• thomie's avatar
    Dont call unsafeGlobalDynFlags if it is not set · 5166ee94
    thomie authored
    Parsing of static and mode flags happens before any session is started,
    i.e., before the first call to 'GHC.withGhc'. Therefore, to report
    errors for invalid usage of these two types of flags, we can not call
    any function that needs DynFlags, as there are no DynFlags available yet
    (unsafeGlobalDynFlags is not set either). So we always print "on the
    commandline" as the location, which is true except for Api users, which
    is probably ok.
    When reporting errors for invalid usage of dynamic flags we /can/ make
    use of DynFlags, and we do so explicitly in
    Before, we called unsafeGlobalDynFlags when an invalid (combination of)
    flag(s) was given on the commandline, resulting in panics (#9963). This
    regression was introduced in 1d6124de.
    Also rename showSDocSimple to showSDocUnsafe, to hopefully prevent this
    from happening again.
    Reviewed By: austin
    Differential Revision: https://phabricator.haskell.org/D730
    GHC Trac Issues: #9963
TcGenDeriv.hs 92.6 KB