我正在尝试编译一些我在 Linux 中编写的软件，这些软件在我的 Mac 上使用了一些奇特的新 C++0x 功能。我使用 MacPorts 安装 gcc45 软件包，它给了我 /opt/local/bin/g++-mp-4.5，但是这个编译器不想编译
//test.cpp
#include <thread>
int main()
{
std::thread x;
return 0;
}
并获取：
bash-3.2$ /opt/local/bin/g++-mp-4.5 -std=c++0x test.cpp
test.cpp: In function 'int main()':
test.cpp:5:2: error: 'thread' is not a member of 'std'
test.cpp:5:14: error: expected ';' before 'x'
快速查看 /opt/local/include/gcc45/c++/thread 显示 std::thread 类已定义，但受以下内容保护：
#if defined(_GLIBCXX_HAS_GTHREADS) && defined(_GLIBCXX_USE_C99_STDINT_TR1)
再次，这在我的Ubuntu 机器，那么在 MacPorts 版本的 g++ 4.5 (g++-mp-4.5) 下启用 c++0x
更新：
看起来 SO 社区对此了解不多，所以也许是时候更接近开发人员了。有谁知道我可以将此问题转发到的官方邮件列表吗？有什么礼仪提示可以帮助我得到答案吗？
更新2：
我要求另一个临时解决方案这里，所以我现在只是用 boost::thread 库替换 std 库。不幸的是，没有 boost::future 所以这还不是一个完整的解决方案。任何帮助仍然将不胜感激。
I'm trying to compile some software I've been writing in Linux that uses some fancy new C++0x features on my Mac. I used MacPorts to install the gcc45 package, which gave me /opt/local/bin/g++-mp-4.5, however this compiler doesn't want to compile anything in <thread>. Eg I try to compile:
//test.cpp
#include <thread>
int main()
{
std::thread x;
return 0;
}
and get:
bash-3.2$ /opt/local/bin/g++-mp-4.5 -std=c++0x test.cpp
test.cpp: In function 'int main()':
test.cpp:5:2: error: 'thread' is not a member of 'std'
test.cpp:5:14: error: expected ';' before 'x'
A quick look in /opt/local/include/gcc45/c++/thread shows that the std::thread class is defined, but is guarded by the following:
#if defined(_GLIBCXX_HAS_GTHREADS) && defined(_GLIBCXX_USE_C99_STDINT_TR1)
Again, this works perfectly on my Ubuntu machine, so what's the proper way to enable the c++0x <thread> library under the MacPorts version of g++ 4.5 (g++-mp-4.5)? Failing that, is there anything I need to know (configure flags, etc.) before I go about compiling gcc 4.5 myself?
Update:
It doesn't look like the SO community knows much about this, so maybe it's time to go a little closer to the developers. Does anyone know of an official mailing list I could forward this question to? Are there any etiquette tips to help me get an answer?
Update 2:
I asked SO for another temporary solution here, and so I'm now just substituting the boost::thread libraries for the std ones. Unfortunately, there is no boost::future so this isn't quite a full solution yet. Any help would still be greatly appreciated.
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实际上
检查此功能的可用性>_POSIX_TIMEOUTS宏，但在 Mac OS X 10.4、10.5 和 10.6 中它被定义为-1（我不知道 10.7 是什么），并且这个函数在 pthread 中确实不存在.h。在 libstdc++ 配置期间检查
_POSIX_TIMEOUTS宏。如果检查成功结束，_GLIBCXX_HAS_GTHREADS宏将被定义。并且-std=c++0x使用。libstdc++ 确实需要
_POSIX_TIMEOUTS例如在std::timed_mutex类实现中（参见总而言之，我认为当 GCC 的 gthreads 或 libstdc++ 将实现 pthread_mutex_timedlock() （和其他）模拟或在 Mac OS X 中实现此函数时，
未来的 C++ 标准中可能会有一种方法来查询语言功能（例如，定时函数和类），并且可以在禁用此功能的情况下构建 libstdc++。但是我对未来的标准不太熟悉，并且对该功能存有疑问。
Actually
<thread>library doesn't work under Mac OS X because pthreads here don't have some functions with timeouts (e.g. pthread_mutex_timedlock()). Availability of this functions have to be checked using_POSIX_TIMEOUTSmacro but it's defined to-1in Mac OS X 10.4, 10.5 and 10.6 (I don't know what's about 10.7) and this functions are really absent inpthread.h.The
_POSIX_TIMEOUTSmacro is checked during the configuration of libstdc++. If the check ends successfully_GLIBCXX_HAS_GTHREADSmacro becomes defined. And<thread>contents become available with-std=c++0x.libstdc++ really needs
_POSIX_TIMEOUTSe.g. instd::timed_mutexclass implementation (see<mutex>header).To summarize, I think that
<thread>would become available on Mac OS X when GCC's gthreads or libstdc++ will implement pthread_mutex_timedlock() (and others) emulation or when this functions will be implemented in Mac OS X.Or maybe there would be a way in the future C++ standard to query for language features (e.g. this timed functions and classes) and it will be possible to build libstdc++ with this features disabled. However I'm not very familiar with the future standard and have doubts about that feature.
更新 - gcc4.7 现在允许在 OS X 上编译：参见此处
Update - gcc4.7 now allows compilation of on OS X: See here