Fixing windows build issues

Signed-off-by: Matthew A Johnson <matjoh@microsoft.com>

Author: matajoh

PCbuild/_freeze_module.vcxproj

@@ -208,6 +208,7 @@
     <ClCompile Include="..\Python\hashtable.c" />
     <ClCompile Include="..\Python\import.c" />
     <ClCompile Include="..\Python\importdl.c" />
+    <ClCompile Include="..\Python\immutability.c" />
     <ClCompile Include="..\Python\initconfig.c" />
     <ClCompile Include="..\Python\intrinsics.c" />
     <ClCompile Include="..\Python\instrumentation.c" />

PCbuild/_freeze_module.vcxproj.filters

@@ -208,6 +208,9 @@
     <ClCompile Include="..\Python\importdl.c">
       <Filter>Source Files</Filter>
     </ClCompile>
+    <CLCompile Include="..\Python\immutability.c">
+      <Filter>Source Files</Filter>
+    </CLCompile>
     <ClCompile Include="..\Python\initconfig.c">
       <Filter>Source Files</Filter>
     </ClCompile>

Python/immutability.c

@@ -454,12 +454,12 @@ bool _Py_GlobalsImmutable_Check()
 
     main = PyInterpreterState_Main();
     if(main == NULL){
-        return NULL;
+        return false;
     }
 
     main_dict = PyInterpreterState_GetDict(main);
     if(main_dict == NULL){
-        return NULL;
+        return false;
     }
 
     flag = PyDict_GetItemString(main_dict, "__globals_immutable__");