diff --git a/src/tests/range_unit_test.cc b/src/tests/range_unit_test.cc
index 0f68311..9cc4748 100644
--- a/src/tests/range_unit_test.cc
+++ b/src/tests/range_unit_test.cc
@@ -263,8 +263,8 @@ namespace
 	EXPECT_EQ(yi.pos(), yi.pmax());
 
 	yi -= yi.lmax() + 20;
-	EXPECT_EQ(yi.lex(), 0);
-	EXPECT_EQ(yi.pos(), 0);
+	EXPECT_EQ(yi.lex(), 0u);
+	EXPECT_EQ(yi.pos(), 0u);
     }
     // RCast_Test
 }