* tests/input.at (Invalid $n, Invalid @n): Add the ending `;'.

[bison.git] / src / reader.c

diff --git a/src/reader.c b/src/reader.c
index c5f3b11ec4e0a83b4d313ad5f8c79f0b205983ff..ce9c34f070a523eaae3808aeacef597868838715 100644 (file)
--- a/src/reader.c
+++ b/src/reader.c
@@ -1,5 +1,5 @@
 /* Input parser for bison
 /* Input parser for bison

-   Copyright 1984, 1986, 1989, 1992, 1998, 2000, 2001
+   Copyright (C) 1984, 1986, 1989, 1992, 1998, 2000, 2001, 2002

    Free Software Foundation, Inc.
 
    This file is part of Bison, the GNU Compiler Compiler.
    Free Software Foundation, Inc.
 
    This file is part of Bison, the GNU Compiler Compiler.


@@ -52,8 +52,6 @@ typedef struct symbol_list
 } symbol_list;
 
 int lineno;
 } symbol_list;
 
 int lineno;

-char **tags;
-short *user_toknums;

 static symbol_list *grammar;
 static int start_flag;
 static bucket *startval;
 static symbol_list *grammar;
 static int start_flag;
 static bucket *startval;


@@ -71,6 +69,7 @@ static int lastprec;
 static bucket *errtoken = NULL;
 static bucket *undeftoken = NULL;
 static bucket *eoftoken = NULL;
 static bucket *errtoken = NULL;
 static bucket *undeftoken = NULL;
 static bucket *eoftoken = NULL;

+static bucket *axiom = NULL;

 
 static symbol_list *
 symbol_list_new (bucket *sym)
 
 static symbol_list *
 symbol_list_new (bucket *sym)


@@ -1155,10 +1154,7 @@ parse_braces (symbol_list *rule, int stack_offset)
 
       /* Above loop exits when C is '}'.  */
       if (--count)
 
       /* Above loop exits when C is '}'.  */
       if (--count)

-       {
-         obstack_1grow (&action_obstack, c);
-         c = getc (finput);
-       }
+       obstack_1grow (&action_obstack, c);

     }
 
   obstack_1grow (&action_obstack, '\0');
     }
 
   obstack_1grow (&action_obstack, '\0');


@@ -1330,7 +1326,10 @@ readgram (void)
                unlex (t1);
                symval = ssave;
                if (t1 == tok_colon)
                unlex (t1);
                symval = ssave;
                if (t1 == tok_colon)

-                 break;
+                 {
+                   complain (_("previous rule lacks an ending `;'"));
+                   break;
+                 }

 
                if (!first_rhs) /* JF */
                  first_rhs = symval;
 
                if (!first_rhs) /* JF */
                  first_rhs = symval;


@@ -1358,6 +1357,11 @@ readgram (void)
                p = symbol_list_new (sdummy);
                /* Attach its lineno to that of the host rule. */
                p->line = crule->line;
                p = symbol_list_new (sdummy);
                /* Attach its lineno to that of the host rule. */
                p->line = crule->line;

+               /* Move the action from the host rule to this one. */
+               p->action = crule->action;
+               p->action_line = crule->action_line;
+               crule->action = NULL;
+

                if (crule1)
                  crule1->next = p;
                else
                if (crule1)
                  crule1->next = p;
                else


@@ -1441,6 +1445,8 @@ readgram (void)
        /* Warn if there is no default for $$ but we need one.  */
        else if (!xactions && !first_rhs && lhs->type_name != 0)
          complain (_("empty rule for typed nonterminal, and no action"));
        /* Warn if there is no default for $$ but we need one.  */
        else if (!xactions && !first_rhs && lhs->type_name != 0)
          complain (_("empty rule for typed nonterminal, and no action"));

+       if (t == tok_two_percents || t == tok_eof)
+         complain (_("previous rule lacks an ending `;'"));

        if (t == tok_semicolon)
          t = lex ();
       }
        if (t == tok_semicolon)
          t = lex ();
       }


@@ -1450,12 +1456,8 @@ readgram (void)
        t = lex ();
       }
 
        t = lex ();
       }
 

-

   /* grammar has been read.  Do some checking */
 
   /* grammar has been read.  Do some checking */
 

-  if (nsyms > MAXSHORT)
-    fatal (_("too many symbols (tokens plus nonterminals); maximum %d"),
-          MAXSHORT);

   if (nrules == 0)
     fatal (_("no rules in the input grammar"));
 
   if (nrules == 0)
     fatal (_("no rules in the input grammar"));
 


