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

[bison.git] / src / reader.c

diff --git a/src/reader.c b/src/reader.c
index 3482d6355aa3e12e4b60d84faf5c41637cbc344c..d7527158aca5549dc388a416dad300191056f371 100644 (file)
--- a/src/reader.c
+++ b/src/reader.c
@@ -34,7 +34,6 @@
 #include "conflicts.h"
 #include "muscle_tab.h"
 
 #include "conflicts.h"
 #include "muscle_tab.h"
 

-int lineno;

 static symbol_list_t *grammar = NULL;
 static int start_flag = 0;
 merger_list *merge_functions;
 static symbol_list_t *grammar = NULL;
 static int start_flag = 0;
 merger_list *merge_functions;


@@ -113,7 +112,8 @@ epilogue_set (const char *epilogue, location_t location)
 `-------------------------------------------------------------------*/
 
 static int
 `-------------------------------------------------------------------*/
 
 static int

-get_merge_function (const char* name, const char* type)
+get_merge_function (const char* name, const char* type,
+                   location_t loc)

 {
   merger_list *syms;
   merger_list head;
 {
   merger_list *syms;
   merger_list head;


@@ -129,15 +129,17 @@ get_merge_function (const char* name, const char* type)
   for (syms = &head, n = 1; syms->next != NULL; syms = syms->next, n += 1)
     if (strcmp (name, syms->next->name) == 0)
       break;
   for (syms = &head, n = 1; syms->next != NULL; syms = syms->next, n += 1)
     if (strcmp (name, syms->next->name) == 0)
       break;

-  if (syms->next == NULL) {
-    syms->next = XMALLOC (merger_list, 1);
-    syms->next->name = strdup (name);
-    syms->next->type = strdup (type);
-    syms->next->next = NULL;
-    merge_functions = head.next;
-  } else if (strcmp (type, syms->next->type) != 0)
-    warn (_("result type clash on merge function %s: `%s' vs. `%s'"),
-         name, type, syms->next->type);
+  if (syms->next == NULL)
+    {
+      syms->next = XMALLOC (merger_list, 1);
+      syms->next->name = xstrdup (name);
+      syms->next->type = xstrdup (type);
+      syms->next->next = NULL;
+      merge_functions = head.next;
+    }
+  else if (strcmp (type, syms->next->type) != 0)
+    warn_at (loc, _("result type clash on merge function %s: `%s' vs. `%s'"),
+            name, type, syms->next->type);

   return n;
 }
 
   return n;
 }
 


@@ -367,7 +369,7 @@ grammar_current_rule_merge_set (const char* name, location_t location)
   if (current_rule->merger != 0)
     complain_at (location, _("only one %%merge allowed per rule"));
   current_rule->merger =
   if (current_rule->merger != 0)
     complain_at (location, _("only one %%merge allowed per rule"));
   current_rule->merger =

-    get_merge_function (name, current_rule->sym->type_name);
+    get_merge_function (name, current_rule->sym->type_name, location);

 }
 
 /* Attach a SYMBOL to the current rule.  If needed, move the previous
 }
 
 /* Attach a SYMBOL to the current rule.  If needed, move the previous


@@ -404,11 +406,11 @@ static void
 packgram (void)
 {
   unsigned int itemno = 0;
 packgram (void)
 {
   unsigned int itemno = 0;

-  rule_number_t ruleno = 1;
+  rule_number_t ruleno = 0;

   symbol_list_t *p = grammar;
 
   ritem = XCALLOC (item_number_t, nritems);
   symbol_list_t *p = grammar;
 
   ritem = XCALLOC (item_number_t, nritems);

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

 
   while (p)
     {
 
   while (p)
     {


@@ -445,7 +447,7 @@ 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)
       ++ruleno;
 
       if (p)


@@ -454,7 +456,7 @@ packgram (void)
 
   assert (itemno == nritems);
 
 
   assert (itemno == nritems);
 

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

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


@@ -469,15 +471,14 @@ void
 reader (void)
 {
   gram_control_t gram_control;
 reader (void)
 {
   gram_control_t gram_control;

-  lineno = 1;

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

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

 
   /* Construct the error token */
   errtoken = symbol_get ("error", empty_location);
 
   /* Construct the error token */
   errtoken = symbol_get ("error", empty_location);


@@ -486,7 +487,7 @@ reader (void)
 
   /* Construct a token that represents all undefined literal tokens.
      It is always token number 2.  */
 
   /* Construct a token that represents all undefined literal tokens.
      It is always token number 2.  */

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

   undeftoken->class = token_sym;
   undeftoken->number = ntokens++;
 
   undeftoken->class = token_sym;
   undeftoken->number = ntokens++;
 


@@ -502,6 +503,11 @@ reader (void)
   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 (complain_message_count)
+    exit (1);
+

   /* 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"));


@@ -509,25 +515,25 @@ 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 = symbol_get ("$", empty_location);
-      eoftoken->class = token_sym;
-      eoftoken->number = 0;
+      endtoken = symbol_get ("$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_t *p = symbol_list_new (axiom, empty_location);
+    symbol_list_t *p = symbol_list_new (accept, empty_location);

     p->location = grammar->location;
     p->next = symbol_list_new (startsymbol, empty_location);
     p->location = grammar->location;
     p->next = symbol_list_new (startsymbol, empty_location);

-    p->next->next = symbol_list_new (eoftoken, 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;
     p->next->next->next = symbol_list_new (NULL, empty_location);
     p->next->next->next->next = grammar;
     nrules += 1;