--- /dev/null
+/* Allow this file to be included multiple times
+ with different settings of NDEBUG. */
+#undef assert
+#undef __assert
+
+#ifdef NDEBUG
+#define assert(ignore) ((void) 0)
+#else
+
+#ifndef __GNUC__
+
+#define assert(expression) \
+ ((void) ((expression) ? 0 : __assert (expression, __FILE__, __LINE__)))
+
+#define __assert(expression, file, lineno) \
+ (printf ("%s:%d: failed assertion\n", file, lineno), \
+ abort (), 0)
+
+#else
+void __eprintf (); /* Defined in libgcc.a */
+
+#ifdef __STDC__
+
+#define assert(expression) \
+ ((void) ((expression) ? 0 : __assert (#expression, __FILE__, __LINE__)))
+
+#define __assert(expression, file, line) \
+ (__eprintf ("%s:%d: failed assertion `%s'\n", \
+ file, line, expression), 0)
+
+#else /* no __STDC__; i.e. -traditional. */
+
+#define assert(expression) \
+ ((void) ((expression) ? 0 : __assert (expression, __FILE__, __LINE__)))
+
+#define __assert(expression, file, lineno) \
+ (__eprintf ("%s:%d: failed assertion `%s'\n", \
+ file, lineno, "expression"), 0)
+
+#endif /* no __STDC__; i.e. -traditional. */
+#endif /* no __GNU__; i.e., /bin/cc. */
+#endif