diff --git a/Cargo.lock b/Cargo.lock
index 1875b0e..19d2108 100644
--- a/Cargo.lock
+++ b/Cargo.lock
@@ -2,8 +2,8 @@
 name = "libc-test"
 version = "0.1.0"
 dependencies = [
- "ctest 0.1.0 (registry+https://github.com/rust-lang/crates.io-index)",
- "libc 0.2.22",
+ "ctest 0.1.1 (registry+https://github.com/rust-lang/crates.io-index)",
+ "libc 0.2.23",
 ]
 
 [[package]]
@@ -13,23 +13,23 @@
 
 [[package]]
 name = "ctest"
-version = "0.1.0"
+version = "0.1.1"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 dependencies = [
- "gcc 0.3.35 (registry+https://github.com/rust-lang/crates.io-index)",
+ "gcc 0.3.46 (registry+https://github.com/rust-lang/crates.io-index)",
  "syntex_syntax 0.19.1 (registry+https://github.com/rust-lang/crates.io-index)",
 ]
 
 [[package]]
 name = "gcc"
-version = "0.3.35"
+version = "0.3.46"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 
 [[package]]
 name = "generate-files"
 version = "0.1.0"
 dependencies = [
- "ctest 0.1.0 (registry+https://github.com/rust-lang/crates.io-index)",
+ "ctest 0.1.1 (registry+https://github.com/rust-lang/crates.io-index)",
 ]
 
 [[package]]
@@ -48,16 +48,16 @@
 
 [[package]]
 name = "libc"
-version = "0.2.22"
+version = "0.2.23"
 
 [[package]]
 name = "log"
-version = "0.3.6"
+version = "0.3.7"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 
 [[package]]
 name = "rustc-serialize"
-version = "0.3.19"
+version = "0.3.24"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 
 [[package]]
@@ -67,8 +67,8 @@
 dependencies = [
  "bitflags 0.3.3 (registry+https://github.com/rust-lang/crates.io-index)",
  "libc 0.1.12 (registry+https://github.com/rust-lang/crates.io-index)",
- "log 0.3.6 (registry+https://github.com/rust-lang/crates.io-index)",
- "rustc-serialize 0.3.19 (registry+https://github.com/rust-lang/crates.io-index)",
+ "log 0.3.7 (registry+https://github.com/rust-lang/crates.io-index)",
+ "rustc-serialize 0.3.24 (registry+https://github.com/rust-lang/crates.io-index)",
  "term 0.2.14 (registry+https://github.com/rust-lang/crates.io-index)",
  "unicode-xid 0.0.3 (registry+https://github.com/rust-lang/crates.io-index)",
 ]
@@ -99,12 +99,12 @@
 
