diff --git a/libc-test/build.rs b/libc-test/build.rs
index b87594bbafff61d7969d8e15b6dd550d31e570ff..5446a30022947b01b039ffb63b6ffefe3fcf3cfe 100644
--- a/libc-test/build.rs
+++ b/libc-test/build.rs
@@ -630,6 +630,7 @@ fn do_ctest() {
             | "RENAME_NOREPLACE"
             | "RENAME_EXCHANGE"
             | "RENAME_WHITEOUT"
+            // ALG_SET_AEAD_* constants are available starting from kernel 3.19
             | "ALG_SET_AEAD_ASSOCLEN"
             | "ALG_SET_AEAD_AUTHSIZE"
                 if musl =>