diff --git a/Eigen/src/Core/util/Memory.h b/Eigen/src/Core/util/Memory.h
index 7657ead80..9823fa30f 100644
--- a/Eigen/src/Core/util/Memory.h
+++ b/Eigen/src/Core/util/Memory.h
@@ -216,6 +216,7 @@ EIGEN_DEVICE_FUNC inline void aligned_free(void *ptr)
   */
 inline void* aligned_realloc(void *ptr, std::size_t new_size, std::size_t old_size)
 {
+  if (ptr == 0) return aligned_malloc(new_size);
   EIGEN_UNUSED_VARIABLE(old_size)
 
   void *result;