* doc/bison.texinfo (Stack Overflow): xref to Recursion.

[bison.git] / src / symtab.c

diff --git a/src/symtab.c b/src/symtab.c
index 1c45965e98a3a169b364470051315c77e7733361..7b3131205dc8f44851244b45c90da569e187ae38 100644 (file)
--- a/src/symtab.c
+++ b/src/symtab.c
@@ -20,6 +20,7 @@
 
 
 #include "system.h"
 
 
 #include "system.h"

+#include "quotearg.h"

 #include "hash.h"
 #include "complain.h"
 #include "symtab.h"
 #include "hash.h"
 #include "complain.h"
 #include "symtab.h"


@@ -31,59 +32,117 @@
 
 symbol_t *errtoken = NULL;
 symbol_t *undeftoken = NULL;
 
 symbol_t *errtoken = NULL;
 symbol_t *undeftoken = NULL;

-symbol_t *eoftoken = NULL;
-symbol_t *axiom = NULL;
+symbol_t *endtoken = NULL;
+symbol_t *accept = NULL;

 symbol_t *startsymbol = NULL;
 symbol_t *startsymbol = NULL;

+location_t startsymbol_location;

 
 /*---------------------------------.
 | Create a new symbol, named TAG.  |
 `---------------------------------*/
 
 static symbol_t *
 
 /*---------------------------------.
 | Create a new symbol, named TAG.  |
 `---------------------------------*/
 
 static symbol_t *

-symbol_new (const char *tag)
+symbol_new (const char *tag, location_t location)

 {
   symbol_t *res = XMALLOC (symbol_t, 1);
 
   res->tag = xstrdup (tag);
 {
   symbol_t *res = XMALLOC (symbol_t, 1);
 
   res->tag = xstrdup (tag);

+  res->location = location;
+

   res->type_name = NULL;
   res->type_name = NULL;

+  res->destructor = NULL;
+  res->printer = NULL;
+

   res->number = NUMBER_UNDEFINED;
   res->prec = 0;
   res->number = NUMBER_UNDEFINED;
   res->prec = 0;

-  res->assoc = right_assoc;
+  res->assoc = undef_assoc;

   res->user_token_number = USER_NUMBER_UNDEFINED;
   res->user_token_number = USER_NUMBER_UNDEFINED;

+

   res->alias = NULL;
   res->class = unknown_sym;
 
   nsyms++;
   res->alias = NULL;
   res->class = unknown_sym;
 
   nsyms++;

-

   return res;
 }
 
 
   return res;
 }
 
 

-/*-----------------------------------------.
-| Set the TYPE_NAME associated to SYMBOL.  |
-`-----------------------------------------*/
+/*------------------------------------------------------------------.
+| Set the TYPE_NAME associated to SYMBOL.  Does nothing if passed 0 |
+| as TYPE_NAME.                                                     |
+`------------------------------------------------------------------*/
+
+void
+symbol_type_set (symbol_t *symbol, char *type_name, location_t location)
+{
+  if (type_name)
+    {
+      if (symbol->type_name)
+       complain_at (location,
+                    _("type redeclaration for %s"), symbol->tag);
+      symbol->type_name = type_name;
+    }
+}
+
+
+/*-------------------------------------------------------------------.
+| Set the DESTRUCTOR associated to SYMBOL.  Do nothing if passed 0.  |
+`-------------------------------------------------------------------*/

 
 void
 
 void

-symbol_type_set (symbol_t *symbol, char *type_name)
+symbol_destructor_set (symbol_t *symbol, char *destructor, location_t location)

 {
 {

-  if (symbol->type_name)
-    complain (_("type redeclaration for %s"), symbol->tag);
-  symbol->type_name = type_name;
+  if (destructor)
+    {
+      if (symbol->destructor)
+       complain_at (location,
+                    _("%s redeclaration for %s"),
+                    "%destructor", symbol->tag);
+      symbol->destructor = destructor;
+      symbol->destructor_location = location;
+    }

 }
 
 
 }
 
 

