* src/print.c (print_shifts, print_gotos): Merge into...

[bison.git] / src / conflicts.c

diff --git a/src/conflicts.c b/src/conflicts.c
index 6e2671048042d92a69efd660272bc68a30bba762..aef33e6d3b44f4cc944dde96d71b9f90aa038245 100644 (file)
--- a/src/conflicts.c
+++ b/src/conflicts.c
@@ -1,5 +1,6 @@
 /* Find and resolve or report look-ahead conflicts for bison,
 /* Find and resolve or report look-ahead conflicts for bison,

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

 
    This file is part of Bison, the GNU Compiler Compiler.
 
 
    This file is part of Bison, the GNU Compiler Compiler.
 


@@ -19,8 +20,10 @@
    02111-1307, USA.  */
 
 #include "system.h"
    02111-1307, USA.  */
 
 #include "system.h"

+#include "bitset.h"

 #include "complain.h"
 #include "getargs.h"
 #include "complain.h"
 #include "getargs.h"

+#include "symtab.h"

 #include "files.h"
 #include "gram.h"
 #include "state.h"
 #include "files.h"
 #include "gram.h"
 #include "state.h"


@@ -29,22 +32,101 @@
 #include "reader.h"
 #include "LR0.h"
 
 #include "reader.h"
 #include "LR0.h"
 

-errs **err_table = NULL;

 /* -1 stands for not specified. */
 int expected_conflicts = -1;
 static char *conflicts = NULL;
 /* -1 stands for not specified. */
 int expected_conflicts = -1;
 static char *conflicts = NULL;

+struct obstack solved_conflicts_obstack;
+
+static bitset shiftset;
+static bitset lookaheadset;

 
 

-static unsigned *shiftset = NULL;
-static unsigned *lookaheadset = NULL;

 \f
 
 \f
 

+enum conflict_resolution_e
+  {
+    shift_resolution,
+    reduce_resolution,
+    left_resolution,
+    right_resolution,
+    nonassoc_resolution
+  };
+
+
+/*----------------------------------------------------------------.
+| Explain how an SR conflict between TOKEN and RULE was resolved: |
+| RESOLUTION.                                                     |
+`----------------------------------------------------------------*/
+

 static inline void
 static inline void

-log_resolution (int state, int LAno, int token, char *resolution)
+log_resolution (rule_t *rule, int token,
+               enum conflict_resolution_e resolution)

 {
 {

-  obstack_fgrow4 (&output_obstack,
-                 _("\
-Conflict in state %d between rule %d and token %s resolved as %s.\n"),
-                 state, LAruleno[LAno], tags[token], resolution);
+  if (report_flag & report_solved_conflicts)
+    {
+      /* The description of the resolution. */
+      switch (resolution)
+       {
+       case shift_resolution:
+       case left_resolution:
+         obstack_fgrow2 (&solved_conflicts_obstack,
+                         _("\
+    Conflict between rule %d and token %s resolved as shift"),
+                         rule->number,
+                         symbols[token]->tag);
+         break;
+       case reduce_resolution:
+       case right_resolution:
+         obstack_fgrow2 (&solved_conflicts_obstack,
+                         _("\
+    Conflict between rule %d and token %s resolved as reduce"),
+                         rule->number,
+                         symbols[token]->tag);
+         break;
+       case nonassoc_resolution:
+         obstack_fgrow2 (&solved_conflicts_obstack,
+                         _("\
+    Conflict between rule %d and token %s resolved as an error"),
+                         rule->number,
+                         symbols[token]->tag);
+         break;
+       }
+
+      /* The reason. */
+      switch (resolution)
+       {
+       case shift_resolution:
+         obstack_fgrow2 (&solved_conflicts_obstack,
+                         " (%s < %s)",
+                         rule->prec->tag,
+                         symbols[token]->tag);
+         break;
+
+       case reduce_resolution:
+         obstack_fgrow2 (&solved_conflicts_obstack,
+                         " (%s < %s)",
+                         symbols[token]->tag,
+                         rule->prec->tag);
+         break;
+
+       case left_resolution:
+         obstack_fgrow1 (&solved_conflicts_obstack,
+                         " (%%left %s)",
+                         symbols[token]->tag);
+         break;
+
+       case right_resolution:
+         obstack_fgrow1 (&solved_conflicts_obstack,
+                         " (%%right %s)",
+                         symbols[token]->tag);
+         break;
+       case nonassoc_resolution:
+         obstack_fgrow1 (&solved_conflicts_obstack,
+                         " (%%nonassoc %s)",
+                         symbols[token]->tag);
+         break;
+       }
+      obstack_sgrow (&solved_conflicts_obstack, ".\n");
+    }

