#14519: Exponential runtime performance regression in GHC 8.2 + Data.Text.Lazy + Text.RE.TDFA -------------------------------------+------------------------------------- Reporter: ntc2 | Owner: tdammers Type: bug | Status: new Priority: normal | Milestone: 8.4.1 Component: Compiler | Version: 8.2.2 Resolution: | Keywords: Operating System: Unknown/Multiple | Architecture: | Unknown/Multiple Type of failure: Runtime | Test Case: performance bug | https://github.com/ntc2/ghc-8.2.1 | -regex-lazy-text- | bug/tree/07b7bb32c6e90e8f2d2eada4b59943f37e632d53 Blocked By: | Blocking: Related Tickets: #13745, #14564 | Differential Rev(s): Wiki Page: | -------------------------------------+------------------------------------- Comment (by simonpj): Another line of approach.... Does the problem happen without `-O`? If not (and I bet it doesn't), then which modules must be compiled without `-O` to make the problem go away? And if compiling M without -O makes the problem go away, try with `-O` and `-fno-float-in` and other similar things to switch off various optimisations. -- Ticket URL: http://ghc.haskell.org/trac/ghc/ticket/14519#comment:26 GHC http://www.haskell.org/ghc/ The Glasgow Haskell Compiler