diff --git a/misc/sys/cdefs.h b/misc/sys/cdefs.h
index 8e244a77cf..b3b5456efd 100644
--- a/misc/sys/cdefs.h
+++ b/misc/sys/cdefs.h
@@ -586,15 +586,23 @@ _Static_assert (0, "IEEE 128-bits long double requires redirection on this platf
 # define __HAVE_GENERIC_SELECTION 0
 #endif
 
-#if __GNUC_PREREQ (10, 0)
 /* Designates a 1-based positional argument ref-index of pointer type
    that can be used to access size-index elements of the pointed-to
    array according to access mode, or at least one element when
    size-index is not provided:
      access (access-mode, <ref-index> [, <size-index>])  */
-#define __attr_access(x) __attribute__ ((__access__ x))
+#if __GNUC_PREREQ (11, 0)
+# define __attr_access(x) __attribute__ ((__access__ x))
+#elif __GNUC_PREREQ (10, 0) && !defined __STRICT_ANSI__
+# define __attr_access(x) __attr_access1 x
+# define __attr_access1(mode, ...) __attr_access##mode (mode, __VA_ARGS__)
+# define __attr_access__none__(mode, ...)
+# define __attr_access__read_only__(mode, ...) \
+    __attribute__ ((__access__ (mode, __VA_ARGS__)))
+# define __attr_access__read_write__ __attr_access__read_only__
+# define __attr_access__write_only__ __attr_access__read_only__
 #else
-#  define __attr_access(x)
+# define __attr_access(x)
 #endif
 
 /* Specify that a function such as setjmp or vfork may return