POSIX: warn if %prec's token was not defined.

[bison.git] / src / print.c

diff --git a/src/print.c b/src/print.c
index 157b25c6b54238f699d5fd442fa45f14fd68b9bb..41cd19a01ef3dca2eb13551282a78b1a4fbe351b 100644 (file)
--- a/src/print.c
+++ b/src/print.c
@@ -1,7 +1,7 @@
 /* Print information on generated parser, for bison,
 
-   Copyright (C) 1984, 1986, 1989, 2000, 2001, 2002, 2003, 2004, 2005, 2007
-   Free Software Foundation, Inc.
+   Copyright (C) 1984, 1986, 1989, 2000, 2001, 2002, 2003, 2004, 2005,
+   2007, 2009 Free Software Foundation, Inc.
 
    This file is part of Bison, the GNU Compiler Compiler.
 
@@ -31,6 +31,7 @@
 #include "getargs.h"
 #include "gram.h"
 #include "lalr.h"
+#include "muscle-tab.h"
 #include "print.h"
 #include "reader.h"
 #include "reduce.h"
@@ -110,7 +111,8 @@ print_core (FILE *out, state *s)
        fprintf (out, " %s", symbols[*sp]->tag);
 
       /* Display the lookahead tokens?  */
-      if (report_flag & report_lookahead_tokens)
+      if (report_flag & report_lookahead_tokens
+          && item_number_is_rule_number (*sp1))
        state_rule_lookahead_tokens_print (s, &rules[r], out);
 
       fputc ('\n', out);
@@ -240,15 +242,16 @@ print_reductions (FILE *out, state *s)
 {
   transitions *trans = s->transitions;
   reductions *reds = s->reductions;
-  rule *default_rule = NULL;
+  rule *default_reduction = NULL;
   size_t width = 0;
   int i, j;
+  bool default_reduction_only = true;
 
   if (reds->num == 0)
     return;
 
   if (yydefact[s->number] != 0)
-    default_rule = &rules[yydefact[s->number] - 1];
+    default_reduction = &rules[yydefact[s->number] - 1];
 
   bitset_zero (no_reduce_set);
   FOR_EACH_SHIFT (trans, i)
@@ -258,7 +261,7 @@ print_reductions (FILE *out, state *s)
       bitset_set (no_reduce_set, s->errs->symbols[i]->number);
 
   /* Compute the width of the lookahead token column.  */
-  if (default_rule)
+  if (default_reduction)
     width = strlen (_("$default"));
 
   if (reds->lookahead_tokens)
@@ -271,7 +274,7 @@ print_reductions (FILE *out, state *s)
            {
              if (! count)
                {
-                 if (reds->rules[j] != default_rule)
+                 if (reds->rules[j] != default_reduction)
                    max_length (&width, symbols[i]->tag);
                  count = true;
                }
@@ -295,26 +298,32 @@ print_reductions (FILE *out, state *s)
       {
        bool defaulted = false;
        bool count = bitset_test (no_reduce_set, i);
+        if (count)
+          default_reduction_only = false;
 
        for (j = 0; j < reds->num; ++j)
          if (bitset_test (reds->lookahead_tokens[j], i))
            {
              if (! count)
                {
-                 if (reds->rules[j] != default_rule)
-                   print_reduction (out, width,
-                                    symbols[i]->tag,
-                                    reds->rules[j], true);
+                 if (reds->rules[j] != default_reduction)
+                    {
+                      default_reduction_only = false;
+                      print_reduction (out, width,
+                                       symbols[i]->tag,
+                                       reds->rules[j], true);
+                    }
                  else
                    defaulted = true;
                  count = true;
                }
              else
                {
+                  default_reduction_only = false;
                  if (defaulted)
                    print_reduction (out, width,
                                     symbols[i]->tag,
-                                    default_rule, true);
+                                    default_reduction, true);
                  defaulted = false;
                  print_reduction (out, width,
                                   symbols[i]->tag,
@@ -323,9 +332,17 @@ print_reductions (FILE *out, state *s)
            }
       }
 
-  if (default_rule)
-    print_reduction (out, width,
-                    _("$default"), default_rule, true);
+  if (default_reduction)
+    {
+      char *default_reductions =
+        muscle_percent_define_get ("lr.default-reductions");
+      print_reduction (out, width, _("$default"), default_reduction, true);
+      aver (0 == strcmp (default_reductions, "all")
+            || (0 == strcmp (default_reductions, "consistent")
+                && default_reduction_only)
+            || (reds->num == 1 && reds->rules[0]->number == 0));
+      free (default_reductions);
+    }
 }
 
 
@@ -491,7 +508,8 @@ print_results (void)
 
   reduce_output (out);
   grammar_rules_partial_print (out,
-                              _("Rules never reduced"), rule_never_reduced_p);
+                              _("Rules useless in parser due to conflicts"),
+                                 rule_useless_in_parser_p);
   conflicts_output (out);
 
   print_grammar (out);