ghci: tweak option list indentation in ':show packages'

Summary:
Caught by './validate --slow' in 'ghci/scripts/ghci024'.

Commit 207875293fea07aa90efe215369629b657d1875a changed indentation a bit:

    --- ./ghci/scripts/ghci024.stdout       2014-07-31 12:05:34.000000000 +0300
    +++ ./ghci/scripts/ghci024.run.stdout   2014-08-07 17:19:23.000000000 +0300
    @@ -33,4 +33,4 @@
     active package flags: none
     ~~~~~~~~~~ Testing :show packages, including the ghc package
     active package flags:
    -  -package ghc
    +-package ghc

Patch restores indentation.

Signed-off-by: Sergei Trofimovich <slyfox@gentoo.org>

Test Plan: passed validate, tested manually

Reviewers: austin, ezyang

Reviewed By: ezyang

Subscribers: phaskell, simonmar, relrod, ezyang, carter

Differential Revision: https://phabricator.haskell.org/D126
testsuite: add signal_exit_code function to the driver

Summary:
New function signal_exit_code hides differences between target platforms
handling of fatal error signals and the applications' exit codes. E.g.
on Linux the application exit code which receives fatal error signal
is encoded as 128 + signal value. On the other hand on Solaris
the application exit code is signal value alone.

Test Plan: validated on Linux and tested on Solaris

Reviewers: austin, simonmar

Reviewed By: simonmar

Subscribers: phaskell, simonmar, relrod, ezyang, carter

Differential Revision: https://phabricator.haskell.org/D122
Update perf number for T5642

This  +4% increase (from -1% before) was caused by 1fc60ea. But that
commit did not cause any other regressions, so I’m not investigating
further.
Update Haddock to attoparsec-0.12.1. Adjust perf.

Please adjust the perf number on your platform if/when it fails. It
should improve slightly. Updates submodule.
Implement the final change to INCOHERENT from Trac #9242

The change here is to make INCOHERENT slightly more permissive:

  if the selected candidate is incoherent
  then ignore all unifying candidates

This allows us to move the {-# INCOHERENT #-} pragma from
  from   instance Typeable (f a)
  to     Typeable (n:Nat) and Typable (s:Symbol)
where it belongs, and where Trac #9242 said it should be.

I don't think this will affect anyone.

I've updated the user manual.
shouldInlinePrimOp: Fix Int overflow

Summary:
There were two overflow issues in shouldInlinePrimOp. The first one is
due to a negative CmmInt literal being created if the array size was
given as larger than 2^63-1 (on a 64-bit platform.) This meant that
large array sizes could compare as being smaller than
maxInlineAllocSize.

The second issue is that we casted the Integer to an Int in the
comparison, which again meant that large array sizes could compare as
being smaller than maxInlineAllocSize.

The attempt to allocate a large array inline then caused a segfault.

Fixes #9416.

Test Plan: Ran rts/overflow1

Reviewers: simonmar, austin

Subscribers: simonmar, relrod, ezyang, carter

Differential Revision: https://phabricator.haskell.org/D128

GHC Trac Issues: #9416
Add some Haddocks to SMRep