#10555: RULE left-hand side too complicated to desugar -------------------------------------+------------------------------------- Reporter: yongqli | Owner: Type: bug | Status: new Priority: normal | Milestone: Component: Compiler | Version: 7.10.2-rc1 Resolution: | Keywords: Operating System: Unknown/Multiple | Architecture: Type of failure: None/Unknown | Unknown/Multiple Blocked By: | Test Case: yes Related Tickets: | Blocking: | Differential Revisions: -------------------------------------+------------------------------------- Description changed by yongqli: Old description:
GHC version 7.10.1.20150612 breaks the `fast-math` package, which compiled fine on GHC 7.10.1. To reproduce, run `cabal install fast-math`.
{{{
Numeric/FastMath/Approximation.hs:60:1: Warning: RULE left-hand side too complicated to desugar Optimised lhs: case /## y2 x of wild_00 { __DEFAULT -> (case /## y1 x of wild_X2 { __DEFAULT -> +## wild_X2 }) wild_00 } Orig lhs: case /## y2 x of wild_00 { __DEFAULT -> (case /## y1 x of wild_00 { __DEFAULT -> +## wild_00 }) wild_00 }
Numeric/FastMath/Approximation.hs:63:1: Warning: RULE left-hand side too complicated to desugar Optimised lhs: case /## y2 x of wild_00 { __DEFAULT -> (case /## y1 x of wild_X2 { __DEFAULT -> -## wild_X2 }) wild_00 } Orig lhs: case /## y2 x of wild_00 { __DEFAULT -> (case /## y1 x of wild_00 { __DEFAULT -> -## wild_00 }) wild_00 }
Numeric/FastMath/Approximation.hs:103:1: Warning: RULE left-hand side too complicated to desugar Optimised lhs: case divideFloat# y2 x of wild_00 { __DEFAULT -> (case divideFloat# y1 x of wild_X2 { __DEFAULT -> minusFloat# wild_X2 }) wild_00 } Orig lhs: case divideFloat# y2 x of wild_00 { __DEFAULT -> (case divideFloat# y1 x of wild_00 { __DEFAULT -> minusFloat# wild_00 }) wild_00 } ghc: panic! (the 'impossible' happened) (GHC version 7.10.1.20150612 for x86_64-unknown-linux): Simplifier ticks exhausted When trying RuleFired float commute left * 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: 4004
Please report this as a GHC bug: http://www.haskell.org/ghc/reportabug }}}
New description: GHC version 7.10.1.20150612 breaks the `fast-math` package, which compiled fine on GHC 7.10.1.20150519. To reproduce, run `cabal install fast-math`. {{{ Numeric/FastMath/Approximation.hs:60:1: Warning: RULE left-hand side too complicated to desugar Optimised lhs: case /## y2 x of wild_00 { __DEFAULT -> (case /## y1 x of wild_X2 { __DEFAULT -> +## wild_X2 }) wild_00 } Orig lhs: case /## y2 x of wild_00 { __DEFAULT -> (case /## y1 x of wild_00 { __DEFAULT -> +## wild_00 }) wild_00 } Numeric/FastMath/Approximation.hs:63:1: Warning: RULE left-hand side too complicated to desugar Optimised lhs: case /## y2 x of wild_00 { __DEFAULT -> (case /## y1 x of wild_X2 { __DEFAULT -> -## wild_X2 }) wild_00 } Orig lhs: case /## y2 x of wild_00 { __DEFAULT -> (case /## y1 x of wild_00 { __DEFAULT -> -## wild_00 }) wild_00 } Numeric/FastMath/Approximation.hs:103:1: Warning: RULE left-hand side too complicated to desugar Optimised lhs: case divideFloat# y2 x of wild_00 { __DEFAULT -> (case divideFloat# y1 x of wild_X2 { __DEFAULT -> minusFloat# wild_X2 }) wild_00 } Orig lhs: case divideFloat# y2 x of wild_00 { __DEFAULT -> (case divideFloat# y1 x of wild_00 { __DEFAULT -> minusFloat# wild_00 }) wild_00 } ghc: panic! (the 'impossible' happened) (GHC version 7.10.1.20150612 for x86_64-unknown-linux): Simplifier ticks exhausted When trying RuleFired float commute left * 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: 4004 Please report this as a GHC bug: http://www.haskell.org/ghc/reportabug }}} -- -- Ticket URL: http://ghc.haskell.org/trac/ghc/ticket/10555#comment:1 GHC http://www.haskell.org/ghc/ The Glasgow Haskell Compiler