 }
 
 
 }
 
 


@@ -55,23 +137,28 @@ Conflict in state %d between rule %d and token %s resolved as %s.\n"),
 `------------------------------------------------------------------*/
 
 static void
 `------------------------------------------------------------------*/
 
 static void

-flush_shift (int state, int token)
+flush_shift (state_t *state, int token)

 {
 {

-  shifts *shiftp;
-  int k, i;
+  shifts_t *shiftp = state->shifts;
+  int i;

 
 

-  shiftp = state_table[state].shift_table;
+  bitset_reset (lookaheadset, token);
+  for (i = 0; i < shiftp->nshifts; i++)
+    if (!SHIFT_IS_DISABLED (shiftp, i) && SHIFT_SYMBOL (shiftp, i) == token)
+      SHIFT_DISABLE (shiftp, i);
+}

 
 

-  if (shiftp)
-    {
-      k = shiftp->nshifts;
-      for (i = 0; i < k; i++)
-       {
-         if (shiftp->shifts[i]
-             && token == state_table[shiftp->shifts[i]].accessing_symbol)
-           (shiftp->shifts[i]) = 0;
-       }
-    }
+
+/*-------------------------------------------------------------------.
+| Turn off the reduce recorded for the specified token for the       |
+| specified lookahead.  Used when we resolve a shift-reduce conflict |
+| in favor of the shift.                                             |
+`-------------------------------------------------------------------*/
+
+static void
+flush_reduce (bitset lookaheads, int token)
+{
+  bitset_reset (lookaheads, token);

 }
 
 
 }
 
 


@@ -80,171 +167,135 @@ flush_shift (int state, int token)
 | precedence declarations.  It has already been checked that the    |
 | rule has a precedence.  A conflict is resolved by modifying the   |
 | shift or reduce tables so that there is no longer a conflict.     |
 | precedence declarations.  It has already been checked that the    |
 | rule has a precedence.  A conflict is resolved by modifying the   |
 | shift or reduce tables so that there is no longer a conflict.     |

+|                                                                   |
+| LOOKAHEAD is the number of the lookahead bitset to consider.      |

 `------------------------------------------------------------------*/
 
 static void
 `------------------------------------------------------------------*/
 
 static void

-resolve_sr_conflict (int state, int lookaheadnum)
+resolve_sr_conflict (state_t *state, int lookahead)

 {
   int i;
 {
   int i;

-  int mask;
-  unsigned *fp1;
-  unsigned *fp2;
-  int redprec;
-  errs *errp = ERRS_ALLOC (ntokens + 1);
-  short *errtokens = errp->errs;
-
-  /* find the rule to reduce by to get precedence of reduction  */
-  redprec = rule_table[LAruleno[lookaheadnum]].prec;
-
-  mask = 1;
-  fp1 = LA (lookaheadnum);
-  fp2 = lookaheadset;
+  /* Find the rule to reduce by to get precedence of reduction.  */
+  rule_t *redrule = state->lookaheads_rule[lookahead];
+  int redprec = redrule->prec->prec;
+  bitset lookaheads = state->lookaheads[lookahead];
+  errs_t *errp = errs_new (ntokens + 1);
+  errp->nerrs = 0;
+

   for (i = 0; i < ntokens; i++)
   for (i = 0; i < ntokens; i++)

