+
+extern void
+protect_control_stack_hard_guard_page(int protect_p, struct thread *thread);
+extern void
+protect_control_stack_guard_page(int protect_p, struct thread *thread);
+extern void
+protect_control_stack_return_guard_page(int protect_p, struct thread *thread);
+extern void
+protect_binding_stack_hard_guard_page(int protect_p, struct thread *thread);
+extern void
+protect_binding_stack_guard_page(int protect_p, struct thread *thread);
+extern void
+protect_binding_stack_return_guard_page(int protect_p, struct thread *thread);
+extern void
+protect_alien_stack_hard_guard_page(int protect_p, struct thread *thread);
+extern void
+protect_alien_stack_guard_page(int protect_p, struct thread *thread);
+extern void
+protect_alien_stack_return_guard_page(int protect_p, struct thread *thread);
+extern os_vm_address_t undefined_alien_address;