(_AT_TEST_GLR_CXXTYPES): Do not include <assert.h>.

[bison.git] / src / reader.c

diff --git a/src/reader.c b/src/reader.c
index 822b9fe48d8aef46994b73bf73ba1090a8ecdb6a..5ed02b2e4971d0f9ed4a81517856b55e4ef514a4 100644 (file)
--- a/src/reader.c
+++ b/src/reader.c
@@ -1,4 +1,4 @@
-/* Input parser for bison
+/* Input parser for Bison

    Copyright (C) 1984, 1986, 1989, 1992, 1998, 2000, 2001, 2002
    Free Software Foundation, Inc.
 
    Copyright (C) 1984, 1986, 1989, 1992, 1998, 2000, 2001, 2002
    Free Software Foundation, Inc.
 


@@ -22,11 +22,10 @@
 
 #include "system.h"
 #include "quotearg.h"
 
 #include "system.h"
 #include "quotearg.h"

-#include "quote.h"

 #include "getargs.h"
 #include "files.h"
 #include "symtab.h"
 #include "getargs.h"
 #include "files.h"
 #include "symtab.h"

-#include "options.h"
+#include "symlist.h"

 #include "gram.h"
 #include "complain.h"
 #include "output.h"
 #include "gram.h"
 #include "complain.h"
 #include "output.h"


@@ -34,75 +33,27 @@
 #include "conflicts.h"
 #include "muscle_tab.h"
 
 #include "conflicts.h"
 #include "muscle_tab.h"
 

-int lineno;
-static symbol_list *grammar = NULL;
+static symbol_list_t *grammar = NULL;

 static int start_flag = 0;
 static int start_flag = 0;

+merger_list *merge_functions;

 
 /* Nonzero if %union has been seen.  */
 int typed = 0;
 
 /* Nonzero if %union has been seen.  */
 int typed = 0;

-
-static symbol_list *
-symbol_list_new (symbol_t *sym)
-{
-  symbol_list *res = XMALLOC (symbol_list, 1);
-  res->next = NULL;
-  res->sym = sym;
-  res->line = lineno;
-  res->action = NULL;
-  res->action_line = 0;
-  res->ruleprec = NULL;
-  return res;
-}
-

 \f
 \f

-/*--------------------------------------------------------------.
-| Get the data type (alternative in the union) of the value for |
-| symbol N in rule RULE.                                        |
-`--------------------------------------------------------------*/
-
-char *
-get_type_name (int n, symbol_list *rule)
-{
-  int i;
-  symbol_list *rp;
-
-  if (n < 0)
-    {
-      complain (_("invalid $ value"));
-      return NULL;
-    }
-
-  rp = rule;
-  i = 0;
-
-  while (i < n)
-    {
-      rp = rp->next;
-      if (rp == NULL || rp->sym == NULL)
-       {
-         complain (_("invalid $ value"));
-         return NULL;
-       }
-      ++i;
-    }
-
-  return rp->sym->type_name;
-}
-
-

 /*-----------------------.
 | Set the start symbol.  |
 `-----------------------*/
 
 void
 /*-----------------------.
 | Set the start symbol.  |
 `-----------------------*/
 
 void

-grammar_start_symbol_set (symbol_t *s)
+grammar_start_symbol_set (symbol_t *s, location_t l)

 {
   if (start_flag)
 {
   if (start_flag)

-    complain (_("multiple %s declarations"), "%start");
+    complain_at (l, _("multiple %s declarations"), "%start");

   else
     {
       start_flag = 1;
       startsymbol = s;
   else
     {
       start_flag = 1;
       startsymbol = s;

+      startsymbol_location = l;

     }
 }
 
     }
 }
 


@@ -113,17 +64,15 @@ grammar_start_symbol_set (symbol_t *s)
 `----------------------------------------------------------------*/
 
 void
 `----------------------------------------------------------------*/
 
 void

-prologue_augment (const char *prologue, int location)
+prologue_augment (const char *prologue, location_t location)

 {
   struct obstack *oout =
     !typed ? &pre_prologue_obstack : &post_prologue_obstack;
 
 {
   struct obstack *oout =
     !typed ? &pre_prologue_obstack : &post_prologue_obstack;
 

