#13027: The let/app invariant, evaluated-ness, and reallyUnsafePtrEquality# -------------------------------------+------------------------------------- Reporter: erikd | Owner: Type: bug | Status: new Priority: normal | Milestone: 8.2.1 Component: Compiler | Version: 8.1 Resolution: | Keywords: Operating System: Unknown/Multiple | Architecture: | Unknown/Multiple Type of failure: Building GHC | Test Case: failed | simplCore/should_compile/T13027 Blocked By: | Blocking: Related Tickets: #11444 | Differential Rev(s): Wiki Page: | -------------------------------------+------------------------------------- Comment (by Simon Peyton Jones <simonpj@…>): In [changeset:"5a9a1738023aeb742e537fb4a59c4aa8fecc1f8a/ghc" 5a9a173/ghc]: {{{ #!CommitTicketReference repository="ghc" revision="5a9a1738023aeb742e537fb4a59c4aa8fecc1f8a" Refine exprOkForSpeculation This patch implements two related changes, both inspired by the discussion on Trac #13027, comment:23: * exprOkForSpeculation (op# a1 .. an), where op# is a primop, now skips over arguments ai of lifted type. See the comments at Note [Primops with lifted arguments] in CoreUtils. There is no need to treat dataToTag# specially any more. * dataToTag# is now treated as a can-fail primop. See Note [dataToTag#] in primops.txt.pp I don't expect this to have a visible effect on anything, but it's much more solid than before. }}} -- Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/13027#comment:29> GHC <http://www.haskell.org/ghc/> The Glasgow Haskell Compiler