Re: [Discuss-gnuradio] SWIG 1.3.31 now required on the trunk

[Eric Blossom]

On Thu, Nov 30, 2006 at 06:22:30PM -0500, Lamar Owen wrote:
> On Thursday 30 November 2006 18:01, Eric Blossom wrote:
> > We've decided to require SWIG 1.3.31 to compile the trunk.
> 
> Really.  This makes support on anything older than bleeding edge very 
> difficult.

No, not very difficult.  You do have to download and build SWIG 1.3.31.

> > We try to avoid upping the mininum rev level of any our dependencies,
> > but this one's required for proper support of SWIG "directors".
> 
> What do 'directors' do that GNUradio has to have?  In other words, why the 
> need?  Just curious.  

They:

  (1) allow Python to subclass C++ base classes with virtual functions,
  (2) allow C++ code to transparently invoke Python code

This is used in gr_bin_statistics_f.{h,cc} and usrp_spectrum_sense.py
to allow C++ code to fire callbacks written in Python or C++.

See http://www.swig.org/Doc1.3/Python.html#directors for more info.

> > Sorry for any inconvenience this may bring.
> 
> Sorry for sounding less than thrilled at the thought of having to go back to 
> the bad old days of multiple SWIG versions (thought I was over that once I 
> got up to Fedora Core 5 from CentOS 4).  It could be more than just an 
> inconvenience to some (depending upon how old their distribution is), and 
> that's why I'm curious why it has to be 1.3.But again, I'm just curious, as I 
> didn't see much discussion on the list prior to this (or I'm just blind to 
> the messages, one).

The problems that David Reed and others were seeing are fixed by using
SWIG 1.3.31.  It is also required if anyone wants to use Python 2.5.


>From the SWIG README:

    What's New?
    ===========

    SWIG-1.3.31 summary:
    - Python modern classes regression fix

    SWIG-1.3.30 summary:
    - Python-2.5 support
    - New language module: R
    - Director support added for C#
    - Numerous director fixes and improvements
    - Improved mingw/msys support
    - Better constants support in Guile and chicken modules
    - Support for generating PHP5 class wrappers
    - Important Java premature garbage collection fix
    - Minor improvements/fixes in cffi, php, allegrocl, perl, chicken, lua, 
ruby,
      ocaml, python, java, c# and guile language modules
    - Many many other bug fixes



Eric