#4012: Compilation results are not deterministic -------------------------------------+------------------------------------- Reporter: kili | Owner: niteria Type: bug | Status: new Priority: high | Milestone: 8.2.1 Component: Compiler | Version: 6.12.2 Resolution: | Keywords: Operating System: Unknown/Multiple | Architecture: | Unknown/Multiple Type of failure: Other | Test Case: Blocked By: 11362 | Blocking: 12262 Related Tickets: #10424 | Differential Rev(s): Phab:D910, | Phab:D1073, Phab:D1133, Phab:D1192, | Phab:D1268, Phab:D1360, Phab:D1373, Wiki Page: | Phab:D1396, Phab:D1457, Phab:D1468, DeterministicBuilds | Phab:D1487, Phab:D1504, Phab:D1508 -------------------------------------+------------------------------------- Comment (by Bartosz Nitka ): In [changeset:"fb6e2c7fe213004c7398a13e3cc38d4428b66b12/ghc" fb6e2c7f/ghc]: {{{ #!CommitTicketReference repository="ghc" revision="fb6e2c7fe213004c7398a13e3cc38d4428b66b12" Delete Ord Unique Ord Unique can be a source of invisible, accidental nondeterminism as explained in Note [No Ord for Unique]. This removes it, leaving a note with rationale. It's unfortunate that I had to write Ord instances for codegen data structures by hand, but I believe that it's a right trade-off here. Test Plan: ./validate Reviewers: simonmar, austin, bgamari Reviewed By: simonmar Subscribers: thomie Differential Revision: https://phabricator.haskell.org/D2370 GHC Trac Issues: #4012 }}} -- Ticket URL: http://ghc.haskell.org/trac/ghc/ticket/4012#comment:219 GHC http://www.haskell.org/ghc/ The Glasgow Haskell Compiler