@@ -1471,6 +1473,25 @@ readgram (void)
        bp->value = nvars++;
       }
 
        bp->value = nvars++;
       }
 

+  /* Insert the initial rule, which line is that of the first rule
+     (not that of the start symbol):
+
+     axiom: %start EOF.  */
+  p = symbol_list_new (axiom);
+  p->line = grammar->line;
+  p->next = symbol_list_new (startval);
+  p->next->next = symbol_list_new (eoftoken);
+  p->next->next->next = symbol_list_new (NULL);
+  p->next->next->next->next = grammar;
+  nrules += 1;
+  nitems += 3;
+  grammar = p;
+  startval = axiom;
+
+  if (nsyms > MAXSHORT)
+    fatal (_("too many symbols (tokens plus nonterminals); maximum %d"),
+          MAXSHORT);
+

   ntokens = nsyms - nvars;
 }
 
   ntokens = nsyms - nvars;
 }
 


@@ -1533,18 +1554,17 @@ token_translations_init (void)
       /* A token which translation has already been set? */
       if (token_translations[bp->user_token_number] != 2)
        complain (_("tokens %s and %s both assigned number %d"),
       /* A token which translation has already been set? */
       if (token_translations[bp->user_token_number] != 2)
        complain (_("tokens %s and %s both assigned number %d"),

-                 tags[token_translations[bp->user_token_number]],
+                 symbols[token_translations[bp->user_token_number]]->tag,

                  bp->tag, bp->user_token_number);
       token_translations[bp->user_token_number] = bp->value;
     }
 }
 
 
                  bp->tag, bp->user_token_number);
       token_translations[bp->user_token_number] = bp->value;
     }
 }
 
 

-/*------------------------------------------------------------------.
-| Assign symbol numbers, and write definition of token names into   |
-| FDEFINES.  Set up vectors TAGS and SPREC of names and precedences |
-| of symbols.                                                       |
-`------------------------------------------------------------------*/
+/*----------------------------------------------------------------.
+| Assign symbol numbers, and write definition of token names into |
+| FDEFINES.  Set up vectors SYMBOL_TABLE, TAGS of symbols.        |
+`----------------------------------------------------------------*/

 
 static void
 packsymbols (void)
 
 static void
 packsymbols (void)


@@ -1553,11 +1573,7 @@ packsymbols (void)
   int tokno = 1;
   int last_user_token_number;
 
   int tokno = 1;
   int last_user_token_number;
 

-  tags = XCALLOC (char *, nsyms + 1);
-  user_toknums = XCALLOC (short, nsyms + 1);
-
-  sprec = XCALLOC (short, nsyms);
-  sassoc = XCALLOC (short, nsyms);
+  symbols = XCALLOC (bucket *, nsyms);

 
   max_user_token_number = 256;
   last_user_token_number = 256;
 
   max_user_token_number = 256;
   last_user_token_number = 256;


@@ -1628,10 +1644,7 @@ packsymbols (void)
            max_user_token_number = bp->user_token_number;
        }
 
            max_user_token_number = bp->user_token_number;
        }
 

-      tags[bp->value] = bp->tag;
-      user_toknums[bp->value] = bp->user_token_number;
-      sprec[bp->value] = bp->prec;
-      sassoc[bp->value] = bp->assoc;
+      symbols[bp->value] = bp;

     }
 
   token_translations_init ();
     }
 
   token_translations_init ();


@@ -1647,56 +1660,6 @@ packsymbols (void)
 }
 
 
 }
 
 

-/*---------------------------------------------------------------.
-| Save the definition of token names in the `TOKENDEFS' muscle.  |
-`---------------------------------------------------------------*/
-
-static void
-symbols_save (void)
-{
-  struct obstack tokendefs;
-  bucket *bp;
-  obstack_init (&tokendefs);
-
-  for (bp = firstsymbol; bp; bp = bp->next)
-    {
-      char *symbol = bp->tag;                /* get symbol */
-
-      if (bp->value >= ntokens)
-       continue;
-      if (bp->user_token_number == SALIAS)
-       continue;
-      if ('\'' == *symbol)
-       continue;               /* skip literal character */
-      if (bp == errtoken)
-       continue;               /* skip error token */
-      if ('\"' == *symbol)
-       {
-         /* use literal string only if given a symbol with an alias */
-         if (bp->alias)
-           symbol = bp->alias->tag;
-         else
-           continue;
-       }
-
-      /* Don't #define nonliteral tokens whose names contain periods.  */
-      if (strchr (symbol, '.'))
-       continue;
-
-      obstack_fgrow2 (&tokendefs, "# define %s\t%d\n",
-                     symbol, bp->user_token_number);
-      if (semantic_parser)
-       /* FIXME: This is probably wrong, and should be just as
-          above. --akim.  */
-       obstack_fgrow2 (&tokendefs, "# define T%s\t%d\n", symbol, bp->value);
-    }
-
-  obstack_1grow (&tokendefs, 0);
-  muscle_insert ("tokendef", xstrdup (obstack_finish (&tokendefs)));
-  obstack_free (&tokendefs, NULL);
-}
-
-

