Re: [GHC] #11760: runST with lazy blackholing breaks referential transparency

#11760: runST with lazy blackholing breaks referential transparency -------------------------------------+------------------------------------- Reporter: Yuras | Owner: dfeuer Type: bug | Status: patch Priority: highest | Milestone: 8.2.1 Component: Core Libraries | Version: 7.10.3 Resolution: | Keywords: Operating System: Unknown/Multiple | Architecture: Type of failure: Incorrect result | Unknown/Multiple at runtime | Test Case: Blocked By: | Blocking: Related Tickets: | Differential Rev(s): Phab:D3038 Wiki Page: | -------------------------------------+------------------------------------- Comment (by David Feuer ): In [changeset:"2f5cb3d44d05e581b75a47fec222577dfa7a533e/ghc" 2f5cb3d4/ghc]: {{{ #!CommitTicketReference repository="ghc" revision="2f5cb3d44d05e581b75a47fec222577dfa7a533e" Attempt to make lazy ST thread safe Use `noDuplicate#` to prevent lazy `ST` thunks from being evaluated in multiple GHC threads. Some lazy `ST` functions added laziness that did not seem to be useful (e.g., creating lazy pairs that will never be matched unless one of their components is demanded). Stripped that out. Reviewers: ekmett, simonpj, bgamari, simonmar, austin, hvr Subscribers: rwbarton, thomie Differential Revision: https://phabricator.haskell.org/D3038 GHC Trac Issues: #11760 }}} -- Ticket URL: http://ghc.haskell.org/trac/ghc/ticket/11760#comment:15 GHC http://www.haskell.org/ghc/ The Glasgow Haskell Compiler