diff --git a/libc-test/test/linux_elf.rs b/libc-test/test/linux_elf.rs
index 8744200e82aa592031e97aefe66caeb3fcfacfaa..d149c9aaff38e043bc437120cf5263f4983e19ec 100644
--- a/libc-test/test/linux_elf.rs
+++ b/libc-test/test/linux_elf.rs
@@ -7,4 +7,6 @@ use libc::*;
 include!(concat!(env!("OUT_DIR"), "/linux_elf.rs"));
 
 #[cfg(not(target_os = "linux"))]
-fn main() { println!("PASSED 0 tests"); }
+fn main() {
+    println!("PASSED 0 tests");
+}
diff --git a/libc-test/test/linux_fcntl.rs b/libc-test/test/linux_fcntl.rs
index 915a87dc7595b2fec5718427fef341345301e38f..49c06cc4f6517a114e11e12756d0bfa0fbab2990 100644
--- a/libc-test/test/linux_fcntl.rs
+++ b/libc-test/test/linux_fcntl.rs
@@ -7,4 +7,6 @@ use libc::*;
 include!(concat!(env!("OUT_DIR"), "/linux_fcntl.rs"));
 
 #[cfg(not(any(target_os = "linux", target_os = "android")))]
-fn main() { println!("PASSED 0 tests"); }
+fn main() {
+    println!("PASSED 0 tests");
+}
diff --git a/libc-test/test/linux_ipv6.rs b/libc-test/test/linux_ipv6.rs
index c4d0965a0f99090818a1b895447b8db215effa76..83c389ce16a0345fbc2204871c390115bcb312c9 100644
--- a/libc-test/test/linux_ipv6.rs
+++ b/libc-test/test/linux_ipv6.rs
@@ -7,4 +7,6 @@ use libc::*;
 include!(concat!(env!("OUT_DIR"), "/linux_ipv6.rs"));
 
 #[cfg(not(target_os = "linux"))]
-fn main() { println!("PASSED 0 tests"); }
+fn main() {
+    println!("PASSED 0 tests");
+}
diff --git a/libc-test/test/linux_strerror_r.rs b/libc-test/test/linux_strerror_r.rs
index 5139175f9ead6aa6b7e75ac407341402ccf9fcf1..17db959d8cb933edc21f6165bc1c5be225ac1174 100644
--- a/libc-test/test/linux_strerror_r.rs
+++ b/libc-test/test/linux_strerror_r.rs
@@ -7,4 +7,6 @@ use libc::*;
 include!(concat!(env!("OUT_DIR"), "/linux_strerror_r.rs"));
 
 #[cfg(not(any(target_os = "linux", target_os = "android")))]
-fn main() { println!("PASSED 0 tests"); }
+fn main() {
+    println!("PASSED 0 tests");
+}
diff --git a/libc-test/test/linux_termios.rs b/libc-test/test/linux_termios.rs
index 9ee47631e530b4d2631195e7e243d2d6b9b41edd..703a9b9b25b0d721ab76c201256dacc8802c1911 100644
--- a/libc-test/test/linux_termios.rs
+++ b/libc-test/test/linux_termios.rs
@@ -7,4 +7,6 @@ use libc::*;
 include!(concat!(env!("OUT_DIR"), "/linux_termios.rs"));
 
 #[cfg(not(any(target_os = "linux", target_os = "android")))]
-fn main() { println!("PASSED 0 tests"); }
+fn main() {
+    println!("PASSED 0 tests");
+}
diff --git a/src/fuchsia/aarch64.rs b/src/fuchsia/aarch64.rs
index 572f8c1ce3ae10173d9110d01c979785c9ebacb4..654e8d1b2558915764c4f0259885135c31671f17 100644
--- a/src/fuchsia/aarch64.rs
+++ b/src/fuchsia/aarch64.rs
@@ -66,8 +66,19 @@ pub const MINSIGSTKSZ: ::size_t = 6144;
 pub const SIGSTKSZ: ::size_t = 12288;
 
