mirror of
https://git.savannah.gnu.org/git/bison.git
synced 2026-03-09 12:23:04 +00:00
f3d33c3613
This revealed a number of things I had not realized:
- the Java location tracking was aliasing the same pair of positions
for all the symbols (see previous commit).
- in impure parsers, it's quite easy to use incorrect locations for
diagnostics, since yyerror uses yylloc, which is the location of the
lookahead, not that of the current lhs. So we need something like
{
YYLTYPE old_yylloc = yylloc;
yylloc = @$;
yyerror (]AT_PARAM_IF([result, count, nerrs, ])[buf);
yylloc = old_yylloc;
}
Maybe we should do that little yylloc dance in the skeleton instead
of leaving it to the user? It might be costly... But that's only
for users of the impure parsers, which are asking for trouble
anyway.
- in glr.cc invoking yyerror is somewhat cumbersome: the C++ interface
is not available as we are in yyparse (which in C), and yyerror is
used by glr.cc itself to bind it to the user's parser::error. If we
call yyerror, we need:
yyerror (]AT_LOCATION_IF([[&@$, ]])[yyparser, ]AT_PARAM_IF([result, count, nerrs, ])[msg);
However calling yy::parser::error is easier, once we know that the
current parser object is available as 'yyparser'. Which also saves
us from having to pass the parse-params ourselves:
yyparser.error (]AT_LOCATION_IF([[@$, ]])[msg);
* tests/calc.at: Invoke yyerror by hand, instead of using fprintf etc.
Adjust expectations.