-/*------------------------------------------.
-| Set the PRECEDENCE associated to SYMBOL.  |
-`------------------------------------------*/
+/*----------------------------------------------------------------.
+| Set the PRITNER associated to SYMBOL.  Do nothing if passed 0.  |
+`----------------------------------------------------------------*/
+
+void
+symbol_printer_set (symbol_t *symbol, char *printer, location_t location)
+{
+  if (printer)
+    {
+      if (symbol->printer)
+       complain_at (location,
+                    _("%s redeclaration for %s"),
+                    "%printer", symbol->tag);
+      symbol->printer = printer;
+      symbol->printer_location = location;
+    }
+}
+
+
+/*------------------------------------------------------------------.
+| Set the PRECEDENCE associated to SYMBOL.  Does nothing if invoked |
+| with UNDEF_ASSOC as ASSOC.                                        |
+`------------------------------------------------------------------*/

 
 void
 symbol_precedence_set (symbol_t *symbol,
 
 void
 symbol_precedence_set (symbol_t *symbol,

-                      int prec, associativity assoc)
+                      int prec, assoc_t assoc, location_t location)

 {
 {

-  if (symbol->prec != 0)
-    complain (_("redefining precedence of %s"), symbol->tag);
-  symbol->prec = prec;
-  symbol->assoc = assoc;
+  if (assoc != undef_assoc)
+    {
+      if (symbol->prec != 0)
+       complain_at (location,
+                    _("redefining precedence of %s"),
+                    symbol->tag);
+      symbol->prec = prec;
+      symbol->assoc = assoc;
+    }
+
+  /* Only terminals have a precedence. */
+  symbol_class_set (symbol, token_sym, location);

 }
 
 
 }
 
 


@@ -92,10 +151,10 @@ symbol_precedence_set (symbol_t *symbol,
 `-------------------------------------*/
 
 void
 `-------------------------------------*/
 
 void

-symbol_class_set (symbol_t *symbol, symbol_class class)
+symbol_class_set (symbol_t *symbol, symbol_class class, location_t location)

 {
   if (symbol->class != unknown_sym && symbol->class != class)
 {
   if (symbol->class != unknown_sym && symbol->class != class)

-    complain (_("symbol %s redefined"), symbol->tag);
+    complain_at (location, _("symbol %s redefined"), symbol->tag);

 
   if (class == nterm_sym && symbol->class != nterm_sym)
     symbol->number = nvars++;
 
   if (class == nterm_sym && symbol->class != nterm_sym)
     symbol->number = nvars++;


@@ -111,20 +170,22 @@ symbol_class_set (symbol_t *symbol, symbol_class class)
 `-------------------------------------------------*/
 
 void
 `-------------------------------------------------*/
 
 void

-symbol_user_token_number_set (symbol_t *symbol, int user_token_number)
+symbol_user_token_number_set (symbol_t *symbol,
+                             int user_token_number, location_t location)

 {
   assert (symbol->class == token_sym);
 
   if (symbol->user_token_number != USER_NUMBER_UNDEFINED
       && symbol->user_token_number != user_token_number)
 {
   assert (symbol->class == token_sym);
 
   if (symbol->user_token_number != USER_NUMBER_UNDEFINED
       && symbol->user_token_number != user_token_number)

-    complain (_("redefining user token number of %s"), symbol->tag);
+    complain_at (location, _("redefining user token number of %s"),
+                symbol->tag);

 
   symbol->user_token_number = user_token_number;
 
   symbol->user_token_number = user_token_number;

-  /* User defined EOF token? */
+  /* User defined $end token? */

   if (user_token_number == 0)
     {
   if (user_token_number == 0)
     {

-      eoftoken = symbol;
-      eoftoken->number = 0;
+      endtoken = symbol;
+      endtoken->number = 0;

       /* It is always mapped to 0, so it was already counted in
         NTOKENS.  */
       --ntokens;
       /* It is always mapped to 0, so it was already counted in
         NTOKENS.  */
       --ntokens;


@@ -159,8 +220,9 @@ symbol_check_defined (symbol_t *this)
 {
   if (this->class == unknown_sym)
     {
 {
   if (this->class == unknown_sym)
     {

