]> git.saurik.com Git - bison.git/blobdiff - src/conflicts.c
Merge branch 'maint'
[bison.git] / src / conflicts.c
index df3c931ddc2b1900670324dff0c03e42f4a222c7..f8ed17727eb36bda9ce9bec2e54388a51ddb5914 100644 (file)
-/* Find and resolve or report look-ahead conflicts for bison,
-   Copyright (C) 1984, 1989, 1992, 2000, 2001, 2002
-   Free Software Foundation, Inc.
+/* Find and resolve or report lookahead conflicts for bison,
+
+   Copyright (C) 1984, 1989, 1992, 2000-2012 Free Software Foundation,
+   Inc.
 
    This file is part of Bison, the GNU Compiler Compiler.
 
-   Bison is free software; you can redistribute it and/or modify it
-   under the terms of the GNU General Public License as published by
-   the Free Software Foundation; either version 2, or (at your option)
-   any later version.
+   This program is free software: you can redistribute it and/or modify
+   it under the terms of the GNU General Public License as published by
+   the Free Software Foundation, either version 3 of the License, or
+   (at your option) any later version.
 
-   Bison is distributed in the hope that it will be useful, but
-   WITHOUT ANY WARRANTY; without even the implied warranty of
-   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
-   General Public License for more details.
+   This program is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+   GNU General Public License for more details.
 
    You should have received a copy of the GNU General Public License
-   along with Bison; see the file COPYING.  If not, write to the Free
-   Software Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA
-   02111-1307, USA.  */
+   along with this program.  If not, see <http://www.gnu.org/licenses/>.  */
 
+#include <config.h>
 #include "system.h"
-#include "bitset.h"
+
+#include <bitset.h>
+
+#include "LR0.h"
 #include "complain.h"
-#include "getargs.h"
-#include "symtab.h"
+#include "conflicts.h"
 #include "files.h"
+#include "getargs.h"
 #include "gram.h"
-#include "state.h"
 #include "lalr.h"
-#include "conflicts.h"
+#include "print-xml.h"
 #include "reader.h"
-#include "LR0.h"
+#include "state.h"
+#include "symtab.h"
 
 /* -1 stands for not specified. */
-int expected_conflicts = -1;
-static char *conflicts = NULL;
+int expected_sr_conflicts = -1;
+int expected_rr_conflicts = -1;
+static char *conflicts;
+static struct obstack solved_conflicts_obstack;
+static struct obstack solved_conflicts_xml_obstack;
+
+static bitset shift_set;
+static bitset lookahead_set;
 
