Have Bison grammars parsed by a Bison grammar.

* src/reader.c, src/reader.h (prologue_augment): New.
* src/reader.c (copy_definition): Remove.
* src/reader.h, src/reader.c (gram_start_symbol_set, prologue_augment)
(grammar_symbol_append, grammar_rule_begin, grammar_midrule_action)
(grammar_current_rule_prec_set, grammar_current_rule_check)
(grammar_current_rule_symbol_append)
(grammar_current_rule_action_append): Export.
* src/parse-gram.y (symbol_list_new, symbol_list_symbol_append_
(symbol_list_action_append): Remove.
Hook the routines from reader.
* src/scan-gram.l: In INITIAL, characters and strings are tokens.
* src/system.h (ATTRIBUTE_NORETURN, ATTRIBUTE_UNUSED): Now.
* src/reader.c (read_declarations): Remove, unused.
* src/parse-gram.y: Handle the epilogue.
* src/reader.h, src/reader.c (gram_start_symbol_set): Rename as...
(grammar_start_symbol_set): this.
* src/scan-gram.l: Be sure to ``use'' yycontrol to keep GCC quiet.
* src/reader.c (readgram): Remove, unused.
(reader): Adjust to insert eoftoken and axiom where appropriate.
* src/reader.c (copy_dollar): Replace with...
* src/scan-gram.h (handle_dollar): this.
* src/parse-gram.y: Remove `%thong'.
* src/reader.c (copy_at): Replace with...
* src/scan-gram.h (handle_at): this.
* src/complain.h, src/complain.c (warn_at, complain_at, fatal_at):
New.
* src/scan-gram.l (YY_LINES): Keep lineno synchronized for the
time being.
* src/reader.h, src/reader.c (grammar_rule_end): New.
* src/parse.y (current_type, current_class): New.
Implement `%nterm', `%token' support.
Merge `%term' into `%token'.
(string_as_id): New.
* src/symtab.h, src/symtab.c (symbol_make_alias): Don't pass the
type name.
* src/parse-gram.y: Be sure to handle properly the beginning of
rules.
* src/parse-gram.y: Handle %type.
* src/reader.c (grammar_rule_end): Call grammar_current_rule_check.
* src/parse-gram.y: More directives support.
* src/options.c: No longer handle source directives.
* src/parse-gram.y: Fix %output.
* src/parse-gram.y: Handle %union.
Use the prologue locations.
* src/reader.c (parse_union_decl): Remove.
* src/reader.h, src/reader.c (epilogue_set): New.
* src/parse-gram.y: Use it.
* data/bison.simple, data/bison.c++: b4_stype is now either not
defined, then default to int, or to the contents of %union,
without `union' itself.
Adjust.
* src/muscle_tab.c (muscle_init): Don't predefine `stype'.
* src/output.c (actions_output): Don't output braces, as they are
already handled by the scanner.
* src/scan-gram.l (SC_CHARACTER): Set the user_token_number of
characters to themselves.
* tests/reduce.at (Reduced Automaton): End the grammars with %% so
that the epilogue has a proper #line.
* src/parse-gram.y: Handle precedence/associativity.
* src/symtab.c (symbol_precedence_set): Requires the symbol to be
a terminal.
* src/scan-gram.l (SC_BRACED_CODE): Catch strings and characters.
* tests/calc.at: Do not use `%token "foo"' as it makes not sense
at all to define terminals that cannot be emitted.
* src/scan-gram.l: Escape M4 characters.
* src/scan-gram.l: Working properly with escapes in user
strings/characters.
* tests/torture.at (AT_DATA_TRIANGULAR_GRAMMAR)
(AT_DATA_HORIZONTAL_GRAMMAR): Respect the `%token ID NUM STRING'
grammar.
Use more modest sizes, as for the time being the parser does not
release memory, and therefore the process swallows a huge amount
of memory.
* tests/torture.at (AT_DATA_LOOKAHEADS_GRAMMAR): Adjust to the
stricter %token grammar.
* src/symtab.h (associativity): Add `undef_assoc'.
(symbol_precedence_set): Do nothing when passed an undef_assoc.
* src/symtab.c (symbol_check_alias_consistence): Adjust.
* tests/regression.at (Invalid %directive): Remove, as it is now
meaningless.
(Invalid inputs): Adjust to the new error messages.
(Token definitions): The new grammar doesn't allow too many
eccentricities.
* src/lex.h, src/lex.c: Remove.
* src/reader.c (lastprec, skip_to_char, read_signed_integer)
(copy_character, copy_string2, copy_string, copy_identifier)
(copy_comment, parse_token_decl, parse_type_decl, parse_assoc_decl)
(parse_muscle_decl, parse_dquoted_param, parse_skel_decl)
(parse_action): Remove.
* po/POTFILES.in: Adjust.

