diff --git a/Modules/Core/Common/include/itkIndexRange.h b/Modules/Core/Common/include/itkIndexRange.h
index cab30acb746..e07399b3e93 100644
--- a/Modules/Core/Common/include/itkIndexRange.h
+++ b/Modules/Core/Common/include/itkIndexRange.h
@@ -294,12 +294,12 @@ class IndexRange final
 
   /** Constructs a range of indices for the specified grid size.
    */
-  explicit IndexRange(const SizeType& size)
+  explicit IndexRange(const SizeType& gridSize)
     :
     // Note: Use parentheses instead of curly braces to initialize data members,
     // to avoid AppleClang 6.0.0.6000056 compile errors, "no viable conversion..."
     m_MinIndex(),
-    m_MaxIndex(CalculateMaxIndex({}, size))
+    m_MaxIndex(CalculateMaxIndex({}, gridSize))
   {
   }
 
diff --git a/Modules/Core/Common/test/itkIndexRangeGTest.cxx b/Modules/Core/Common/test/itkIndexRangeGTest.cxx
index a0ae0028850..ef8d9937eb6 100644
--- a/Modules/Core/Common/test/itkIndexRangeGTest.cxx
+++ b/Modules/Core/Common/test/itkIndexRangeGTest.cxx
@@ -140,7 +140,7 @@ TEST(IndexRange, IteratorsCanBePassedToStdForEach)
 
   std::for_each(range.begin(), range.end(), [](const IndexType index)
   {
-    EXPECT_TRUE(index >= IndexType{});
+    EXPECT_TRUE(index >= IndexType());
   });
 }
 
@@ -155,7 +155,7 @@ TEST(IndexRange, CanBeUsedAsExpressionOfRangeBasedForLoop)
 
   for (auto&& index : range)
   {
-    EXPECT_TRUE(index >= IndexType{});
+    EXPECT_TRUE(index >= IndexType());
   }
 }