[GHC] #12790: GHC 8.0.1 uses copious amounts of RAM and time when trying to compile lambdabot-haskell-plugins

31 Oct 2016


      #12790: GHC 8.0.1 uses copious amounts of RAM and time when trying to compile
lambdabot-haskell-plugins
-------------------------------------+-------------------------------------
           Reporter:  clint          |             Owner:
               Type:  bug            |            Status:  new
           Priority:  normal         |         Milestone:
          Component:  Compiler       |           Version:  8.0.1
           Keywords:                 |  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:
-------------------------------------+-------------------------------------
 When building lambdabot-haskell-plugins,
 Lambdabot.Plugin.Haskell.Pl.Parser compiles without incident on the non-
 profiling run, but cripples the build machine on the profiling run.  An
 excerpt of -v3 output is below to show
 the number of terms skyrocketing.

     *** Common sub-expression [Lambdabot.Plugin.Haskell.Pl.Parser]:
     Result size of Common sub-expression
       = {terms: 39,049, types: 30,851, coercions: 990}
     !!! Common sub-expression [Lambdabot.Plugin.Haskell.Pl.Parser]:
 finished in 72.00 milliseconds, allocated 44.536 megabytes
     *** Float inwards [Lambdabot.Plugin.Haskell.Pl.Parser]:
     Result size of Float inwards
       = {terms: 39,049, types: 30,851, coercions: 990}
     !!! Float inwards [Lambdabot.Plugin.Haskell.Pl.Parser]: finished in
 68.00 milliseconds, allocated 60.337 megabytes
     *** Simplifier [Lambdabot.Plugin.Haskell.Pl.Parser]:
     Result size of Simplifier iteration=1
       = {terms: 977,045, types: 299,334, coercions: 1,058}
     Result size of Simplifier iteration=2
       = {terms: 926,036, types: 263,306, coercions: 932}
     Result size of Simplifier
       = {terms: 922,724, types: 262,202, coercions: 932}
     !!! Simplifier [Lambdabot.Plugin.Haskell.Pl.Parser]: finished in
 15480.00 milliseconds, allocated 9384.823 megabytes
     *** CoreTidy [Lambdabot.Plugin.Haskell.Pl.Parser]:
     Result size of Tidy Core
       = {terms: 922,623, types: 261,789, coercions: 865}
     !!! CoreTidy [Lambdabot.Plugin.Haskell.Pl.Parser]: finished in 2060.00
 milliseconds, allocated 613.585 megabytes
     writeBinIface: 95 Names
     writeBinIface: 259 dict entries
     *** CorePrep [Lambdabot.Plugin.Haskell.Pl.Parser]:
     Result size of CorePrep
       = {terms: 1,128,145, types: 347,063, coercions: 865}
     !!! CorePrep [Lambdabot.Plugin.Haskell.Pl.Parser]: finished in 3468.00
 milliseconds, allocated 1718.453 megabytes
     *** Stg2Stg:
     *** CodeGen [Lambdabot.Plugin.Haskell.Pl.Parser]:

--
Ticket URL: http://ghc.haskell.org/trac/ghc/ticket/12790
GHC http://www.haskell.org/ghc/
The Glasgow Haskell Compiler