-static bitset shiftset;
-static bitset lookaheadset;
 \f
 
+enum conflict_resolution
+  {
+    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
-log_resolution (state_t *state, int LAno, int token, const char *resolution)
+log_resolution (rule *r, symbol_number token,
+                enum conflict_resolution resolution)
 {
-  if (report_flag & report_states)
-    obstack_fgrow4 (&output_obstack,
-                   _("\
-Conflict in state %d between rule %d and token %s resolved as %s.\n"),
-                   state->number,
-                   LArule[LAno]->number,
-                   symbols[token]->tag,
-                   resolution);
+  if (report_flag & report_solved_conflicts)
+    {
+      /* The description of the resolution. */
+      switch (resolution)
+        {
+        case shift_resolution:
+        case right_resolution:
+          obstack_printf (&solved_conflicts_obstack,
+                          _("    Conflict between rule %d and token %s"
+                            " resolved as shift"),
+                          r->number,
+                          symbols[token]->tag);
+          break;
+
+        case reduce_resolution:
+        case left_resolution:
+          obstack_printf (&solved_conflicts_obstack,
+                          _("    Conflict between rule %d and token %s"
+                            " resolved as reduce"),
+                          r->number,
+                          symbols[token]->tag);
+          break;
+
+        case nonassoc_resolution:
+          obstack_printf (&solved_conflicts_obstack,
+                          _("    Conflict between rule %d and token %s"
+                            " resolved as an error"),
+                          r->number,
+                          symbols[token]->tag);
+          break;
+        }
+
+      /* The reason. */
+      switch (resolution)
+        {
+        case shift_resolution:
+          obstack_printf (&solved_conflicts_obstack,
+                          " (%s < %s)",
+                          r->prec->tag,
+                          symbols[token]->tag);
+          break;
+
+        case reduce_resolution:
+          obstack_printf (&solved_conflicts_obstack,
+                          " (%s < %s)",
+                          symbols[token]->tag,
+                          r->prec->tag);
+          break;
+
+        case left_resolution:
+          obstack_printf (&solved_conflicts_obstack,
+                          " (%%left %s)",
+                          symbols[token]->tag);
+          break;
+
+        case right_resolution:
+          obstack_printf (&solved_conflicts_obstack,
+                          " (%%right %s)",
+                          symbols[token]->tag);
+          break;
+
+        case nonassoc_resolution:
+          obstack_printf (&solved_conflicts_obstack,
+                          " (%%nonassoc %s)",
+                          symbols[token]->tag);
+          break;
+        }
+
+      obstack_sgrow (&solved_conflicts_obstack, ".\n");
+    }
+
+  /* XML report */
+  if (xml_flag)
+    {
+      /* The description of the resolution. */
+      switch (resolution)
+        {
+        case shift_resolution:
+        case right_resolution:
+          obstack_printf (&solved_conflicts_xml_obstack,
+                          "        <resolution rule=\"%d\" symbol=\"%s\""
+                          " type=\"shift\">",
+                          r->number,
+                          xml_escape (symbols[token]->tag));
+          break;
+
+        case reduce_resolution:
+        case left_resolution:
+          obstack_printf (&solved_conflicts_xml_obstack,
+                          "        <resolution rule=\"%d\" symbol=\"%s\""
+                          " type=\"reduce\">",
+                          r->number,
+                          xml_escape (symbols[token]->tag));
+          break;
+
+        case nonassoc_resolution:
+          obstack_printf (&solved_conflicts_xml_obstack,
+                          "        <resolution rule=\"%d\" symbol=\"%s\""
+                          " type=\"error\">",
+                          r->number,
+                          xml_escape (symbols[token]->tag));
+          break;
+        }
+
+      /* The reason. */
+      switch (resolution)
+        {
+        case shift_resolution:
+          obstack_printf (&solved_conflicts_xml_obstack,
+                          "%s &lt; %s",
+                          xml_escape_n (0, r->prec->tag),
+                          xml_escape_n (1, symbols[token]->tag));
+          break;
+
+        case reduce_resolution:
+          obstack_printf (&solved_conflicts_xml_obstack,
+                          "%s &lt; %s",
+                          xml_escape_n (0, symbols[token]->tag),
+                          xml_escape_n (1, r->prec->tag));
+          break;
+
+        case left_resolution:
+          obstack_printf (&solved_conflicts_xml_obstack,
+                          "%%left %s",
+                          xml_escape (symbols[token]->tag));
+          break;
+
+        case right_resolution:
+          obstack_printf (&solved_conflicts_xml_obstack,
+                          "%%right %s",
+                          xml_escape (symbols[token]->tag));
+          break;
+
+        case nonassoc_resolution:
+          obstack_printf (&solved_conflicts_xml_obstack,
+                          "%%nonassoc %s",
+                          xml_escape (symbols[token]->tag));
+      break;
+        }
+
+      obstack_sgrow (&solved_conflicts_xml_obstack, "</resolution>\n");
+    }
 }
 
 
 /*------------------------------------------------------------------.
 | Turn off the shift recorded for the specified token in the        |
 | specified state.  Used when we resolve a shift-reduce conflict in |
-| favor of the reduction.                                           |
+| favor of the reduction or as an error (%nonassoc).                |
 `------------------------------------------------------------------*/
 
 static void
-flush_shift (state_t *state, int token)
+flush_shift (state *s, int token)
 {
-  shifts *shiftp = state->shifts;
+  transitions *trans = s->transitions;
   int i;
 
-  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);
+  bitset_reset (lookahead_set, token);
+  for (i = 0; i < trans->num; i++)
+    if (!TRANSITION_IS_DISABLED (trans, i)
+        && TRANSITION_SYMBOL (trans, i) == token)
+      TRANSITION_DISABLE (trans, i);
 }
 
 
-/*-------------------------------------------------------------------.
-| 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.                                             |
-`-------------------------------------------------------------------*/
+/*--------------------------------------------------------------------.
+| Turn off the reduce recorded for the specified token in the         |
+| specified lookahead set.  Used when we resolve a shift-reduce       |
+| conflict in favor of the shift or as an error (%nonassoc).          |
+`--------------------------------------------------------------------*/
 
 static void
-flush_reduce (int lookahead, int token)
+flush_reduce (bitset lookahead_tokens, int token)
 {
-  bitset_reset (LA[lookahead], token);
+  bitset_reset (lookahead_tokens, token);
 }
 
