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Boost 1.44
=================================================================================
force_include.hpp needs to be moved to boost/serialization/force_include.hpp
This file fixes serialization via base ptr bugs, for Boost version < 1.44


Boost 1.45, Serialisation crashes in release mode.
==================================================================================

FROM IBM:
We have a Boost patch fix that fixes Serialization library runtime problems experienced at -O3

The symptom's root cause is in singleton pattern of Serialization library that uses static object
that is created but not referenced. 
A trick in the library code is used to make a reference to this object by passing 
it to a function with empty body to keep it around for static initialization. 
Our optimizer aggressively inlines away the function with empty body, eliminating 
this trick of a reference. This explains why turning off inlining also works. 
Ensuring that we don't inline away this function will keep the static object around.

This is a questionable Boost trick which we will advise either not use, or protect under macros. 
The fix is in your Boost header and no compiler changes are needed.

The changes are in two header files attached:
boost/serialization/force_include.hpp and
boost/serialization/singleton.hpp

(See attached file: singleton.hpp)(See attached file: force_include.hpp)
(See attached file: header_diff_item2.txt)


Boost 1.45
=====================================================================================
1/boost will will not build cleanly due to a compilation error in v3 filesystem
the work around is to comment out the v3 file system dependencies.
in $BOOST_ROOT/libs/filesystem/build/Jamfile.v2

>>>>>> OR

Change file path.hpp:
FROM:
  //------------------------------------------------------------------------------------//
  //                             class path::iterator                                   //
  //------------------------------------------------------------------------------------//
 
  class path::iterator
    : public boost::iterator_facade<
      iterator,
      path const,
      boost::bidirectional_traversal_tag >
  {
    ....
TO:
  //------------------------------------------------------------------------------------//
  //                             class path::iterator                                   //
  //------------------------------------------------------------------------------------//
 
  class path::iterator
    : public boost::iterator_facade<
      path::iterator,
      path const,
      boost::bidirectional_traversal_tag >
  {
    ....

ie. since iterator_facade uses CRTP, the iterator is being interperted as "boost::iterator"
    passing "path::iterator" as the template argument fixes the compile error on AIX.
    This should be safe for other platforms as well

    This has been registered as a bug. ticket #4912

2/ Problems running python examples, with boost filesystem linked,


Python: Effects all boost versions where we want to embed python interpreter in C++
=====================================================================================
The following exe's,on AIX, python 2.5 64 bit, acc v11.1,
raise *hundreds* of warning messages of the type:
     ld: 0711-224 WARNING: Duplicate symbol: _PyObject_New.
linking with flags -bloadmap:PARM, reveals:

 _Py_NoneStruct            Objects/object.c(/usr/local/python64/lib/python2.5/config/libpython2.5.a[object.o])
    ** Duplicate **        /usr/local/python64/lib/python2.5/config/python.exp{.}
.Py_FatalError            Python/pythonrun.c(/usr/local/python64/lib/python2.5/config/libpython2.5.a[pythonrun.o])
    ** Duplicate **        /usr/local/python64/lib/python2.5/config/python.exp{.}

It appears that the symbols are defined libpython2.5.a and in the exports file 'python.exp':
removing the export file: -Wl,-bI:/usr/local/python64/lib/python2.5/config/python.exp 
from the link line removes the warning messages

This can be done explicitly: $BOOST_ROOT/tools/build/v2/tools/python.jam
Go to line: 992 and comment out <linkflags>-Wl,-bI:$(libraries[1])/python.exp
 
    else if $(target-os) = aix
    {
        alias python_for_extensions
            :
            : $(target-requirements)
            :
            : $(usage-requirements) # <linkflags>-Wl,-bI:$(libraries[1])/python.exp
            ;
    }
   

This is not an absolute requirement, if you can live with warnings messages.
The notes in python.jam seems to expect them: file python.jam

    # the Python framework, even when building extensions. Note that framework
    # builds of Python always use shared libraries, so we do not need to worry
    # about duplicate Python symbols.
           