diff --git a/Eigen/src/Core/MapBase.h b/Eigen/src/Core/MapBase.h
index fe61d2a28..0d85085c8 100644
--- a/Eigen/src/Core/MapBase.h
+++ b/Eigen/src/Core/MapBase.h
@@ -160,6 +160,8 @@ template<typename Derived> class MapBase<Derived, ReadOnlyAccessors>
     EIGEN_DEVICE_FUNC
     void checkSanity() const
     {
+      eigen_assert(EIGEN_IMPLIES(internal::packet_traits<Scalar>::AlignedOnScalar, (size_t(m_data) % sizeof(Scalar)) == 0)
+                   && "input pointer is not aligned on scalar boundary, e.g., use \"EIGEN_ALIGN8 T ptr[N];\" for double or complex<float>");
       eigen_assert(EIGEN_IMPLIES(internal::traits<Derived>::IsAligned, (size_t(m_data) % EIGEN_ALIGN_BYTES) == 0) && "data is not aligned");
     }
 
diff --git a/Eigen/src/Core/util/Macros.h b/Eigen/src/Core/util/Macros.h
index aaa4dcbd4..e9754607b 100644
--- a/Eigen/src/Core/util/Macros.h
+++ b/Eigen/src/Core/util/Macros.h
@@ -592,6 +592,7 @@ namespace Eigen {
   #error Please tell me what is the equivalent of __attribute__((aligned(n))) for your compiler
 #endif
 
+#define EIGEN_ALIGN8  EIGEN_ALIGN_TO_BOUNDARY(8)
 #define EIGEN_ALIGN16 EIGEN_ALIGN_TO_BOUNDARY(16)
 #define EIGEN_ALIGN32 EIGEN_ALIGN_TO_BOUNDARY(32)
 #define EIGEN_ALIGN_DEFAULT EIGEN_ALIGN_TO_BOUNDARY(EIGEN_ALIGN_BYTES)