Index: uspace/lib/c/include/errno.h
===================================================================
--- uspace/lib/c/include/errno.h	(revision 36082362a46bde6604dea1993953352a0edc3639)
+++ uspace/lib/c/include/errno.h	(revision 4f4b4e7fb8b7c20ca4d80eb4a28ba77472c1274e)
@@ -39,7 +39,7 @@
 #include <fibril.h>
 
-#define errno _errno
+#define errno  (*(__errno()))
 
-extern int _errno;
+extern int *__errno(void) __attribute__((const));
 
 #define EMFILE        (-18)