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Instead of asking for the last 100 patches, we just get the first 500
lines of output from darcs changes (ugh, better ideas welcome).

The code for -ddump-minimal-imports was erroneously using loadSrcInterface,
which looks only for *exposed* modules.  It should instead use loadSysInterface
which looks for all interfaces.

The fix is straightforward.  MERGE to 6.6 branch.

I added a slightly more helpful remark in the profiling
section of the manual about how to use ticky-ticky.

The following changes restore ticky-ticky profiling to functionality
from its formerly bit-rotted state. Sort of. (It got bit-rotted as part
of the switch to the C-- back-end.)

The way that ticky-ticky is supposed to work is documented in Section 5.7
of the GHC manual (though the manual doesn't mention that it hasn't worked
since sometime around 6.0, alas). Changes from this are as follows (which
I'll document on the wiki):

* In the past, you had to build all of the libraries with way=t in order to
use ticky-ticky, because it entailed a different closure layout. No longer.
You still need to do make way=t in rts/ in order to build the ticky RTS,
but you should now be able to mix ticky and non-ticky modules.

* Some of the counters that worked in the past aren't implemented yet.
I was originally just trying to get entry counts to work, so those should
be correct. The list of counters was never documented in the first place,
so I hope it's not too much of a disaster that some don't appear anymore.
Someday, someone (perhaps me) should document all the counters and what 
they do. For now, all of the counters are either accurate (or at least as
accurate as they always were), zero, or missing from the ticky profiling
report altogether.

This hasn't been particularly well-tested, but these changes shouldn't
affect anything except when compiling with -fticky-ticky (famous last
words...)

Implementation details:

I got rid of StgTicky.h, which in the past had the macros and declarations 
for all of the ticky counters. Now, those macros are defined in Cmm.h.
StgTicky.h was still there for inclusion in C code. Now, any remaining C
code simply cannot call the ticky macros -- or rather, they do call those
macros, but from the perspective of C code, they're defined as no-ops. 
(This shouldn't be too big a problem.)

I added a new file TickyCounter.h that has all the declarations for ticky
counters, as well as dummy macros for use in C code. Someday, these 
declarations should really be automatically generated, since they need
to be kept consistent with the macros defined in Cmm.h.

Other changes include getting rid of the header that was getting added to
closures before, and getting rid of various code having to do with eager
blackholing and permanent indirections (the changes under compiler/ 
and rts/Updates.*).

For non-release builds, we want to append a date to the version number
(e.g. 6.7.20070206).  Previously this was done by the nightly build
script, this new method figures out the snapshot version by querying
the darcs repository and finding the date of the most recent patch
(actually it finds the most recent of the last 100 patches, but that
should be good enough).  This is done by the configure script.

To handle source distributions, we create a file VERSION in the
top-level directory that contains the version number, and ship this in
the source distribution.  The configure script picks up the version
from this file if it doesn't see a _darcs directory.

This egregious omission led to Trac #1128.

This patch improves prepareRhs, so that it deals better with casts.

We want to deal well cases like this
	v = (f e1 `cast` co) e2
Here we want to make e1,e2 trivial and get
	x1 = e1; x2 = e2; v = (f x1 `cast` co) v2

This really happens in parser libraries, which wrap functions in newtypes.

See Note [Casts and lambdas] in SimplUtils.  I found this transformation
when staring at some cast-heavy code generated by
Language.Haskell.Lexer.hs in the haskell-src library.

The basic transformation is this:
	(\x. e `cast` g1)  -->  (\x.e) `cast` (tx -> g1)
where x:tx.

This patch clears up a long-standing wart.   For some time it's been the
case that 
	the RHS of a non-recursive let can be unlifed iff 
	the RHS is ok-for-speculation

This patch extends the invariant to the argument of an App, and 
establishes it by the smart constructors mkDsApp, mkDsApps in the desugarer.

Once established, it should be maintained by the optimiser.

This tides up some awkward cases, notably in exprIsHNF, and I think it
fixes a outright strictness bug in Simplify.prepareRhs.

At the moment GHC really does very little simplification of coercions.
This patch improves matters, but it's still not great, especially when
you have chains linked together with 'trans'. 

I'm also concerned that I have not yet implemented the 'leftc' and 'rightc'
coercions we added to the paper. 

But at least things are better than they were.  In particular
	g `trans` sym g
now cancels to give the identity.

Fixes bug exposed by compiling base w/ -fasm on Windows

Moving functionality that was previously in the nightly build scripts
into the top-level Makefile, so it's easier to use from BuildBot.

In the generated code for case-of-variable, test the tag of the
scrutinee closure and only enter if it is unevaluated.  Also turn
*off* vectored returns.

This version does all its work in a subdirectory (no more destructive
'make distclean' in the current build tree), and results in the exact
-src.tar.bz2 distributions that we will put up for download.

This is only turned on with -O, and probably won't make much
difference at the moment, but it will be important for semi-tagging.

In the generated code for case-of-variable, test the tag of the
scrutinee closure and only enter if it is unevaluated.  Also turn
*off* vectored returns.

Only affects -fasm: gcc makes its own decisions about jump tables

Comparison of literal with narrowed/widened operand: perform
the comparison at a different width, as long as the literal is
within range.  We only do this on x86/x86_64 at the moment, where
we have comparisons at different sizes available.