Index: uspace/lib/libc/include/fibril.h
===================================================================
--- uspace/lib/libc/include/fibril.h	(revision adb49f58f0f19858bac40da225e2394606a6d356)
+++ uspace/lib/libc/include/fibril.h	(revision 450448de4bbf8a458fd2ba9f7c70b64c67a5f4b0)
@@ -76,5 +76,5 @@
 #define fibril_local __thread
 
-extern int context_save(context_t *c);
+extern int context_save(context_t *c) __attribute__ ((returns_twice));
 extern void context_restore(context_t *c) __attribute__ ((noreturn));