fix compilation

Eigen/src/Core/util/Memory.h

diff --git a/Eigen/src/Core/util/Memory.h b/Eigen/src/Core/util/Memory.h
index e8af031..f5cdd91 100644
--- a/Eigen/src/Core/util/Memory.h
+++ b/Eigen/src/Core/util/Memory.h
@@ -425,7 +425,7 @@
   * \endcode
   */
 #if (defined __linux__)
-  #define ei_aligned_stack_alloc(SIZE) (SIZE<=EI	GEN_STACK_ALLOCATION_LIMIT) \
+  #define ei_aligned_stack_alloc(SIZE) (SIZE<=EIGEN_STACK_ALLOCATION_LIMIT) \
                                     ? alloca(SIZE) \
                                     : ei_aligned_malloc(SIZE)
   #define ei_aligned_stack_free(PTR,SIZE) if(SIZE>EIGEN_STACK_ALLOCATION_LIMIT) ei_aligned_free(PTR)