Heap census now happens during GC, so that time is already accounted
for in GC_tot_cpu.

Now that the heap census runs in the middle of garbage collections,
the "CPU time" it was calculating included any CPU time used so far
in the current GC. This could cause CPU time to appear to go down,
which means hp2ps complained about "samples out of sequence".

I'm not sure if this is the nicest way to solve this (maybe resurrecting
mut_user_time_during_GC would be better?) but it gets things working again.

+RTS -hT and -threaded.

calling resurrectThreads() (fixes #5314).

This avoids a lot of problems, because resurrectThreads() may
overwrite some closures in the heap, leaving slop behind.  The bug in
instances, this fix avoids them all in one go.

Conflicts:

	rts/Schedule.c

assembly version as part of the fix for #5250, we inadvertently lost
the Windows magic for extending the stack.  Win32 requires that the
stack is extended a page at a time, otherwise you get a segfault.  The
C compiler knows how to do this, so we now call a C stub to ensure
there's enough stack space at each invocation of the scheduler.

to using MD5 hashes to identify TypeReps in the Typeable library.

(fixes various ffi test failures on x86.  This change was supposed to
be part of 9f61598c, but somehow it
got lost).

Previously we were completely ignoring these, due to the difficulties
of traversing the pinned blocks (the objects are not necessarily
end-to-end, we can't tell how large the gaps are).  Now just count the
whole block as a big ARR_WORDS, so at least we're accounting for the
memory and it has the right type.

as it maintains 16-byte alignment of the stack pointer (see #5250)

wrong platform by mistake.

The OS X ABI requires the C stack pointer to be 16-byte aligned at a
function call.  As far as I know this is not a requirement on other
x86 ABIs, but it seems that gcc is now generating SSE2 code that
assumes stack alignment (-mincoming-stack-boundary defaults to 4), so
we have to respect 16-byte alignment.

Based on a patch from David Terei.

Some parts are a little ugly (e.g. defining things that only ASSERTs
use only when DEBUG is defined), so we might want to tweak things a
little.

I've also turned off -Werror for didn't-inline warnings, as we now
get a few such warnings.

We were calling freeArgv with arguments of the wrong type.
But actually, we had our own copy of its loop anyway, so
now we just use that instead.

-feager-blackholing (#5226).  See comments for details.

A missing ';' that just happened to work fine on non-windows due
to differing definitions of the ACQUIRE_LOCK macro.

The process ID, parent process ID, rts name and version
The program arguments and environment.

We trace the creation and shutdown of capabilities. All the capabilities
in the process are assigned to one capabilitiy set of OS-process type.

This is a second version of the patch. Includes work by Spencer Janssen.

Rather than doing it differently for the eventlog and Dtrace cases.

This is mostly for the beneift of having sensible places to put tracing
code later. We want a code path that has somewhere to trace (in order):
 (1) starting up all capabilities;
 (2) N * starting up an individual capability;
 (3) N * shutting down an individual capability;
 (4) shutting down all capabilities.
This has to work in both threaded and non-threaded modes.

Locations (1) and (2) are provided by initCapabilities and
initCapability respectively. Previously, there was no loccation for (4)
and while shutdownCapability should be usable for (3) it was only called
in the !THREADED_RTS case.

Now, shutdownCapability is called unconditionally (and the body is
conditonal on THREADED_RTS) and there is a new shutdownCapabilities that
calls shutdownCapability in a loop.

setupRtsFlags(), rather than sharing the memory.  Previously if the
caller of hs_init() passed in dynamically-allocated memory and then
freed it, random crashes could happen later (#5177).

in the future.

This reverts commit 58532eb4.
Turns out it didn't work on Windows and it'll need some non-trivial changes
to make it work on Windows. We'll get it in later once that's sorted out.