-    {
-      if ((mask & *fp2 & *fp1) && sprec[i])
+    if (bitset_test (lookaheads, i)
+       && bitset_test (lookaheadset, i)
+       && symbols[i]->prec)
+      {

        /* Shift-reduce conflict occurs for token number i
           and it has a precedence.
           The precedence of shifting is that of token i.  */
        /* Shift-reduce conflict occurs for token number i
           and it has a precedence.
           The precedence of shifting is that of token i.  */

-       {
-         if (sprec[i] < redprec)
+       if (symbols[i]->prec < redprec)
+         {
+           log_resolution (redrule, i, reduce_resolution);
+           flush_shift (state, i);
+         }
+       else if (symbols[i]->prec > redprec)
+         {
+           log_resolution (redrule, i, shift_resolution);
+           flush_reduce (lookaheads, i);
+         }
+       else
+         /* Matching precedence levels.
+            For left association, keep only the reduction.
+            For right association, keep only the shift.
+            For nonassociation, keep neither.  */
+
+         switch (symbols[i]->assoc)

            {
            {

-             log_resolution (state, lookaheadnum, i, _("reduce"));
-             *fp2 &= ~mask;    /* flush the shift for this token */
+           case right_assoc:
+             log_resolution (redrule, i, right_resolution);
+             flush_reduce (lookaheads, i);
+             break;
+
+           case left_assoc:
+             log_resolution (redrule, i, left_resolution);

              flush_shift (state, i);
              flush_shift (state, i);

+             break;
+
+           case non_assoc:
+             log_resolution (redrule, i, nonassoc_resolution);
+             flush_shift (state, i);
+             flush_reduce (lookaheads, i);
+             /* Record an explicit error for this token.  */
+             errp->errs[errp->nerrs++] = i;
+             break;
+
+           case undef_assoc:
+             assert (symbols[i]->assoc != undef_assoc);
+             break;

            }
            }

-         else if (sprec[i] > redprec)
-           {
-             log_resolution (state, lookaheadnum, i, _("shift"));
-             *fp1 &= ~mask;    /* flush the reduce for this token */
-           }
-         else
-           {
-             /* Matching precedence levels.
-                For left association, keep only the reduction.
-                For right association, keep only the shift.
-                For nonassociation, keep neither.  */
-
-             switch (sassoc[i])
-               {
-               case right_assoc:
-                 log_resolution (state, lookaheadnum, i, _("shift"));
-                 break;
-
-               case left_assoc:
-                 log_resolution (state, lookaheadnum, i, _("reduce"));
-                 break;
-
-               case non_assoc:
-                 log_resolution (state, lookaheadnum, i, _("an error"));
-                 break;
-               }
-
-             if (sassoc[i] != right_assoc)
-               {
-                 *fp2 &= ~mask;        /* flush the shift for this token */
-                 flush_shift (state, i);
-               }
-             if (sassoc[i] != left_assoc)
-               {
-                 *fp1 &= ~mask;        /* flush the reduce for this token */
-               }
-             if (sassoc[i] == non_assoc)
-               {
-                 /* Record an explicit error for this token.  */
-                 *errtokens++ = i;
-               }
-           }
-       }
+      }

 
 

-      mask <<= 1;
-      if (mask == 0)
-       {
-         mask = 1;
-         fp2++;
-         fp1++;
-       }
-    }
-  errp->nerrs = errtokens - errp->errs;
-  if (errp->nerrs)
+  /* Some tokens have been explicitly made errors.  Allocate a
+     permanent errs structure for this state, to record them.  */
+  state->errs = errs_dup (errp);
+  free (errp);
+
+  if (obstack_object_size (&solved_conflicts_obstack))

     {
     {

-      /* Some tokens have been explicitly made errors.  Allocate
-         a permanent errs structure for this state, to record them.  */
-      i = (char *) errtokens - (char *) errp;
-      err_table[state] = ERRS_ALLOC (i + 1);
-      bcopy (errp, err_table[state], i);
+      obstack_1grow (&solved_conflicts_obstack, '\0');
+      state->solved_conflicts = obstack_finish (&solved_conflicts_obstack);

