#8731: long compilation time for module with large data type and partial record selectors -------------------------------------+------------------------------------- Reporter: carter | Owner: Type: bug | Status: new Priority: normal | Milestone: 7.10.1 Component: Compiler | Version: 7.8.1-rc1 Resolution: | Keywords: Operating System: | Architecture: Unknown/Multiple Unknown/Multiple | Difficulty: Unknown Type of failure: Compile- | Blocked By: time performance bug | Related Tickets: Test Case: | Blocking: | Differential Revisions: | -------------------------------------+------------------------------------- Comment (by thomie): Timing results for the example from comment:1. ||= GHC || -O1 || -O2 || ||= 7.4.2 || 4.9s || 16s || ||= 7.6.3 || 5.0s || 15s || ||= 7.8.3 || 4.4s || 12s || ||= 7.9.20141113 || 4.4s || 14s || Command: `time ghc -fforce-recomp -O<n> Constant.hs` Compilation takes only about 1 second, with either `-O1` or `-O2`, when I remove the `deriving (Eq, Ord, Read, Show)` clause from `data Constant`. The resulting object file also reduces in size from 1mb to 100kb. -- Ticket URL: http://ghc.haskell.org/trac/ghc/ticket/8731#comment:7 GHC http://www.haskell.org/ghc/ The Glasgow Haskell Compiler