diff --git a/test/openpower-pels/mtms_test.cpp b/test/openpower-pels/mtms_test.cpp
index b9c0929..b0f0130 100644
--- a/test/openpower-pels/mtms_test.cpp
+++ b/test/openpower-pels/mtms_test.cpp
@@ -32,12 +32,12 @@
 
         MTMS mtms{tm, sn};
 
-        std::array<uint8_t, 8> t{'T', 'T', 'T', 'T', '-', 'M', 'M', 'M'};
+        const std::array<uint8_t, 8> t{'T', 'T', 'T', 'T', '-', 'M', 'M', 'M'};
         EXPECT_EQ(t, mtms.machineTypeAndModelRaw());
         EXPECT_EQ("TTTT-MMM", mtms.machineTypeAndModel());
 
-        std::array<uint8_t, 12> s{'1', '2', '3', '4', '5', '6',
-                                  '7', '8', '9', 'A', 'B', 'C'};
+        const std::array<uint8_t, 12> s{'1', '2', '3', '4', '5', '6',
+                                        '7', '8', '9', 'A', 'B', 'C'};
         EXPECT_EQ(s, mtms.machineSerialNumberRaw());
         EXPECT_EQ("123456789ABC", mtms.machineSerialNumber());
     }
@@ -49,11 +49,11 @@
 
         MTMS mtms{tm, sn};
 
-        std::array<uint8_t, 8> t{'T', 'T', 'T', 'T', '-', 'M', 'M', 'M'};
+        const std::array<uint8_t, 8> t{'T', 'T', 'T', 'T', '-', 'M', 'M', 'M'};
         EXPECT_EQ(t, mtms.machineTypeAndModelRaw());
 
-        std::array<uint8_t, 12> s{'1', '2', '3', '4', '5', '6',
-                                  '7', '8', '9', 'A', 'B', 'C'};
+        const std::array<uint8_t, 12> s{'1', '2', '3', '4', '5', '6',
+                                        '7', '8', '9', 'A', 'B', 'C'};
         EXPECT_EQ(s, mtms.machineSerialNumberRaw());
     }
 
@@ -64,11 +64,12 @@
 
         MTMS mtms{tm, sn};
 
-        std::array<uint8_t, 8> t{'T', 'T', 'T', 'T', 0, 0, 0, 0};
+        const std::array<uint8_t, 8> t{'T', 'T', 'T', 'T', 0, 0, 0, 0};
         EXPECT_EQ(t, mtms.machineTypeAndModelRaw());
         EXPECT_EQ("TTTT", mtms.machineTypeAndModel());
 
-        std::array<uint8_t, 12> s{'1', '2', '3', '4', 0, 0, 0, 0, 0, 0, 0, 0};
+        const std::array<uint8_t, 12> s{'1', '2', '3', '4', 0, 0,
+                                        0,   0,   0,   0,   0, 0};
         EXPECT_EQ(s, mtms.machineSerialNumberRaw());
         EXPECT_EQ("1234", mtms.machineSerialNumber());
     }