     }
     }

-  else
-    err_table[state] = 0;
-  free (errp);

 }
 
 
 static void
 }
 
 
 static void

-set_conflicts (int state)
+set_conflicts (state_t *state)

 {
 {

-  int i, j;
-  shifts *shiftp;
-  int symbol;
+  int i;
+  shifts_t *shiftp;

 
 

-  if (state_table[state].consistent)
+  if (state->consistent)

     return;
 
     return;
 

-  for (i = 0; i < tokensetsize; i++)
-    lookaheadset[i] = 0;
+  bitset_zero (lookaheadset);

 
 

-  shiftp = state_table[state].shift_table;
-  if (shiftp)
-    for (i = 0; i < shiftp->nshifts; i++)
-      {
-       symbol = state_table[shiftp->shifts[i]].accessing_symbol;
-       if (ISVAR (symbol))
-         break;
-       SETBIT (lookaheadset, symbol);
-      }
+  shiftp = state->shifts;
+  for (i = 0; i < shiftp->nshifts && SHIFT_IS_SHIFT (shiftp, i); i++)
+    if (!SHIFT_IS_DISABLED (shiftp, i))
+      bitset_set (lookaheadset, SHIFT_SYMBOL (shiftp, i));

 
   /* Loop over all rules which require lookahead in this state.  First
      check for shift-reduce conflict, and try to resolve using
 
   /* Loop over all rules which require lookahead in this state.  First
      check for shift-reduce conflict, and try to resolve using

-     precedence */
-  for (i = state_table[state].lookaheads;
-       i < state_table[state + 1].lookaheads;
-       ++i)
-    if (rule_table[LAruleno[i]].prec)
-      for (j = 0; j < tokensetsize; ++j)
-       if (LA (i)[j] & lookaheadset[j])
-         {
-           resolve_sr_conflict (state, i);
-           break;
-         }
-
+     precedence.  */
+  for (i = 0; i < state->nlookaheads; ++i)
+    if (state->lookaheads_rule[i]->prec
+       && state->lookaheads_rule[i]->prec->prec
+       && !bitset_disjoint_p (state->lookaheads[i], lookaheadset))
+      {
+       resolve_sr_conflict (state, i);
+       break;
+      }

 
   /* Loop over all rules which require lookahead in this state.  Check
      for conflicts not resolved above.  */
 
   /* Loop over all rules which require lookahead in this state.  Check
      for conflicts not resolved above.  */

-  for (i = state_table[state].lookaheads;
-       i < state_table[state + 1].lookaheads;
-       ++i)
+  for (i = 0; i < state->nlookaheads; ++i)

     {
     {

-      for (j = 0; j < tokensetsize; ++j)
-       if (LA (i)[j] & lookaheadset[j])
-         conflicts[state] = 1;
+      if (!bitset_disjoint_p (state->lookaheads[i], lookaheadset))
+       conflicts[state->number] = 1;

 
 

-      for (j = 0; j < tokensetsize; ++j)
-       lookaheadset[j] |= LA (i)[j];
+      bitset_or (lookaheadset, lookaheadset, state->lookaheads[i]);

     }
 }
 
 void
     }
 }
 
 void

-solve_conflicts (void)
+conflicts_solve (void)

 {
 {

-  int i;
+  state_number_t i;

 
   conflicts = XCALLOC (char, nstates);
 
   conflicts = XCALLOC (char, nstates);

-  shiftset = XCALLOC (unsigned, tokensetsize);
-  lookaheadset = XCALLOC (unsigned, tokensetsize);
-
-  err_table = XCALLOC (errs *, nstates);
+  shiftset = bitset_create (ntokens, BITSET_FIXED);
+  lookaheadset = bitset_create (ntokens, BITSET_FIXED);
+  obstack_init (&solved_conflicts_obstack);

 
   for (i = 0; i < nstates; i++)
 
   for (i = 0; i < nstates; i++)

-    set_conflicts (i);
+    set_conflicts (states[i]);

 }
 
 
 }
 
 


