[GHC] #15304: Huge increase of compile time and memory use from 8.0.2 to 8.2.2 or 8.4.2

GHC ghc-devs at haskell.org
Mon Jul 9 08:18:22 UTC 2018


#15304: Huge increase of compile time and memory use from 8.0.2 to 8.2.2 or 8.4.2
-------------------------------------+-------------------------------------
        Reporter:  NathanWaivio      |                Owner:  tdammers
            Type:  bug               |               Status:  new
        Priority:  high              |            Milestone:  8.6.1
       Component:  Compiler          |              Version:  8.4.2
      Resolution:                    |             Keywords:
Operating System:  Unknown/Multiple  |         Architecture:  x86_64
 Type of failure:  Compile-time      |  (amd64)
  performance bug                    |            Test Case:
      Blocked By:                    |             Blocking:
 Related Tickets:                    |  Differential Rev(s):
       Wiki Page:                    |
-------------------------------------+-------------------------------------

Comment (by tdammers):

 Steps to reproduce:

 1. Check out from git: {{{#!bash git clone
 https://github.com/waivio/cl3.git; cd cl3 }}}
 2. Install the `random` package (e.g. `cabal install random`)
 3. {{{#!bash cd cl3 }}}
 4. {{{#!bash ghc -c Algebra/Geometric/Cl3.hs -fforce-recomp -O2}}}

 Without `-O2`, things compile in under .1 seconds on my machine; adding
 `-O2` makes it take minutes.

-- 
Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/15304#comment:6>
GHC <http://www.haskell.org/ghc/>
The Glasgow Haskell Compiler


More information about the ghc-tickets mailing list