 
@@ -91,120 +249,172 @@ flush_reduce (int lookahead, 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.     |
+|                                                                   |
+| RULENO is the number of the lookahead bitset to consider.         |
+|                                                                   |
+| ERRORS and NERRS can be used to store discovered explicit         |
+| errors.                                                           |
 `------------------------------------------------------------------*/
 
 static void
-resolve_sr_conflict (state_t *state, int lookahead)
+resolve_sr_conflict (state *s, int ruleno, symbol **errors, int *nerrs)
 {
-  int i;
-  /* find the rule to reduce by to get precedence of reduction  */
-  int redprec = LArule[lookahead]->prec->prec;
-  errs *errp = errs_new (ntokens + 1);
-  errp->nerrs = 0;
+  symbol_number i;
+  reductions *reds = s->reductions;
+  /* Find the rule to reduce by to get precedence of reduction.  */
+  rule *redrule = reds->rules[ruleno];
+  int redprec = redrule->prec->prec;
+  bitset lookahead_tokens = reds->lookahead_tokens[ruleno];
 
   for (i = 0; i < ntokens; i++)
-    if (bitset_test (LA[lookahead], i)
-       && bitset_test (lookaheadset, i)
-       && symbols[i]->prec)
+    if (bitset_test (lookahead_tokens, i)
+        && bitset_test (lookahead_set, 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.  */
-       if (symbols[i]->prec < redprec)
-         {
-           log_resolution (state, lookahead, i, _("reduce"));
-           flush_shift (state, i);
-         }
-       else if (symbols[i]->prec > redprec)
-         {
-           log_resolution (state, lookahead, i, _("shift"));
-           flush_reduce (lookahead, 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)
-           {
-           case right_assoc:
-             log_resolution (state, lookahead, i, _("shift"));
-             flush_reduce (lookahead, i);
-             break;
-
-           case left_assoc:
-             log_resolution (state, lookahead, i, _("reduce"));
-             flush_shift (state, i);
-             break;
-
-           case non_assoc:
-             log_resolution (state, lookahead, i, _("an error"));
-             flush_shift (state, i);
-             flush_reduce (lookahead, i);
-             /* Record an explicit error for this token.  */
-             errp->errs[errp->nerrs++] = i;
-             break;
-           }
+        /* Shift-reduce conflict occurs for token number i
+           and it has a precedence.
+           The precedence of shifting is that of token i.  */
+        if (symbols[i]->prec < redprec)
+          {
+            log_resolution (redrule, i, reduce_resolution);
+            flush_shift (s, i);
+          }
+        else if (symbols[i]->prec > redprec)
+          {
+            log_resolution (redrule, i, shift_resolution);
+            flush_reduce (lookahead_tokens, i);
+          }
+        else
+          /* Matching precedence levels.
+             For non-defined associativity, keep both: unexpected
+             associativity conflict.
+             For left associativity, keep only the reduction.
+             For right associativity, keep only the shift.
+             For nonassociativity, keep neither.  */
+
+          switch (symbols[i]->assoc)
+            {
+            case undef_assoc:
+              abort ();
+
+            case precedence_assoc:
+              break;
+
+            case right_assoc:
+              log_resolution (redrule, i, right_resolution);
+              flush_reduce (lookahead_tokens, i);
+              break;
+
+            case left_assoc:
+              log_resolution (redrule, i, left_resolution);
+              flush_shift (s, i);
+              break;
+
+            case non_assoc:
+              log_resolution (redrule, i, nonassoc_resolution);
+              flush_shift (s, i);
+              flush_reduce (lookahead_tokens, i);
+              /* Record an explicit error for this token.  */
+              errors[(*nerrs)++] = symbols[i];
+              break;
+            }
       }
-
-  /* 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);
 }
 
 
+/*-------------------------------------------------------------------.
+| Solve the S/R conflicts of state S using the                       |
+| precedence/associativity, and flag it inconsistent if it still has |
+| conflicts.  ERRORS can be used as storage to compute the list of   |
+| lookahead tokens on which S raises a syntax error (%nonassoc).     |
+`-------------------------------------------------------------------*/
+
 static void
-set_conflicts (state_t *state)
+set_conflicts (state *s, symbol **errors)
 {
   int i;
-  shifts *shiftp;
+  transitions *trans = s->transitions;
+  reductions *reds = s->reductions;
+  int nerrs = 0;
 
