diff --git a/test/product_mmtr.cpp b/test/product_mmtr.cpp
index 92e6b668f..ecb5c36a3 100644
--- a/test/product_mmtr.cpp
+++ b/test/product_mmtr.cpp
@@ -25,8 +25,8 @@ template<typename Scalar> void mmtr(int size)
 
   DenseIndex othersize = internal::random<DenseIndex>(1,200);
   
-  MatrixColMaj matc(size, size);
-  MatrixRowMaj matr(size, size);
+  MatrixColMaj matc = MatrixColMaj::Zero(size, size);
+  MatrixRowMaj matr = MatrixRowMaj::Zero(size, size);
   MatrixColMaj ref1(size, size), ref2(size, size);
   
   MatrixColMaj soc(size,othersize); soc.setRandom();