Can't compile boost/any_iterator.hpp in boost 1.57 - c++

Question

After (attempting to) upgrade a VS2012 project to use boost 1.57, I can no longer compile--lots and lots of error messages coming out of boost/any_iterator.hpp (see below). As a test, I created a new project that contained nothing but an empty main function and #include "boost/any_iterator.hpp" and got the same set of errors. Here is the code it's complaining about:
// snippet from boost/any_iterator.hpp
template<
class Value
, class Traversal
, class Reference
, class Difference
, class Buffer
>
class postfix_increment_proxy<
range_detail::any_iterator< // line 131
Value
, Traversal
, Reference
, Difference
, Buffer
>
>
{
// ...
};
There is another class in the same file that follows the same pattern and generates identical errors. range_detail::any_iterator is forward-declared a little higher up in the file:
namespace range_detail
{
// ...
template<
class Value
, class Traversal
, class Reference
, class Difference
, class Buffer = any_iterator_default_buffer
>
class any_iterator;
// ...
}
For what it's worth, here's the set of errors I get from VS2012:
Error 1 error C2143: syntax error : missing ';' before '<' [path]\boost\range\detail\any_iterator.hpp 131
Error 2 error C2059: syntax error : '<' [path]\boost\range\detail\any_iterator.hpp 131
Error 3 error C2065: 'Value' : undeclared identifier [path]\boost\range\detail\any_iterator.hpp 134
Error 4 error C2065: 'Traversal' : undeclared identifier [path]\boost\range\detail\any_iterator.hpp 135
Error 5 error C2065: 'Reference' : undeclared identifier [path]\boost\range\detail\any_iterator.hpp 136
Error 6 error C2065: 'Difference' : undeclared identifier [path]\boost\range\detail\any_iterator.hpp 137
Error 7 error C2065: 'Buffer' : undeclared identifier [path]\boost\range\detail\any_iterator.hpp 138
Error 8 error C2923: 'boost::range_detail::any_iterator' : 'Value' is not a valid template type argument for parameter 'Value' [path]\boost\range\detail\any_iterator.hpp 138
Error 9 error C2923: 'boost::range_detail::any_iterator' : 'Traversal' is not a valid template type argument for parameter 'Traversal' [path]\boost\range\detail\any_iterator.hpp 138
Error 10 error C2923: 'boost::range_detail::any_iterator' : 'Reference' is not a valid template type argument for parameter 'Reference' [path]\boost\range\detail\any_iterator.hpp 138
Error 11 error C2923: 'boost::range_detail::any_iterator' : 'Difference' is not a valid template type argument for parameter 'Difference' [path]\boost\range\detail\any_iterator.hpp 138
Error 12 error C2923: 'boost::range_detail::any_iterator' : 'Buffer' is not a valid template type argument for parameter 'Buffer' [path]\boost\range\detail\any_iterator.hpp 138
Error 13 error C2143: syntax error : missing ';' before '{' [path]\boost\range\detail\any_iterator.hpp 140
Error 14 error C2447: '{' : missing function header (old-style formal list?) [path]\boost\range\detail\any_iterator.hpp 140
Is anyone aware of a workaround?

Answer 1

This appears to be a bug in the boost codebase. postfix_increment_proxy and writable_postfix_increment_proxy are both in the boost::iterators::detail namespace (iterator_facade.hpp). However, both names are used unqualified in any_iterator.hpp. Adding boost::iterators::detail:: in front of both names allows the code to compile.
For anyone who's uncomfortable with the idea of editing boost code, including iterator_facade.hpp followed by using namespace boost::iterators::detail followed by an include for any_iterator.hpp will also solve the problem at the cost of namespace pollution. VS2012 doesn't support them so it doesn't do me any good, but you could presumably use a C++11 using too.
Ticket submitted:
https://svn.boost.org/trac/boost/ticket/10754