Fix %error-verbose for conflicts resolved by %nonassoc.

* NEWS (2.5): Document.
* data/glr.c (yyreportSyntaxError): Fix this by checking
yyis_table_ninf.
* data/yacc.c (yysyntax_error): Likewise.
* data/lalr1.cc (yysyntax_error_): Fix this by checking
yytable_ninf_.
* data/lalr1.java (yysyntax_error): Likewise.
* tests/conflicts.at (%nonassoc and eof): Update expected output
and remove FIXME.

ChangeLog

@@ -1,3 +1,16 @@
+2009-08-25  Joel E. Denny  <jdenny@clemson.edu>
+
+	Fix %error-verbose for conflicts resolved by %nonassoc.
+	* NEWS (2.5): Document.
+	* data/glr.c (yyreportSyntaxError): Fix this by checking
+	yyis_table_ninf.
+	* data/yacc.c (yysyntax_error): Likewise.
+	* data/lalr1.cc (yysyntax_error_): Fix this by checking
+	yytable_ninf_.
+	* data/lalr1.java (yysyntax_error): Likewise.
+	* tests/conflicts.at (%nonassoc and eof): Update expected output
+	and remove FIXME.
+
 2009-08-25  Joel E. Denny  <jdenny@clemson.edu>
 
 	Some code and documentation improvements.

NEWS

@@ -146,6 +146,15 @@ Bison News
   Bison now warns when a character literal is not of length one.  In
   some future release, Bison will report an error instead.
 
+** Verbose error messages fixed for nonassociative tokens.
+
+  When %error-verbose is specified, syntax error messages produced by
+  the generated parser include the unexpected token as well as a list of
+  expected tokens.  Previously, this list erroneously included tokens
+  that would actually induce a syntax error because conflicts for them
+  were resolved with %nonassoc.  Such tokens are now properly omitted
+  from the list.
+
 * Changes in version 2.4.2 (????-??-??):
 
 ** Detection of GNU M4 1.4.6 or newer during configure is improved.

data/glr.c

@@ -2060,7 +2060,8 @@ yyreportSyntaxError (yyGLRStack* yystackp]b4_user_formals[)
 	  yyarg[yycount++] = yytokenName (yytoken);
 
 	  for (yyx = yyxbegin; yyx < yyxend; ++yyx)
-	    if (yycheck[yyx + yyn] == yyx && yyx != YYTERROR)
+	    if (yycheck[yyx + yyn] == yyx && yyx != YYTERROR
+		&& !yyis_table_ninf (yytable[yyx + yyn]))
 	      {
 		if (yycount == YYERROR_VERBOSE_ARGS_MAXIMUM)
 		  {

data/lalr1.cc

@@ -971,7 +971,8 @@ b4_error_verbose_if([state_type yystate, int yytoken],
         char const *yyarg[YYERROR_VERBOSE_ARGS_MAXIMUM];
         yyarg[yycount++] = yytname_[yytoken];
 	for (int yyx = yyxbegin; yyx < yyxend; ++yyx)
-	  if (yycheck_[yyx + yyn] == yyx && yyx != yyterror_)
+	  if (yycheck_[yyx + yyn] == yyx && yyx != yyterror_
+	      && yytable_[yyx + yyn] != yytable_ninf_)
           {
             if (yycount == YYERROR_VERBOSE_ARGS_MAXIMUM)
             {

data/lalr1.java

@@ -744,7 +744,8 @@ m4_popdef([b4_at_dollar])])dnl
             int yyxend = yychecklim < yyntokens_ ? yychecklim : yyntokens_;
             int count = 0;
             for (int x = yyxbegin; x < yyxend; ++x)
-              if (yycheck_[x + yyn] == x && x != yyterror_)
+              if (yycheck_[x + yyn] == x && x != yyterror_
+                  && yycheck_[x + yyn] != yytable_ninf_)
                 ++count;
 
             // FIXME: This method of building the message is not compatible
@@ -755,7 +756,8 @@ m4_popdef([b4_at_dollar])])dnl
               {
                 count = 0;
                 for (int x = yyxbegin; x < yyxend; ++x)
-                  if (yycheck_[x + yyn] == x && x != yyterror_)
+                  if (yycheck_[x + yyn] == x && x != yyterror_
+                      && yycheck_[x + yyn] != yytable_ninf_)
                     {
                       res.append (count++ == 0 ? ", expecting " : " or ");
                       res.append (yytnamerr_ (yytname_[x]));

data/yacc.c

@@ -869,7 +869,8 @@ yysyntax_error (char *yyresult, int yystate, int yytoken)
       yyarg[yycount++] = yytname[yytoken];
 
       for (yyx = yyxbegin; yyx < yyxend; ++yyx)
-	if (yycheck[yyx + yyn] == yyx && yyx != YYTERROR)
+	if (yycheck[yyx + yyn] == yyx && yyx != YYTERROR
+	    && !yyis_table_ninf (yytable[yyx + yyn]))
 	  {
 	    if (yycount == YYERROR_VERBOSE_ARGS_MAXIMUM)
 	      {

src/parse-gram.h

@@ -1,4 +1,4 @@
-/* A Bison parser, made by GNU Bison 2.4.343-83ea.  */
+/* A Bison parser, made by GNU Bison 2.4.386-e6c849.  */
 
 /* Interface for Bison's Yacc-like parsers in C
 
@@ -157,7 +157,7 @@
 #if ! defined YYSTYPE && ! defined YYSTYPE_IS_DECLARED
 typedef union YYSTYPE
 {
-/* Line 1600 of yacc.c  */
+/* Line 1608 of yacc.c  */
 #line 94 "parse-gram.y"
 
   symbol *symbol;
@@ -171,8 +171,8 @@ typedef union YYSTYPE
   named_ref *named_ref;
 
 
-/* Line 1600 of yacc.c  */
+/* Line 1608 of yacc.c  */
-#line 176 "../master/src/parse-gram.h"
+#line 176 "src/parse-gram.h"
 } YYSTYPE;
 # define YYSTYPE_IS_TRIVIAL 1
 # define yystype YYSTYPE /* obsolescent; will be withdrawn */

tests/conflicts.at

@@ -99,20 +99,17 @@ AT_BISON_CHECK([-o input.c input.y])
 AT_COMPILE([input])
 
 AT_PARSER_CHECK([./input '0<0'])
-# FIXME: This is an actual bug, but a new one, in the sense that
-# no one has ever spotted it!  The messages are *wrong*: there should
-# be nothing there, it should be expected eof.
 AT_PARSER_CHECK([./input '0<0<0'], [1], [],
-         [syntax error, unexpected '<', expecting '<' or '>'
+         [syntax error, unexpected '<'
 ])
 
 AT_PARSER_CHECK([./input '0>0'])
 AT_PARSER_CHECK([./input '0>0>0'], [1], [],
-         [syntax error, unexpected '>', expecting '<' or '>'
+         [syntax error, unexpected '>'
 ])
 
 AT_PARSER_CHECK([./input '0<0>0'], [1], [],
-         [syntax error, unexpected '>', expecting '<' or '>'
+         [syntax error, unexpected '>'
 ])
 
 AT_CLEANUP