 [metadata]
 "checksum bitflags 0.3.3 (registry+https://github.com/rust-lang/crates.io-index)" = "32866f4d103c4e438b1db1158aa1b1a80ee078e5d77a59a2f906fd62a577389c"
-"checksum ctest 0.1.0 (registry+https://github.com/rust-lang/crates.io-index)" = "0d8e8e44b9fb51a835b9193863b4b873dea29756cf4ba5151c0a6cc0f15fbdeb"
-"checksum gcc 0.3.35 (registry+https://github.com/rust-lang/crates.io-index)" = "91ecd03771effb0c968fd6950b37e89476a578aaf1c70297d8e92b6516ec3312"
+"checksum ctest 0.1.1 (registry+https://github.com/rust-lang/crates.io-index)" = "156b2ddc97c727423b94749e91562244a093e345a575fe1b6b589ab194e09a72"
+"checksum gcc 0.3.46 (registry+https://github.com/rust-lang/crates.io-index)" = "181e3cebba1d663bd92eb90e2da787e10597e027eb00de8d742b260a7850948f"
 "checksum kernel32-sys 0.2.2 (registry+https://github.com/rust-lang/crates.io-index)" = "7507624b29483431c0ba2d82aece8ca6cdba9382bff4ddd0f7490560c056098d"
 "checksum libc 0.1.12 (registry+https://github.com/rust-lang/crates.io-index)" = "e32a70cf75e5846d53a673923498228bbec6a8624708a9ea5645f075d6276122"
-"checksum log 0.3.6 (registry+https://github.com/rust-lang/crates.io-index)" = "ab83497bf8bf4ed2a74259c1c802351fcd67a65baa86394b6ba73c36f4838054"
-"checksum rustc-serialize 0.3.19 (registry+https://github.com/rust-lang/crates.io-index)" = "6159e4e6e559c81bd706afe9c8fd68f547d3e851ce12e76b1de7914bab61691b"
+"checksum log 0.3.7 (registry+https://github.com/rust-lang/crates.io-index)" = "5141eca02775a762cc6cd564d8d2c50f67c0ea3a372cbf1c51592b3e029e10ad"
+"checksum rustc-serialize 0.3.24 (registry+https://github.com/rust-lang/crates.io-index)" = "dcf128d1287d2ea9d80910b5f1120d0b8eede3fbf1abe91c40d39ea7d51e6fda"
 "checksum syntex_syntax 0.19.1 (registry+https://github.com/rust-lang/crates.io-index)" = "8739e1a8b53efe7349917259f8ced15f797c89bf788a86e44f61addc0d1ecf68"
 "checksum term 0.2.14 (registry+https://github.com/rust-lang/crates.io-index)" = "f2077e54d38055cf1ca0fd7933a2e00cd3ec8f6fed352b2a377f06dcdaaf3281"
 "checksum unicode-xid 0.0.3 (registry+https://github.com/rust-lang/crates.io-index)" = "36dff09cafb4ec7c8cf0023eb0b686cb6ce65499116a12201c9e11840ca01beb"
diff --git a/Cargo.toml b/Cargo.toml
index 2362eec..3914fd6 100644
--- a/Cargo.toml
+++ b/Cargo.toml
@@ -1,7 +1,7 @@
 [package]
 
 name = "libc"
-version = "0.2.22"
+version = "0.2.23"
 authors = ["The Rust Project Developers"]
 license = "MIT/Apache-2.0"
 readme = "README.md"
diff --git a/libc-test/build.rs b/libc-test/build.rs
index b08bcce..6506d8d 100644
--- a/libc-test/build.rs
+++ b/libc-test/build.rs
@@ -404,6 +404,10 @@
             "MADV_MERGEABLE" | "MADV_UNMERGEABLE" | "MADV_HWPOISON" | "IPV6_ADD_MEMBERSHIP" | "IPV6_DROP_MEMBERSHIP" | "IPV6_MULTICAST_LOOP" | "IPV6_V6ONLY" |
             "MAP_STACK" | "RTLD_DEEPBIND" | "SOL_IPV6" | "SOL_ICMPV6" if uclibc => true,
 
+            // Defined by libattr not libc on linux (hard to test).
+            // See constant definition for more details.
+            "ENOATTR" if linux => true,
+
             _ => false,
         }
     });
diff --git a/src/unix/notbsd/linux/mod.rs b/src/unix/notbsd/linux/mod.rs
index 1d308a3..b9375a3 100644
--- a/src/unix/notbsd/linux/mod.rs
+++ b/src/unix/notbsd/linux/mod.rs
@@ -700,6 +700,11 @@
 pub const XATTR_CREATE: ::c_int = 0x1;
 pub const XATTR_REPLACE: ::c_int = 0x2;
 
+// On Linux, libc doesn't define this constant, libattr does instead.
+// We still define it for Linux as it's defined by libc on other platforms,
+// and it's mentioned in the man pages for getxattr and setxattr.
+pub const ENOATTR: ::c_int = ::ENODATA;
+
 f! {
     pub fn CPU_ZERO(cpuset: &mut cpu_set_t) -> () {
         for slot in cpuset.bits.iter_mut() {