+struct obstack output_obstack;
+
+/* Initializing some values below (such SPEC_NAME_PREFIX to `yy') is
+ tempting, but don't do that: for the time being our handling of the
+ %directive vs --option leaves precedence to the options by deciding
+ that if a %directive sets a variable which is really set (i.e., not
+ NULL), then the %directive is ignored. As a result, %name-prefix,
+ for instance, will not be honored. */
+
+char *spec_outfile = NULL; /* for -o. */
+char *spec_file_prefix = NULL; /* for -b. */
+const char *spec_name_prefix = NULL; /* for -p. */
+char *spec_verbose_file = NULL; /* for --verbose. */
+char *spec_graph_file = NULL; /* for -g. */
+char *spec_defines_file = NULL; /* for --defines. */
+char *parser_file_name = NULL;
+
+char *infile = NULL;
+char *attrsfile = NULL;
+
+static char *full_base_name = NULL;
+
+/* Prefix used to generate output file names. */
+char *short_base_name = NULL;
+
+/* Infix used to generate output file names (i.e., `.tab', or `_tab',
+ or `'). */
+char *output_infix = NULL;
+
+/* C source file extension (the parser source). */
+const char *src_extension = NULL;
+/* Header file extension (if option ``-d'' is specified). */
+const char *header_extension = NULL;