diff --git a/src/fuchsia/mod.rs b/src/fuchsia/mod.rs
index e8c8719f9cbac..bf1a543609406 100644
--- a/src/fuchsia/mod.rs
+++ b/src/fuchsia/mod.rs
@@ -2811,7 +2811,10 @@ pub const POSIX_MADV_DONTNEED: ::c_int = 4;
 
 pub const RLIM_INFINITY: ::rlim_t = !0;
 pub const RLIMIT_RTTIME: ::c_int = 15;
+#[deprecated(since = "0.2.64", note = "Not stable across OS versions")]
 pub const RLIMIT_NLIMITS: ::c_int = 16;
+#[allow(deprecated)]
+#[deprecated(since = "0.2.64", note = "Not stable across OS versions")]
 pub const RLIM_NLIMITS: ::c_int = RLIMIT_NLIMITS;
 
 pub const MAP_ANONYMOUS: ::c_int = MAP_ANON;
diff --git a/src/unix/aix/mod.rs b/src/unix/aix/mod.rs
index bc02b108dc412..66e4b7cf67204 100644
--- a/src/unix/aix/mod.rs
+++ b/src/unix/aix/mod.rs
@@ -1762,6 +1762,7 @@ pub const PRIO_USER: ::c_int = 2;
 pub const RUSAGE_THREAD: ::c_int = 1;
 pub const RLIM_SAVED_MAX: ::c_ulong = RLIM_INFINITY - 1;
 pub const RLIM_SAVED_CUR: ::c_ulong = RLIM_INFINITY - 2;
+#[deprecated(since = "0.2.64", note = "Not stable across OS versions")]
 pub const RLIM_NLIMITS: ::c_int = 10;
 
 // sys/sched.h
diff --git a/src/unix/haiku/mod.rs b/src/unix/haiku/mod.rs
index 8bfb78b786753..00e9523c9865a 100644
--- a/src/unix/haiku/mod.rs
+++ b/src/unix/haiku/mod.rs
@@ -741,6 +741,7 @@ pub const RLIMIT_AS: ::c_int = 6;
 pub const RLIM_INFINITY: ::rlim_t = 0xffffffff;
 // Haiku specific
 pub const RLIMIT_NOVMON: ::c_int = 7;
+#[deprecated(since = "0.2.64", note = "Not stable across OS versions")]
 pub const RLIM_NLIMITS: ::c_int = 8;
 
 pub const RUSAGE_SELF: ::c_int = 0;
diff --git a/src/unix/linux_like/android/mod.rs b/src/unix/linux_like/android/mod.rs
index cdac6c32ee3f4..b2ef7973806dd 100644
--- a/src/unix/linux_like/android/mod.rs
+++ b/src/unix/linux_like/android/mod.rs
@@ -1562,6 +1562,7 @@ pub const RLIMIT_MSGQUEUE: ::c_int = 12;
 pub const RLIMIT_NICE: ::c_int = 13;
 pub const RLIMIT_RTPRIO: ::c_int = 14;
 
+#[deprecated(since = "0.2.64", note = "Not stable across OS versions")]
 pub const RLIM_NLIMITS: ::c_int = 16;
 pub const RLIM_INFINITY: ::rlim_t = !0;
 
diff --git a/src/unix/linux_like/emscripten/mod.rs b/src/unix/linux_like/emscripten/mod.rs
index 0457f5dadea70..1c9e4e6f5b178 100644
--- a/src/unix/linux_like/emscripten/mod.rs
+++ b/src/unix/linux_like/emscripten/mod.rs
@@ -1230,7 +1230,10 @@ pub const POSIX_FADV_NOREUSE: ::c_int = 5;
 pub const POSIX_MADV_DONTNEED: ::c_int = 0;
 
 pub const RLIM_INFINITY: ::rlim_t = !0;
+#[deprecated(since = "0.2.64", note = "Not stable across OS versions")]
 pub const RLIMIT_NLIMITS: ::c_int = 15;
+#[allow(deprecated)]
+#[deprecated(since = "0.2.64", note = "Not stable across OS versions")]
 pub const RLIM_NLIMITS: ::c_int = RLIMIT_NLIMITS;
 
