#15938: Hadrian's recompilation check is extremely slow -------------------------------------+------------------------------------- Reporter: bgamari | Owner: alpmestan Type: bug | Status: new Priority: high | Milestone: 8.8.1 Component: Build System | Version: 8.6.2 (Hadrian) | Resolution: | Keywords: Operating System: Unknown/Multiple | Architecture: | Unknown/Multiple Type of failure: None/Unknown | Test Case: Blocked By: | Blocking: Related Tickets: | Differential Rev(s): Wiki Page: | -------------------------------------+------------------------------------- Comment (by NeilMitchell): I actually managed to eliminate the ''O(n^2^)'' much more easily than expected. Now both builds take the same 0.31s. Having many rules is still going to be expensive for every file you match, but the cost is now not prohibitive. I'd still encourage the refactoring Alp is doing. I'll release a new Shake later today. -- Ticket URL: http://ghc.haskell.org/trac/ghc/ticket/15938#comment:34 GHC http://www.haskell.org/ghc/ The Glasgow Haskell Compiler