diff --git a/CMakeLists.txt b/CMakeLists.txt
index cdabc9660..a87d5b5df 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -466,10 +466,10 @@ if("Ninja" STREQUAL ${CMAKE_GENERATOR})
 endif()
 
 # Add -Werror to C/C++ flags for newer compilers
-#if(NOT CMAKE_CXX_COMPILER_VERSION VERSION_LESS 4.9)
-#  set(CMAKE_C_FLAGS "${CMAKE_C_FLAGS} -Werror")
-#  set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -Werror")
-#endif()
+if(NOT CMAKE_CXX_COMPILER_VERSION VERSION_LESS 4.9)
+  set(CMAKE_C_FLAGS "${CMAKE_C_FLAGS} -Werror")
+  set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -Werror")
+endif()
 
 message(STATUS "CMAKE_C_FLAGS is ${CMAKE_C_FLAGS}")
 message(STATUS "CMAKE_CXX_FLAGS is ${CMAKE_CXX_FLAGS}")