@@ -253,121 +304,59 @@ solve_conflicts (void)
 `---------------------------------------------*/
 
 static int
 `---------------------------------------------*/
 
 static int

-count_sr_conflicts (int state)
+count_sr_conflicts (state_t *state)

 {
   int i;
 {
   int i;

-  int k;
-  int mask;
-  shifts *shiftp;
-  unsigned *fp1;
-  unsigned *fp2;
-  unsigned *fp3;
-  int symbol;
-

   int src_count = 0;
   int src_count = 0;

+  shifts_t *shiftp = state->shifts;

 
 

-  shiftp = state_table[state].shift_table;

   if (!shiftp)
     return 0;
 
   if (!shiftp)
     return 0;
 

-  for (i = 0; i < tokensetsize; i++)
-    {
-      shiftset[i] = 0;
-      lookaheadset[i] = 0;
-    }
-
-  k = shiftp->nshifts;
-  for (i = 0; i < k; i++)
-    {
-      if (!shiftp->shifts[i])
-       continue;
-      symbol = state_table[shiftp->shifts[i]].accessing_symbol;
-      if (ISVAR (symbol))
-       break;
-      SETBIT (shiftset, symbol);
-    }
-
-  k = state_table[state + 1].lookaheads;
-  fp3 = lookaheadset + tokensetsize;
-
-  for (i = state_table[state].lookaheads; i < k; i++)
-    {
-      fp1 = LA (i);
-      fp2 = lookaheadset;
+  bitset_zero (lookaheadset);
+  bitset_zero (shiftset);

 
 

-      while (fp2 < fp3)
-       *fp2++ |= *fp1++;
-    }
+  for (i = 0; i < shiftp->nshifts && SHIFT_IS_SHIFT (shiftp, i); i++)
+    if (!SHIFT_IS_DISABLED (shiftp, i))
+      bitset_set (shiftset, SHIFT_SYMBOL (shiftp, i));

 
 

-  fp1 = shiftset;
-  fp2 = lookaheadset;
+  for (i = 0; i < state->nlookaheads; ++i)
+    bitset_or (lookaheadset, lookaheadset, state->lookaheads[i]);

 
 

-  while (fp2 < fp3)
-    *fp2++ &= *fp1++;
+  bitset_and (lookaheadset, lookaheadset, shiftset);

 
 

-  mask = 1;
-  fp2 = lookaheadset;
-  for (i = 0; i < ntokens; i++)
-    {
-      if (mask & *fp2)
-       src_count++;
-
-      mask <<= 1;
-      if (mask == 0)
-       {
-         mask = 1;
-         fp2++;
-       }
-    }
+  src_count = bitset_count (lookaheadset);

 
   return src_count;
 }
 
 
 
   return src_count;
 }
 
 

-/*----------------------------------------------.
-| Count the number of reduce/reduce conflicts.  |
-`----------------------------------------------*/
+/*----------------------------------------------------------------.
+| Count the number of reduce/reduce conflicts.  If ONE_PER_TOKEN, |
+| count one conflict for each token that has any reduce/reduce    |
+| conflicts.  Otherwise, count one conflict for each pair of      |
+| conflicting reductions.                                         |
++`----------------------------------------------------------------*/

 
 static int
 
 static int

-count_rr_conflicts (int state)
+count_rr_conflicts (state_t *state, int one_per_token)

 {
   int i;
 {
   int i;

-  unsigned mask;
-  unsigned *baseword;
-

   int rrc_count = 0;
 
   int rrc_count = 0;
 

-  int m = state_table[state].lookaheads;
-  int n = state_table[state + 1].lookaheads;
-
-  if (n - m < 2)
+  if (state->nlookaheads < 2)

     return 0;
 
     return 0;
 

-  mask = 1;
-  baseword = LA (m);

   for (i = 0; i < ntokens; i++)
     {
   for (i = 0; i < ntokens; i++)
     {

-      unsigned *wordp = baseword;
-

       int count = 0;
       int j;
       int count = 0;
       int j;

