diff --git a/ap/libc/glibc/glibc-2.23/stdlib/swapcontext.c b/ap/libc/glibc/glibc-2.23/stdlib/swapcontext.c
new file mode 100644
index 0000000..794420a
--- /dev/null
+++ b/ap/libc/glibc/glibc-2.23/stdlib/swapcontext.c
@@ -0,0 +1,29 @@
+/* Copyright (C) 1998-2016 Free Software Foundation, Inc.
+   This file is part of the GNU C Library.
+
+   The GNU 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 2.1 of the License, or (at your option) any later version.
+
+   The GNU 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 GNU C Library; if not, see
+   <http://www.gnu.org/licenses/>.  */
+
+#include <errno.h>
+#include <ucontext.h>
+
+int
+swapcontext (ucontext_t *oucp, const ucontext_t *ucp)
+{
+  __set_errno (ENOSYS);
+  return -1;
+}
+
+
+stub_warning (swapcontext)