 #[doc(hidden)]
+#[deprecated(
+    since = "0.2.55",
+    note = "If you are using this report to: \
+            https://github.com/rust-lang/libc/issues/665"
+)]
 pub const PF_MAX: ::c_int = 43;
 #[doc(hidden)]
+#[deprecated(
+    since = "0.2.55",
+    note = "If you are using this report to: \
+            https://github.com/rust-lang/libc/issues/665"
+)]
+#[allow(deprecated)]
 pub const AF_MAX: ::c_int = PF_MAX;
 
 pub const SYS_io_setup: ::c_long = 0;
diff --git a/src/fuchsia/x86_64.rs b/src/fuchsia/x86_64.rs
index eb220998e870a5b1637c9a339a738b53054d8c87..e01f16d425a04756e3cb3380dd019da63ce6ff5c 100644
--- a/src/fuchsia/x86_64.rs
+++ b/src/fuchsia/x86_64.rs
@@ -486,6 +486,17 @@ pub const SIGSTKSZ: ::size_t = 8192;
 pub const MINSIGSTKSZ: ::size_t = 2048;
 
 #[doc(hidden)]
+#[deprecated(
+    since = "0.2.55",
+    note = "If you are using this report to: \
+            https://github.com/rust-lang/libc/issues/665"
+)]
 pub const AF_MAX: ::c_int = 42;
 #[doc(hidden)]
+#[deprecated(
+    since = "0.2.55",
+    note = "If you are using this report to: \
+            https://github.com/rust-lang/libc/issues/665"
+)]
+#[allow(deprecated)]
 pub const PF_MAX: ::c_int = AF_MAX;
diff --git a/src/unix/bsd/apple/mod.rs b/src/unix/bsd/apple/mod.rs
index f4343dee5b8cf84a262a4998db3231929db7ee44..0c838a711590471e29dbe06db46ccf00799eb53d 100644
--- a/src/unix/bsd/apple/mod.rs
+++ b/src/unix/bsd/apple/mod.rs
@@ -2083,6 +2083,11 @@ pub const AF_NETBIOS: ::c_int = 33;
 pub const AF_PPP: ::c_int = 34;
 pub const pseudo_AF_HDRCMPLT: ::c_int = 35;
 #[doc(hidden)]
+#[deprecated(
+    since = "0.2.55",
+    note = "If you are using this report to: \
+            https://github.com/rust-lang/libc/issues/665"
+)]
 pub const AF_MAX: ::c_int = 40;
 pub const AF_SYS_CONTROL: ::c_int = 2;
 
@@ -2125,11 +2130,21 @@ pub const PF_SYSTEM: ::c_int = AF_SYSTEM;
 pub const PF_NETBIOS: ::c_int = AF_NETBIOS;
 pub const PF_PPP: ::c_int =  AF_PPP;
 #[doc(hidden)]
-#[deprecated(since = "0.2.55")]
+#[deprecated(
+    since = "0.2.55",
+    note = "If you are using this report to: \
+            https://github.com/rust-lang/libc/issues/665"
+)]
+#[allow(deprecated)]
 pub const PF_MAX: ::c_int =  AF_MAX;
 
 #[doc(hidden)]
-#[deprecated(since = "0.2.55")]
+#[deprecated(
+    since = "0.2.55",
+    note = "If you are using this report to: \
+            https://github.com/rust-lang/libc/issues/665"
+)]
+#[allow(deprecated)]
 pub const NET_MAXID: ::c_int = AF_MAX;
 
