#15562: `-XStrict -XNoStrict` is not neutral -------------------------------------+------------------------------------- Reporter: hvr | Owner: (none) Type: bug | Status: new Priority: normal | Milestone: 8.6.1 Component: Compiler | Version: 8.4.3 Keywords: | Operating System: Unknown/Multiple Architecture: | Type of failure: None/Unknown Unknown/Multiple | Test Case: | Blocked By: Blocking: | Related Tickets: Differential Rev(s): | Wiki Page: -------------------------------------+------------------------------------- I assumed we already had a ticket about this, but it appears we have not. I'm not saying this is a necessarily a bug in the implementation; but we should make sure this is properly documented in the user's guide, and ideally justify why it's done this way rather than the alternatives: As described in StrictPragma,
`Strict` implies `StrictData`
Currently however the inverse case does not hold, i.e. `NoStrict` does *not* imply `NoStrictData` This has the surprising property (assuming these were left-most flags on the CLI) that - `-XStrict -XNoStrict` == `-XStrictData` - `-XStrictData -XNoStrict` == `-XStrictData` However, if `-XNoStrict` was to naively imply `-XNoStrictData`, we'd have the properties - `-XStrict -XNoStrict` == *id* - `-XStrictData -XNoStrict` == *id* This might be a bit less confusing; another variant would be - `-XStrict -XNoStrict` == *id* - `-XStrictData -XNoStrict` == `-XStrictData` Btw, I'm not sure what the following means: - `-XStrict -XNoStrictData` == ? -- Ticket URL: http://ghc.haskell.org/trac/ghc/ticket/15562 GHC http://www.haskell.org/ghc/ The Glasgow Haskell Compiler