Re: VC++ still not linking

From: bill_kempf (williamkempf_at_[hidden])
Date: 2002-05-17 10:29:12

--- In Boost-Users_at_y..., "imi123_1999" <imi123_1999_at_y...> wrote:
> This is my second post. In the last post i pointed out two errors 
out 
> of which one is fixed but the other one is still there. 
> 
> I am trying to build a sample program on threads in VC++. It 
compiles 
> successfully but the linker gives errors of unresolved external 
> symbols. Please tell me that what "changes" we've to make in VC++ 6 
> linker options. Please tell me clearly that in which dialog box of 
> VC++ IDE we have to make changes and how and what changes we've to 
> made. I am using boost 1_27_0. Program and errors are given below:
> 
> ********************************************************
> 
> The program is:
> 
> #include <boost/thread/thread.hpp>
> #include <iostream>
> 
> int count = 0;
> boost::mutex mutex;
> 
> void increment_count()
> {
>    boost::mutex::scoped_lock lock(mutex);
>    std::cout << "count = " << ++count << std::endl;
> }
> 
> int main(int argc, char* argv[])
> {
>    boost::thread_group threads;
>    for (int i = 0; i < 10; ++i)
>       threads.create_thread(&increment_count);
>    threads.join_all();
> }
> 
> 
> 
> ********************************************************
> The errors i am getting are: 
> 
> imi.obj : error LNK2001: unresolved external symbol "public: 
> __thiscall boost::mutex::mutex(void)" (??0mutex_at_boost@@QAE_at_XZ)
> 
> imi.obj : error LNK2001: unresolved external symbol "public: 
> __thiscall boost::mutex::~mutex(void)" (??1mutex_at_boost@@QAE_at_XZ)
> 
> imi.obj : error LNK2001: unresolved external symbol "public: 
> __thiscall boost::thread_group::~thread_group(void)" (??
> 1thread_group_at_boost@@QAE_at_XZ)
> 
> imi.obj : error LNK2001: unresolved external symbol "public: void 
> __thiscall boost::thread_group::join_all(void)" (?
> join_all_at_thread_group_at_boost@@QAEXXZ)
> 
> imi.obj : error LNK2001: unresolved external symbol "public: class 
> boost::thread * __thiscall boost::thread_group::create_thread(class 
> boost::function0<void,struct boost::empty_function_policy,struct 
> boost::empty_function_mixin,int> const &)" (?crea
> te_thread_at_thread_group_at_boost@@QAEPAVthread_at_2@ABV?
> 
$function0_at_XUempty_function_policy_at_boost@@Uempty_function_mixin_at_2@H_at_2@
> @Z)
> 
> imi.obj : error LNK2001: unresolved external symbol "public: 
> __thiscall boost::thread_group::thread_group(void)" (??
> 0thread_group_at_boost@@QAE_at_XZ)
> 
> imi.obj : error LNK2001: unresolved external symbol "public: 
> __thiscall boost::lock_error::lock_error(void)" (??
> 0lock_error_at_boost@@QAE_at_XZ)
> 
> 
> imi.obj : error LNK2001: unresolved external symbol "private: void 
> __thiscall boost::mutex::do_lock(void)" (?
do_lock_at_mutex@boost@@AAEXXZ)
> 
> imi.obj : error LNK2001: unresolved external symbol "private: void 
> __thiscall boost::mutex::do_unlock(void)" (?
> do_unlock_at_mutex@boost@@AAEXXZ)
> 
> Debug/threadImI.exe : fatal error LNK1120: 9 unresolved externals
> Error executing link.exe.
> 
> threadImI.exe - 10 error(s), 0 warning(s)

Have you linked against libboost_thread.lib and boost_threadmon.dll?

Bill Kempf