 pub const NET_RT_DUMP: ::c_int = 1;
diff --git a/src/unix/bsd/freebsdlike/dragonfly/mod.rs b/src/unix/bsd/freebsdlike/dragonfly/mod.rs
index b0604a2b19d4246bdd6f787495f5c0aeac7f9fce..0c6de20189f998bd8c13cb63bfa62d9a33cf979c 100644
--- a/src/unix/bsd/freebsdlike/dragonfly/mod.rs
+++ b/src/unix/bsd/freebsdlike/dragonfly/mod.rs
@@ -891,9 +891,22 @@ pub const TCP_FASTKEEP:   ::c_int = 128;
 pub const AF_BLUETOOTH: ::c_int = 33;
 pub const AF_MPLS: ::c_int = 34;
 pub const AF_IEEE80211: ::c_int = 35;
+#[doc(hidden)]
+#[deprecated(
+    since = "0.2.55",
+    note = "If you are using this report to: \
+            https://github.com/rust-lang/libc/issues/665"
+)]
 pub const AF_MAX: ::c_int = 36;
 
 pub const PF_BLUETOOTH: ::c_int = AF_BLUETOOTH;
+#[doc(hidden)]
+#[deprecated(
+    since = "0.2.55",
+    note = "If you are using this report to: \
+            https://github.com/rust-lang/libc/issues/665"
+)]
+#[allow(deprecated)]
 pub const PF_MAX: ::c_int = AF_MAX;
 
 pub const NET_RT_DUMP: ::c_int = 1;
@@ -904,6 +917,12 @@ pub const NET_RT_MAXID: ::c_int = 4;
 pub const SOMAXOPT_SIZE: ::c_int = 65536;
 
 #[doc(hidden)]
+#[deprecated(
+    since = "0.2.55",
+    note = "If you are using this report to: \
+            https://github.com/rust-lang/libc/issues/665"
+)]
+#[allow(deprecated)]
 pub const NET_MAXID: ::c_int = AF_MAX;
 
 pub const MSG_UNUSED09: ::c_int = 0x00000200;
diff --git a/src/unix/bsd/freebsdlike/freebsd/mod.rs b/src/unix/bsd/freebsdlike/freebsd/mod.rs
index d7d4c6c62616e41bb4400b7a82bd669331d86081..f5085f5f58d9a937d0f4970fe03f0bc08a92817f 100644
--- a/src/unix/bsd/freebsdlike/freebsd/mod.rs
+++ b/src/unix/bsd/freebsdlike/freebsd/mod.rs
@@ -625,6 +625,11 @@ pub const AF_IEEE80211: ::c_int = 37;
 pub const AF_INET_SDP: ::c_int = 40;
 pub const AF_INET6_SDP: ::c_int = 42;
 #[doc(hidden)]
+#[deprecated(
+    since = "0.2.55",
+    note = "If you are using this report to: \
+            https://github.com/rust-lang/libc/issues/665"
+)]
 pub const AF_MAX: ::c_int = 42;
 
 // https://github.com/freebsd/freebsd/blob/master/sys/net/if.h#L140
@@ -636,7 +641,6 @@ pub const IFF_POINTOPOINT: ::c_int = 0x10; // (i) is a point-to-point link
 // 0x20           was IFF_SMART
 pub const IFF_RUNNING: ::c_int = 0x40; // (d) resources allocated
 #[doc(hidden)]
-#[doc(hidden)]
 #[deprecated(
     since="0.2.54",
     note="IFF_DRV_RUNNING is deprecated. Use the portable IFF_RUNNING instead"
@@ -934,6 +938,12 @@ pub const PF_IEEE80211: ::c_int = AF_IEEE80211;
 pub const PF_INET_SDP: ::c_int = AF_INET_SDP;
 pub const PF_INET6_SDP: ::c_int = AF_INET6_SDP;
 #[doc(hidden)]
+#[deprecated(
+    since = "0.2.55",
+    note = "If you are using this report to: \
+            https://github.com/rust-lang/libc/issues/665"
+)]
+#[allow(deprecated)]
 pub const PF_MAX: ::c_int = AF_MAX;
 
