Ditch static flags

This patch converts the 4 lasting static flags (read from the command
line and unsafely stored in immutable global variables) into dynamic
flags. Most use cases have been converted into reading them from a DynFlags.

In cases for which we don't have easy access to a DynFlags, we read from
'unsafeGlobalDynFlags' that is set at the beginning of each 'runGhc'.
It's not perfect (not thread-safe) but it is still better as we can
set/unset these 4 flags before each run when using GHC API.

Updates haddock submodule.

Rebased and finished by: bgamari

Test Plan: validate

Reviewers: goldfire, erikd, hvr, austin, simonmar, bgamari

Reviewed By: simonmar

Subscribers: thomie

Differential Revision: https://phabricator.haskell.org/D2839

GHC Trac Issues: #8440

1 files changed, 0 insertions, 0 deletions

diff --git a/utils/haddock b/utils/haddock
-Subproject 7f1987b35eb7bb15ca2fd93321440af519dd8cd
+Subproject dbbdabfd3842f70c78d4c64e10f75f47fe5c0f5