diff --git a/src/cpulimit.c b/src/cpulimit.c
index 50eabeac..42d7ca28 100644
--- a/src/cpulimit.c
+++ b/src/cpulimit.c
@@ -43,7 +43,7 @@
 #include <sys/types.h>
 #include <sys/wait.h>
 
-#ifdef __APPLE__ || __FREEBSD__
+#if defined(__APPLE__) || defined(__FREEBSD__)
 #include <libgen.h>
 #endif
 
diff --git a/tests/process_iterator_test.c b/tests/process_iterator_test.c
index 16151967..1bfc167b 100644
--- a/tests/process_iterator_test.c
+++ b/tests/process_iterator_test.c
@@ -28,7 +28,7 @@
 #include <signal.h>
 #include <string.h>
 
-#ifdef __APPLE__ || __FREEBSD__
+#if defined(__APPLE__) || defined(__FREEBSD__)
 #include <libgen.h>
 #endif