-  if (!no_lines_flag)
-    {
-      obstack_fgrow2 (oout, muscle_find ("linef"),
-                     location, quotearg_style (c_quoting_style,
-                                               muscle_find ("filename")));
-    }
+  obstack_fgrow1 (oout, "]b4_syncline([[%d]], [[",
+                 location.first_line);
+  MUSCLE_OBSTACK_SGROW (oout, quotearg_style (c_quoting_style, location.file));
+  obstack_sgrow (oout, "]])[\n");

   obstack_sgrow (oout, prologue);
 }
 
   obstack_sgrow (oout, prologue);
 }
 


@@ -135,48 +84,83 @@ prologue_augment (const char *prologue, int location)
 `----------------------*/
 
 void
 `----------------------*/
 
 void

-epilogue_set (const char *epilogue, int location)
+epilogue_augment (const char *epilogue, location_t location)

 {
 {

-  struct obstack el_obstack;
-  obstack_init (&el_obstack);
-
-  if (!no_lines_flag)
-    {
-      obstack_fgrow2 (&el_obstack, muscle_find ("linef"),
-                     location, quotearg_style (c_quoting_style,
-                                               muscle_find ("filename")));
-    }
-  obstack_sgrow (&el_obstack, epilogue);
-  obstack_1grow (&el_obstack, 0);
-  muscle_insert ("epilogue", obstack_finish (&el_obstack));
+  char *extension = NULL;
+  obstack_fgrow1 (&muscle_obstack, "]b4_syncline([[%d]], [[",
+                 location.first_line);
+  MUSCLE_OBSTACK_SGROW (&muscle_obstack,
+                       quotearg_style (c_quoting_style, location.file));
+  obstack_sgrow (&muscle_obstack, "]])[\n");
+  obstack_sgrow (&muscle_obstack, epilogue);
+  obstack_1grow (&muscle_obstack, 0);
+  extension = obstack_finish (&muscle_obstack);
+  muscle_grow ("epilogue", extension, "");
+  obstack_free (&muscle_obstack, extension);

 }
 
 
 \f
 
 /*-------------------------------------------------------------------.
 }
 
 
 \f
 
 /*-------------------------------------------------------------------.

-| Generate a dummy symbol, a nonterminal, whose name cannot conflict |
-| with the user's names.                                             |
+| Return the merger index for a merging function named NAME, whose   |
+| arguments have type TYPE.  Records the function, if new, in        |
+| MERGER_LIST.                                                      |

 `-------------------------------------------------------------------*/
 
 `-------------------------------------------------------------------*/
 

-static symbol_t *
-gensym (void)
+static int
+get_merge_function (struniq_t name, struniq_t type, location_t loc)

 {
 {

-  /* Incremented for each generated symbol */
-  static int gensym_count = 0;
-  static char buf[256];
+  merger_list *syms;
+  merger_list head;
+  int n;
+
+  if (! glr_parser)
+    return 0;

 
 

-  symbol_t *sym;
+  if (type == NULL)
+    type = struniq_new ("");

 
 

-  sprintf (buf, "@%d", ++gensym_count);
-  sym = getsym (buf);
-  sym->class = nterm_sym;
-  sym->number = nvars++;
-  return sym;
+  head.next = merge_functions;
+  for (syms = &head, n = 1; syms->next != NULL; syms = syms->next, n += 1)
+    if (STRUNIQ_EQ (name, syms->next->name))
+      break;
+  if (syms->next == NULL)
+    {
+      syms->next = XMALLOC (merger_list, 1);
+      syms->next->name = struniq_new (name);
+      syms->next->type = struniq_new (type);
+      syms->next->next = NULL;
+      merge_functions = head.next;
+    }
+  else if (!STRUNIQ_EQ (type, syms->next->type))
+    warn_at (loc, _("result type clash on merge function %s: <%s> != <%s>"),
+            name, type, syms->next->type);
+  return n;

 }
 }

+
+/*--------------------------------------.
+| Free all merge-function definitions. |
+`--------------------------------------*/
+
+void
+free_merger_functions (void)
+{
+  merger_list *L0;
+  if (! glr_parser)
+    return;
+  L0 = merge_functions;
+  while (L0 != NULL)
+    {
+      merger_list *L1 = L0->next;
+      free (L0);
+      L0 = L1;
+    }
+}
+

 \f
 /*-------------------------------------------------------------------.
 \f
 /*-------------------------------------------------------------------.

