diff --git a/cmd/zfs/zfs_main.c b/cmd/zfs/zfs_main.c
index 84f69f4e26..2a54609747 100644
--- a/cmd/zfs/zfs_main.c
+++ b/cmd/zfs/zfs_main.c
@@ -751,6 +751,8 @@ note_dev_error(int err, int fd)
 		    "(As a workaround, "
 		    "try \"zfs send [...] | cat > /dev/null\")\n"));
 	}
+#else
+	(void) err, (void) fd;
 #endif
 }
 
diff --git a/contrib/pam_zfs_key/pam_zfs_key.c b/contrib/pam_zfs_key/pam_zfs_key.c
index 9702189f67..f831f65af1 100644
--- a/contrib/pam_zfs_key/pam_zfs_key.c
+++ b/contrib/pam_zfs_key/pam_zfs_key.c
@@ -47,6 +47,7 @@
 static void
 pam_syslog(pam_handle_t *pamh, int loglevel, const char *fmt, ...)
 {
+	(void) pamh;
 	va_list args;
 	va_start(args, fmt);
 	vsyslog(loglevel, fmt, args);
diff --git a/lib/libshare/os/freebsd/nfs.c b/lib/libshare/os/freebsd/nfs.c
index 494442cb52..ea02dc1bae 100644
--- a/lib/libshare/os/freebsd/nfs.c
+++ b/lib/libshare/os/freebsd/nfs.c
@@ -155,6 +155,7 @@ nfs_is_shared(sa_share_impl_t impl_share)
 static int
 nfs_validate_shareopts(const char *shareopts)
 {
+	(void) shareopts;
 	return (SA_OK);
 }
 
diff --git a/lib/libshare/os/freebsd/smb.c b/lib/libshare/os/freebsd/smb.c
index 5b606ab969..a25990d3bf 100644
--- a/lib/libshare/os/freebsd/smb.c
+++ b/lib/libshare/os/freebsd/smb.c
@@ -47,6 +47,7 @@ static sa_fstype_t *smb_fstype;
 static int
 smb_enable_share(sa_share_impl_t impl_share)
 {
+	(void) impl_share;
 	fprintf(stderr, "No SMB support in FreeBSD yet.\n");
 	return (SA_NOT_SUPPORTED);
 }
@@ -56,6 +57,7 @@ smb_enable_share(sa_share_impl_t impl_share)
 static int
 smb_disable_share(sa_share_impl_t impl_share)
 {
+	(void) impl_share;
 	fprintf(stderr, "No SMB support in FreeBSD yet.\n");
 	return (SA_NOT_SUPPORTED);
 }
@@ -66,6 +68,7 @@ smb_disable_share(sa_share_impl_t impl_share)
 static int
 smb_validate_shareopts(const char *shareopts)
 {
+	(void) shareopts;
 	fprintf(stderr, "No SMB support in FreeBSD yet.\n");
 	return (SA_NOT_SUPPORTED);
 }
@@ -76,6 +79,7 @@ smb_validate_shareopts(const char *shareopts)
 static boolean_t
 smb_is_share_active(sa_share_impl_t impl_share)
 {
+	(void) impl_share;
 	return (B_FALSE);
 }
 
@@ -88,6 +92,7 @@ smb_is_share_active(sa_share_impl_t impl_share)
 static int
 smb_update_shareopts(sa_share_impl_t impl_share, const char *shareopts)
 {
+	(void) impl_share, (void) shareopts;
 	return (SA_OK);
 }
 
diff --git a/lib/libspl/include/sys/simd.h b/lib/libspl/include/sys/simd.h
index dceedb698f..6ef836c16e 100644
--- a/lib/libspl/include/sys/simd.h
+++ b/lib/libspl/include/sys/simd.h
@@ -468,6 +468,7 @@ zfs_avx512vbmi_available(void)
 static jmp_buf env;
 static void sigillhandler(int x)
 {
+	(void) x;
 	longjmp(env, 1);
 }
 #endif
diff --git a/lib/libzfs/os/freebsd/libzfs_compat.c b/lib/libzfs/os/freebsd/libzfs_compat.c
index e3f17662a1..cb5a27c64f 100644
--- a/lib/libzfs/os/freebsd/libzfs_compat.c
+++ b/lib/libzfs/os/freebsd/libzfs_compat.c
@@ -42,6 +42,7 @@ void
 libzfs_set_pipe_max(int infd)
 {
 	/* FreeBSD automatically resizes */
+	(void) infd;
 }
 
 static int
@@ -251,24 +252,28 @@ libzfs_load_module(void)
 int
 zpool_relabel_disk(libzfs_handle_t *hdl, const char *path, const char *msg)
 {
+	(void) hdl, (void) path, (void) msg;
 	return (0);
 }
 
 int
 zpool_label_disk(libzfs_handle_t *hdl, zpool_handle_t *zhp, const char *name)
 {
+	(void) hdl, (void) zhp, (void) name;
 	return (0);
 }
 
 int
 find_shares_object(differ_info_t *di)
 {
+	(void) di;
 	return (0);
 }
 
 int
 zfs_destroy_snaps_nvl_os(libzfs_handle_t *hdl, nvlist_t *snaps)
 {
+	(void) hdl, (void) snaps;
 	return (0);
 }