Add test case for #8144.

Based on:
  https://github.com/nh2/ghc-bug-time-dependent-interface-hashes

I verified that this test fails for GHC 7.6.3 and older, and passes
for GHC 7.8 and newer.

Signed-off-by: Austin Seipp <austin@well-typed.com>
rts: remove old-style field designator extension (#9396)

Authored-by: jrp

Signed-off-by: Austin Seipp <austin@well-typed.com>
The test runner now also works under the msys-native Python.

Msys binaries apply heuristics to escape paths in arguments intended for
non-msys binaries, which breaks timeout invocations, see #9626.

Signed-off-by: Austin Seipp <austin@well-typed.com>
Refactor: use System.FilePath.splitSearchPath

Summary:
To address #2521 ("Trailing colon on GHC_PACKAGE_PATH doesn't work with
ghc-pkg"), we were using a custom version of splitSearchPath (e4f46f5de). This
solution however caused issue #9698 ("GHC_PACKAGE_PATH should be more lenient
for empty paths").

This patch reverts back to System.FilePath.splitSearchPath (fixes #9698) and
adresses (#2521) by testing for a trailing search path separators explicitly
(instead of implicitly using empty search path elements).

Empty paths are now allowed (ignored on Windows, interpreted as current
directory on Posix systems), and trailing path separator still tack on the
user and system package databases.

Also update submodule filepath, which has a version of splitSearchPath which
handles quotes in the same way as our custom version did.

Test Plan:
$ GHC_PACKAGE_PATH=/::/home: ./ghc-pkg list
...
db stack: ["/",".","/home","<userdb>","<systemdb>"]
...

Reviewers: austin

Reviewed By: austin

Subscribers: thomie, carter, simonmar

Differential Revision: https://phabricator.haskell.org/D414

GHC Trac Issues: #2521, #9698
Update documentation for "Batch compiler mode"

Summary:
Since commit 7828bf3ea2ea34e7a3a8662f5f621ef706ffee5c
* --make is the default
* -c is a mode flag, except when used in combination with --make

Also:
* -C (generate C code) is only available in unregisterised mode.

Reviewers: austin

Reviewed By: austin

Subscribers: thomie, carter

Differential Revision: https://phabricator.haskell.org/D427
Implement new Foldable methods for HsPatSynDetails

Summary: Also explicitly define foldl1 and foldr1, which should generally work better with list-specific versions.

Reviewers: austin

Reviewed By: austin

Subscribers: rwbarton, thomie, carter

Differential Revision: https://phabricator.haskell.org/D430
Turn CoreWriter into a newtype; fix comment

Summary:
Turn CoreWriter into a newtype. A comment claimed something is forced
before returning, but it's actually not. Change comment to match
reality.

Reviewers: xich, simonpj, ezyang, austin

Reviewed By: ezyang, austin

Subscribers: thomie, carter

Differential Revision: https://phabricator.haskell.org/D453
Add remaining <unknown>s and comments to .mailmap

Summary:
All done, except for these 2 empty commits:

$ git log --author=unknown --use-mailmap --oneline
7e5c2b2 [project @ 2001-12-06 10:17:35 by mbs] Established under cvs.
6456598 [project @ 2000-12-01 10:33:41 by cryder] Initial revision

Reviewers: hvr, austin

Reviewed By: austin

Subscribers: thomie, carter

Differential Revision: https://phabricator.haskell.org/D477
Filter input to abiHash early

Summary:
This is already done near the only call site so why not. It is ugly to
see it at 'abiHash' itself.

Test Plan: validate

Reviewers: austin

Reviewed By: austin

Subscribers: thomie, carter

Differential Revision: https://phabricator.haskell.org/D491
template-haskell: Missing instances for Rational and ().

Test Plan: ./validate

Reviewers: austin

Reviewed By: austin

Subscribers: thomie, carter

Differential Revision: https://phabricator.haskell.org/D492
add missing instances for Loc and a few missing Eq instances

Summary: This adds a few missing instances that can be automatically derived

Reviewers: hvr, goldfire, austin

Reviewed By: goldfire, austin

Subscribers: thomie, carter

Differential Revision: https://phabricator.haskell.org/D495
Only test for bug #9439 when llvm is installed

Reviewers: bgamari, austin

Reviewed By: austin

Subscribers: thomie, carter

Differential Revision: https://phabricator.haskell.org/D500

GHC Trac Issues: #9807