 pub const NET_RT_DUMP: ::c_int = 1;
@@ -971,6 +981,7 @@ pub const SHM_ANON: *mut ::c_char = 1 as *mut ::c_char;
 // compatibility only, and are scheduled to be removed in libc 1.0.0.
 #[doc(hidden)]
 #[deprecated(since="0.2.54",note="Removed in FreeBSD 11")]
+#[allow(deprecated)]
 pub const NET_MAXID: ::c_int = AF_MAX;
 #[doc(hidden)]
 #[deprecated(since="0.2.54",note="Removed in FreeBSD 11")]
diff --git a/src/unix/bsd/netbsdlike/netbsd/mod.rs b/src/unix/bsd/netbsdlike/netbsd/mod.rs
index d4ccd6775a5bd9bc77f88344467d2e85cbe3de3b..5f78790dea3003f8684e629268e3165a0edc23d7 100644
--- a/src/unix/bsd/netbsdlike/netbsd/mod.rs
+++ b/src/unix/bsd/netbsdlike/netbsd/mod.rs
@@ -853,8 +853,21 @@ pub const AF_BLUETOOTH: ::c_int = 31;
 pub const AF_IEEE80211: ::c_int = 32;
 pub const AF_MPLS: ::c_int = 33;
 pub const AF_ROUTE: ::c_int = 34;
+#[doc(hidden)]
+#[deprecated(
+    since = "0.2.55",
+    note = "If you are using this report to: \
+            https://github.com/rust-lang/libc/issues/665"
+)]
 pub const AF_MAX: ::c_int = 36;
 
+#[doc(hidden)]
+#[deprecated(
+    since = "0.2.55",
+    note = "If you are using this report to: \
+            https://github.com/rust-lang/libc/issues/665"
+)]
+#[allow(deprecated)]
 pub const NET_MAXID: ::c_int = AF_MAX;
 pub const NET_RT_DUMP: ::c_int = 1;
 pub const NET_RT_FLAGS: ::c_int = 2;
@@ -870,6 +883,14 @@ pub const PF_KEY: ::c_int = pseudo_AF_KEY;
 pub const PF_BLUETOOTH: ::c_int = AF_BLUETOOTH;
 pub const PF_MPLS: ::c_int = AF_MPLS;
 pub const PF_ROUTE: ::c_int = AF_ROUTE;
+
+#[doc(hidden)]
+#[deprecated(
+    since = "0.2.55",
+    note = "If you are using this report to: \
+            https://github.com/rust-lang/libc/issues/665"
+)]
+#[allow(deprecated)]
 pub const PF_MAX: ::c_int = AF_MAX;
 
 pub const MSG_NBIO: ::c_int = 0x1000;
diff --git a/src/unix/bsd/netbsdlike/openbsd/mod.rs b/src/unix/bsd/netbsdlike/openbsd/mod.rs
index e3efae9e8bf58b81be7ad8e0aa14f14a2cd808e2..ba3b2d1bb4dcbb1455d415a4666e39c5ad99e3a5 100644
--- a/src/unix/bsd/netbsdlike/openbsd/mod.rs
+++ b/src/unix/bsd/netbsdlike/openbsd/mod.rs
@@ -835,9 +835,20 @@ pub const AF_MPLS: ::c_int = 33;
 pub const pseudo_AF_PFLOW: ::c_int = 34;
 pub const pseudo_AF_PIPEX: ::c_int = 35;
 #[doc(hidden)]
+#[deprecated(
+    since = "0.2.55",
+    note = "If you are using this report to: \
+            https://github.com/rust-lang/libc/issues/665"
+)]
 pub const AF_MAX: ::c_int = 36;
 
 #[doc(hidden)]
+#[allow(deprecated)]
+#[deprecated(
+    since = "0.2.55",
+    note = "If you are using this report to: \
+            https://github.com/rust-lang/libc/issues/665"
+)]
 pub const NET_MAXID: ::c_int = AF_MAX;
 pub const NET_RT_DUMP: ::c_int = 1;
 pub const NET_RT_FLAGS: ::c_int = 2;
@@ -862,6 +873,12 @@ pub const PF_MPLS: ::c_int = AF_MPLS;
 pub const PF_PFLOW: ::c_int = pseudo_AF_PFLOW;
 pub const PF_PIPEX: ::c_int = pseudo_AF_PIPEX;
 #[doc(hidden)]
+#[allow(deprecated)]
+#[deprecated(
+    since = "0.2.55",
+    note = "If you are using this report to: \
+            https://github.com/rust-lang/libc/issues/665"
+)]
 pub const PF_MAX: ::c_int = AF_MAX;
 
