#11789: Flag suggestion does not always work -------------------------------------+------------------------------------- Reporter: nomeata | Owner: Type: feature request | Status: new Priority: normal | Milestone: Component: Driver | Version: 8.0.1 Resolution: | Keywords: newcomer Operating System: Unknown/Multiple | Architecture: | Unknown/Multiple Type of failure: None/Unknown | Test Case: Blocked By: | Blocking: Related Tickets: #11429 | Differential Rev(s): Wiki Page: | -------------------------------------+------------------------------------- Changes (by thomie): * version: 8.1 => 8.0.1 * related: => #11429 Comment: ghc-8.0.1 never suggests alternative spellings for misspelled //warning// flags. This should be fixed as well. With `-Wno-unrecognised-warning-flags` (#11429), unknown warning flags on the command line are now reported as warnings instead of errors, so they never reach the `unknownFlagsErr` function in `ghc/Main.hs`. The issue with `-fppr-cols=1000` vs `-dppr-cols=1000` is that the edit distance is too large. The flag passed to the fuzzy matcher should probably break at the `'='` character. From `fuzzyLookup` in `compiler/utils/Util.hs`: {{{ -- Work out an approriate match threshold: -- We report a candidate if its edit distance is <= the threshold, -- The threshhold is set to about a quarter of the # of characters the user entered -- Length Threshold -- 1 0 -- Don't suggest *any* candidates -- 2 1 -- for single-char identifiers -- 3 1 -- 4 1 -- 5 1 -- 6 2 }}} -- Ticket URL: http://ghc.haskell.org/trac/ghc/ticket/11789#comment:1 GHC http://www.haskell.org/ghc/ The Glasgow Haskell Compiler