diff --git a/library/std/src/sys/pal/unix/mod.rs b/library/std/src/sys/pal/unix/mod.rs
index 21f233e22620c..c38dc16c902b9 100644
--- a/library/std/src/sys/pal/unix/mod.rs
+++ b/library/std/src/sys/pal/unix/mod.rs
@@ -262,7 +262,6 @@ pub fn decode_error_kind(errno: i32) -> ErrorKind {
         libc::ENOENT => NotFound,
         libc::ENOMEM => OutOfMemory,
         libc::ENOSPC => StorageFull,
-        libc::ENOSYS => Unsupported,
         libc::EMLINK => TooManyLinks,
         libc::ENAMETOOLONG => InvalidFilename,
         libc::ENETDOWN => NetworkDown,
@@ -286,6 +285,10 @@ pub fn decode_error_kind(errno: i32) -> ErrorKind {
         // clause
         x if x == libc::EAGAIN || x == libc::EWOULDBLOCK => WouldBlock,
 
+        // `ENOTSUP` and `EOPNOTSUPP` can also have the same value,
+        // so we can't use a match clause.
+        x if x == libc::ENOTSUP || x == libc::EOPNOTSUPP || x == libc::ENOSYS => Unsupported,
+
         _ => Uncategorized,
     }
 }