 pub const MAP_ANONYMOUS: ::c_int = MAP_ANON;
diff --git a/src/unix/linux_like/linux/arch/generic/mod.rs b/src/unix/linux_like/linux/arch/generic/mod.rs
index 19d5e7b3938c1..10e1fcca630dd 100644
--- a/src/unix/linux_like/linux/arch/generic/mod.rs
+++ b/src/unix/linux_like/linux/arch/generic/mod.rs
@@ -257,6 +257,8 @@ cfg_if! {
         pub const RLIMIT_NICE: ::__rlimit_resource_t = 13;
         pub const RLIMIT_RTPRIO: ::__rlimit_resource_t = 14;
         pub const RLIMIT_RTTIME: ::__rlimit_resource_t = 15;
+        #[allow(deprecated)]
+        #[deprecated(since = "0.2.64", note = "Not stable across OS versions")]
         pub const RLIMIT_NLIMITS: ::__rlimit_resource_t = RLIM_NLIMITS;
 
     } else if #[cfg(any(target_env = "musl", target_env = "ohos"))] {
@@ -277,16 +279,21 @@ cfg_if! {
         pub const RLIMIT_NICE: ::c_int = 13;
         pub const RLIMIT_RTPRIO: ::c_int = 14;
         pub const RLIMIT_RTTIME: ::c_int = 15;
+        #[deprecated(since = "0.2.64", note = "Not stable across OS versions")]
         pub const RLIM_NLIMITS: ::c_int = 15;
+        #[allow(deprecated)]
+        #[deprecated(since = "0.2.64", note = "Not stable across OS versions")]
         pub const RLIMIT_NLIMITS: ::c_int = RLIM_NLIMITS;
     }
 }
 
 cfg_if! {
     if #[cfg(target_env = "gnu")] {
+        #[deprecated(since = "0.2.64", note = "Not stable across OS versions")]
         pub const RLIM_NLIMITS: ::__rlimit_resource_t = 16;
     }
     else if #[cfg(target_env = "uclibc")] {
+        #[deprecated(since = "0.2.64", note = "Not stable across OS versions")]
         pub const RLIM_NLIMITS: ::__rlimit_resource_t = 15;
     }
 }
diff --git a/src/unix/linux_like/linux/arch/mips/mod.rs b/src/unix/linux_like/linux/arch/mips/mod.rs
index 975e334de5ffb..6c0aecf8cbac3 100644
--- a/src/unix/linux_like/linux/arch/mips/mod.rs
+++ b/src/unix/linux_like/linux/arch/mips/mod.rs
@@ -237,6 +237,8 @@ cfg_if! {
         pub const RLIMIT_NICE: ::__rlimit_resource_t = 13;
         pub const RLIMIT_RTPRIO: ::__rlimit_resource_t = 14;
         pub const RLIMIT_RTTIME: ::__rlimit_resource_t = 15;
+        #[allow(deprecated)]
+        #[deprecated(since = "0.2.64", note = "Not stable across OS versions")]
         pub const RLIMIT_NLIMITS: ::__rlimit_resource_t = RLIM_NLIMITS;
 
     } else if #[cfg(target_env = "musl")] {
@@ -257,7 +259,10 @@ cfg_if! {
         pub const RLIMIT_NICE: ::c_int = 13;
         pub const RLIMIT_RTPRIO: ::c_int = 14;
         pub const RLIMIT_RTTIME: ::c_int = 15;
+        #[deprecated(since = "0.2.64", note = "Not stable across OS versions")]
         pub const RLIM_NLIMITS: ::c_int = 15;
+        #[allow(deprecated)]
+        #[deprecated(since = "0.2.64", note = "Not stable across OS versions")]
         pub const RLIMIT_NLIMITS: ::c_int = RLIM_NLIMITS;
         pub const RLIM_INFINITY: ::rlim_t = !0;
     }
@@ -265,8 +270,10 @@ cfg_if! {
 
