diff --git a/lib/std/c/darwin.zig b/lib/std/c/darwin.zig
index 3884da6bce..38cddef0fa 100644
--- a/lib/std/c/darwin.zig
+++ b/lib/std/c/darwin.zig
@@ -3894,23 +3894,3 @@ pub const MIN = struct {
 
 pub extern "c" fn mincore(addr: *align(std.mem.page_size) const anyopaque, length: usize, vec: [*]u8) c_int;
 pub extern "c" fn os_proc_available_memory() usize;
-
-pub const thread_affinity_policy = extern struct {
-    tag: integer_t,
-};
-
-pub const thread_policy_flavor_t = natural_t;
-pub const thread_policy_t = [*]integer_t;
-pub const thread_affinity_policy_data_t = thread_affinity_policy;
-pub const thread_affinity_policy_t = [*]thread_affinity_policy;
-
-pub const THREAD_AFFINITY = struct {
-    pub const POLICY = 0;
-    pub const POLICY_COUNT = @as(mach_msg_type_number_t, @intCast(@sizeOf(thread_affinity_policy_data_t) / @sizeOf(integer_t)));
-};
-
-/// cpu affinity api
-/// albeit it is also available on arm64, it always fails as in this architecture there is no sense of
-/// individual cpus (high performance cpus group and low consumption one), thus the pthread QOS api is more appropriate in this case.
-pub extern "c" fn thread_affinity_get(thread: thread_act_t, flavor: thread_policy_flavor_t, info: thread_policy_t, infocnt: [*]mach_msg_type_number_t, default: *boolean_t) kern_return_t;
-pub extern "c" fn thread_affinity_set(thread: thread_act_t, flavor: thread_policy_flavor_t, info: thread_policy_t, infocnt: mach_msg_type_number_t) kern_return_t;