#15646: ghci takes super long time to find the type of large fractional number -------------------------------------+------------------------------------- Reporter: Johannkokos | Owner: | JulianLeviston Type: bug | Status: new Priority: normal | Milestone: 8.6.1 Component: GHCi | Version: 8.4.3 Resolution: | Keywords: newcomer Operating System: Unknown/Multiple | Architecture: Type of failure: Compile-time | Unknown/Multiple performance bug | Test Case: Blocked By: | Blocking: Related Tickets: | Differential Rev(s): Wiki Page: | -------------------------------------+------------------------------------- Comment (by JulianLeviston): Seems to be picking `Double` as the type... I noticed that `Double` over `1e309` parses as `Infinity`... {{{#!shell ghc git:(master) ✗ time ./inplace/bin/ghc-stage2 blah2.hs -ddump-tc -dppr- debug [1 of 1] Compiling Blah2 ( blah2.hs, blah2.o ) TYPE SIGNATURES (main:Blah2.$trModule{v r1} [lidx] :: ghc-prim:GHC.Types.Module{tc 622}) :: ghc-prim:GHC.Types.Module{tc 622} (main:Blah2.largeValue{v rpX} [lid] :: ghc-prim:GHC.Types.Double{(w) tc 3k}) :: ghc-prim:GHC.Types.Double{(w) tc 3k} TYPE CONSTRUCTORS COERCION AXIOMS Dependent modules: [] Dependent packages: [base, ghc-prim, integer-gmp] blah2.hs:1:1: ==================== Typechecker ==================== {<no location info>} ((main:Blah2.$trModule{v r1} [lidx] :: ghc-prim:GHC.Types.Module{tc 622}) :: ghc-prim:GHC.Types.Module{tc 622}) = ghc-prim:GHC.Types.Module{d 625} {<no location info>} (ghc-prim:GHC.Types.TrNameS{d 62b} {<no location info>} "main"#) {<no location info>} (ghc-prim:GHC.Types.TrNameS{d 62b} {<no location info>} "Blah2"#) {blah2.hs:3:1-22} {blah2.hs:3:1-22} (largeValue{v aLS} [lid] :: ghc-prim:GHC.Types.Double{(w) tc 3k}) :: ghc-prim:GHC.Types.Double{(w) tc 3k} [LclId] main:Blah2.largeValue{v rpX} = {blah2.hs:3:14-22} 1e1000000 (base:GHC.Real.fromRational{v 02C} {<no location info>} 1e1000000) <> ./inplace/bin/ghc-stage2 blah2.hs -ddump-tc -dppr-debug 0.27s user 0.21s system 96% cpu 0.505 total }}} -- Ticket URL: http://ghc.haskell.org/trac/ghc/ticket/15646#comment:5 GHC http://www.haskell.org/ghc/ The Glasgow Haskell Compiler