diff --git a/CMakeLists.txt b/CMakeLists.txt
index 774d46f06..4c375fb97 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -63,15 +63,15 @@ else()
 endif()
 
 # Check OS
-# Use the switch NO_EVENTFD to deactivate eventfd usage indepentent of availability on OS
-if(NOT ${NO_EVENTFD} MATCHES "1")
-    check_include_file("sys/eventfd.h" HAS_EVENTFD)
-else()
-    set(HAS_EVENTFD 0)
-endif()
+check_include_file("sys/eventfd.h" HAS_EVENTFD)
 check_include_file("semaphore.h" HAS_SEMAPHORE)
 check_include_file("sys/mman.h" HAS_MMAN)
 
+# Use the switch NO_EVENTFD to deactivate eventfd usage indepentent of availability on OS
+if(${NO_EVENTFD})
+    set(HAS_EVENTFD OFF)
+endif()
+
 # Check packages
 find_package(PkgConfig REQUIRED)
 find_package(Threads REQUIRED)