protect against multiple inclusion

include/_tail_cc/assert.h

@@ -5,6 +5,9 @@
 /* $Header$ */
 /*	 A S S E R T I O N    M A C R O   D E F I N I T I O N		*/
 
+#ifndef _ASSERT_H
+#define _ASSERT_H
+
 #ifndef	NDEBUG
 /*	Note: this macro uses parameter substitution inside strings */
 #define	assert(exp)	(exp || (fprintf(stderr,"Assertion \"%s\" failed: file %s, line %d\n", "exp", __FILE__, __LINE__), exit(1)))
@@ -13,3 +16,4 @@
 #define	assert(exp)	(1)
 #define _assert(exp)	(1)
 #endif	NDEBUG
+#endif /* _ASSERT_H */