+#ifndef attribute_hidden
+# define attribute_hidden
+#endif
+
+#ifndef __attribute_noinline__
+# if __GNUC__ < 3 || (__GNUC__ == 3 && __GNUC_MINOR__ < 1)
+# define __attribute_noinline__ /* Ignore */
+#else
+# define __attribute_noinline__ __attribute__ ((__noinline__))
+# endif
+#endif
+
+#if ! defined __builtin_expect && __GNUC__ < 3
+# define __builtin_expect(expr, expected) (expr)
+#endif
+
+#ifndef _LIBC
+/* The results of opendir() in this file are not used with dirfd and fchdir,
+ therefore save some unnecessary work in fchdir.c. */
+# undef opendir
+# undef closedir
+
+# if HAVE_ALLOCA
+/* The OS usually guarantees only one guard page at the bottom of the stack,
+ and a page size can be as small as 4096 bytes. So we cannot safely
+ allocate anything larger than 4096 bytes. Also care for the possibility
+ of a few compiler-allocated temporary stack slots. */
+# define __libc_use_alloca(n) ((n) < 4032)
+# else
+/* alloca is implemented with malloc, so just use malloc. */
+# define __libc_use_alloca(n) 0
+# endif
+#endif
+