c++ - Boost upgrade_to_unique_lock 编译错误

Question

我正在使用 Boost.Thread 编写应用程序。不幸的是，将新版本移至“生产”环境后，我无法编译该项目。 g++ 说:

/usr/include/boost/thread/locks.hpp: In constructor 
    ‘boost::upgrade_to_unique_lock<Mutex>::upgrade_to_unique_lock
    (boost::upgrade_lock<Mutex>&) [with Mutex = boost::shared_mutex]’:
worker.cpp:34:69: instantiated from here
/usr/include/boost/thread/locks.hpp:926:48: error: call of overloaded ‘move(
    boost::upgrade_lock<boost::shared_mutex>&)’ is ambiguous
/usr/include/boost/thread/locks.hpp:926:48: note: candidates are:
/usr/include/boost/move/move.hpp:294:86: note: typename boost::move_detail
    ::disable_if<boost::has_move_emulation_enabled<T>, T&>::type boost::move(T&)
    [with T = boost::upgrade_lock<boost::shared_mutex>, typename boost::move_detail
    ::disable_if<boost::has_move_emulation_enabled<T>, T&>::type = boost
    ::upgrade_lock<boost::shared_mutex>&]
/usr/include/boost/thread/detail/move.hpp:44:110: note: typename boost
    ::enable_if<boost::is_convertible<T&, boost::detail::thread_move_t<T> >,
    boost::detail::thread_move_t<T> >::type boost::move(T&) [with T = boost
    ::upgrade_lock<boost::shared_mutex>, typename boost::enable_if<boost
    ::is_convertible<T&, boost::detail::thread_move_t<T> >, boost::detail
    ::thread_move_t<T> >::type = boost::detail::thread_move_t<boost
    ::upgrade_lock<boost::shared_mutex> >]
/usr/include/boost/thread/locks.hpp: In destructor ‘boost::upgrade_to_unique_lock
    <Mutex>::~upgrade_to_unique_lock() [with Mutex = boost::shared_mutex]’:
worker.cpp:34:69: instantiated from here
/usr/include/boost/thread/locks.hpp:932:17: error: call of overloaded ‘move(boost
    ::unique_lock<boost::shared_mutex>&)’ is ambiguous
...

等等等等。

我检查了开发环境和生产环境是否具有相同的 libboost 版本 (1.48)。

有谁知道可能是什么原因？我应该检查/升级哪些其他库/工具版本？

Answer 1

这是 Boost 1.48 中的一个已知错误，根据 their bug tracker 似乎已在 1.49 中修复.如果将模拟 C++11 移动语义的 Boost.Move 与带有自己的移动语义模拟器的 Boost.Thread 一起使用，则存在歧义。

考虑到 Boost 1.48 已发布超过 2.5 年(在 November 2011 中)，您应该考虑升级到最新版本，目前是 Boost 1.55。