-  if (state->consistent)
+  if (s->consistent)
     return;
 
-  bitset_zero (lookaheadset);
+  bitset_zero (lookahead_set);
 
-  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));
+  FOR_EACH_SHIFT (trans, i)
+    bitset_set (lookahead_set, TRANSITION_SYMBOL (trans, i));
 
   /* Loop over all rules which require lookahead in this state.  First
      check for shift-reduce conflict, and try to resolve using
-     precedence */
-  for (i = 0; i < state->nlookaheads; ++i)
-    if (LArule[state->lookaheadsp + i]->prec
-       && LArule[state->lookaheadsp + i]->prec->prec
-       && !bitset_disjoint_p (LA[state->lookaheadsp + i], lookaheadset))
-      {
-       resolve_sr_conflict (state, state->lookaheadsp + i);
-       break;
-      }
+     precedence.  */
+  for (i = 0; i < reds->num; ++i)
+    if (reds->rules[i]->prec && reds->rules[i]->prec->prec
+        && !bitset_disjoint_p (reds->lookahead_tokens[i], lookahead_set))
+      resolve_sr_conflict (s, i, errors, &nerrs);
+
+  if (nerrs)
+    {
+      /* Some tokens have been explicitly made errors.  Allocate a
+         permanent errs structure for this state, to record them.  */
+      state_errs_set (s, nerrs, errors);
+    }
+  if (obstack_object_size (&solved_conflicts_obstack))
+    s->solved_conflicts = obstack_finish0 (&solved_conflicts_obstack);
+  if (obstack_object_size (&solved_conflicts_xml_obstack))
+    s->solved_conflicts_xml = obstack_finish0 (&solved_conflicts_xml_obstack);
 
   /* Loop over all rules which require lookahead in this state.  Check
      for conflicts not resolved above.  */
-  for (i = 0; i < state->nlookaheads; ++i)
+  for (i = 0; i < reds->num; ++i)
     {
-      if (!bitset_disjoint_p (LA[state->lookaheadsp + i], lookaheadset))
-       conflicts[state->number] = 1;
-
-      bitset_or (lookaheadset, lookaheadset, LA[state->lookaheadsp + i]);
+      if (!bitset_disjoint_p (reds->lookahead_tokens[i], lookahead_set))
+        conflicts[s->number] = 1;
+      bitset_or (lookahead_set, lookahead_set, reds->lookahead_tokens[i]);
     }
 }
 
+
+/*----------------------------------------------------------------.
+| Solve all the S/R conflicts using the precedence/associativity, |
+| and flag as inconsistent the states that still have conflicts.  |
+`----------------------------------------------------------------*/
+
 void
-solve_conflicts (void)
+conflicts_solve (void)
 {
-  size_t i;
+  state_number i;
+  /* List of lookahead tokens on which we explicitly raise a syntax error.  */
+  symbol **errors = xnmalloc (ntokens + 1, sizeof *errors);
 
-  conflicts = XCALLOC (char, nstates);
-  shiftset = bitset_create (ntokens, BITSET_FIXED);
-  lookaheadset = bitset_create (ntokens, BITSET_FIXED);
+  conflicts = xcalloc (nstates, sizeof *conflicts);
+  shift_set = bitset_create (ntokens, BITSET_FIXED);
+  lookahead_set = bitset_create (ntokens, BITSET_FIXED);
+  obstack_init (&solved_conflicts_obstack);
+  obstack_init (&solved_conflicts_xml_obstack);
 
   for (i = 0; i < nstates; i++)
-    set_conflicts (states[i]);
+    {
+      set_conflicts (states[i], errors);
+
+      /* For uniformity of the code, make sure all the states have a valid
+         `errs' member.  */
+      if (!states[i]->errs)
+        states[i]->errs = errs_new (0, 0);
+    }
+
+  free (errors);
+}
+
+
+void
+conflicts_update_state_numbers (state_number old_to_new[],
+                                state_number nstates_old)
+{
+  state_number i;
+  for (i = 0; i < nstates_old; ++i)
+    if (old_to_new[i] != nstates_old)
+      conflicts[old_to_new[i]] = conflicts[i];
 }
 
