Original patch by Orphi <MathematicalOrchid@hotmail.com>
Plus a few miscellaneous updates from me.

Signed-off-by: Edward Z. Yang <ezyang@mit.edu>

* Do-notation in arrows is marked with HsStmtContext = ArrowExpr
* tcMDoStmt (which was only used for arrows) is moved
  to TcArrows, and renamed tcArrDoStmt
* Improved documentation in the user manual
* Lots of other minor changes

This is the work of Nils Schweinsberg <mail@n-sch.de>

It adds the language extension -XMonadComprehensions, which
generalises list comprehension syntax [ e | x <- xs] to work over
arbitrary monads.

Previously the code generator generated small code fragments labelled
with __stginit_M for each module M, and these performed whatever
initialisation was necessary for that module and recursively invoked
the initialisation functions for imported modules.  This appraoch had
drawbacks:

 - FFI users had to call hs_add_root() to ensure the correct
   initialisation routines were called.  This is a non-standard,
   and ugly, API.

 - unless we were using -split-objs, the __stginit dependencies would
   entail linking the whole transitive closure of modules imported,
   whether they were actually used or not.  In an extreme case (#4387,
   #4417), a module from GHC might be imported for use in Template
   Haskell or an annotation, and that would force the whole of GHC to
   be needlessly linked into the final executable.

So now instead we do our initialisation with C functions marked with
__attribute__((constructor)), which are automatically invoked at
program startup time (or DSO load-time).  The C initialisers are
emitted into the stub.c file.  This means that every time we compile
with -prof or -hpc, we now get a stub file, but thanks to #3687 that
is now invisible to the user.

There are some refactorings in the RTS (particularly for HPC) to
handle the fact that initialisers now get run earlier than they did
before.

The __stginit symbols are still generated, and the hs_add_root()
function still exists (but does nothing), for backwards compatibility.

in a LANGUAGE pragma, but it is parsed by parseDynamicFlags, and it
can be set per-session in the GHC API.  We don't have a name for this
type of flag, but from the user's point of view "static" is probably
less confusing.

This just disables the coercion optimiser, mainly for measurements in the paper

This dumps a (one-line) listing of the size of the Core program,
just after tidying

Patch from Brian Bloniarz

It might be nicer to actually go the other way, and make everything
use <section> instead, but this fixes the incorrect numbering for
now, and we can look into whether <section> has any disadvantages
later.

Also change the behaviour slightly, to warn only for
*unqualified* imports.  See Trac #4977.

This patch adds the script command in GHCi

A file is read and executed as a series of GHCi commands.

Execution terminates on the first error.  The filename and
line number are included in the error.

- Added a pragma {-# VECTORISE var = exp #-} that prevents
  the vectoriser from vectorising the definition of 'var'.
  Instead it uses the binding '$v_var = exp' to vectorise
  'var'.  The vectoriser checks that the Core type of 'exp'
  matches the vectorised Core type of 'var'.  (It would be
  quite complicated to perform that check in the type checker
  as the vectorisation of a type needs the state of the VM
  monad.)
- Added parts of a related VECTORISE SCALAR pragma
- Documented -ddump-vect
- Added -ddump-vt-trace
- Some clean up

It is still (silently) accepted for backwards compatibility.

The changes are:

* New flag -fwarn-incomplete-uni-patterns, which checks for
  incomplete patterns in (a) lambdas, (b) pattern bindings

* New flag is not implied by -W or -Wall (too noisy; and many
  libraries use incomplete pattern bindings)

* Actually do the incomplete-pattern check for pattern bindings
  (previously simply omitted)

* Documentation for new flag

We no longer use dummy-ghc; instead we don't configure most packages
until the stage1 compiler is available.
  
We also now use Cabal for building the ghc-bin package.

There are a couple more sanity checks too.

cygwin's /bin/install doesn't set file modes correctly if the
destination path is a C: style path:

$ /bin/install -c -m 644 foo /cygdrive/c/cygwin/home/ian/foo2
$ /bin/install -c -m 644 foo c:/cygwin/home/ian/foo3
$ ls -l foo*
-rw-r--r-- 1 ian None 0 2011-01-06 18:28 foo
-rw-r--r-- 1 ian None 0 2011-01-06 18:29 foo2
-rwxrwxrwx 1 ian None 0 2011-01-06 18:29 foo3

This causes problems for bindisttest/checkBinaries.sh which then
thinks that e.g. the userguide HTML files are binaries.

We therefore use a /cygdrive path if we are on cygwin

This patch adds support for multiline commands in GHCi.

The first line of input is lexed.  If there is an active
layout context once the lexer reaches the end of file, the
user is prompted for more input.

Multiline input is exited by an empty line and can be escaped 
with a user interrupt.

Multiline mode is toggled with `:set +m`

It doesn't do anything useful yet, but it works with the new build system