[Lightning] lightning 1.2b released

[Paolo Bonzini]

The development snapshot release 1.2b of GNU lightning is now available 
from ftp://alpha.gnu.org/gnu/lightning/lightning-1.2b.tar.gz.

This version is to be considered feature complete.  Changes from 1.2b to 
1.3 will only include bug fixes.

New features are:

* Initial support for x86-64 back-end, contributed by Gwenole Beauchesne 
(run-time assembler) and Matthew Flatt (porting).  The x86-64 back-end 
also supports SSE floating-point math.

* lightning is more strict on casts from integer to pointer.   Be sure 
to use the _p variants when your immediates are of pointer type.  This 
was done to ease 64-bit cleanliness tests.

* Many bug fixes.

* JIT_FPRET is used as JIT_RET to move return values.  jit_retval_[fd] 
is used to retrieve return values.

* jit_pushr/jit_popr are deprecated, you need to #define 
JIT_NEED_PUSH_POP prior to including lightning.h if you want to use them.

* Support for stack-allocated variables.  Because of this, backends 
defining JIT_FP should now rename it to JIT_AP.  JIT_FP is now a 
user-visible register used in ldxi/ldxr to access stack-allocated 
variables.  This change was contributed by Ludovic Courtes.

* Support for Mac OS X running on Intel processors.

Bug reports are welcome.

Paolo