Problems running "hg convert" with "subversion[-python]" 1.8.13-2

[Dr Rainer Woitok]

Greetings,

having installed  Cygwin's version  1.8.13-2  of both,  "subversion" and
"subversion-python", I get

$ hg convert -d hg -s svn http://gpsbabel.googlecode.com/svn/ gpsbabel
** unknown exception encountered, please report by visiting
** http://mercurial.selenic.com/wiki/BugTracker
** Python 2.7.10 (default, Jun  1 2015, 18:17:45) [GCC 4.9.2]
** Mercurial Distributed SCM (version 3.4.2+5-601da1db19f7)
** Extensions loaded: convert, histedit, strip, mq
Traceback (most recent call last):
  File "/home/Rainer/bin/hg", line 43, in <module>
    mercurial.dispatch.run()
  File "/home/Rainer/repo/mercurial/mercurial/dispatch.py", line 29, in run
    sys.exit((dispatch(request(sys.argv[1:])) or 0) & 255)
  File "/home/Rainer/repo/mercurial/mercurial/dispatch.py", line 91, in dispatch
    ret = _runcatch(req)
  File "/home/Rainer/repo/mercurial/mercurial/dispatch.py", line 160, in _runcatch
    return _dispatch(req)
  File "/home/Rainer/repo/mercurial/mercurial/dispatch.py", line 885, in _dispatch
    cmdpats, cmdoptions)
  File "/home/Rainer/repo/mercurial/mercurial/dispatch.py", line 646, in runcommand
    ret = _runcommand(ui, options, cmd, d)
  File "/home/Rainer/repo/mercurial/mercurial/dispatch.py", line 976, in _runcommand
    return checkargs()
  File "/home/Rainer/repo/mercurial/mercurial/dispatch.py", line 947, in checkargs
    return cmdfunc()
  File "/home/Rainer/repo/mercurial/mercurial/dispatch.py", line 882, in <lambda>
    d = lambda: util.checksignature(func)(ui, *args, **cmdoptions)
  File "/home/Rainer/repo/mercurial/mercurial/util.py", line 716, in check
    return func(*args, **kwargs)
  File "/home/Rainer/repo/mercurial/hgext/convert/__init__.py", line 338, in convert
    return convcmd.convert(ui, src, dest, revmapfile, **opts)
  File "/home/Rainer/repo/mercurial/mercurial/demandimport.py", line 106, in __getattribute__
    self._load()
  File "/home/Rainer/repo/mercurial/mercurial/demandimport.py", line 78, in _load
    mod = _hgextimport(_import, head, globals, locals, None, level)
  File "/home/Rainer/repo/mercurial/mercurial/demandimport.py", line 47, in _hgextimport
    return importfunc(name, globals, *args)
  File "/home/Rainer/repo/mercurial/hgext/convert/convcmd.py", line 13, in <module>
    from subversion import svn_source, svn_sink
  File "/home/Rainer/repo/mercurial/mercurial/demandimport.py", line 134, in _demandimport
    mod = _hgextimport(_origimport, name, globals, locals)
  File "/home/Rainer/repo/mercurial/mercurial/demandimport.py", line 47, in _hgextimport
    return importfunc(name, globals, *args)
  File "/home/Rainer/repo/mercurial/hgext/convert/subversion.py", line 25, in <module>
    from svn.core import SubversionException, Pool
  File "/home/Rainer/repo/mercurial/mercurial/demandimport.py", line 134, in _demandimport
    mod = _hgextimport(_origimport, name, globals, locals)
  File "/home/Rainer/repo/mercurial/mercurial/demandimport.py", line 47, in _hgextimport
    return importfunc(name, globals, *args)
  File "/usr/lib/python2.7/site-packages/svn/core.py", line 26, in <module>
    from libsvn.core import *
  File "/home/Rainer/repo/mercurial/mercurial/demandimport.py", line 115, in _demandimport
    return _hgextimport(_import, name, globals, locals, fromlist, level)
  File "/home/Rainer/repo/mercurial/mercurial/demandimport.py", line 47, in _hgextimport
    return importfunc(name, globals, *args)
  File "/usr/lib/python2.7/site-packages/libsvn/core.py", line 7285, in <module>
    svn_pool_create()
TypeError: svn_pool_create() takes exactly 2 arguments (0 given)

However, going back to version  1.8.13-1 of both, "subversion" and "sub-
version-python", I get the expected result:

$ hg convert -d hg -s svn http://gpsbabel.googlecode.com/svn/ gpsbabel
initializing destination gpsbabel repository
scanning source...
... and so on ...

Sincerely,
  Rainer

PS: I "Cc:"-ed the Mercurial people because -- even though I'm convinced
this is a Cygwin problem -- I think they should at least know.