diff --git a/CMakeLists.txt b/CMakeLists.txt
index 6f2332ce0..ba291e450 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -163,7 +163,7 @@ if (CMAKE_COMPILER_IS_GNUCC OR CMAKE_COMPILER_IS_GNUXX)
 endif()
 
 if ("${CMAKE_CXX_COMPILER_ID}" STREQUAL "GNU" OR "${CMAKE_CXX_COMPILER_ID}" MATCHES "Clang")
-    add_compile_options(-Wall)
+    set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -Wall" )
     set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -Wno-reorder" )
 
     # On GCC and Clang, no return from a non-void function is a warning only. Here, we make it an error.