-| Parse the input grammar into a one symbol_list structure.  Each    |
+| Parse the input grammar into a one symbol_list_t structure.  Each  |

 | rule is represented by a sequence of symbols: the left hand side   |
 | followed by the contents of the right hand side, followed by a     |
 | null pointer instead of a symbol to terminate the rule.  The next  |
 | rule is represented by a sequence of symbols: the left hand side   |
 | followed by the contents of the right hand side, followed by a     |
 | null pointer instead of a symbol to terminate the rule.  The next  |


@@ -194,13 +178,13 @@ gensym (void)
 `-------------------------------------------------------------------*/
 
 /* The (currently) last symbol of GRAMMAR. */
 `-------------------------------------------------------------------*/
 
 /* The (currently) last symbol of GRAMMAR. */

-symbol_list *grammar_end = NULL;
+symbol_list_t *grammar_end = NULL;

 
 /* Append S to the GRAMMAR. */
 void
 
 /* Append S to the GRAMMAR. */
 void

-grammar_symbol_append (symbol_t *s)
+grammar_symbol_append (symbol_t *symbol, location_t location)

 {
 {

-  symbol_list *p = symbol_list_new (s);
+  symbol_list_t *p = symbol_list_new (symbol, location);

 
   if (grammar_end)
     grammar_end->next = p;
 
   if (grammar_end)
     grammar_end->next = p;


@@ -210,20 +194,24 @@ grammar_symbol_append (symbol_t *s)
   grammar_end = p;
 }
 
   grammar_end = p;
 }
 

-/* The rule currently being defined, and the previous rule.  Point to
-   the first symbol of each list: their lhs.  */
-symbol_list *current_rule = NULL;
-symbol_list *previous_rule = NULL;
+/* The rule currently being defined, and the previous rule.
+   CURRENT_RULE points to the first LHS of the current rule, while
+   PREVIOUS_RULE_END points to the *end* of the previous rule (NULL).  */
+symbol_list_t *current_rule = NULL;
+symbol_list_t *previous_rule_end = NULL;

 
 
 
 

-/* Create a new rule for LHS in to the GRAMMAR. */
+/*----------------------------------------------.
+| Create a new rule for LHS in to the GRAMMAR.  |
+`----------------------------------------------*/

 
 void
 
 void

-grammar_rule_begin (symbol_t *lhs)
+grammar_rule_begin (symbol_t *lhs, location_t location)

 {
   if (!start_flag)
     {
       startsymbol = lhs;
 {
   if (!start_flag)
     {
       startsymbol = lhs;

+      startsymbol_location = location;

       start_flag = 1;
     }
 
       start_flag = 1;
     }
 


@@ -231,8 +219,8 @@ grammar_rule_begin (symbol_t *lhs)
   ++nrules;
   ++nritems;
 
   ++nrules;
   ++nritems;
 

-  previous_rule = grammar_end;
-  grammar_symbol_append (lhs);
+  previous_rule_end = grammar_end;
+  grammar_symbol_append (lhs, location);

   current_rule = grammar_end;
 
   /* Mark the rule's lhs as a nonterminal if not already so.  */
   current_rule = grammar_end;
 
   /* Mark the rule's lhs as a nonterminal if not already so.  */


@@ -244,7 +232,7 @@ grammar_rule_begin (symbol_t *lhs)
       ++nvars;
     }
   else if (lhs->class == token_sym)
       ++nvars;
     }
   else if (lhs->class == token_sym)

-    complain (_("rule given for %s, which is a token"), lhs->tag);
+    complain_at (location, _("rule given for %s, which is a token"), lhs->tag);

 }
 
 /* Check that the last rule (CURRENT_RULE) is properly defined.  For
 }
 
 /* Check that the last rule (CURRENT_RULE) is properly defined.  For


@@ -254,47 +242,55 @@ static void
 grammar_current_rule_check (void)
 {
   symbol_t *lhs = current_rule->sym;
 grammar_current_rule_check (void)
 {
   symbol_t *lhs = current_rule->sym;

