With GHC MR !8478, GHC is able to spot a redundant pattern match
when RLIM_SAVED_CUR == RLIM_SAVED_MAX, which it wasn't able to
detect before. So we use considerAccessible to avoid a pattern match
check. This unfortunately means we must change the SafeHaskell status
of that module to TrustWorth, as considerAccessible is from GHC.Exts,
which isn't safe.

Alternatives:

  - we can't perform the equality test RLIM_SAVED_CUR == RLIM_SAVED_MAX
    using CPP macros, because one of the values might expand out to
    have casts;
  - turning off pattern match warnings impacts warnings across the whole
    module, instead of the single affected function,
  - adding a dummy equation such as "id True" to the first pattern match
    would work, but seems more ad-hoc.