add accessors to coeff based product

Eigen/src/Core/products/CoeffBasedProduct.h

@@ -182,6 +182,9 @@ class CoeffBasedProduct
       return m_result;
     }
 
+    const _LhsNested& lhs() const { return m_lhs; }
+    const _RhsNested& rhs() const { return m_rhs; }
+
   protected:
     const LhsNested m_lhs;
     const RhsNested m_rhs;

test/product_notemporary.cpp

@@ -25,7 +25,7 @@
 static int nb_temporaries;
 
 #define EIGEN_DEBUG_MATRIX_CTOR { \
-    if(SizeAtCompileTime==Dynamic) \
+    if(SizeAtCompileTime==Dynamic && this->data()!=0) \
       nb_temporaries++; \
  }