+  char const *lhs_type = lhs->type_name;

   symbol_t *first_rhs = current_rule->next->sym;
 
   /* If there is an action, then there is nothing we can do: the user
   symbol_t *first_rhs = current_rule->next->sym;
 
   /* If there is an action, then there is nothing we can do: the user

-     is allowed to shoot in her foot.  */
+     is allowed to shoot herself in the foot.  */

   if (current_rule->action)
     return;
 
   if (current_rule->action)
     return;
 

-  /* If $$ is being set in default way, report if any type mismatch.
-     */
+  /* Don't worry about the default action if $$ is untyped, since $$'s
+     value can't be used.  */
+  if (! lhs_type)
+    return;
+
+  /* If $$ is being set in default way, report if any type mismatch.  */

   if (first_rhs)
     {
   if (first_rhs)
     {

-      const char *lhs_type = lhs->type_name       ? lhs->type_name       : "";

       const char *rhs_type = first_rhs->type_name ? first_rhs->type_name : "";
       const char *rhs_type = first_rhs->type_name ? first_rhs->type_name : "";

-      if (strcmp (lhs_type, rhs_type))
-       complain (_("type clash (`%s' `%s') on default action"),
-                 lhs_type, rhs_type);
+      if (!STRUNIQ_EQ (lhs_type, rhs_type))
+       complain_at (current_rule->location,
+                    _("type clash on default action: <%s> != <%s>"),
+                    lhs_type, rhs_type);

     }
   /* Warn if there is no default for $$ but we need one.  */
   else
     }
   /* Warn if there is no default for $$ but we need one.  */
   else

-    {
-      if (lhs->type_name)
-       complain (_("empty rule for typed nonterminal, and no action"));
-    }
+    complain_at (current_rule->location,
+                _("empty rule for typed nonterminal, and no action"));

 }
 
 
 }
 
 

-/* End the currently being grown rule. */
+/*-------------------------------------.
+| End the currently being grown rule.  |
+`-------------------------------------*/

 
 void
 
 void

-grammar_rule_end (void)
+grammar_rule_end (location_t location)

 {
   /* Put an empty link in the list to mark the end of this rule  */
 {
   /* Put an empty link in the list to mark the end of this rule  */

-  grammar_symbol_append (NULL);
+  grammar_symbol_append (NULL, grammar_end->location);
+  current_rule->location = location;

   grammar_current_rule_check ();
 }
 
 
   grammar_current_rule_check ();
 }
 
 

-/* The previous action turns out the be a mid-rule action.  Attach it
-   to the current rule, i.e., create a dummy symbol, attach it this
-   mid-rule action, and append this dummy nonterminal to the current
-   rule.  */
+/*-------------------------------------------------------------------.
+| The previous action turns out the be a mid-rule action.  Attach it |
+| to the current rule, i.e., create a dummy symbol, attach it this   |
+| mid-rule action, and append this dummy nonterminal to the current  |
+| rule.                                                              |
+`-------------------------------------------------------------------*/

 
 void
 grammar_midrule_action (void)
 
 void
 grammar_midrule_action (void)


@@ -303,70 +299,99 @@ grammar_midrule_action (void)
      give the new rule this number by inserting the new rule before
      it.  */
 
      give the new rule this number by inserting the new rule before
      it.  */
 

-  /* Make a dummy nonterminal, a gensym.  */
-  symbol_t *sdummy = gensym ();
-  symbol_list *midrule_action = symbol_list_new (sdummy);
+  /* Make a DUMMY nonterminal, whose location is that of the midrule
+     action.  Create the MIDRULE.  */
+  location_t dummy_location = current_rule->action_location;
+  symbol_t *dummy = dummy_symbol_get (dummy_location);
+  symbol_list_t *midrule = symbol_list_new (dummy, dummy_location);

 
   /* Make a new rule, whose body is empty, before the current one, so
      that the action just read can belong to it.  */
   ++nrules;
   ++nritems;
 
   /* Make a new rule, whose body is empty, before the current one, so
      that the action just read can belong to it.  */
   ++nrules;
   ++nritems;

