#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 simonpj): We have {{{ data STRef s a = STRef (MutVar# s a) newtype IORef a = IORef (STRef RealWorld a) data Handle__ = H !(IORef Char) }}} Indeed the pointer to the `MutVarf` is untagged; but heisenbug is claiming that the pointer to the `IORef`, stored in the `Handle__` is untagged. And that pointer should ''certainly'' be tagged. Smoking gun, I say, if I have correctly understood the claim. -- Ticket URL: http://ghc.haskell.org/trac/ghc/ticket/14626#comment:30 GHC http://www.haskell.org/ghc/ The Glasgow Haskell Compiler