#15703: Significant compilation time blowup when refactoring singletons-heavy code -------------------------------------+------------------------------------- Reporter: RyanGlScott | Owner: (none) Type: bug | Status: new Priority: normal | Milestone: 8.8.1 Component: Compiler | Version: 8.6.1 Resolution: | Keywords: Operating System: Unknown/Multiple | Architecture: Type of failure: Compile-time | Unknown/Multiple performance bug | Test Case: Blocked By: | Blocking: Related Tickets: #15725 | Differential Rev(s): Wiki Page: | -------------------------------------+------------------------------------- Comment (by RyanGlScott): I tried compiling this program using the experimental Phab:D4766 (`Zap coercions when not building with -dcore-lint`) branch: {{{ $ time ~/Software/ghc3/inplace/bin/ghc-stage2 -O0 -fforce-recomp Lib.hs [1 of 2] Compiling Lib2 ( Lib2.hs, Lib2.o ) [2 of 2] Compiling Lib ( Lib.hs, Lib.o ) real 0m0.497s user 0m0.460s sys 0m0.028s $ time ~/Software/ghc3/inplace/bin/ghc-stage2 -O1 -fforce-recomp Lib.hs [1 of 2] Compiling Lib2 ( Lib2.hs, Lib2.o ) [2 of 2] Compiling Lib ( Lib.hs, Lib.o ) real 0m17.164s user 0m16.980s sys 0m0.200s }}} This looks promising! Perhaps this really is a duplicate of #8095 in disguise? -- Ticket URL: http://ghc.haskell.org/trac/ghc/ticket/15703#comment:8 GHC http://www.haskell.org/ghc/ The Glasgow Haskell Compiler