 pub const SCM_TIMESTAMP: ::c_int = 0x04;
diff --git a/src/unix/haiku/mod.rs b/src/unix/haiku/mod.rs
index 56df0db586dc85917929b209a30db62b429d4363..be9a6cf3ccb5e3ade4ce6fa503bf686cac8b9ecd 100644
--- a/src/unix/haiku/mod.rs
+++ b/src/unix/haiku/mod.rs
@@ -770,6 +770,12 @@ pub const AF_NOTIFY: ::c_int = 8;
 pub const AF_LOCAL: ::c_int = 9;
 pub const AF_UNIX: ::c_int = AF_LOCAL;
 pub const AF_BLUETOOTH: ::c_int = 10;
+#[doc(hidden)]
+#[deprecated(
+    since = "0.2.55",
+    note = "If you are using this report to: \
+            https://github.com/rust-lang/libc/issues/665"
+)]
 pub const AF_MAX: ::c_int = 11;
 
 pub const IP_OPTIONS: ::c_int = 1;
diff --git a/src/unix/notbsd/android/mod.rs b/src/unix/notbsd/android/mod.rs
index bab0218b6bf89ddd9d04ea5b2bfb77e1c48cb945..14800f8f9e40dbe976ce13ea4d815f7cd6f59dde 100644
--- a/src/unix/notbsd/android/mod.rs
+++ b/src/unix/notbsd/android/mod.rs
@@ -918,8 +918,19 @@ pub const SOL_NETROM: ::c_int = 259;
 pub const SOL_ROSE: ::c_int = 260;
 
 #[doc(hidden)]
+#[deprecated(
+    since = "0.2.55",
+    note = "If you are using this report to: \
+            https://github.com/rust-lang/libc/issues/665"
+)]
 pub const AF_MAX: ::c_int = 43;
 #[doc(hidden)]
+#[deprecated(
+    since = "0.2.55",
+    note = "If you are using this report to: \
+            https://github.com/rust-lang/libc/issues/665"
+)]
+#[allow(deprecated)]
 pub const PF_MAX: ::c_int = AF_MAX;
 
 /* DCCP socket options */
diff --git a/src/unix/notbsd/emscripten/mod.rs b/src/unix/notbsd/emscripten/mod.rs
index 07a2054561d9958dd79f49bd08b7265bbc3e31d4..78716aaa02aab70776b904c0f0408beb14ee29ca 100644
--- a/src/unix/notbsd/emscripten/mod.rs
+++ b/src/unix/notbsd/emscripten/mod.rs
@@ -922,12 +922,23 @@ pub const AF_MPLS: ::c_int = 28;
 pub const AF_NFC: ::c_int = 39;
 pub const AF_VSOCK: ::c_int = 40;
 #[doc(hidden)]
+#[deprecated(
+    since = "0.2.55",
+    note = "If you are using this report to: \
+            https://github.com/rust-lang/libc/issues/665"
+)]
 pub const AF_MAX: ::c_int = 42;
 pub const PF_IB: ::c_int = AF_IB;
 pub const PF_MPLS: ::c_int = AF_MPLS;
 pub const PF_NFC: ::c_int = AF_NFC;
 pub const PF_VSOCK: ::c_int = AF_VSOCK;
 #[doc(hidden)]
+#[allow(deprecated)]
+#[deprecated(
+    since = "0.2.55",
+    note = "If you are using this report to: \
+            https://github.com/rust-lang/libc/issues/665"
+)]
 pub const PF_MAX: ::c_int = AF_MAX;
 
