diff --git a/src/Generator/Passes/CheckDuplicatedNamesPass.cs b/src/Generator/Passes/CheckDuplicatedNamesPass.cs
index f1fe437f..7316ca64 100644
--- a/src/Generator/Passes/CheckDuplicatedNamesPass.cs
+++ b/src/Generator/Passes/CheckDuplicatedNamesPass.cs
@@ -44,7 +44,9 @@ namespace CppSharp.Passes
 
         private bool UpdateName(Function function)
         {
-            Generator.CurrentOutputNamespace = function.TranslationUnit.Module.OutputNamespace;
+            if (function.TranslationUnit.Module != null)
+                Generator.CurrentOutputNamespace = function.TranslationUnit.Module.OutputNamespace;
+
             var @params = function.Parameters.Where(p => p.Kind != ParameterKind.IndirectReturnType)
                                 .Select(p => p.QualifiedType.ToString());
             // Include the conversion type in case of conversion operators