-      complain
-       (_("symbol %s is used, but is not defined as a token and has no rules"),
+      complain_at
+       (this->location,
+        _("symbol %s is used, but is not defined as a token and has no rules"),

         this->tag);
       this->class = nterm_sym;
       this->number = nvars++;
         this->tag);
       this->class = nterm_sym;
       this->number = nvars++;


@@ -176,18 +238,17 @@ symbol_check_defined (symbol_t *this)
 `-------------------------------------------------------------------*/
 
 void
 `-------------------------------------------------------------------*/
 
 void

-symbol_make_alias (symbol_t *symbol, symbol_t *symval, char *typename)
+symbol_make_alias (symbol_t *symbol, symbol_t *symval, location_t loc)

 {
   if (symval->alias)
 {
   if (symval->alias)

-    warn (_("symbol `%s' used more than once as a literal string"),
+    warn_at (loc, _("symbol `%s' used more than once as a literal string"),

          symval->tag);
   else if (symbol->alias)
          symval->tag);
   else if (symbol->alias)

-    warn (_("symbol `%s' given more than one literal string"),
+    warn_at (loc, _("symbol `%s' given more than one literal string"),

          symbol->tag);
   else
     {
       symval->class = token_sym;
          symbol->tag);
   else
     {
       symval->class = token_sym;

-      symval->type_name = typename;

       symval->user_token_number = symbol->user_token_number;
       symbol->user_token_number = USER_NUMBER_ALIAS;
       symval->alias = symbol;
       symval->user_token_number = symbol->user_token_number;
       symbol->user_token_number = USER_NUMBER_ALIAS;
       symval->alias = symbol;


@@ -216,8 +277,9 @@ symbol_check_alias_consistence (symbol_t *this)
       if (this->prec != this->alias->prec)
        {
          if (this->prec != 0 && this->alias->prec != 0)
       if (this->prec != this->alias->prec)
        {
          if (this->prec != 0 && this->alias->prec != 0)

-           complain (_("conflicting precedences for %s and %s"),
-                     this->tag, this->alias->tag);
+           complain_at (this->alias->location,
+                        _("conflicting precedences for %s and %s"),
+                        this->tag, this->alias->tag);

          if (this->prec != 0)
            this->alias->prec = this->prec;
          else
          if (this->prec != 0)
            this->alias->prec = this->prec;
          else


@@ -226,10 +288,12 @@ symbol_check_alias_consistence (symbol_t *this)
 
       if (this->assoc != this->alias->assoc)
        {
 
       if (this->assoc != this->alias->assoc)
        {

-         if (this->assoc != 0 && this->alias->assoc != 0)
-           complain (_("conflicting assoc values for %s and %s"),
-                     this->tag, this->alias->tag);
-         if (this->assoc != 0)
+         if (this->assoc != undef_assoc && this->alias->assoc != undef_assoc)
+           complain_at (this->alias->location,
+                        _("conflicting associativities for %s (%s) and %s (%s)"),
+                        this->tag, assoc_to_string (this->assoc),
+                        this->alias->tag, assoc_to_string (this->alias->assoc));
+         if (this->assoc != undef_assoc)

            this->alias->assoc = this->assoc;
          else
            this->assoc = this->alias->assoc;
            this->alias->assoc = this->assoc;
          else
            this->assoc = this->alias->assoc;


@@ -258,7 +322,7 @@ symbol_pack (symbol_t *this)
         prec and assoc fields and make both the same */
       if (this->number == NUMBER_UNDEFINED)
        {
         prec and assoc fields and make both the same */
       if (this->number == NUMBER_UNDEFINED)
        {

-         if (this == eoftoken || this->alias == eoftoken)
+         if (this == endtoken || this->alias == endtoken)

            this->number = this->alias->number = 0;
          else
            {
            this->number = this->alias->number = 0;
          else
            {


@@ -295,9 +359,10 @@ symbol_translation (symbol_t *this)
     {
       /* A token which translation has already been set? */
       if (token_translations[this->user_token_number] != undeftoken->number)
     {
       /* A token which translation has already been set? */
       if (token_translations[this->user_token_number] != undeftoken->number)