 // System V IPC
diff --git a/src/unix/notbsd/linux/mips/mod.rs b/src/unix/notbsd/linux/mips/mod.rs
index 083572a2c6c424d2b36eb123c5ae3769465ae801..87d11864ff682a32dbe9991eb49eb6e0798e860e 100644
--- a/src/unix/notbsd/linux/mips/mod.rs
+++ b/src/unix/notbsd/linux/mips/mod.rs
@@ -895,8 +895,19 @@ pub const NFT_NG_INCREMENTAL: ::c_int = 0;
 pub const NFT_NG_RANDOM: ::c_int = 1;
 
 #[doc(hidden)]
+#[deprecated(
+    since = "0.2.55",
+    note = "If you are using this report to: \
+            https://github.com/rust-lang/libc/issues/665"
+)]
 pub const AF_MAX: ::c_int = 45;
 #[doc(hidden)]
+#[deprecated(
+    since = "0.2.55",
+    note = "If you are using this report to: \
+            https://github.com/rust-lang/libc/issues/665"
+)]
+#[allow(deprecated)]
 pub const PF_MAX: ::c_int = AF_MAX;
 
 f! {
diff --git a/src/unix/notbsd/linux/musl/b32/arm.rs b/src/unix/notbsd/linux/musl/b32/arm.rs
index c5feafc12dd648248ea3c0fb04dc7e212f081499..37c54150b7cdf4719331da38e6977f6d2e4ca4b0 100644
--- a/src/unix/notbsd/linux/musl/b32/arm.rs
+++ b/src/unix/notbsd/linux/musl/b32/arm.rs
@@ -839,6 +839,17 @@ pub const SYS_pkey_alloc: ::c_long = 395;
 pub const SYS_pkey_free: ::c_long = 396;
 
 #[doc(hidden)]
+#[deprecated(
+    since = "0.2.55",
+    note = "If you are using this report to: \
+            https://github.com/rust-lang/libc/issues/665"
+)]
 pub const AF_MAX: ::c_int = 45;
 #[doc(hidden)]
+#[allow(deprecated)]
+#[deprecated(
+    since = "0.2.55",
+    note = "If you are using this report to: \
+            https://github.com/rust-lang/libc/issues/665"
+)]
 pub const PF_MAX: ::c_int = AF_MAX;
diff --git a/src/unix/notbsd/linux/musl/b32/mips.rs b/src/unix/notbsd/linux/musl/b32/mips.rs
index 514c480eb0235739b8bab5a5e897fdeaca6b2531..a3ccc8ca2e589a5957987467530fa01fea7fb3dc 100644
--- a/src/unix/notbsd/linux/musl/b32/mips.rs
+++ b/src/unix/notbsd/linux/musl/b32/mips.rs
@@ -848,6 +848,17 @@ pub const SYS_preadv2: ::c_long = 4000 + 361;
 pub const SYS_pwritev2: ::c_long = 4000 + 362;
 
 #[doc(hidden)]
+#[deprecated(
+    since = "0.2.55",
+    note = "If you are using this report to: \
+            https://github.com/rust-lang/libc/issues/665"
+)]
 pub const AF_MAX: ::c_int = 42;
 #[doc(hidden)]
+#[deprecated(
+    since = "0.2.55",
+    note = "If you are using this report to: \
+            https://github.com/rust-lang/libc/issues/665"
+)]
+#[allow(deprecated)]
 pub const PF_MAX: ::c_int = AF_MAX;
diff --git a/src/unix/notbsd/linux/musl/b32/powerpc.rs b/src/unix/notbsd/linux/musl/b32/powerpc.rs
index f62cf6295d853c71e6c472b5b9dc66c92ba18d68..7e86be20a6b49a1723ab49dc1c0df7343920188c 100644
--- a/src/unix/notbsd/linux/musl/b32/powerpc.rs
+++ b/src/unix/notbsd/linux/musl/b32/powerpc.rs
@@ -865,6 +865,17 @@ pub const SYS_pkey_free: ::c_long = 385;
 pub const SYS_pkey_mprotect: ::c_long = 386;
 
