diff --git a/src/system/SYSTEM.h b/src/system/SYSTEM.h
index 130a7f9b..1c0b07fd 100644
--- a/src/system/SYSTEM.h
+++ b/src/system/SYSTEM.h
@@ -32,6 +32,8 @@ typedef unsigned char        SYSTEM_CARD8;
   typedef unsigned int         size_t;
 #endif
 
+#define _SIZE_T_DEFINED_  // For OpenBSD
+
 void *memcpy(void *dest, const void *source, size_t size);
 
 
diff --git a/src/tools/make/configure.c b/src/tools/make/configure.c
index f3ce45fa..6477943b 100644
--- a/src/tools/make/configure.c
+++ b/src/tools/make/configure.c
@@ -16,8 +16,6 @@
 
 #include "SYSTEM.h"
 
-#define _SIZE_T_DEFINED_
-
 
 #ifdef _WIN32
   #define strncasecmp _strnicmp