Re: [boost] [range] sub_range assignment issue

From: Sean Huang (huangsean_at_[hidden])
Date: 2007-09-29 22:32:06

> > The following simple problem produces an error when compiling with
> VC8+SP1
> > on Windows:
> >
> > #include <vector>
> > #include <boost/range/sub_range.hpp>
> >
> > int main(int argc, char* argv[])
> > {
> >     typedef std::vector< int > VectorType;
> >     VectorType v;
> >     boost::sub_range< VectorType > range;
> >     boost::sub_range< VectorType > range1;
> >     range = range1;
> > 	return 0;
> > }
> 
> Ditto copy-assignment operator.
> The workaround is to write copy-constructor/assignment "by hand".
> 
> In fact, this can't explain the exact behavior of msvc.
> My sub_range seems to work well, though.

Shunsuke,

Thanks for the analysis. I looked into this a bit more and found that the
workaround added for VC7.1 is giving VC8  problems (by the way, it only
happened in debug build, release build was fine).

I removed the operator= that accepts sub_range r passed by value and
everything started working.
Specifically, I commented out the following code in sub_range.hpp:

        sub_range& operator=( sub_range r )
        {
            //
            // argument passed by value to avoid 
            // const_iterator to iterator conversion
            //
            base::operator=( r );
            return *this;            
        }

Regards,

Sean