 #[doc(hidden)]
+#[deprecated(
+    since = "0.2.55",
+    note = "If you are using this report to: \
+            https://github.com/rust-lang/libc/issues/665"
+)]
 pub const AF_MAX: ::c_int = 43;
 #[doc(hidden)]
+#[allow(deprecated)]
+#[deprecated(
+    since = "0.2.55",
+    note = "If you are using this report to: \
+            https://github.com/rust-lang/libc/issues/665"
+)]
 pub const PF_MAX: ::c_int = AF_MAX;
diff --git a/src/unix/notbsd/linux/musl/b32/x86.rs b/src/unix/notbsd/linux/musl/b32/x86.rs
index 95395f0a7afd0a7fdba04fba8bd32a056e5fce5a..191295a2bbd61ab6f4ad312c6aaf3c3649994a68 100644
--- a/src/unix/notbsd/linux/musl/b32/x86.rs
+++ b/src/unix/notbsd/linux/musl/b32/x86.rs
@@ -947,6 +947,17 @@ pub const UESP: ::c_int = 15;
 pub const SS: ::c_int = 16;
 
 #[doc(hidden)]
+#[deprecated(
+    since = "0.2.55",
+    note = "If you are using this report to: \
+            https://github.com/rust-lang/libc/issues/665"
+)]
 pub const AF_MAX: ::c_int = 45;
 #[doc(hidden)]
+#[allow(deprecated)]
+#[deprecated(
+    since = "0.2.55",
+    note = "If you are using this report to: \
+            https://github.com/rust-lang/libc/issues/665"
+)]
 pub const PF_MAX: ::c_int = AF_MAX;
diff --git a/src/unix/notbsd/linux/musl/b64/aarch64.rs b/src/unix/notbsd/linux/musl/b64/aarch64.rs
index af654e31a3864fbf51e0048f39be23e7105bef48..16cb46d557639cad5aa3f0acaac290b40aed55c9 100644
--- a/src/unix/notbsd/linux/musl/b64/aarch64.rs
+++ b/src/unix/notbsd/linux/musl/b64/aarch64.rs
@@ -71,8 +71,19 @@ pub const MINSIGSTKSZ: ::size_t = 6144;
 pub const SIGSTKSZ: ::size_t = 12288;
 
 #[doc(hidden)]
+#[deprecated(
+    since = "0.2.55",
+    note = "If you are using this report to: \
+            https://github.com/rust-lang/libc/issues/665"
+)]
 pub const PF_MAX: ::c_int = 45;
 #[doc(hidden)]
+#[deprecated(
+    since = "0.2.55",
+    note = "If you are using this report to: \
+            https://github.com/rust-lang/libc/issues/665"
+)]
+#[allow(deprecated)]
 pub const AF_MAX: ::c_int = PF_MAX;
 
 pub const MADV_SOFT_OFFLINE: ::c_int = 101;
diff --git a/src/unix/notbsd/linux/musl/b64/powerpc64.rs b/src/unix/notbsd/linux/musl/b64/powerpc64.rs
index 4230669087f22aeee88958c90a52f2114bdc36c1..4a8df270fc34c1a8cf53044d8efcd0cae3a39384 100644
--- a/src/unix/notbsd/linux/musl/b64/powerpc64.rs
+++ b/src/unix/notbsd/linux/musl/b64/powerpc64.rs
@@ -71,8 +71,19 @@ pub const SIGSTKSZ: ::size_t = 10240;
 pub const MINSIGSTKSZ: ::size_t = 4096;
 
 #[doc(hidden)]
+#[deprecated(
+    since = "0.2.55",
+    note = "If you are using this report to: \
+            https://github.com/rust-lang/libc/issues/665"
+)]
 pub const AF_MAX: ::c_int = 45;
 #[doc(hidden)]
+#[deprecated(
+    since = "0.2.55",
+    note = "If you are using this report to: \
+            https://github.com/rust-lang/libc/issues/665"
+)]
+#[allow(deprecated)]
 pub const PF_MAX: ::c_int = AF_MAX;
 
