diff --git a/include/chaiscript/chaiscript_threading.hpp b/include/chaiscript/chaiscript_threading.hpp
index 22c3301..f0be3f0 100644
--- a/include/chaiscript/chaiscript_threading.hpp
+++ b/include/chaiscript/chaiscript_threading.hpp
@@ -8,7 +8,16 @@
 #define CHAISCRIPT_THREADING_HPP_
 
 #ifndef CHAISCRIPT_NO_THREADS
+
+#ifdef __llvm__
+#pragma clang diagnostic push
+#pragma clang diagnostic ignored "-Wc++11-long-long"
+#pragma clang diagnostic ignored "-Wshadow"
+#endif
 #include <boost/thread.hpp>
+#ifdef __llvm__
+#pragma clang diagnostic pop
+#endif
 #else
 #pragma message ("ChaiScript is compiling without thread safety.")
 #endif
diff --git a/include/chaiscript/dispatchkit/boxed_value.hpp b/include/chaiscript/dispatchkit/boxed_value.hpp
index 59f777e..14e0530 100644
--- a/include/chaiscript/dispatchkit/boxed_value.hpp
+++ b/include/chaiscript/dispatchkit/boxed_value.hpp
@@ -13,7 +13,19 @@
 
 #include <map>
 #include <boost/shared_ptr.hpp>
+
+#ifdef __llvm__
+#pragma clang diagnostic push
+#pragma clang diagnostic ignored "-Wshadow"
+#pragma clang diagnostic ignored "-Wunused-parameter"
+#endif
+
 #include <boost/make_shared.hpp>
+
+#ifdef __llvm__
+#pragma clang diagnostic pop
+#endif
+
 #include <boost/any.hpp>
 #include <boost/function.hpp>
 #include <boost/ref.hpp>
diff --git a/include/chaiscript/dispatchkit/exception_specification.hpp b/include/chaiscript/dispatchkit/exception_specification.hpp
index 7770d11..b1fa687 100644
--- a/include/chaiscript/dispatchkit/exception_specification.hpp
+++ b/include/chaiscript/dispatchkit/exception_specification.hpp
@@ -17,6 +17,8 @@ namespace chaiscript
     {
       virtual void handle(const Boxed_Value &bv, const Dispatch_Engine &t_engine) = 0;
 
