# Java skeleton for Bison -*- autoconf -*-
-# Copyright (C) 2007, 2008, 2009, 2010 Free Software Foundation, Inc.
+# Copyright (C) 2007-2011 Free Software Foundation, Inc.
# 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
m4_divert_push(0)dnl
@output(b4_parser_file_name@)@
b4_copyright([Skeleton implementation for Bison LALR(1) parsers in Java],
- [2007, 2008, 2009, 2010])
+ [2007-2011])
b4_percent_define_ifdef([package], [package b4_percent_define_get([package]);
])[/* First part of user declarations. */
private ]b4_location_type[ yylloc (YYStack rhs, int n)
{
if (n > 0)
- return new ]b4_location_type[ (rhs.locationAt (1).begin, rhs.locationAt (n).end);
+ return new ]b4_location_type[ (rhs.locationAt (n-1).begin, rhs.locationAt (0).end);
else
return new ]b4_location_type[ (rhs.locationAt (0).end);
}]])[
}
public final void pop () {
- height--;
+ pop (1);
}
public final void pop (int num) {
// Avoid memory leaks... garbage collection is a white lie!
if (num > 0) {
- java.util.Arrays.fill (valueStack, height - num + 1, height, null);
- ]b4_locations_if([[java.util.Arrays.fill (locStack, height - num + 1, height, null);]])[
+ java.util.Arrays.fill (valueStack, height - num + 1, height + 1, null);
+ ]b4_locations_if([[java.util.Arrays.fill (locStack, height - num + 1, height + 1, null);]])[
}
height -= num;
}
/* If not already recovering from an error, report this error. */
if (yyerrstatus_ == 0)
{
- ++yynerrs_;
- yyerror (]b4_locations_if([yylloc, ])[yysyntax_error (yystate, yytoken));
+ ++yynerrs_;
+ if (yychar == yyempty_)
+ yytoken = yyempty_;
+ yyerror (]b4_locations_if([yylloc, ])[yysyntax_error (yystate, yytoken));
}
]b4_locations_if([yyerrloc = yylloc;])[
{
if (errorVerbose)
{
- int yyn = yypact_[yystate];
- if (yypact_ninf_ < yyn && yyn <= yylast_)
+ /* There are many possibilities here to consider:
+ - Assume YYFAIL is not used. It's too flawed to consider.
+ See
+ <http://lists.gnu.org/archive/html/bison-patches/2009-12/msg00024.html>
+ for details. YYERROR is fine as it does not invoke this
+ function.
+ - If this state is a consistent state with a default action,
+ then the only way this function was invoked is if the
+ default action is an error action. In that case, don't
+ check for expected tokens because there are none.
+ - The only way there can be no lookahead present (in tok) is
+ if this state is a consistent state with a default action.
+ Thus, detecting the absence of a lookahead is sufficient to
+ determine that there is no unexpected or expected token to
+ report. In that case, just report a simple "syntax error".
+ - Don't assume there isn't a lookahead just because this
+ state is a consistent state with a default action. There
+ might have been a previous inconsistent state, consistent
+ state with a non-default action, or user semantic action
+ that manipulated yychar. (However, yychar is currently out
+ of scope during semantic actions.)
+ - Of course, the expected token list depends on states to
+ have correct lookahead information, and it depends on the
+ parser not to perform extra reductions after fetching a
+ lookahead from the scanner and before detecting a syntax
+ error. Thus, state merging (from LALR or IELR) and default
+ reductions corrupt the expected token list. However, the
+ list is correct for canonical LR with one exception: it
+ will still contain any token that will not be accepted due
+ to an error action in a later state.
+ */
+ if (tok != yyempty_)
{
- StringBuffer res;
-
+ // FIXME: This method of building the message is not compatible
+ // with internationalization.
+ StringBuffer res =
+ new StringBuffer ("syntax error, unexpected ");
+ res.append (yytnamerr_ (yytname_[tok]));
+ int yyn = yypact_[yystate];
+ if (!yy_pact_value_is_default_ (yyn))
+ {
/* Start YYX at -YYN if negative to avoid negative
indexes in YYCHECK. In other words, skip the first
-YYN actions for this state because they are default
actions. */
int yyxbegin = yyn < 0 ? -yyn : 0;
-
/* Stay within bounds of both yycheck and yytname. */
int yychecklim = yylast_ - yyn + 1;
int yyxend = yychecklim < yyntokens_ ? yychecklim : yyntokens_;
if (yycheck_[x + yyn] == x && x != yyterror_
&& !yy_table_value_is_error_ (yytable_[x + yyn]))
++count;
-
- // FIXME: This method of building the message is not compatible
- // with internationalization.
- res = new StringBuffer ("syntax error, unexpected ");
- res.append (yytnamerr_ (yytname_[tok]));
if (count < 5)
{
count = 0;
res.append (yytnamerr_ (yytname_[x]));
}
}
+ }
return res.toString ();
}
}
projects / bison.git / blobdiff