doing locations. This is more consistent with yacc.c, and it
works around the following bug reports:
http://mail.gnu.org/pipermail/bug-bison/2002-October/001748.html
http://mail.gnu.org/pipermail/bug-bison/2002-October/001764.html
http://mail.gnu.org/pipermail/bug-bison/2002-October/001769.html
#ifndef YYLTYPE
typedef struct yyltype
{
#ifndef YYLTYPE
typedef struct yyltype
{
int first_line;
int first_column;
int last_line;
int first_line;
int first_column;
int last_line;
} yyltype;
# define YYLTYPE ]b4_location_type[
# define YYLTYPE_IS_TRIVIAL 1
} yyltype;
# define YYLTYPE ]b4_location_type[
# define YYLTYPE_IS_TRIVIAL 1