+#if defined(LISP_FEATURE_DARWIN)
+#define CONTROL_STACK_ALIGNMENT_BYTES 8192 /* darwin wants page-aligned stacks */
+#define THREAD_ALIGNMENT_BYTES CONTROL_STACK_ALIGNMENT_BYTES
+#else
+#define THREAD_ALIGNMENT_BYTES BACKEND_PAGE_SIZE
+#define CONTROL_STACK_ALIGNMENT_BYTES 16
+#endif
+
+