src/complain.c

@@ -114,6 +114,56 @@ unsigned int complain_message_count;
 | Report a warning, and proceed.  |
 `--------------------------------*/
 
+void
+#if defined VA_START && defined __STDC__
+warn_at (int location, const char *message, ...)
+#else
+warn_at (location, message, va_alist)
+  int location
+  char *message;
+  va_dcl
+#endif
+{
+#ifdef VA_START
+  va_list args;
+#endif
+
+  if (error_one_per_line)
+    {
+      static const char *old_infile;
+      static int old_lineno;
+
+      if (old_lineno == location &&
+	  (infile == old_infile || !strcmp (old_infile, infile)))
+	/* Simply return and print nothing.  */
+	return;
+
+      old_infile = infile;
+      old_lineno = location;
+    }
+
+  fflush (stdout);
+  if (infile != NULL)
+    fprintf (stderr, "%s:%d: ", infile, location);
+  else
+    fprintf (stderr, "%s:", program_name);
+
+  fputs (_("warning: "), stderr);
+
+#ifdef VA_START
+  VA_START (args, message);
+  vfprintf (stderr, message, args);
+  va_end (args);
+#else
+  fprintf (stderr, message, a1, a2, a3, a4, a5, a6, a7, a8);
+#endif
+
+  ++warn_message_count;
+  putc ('\n', stderr);
+  fflush (stderr);
+}
+
+
 void
 #if defined VA_START && defined __STDC__
 warn (const char *message, ...)
@@ -166,6 +216,54 @@ warn (message, va_alist)
 | An error has occurred, but we can proceed, and die later.  |
 `-----------------------------------------------------------*/
 
+void
+#if defined VA_START && defined __STDC__
+complain_at (int location, const char *message, ...)
+#else
+complain_at (location, message, va_alist)
+  int location;
+  char *message;
+  va_dcl
+#endif
+{
+#ifdef VA_START
+  va_list args;
+#endif
+
+  if (error_one_per_line)
+    {
+      static const char *old_infile;
+      static int old_lineno;
+
+      if (old_lineno == location &&
+	  (infile == old_infile || !strcmp (old_infile, infile)))
+	/* Simply return and print nothing.  */
+	return;
+
+      old_infile = infile;
+      old_lineno = location;
+    }
+
+  fflush (stdout);
+  if (infile != NULL)
+    fprintf (stderr, "%s:%d: ", infile, location);
+  else
+    fprintf (stderr, "%s:", program_name);
+
+#ifdef VA_START
+  VA_START (args, message);
+  vfprintf (stderr, message, args);
+  va_end (args);
+#else
+  fprintf (stderr, message, a1, a2, a3, a4, a5, a6, a7, a8);
+#endif
+
+  ++complain_message_count;
+  putc ('\n', stderr);
+  fflush (stderr);
+}
+
+
 void
 #if defined VA_START && defined __STDC__
 complain (const char *message, ...)
@@ -216,6 +314,40 @@ complain (message, va_alist)
 | A severe error has occurred, we cannot proceed.  |
 `-------------------------------------------------*/
 
+void
+#if defined VA_START && defined __STDC__
+fatal_at (int location, const char *message, ...)
+#else
+fatal (location, message, va_alist)
+  int location;
+  char *message;
+  va_dcl
+#endif
+{
+#ifdef VA_START
+  va_list args;
+#endif
+
+  fflush (stdout);
+  if (infile != NULL)
+    fprintf (stderr, "%s:%d: ", infile, location);
+  else
+    fprintf (stderr, "%s:", program_name);
+
+  fputs (_("fatal error: "), stderr);
+
+#ifdef VA_START
+  VA_START (args, message);
+  vfprintf (stderr, message, args);
+  va_end (args);
+#else
+  fprintf (stderr, message, a1, a2, a3, a4, a5, a6, a7, a8);
+#endif
+  putc ('\n', stderr);
+  fflush (stderr);
+  exit (1);
+}
+
 void
 #if defined VA_START && defined __STDC__
 fatal (const char *message, ...)