Header conflict "using-declaration causes a multiple declaration of 'boost::iterators::use_default'"

[fsmoke@…]

I got "using-declaration causes a multiple declaration of 'boost::iterators::use_default'" error in my msvc. To reproduce bug you must create test.cpp with following text:

//test.cpp
#include <boost/type_erasure/iterator.hpp>
#include <boost/assign.hpp>

PS BUG appears only in boost 1.57.0, in older versions (for example 1.55.0) code compiles without errors.

[Steven Watanabe]

It looks like it was caused by this: ​http://github.com/boostorg/iterator/commit/dc96d371faf87a88c04057861136c9dfa68103d7

[anonymous]

Replying to steven_watanabe:

It looks like it was caused by this:

May be, anyway i'll be waiting fix of this issue

[Steven Watanabe]

A quick workaround is to delete the declarations of boost::use_default in boost/type_erasure/iterator.hpp and add a #include <boost/iterator/iterator_adaptor.hpp>. I'll need to think a bit more about what the right fix should be. It's too late for 1.58 anyway.

[anonymous]

Replying to steven_watanabe:

It's too late for 1.58 anyway.

I hope it will be fixed at least in 1.59

[fsmoke]

Replying to steven_watanabe:

It's too late for 1.58 anyway.

I hope it will be fixed at least in 1.59

[Domagoj Šarić]

Replying to steven_watanabe:

It's too late for 1.58 anyway.

Steven, this means that TypeErasure has been (and still is) broken on MSVC (and thus completely unusable for cross platform projects) for three consecutive Boost versions... Don't mean to sound harsh but that's quite off-putting (if not plain lame)...Are there some tests missing that should be added to catch these problems early?

[nat@…]

In Boost 1.59.0, (what I assume to be) another manifestation of the same bug is driven by this source:

#include <boost/iterator/iterator_adaptor.hpp>
#include <boost/type_erasure/any.hpp>

It's broken in either order, though the errors differ:

#include <boost/type_erasure/any.hpp>
#include <boost/iterator/iterator_adaptor.hpp>

My platform is Apple LLVM version 7.0.0 (clang-700.1.76) from Xcode 7.1.1.

[nat@…]

patch implementing Steven's suggested workaround

[nat@…]

Applying the attached 11181.patch allowed me to work around this problem.

[fsmoke@…]

when it be in release?

[Michel Morin]

Hey, did you try Boost 1.60 beta RC? I couldn't get errors using that version on clang trunk. You can get the beta RC ​here; see this ​ML post. (Note that Boost 1.60 beta has not yet been released.)

[Smithe353]

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