-      for (j = m; j < n; j++)
-       {
-         if (mask & *wordp)
-           count++;
-
-         wordp += tokensetsize;
-       }
+      for (j = 0; j < state->nlookaheads; ++j)
+       if (bitset_test (state->lookaheads[j], i))
+         count++;

 
       if (count >= 2)
 
       if (count >= 2)

-       rrc_count++;
-
-      mask <<= 1;
-      if (mask == 0)
-       {
-         mask = 1;
-         baseword++;
-       }
+       rrc_count += one_per_token ? 1 : count-1;

     }
 
   return rrc_count;
     }
 
   return rrc_count;


@@ -419,14 +408,42 @@ conflict_report (int src_num, int rrc_num)
 void
 conflicts_output (FILE *out)
 {
 void
 conflicts_output (FILE *out)
 {

-  int i;
+  bool printed_sth = FALSE;
+  state_number_t i;

   for (i = 0; i < nstates; i++)
     if (conflicts[i])
       {
        fprintf (out, _("State %d contains "), i);
   for (i = 0; i < nstates; i++)
     if (conflicts[i])
       {
        fprintf (out, _("State %d contains "), i);

-       fputs (conflict_report (count_sr_conflicts (i),
-                               count_rr_conflicts (i)), out);
+       fputs (conflict_report (count_sr_conflicts (states[i]),
+                               count_rr_conflicts (states[i], TRUE)), out);
+       printed_sth = TRUE;
+      }
+  if (printed_sth)
+    fputs ("\n\n", out);
+}
+
+/*--------------------------------------------------------.
+| Total the number of S/R and R/R conflicts.  Unlike the  |
+| code in conflicts_output, however, count EACH pair of   |
+| reductions for the same state and lookahead as one      |
+| conflict.                                              |
+`--------------------------------------------------------*/
+
+int
+conflicts_total_count (void)
+{
+  state_number_t i;
+  int count;
+
+  /* Conflicts by state.  */
+  count = 0;
+  for (i = 0; i < nstates; i++)
+    if (conflicts[i])
+      {
+       count += count_sr_conflicts (states[i]);
+       count += count_rr_conflicts (states[i], FALSE);

       }
       }

+  return count;

 }
 
 
 }
 
 


@@ -437,284 +454,69 @@ conflicts_output (FILE *out)
 void
 conflicts_print (void)
 {
 void
 conflicts_print (void)
 {

-  int i;
+  /* Is the number of SR conflicts OK?  Either EXPECTED_CONFLICTS is
+     not set, and then we want 0 SR, or else it is specified, in which
+     case we want equality.  */
+  int src_ok = 0;

 
   int src_total = 0;
   int rrc_total = 0;
 
   /* Conflicts by state.  */
 
   int src_total = 0;
   int rrc_total = 0;
 
   /* Conflicts by state.  */

-  for (i = 0; i < nstates; i++)
-    if (conflicts[i])
-      {
-       src_total += count_sr_conflicts (i);
-       rrc_total += count_rr_conflicts (i);
-      }
+  {
+    state_number_t i;

 
 

-  /* Report the total number of conflicts on STDERR.  */
-  if (src_total || rrc_total)
-    {
-      if (yacc_flag)
+    for (i = 0; i < nstates; i++)
+      if (conflicts[i])

        {
        {

-         /* If invoked with `--yacc', use the output format specified by
-            POSIX.  */
-         fprintf (stderr, _("conflicts: "));
-         if (src_total > 0)
-           fprintf (stderr, _(" %d shift/reduce"), src_total);
-         if (src_total > 0 && rrc_total > 0)
-           fprintf (stderr, ",");
-         if (rrc_total > 0)
-           fprintf (stderr, _(" %d reduce/reduce"), rrc_total);
-         putc ('\n', stderr);
+         src_total += count_sr_conflicts (states[i]);
+         rrc_total += count_rr_conflicts (states[i], TRUE);

