Fixed the code generation for indexers returning a void pointer (#901)

src/Generator/Passes/CheckOperatorsOverloads.cs

@@ -101,7 +101,8 @@ namespace CppSharp.Passes
                 };
 
             var returnType = @operator.Type;
-            if (returnType.IsAddress())
+            if (returnType.IsAddress() &&
+                !returnType.GetQualifiedPointee().Type.Desugar().IsPrimitiveType(PrimitiveType.Void))
             {
                 var pointer = (PointerType) returnType;
                 var qualifiedPointee = pointer.QualifiedPointee;

tests/CSharp/CSharp.Tests.cs

@@ -844,4 +844,14 @@ public unsafe class CSharpTests : GeneratorTestFixture
             Assert.That(indexproperty[&a], Is.EqualTo(2));
         }
     }
+
+    [Test]
+    public void TestVoidPtrReturningIndexer()
+    {
+        using (var indexproperty = new TestIndexedProperties())
+        {
+            uint n = 21;
+            Assert.That(*((int*) indexproperty[n]), Is.EqualTo(21));
+        }
+    }
 }

tests/CSharp/CSharp.h

@@ -1198,7 +1198,9 @@ struct HasComplexArray
 class DLL_API TestIndexedProperties
 {
 public:
+    mutable int field;
     int operator[](const int& key);
+    void* operator[](size_t n) const;
 };
 
 int TestIndexedProperties::operator[](const int& key)
@@ -1206,6 +1208,12 @@ int TestIndexedProperties::operator[](const int& key)
     return key;
 }
 
+void* TestIndexedProperties::operator[](size_t n) const
+{
+    field = n;
+    return &field;
+}
+
 extern const ComplexArrayElement ArrayOfVariableSize[];
 
 void useStdStringJustAsParameter(std::string s);