GitLab

Merge the eval-apply-branch on to the HEAD
------------------------------------------

This is a change to GHC's evaluation model in order to ultimately make
GHC more portable and to reduce complexity in some areas.

At some point we'll update the commentary to describe the new state of
the RTS.  Pending that, the highlights of this change are:

  - No more Su.  The Su register is gone, update frames are one
    word smaller.

  - Slow-entry points and arg checks are gone.  Unknown function calls
    are handled by automatically-generated RTS entry points (AutoApply.hc,
    generated by the program in utils/genapply).

  - The stack layout is stricter: there are no "pending arguments" on
    the stack any more, the stack is always strictly a sequence of
    stack frames.

    This means that there's no need for LOOKS_LIKE_GHC_INFO() or
    LOOKS_LIKE_STATIC_CLOSURE() any more, and GHC doesn't need to know
    how to find the boundary between the text and data segments (BIG WIN!).

  - A couple of nasty hacks in the mangler caused by the neet to
    identify closure ptrs vs. info tables have gone away.

  - Info tables are a bit more complicated.  See InfoTables.h for the
    details.

  - As a side effect, GHCi can now deal with polymorphic seq.  Some bugs
    in GHCi which affected primitives and unboxed tuples are now
    fixed.

  - Binary sizes are reduced by about 7% on x86.  Performance is roughly
    similar, some programs get faster while some get slower.  I've seen
    GHCi perform worse on some examples, but haven't investigated
    further yet (GHCi performance *should* be about the same or better
    in theory).

  - Internally the code generator is rather better organised.  I've moved
    info-table generation from the NCG into the main codeGen where it is
    shared with the C back-end; info tables are now emitted as arrays
    of words in both back-ends.  The NCG is one step closer to being able
    to support profiling.

This has all been fairly thoroughly tested, but no doubt I've messed
up the commit in some way.

Handle bindings to just a pattern variable in cvtd.

Update config.guess and config.sub from GNU; a bug was reported in the
previous versions.

Improved foreign import conversion.

wibbles to External Core

Behave decently if there are NoStubs in ForeignStubs

Change interface to mkIfaceOrig

Better comparision for Exact RdrNames

Original names can occur in binding positions in External Core

Give -> the correct kind!

Use real datatypes for TH Clause and Match

Check for qualified names in binding positions in the parser instead
of the rename.  In External Core it's OK to have qualified names in
these places.

Parse Word literals

Remove checkGHCI

Use layout inside declarations quasi-quotes [d| ... |]

Wibble

Report TH errors better in stage 1

Fix a race condition/possible deadlock in the threaded rts:

If a callback into haskell finished before waitThread_() was called,
the signal was lost  ans waitThread_() waited indefinitely.

Solution: Don't release the sched_mutex between calls to scheduleThread_
and waitThread_.

Please note that the scheduler API function waitThread is still possibly
affected by this race condition. It's used in rts_mainEvalIO (I think that's
safe) and in finishAllThreads (this looks dangerous, but finishAllThreads is
never used).

Correctly convert expressions from TH datastructures to the internel Hs*
datastructures containing right infix operators left-parenthesised.

Mac OS X: fix a small bug that caused trouble with object splitting

config.guess says "m68k-apple-netbsd1.6", and that's fine.

Stub objects are called foo_stub.o, not foo.stub_o.  In other words,
findLinkable (aka maybe_getFileLinkable in the 5.04 branch) has never
worked.

A new rejig script which takes arguments rather than hardwired locations.

Add SA_RESETHAND (aka SA_ONESHOT) support.
Requested by: John Meacham

> module Main where

> import System.Posix.Signals

> main = do
>   installHandler sigUSR1 (Catch (print "usr1")) Nothing
>   installHandler sigUSR2 (CatchOnce (print "usr2")) Nothing
>   _ <- getLine
>   return ()

- remove old code for GHC < 3.03 (we don't support building GHC with
  less than 4.08).

- remove ErrorHdrHook and PatError, we now catch all exceptions at
  the top level and report panics (this will fix some test
  discrepancies with GHCi).

Don't put a recursive exception handler around the flushing of
stdout/stderr after running a command.  If the user closes stdout or
stderr, we now fail rather than going into an infinite loop.

Let configure know about perl v5.8

Fix SPECIALISE documentation to not mention outdated syntax, and fix
the RULES syntax in one place

Add an extra <P>..</P> around the list of packages under "hierarchical
libraries", to fix ugly spacing in IE.  I have no idea if this is
valid HTML or not.

Use the right PackageIfaceTable in cmInfoThing

Remember to zapToType in tcSpliceExpr

Fix a bug and clean up some cruft in here:

 - In each function in the rts_getXXXX() family, there was a test that
   the object is actually of the desired type by examining its info
   table.  Some of these tests were disabled, but there was no comment
   explaining why.  I've just (re-)discovered the reason: the
   info table might be dynamically-loaded in the GHCi case.

   Not all the tests were disabled, which lead to bugs using the FFI
   in GHCi (in particular with functions that return Float or Double).

 - I've added consistent, but commented out, assertions to each of
   the rts_getXXXX() functions, and left a comment explaining why
   these reasonable-looking assertions are disabled.

MERGE TO STABLE

Add a FAQ item about long link times.

-------------------------------
      A day's work to improve error messages
	-------------------------------

1.  Indicate when the cause of the error is likely to be the monomorpism
    restriction, and identify the offending variables.  This involves
    mainly tcSimplifyTop and its error generation.

2.  Produce much better kind error messages.  No more
      ../alonzo/DiGraph.hs:40:
	  Couldn't match `* -> *' against `Type bx'
	      Expected kind: * -> *
	      Inferred kind: Type bx
	  When checking that `DiGraph n' is a type

It took a surprisingly long time to get the details right.

Report over-size tuples gracefully

Document a couple more bugs

Add a getting started example.  Someone with Docbook please check the SGML.

mblockIsHeap has been removed so update mingw32 branch - SIMON CHECK PLS!

Two files that shouldn't have been on the HEAD (yet)

Implement adjustor thunks for IA64.
N.B. malloc'd memory isn't executable, so I'm currently allocating them
on the (mmap'd) Haskell heap instead...