diff --git a/libc/include/__/wordsize.h b/libc/include/__/wordsize.h
new file mode 100644
index 00000000..6025b0c5
--- /dev/null
+++ b/libc/include/__/wordsize.h
@@ -0,0 +1,36 @@
+/*******************************************************************************
+
+    Copyright(C) Jonas 'Sortie' Termansen 2011, 2013.
+
+    This file is part of the Sortix C Library.
+
+    The Sortix C Library is free software: you can redistribute it and/or modify
+    it under the terms of the GNU Lesser General Public License as published by
+    the Free Software Foundation, either version 3 of the License, or (at your
+    option) any later version.
+
+    The Sortix C Library is distributed in the hope that it will be useful, but
+    WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
+    or FITNESS FOR A PARTICULAR PURPOSE. See the GNU Lesser General Public
+    License for more details.
+
+    You should have received a copy of the GNU Lesser General Public License
+    along with the Sortix C Library. If not, see <http://www.gnu.org/licenses/>.
+
+    __/wordsize.h
+    Native machine word size.
+
+*******************************************************************************/
+
+#ifndef INCLUDE____WORDSIZE_H
+#define INCLUDE____WORDSIZE_H
+
+#if defined(__x86_64__)
+	#define __WORDSIZE 64
+#elif defined(__i386__)
+	#define __WORDSIZE 32
+#else
+	#error "You need to detect your CPU and declare __WORDSIZE appropriately"
+#endif
+
+#endif