-  /* Attach its lineno to that of the host rule.  */
-  midrule_action->line = current_rule->line;
-  /* Move the action from the host rule to this one.  */
-  midrule_action->action = current_rule->action;
-  midrule_action->action_line = current_rule->action_line;
+  /* Attach its location and actions to that of the DUMMY.  */
+  midrule->location = dummy_location;
+  midrule->action = current_rule->action;
+  midrule->action_location = dummy_location;

   current_rule->action = NULL;
 
   current_rule->action = NULL;
 

-  if (previous_rule)
-    previous_rule->next = midrule_action;
+  if (previous_rule_end)
+    previous_rule_end->next = midrule;

   else
   else

-    grammar = midrule_action;
+    grammar = midrule;

 
 

-  /* End of the rule. */
-  previous_rule = symbol_list_new (NULL);
-  previous_rule->next = current_rule;
+  /* End the dummy's rule.  */
+  previous_rule_end = symbol_list_new (NULL, dummy_location);
+  previous_rule_end->next = current_rule;

 
 

-  midrule_action->next = previous_rule;
+  midrule->next = previous_rule_end;

 
 

-  /* Insert the dummy generated by that rule into this rule.  */
-  ++nritems;
-  grammar_symbol_append (sdummy);
+  /* Insert the dummy nonterminal replacing the midrule action into
+     the current rule.  */
+  grammar_current_rule_symbol_append (dummy, dummy_location);

 }
 
 /* Set the precedence symbol of the current rule to PRECSYM. */
 
 void
 }
 
 /* Set the precedence symbol of the current rule to PRECSYM. */
 
 void

-grammar_current_rule_prec_set (symbol_t *precsym)
+grammar_current_rule_prec_set (symbol_t *precsym, location_t location)

 {
   if (current_rule->ruleprec)
 {
   if (current_rule->ruleprec)

-    complain (_("two @prec's in a row"));
+    complain_at (location, _("only one %s allowed per rule"), "%prec");

   current_rule->ruleprec = precsym;
 }
 
   current_rule->ruleprec = precsym;
 }
 

+/* Attach dynamic precedence DPREC to the current rule. */
+
+void
+grammar_current_rule_dprec_set (int dprec, location_t location)
+{
+  if (! glr_parser)
+    warn_at (location, _("%s affects only GLR parsers"), "%dprec");
+  if (dprec <= 0)
+    complain_at (location,
+                _("%s must be followed by positive number"), "%dprec");
+  else if (current_rule->dprec != 0)
+    complain_at (location, _("only one %s allowed per rule"), "%dprec");
+  current_rule->dprec = dprec;
+}
+
+/* Attach a merge function NAME with argument type TYPE to current
+   rule. */
+
+void
+grammar_current_rule_merge_set (struniq_t name, location_t location)
+{
+  if (! glr_parser)
+    warn_at (location, _("%s affects only GLR parsers"), "%merge");
+  if (current_rule->merger != 0)
+    complain_at (location, _("only one %s allowed per rule"), "%merge");
+  current_rule->merger =
+    get_merge_function (name, current_rule->sym->type_name, location);
+}
+

 /* Attach a SYMBOL to the current rule.  If needed, move the previous
    action as a mid-rule action.  */
 
 void
 /* Attach a SYMBOL to the current rule.  If needed, move the previous
    action as a mid-rule action.  */
 
 void

-grammar_current_rule_symbol_append (symbol_t *symbol)
+grammar_current_rule_symbol_append (symbol_t *symbol, location_t location)

 {
   if (current_rule->action)
     grammar_midrule_action ();
   ++nritems;
 {
   if (current_rule->action)
     grammar_midrule_action ();
   ++nritems;

-  grammar_symbol_append (symbol);
+  grammar_symbol_append (symbol, location);

 }
 
 }
 

-

 /* Attach an ACTION to the current rule.  If needed, move the previous
    action as a mid-rule action.  */
 
 void
 /* Attach an ACTION to the current rule.  If needed, move the previous
    action as a mid-rule action.  */
 
 void

-grammar_current_rule_action_append (const char *action, int action_line)
+grammar_current_rule_action_append (const char *action, location_t location)

 {
   if (current_rule->action)
     grammar_midrule_action ();
   current_rule->action = action;
 {
   if (current_rule->action)
     grammar_midrule_action ();
   current_rule->action = action;

