diff --git a/src/solid/mod.rs b/src/solid/mod.rs
index 0182f8150df67..03e4a5c244157 100644
--- a/src/solid/mod.rs
+++ b/src/solid/mod.rs
@@ -219,6 +219,12 @@ pub const LC_MONETARY: c_int = 3;
 pub const LC_NUMERIC: c_int = 4;
 pub const LC_TIME: c_int = 5;
 pub const LC_MESSAGES: c_int = 6;
+#[deprecated(
+    since = "0.2.187",
+    note = "This constant, among others often used in C for the purposes of denoting the latest \
+            value or limit in a set of constants, has been deprecated. See #3131 for details and \
+            discussion."
+)]
 pub const _LC_LAST: c_int = 7;
 
 pub const EPERM: c_int = 1;
diff --git a/src/unix/bsd/netbsdlike/openbsd/mod.rs b/src/unix/bsd/netbsdlike/openbsd/mod.rs
index e642ef18ebc27..bd2c589ab174e 100644
--- a/src/unix/bsd/netbsdlike/openbsd/mod.rs
+++ b/src/unix/bsd/netbsdlike/openbsd/mod.rs
@@ -1736,7 +1736,18 @@ pub const LC_NUMERIC_MASK: c_int = 1 << crate::LC_NUMERIC;
 pub const LC_TIME_MASK: c_int = 1 << crate::LC_TIME;
 pub const LC_MESSAGES_MASK: c_int = 1 << crate::LC_MESSAGES;
 
+#[deprecated(
+    since = "0.2.187",
+    note = "This constant, among others often used in C for the purposes of denoting the latest \
+            value or limit in a set of constants, has been deprecated. See #3131 for details and \
+            discussion."
+)]
 const _LC_LAST: c_int = 7;
+// NOTE: the constant is meant to be marked for deprecation, but its dependent
+// uses are not. This constant is used as a bitmask where all bits for the above
+// `LC_*` constants are on, and so it relies on `_LC_LAST` to more easily
+// accomplish that.
+#[allow(deprecated)]
 pub const LC_ALL_MASK: c_int = (1 << _LC_LAST) - 2;
 
 pub const LC_GLOBAL_LOCALE: crate::locale_t = -1isize as crate::locale_t;
diff --git a/src/unix/linux_like/android/mod.rs b/src/unix/linux_like/android/mod.rs
index c6dd17697adae..77d82cb0222dd 100644
--- a/src/unix/linux_like/android/mod.rs
+++ b/src/unix/linux_like/android/mod.rs
@@ -1937,6 +1937,12 @@ pub const NF_BR_PRI_BRNF: c_int = 0;
 pub const NF_BR_PRI_NAT_DST_OTHER: c_int = 100;
 pub const NF_BR_PRI_FILTER_OTHER: c_int = 200;
 pub const NF_BR_PRI_NAT_SRC: c_int = 300;
+#[deprecated(
+    since = "0.2.187",
+    note = "This constant, among others often used in C for the purposes of denoting the latest \
+            value or limit in a set of constants, has been deprecated. See #3131 for details and \
+            discussion."
+)]
 pub const NF_BR_PRI_LAST: c_int = crate::INT_MAX;
 
 // linux/netfilter_ipv4.h
@@ -1961,6 +1967,12 @@ pub const NF_IP_PRI_NAT_SRC: c_int = 100;
 pub const NF_IP_PRI_SELINUX_LAST: c_int = 225;
 pub const NF_IP_PRI_CONNTRACK_HELPER: c_int = 300;
 pub const NF_IP_PRI_CONNTRACK_CONFIRM: c_int = crate::INT_MAX;
+#[deprecated(
+    since = "0.2.187",
+    note = "This constant, among others often used in C for the purposes of denoting the latest \
+            value or limit in a set of constants, has been deprecated. See #3131 for details and \
+            discussion."
+)]
 pub const NF_IP_PRI_LAST: c_int = crate::INT_MAX;
 
 // linux/netfilter_ipv6.h
@@ -1984,6 +1996,12 @@ pub const NF_IP6_PRI_SECURITY: c_int = 50;
 pub const NF_IP6_PRI_NAT_SRC: c_int = 100;
 pub const NF_IP6_PRI_SELINUX_LAST: c_int = 225;
 pub const NF_IP6_PRI_CONNTRACK_HELPER: c_int = 300;
+#[deprecated(
+    since = "0.2.187",
+    note = "This constant, among others often used in C for the purposes of denoting the latest \
+            value or limit in a set of constants, has been deprecated. See #3131 for details and \
+            discussion."
+)]
 pub const NF_IP6_PRI_LAST: c_int = crate::INT_MAX;
 
