#14626: No need to enter a scrutinised value -------------------------------------+------------------------------------- Reporter: heisenbug | Owner: heisenbug Type: bug | Status: new Priority: normal | Milestone: Component: Compiler | Version: 8.2.2 Resolution: | Keywords: performance Operating System: Unknown/Multiple | Architecture: | Unknown/Multiple Type of failure: None/Unknown | Test Case: Blocked By: | Blocking: Related Tickets: #13861 | Differential Rev(s): Wiki Page: | -------------------------------------+------------------------------------- Comment (by heisenbug):
There is only one place in the code generator namely
`StgCmmCon.buildDynCon'`. You could perhaps add (runtime) assertions there to see if any strict fields had un-tagged pointers. After adding a runtime assertion here, I found one smoking gun. Banged `IORef`s (a.k.a `newtype`d `STRef`s) should be tagged, but end up untagged e.g. in `Handle__`. I am investigating why this happens. -- Ticket URL: http://ghc.haskell.org/trac/ghc/ticket/14626#comment:28 GHC http://www.haskell.org/ghc/ The Glasgow Haskell Compiler