diff --git a/libc-test/semver/redox.txt b/libc-test/semver/redox.txt
index 475e96bdd9a29..4169bb79a24fd 100644
--- a/libc-test/semver/redox.txt
+++ b/libc-test/semver/redox.txt
@@ -100,6 +100,11 @@ IPV6_ADD_MEMBERSHIP
 IPV6_DROP_MEMBERSHIP
 IUCLC
 IUTF8
+MADV_DONTNEED
+MADV_NORMAL
+MADV_RANDOM
+MADV_SEQUENTIAL
+MADV_WILLNEED
 MSG_DONTWAIT
 NI_DGRAM
 NI_MAXSERV
diff --git a/src/unix/redox/mod.rs b/src/unix/redox/mod.rs
index 02beda431277e..3bb7b044d0c1b 100644
--- a/src/unix/redox/mod.rs
+++ b/src/unix/redox/mod.rs
@@ -634,6 +634,12 @@ pub const PROT_READ: ::c_int = 0x0004;
 pub const PROT_WRITE: ::c_int = 0x0002;
 pub const PROT_EXEC: ::c_int = 0x0001;
 
+pub const MADV_NORMAL: ::c_int = 0;
+pub const MADV_RANDOM: ::c_int = 1;
+pub const MADV_SEQUENTIAL: ::c_int = 2;
+pub const MADV_WILLNEED: ::c_int = 3;
+pub const MADV_DONTNEED: ::c_int = 4;
+
 pub const MAP_SHARED: ::c_int = 0x0001;
 pub const MAP_PRIVATE: ::c_int = 0x0002;
 pub const MAP_ANON: ::c_int = 0x0020;