Hi I'm trying to use the the boost::thread::mutex class in a Windows 95 project. Since the generated .lib files for the thread library include InterlockedCompareExchange (used in try_mutex::call_once) I was left with the option of adding the mutex.cpp and the exceptions.cpp files to my project and compiling them separately. Building the program included at the end, MSCV 7.1 gives the following linker errors: Compiling... Mutex.cpp Linking... mutex1.obj : error LNK2019: unresolved external symbol "void __cdecl boost::call_once(void (__cdecl*)(void),long &)" (?call_once@boost@@YAXP6AXXZAAJ@Z) referenced in function "bool __cdecl `anonymous namespace'::has_TryEnterCriticalSection(void)" (?has_TryEnterCriticalSection@?A0x5deb84cd@@YA_NXZ) mutex1.obj : error LNK2019: unresolved external symbol "int __cdecl boost::xtime_get(struct boost::xtime *,int)" (?xtime_get@boost@@YAHPAUxtime@1@H@Z) referenced in function "private: bool __thiscall boost::timed_mutex::do_timedlock(struct boost::xtime const &)" (?do_timedlock@timed_mutex@boost@@AAE_NABUxtime@2@@Z) Debug/Mutex.exe : fatal error LNK1120: 2 unresolved externals call_once is called in try_mutex constructor, while xtime_get is called in timed_mutex::do_timedlock. Nor try_mutex or timed_mutex are used at all. This was confirmed by commenting out the whole implementation for both in mutex.cpp, in which case the program links without problems. Just commenting out the lines m_critical_section = has_TryEnterCriticalSection(); in the try_mutex constructor and boost::xtime_get(&cur, boost::TIME_UTC); in timed_mutex::do_timedlock makes the program link. I originally expected the linker will remove all try_mutex and timed_muted implementation but it does not. Can someone give any ideas on how to use boost::mutex in a MSCV 7.1 project for Windows 95 without having to modify the original files? Is there a reason for the linker not to remove all the code for try_mutex and timed_mutex? Thanks in advance. Best regards Jorge #define BOOST_THREAD_NO_LIB #include <boost/thread/mutex.hpp> // mutex.cpp and exceptions.cpp compiled with // BOOST_THREAD_NO_LIB preprocessor option. // This must be enforced, since they both #include // <boost/thread/detail/config.hpp> int main(int argc, char *argv[ ]) { boost::mutex mymutex; boost::mutex::scoped_lock scoped_lock(mymutex); }