#12967: GHC 8.0.1 Panic for current Aeson 1.0.2.1 -------------------------------------+------------------------------------- Reporter: bitemyapp | Owner: (none) Type: bug | Status: infoneeded Priority: normal | Milestone: Component: Compiler | Version: 8.0.1 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 mpickering): I think Ryan is right that the `INLINE` pragmas in `Data.Aeson.Encoding.Builder` are too aggressive. In this example, `utcTime` contains a call to `timeOfDay` which is a huge function marked with an `INLINE` pragma. This causes the unoptimised unfolding for `timeOfDay` to be inlined into the unfolding for `utcTime` which is then inlined 12 times in the example Ryan posted. So there is a lot of duplicated work because of how the inline pragmas cause unfoldings not to be optimised. -- Ticket URL: http://ghc.haskell.org/trac/ghc/ticket/12967#comment:4 GHC http://www.haskell.org/ghc/ The Glasgow Haskell Compiler