Hi Peter,
Is your program multithreaded? The problem occurs in the initialization of
the static variable 'stored_vtable' in function::assign_to. I don't see the
same code in 1.33, so this has indeed been introduced with 1.34. This
appears to be fixed in the current SVN trunk version, but the fix has not
been officially released yet as far as I can see.
You might try replacing function_template.hpp and function_base.hpp with
their latest versions from
http://svn.boost.org/trac/boost/browser/trunk/boost/function
and see if it helps.