comment changes

[bison.git] / src / reader.c

diff --git a/src/reader.c b/src/reader.c
index 0422d2046ed4b33a486ed1f2f813c6e3d1bc5286..95c595ed4e0003aca48655e5097448260371040b 100644 (file)
--- a/src/reader.c
+++ b/src/reader.c
@@ -321,7 +321,7 @@ grammar_rule_check (const symbol_list *r)
         bool midrule_warning = false;
         if (!l->action_props.is_value_used
             && symbol_should_be_used (l, &midrule_warning)
-            /* The default action, $$ = $1, `uses' both.  */
+            /* The default action, $$ = $1, 'uses' both.  */
             && (r->action_props.code || (n != 0 && n != 1)))
           {
             warnings warn_flag = midrule_warning ? Wmidrule_values : Wother;
@@ -442,8 +442,10 @@ grammar_current_rule_prec_set (symbol *precsym, location loc)
      token.  */
   symbol_class_set (precsym, token_sym, loc, false);
   if (current_rule->ruleprec)
-    complain (&loc, complaint, _("only one %s allowed per rule"), "%prec");
-  current_rule->ruleprec = precsym;
+    duplicate_directive ("%prec",
+                         current_rule->ruleprec->location, loc);
+  else
+    current_rule->ruleprec = precsym;
 }
 
 /* Set %empty for the current rule. */
@@ -451,8 +453,13 @@ grammar_current_rule_prec_set (symbol *precsym, location loc)
 void
 grammar_current_rule_empty_set (location loc)
 {
+  /* If %empty is used and -Wno-empty-rule is not, then enable
+     -Wempty-rule.  */
+  if (warning_is_unset (Wempty_rule))
+    warning_argmatch ("empty-rule", 0, 0);
   if (current_rule->percent_empty_loc.start.file)
-    complain (&loc, complaint, _("only one %s allowed per rule"), "%empty");
+    duplicate_directive ("%empty",
+                         current_rule->percent_empty_loc, loc);
   else
     current_rule->percent_empty_loc = loc;
 }
@@ -469,8 +476,13 @@ grammar_current_rule_dprec_set (int dprec, location loc)
     complain (&loc, complaint, _("%s must be followed by positive number"),
               "%dprec");
   else if (current_rule->dprec != 0)
-    complain (&loc, complaint, _("only one %s allowed per rule"), "%dprec");
-  current_rule->dprec = dprec;
+    duplicate_directive ("%dprec",
+                         current_rule->dprec_location, loc);
+  else
+    {
+      current_rule->dprec = dprec;
+      current_rule->dprec_location = loc;
+    }
 }
 
 /* Attach a merge function NAME with argument type TYPE to current
@@ -483,9 +495,13 @@ grammar_current_rule_merge_set (uniqstr name, location loc)
     complain (&loc, Wother, _("%s affects only GLR parsers"),
               "%merge");
   if (current_rule->merger != 0)
-    complain (&loc, complaint, _("only one %s allowed per rule"), "%merge");
-  current_rule->merger = get_merge_function (name);
-  current_rule->merger_declaration_location = loc;
+    duplicate_directive ("%merge",
+                         current_rule->merger_declaration_location, loc);
+  else
+    {
+      current_rule->merger = get_merge_function (name);
+      current_rule->merger_declaration_location = loc;
+    }
 }
 
 /* Attach SYM to the current rule.  If needed, move the previous
@@ -500,7 +516,7 @@ grammar_current_rule_symbol_append (symbol *sym, location loc,
     grammar_midrule_action ();
   p = grammar_symbol_append (sym, loc);
   if (name)
-    assign_named_ref(p, name);
+    assign_named_ref (p, name);
   if (sym->status == undeclared || sym->status == used)
     sym->status = needed;
 }
@@ -558,7 +574,7 @@ packgram (void)
       rules[ruleno].action_location = p->action_props.location;
       rules[ruleno].is_predicate = p->action_props.is_predicate;
 
-      /* If the midrule's $$ is set or its $n is used, remove the `$' from the
+      /* If the midrule's $$ is set or its $n is used, remove the '$' from the
          symbol name so that it's a user-defined symbol so that the default
          %destructor and %printer apply.  */
       if (p->midrule_parent_rule
@@ -760,11 +776,11 @@ check_and_convert_grammar (void)
      action type checking.
 
      Before invoking grammar_rule_check (in packgram below) on any rule, make
-     sure all actions have already been scanned in order to set `used' flags.
+     sure all actions have already been scanned in order to set 'used' flags.
      Otherwise, checking that a midrule's $$ should be set will not always work
      properly because the check must forward-reference the midrule's parent
-     rule.  For the same reason, all the `used' flags must be set before
-     checking whether to remove `$' from any midrule symbol name (also in
+     rule.  For the same reason, all the 'used' flags must be set before
+     checking whether to remove '$' from any midrule symbol name (also in
      packgram).  */
   {
     symbol_list *sym;