+static inline char *
+obstack_strdup (struct obstack *obstackp, const char *string)
+{
+ return (char *) obstack_copy0 (obstackp, string, strlen (string));
+}
+
+/* Duplicate STRING, returning an equivalent string that's allocated on the
+ obstack OBSTACKP. */
+
+static inline char *
+obstack_strdup (struct obstack *obstackp, const std::string &string)
+{
+ return (char *) obstack_copy0 (obstackp, string.c_str (),
+ string.size ());
+}
+
+/* Duplicate the first N characters of STRING, returning a
+ \0-terminated string that's allocated on the obstack OBSTACKP.
+ Note that exactly N characters are copied, even if STRING is
+ shorter. */
+
+static inline char *
+obstack_strndup (struct obstack *obstackp, const char *string, size_t n)
+{
+ return (char *) obstack_copy0 (obstackp, string, n);
+}
+
+/* An obstack that frees itself on scope exit. */
+struct auto_obstack : obstack
+{
+ auto_obstack ()
+ { obstack_init (this); }
+
+ ~auto_obstack ()
+ { obstack_free (this, NULL); }
+
+ DISABLE_COPY_AND_ASSIGN (auto_obstack);
+
+ /* Free all memory in the obstack but leave it valid for further
+ allocation. */
+ void clear ()
+ { obstack_free (this, obstack_base (this)); }
+};
+
+/* Objects are allocated on obstack instead of heap. */
+
+struct allocate_on_obstack
+{
+ allocate_on_obstack () = default;
+
+ void* operator new (size_t size, struct obstack *obstack)
+ {
+ return obstack_alloc (obstack, size);
+ }
+
+ void* operator new[] (size_t size, struct obstack *obstack)
+ {
+ return obstack_alloc (obstack, size);
+ }
+
+ void operator delete (void *memory) {}
+ void operator delete[] (void *memory) {}
+};