diff --git a/src/3rdparty/forkfd/forkfd.c b/src/3rdparty/forkfd/forkfd.c
index edef3c5bcc8..072e4adbc8a 100644
--- a/src/3rdparty/forkfd/forkfd.c
+++ b/src/3rdparty/forkfd/forkfd.c
@@ -35,7 +35,7 @@
 //#define FORKFD_DISABLE_FORK_FALLBACK 1    /* disable falling back to fork() from system_forkfd() */
 
 #include <sys/types.h>
-#if defined(__OpenBSD__) || defined(__NetBSD__)
+#if defined(__OpenBSD__) || defined(__NetBSD__) || defined(__FreeBSD__)
 #  include <sys/param.h>
 #endif
 #include <sys/time.h>
@@ -75,6 +75,7 @@
 #if (defined(__FreeBSD__) && defined(__FreeBSD_version) && __FreeBSD_version >= 1300000)
 #  include <sys/eventfd.h>
 #  define HAVE_EVENTFD 1
+#  define HAVE_WAITID   1
 #endif
 #if (defined(__FreeBSD__) && defined(__FreeBSD_version) && __FreeBSD_version >= 1000032) || \
     (defined(__OpenBSD__) && OpenBSD >= 201505) || \
diff --git a/src/3rdparty/forkfd/forkfd_freebsd.c b/src/3rdparty/forkfd/forkfd_freebsd.c
index ba18d835915..9cb327835c3 100644
--- a/src/3rdparty/forkfd/forkfd_freebsd.c
+++ b/src/3rdparty/forkfd/forkfd_freebsd.c
@@ -31,6 +31,10 @@
 
 #undef SYSTEM_FORKFD_CAN_VFORK
 
+#ifndef HAVE_WAITID
+#  error Need waitid() API
+#endif
+
 // in forkfd.c
 static int convertForkfdWaitFlagsToWaitFlags(int ffdoptions);
 static void convertStatusToForkfdInfo(int status, struct forkfd_info *info);