+#include <sys/cdefs.h>
+#include <sys/_types.h>
+
+#define __need_mcontext_t
+#define __need_stack_t
+#define __need_ucontext_t
+#include <sys/_structs.h>
+
+#ifndef _SIGSET_T
+#define _SIGSET_T
+typedef __darwin_sigset_t sigset_t;
+#endif
+
+#ifdef KERNEL
+#include <machine/types.h> /* user_addr_t, user_size_t */
+
+/* kernel representation of struct ucontext64 for 64 bit processes */
+typedef struct user_ucontext64 {
+ int uc_onstack;
+ sigset_t uc_sigmask; /* signal mask */
+ struct user64_sigaltstack uc_stack; /* stack */
+ user_addr_t uc_link; /* ucontext pointer */
+ user_size_t uc_mcsize; /* mcontext size */
+ user_addr_t uc_mcontext64; /* machine context */
+} user_ucontext64_t;