 /*---------------------------------------------------------------.
 | Convert the rules into the representation using RRHS, RLHS and |
 | RITEMS.                                                        |
 /*---------------------------------------------------------------.
 | Convert the rules into the representation using RRHS, RLHS and |
 | RITEMS.                                                        |


@@ -1714,7 +1677,7 @@ packgram (void)
     fatal (_("too many items (max %d)"), MAXSHORT);
 
   ritem = XCALLOC (short, nitems + 1);
     fatal (_("too many items (max %d)"), MAXSHORT);
 
   ritem = XCALLOC (short, nitems + 1);

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

 
   itemno = 0;
   ruleno = 1;
 
   itemno = 0;
   ruleno = 1;


@@ -1723,14 +1686,14 @@ packgram (void)
   while (p)
     {
       bucket *ruleprec = p->ruleprec;
   while (p)
     {
       bucket *ruleprec = p->ruleprec;

-      rule_table[ruleno].lhs = p->sym->value;
-      rule_table[ruleno].rhs = itemno;
-      rule_table[ruleno].line = p->line;
-      rule_table[ruleno].useful = TRUE;
-      rule_table[ruleno].action = p->action;
-      rule_table[ruleno].action_line = p->action_line;
-      rule_table[ruleno].guard = p->guard;
-      rule_table[ruleno].guard_line = p->guard_line;
+      rules[ruleno].lhs = p->sym->value;
+      rules[ruleno].rhs = itemno;
+      rules[ruleno].line = p->line;
+      rules[ruleno].useful = TRUE;
+      rules[ruleno].action = p->action;
+      rules[ruleno].action_line = p->action_line;
+      rules[ruleno].guard = p->guard;
+      rules[ruleno].guard_line = p->guard_line;

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


@@ -1740,8 +1703,8 @@ packgram (void)
             of the last token in it.  */
          if (p->sym->class == token_sym)
            {
             of the last token in it.  */
          if (p->sym->class == token_sym)
            {

-             rule_table[ruleno].prec = p->sym->prec;
-             rule_table[ruleno].assoc = p->sym->assoc;
+             rules[ruleno].prec = p->sym->prec;
+             rules[ruleno].assoc = p->sym->assoc;

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


@@ -1751,9 +1714,9 @@ packgram (void)
          the specified symbol's precedence replaces the default.  */
       if (ruleprec)
        {
          the specified symbol's precedence replaces the default.  */
       if (ruleprec)
        {

-         rule_table[ruleno].prec = ruleprec->prec;
-         rule_table[ruleno].assoc = ruleprec->assoc;
-         rule_table[ruleno].precsym = ruleprec->value;
+         rules[ruleno].prec = ruleprec->prec;
+         rules[ruleno].assoc = ruleprec->assoc;
+         rules[ruleno].precsym = ruleprec->value;

        }
 
       ritem[itemno++] = -ruleno;
        }
 
       ritem[itemno++] = -ruleno;


@@ -1764,6 +1727,8 @@ packgram (void)
     }
 
   ritem[itemno] = 0;
     }
 
   ritem[itemno] = 0;

+  nritems = itemno;
+  assert (nritems == nitems);

 
   if (trace_flag)
     ritem_print (stderr);
 
   if (trace_flag)
     ritem_print (stderr);


@@ -1805,6 +1770,11 @@ reader (void)
   /* Initialize the symbol table.  */
   tabinit ();
 
   /* Initialize the symbol table.  */
   tabinit ();
 

+  /* Construct the axiom symbol. */
+  axiom = getsym ("$axiom");
+  axiom->class = nterm_sym;
+  axiom->value = nvars++;
+

   /* Construct the error token */
   errtoken = getsym ("error");
   errtoken->class = token_sym;
   /* Construct the error token */
   errtoken = getsym ("error");
   errtoken->class = token_sym;


@@ -1849,9 +1819,19 @@ reader (void)
   /* Assign the symbols their symbol numbers.  Write #defines for the
      token symbols into FDEFINES if requested.  */
   packsymbols ();
   /* Assign the symbols their symbol numbers.  Write #defines for the
      token symbols into FDEFINES if requested.  */
   packsymbols ();

-  /* Save them. */
-  symbols_save ();

 
   /* 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);
+}
+
+void
+grammar_free (void)
+{
+  XFREE (ritem);
+  free (rules + 1);
+  /* Free the symbol table data structure.  */
+  free_symtab ();

 }
 }