diff --git a/CMakeLists.txt b/CMakeLists.txt
index e98ed1d7..2b210467 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -174,6 +174,8 @@ if(MSVC)
     add_definitions(/std:c++17)
   endif()
 
+
+
   if (MSVC_VERSION STREQUAL "1800")
     # VS2013 doesn't have magic statics
     add_definitions(/w44640)
@@ -182,7 +184,7 @@ if(MSVC)
     add_definitions(/w34062)
   endif()
 
-  add_definitions(/bigobj)
+  add_definitions(/bigobj /permissive-)
   # Note on MSVC compiler flags.
   # The code base selective disables warnings as necessary when the compiler is complaining too much
   # about something that is perfectly valid, or there is simply no technical way around it
diff --git a/include/chaiscript/language/chaiscript_eval.hpp b/include/chaiscript/language/chaiscript_eval.hpp
index e0933b71..e5b2aa7e 100644
--- a/include/chaiscript/language/chaiscript_eval.hpp
+++ b/include/chaiscript/language/chaiscript_eval.hpp
@@ -327,15 +327,17 @@ namespace chaiscript
 
           Boxed_Value fn(this->children[0]->eval(t_ss));
 
+          using ConstFunctionTypePtr = const dispatch::Proxy_Function_Base *;
           try {
-            return (*t_ss->boxed_cast<const dispatch::Proxy_Function_Base *>(fn))(params, t_ss.conversions());
+            return (*t_ss->boxed_cast<ConstFunctionTypePtr>(fn))(params, t_ss.conversions());
           }
           catch(const exception::dispatch_error &e){
             throw exception::eval_error(std::string(e.what()) + " with function '" + this->children[0]->text + "'", e.parameters, e.functions, false, *t_ss);
           }
           catch(const exception::bad_boxed_cast &){
             try {
-              Const_Proxy_Function f = t_ss->boxed_cast<const Const_Proxy_Function &>(fn);
+              using ConstFunctionTypeRef = const Const_Proxy_Function &;
+              Const_Proxy_Function f = t_ss->boxed_cast<ConstFunctionTypeRef>(fn);
               // handle the case where there is only 1 function to try to call and dispatch fails on it
               throw exception::eval_error("Error calling function '" + this->children[0]->text + "'", params, {f}, false, *t_ss);
             } catch (const exception::bad_boxed_cast &) {