 
@@ -212,97 +422,86 @@ solve_conflicts (void)
 | Count the number of shift/reduce conflicts.  |
 `---------------------------------------------*/
 
-static int
-count_sr_conflicts (state_t *state)
+static size_t
+count_state_sr_conflicts (state *s)
 {
   int i;
-  int src_count = 0;
-  shifts *shiftp = state->shifts;
+  transitions *trans = s->transitions;
+  reductions *reds = s->reductions;
 
-  if (!shiftp)
+  if (!trans)
     return 0;
 
-  bitset_zero (lookaheadset);
-  bitset_zero (shiftset);
+  bitset_zero (lookahead_set);
+  bitset_zero (shift_set);
 
-  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));
+  FOR_EACH_SHIFT (trans, i)
+    bitset_set (shift_set, TRANSITION_SYMBOL (trans, i));
 
-  for (i = 0; i < state->nlookaheads; ++i)
-    bitset_or (lookaheadset, lookaheadset, LA[state->lookaheadsp + i]);
+  for (i = 0; i < reds->num; ++i)
+    bitset_or (lookahead_set, lookahead_set, reds->lookahead_tokens[i]);
 
-  bitset_and (lookaheadset, lookaheadset, shiftset);
+  bitset_and (lookahead_set, lookahead_set, shift_set);
 
-  src_count = bitset_count (lookaheadset);
+  return bitset_count (lookahead_set);
+}
+
+/*---------------------------------------------.
+| The total number of shift/reduce conflicts.  |
+`---------------------------------------------*/
+
+static size_t
+count_sr_conflicts (void)
+{
+  size_t res = 0;
+  state_number i;
 
-  return src_count;
+  /* Conflicts by state.  */
+  for (i = 0; i < nstates; i++)
+    if (conflicts[i])
+      res += count_state_sr_conflicts (states[i]);
+  return res;
 }
 
 
-/*----------------------------------------------.
-| Count the number of reduce/reduce conflicts.  |
-`----------------------------------------------*/
 
-static int
-count_rr_conflicts (state_t *state)
+/*----------------------------------------------------------------.
+| 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 size_t
+count_state_rr_conflicts (state *s, bool one_per_token)
 {
   int i;
-  int rrc_count = 0;
-
-  if (state->nlookaheads < 2)
-    return 0;
+  reductions *reds = s->reductions;
+  size_t res = 0;
 
   for (i = 0; i < ntokens; i++)
     {
       int count = 0;
       int j;
-      for (j = 0; j < state->nlookaheads; ++j)
-       if (bitset_test (LA[state->lookaheadsp + j], i))
-         count++;
-
+      for (j = 0; j < reds->num; ++j)
+        count += bitset_test (reds->lookahead_tokens[j], i);
       if (count >= 2)
-       rrc_count++;
+        res += one_per_token ? 1 : count-1;
     }
 
-  return rrc_count;
+  return res;
 }
 
-/*--------------------------------------------------------------.
-| Return a human readable string which reports shift/reduce and |
-| reduce/reduce conflict numbers (SRC_NUM, RRC_NUM).            |
-`--------------------------------------------------------------*/
-
-static const char *
-conflict_report (int src_num, int rrc_num)
+static size_t
+count_rr_conflicts (bool one_per_token)
 {
-  static char res[4096];
-  char *cp = res;
-
-  if (src_num >= 1)
-    {
-      sprintf (cp, ngettext ("%d shift/reduce conflict",
-                            "%d shift/reduce conflicts", src_num), src_num);
-      cp += strlen (cp);
-    }
-
-  if (src_num > 0 && rrc_num > 0)
-    {
-      sprintf (cp, " %s ", _("and"));
-      cp += strlen (cp);
-    }
-
-  if (rrc_num >= 1)
-    {
-      sprintf (cp, ngettext ("%d reduce/reduce conflict",
-                            "%d reduce/reduce conflicts", rrc_num), rrc_num);
-      cp += strlen (cp);
-    }
-
-  *cp++ = '.';
-  *cp++ = '\n';
-  *cp++ = '\0';
+  size_t res = 0;
+  state_number i;
 
+  /* Conflicts by state.  */
+  for (i = 0; i < nstates; i++)
+    if (conflicts[i])
+      res += count_state_rr_conflicts (states[i], one_per_token);
   return res;
 }
 