+      virtual ~Exception_Handler_Base() {}
+
       protected:
         template<typename T>
         void throw_type(const Boxed_Value &bv, const Dispatch_Engine &t_engine)
@@ -28,6 +30,8 @@ namespace chaiscript
     template<typename T1>
       struct Exception_Handler_Impl1 : Exception_Handler_Base
       {
+        virtual ~Exception_Handler_Impl1() {}
+
         virtual void handle(const Boxed_Value &bv, const Dispatch_Engine &t_engine)
         {
           throw_type<T1>(bv, t_engine);
@@ -36,6 +40,8 @@ namespace chaiscript
     template<typename T1, typename T2>
       struct Exception_Handler_Impl2 : Exception_Handler_Base
       {
+        virtual ~Exception_Handler_Impl2() {}
+
         virtual void handle(const Boxed_Value &bv, const Dispatch_Engine &t_engine)
         {
           throw_type<T1>(bv, t_engine);
@@ -46,6 +52,8 @@ namespace chaiscript
     template<typename T1, typename T2, typename T3>
       struct Exception_Handler_Impl3 : Exception_Handler_Base
       {
+        virtual ~Exception_Handler_Impl3() {}
+
         virtual void handle(const Boxed_Value &bv, const Dispatch_Engine &t_engine)
         {
           throw_type<T1>(bv, t_engine);
@@ -56,6 +64,8 @@ namespace chaiscript
     template<typename T1, typename T2, typename T3, typename T4>
       struct Exception_Handler_Impl4 : Exception_Handler_Base
       {
+        virtual ~Exception_Handler_Impl4() {}
+
         virtual void handle(const Boxed_Value &bv, const Dispatch_Engine &t_engine)
         {
           throw_type<T1>(bv, t_engine);
@@ -67,6 +77,8 @@ namespace chaiscript
     template<typename T1, typename T2, typename T3, typename T4, typename T5>
       struct Exception_Handler_Impl5 : Exception_Handler_Base
       {
+        virtual ~Exception_Handler_Impl5() {}
+
         virtual void handle(const Boxed_Value &bv, const Dispatch_Engine &t_engine)
         {
           throw_type<T1>(bv, t_engine);
diff --git a/include/chaiscript/dispatchkit/proxy_functions_detail.hpp b/include/chaiscript/dispatchkit/proxy_functions_detail.hpp
index 7ae0955..fb7980a 100644
--- a/include/chaiscript/dispatchkit/proxy_functions_detail.hpp
+++ b/include/chaiscript/dispatchkit/proxy_functions_detail.hpp
@@ -86,9 +86,16 @@ namespace chaiscript
        * if any unboxing fails the execution of the function fails and
        * the bad_boxed_cast is passed up to the caller.
        */
+#ifdef __llvm__
+#pragma clang diagnostic push
+#pragma clang diagnostic ignored "-Wunused-parameter"
+#endif
       template<typename Ret BOOST_PP_COMMA_IF(n) BOOST_PP_ENUM_PARAMS(n, typename Param)>
         Ret call_func(const boost::function<Ret (BOOST_PP_ENUM_PARAMS(n, Param))> &f,
-            const std::vector<Boxed_Value> &params, const Dynamic_Cast_Conversions & BOOST_PP_IF(n, t_conversions, ))
+            const std::vector<Boxed_Value> &params, const Dynamic_Cast_Conversions & BOOST_PP_IF(n, t_conversions, BOOST_PP_EMPTY))
+#ifdef __llvm__
+#pragma clang diagnostic pop
+#endif
         {
           if (params.size() != n)
           {
@@ -103,9 +110,17 @@ namespace chaiscript
        * Proxy_Function_Impl object. This function is primarly used to prevent
        * registration of two functions with the exact same signatures
        */
-      template<typename Ret BOOST_PP_COMMA_IF(n) BOOST_PP_ENUM_PARAMS(n, typename Param)>
+
+#ifdef __llvm__
+#pragma clang diagnostic push
+#pragma clang diagnostic ignored "-Wunused-parameter"
+#endif
+       template<typename Ret BOOST_PP_COMMA_IF(n) BOOST_PP_ENUM_PARAMS(n, typename Param)>
         bool compare_types_cast(Ret (*)(BOOST_PP_ENUM_PARAMS(n, Param)),
-            const std::vector<Boxed_Value> & BOOST_PP_IF(n, params, ), const Dynamic_Cast_Conversions &t_conversions)
+            const std::vector<Boxed_Value> & BOOST_PP_IF(n, params, BOOST_PP_EMPTY), const Dynamic_Cast_Conversions &t_conversions)
+#ifdef __llvm__
+#pragma clang diagnostic pop
+#endif
         {
           try {
             (void)t_conversions;
diff --git a/include/chaiscript/language/chaiscript_engine.hpp b/include/chaiscript/language/chaiscript_engine.hpp
index b21cfd2..32d9e32 100644
--- a/include/chaiscript/language/chaiscript_engine.hpp
+++ b/include/chaiscript/language/chaiscript_engine.hpp
@@ -420,19 +420,20 @@ namespace chaiscript
         try {
           const std::string appendedpath = m_usepaths[i] + t_filename;
 
-          chaiscript::detail::threading::lock_guard<chaiscript::detail::threading::recursive_mutex> l(m_use_mutex);
-          chaiscript::detail::threading::shared_lock<chaiscript::detail::threading::shared_mutex> l2(m_mutex);
+          chaiscript::detail::threading::unique_lock<chaiscript::detail::threading::recursive_mutex> l(m_use_mutex);
+          chaiscript::detail::threading::unique_lock<chaiscript::detail::threading::shared_mutex> l2(m_mutex);
 
           if (m_used_files.count(appendedpath) == 0)
           {
-            m_used_files.insert(appendedpath);
             l2.unlock();
             eval_file(appendedpath);
-          }
+            l2.lock();
+            m_used_files.insert(appendedpath);
+           }
 
           return; // return, we loaded it, or it was already loaded
         } catch (const exception::file_not_found_error &) {
-          if (i == m_usepaths.size() - 1)
+           if (i == m_usepaths.size() - 1)
           {
             throw exception::file_not_found_error(t_filename);
           }
diff --git a/samples/example.cpp b/samples/example.cpp
index 0164638..086f60d 100644
--- a/samples/example.cpp
+++ b/samples/example.cpp
@@ -9,7 +9,18 @@
 #include <chaiscript/chaiscript.hpp>
 #include <chaiscript/dispatchkit/function_call.hpp>
 #include <boost/function.hpp>
+
+#ifdef __llvm__
+#pragma clang diagnostic push
+#pragma clang diagnostic ignored "-Wunused-parameter"
+#endif
+
 #include <boost/date_time/posix_time/posix_time.hpp>
+
+#ifdef __llvm__
+#pragma clang diagnostic pop
+#endif
+
 #include <boost/regex.hpp>
 
 void log(const std::string &msg)
diff --git a/src/reflection.cpp b/src/reflection.cpp
index 2027c47..71408e2 100644
--- a/src/reflection.cpp
+++ b/src/reflection.cpp
@@ -42,6 +42,12 @@ chaiscript::AST_NodePtr get_parse_tree(const chaiscript::Const_Proxy_Function &t
 }
 
