Re: [Boost-users] [signal,bind] upgrade problem from 1.33 to 1.34

From: Doug Gregor (dgregor_at_[hidden])
Date: 2007-10-29 09:07:16

On Oct 14, 2007, at 7:29 AM, David Angelo wrote:
> I have a problem with upgrading from boost version 1.33 to 1.34.
> My code runs fine with 1.33, but when compiling and linking againt  
> 1.34 I get the following runtime error (backtrace):
>
> <backtrace>
> #0  0x81d4c9b2 in void boost::function1<void, float,  
> std::allocator<void> >::ass
> ign_to<boost::_bi::bind_t<void, boost::_mfi::mf1<void, fpCTPart,  
> float>, boost::
> _bi::list2<boost::_bi::value
> <fpCTPart*>, boost::arg<1> (*)()> > >(boost::_bi::bi
> nd_t<void, boost::_mfi::mf1<void, fpCTPart, float>,  
> boost::_bi::list2<boost::_bi
> ::value<fpCTPart*>, boost::arg<1> (*)()> >)::stored_vtable ()
>    from /home/david/eclipseM6/toolManagement/lib/libfpCTToolPack.so
>
> #1  0xb4438841 in boost::function0<void, std::allocator<void>  
> >::clear (
>     this=0xa1a03fc) at /usr/include/boost/function/ 
> function_template.hpp:388
> [snip]
> </backtrace>

How odd.  If you trap this, what does  the boost::function1 object  
contain? Is the vtable pointer NULL, for example?

A few more questions:
        - Which compiler/platform?
        - Is this multi-threaded code?
        - Is there any way for me to reproduce this?

> Are there any changes between these to versions in the bind/signal  
> library? (Are they not backward compatible?)

There were changes to Function (which Signals relies on), but they  
should be backward-compatible. This definitely looks like a bug in  
Function.

        - Doug