#13426: compile-time memory-usage regression for DynFlags between GHC 8.0 and GHC 8.2 -------------------------------------+------------------------------------- Reporter: hvr | Owner: rwbarton Type: bug | Status: new Priority: high | Milestone: 8.2.1 Component: Compiler | Version: 8.1 Resolution: | 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: | -------------------------------------+------------------------------------- Comment (by simonpj): Wow, I have no idea how you found that! Well done.
Alternatively, one can insert a seqType into reallyRebuildCase:
That would be ''much'' better. That kills the leak when we build a `Case`, whereas the former alternative waits until the ''subsequent'' run of the simplifier before squashing it. Please add a `Note` to explain the `seq` (point to this ticket too). Does it need to be a `seqType` or will `seq` do? I expect that `seq` would be enough, since the `OutType` returned by `contResultType` is (I think) a result of calling `simplType`.
It must share structure with some other part of the program, but I'm not sure what.
My guess: `exprType` often returns that type. Still I'm surprised that it leads to a ''cumulative'' space leak (i.e. every growing). Does it? -- Ticket URL: http://ghc.haskell.org/trac/ghc/ticket/13426#comment:16 GHC http://www.haskell.org/ghc/ The Glasgow Haskell Compiler