        }
        }

-      else
-       {
-         fprintf (stderr, _("%s contains "), infile);
-         fputs (conflict_report (src_total, rrc_total), stderr);
-       }
-    }
-
-  if (expected_conflicts != -1
-      && src_total != expected_conflicts)
-    {
-      complain_message_count++;
-      fprintf (stderr, ngettext ("expected %d shift/reduce conflict\n",
-                                "expected %d shift/reduce conflicts\n",
-                                expected_conflicts),
-              expected_conflicts);
-    }
-}
+  }

 
 

+  src_ok = src_total == (expected_conflicts == -1 ? 0 : expected_conflicts);

 
 

-void
-print_reductions (FILE *out, int state)
-{
-  int i;
-  int j;
-  int k;
-  unsigned *fp1;
-  unsigned *fp2;
-  unsigned *fp3;
-  unsigned *fp4;
-  int rule;
-  int symbol;
-  unsigned mask;
-  int m;
-  int n;
-  int default_LA;
-  int default_rule = 0;
-  int cmax;
-  int count;
-  shifts *shiftp;
-  errs *errp;
-  int nodefault = 0;
-
-  for (i = 0; i < tokensetsize; i++)
-    shiftset[i] = 0;
+  /* If there are no RR conflicts, and as many SR conflicts as
+     expected, then there is nothing to report.  */
+  if (!rrc_total && src_ok)
+    return;

 
 

-  shiftp = state_table[state].shift_table;
-  if (shiftp)
+  /* Report the total number of conflicts on STDERR.  */
+  if (yacc_flag)

     {
     {

-      k = shiftp->nshifts;
-      for (i = 0; i < k; i++)
-       {
-         if (!shiftp->shifts[i])
-           continue;
-         symbol = state_table[shiftp->shifts[i]].accessing_symbol;
-         if (ISVAR (symbol))
-           break;
-         /* if this state has a shift for the error token,
-            don't use a default rule.  */
-         if (symbol == error_token_number)
-           nodefault = 1;
-         SETBIT (shiftset, symbol);
-       }
+      /* If invoked with `--yacc', use the output format specified by
+        POSIX.  */
+      fprintf (stderr, _("conflicts: "));
+      if (src_total > 0)
+       fprintf (stderr, _(" %d shift/reduce"), src_total);
+      if (src_total > 0 && rrc_total > 0)
+       fprintf (stderr, ",");
+      if (rrc_total > 0)
+       fprintf (stderr, _(" %d reduce/reduce"), rrc_total);
+      putc ('\n', stderr);

     }
     }

-
-  errp = err_table[state];
-  if (errp)
+  else

     {
     {

-      k = errp->nerrs;
-      for (i = 0; i < k; i++)
-       {
-         if (!errp->errs[i])
-           continue;
-         symbol = errp->errs[i];
-         SETBIT (shiftset, symbol);
-       }
+      fprintf (stderr, _("%s contains "), infile);
+      fputs (conflict_report (src_total, rrc_total), stderr);

     }
 
     }
 

-  m = state_table[state].lookaheads;
-  n = state_table[state + 1].lookaheads;
-
-  if (n - m == 1 && !nodefault)
-    {
-      default_rule = LAruleno[m];
-
-      fp1 = LA (m);
-      fp2 = shiftset;
-      fp3 = lookaheadset;
-      fp4 = lookaheadset + tokensetsize;
-
-      while (fp3 < fp4)
-       *fp3++ = *fp1++ & *fp2++;
-
-      mask = 1;
-      fp3 = lookaheadset;
-
-      for (i = 0; i < ntokens; i++)
-       {
-         if (mask & *fp3)
-           fprintf (out, _("    %-4s\t[reduce using rule %d (%s)]\n"),
-                    tags[i], default_rule,
-                    tags[rule_table[default_rule].lhs]);
-
-         mask <<= 1;
-         if (mask == 0)
-           {
-             mask = 1;
-             fp3++;
-           }
-       }
-
-      fprintf (out, _("    $default\treduce using rule %d (%s)\n\n"),
-              default_rule, tags[rule_table[default_rule].lhs]);
-    }
-  else if (n - m >= 1)
+  if (expected_conflicts != -1 && !src_ok)

