Index: include/protocols/dumprestore.h
===================================================================
--- include/protocols/dumprestore.h
+++ include/protocols/dumprestore.h
@@ -76,7 +76,11 @@
  */
 typedef uint32_t dump_ino_t;
 
-union u_spcl {
+/*
+ * The instance of union u_spcl declared here is explicitly not defined in any
+ * library; your application including this header must define it as needed.
+ */
+extern union u_spcl {
 	char dummy[TP_BSIZE];
 	struct	s_spcl {
 		int32_t	c_type;		    /* record type (see below) */
Index: sbin/dump/tape.c
===================================================================
--- sbin/dump/tape.c
+++ sbin/dump/tape.c
@@ -72,6 +72,8 @@
 char	*nexttape;
 FILE	*popenfp = NULL;
 
+union u_spcl	u_spcl;
+
 static	int atomic(ssize_t (*)(), int, char *, int);
 static	void doslave(int, int);
 static	void enslave(void);
Index: sbin/restore/tape.c
===================================================================
--- sbin/restore/tape.c
+++ sbin/restore/tape.c
@@ -94,6 +94,8 @@
 static char	lnkbuf[MAXPATHLEN + 1];
 static int	pathlen;
 
+union u_spcl	u_spcl;
+
 int		Bcvt;		/* Swap Bytes */
 int		oldinofmt;	/* FreeBSD 1 inode format needs cvt */