 of 78] Compiling Distribution.Version ( Distribution/Version.hs, dist/build/Distribution/Version.o ) ghc-stage2: panic! (the 'impossible' happened) (GHC version 7.9.20140911 for x86_64-unknown-linux): Simplifier ticks exhausted When trying UnfoldingDone GHC.Word.$fNumWord8_$c+ To increase the limit, use -fsimpl-tick-factor=N (default 100) If you need to do this, let GHC HQ know, and what factor you needed To see detailed counts use -ddump-simpl-stats Total ticks: 813720 Please report this as a GHC bug: http://www.haskell.org/ghc/reportabug }}} I know that it still fails with tick factor 4096; I haven't found a tick amount which makes it succeed. -- Ticket URL: http://ghc.haskell.org/trac/ghc/ticket/9583 GHC http://www.haskell.org/ghc/ The Glasgow Haskell Compiler