 // linux/netfilter_ipv6/ip6_tables.h
diff --git a/src/unix/linux_like/linux/mod.rs b/src/unix/linux_like/linux/mod.rs
index 4c9392ab2434e..48d6db0aac477 100644
--- a/src/unix/linux_like/linux/mod.rs
+++ b/src/unix/linux_like/linux/mod.rs
@@ -2180,6 +2180,12 @@ pub const NF_BR_PRI_BRNF: c_int = 0;
 pub const NF_BR_PRI_NAT_DST_OTHER: c_int = 100;
 pub const NF_BR_PRI_FILTER_OTHER: c_int = 200;
 pub const NF_BR_PRI_NAT_SRC: c_int = 300;
+#[deprecated(
+    since = "0.2.187",
+    note = "This constant, among others often used in C for the purposes of denoting the latest \
+            value or limit in a set of constants, has been deprecated. See #3131 for details and \
+            discussion."
+)]
 pub const NF_BR_PRI_LAST: c_int = crate::INT_MAX;
 
 // linux/netfilter_ipv4.h
@@ -2204,6 +2210,12 @@ pub const NF_IP_PRI_NAT_SRC: c_int = 100;
 pub const NF_IP_PRI_SELINUX_LAST: c_int = 225;
 pub const NF_IP_PRI_CONNTRACK_HELPER: c_int = 300;
 pub const NF_IP_PRI_CONNTRACK_CONFIRM: c_int = crate::INT_MAX;
+#[deprecated(
+    since = "0.2.187",
+    note = "This constant, among others often used in C for the purposes of denoting the latest \
+            value or limit in a set of constants, has been deprecated. See #3131 for details and \
+            discussion."
+)]
 pub const NF_IP_PRI_LAST: c_int = crate::INT_MAX;
 
 // linux/netfilter_ipv6.h
@@ -2227,6 +2239,12 @@ pub const NF_IP6_PRI_SECURITY: c_int = 50;
 pub const NF_IP6_PRI_NAT_SRC: c_int = 100;
 pub const NF_IP6_PRI_SELINUX_LAST: c_int = 225;
 pub const NF_IP6_PRI_CONNTRACK_HELPER: c_int = 300;
+#[deprecated(
+    since = "0.2.187",
+    note = "This constant, among others often used in C for the purposes of denoting the latest \
+            value or limit in a set of constants, has been deprecated. See #3131 for details and \
+            discussion."
+)]
 pub const NF_IP6_PRI_LAST: c_int = crate::INT_MAX;
 
 // linux/netfilter_ipv6/ip6_tables.h
@@ -2304,9 +2322,26 @@ pub const SIOCGIWENCODEEXT: c_ulong = 0x8B35;
 pub const SIOCSIWPMKSA: c_ulong = 0x8B36;
 
 pub const SIOCIWFIRSTPRIV: c_ulong = 0x8BE0;
+#[deprecated(
+    since = "0.2.187",
+    note = "This constant, among others often used in C for the purposes of denoting the latest \
+            value or limit in a set of constants, has been deprecated. See #3131 for details and \
+            discussion."
+)]
 pub const SIOCIWLASTPRIV: c_ulong = 0x8BFF;
 
 pub const SIOCIWFIRST: c_ulong = 0x8B00;
+// NOTE: the symbol we're defining here is itself also deprecated. I can't
+// annotate this with `expect` nor provide a `reason` parameter to the attribute
+// because those were still experimental back in 1.65
+// FIXME(msrv): change this to an `expect` with a `reason` once we bump.
+#[allow(deprecated)]
+#[deprecated(
+    since = "0.2.187",
+    note = "This constant, among others often used in C for the purposes of denoting the latest \
+            value or limit in a set of constants, has been deprecated. See #3131 for details and \
+            discussion."
+)]
 pub const SIOCIWLAST: c_ulong = SIOCIWLASTPRIV;
 
 pub const IWEVTXDROP: c_ulong = 0x8C00;
diff --git a/src/unix/solarish/illumos.rs b/src/unix/solarish/illumos.rs
index b31c31bd1f6c8..8f5b84a34390e 100644
--- a/src/unix/solarish/illumos.rs
+++ b/src/unix/solarish/illumos.rs
@@ -152,6 +152,12 @@ pub const LOCK_EX: c_int = 2;
 pub const LOCK_NB: c_int = 4;
 pub const LOCK_UN: c_int = 8;
 
+#[deprecated(
+    since = "0.2.187",
+    note = "This constant, among others often used in C for the purposes of denoting the latest \
+            value or limit in a set of constants, has been deprecated. See #3131 for details and \
+            discussion."
+)]
 pub const _PC_LAST: c_int = 101;
 
 pub const _CS_PATH: c_int = 65;
diff --git a/src/unix/solarish/solaris.rs b/src/unix/solarish/solaris.rs
index 992df9ddc0ad9..2d20309970dbc 100644
--- a/src/unix/solarish/solaris.rs
+++ b/src/unix/solarish/solaris.rs
@@ -132,6 +132,12 @@ pub const F_DUPFD_CLOFORK: c_int = 49;
 pub const F_DUP2FD_CLOEXEC: c_int = 48;
 pub const F_DUP2FD_CLOFORK: c_int = 50;
 
+#[deprecated(
+    since = "0.2.187",
+    note = "This constant, among others often used in C for the purposes of denoting the latest \
+            value or limit in a set of constants, has been deprecated. See #3131 for details and \
+            discussion."
+)]
 pub const _PC_LAST: c_int = 102;
 
 pub const PRIV_PROC_SENSITIVE: c_uint = 0x0008;