--- /Users/Jess/Git/kqueue.rs.orig	2021-09-13 01:21:21.533163744 +0100
+++ /Users/Jess/.cargo/registry/src/github.com-1ecc6299db9ec823/mio-0.7.13//src/sys/unix/selector/kqueue.rs	2021-09-13 01:43:33.071089985 +0100
@@ -51,6 +51,8 @@
 #[cfg(target_os = "netbsd")]
 type UData = libc::intptr_t;
 
+// FreeBSD 12 added uint64_t ext[4], and RISC-V first appeared in FreeBSD 12 so
+// the libc crate uses the FreeBSD 12 ABI
 macro_rules! kevent {
     ($id: expr, $filter: expr, $flags: expr, $data: expr) => {
         libc::kevent {
@@ -60,6 +62,8 @@
             fflags: 0,
             data: 0,
             udata: $data as UData,
+            #[cfg(all(target_os = "freebsd", target_arch = "riscv64"))]
+            ext: [0; 4],
         }
     };
 }