@@ -314,20 +513,44 @@ conflict_report (int src_num, int rrc_num)
 void
 conflicts_output (FILE *out)
 {
-  bool printed_sth = FALSE;
-  size_t i;
+  bool printed_sth = false;
+  state_number i;
   for (i = 0; i < nstates; i++)
-    if (conflicts[i])
-      {
-       fprintf (out, _("State %d contains "), i);
-       fputs (conflict_report (count_sr_conflicts (states[i]),
-                               count_rr_conflicts (states[i])), out);
-       printed_sth = TRUE;
-      }
+    {
+      state *s = states[i];
+      if (conflicts[i])
+        {
+          int src = count_state_sr_conflicts (s);
+          int rrc = count_state_rr_conflicts (s, true);
+          fprintf (out, _("State %d "), i);
+          if (src && rrc)
+            fprintf (out,
+                     _("conflicts: %d shift/reduce, %d reduce/reduce\n"),
+                     src, rrc);
+          else if (src)
+            fprintf (out, _("conflicts: %d shift/reduce\n"), src);
+          else if (rrc)
+            fprintf (out, _("conflicts: %d reduce/reduce\n"), rrc);
+          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)
+{
+  return count_sr_conflicts () + count_rr_conflicts (false);
+}
+
 
 /*------------------------------------------.
 | Reporting the total number of conflicts.  |
@@ -336,66 +559,66 @@ conflicts_output (FILE *out)
 void
 conflicts_print (void)
 {
-  size_t 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.  */
-  for (i = 0; i < nstates; i++)
-    if (conflicts[i])
-      {
-       src_total += count_sr_conflicts (states[i]);
-       rrc_total += count_rr_conflicts (states[i]);
-      }
-
-  src_ok = src_total == (expected_conflicts == -1 ? 0 : expected_conflicts);
-
-  /* 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;
-
-  /* Report the total number of conflicts on STDERR.  */
-  if (yacc_flag)
-    {
-      /* 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);
-    }
-  else
+  if (! glr_parser && expected_rr_conflicts != -1)
     {
-      fprintf (stderr, _("%s contains "), infile);
-      fputs (conflict_report (src_total, rrc_total), stderr);
+      complain (NULL, Wother, _("%%expect-rr applies only to GLR parsers"));
+      expected_rr_conflicts = -1;
     }
 
-  if (expected_conflicts != -1 && !src_ok)
-    {
-      complain_message_count++;
-      fprintf (stderr, ngettext ("expected %d shift/reduce conflict\n",
-                                "expected %d shift/reduce conflicts\n",
-                                expected_conflicts),
-              expected_conflicts);
-    }
+  /* Screams for factoring, but almost useless because of the
+     different strings to translate.  */
+  {
+    int total = count_sr_conflicts ();
+    // If %expect is not used, but %expect-rr is, then expect 0 sr.
+    int expected =
+      (expected_sr_conflicts == -1 && expected_rr_conflicts != -1)
+      ? 0
+      : expected_sr_conflicts;
+    if (expected != -1)
+      {
+        if (expected != total)
+          complain (NULL, complaint,
+                    _("shift/reduce conflicts: %d found, %d expected"),
+                    total, expected);
+      }
+    else if (total)
+      complain (NULL, Wconflicts_sr,
+                ngettext ("%d shift/reduce conflict",
+                          "%d shift/reduce conflicts",
+                          total),
+                total);
+  }
+
+  {
+    int total = count_rr_conflicts (true);
+    // If %expect-rr is not used, but %expect is, then expect 0 rr.
+    int expected =
+      (expected_rr_conflicts == -1 && expected_sr_conflicts != -1)
+      ? 0
+      : expected_rr_conflicts;
+    if (expected != -1)
+      {
+        if (expected != total)
+          complain (NULL, complaint,
+                    _("reduce/reduce conflicts: %d found, %d expected"),
+                    total, expected);
+      }
+    else if (total)
+      complain (NULL, Wconflicts_rr,
+                ngettext ("%d reduce/reduce conflict",
+                          "%d reduce/reduce conflicts",
+                          total),
+                total);
+  }
 }
 
 
 void
-free_conflicts (void)
+conflicts_free (void)
 {
-  XFREE (conflicts);
-  bitset_free (shiftset);
-  bitset_free (lookaheadset);
+  free (conflicts);
+  bitset_free (shift_set);
+  bitset_free (lookahead_set);
+  obstack_free (&solved_conflicts_obstack, NULL);
+  obstack_free (&solved_conflicts_xml_obstack, NULL);
 }