diff --git a/CMakeLists.txt b/CMakeLists.txt
index 89b5775a18..1cc5b48a8d 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -514,7 +514,7 @@ if(ENABLE_MASON)
   set(CMAKE_MODULE_LINKER_FLAGS "${CMAKE_MODULE_LINKER_FLAGS} ${LINKER_FLAGS}")
 
   # current mason packages target -D_GLIBCXX_USE_CXX11_ABI=0
-  set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -D_GLIBCXX_USE_CXX11_ABI=0")
+  add_dependency_defines(-D_GLIBCXX_USE_CXX11_ABI=0)
 
   # note: we avoid calling find_package(Osmium ...) here to ensure that the
   # expat and bzip2 are used from mason rather than the system