-  current_rule->action_line = action_line;
+  current_rule->action_location = location;

 }
 
 \f
 }
 
 \f


@@ -378,17 +403,13 @@ grammar_current_rule_action_append (const char *action, int action_line)
 static void
 packgram (void)
 {
 static void
 packgram (void)
 {

-  unsigned int itemno;
-  int ruleno;
-  symbol_list *p;
+  unsigned int itemno = 0;
+  rule_number_t ruleno = 0;
+  symbol_list_t *p = grammar;

 
   ritem = XCALLOC (item_number_t, nritems);
 
   ritem = XCALLOC (item_number_t, nritems);

-  rules = XCALLOC (rule_t, nrules) - 1;
+  rules = XCALLOC (rule_t, nrules);

 
 

-  itemno = 0;
-  ruleno = 1;
-
-  p = grammar;

   while (p)
     {
       symbol_t *ruleprec = p->ruleprec;
   while (p)
     {
       symbol_t *ruleprec = p->ruleprec;


@@ -396,10 +417,12 @@ packgram (void)
       rules[ruleno].number = ruleno;
       rules[ruleno].lhs = p->sym;
       rules[ruleno].rhs = ritem + itemno;
       rules[ruleno].number = ruleno;
       rules[ruleno].lhs = p->sym;
       rules[ruleno].rhs = ritem + itemno;

-      rules[ruleno].line = p->line;
-      rules[ruleno].useful = TRUE;
+      rules[ruleno].location = p->location;
+      rules[ruleno].useful = true;

       rules[ruleno].action = p->action;
       rules[ruleno].action = p->action;

-      rules[ruleno].action_line = p->action_line;
+      rules[ruleno].action_location = p->action_location;
+      rules[ruleno].dprec = p->dprec;
+      rules[ruleno].merger = p->merger;

 
       p = p->next;
       while (p && p->sym)
 
       p = p->next;
       while (p && p->sym)


@@ -422,16 +445,17 @@ packgram (void)
          rules[ruleno].precsym = ruleprec;
          rules[ruleno].prec = ruleprec;
        }
          rules[ruleno].precsym = ruleprec;
          rules[ruleno].prec = ruleprec;
        }

-      ritem[itemno++] = -ruleno;
+      ritem[itemno++] = rule_number_as_item_number (ruleno);

       ++ruleno;
 
       if (p)
        p = p->next;
     }
 
       ++ruleno;
 
       if (p)
        p = p->next;
     }
 

-  assert (itemno == nritems);
+  if (itemno != nritems)
+    abort ();

 
 

-  if (trace_flag)
+  if (trace_flag & trace_sets)

     ritem_print (stderr);
 }
 \f
     ritem_print (stderr);
 }
 \f


@@ -446,44 +470,43 @@ void
 reader (void)
 {
   gram_control_t gram_control;
 reader (void)
 {
   gram_control_t gram_control;

-  lineno = 1;
-
-  /* Initialize the muscle obstack.  */
-  obstack_init (&muscle_obstack);

 
   /* Initialize the symbol table.  */
   symbols_new ();
 
 
   /* Initialize the symbol table.  */
   symbols_new ();
 

-  /* Construct the axiom symbol. */
-  axiom = getsym ("$axiom");
-  axiom->class = nterm_sym;
-  axiom->number = nvars++;
+  /* Construct the accept symbol. */
+  accept = symbol_get ("$accept", empty_location);
+  accept->class = nterm_sym;
+  accept->number = nvars++;

 
   /* Construct the error token */
 
   /* Construct the error token */

-  errtoken = getsym ("error");
+  errtoken = symbol_get ("error", empty_location);

   errtoken->class = token_sym;
   errtoken->number = ntokens++;
 
   /* Construct a token that represents all undefined literal tokens.
      It is always token number 2.  */
   errtoken->class = token_sym;
   errtoken->number = ntokens++;
 
   /* Construct a token that represents all undefined literal tokens.
      It is always token number 2.  */

-  undeftoken = getsym ("$undefined.");
+  undeftoken = symbol_get ("$undefined", empty_location);

   undeftoken->class = token_sym;
   undeftoken->number = ntokens++;
 
