+#ifndef ATTRIBUTE_UNUSED
+# define ATTRIBUTE_UNUSED __attribute__ ((__unused__))
+#endif
+
+#define FUNCTION_PRINT() fprintf (stderr, "%s: ", __func__)
+
+/*------.
+| NLS. |
+`------*/
+
+#include <locale.h>
+
+#include <gettext.h>
+#define _(Msgid) gettext (Msgid)
+#define N_(Msgid) (Msgid)
+
+
+/*-----------.
+| Booleans. |
+`-----------*/
+
+#include <stdbool.h>
+
+
+
+/*-------------.
+| Assertions. |
+`-------------*/
+
+/* In the past, Bison defined aver to simply invoke abort in the case of
+ a failed assertion. The rationale was that <assert.h>'s assertions
+ were too heavyweight and could be disabled too easily. See
+ discussions at
+ <http://lists.gnu.org/archive/html/bison-patches/2006-01/msg00080.html>
+ <http://lists.gnu.org/archive/html/bison-patches/2006-09/msg00111.html>.
+
+ However, normal assert output can be helpful during development and
+ in bug reports from users. Moreover, it's not clear now that
+ <assert.h>'s assertions are significantly heavyweight. Finally, if
+ users want to experiment with disabling assertions, it's debatable
+ whether it's our responsibility to stop them. See discussion
+ starting at
+ <http://lists.gnu.org/archive/html/bison-patches/2009-09/msg00013.html>.
+
+ For now, we use assert but we call it aver throughout Bison in case
+ we later wish to try another scheme.
+*/
+#include <assert.h>
+#define aver assert
+
+
+/*-----------.
+| Obstacks. |
+`-----------*/
+
+#define obstack_chunk_alloc xmalloc
+#define obstack_chunk_free free
+#include <obstack.h>
+
+#define obstack_sgrow(Obs, Str) \
+ obstack_grow (Obs, Str, strlen (Str))
+
+#define obstack_fgrow1(Obs, Format, Arg1) \
+do { \
+ char buf[4096]; \
+ sprintf (buf, Format, Arg1); \
+ obstack_grow (Obs, buf, strlen (buf)); \
+} while (0)
+
+#define obstack_fgrow2(Obs, Format, Arg1, Arg2) \
+do { \
+ char buf[4096]; \
+ sprintf (buf, Format, Arg1, Arg2); \
+ obstack_grow (Obs, buf, strlen (buf)); \
+} while (0)
+
+#define obstack_fgrow3(Obs, Format, Arg1, Arg2, Arg3) \
+do { \
+ char buf[4096]; \
+ sprintf (buf, Format, Arg1, Arg2, Arg3); \
+ obstack_grow (Obs, buf, strlen (buf)); \
+} while (0)
+
+#define obstack_fgrow4(Obs, Format, Arg1, Arg2, Arg3, Arg4) \
+do { \
+ char buf[4096]; \
+ sprintf (buf, Format, Arg1, Arg2, Arg3, Arg4); \
+ obstack_grow (Obs, buf, strlen (buf)); \
+} while (0)
+
+
+
+/*-----------------------------------------.
+| Extensions to use for the output files. |
+`-----------------------------------------*/
+
+#ifndef OUTPUT_EXT
+# define OUTPUT_EXT ".output"