-       complain (_("tokens %s and %s both assigned number %d"),
-                 symbols[token_translations[this->user_token_number]]->tag,
-                 this->tag, this->user_token_number);
+       complain_at (this->location,
+                    _("tokens %s and %s both assigned number %d"),
+                    symbols[token_translations[this->user_token_number]]->tag,
+                    this->tag, this->user_token_number);

 
       token_translations[this->user_token_number] = this->number;
     }
 
       token_translations[this->user_token_number] = this->number;
     }


@@ -349,24 +414,48 @@ symbols_new (void)
 `----------------------------------------------------------------*/
 
 symbol_t *
 `----------------------------------------------------------------*/
 
 symbol_t *

-getsym (const char *key)
+symbol_get (const char *key, location_t location)

 {
   symbol_t probe;
   symbol_t *entry;
 
 {
   symbol_t probe;
   symbol_t *entry;
 

-  (const char *) probe.tag = key;
+  /* Keep the symbol in a printable form.  */
+  key = quotearg_style (escape_quoting_style, key);
+  *(char const **) &probe.tag = key;

   entry = hash_lookup (symbol_table, &probe);
 
   if (!entry)
     {
       /* First insertion in the hash. */
   entry = hash_lookup (symbol_table, &probe);
 
   if (!entry)
     {
       /* First insertion in the hash. */

-      entry = symbol_new (key);
+      entry = symbol_new (key, location);

       hash_insert (symbol_table, entry);
     }
   return entry;
 }
 
 
       hash_insert (symbol_table, entry);
     }
   return entry;
 }
 
 

+/*------------------------------------------------------------------.
+| Generate a dummy nonterminal, whose name cannot conflict with the |
+| user's names.                                                     |
+`------------------------------------------------------------------*/
+
+symbol_t *
+dummy_symbol_get (location_t location)
+{
+  /* Incremented for each generated symbol.  */
+  static int dummy_count = 0;
+  static char buf[256];
+
+  symbol_t *sym;
+
+  sprintf (buf, "@%d", ++dummy_count);
+  sym = symbol_get (buf, location);
+  sym->class = nterm_sym;
+  sym->number = nvars++;
+  return sym;
+}
+
+

 /*-------------------.
 | Free the symbols.  |
 `-------------------*/
 /*-------------------.
 | Free the symbols.  |
 `-------------------*/


@@ -375,6 +464,7 @@ void
 symbols_free (void)
 {
   hash_free (symbol_table);
 symbols_free (void)
 {
   hash_free (symbol_table);

+  free (symbols);

 }
 
 
 }
 
 


@@ -450,8 +540,8 @@ symbols_token_translations_init (void)
   token_translations = XCALLOC (symbol_number_t, max_user_token_number + 1);
 
   /* Initialize all entries for literal tokens to 2, the internal
   token_translations = XCALLOC (symbol_number_t, max_user_token_number + 1);
 
   /* Initialize all entries for literal tokens to 2, the internal

-     token number for $undefined., which represents all invalid
-     inputs.  */
+     token number for $undefined, which represents all invalid inputs.
+     */

   for (i = 0; i < max_user_token_number + 1; i++)
     token_translations[i] = undeftoken->number;
   symbols_do (symbol_translation, NULL);
   for (i = 0; i < max_user_token_number + 1; i++)
     token_translations[i] = undeftoken->number;
   symbols_do (symbol_translation, NULL);


@@ -474,7 +564,11 @@ symbols_pack (void)
   symbols_token_translations_init ();
 
   if (startsymbol->class == unknown_sym)
   symbols_token_translations_init ();
 
   if (startsymbol->class == unknown_sym)

-    fatal (_("the start symbol %s is undefined"), startsymbol->tag);
+    fatal_at (startsymbol_location,
+             _("the start symbol %s is undefined"),
+             startsymbol->tag);

   else if (startsymbol->class == token_sym)
   else if (startsymbol->class == token_sym)

-    fatal (_("the start symbol %s is a token"), startsymbol->tag);
+    fatal_at (startsymbol_location,
+             _("the start symbol %s is a token"),
+             startsymbol->tag);

 }
 }