   /* Initialize the obstacks. */
   undeftoken->class = token_sym;
   undeftoken->number = ntokens++;
 
   /* Initialize the obstacks. */

-  obstack_init (&action_obstack);
-  obstack_init (&output_obstack);

   obstack_init (&pre_prologue_obstack);
   obstack_init (&post_prologue_obstack);
 
   obstack_init (&pre_prologue_obstack);
   obstack_init (&post_prologue_obstack);
 

-  finput = xfopen (infile, "r");
+  finput = xfopen (grammar_file, "r");

   gram_in = finput;
 
   gram_in = finput;
 

-  gram_debug = !!getenv ("parse");
-  gram__flex_debug = !!getenv ("scan");
+  gram__flex_debug = trace_flag & trace_scan;
+  gram_debug = trace_flag & trace_parse;

   scanner_initialize ();
   gram_parse (&gram_control);
 
   scanner_initialize ();
   gram_parse (&gram_control);
 

+  /* If something went wrong during the parsing, don't try to
+     continue.  */
+  if (complaint_issued)
+    return;
+

   /* Grammar has been read.  Do some checking */
   if (nrules == 0)
     fatal (_("no rules in the input grammar"));
   /* Grammar has been read.  Do some checking */
   if (nrules == 0)
     fatal (_("no rules in the input grammar"));


@@ -491,37 +514,34 @@ reader (void)
   /* Report any undefined symbols and consider them nonterminals.  */
   symbols_check_defined ();
 
   /* Report any undefined symbols and consider them nonterminals.  */
   symbols_check_defined ();
 

-  /* If the user did not define her EOFTOKEN, do it now. */
-  if (!eoftoken)
+  /* If the user did not define her ENDTOKEN, do it now. */
+  if (!endtoken)

     {
     {

-      eoftoken = getsym ("$");
-      eoftoken->class = token_sym;
-      eoftoken->number = 0;
+      endtoken = symbol_get ("$end", empty_location);
+      endtoken->class = token_sym;
+      endtoken->number = 0;

       /* Value specified by POSIX.  */
       /* Value specified by POSIX.  */

-      eoftoken->user_token_number = 0;
+      endtoken->user_token_number = 0;

     }
 
   /* Insert the initial rule, which line is that of the first rule
      (not that of the start symbol):
 
     }
 
   /* Insert the initial rule, which line is that of the first rule
      (not that of the start symbol):
 

-     axiom: %start EOF.  */
+     accept: %start EOF.  */

   {
   {

-    symbol_list *p = symbol_list_new (axiom);
-    p->line = grammar->line;
-    p->next = symbol_list_new (startsymbol);
-    p->next->next = symbol_list_new (eoftoken);
-    p->next->next->next = symbol_list_new (NULL);
+    symbol_list_t *p = symbol_list_new (accept, empty_location);
+    p->location = grammar->location;
+    p->next = symbol_list_new (startsymbol, empty_location);
+    p->next->next = symbol_list_new (endtoken, empty_location);
+    p->next->next->next = symbol_list_new (NULL, empty_location);

     p->next->next->next->next = grammar;
     nrules += 1;
     nritems += 3;
     grammar = p;
   }
 
     p->next->next->next->next = grammar;
     nrules += 1;
     nritems += 3;
     grammar = p;
   }
 

-  if (nsyms > SHRT_MAX)
-    fatal (_("too many symbols (tokens plus nonterminals); maximum %d"),
-          SHRT_MAX);
-
-  assert (nsyms == ntokens + nvars);
+  if (! (nsyms <= SYMBOL_NUMBER_MAX && nsyms == ntokens + nvars))
+    abort ();

 
   xfclose (finput);
 
 
   xfclose (finput);
 


@@ -532,6 +552,6 @@ reader (void)
   /* Convert the grammar into the format described in gram.h.  */
   packgram ();
 
   /* Convert the grammar into the format described in gram.h.  */
   packgram ();
 

-  /* The grammar as a symbol_list is no longer needed. */
-  LIST_FREE (symbol_list, grammar);
+  /* The grammar as a symbol_list_t is no longer needed. */
+  LIST_FREE (symbol_list_t, grammar);

 }
 }