diff --git a/hwaccess.c b/hwaccess.c
index 3a9ca57..aa35f4b 100644
--- a/hwaccess.c
+++ b/hwaccess.c
@@ -30,11 +30,11 @@
 #include "programmer.h"
 #include "hwaccess.h"
 
-#if !(IS_LINUX || IS_MACOSX || defined(__NetBSD__) || defined(__OpenBSD__) || defined(__FreeBSD__) || defined(__FreeBSD_kernel__) || defined(__DragonFly__) || defined(__DJGPP__) || defined(__LIBPAYLOAD__) || defined(__sun) || defined(__gnu_hurd__))
+#if !(defined(__gnu_linux__) || defined(__linux__) || defined(__APPLE__) && defined(__MACH__) || defined(__NetBSD__) || defined(__OpenBSD__) || defined(__FreeBSD__) || defined(__FreeBSD_kernel__) || defined(__DragonFly__) || defined(__DJGPP__) || defined(__LIBPAYLOAD__) || defined(__sun) || defined(__gnu_hurd__))
 #error "Unknown operating system"
 #endif
 
-#if IS_LINUX || IS_MACOSX || defined(__NetBSD__) || defined(__OpenBSD__)
+#if defined(__gnu_linux__) || defined(__linux__) || defined(__APPLE__) && defined(__MACH__) || defined(__NetBSD__) || defined(__OpenBSD__)
 #define USE_IOPL 1
 #else
 #define USE_IOPL 0
diff --git a/platform.h b/platform.h
index 9bbde54..34a56ab 100644
--- a/platform.h
+++ b/platform.h
@@ -21,16 +21,6 @@
 #define __PLATFORM_H__ 1
 
 // Helper defines for operating systems
-#if defined(__gnu_linux__) || defined(__linux__)
-#define IS_LINUX 1
-#else
-#define IS_LINUX 0
-#endif
-#if defined(__APPLE__) && defined(__MACH__) /* yes, both. */
-#define IS_MACOSX 1
-#else
-#define IS_MACOSX 0
-#endif
 #if defined(_WIN32) || defined(_WIN64) || defined(__WIN32__) || defined(__WINDOWS__)
 #define IS_WINDOWS 1
 #else