diff --git a/Code/UtilitiesAdapters/OGRAdapters/otbOGRDataSourceWrapper.txx b/Code/UtilitiesAdapters/OGRAdapters/otbOGRDataSourceWrapper.txx
index 9843afa5eff022e68984cf7885af4118334acfe6..5f336bab58b9824943bd9fccbc22a30e4b0a9a30 100644
--- a/Code/UtilitiesAdapters/OGRAdapters/otbOGRDataSourceWrapper.txx
+++ b/Code/UtilitiesAdapters/OGRAdapters/otbOGRDataSourceWrapper.txx
@@ -112,7 +112,7 @@ template <class Value>
 void otb::ogr::DataSource::layer_iter<Value>::increment()
 {
   assert(m_DataSource
-    && m_index < m_DataSource->GetLayersCount()
+    && int(m_index) < m_DataSource->GetLayersCount()
     && "cannot increment past end()");
   ++m_index;
 }
@@ -121,7 +121,7 @@ template <class Value>
 Value otb::ogr::DataSource::layer_iter<Value>::dereference() const
 {
   assert(m_DataSource
-    && m_index < m_DataSource->GetLayersCount()
+    && int(m_index) < m_DataSource->GetLayersCount()
     && "cannot dereference past end()");
   return Value(m_DataSource->GetLayerUnchecked(m_index));
 }