 cfg_if! {
     if #[cfg(target_env = "gnu")] {
+        #[deprecated(since = "0.2.64", note = "Not stable across OS versions")]
         pub const RLIM_NLIMITS: ::__rlimit_resource_t = 16;
     } else if #[cfg(target_env = "uclibc")] {
+        #[deprecated(since = "0.2.64", note = "Not stable across OS versions")]
         pub const RLIM_NLIMITS: ::__rlimit_resource_t = 15;
     }
 }
diff --git a/src/unix/linux_like/linux/arch/powerpc/mod.rs b/src/unix/linux_like/linux/arch/powerpc/mod.rs
index 64c3eaab543a6..584be5b6c2860 100644
--- a/src/unix/linux_like/linux/arch/powerpc/mod.rs
+++ b/src/unix/linux_like/linux/arch/powerpc/mod.rs
@@ -215,7 +215,10 @@ cfg_if! {
         pub const RLIMIT_NICE: ::__rlimit_resource_t = 13;
         pub const RLIMIT_RTPRIO: ::__rlimit_resource_t = 14;
         pub const RLIMIT_RTTIME: ::__rlimit_resource_t = 15;
+        #[deprecated(since = "0.2.64", note = "Not stable across OS versions")]
         pub const RLIM_NLIMITS: ::__rlimit_resource_t = 16;
+        #[allow(deprecated)]
+        #[deprecated(since = "0.2.64", note = "Not stable across OS versions")]
         pub const RLIMIT_NLIMITS: ::__rlimit_resource_t = RLIM_NLIMITS;
 
     } else if #[cfg(target_env = "musl")] {
@@ -236,7 +239,10 @@ cfg_if! {
         pub const RLIMIT_NICE: ::c_int = 13;
         pub const RLIMIT_RTPRIO: ::c_int = 14;
         pub const RLIMIT_RTTIME: ::c_int = 15;
+        #[deprecated(since = "0.2.64", note = "Not stable across OS versions")]
         pub const RLIM_NLIMITS: ::c_int = 15;
+        #[allow(deprecated)]
+        #[deprecated(since = "0.2.64", note = "Not stable across OS versions")]
         pub const RLIMIT_NLIMITS: ::c_int = RLIM_NLIMITS;
     }
 }
diff --git a/src/unix/linux_like/linux/arch/sparc/mod.rs b/src/unix/linux_like/linux/arch/sparc/mod.rs
index da3e388e3d286..c7813aa46be61 100644
--- a/src/unix/linux_like/linux/arch/sparc/mod.rs
+++ b/src/unix/linux_like/linux/arch/sparc/mod.rs
@@ -216,7 +216,10 @@ pub const RLIMIT_MSGQUEUE: ::__rlimit_resource_t = 12;
 pub const RLIMIT_NICE: ::__rlimit_resource_t = 13;
 pub const RLIMIT_RTPRIO: ::__rlimit_resource_t = 14;
 pub const RLIMIT_RTTIME: ::__rlimit_resource_t = 15;
+#[deprecated(since = "0.2.64", note = "Not stable across OS versions")]
 pub const RLIM_NLIMITS: ::__rlimit_resource_t = 16;
+#[allow(deprecated)]
+#[deprecated(since = "0.2.64", note = "Not stable across OS versions")]
 pub const RLIMIT_NLIMITS: ::__rlimit_resource_t = RLIM_NLIMITS;
 
 cfg_if! {
diff --git a/src/unix/linux_like/linux/musl/b32/hexagon.rs b/src/unix/linux_like/linux/musl/b32/hexagon.rs
index f83d208d5fe8f..49e000ce97f1e 100644
--- a/src/unix/linux_like/linux/musl/b32/hexagon.rs
+++ b/src/unix/linux_like/linux/musl/b32/hexagon.rs
@@ -265,7 +265,6 @@ pub const PF_FILE: ::c_int = 1;
 pub const PF_KCM: ::c_int = 41;
 pub const PF_MAX: ::c_int = 43;
 pub const PF_QIPCRTR: ::c_int = 42;
-#[deprecated(since = "0.2.64", note = "Not stable across OS versions")]
 pub const SA_ONSTACK: ::c_int = 0x08000000;
 pub const SA_SIGINFO: ::c_int = 0x00000004;
 pub const SA_NOCLDWAIT: ::c_int = 0x00000002;
diff --git a/src/unix/nto/mod.rs b/src/unix/nto/mod.rs
index ed6f6df41368e..91e531ffd7961 100644
--- a/src/unix/nto/mod.rs
+++ b/src/unix/nto/mod.rs
@@ -2557,6 +2557,7 @@ pub const RLIMIT_NPROC: ::c_int = 8;
 pub const RLIMIT_RSS: ::c_int = 6;
 pub const RLIMIT_STACK: ::c_int = 3;
 pub const RLIMIT_VMEM: ::c_int = 6;
+#[deprecated(since = "0.2.64", note = "Not stable across OS versions")]
 pub const RLIM_NLIMITS: ::c_int = 14;
 
 pub const SCHED_ADJTOHEAD: ::c_int = 5;