     {
     {

-      cmax = 0;
-      default_LA = -1;
-      fp4 = lookaheadset + tokensetsize;
-
-      if (!nodefault)
-       for (i = m; i < n; i++)
-         {
-           fp1 = LA (i);
-           fp2 = shiftset;
-           fp3 = lookaheadset;
-
-           while (fp3 < fp4)
-             *fp3++ = *fp1++ & (~(*fp2++));
-
-           count = 0;
-           mask = 1;
-           fp3 = lookaheadset;
-           for (j = 0; j < ntokens; j++)
-             {
-               if (mask & *fp3)
-                 count++;
-
-               mask <<= 1;
-               if (mask == 0)
-                 {
-                   mask = 1;
-                   fp3++;
-                 }
-             }
-
-           if (count > cmax)
-             {
-               cmax = count;
-               default_LA = i;
-               default_rule = LAruleno[i];
-             }
-
-           fp2 = shiftset;
-           fp3 = lookaheadset;
-
-           while (fp3 < fp4)
-             *fp2++ |= *fp3++;
-         }
-
-      for (i = 0; i < tokensetsize; i++)
-       shiftset[i] = 0;
-
-      if (shiftp)
-       {
-         k = shiftp->nshifts;
-         for (i = 0; i < k; i++)
-           {
-             if (!shiftp->shifts[i])
-               continue;
-             symbol = state_table[shiftp->shifts[i]].accessing_symbol;
-             if (ISVAR (symbol))
-               break;
-             SETBIT (shiftset, symbol);
-           }
-       }
-
-      mask = 1;
-      fp1 = LA (m);
-      fp2 = shiftset;
-      for (i = 0; i < ntokens; i++)
-       {
-         int defaulted = 0;
-
-         if (mask & *fp2)
-           count = 1;
-         else
-           count = 0;
-
-         fp3 = fp1;
-         for (j = m; j < n; j++)
-           {
-             if (mask & *fp3)
-               {
-                 if (count == 0)
-                   {
-                     if (j != default_LA)
-                       {
-                         rule = LAruleno[j];
-                         fprintf (out,
-                                  _("    %-4s\treduce using rule %d (%s)\n"),
-                                  tags[i], rule, tags[rule_table[rule].lhs]);
-                       }
-                     else
-                       defaulted = 1;
-
-                     count++;
-                   }
-                 else
-                   {
-                     if (defaulted)
-                       {
-                         rule = LAruleno[default_LA];
-                         fprintf (out,
-                                  _("    %-4s\treduce using rule %d (%s)\n"),
-                                  tags[i], rule, tags[rule_table[rule].lhs]);
-                         defaulted = 0;
-                       }
-                     rule = LAruleno[j];
-                     fprintf (out,
-                              _("    %-4s\t[reduce using rule %d (%s)]\n"),
-                              tags[i], rule, tags[rule_table[rule].lhs]);
-                   }
-               }
-
-             fp3 += tokensetsize;
-           }
-
-         mask <<= 1;
-         if (mask == 0)
-           {
-             mask = 1;
-             /* We tried incrementing just fp1, and just fp2; both seem wrong.
-                It seems necessary to increment both in sync.  */
-             fp1++;
-             fp2++;
-           }
-       }
-
-      if (default_LA >= 0)
-       fprintf (out, _("    $default\treduce using rule %d (%s)\n"),
-                default_rule, tags[rule_table[default_rule].lhs]);
+      complain_message_count++;
+      fprintf (stderr, ngettext ("expected %d shift/reduce conflict\n",
+                                "expected %d shift/reduce conflicts\n",
+                                expected_conflicts),
+              expected_conflicts);

     }
 }
 
 
 void
     }
 }
 
 
 void

-free_conflicts (void)
+conflicts_free (void)

 {
   XFREE (conflicts);
 {
   XFREE (conflicts);

-  XFREE (shiftset);
-  XFREE (lookaheadset);
+  bitset_free (shiftset);
+  bitset_free (lookaheadset);
+  obstack_free (&solved_conflicts_obstack, NULL);

 }
 }