+/* Used to print pointers (usually for debugging). Print pointers
+ using printf ("%0*lx", PTR_FORMAT (p)). (%p is too unpredictable;
+ some implementations prepend 0x, while some don't, and most don't
+ 0-pad the address.) */
+#define PTR_FORMAT(p) 2 * sizeof (void *), (unsigned long) (p)
+