- Fix legit threading issue which shows itself on clang / macos mostly

- Fix all warnings that I can / ignore those caused by boost

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)