#11163: New exhaustiveness checker breaks T5642 -------------------------------------+------------------------------------- Reporter: bgamari | Owner: Type: bug | Status: new Priority: high | Milestone: 8.0.1 Component: Compiler | Version: 7.10.2 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: -------------------------------------+------------------------------------- The new exhaustiveness checker drastically increases compile time of the `T5642` testcase. From the profile it appears that a great deal of time is being spent evaluating `Check.mkPmId.occname`, {{{ COST CENTRE MODULE %time %alloc mkPmId.occname Check 73.7 16.9 mkOneConFull Check 3.4 10.2 deSugar HscMain 2.8 14.8 mkOneConFull.arguments Check 2.5 5.5 pmTraverse Check 1.6 0.8 mkOneConFull.subst1 Check 1.5 5.9 wrapK.go Check 1.5 5.9 cMatcher Check 1.2 2.7 canEvVar TcCanonical 1.0 3.4 }}} -- Ticket URL: http://ghc.haskell.org/trac/ghc/ticket/11163 GHC http://www.haskell.org/ghc/ The Glasgow Haskell Compiler