diff --git a/test/test_util.h b/test/test_util.h
index d44b939ebd..9d7631f90b 100644
--- a/test/test_util.h
+++ b/test/test_util.h
@@ -1140,6 +1140,7 @@ struct NumericTraits<TestFoo>
 // Complex data type TestBar (with optimizations for fence-free warp-synchrony)
 //---------------------------------------------------------------------
 
+#define MAGIC 895245
 /**
  * TestBar complex data type
  */
@@ -1147,22 +1148,33 @@ struct TestBar
 {
     long long       x;
     int             y;
+    int             magic;
 
     // Constructor
-    __host__ __device__ __forceinline__ TestBar() : x(0), y(0)
+    __host__ __device__ __forceinline__ TestBar() : x(0), y(0), magic(MAGIC)
     {}
 
     // Constructor
-    __host__ __device__ __forceinline__ TestBar(int b) : x(b), y(b)
+    __host__ __device__ __forceinline__ TestBar(int b) : x(b), y(b), magic(MAGIC)
     {}
 
     // Constructor
-    __host__ __device__ __forceinline__ TestBar(long long x, int y) : x(x), y(y)
+    __host__ __device__ __forceinline__ TestBar(long long x, int y) : x(x), y(y), magic(MAGIC)
     {}
 
+    // Assignment operator
+    __host__ __device__ __forceinline__ TestBar& operator =(const TestBar& that)
+    {
+        assert (magic == MAGIC);
+        x = that.x;
+        y = that.y;
+        return *this;
+    }
+
     // Assignment from int operator
     __host__ __device__ __forceinline__ TestBar& operator =(int b)
     {
+        assert (magic == MAGIC);
         x = b;
         y = b;
         return *this;