diff --git a/CMakeLists.txt b/CMakeLists.txt
index 8aa0529792..0e2dcecb3b 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -404,8 +404,7 @@ if ("${CMAKE_CXX_COMPILER_ID}" STREQUAL "Clang")
  	SET(CMAKE_C_FLAGS "${CMAKE_C_FLAGS} -std=c99")
 
 	# Use modern C++11
-	# --> Seems to break Eigen (??)
- 	#SET(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -std=c++11")
+ 	SET(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -std=c++11")
 
 	IF(NOT APPLE) # any reason for not using it in all platforms?
 	# Use the libstdc++ lib vs. libc++, to avoid some build errors in MacOS