#15569: Constant folding optimises 1 into 3 -------------------------------------+------------------------------------- Reporter: snowleopard | Owner: (none) Type: bug | Status: new Priority: highest | Milestone: 8.6.1 Component: Compiler | Version: 8.6.1-beta1 Resolution: | Keywords: Operating System: Unknown/Multiple | Architecture: | Unknown/Multiple Type of failure: None/Unknown | Test Case: Blocked By: | Blocking: Related Tickets: #9136 | Differential Rev(s): Phab:D5109 Wiki Page: | -------------------------------------+------------------------------------- Comment (by sgraf): For the record, here's ~~a paper~~ [https://arxiv.org/pdf/1809.02161.pdf a report] about how these kind of optimisations should be specified in a declarative language (like snowleopard's attempt above). Ultimately, these declarations could be synthesised by an SMT solver out of a language semantics (a.k.a. algebraic structure, in our case). -- Ticket URL: http://ghc.haskell.org/trac/ghc/ticket/15569#comment:16 GHC http://www.haskell.org/ghc/ The Glasgow Haskell Compiler