diff --git a/tools/build/fspacectl.c b/tools/build/fspacectl.c
index c17802c51e01..13abca23a318 100644
--- a/tools/build/fspacectl.c
+++ b/tools/build/fspacectl.c
@@ -1,44 +1,45 @@
 /*-
  * Copyright (c) 2021 The FreeBSD Foundation
  *
  * This software was developed by Ka Ho Ng <khng@FreeBSD.org>
  * under sponsorship from the FreeBSD Foundation.
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions
  * are met:
  * 1. Redistributions of source code must retain the above copyright
  *    notice, this list of conditions and the following disclaimer.
  * 2. Redistributions in binary form must reproduce the above copyright
  *    notice, this list of conditions and the following disclaimer in the
  *    documentation and/or other materials provided with the distribution.
  *
  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  * SUCH DAMAGE.
  */
 
 #include <sys/cdefs.h>
 __FBSDID("$FreeBSD$");
 
 #include <errno.h>
 #include <fcntl.h>
 
 /*
  * This is currently a stub implementation of fspacectl(2).
  */
 int
-fspacectl(int fd, int cmd, const struct spacectl_range *rqsr, int flags,
-    struct spacectl_range *rmsr)
+fspacectl(int fd __unused, int cmd __unused,
+    const struct spacectl_range *rqsr __unused, int flags __unused,
+    struct spacectl_range *rmsr __unused)
 {
-        errno = ENOSYS;
-        return (-1);
-}
\ No newline at end of file
+	errno = ENOSYS;
+	return (-1);
+}