 
+#ifdef __llvm__
+#pragma clang diagnostic push
+#pragma clang diagnostic ignored "-Wreturn-type-c-linkage"
+#endif
+
+
 CHAISCRIPT_MODULE_EXPORT  chaiscript::ModulePtr create_chaiscript_module_reflection()
 {
   chaiscript::ModulePtr m(new chaiscript::Module());
@@ -90,6 +96,11 @@ CHAISCRIPT_MODULE_EXPORT  chaiscript::ModulePtr create_chaiscript_module_reflect
   return m;
 }
 
+#ifdef __llvm__
+#pragma clang diagnostic pop
+#endif
+
+
 
 #ifdef BOOST_MSVC
 #pragma warning(pop)
diff --git a/src/stl_extra.cpp b/src/stl_extra.cpp
index 59a542a..2045fe9 100644
--- a/src/stl_extra.cpp
+++ b/src/stl_extra.cpp
@@ -10,11 +10,19 @@
 #pragma warning(disable : 4190)
 #endif
 
+#ifdef __llvm__
+#pragma clang diagnostic push
+#pragma clang diagnostic ignored "-Wreturn-type-c-linkage"
+#endif
+
 CHAISCRIPT_MODULE_EXPORT chaiscript::ModulePtr create_chaiscript_module_stl_extra()
 {
   return chaiscript::bootstrap::standard_library::list_type<std::list<chaiscript::Boxed_Value> >("List");
 }
 
+#ifdef __llvm__
+#pragma clang diagnostic pop
+#endif
 
 #ifdef BOOST_MSVC
 #pragma warning(pop)
diff --git a/src/test_module.cpp b/src/test_module.cpp
index 313d29a..df68b58 100644
--- a/src/test_module.cpp
+++ b/src/test_module.cpp
@@ -49,6 +49,10 @@ int *get_new_int()
 #pragma warning(disable : 4190)
 #endif
 
+#ifdef __llvm__
+#pragma clang diagnostic push
+#pragma clang diagnostic ignored "-Wreturn-type-c-linkage"
+#endif
 
 CHAISCRIPT_MODULE_EXPORT  chaiscript::ModulePtr create_chaiscript_module_test_module()
 {
@@ -86,6 +90,10 @@ CHAISCRIPT_MODULE_EXPORT  chaiscript::ModulePtr create_chaiscript_module_test_mo
 }
 
 
+#ifdef __llvm__
+#pragma clang diagnostic pop
+#endif
+
 #ifdef BOOST_MSVC
 #pragma warning(pop)
 #endif
diff --git a/unittests/multithreaded_test.cpp b/unittests/multithreaded_test.cpp
index 0814bb6..731a4ff 100644
--- a/unittests/multithreaded_test.cpp
+++ b/unittests/multithreaded_test.cpp
@@ -25,13 +25,17 @@ int expected_value(int num_iters)
 
 void do_work(chaiscript::ChaiScript &c, int id)
 {
-  std::stringstream ss;
-  ss << "MyVar" << rand();
-  c.add(chaiscript::var(5), ss.str());
-  ss.str("");
-  ss << id;
-  c.use("multithreaded_work.inc");
-  c("do_chai_work(4000, " + ss.str() + ");");
+  try{
+    std::stringstream ss;
+    ss << "MyVar" << rand();
+    c.add(chaiscript::var(5), ss.str());
+    ss.str("");
+    ss << id;
+    c.use("multithreaded_work.inc");
+    c("do_chai_work(4000, " + ss.str() + ");");
+  } catch (const std::exception &e) {
+    std::cout << "exception: " << e.what() << " thread:  " << id;
+  }
 }
 
 int main()
@@ -65,20 +69,17 @@ int main()
 
   chaiscript::ChaiScript chai(modulepaths,usepaths);
 
-  std::vector<boost::shared_ptr<boost::thread> > threads;
+  boost::thread_group threads;
 
   // Ensure at least two, but say only 7 on an 8 core processor
   int num_threads = std::max<unsigned int>(boost::thread::hardware_concurrency() - 1, 2u);
 
   for (int i = 0; i < num_threads; ++i)
   {
-    threads.push_back(boost::shared_ptr<boost::thread>(new boost::thread(boost::bind(do_work, boost::ref(chai), i))));
+    threads.create_thread(boost::bind(&do_work, boost::ref(chai), i));
   }
 
-  for (int i = 0; i < num_threads; ++i)
-  {
-    threads[i]->join();
-  }
+  threads.join_all();
 
 
   for (int i = 0; i < num_threads; ++i)