[Boost-bugs] [Boost C++ Libraries] #9508: 1.54 regression: boost/thread/once.hpp includes boost/placeholders.hpp

Subject: [Boost-bugs] [Boost C++ Libraries] #9508: 1.54 regression: boost/thread/once.hpp includes boost/placeholders.hpp
From: Boost C++ Libraries (noreply_at_[hidden])
Date: 2013-12-19 02:22:06

#9508: 1.54 regression: boost/thread/once.hpp includes boost/placeholders.hpp
------------------------+------------------------------
 Reporter:  luto@…      |       Type:  Bugs
   Status:  new         |  Milestone:  To Be Determined
Component:  None        |    Version:  Boost 1.54.0
 Severity:  Regression  |   Keywords:
------------------------+------------------------------
 {{{
 #include <functional>
 #include <boost/thread/once.hpp>

 using namespace std::placeholders;

 static int x = sizeof(_1);
 }}}

 The code above compiles in C++11 mode on boost 1.53, but it fails on boost
 1.54 like this:
 {{{
 boost_bind_bug.cpp:6:23: error: reference to ‘_1’ is ambiguous
  static int x = sizeof(_1);
                        ^
 In file included from boost_bind_bug.cpp:1:0:
 /usr/include/c++/4.8.2/functional:1004:34: note: candidates are: const
 std::_Placeholder<1> std::placeholders::_1
      extern const _Placeholder<1> _1;
                                   ^
 In file included from /usr/include/boost/bind/bind.hpp:1742:0,
                  from /usr/include/boost/bind.hpp:22,
                  from
 /usr/include/boost/thread/pthread/once_atomic.hpp:19,
                  from /usr/include/boost/thread/once.hpp:20,
                  from boost_bind_bug.cpp:2:
 /usr/include/boost/bind/placeholders.hpp:55:15: note:
 boost::arg<1> {anonymous}::_1
  boost::arg<1> _1;
                ^
 }}}

 This magic inclusion of boost/bind/placeholders.hpp is extremely impolite.

-- 
Ticket URL: <https://svn.boost.org/trac/boost/ticket/9508>
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