-void *xclone (void const *p, size_t s);
-char *xstrdup (const char *str);
-
-/* These macros are deprecated; they will go away soon, and are retained
- temporarily only to ease conversion to the functions described above. */
-# define CCLONE(p, n) xclone (p, (n) * sizeof *(p))
-# define CLONE(p) xclone (p, sizeof *(p))
-# define NEW(type, var) type *var = xmalloc (sizeof (type))
-# define XCALLOC(type, n) xcalloc (n, sizeof (type))
-# define XMALLOC(type, n) xnmalloc (n, sizeof (type))
-# define XREALLOC(p, type, n) xnrealloc (p, n, sizeof (type))
-# define XFREE(p) free (p)
+void *x2realloc (void *p, size_t *pn);
+void *x2nrealloc (void *p, size_t *pn, size_t s);
+void *xmemdup (void const *p, size_t s);
+char *xstrdup (char const *str);
+
+/* Return 1 if an array of N objects, each of size S, cannot exist due
+ to size arithmetic overflow. S must be positive and N must be
+ nonnegative. This is a macro, not an inline function, so that it
+ works correctly even when SIZE_MAX < N.
+
+ By gnulib convention, SIZE_MAX represents overflow in size
+ calculations, so the conservative dividend to use here is
+ SIZE_MAX - 1, since SIZE_MAX might represent an overflowed value.
+ However, malloc (SIZE_MAX) fails on all known hosts where
+ sizeof (ptrdiff_t) <= sizeof (size_t), so do not bother to test for
+ exactly-SIZE_MAX allocations on such hosts; this avoids a test and
+ branch when S is known to be 1. */
+# define xalloc_oversized(n, s) \
+ ((size_t) (sizeof (ptrdiff_t) <= sizeof (size_t) ? -1 : -2) / (s) < (n))
+
+# ifdef __cplusplus
+}
+# endif
+