 // Syscall table
diff --git a/src/unix/notbsd/linux/musl/b64/x86_64.rs b/src/unix/notbsd/linux/musl/b64/x86_64.rs
index 3e2f1a435aea0fb72cbe80a084e8ebd0ad45d8cd..a055f60c133f8e7b29840a52a185a8c14eefd539 100644
--- a/src/unix/notbsd/linux/musl/b64/x86_64.rs
+++ b/src/unix/notbsd/linux/musl/b64/x86_64.rs
@@ -494,8 +494,19 @@ pub const SIGSTKSZ: ::size_t = 8192;
 pub const MINSIGSTKSZ: ::size_t = 2048;
 
 #[doc(hidden)]
+#[deprecated(
+    since = "0.2.55",
+    note = "If you are using this report to: \
+            https://github.com/rust-lang/libc/issues/665"
+)]
 pub const AF_MAX: ::c_int = 45;
 #[doc(hidden)]
+#[deprecated(
+    since = "0.2.55",
+    note = "If you are using this report to: \
+            https://github.com/rust-lang/libc/issues/665"
+)]
+#[allow(deprecated)]
 pub const PF_MAX: ::c_int = AF_MAX;
 
 pub const RLIMIT_NLIMITS: ::c_int = 15;
diff --git a/src/unix/notbsd/linux/other/mod.rs b/src/unix/notbsd/linux/other/mod.rs
index 26c9ad4c544a3311155b6fc4ae7d97a3149f329e..c875fa1006f067c76178a6496aa4bfb291755bb7 100644
--- a/src/unix/notbsd/linux/other/mod.rs
+++ b/src/unix/notbsd/linux/other/mod.rs
@@ -927,8 +927,19 @@ pub const M_ARENA_TEST: ::c_int = -7;
 pub const M_ARENA_MAX: ::c_int = -8;
 
 #[doc(hidden)]
+#[deprecated(
+    since = "0.2.55",
+    note = "If you are using this report to: \
+            https://github.com/rust-lang/libc/issues/665"
+)]
 pub const AF_MAX: ::c_int = 45;
 #[doc(hidden)]
+#[deprecated(
+    since = "0.2.55",
+    note = "If you are using this report to: \
+            https://github.com/rust-lang/libc/issues/665"
+)]
+#[allow(deprecated)]
 pub const PF_MAX: ::c_int = AF_MAX;
 
 cfg_if! {
diff --git a/src/unix/solarish/mod.rs b/src/unix/solarish/mod.rs
index de7c1cde8e58900796a91895628bc1f7d8b8c55f..b50c6471a8514f4598018d844c67e86b224aae57 100644
--- a/src/unix/solarish/mod.rs
+++ b/src/unix/solarish/mod.rs
@@ -1175,6 +1175,13 @@ pub const AF_INET_OFFLOAD: ::c_int = 30;
 pub const AF_TRILL: ::c_int = 31;
 pub const AF_PACKET: ::c_int = 32;
 pub const AF_LX_NETLINK: ::c_int = 33;
+
+#[doc(hidden)]
+#[deprecated(
+    since = "0.2.55",
+    note = "If you are using this report to: \
+            https://github.com/rust-lang/libc/issues/665"
+)]
 pub const AF_MAX: ::c_int = 33;
 pub const SOCK_DGRAM: ::c_int = 1;
 pub const SOCK_STREAM: ::c_int = 2;
diff --git a/src/unix/uclibc/mod.rs b/src/unix/uclibc/mod.rs
index 3fd64ca28130a80e3b3637fac17028a08f918915..95848fd42f53f62ce7d24ed867460bf511eed1ad 100644
--- a/src/unix/uclibc/mod.rs
+++ b/src/unix/uclibc/mod.rs
@@ -1445,6 +1445,11 @@ pub const NOSTR: ::nl_item = 0x503;
 
 pub const FILENAME_MAX: ::c_uint = 4095;
 
+#[deprecated(
+    since = "0.2.55",
+    note = "If you are using this report to: \
+            https://github.com/rust-lang/libc/issues/665"
+)]
 pub const AF_MAX: ::c_int = 39;
 
 f! {