freebsd-skq/contrib/byacc/test/err_inherit2.y
bapt 380a6c91bc Update to byacc 20140409
Among all the modifications, this new byacc also solves a 14 year old bug [1]

PR:		bin/23254 [1]
Submitted by:	marka@nominum.com [1]
MFC after:	3 weeks
2014-04-23 05:57:45 +00:00

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1.4 KiB
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%{
#include <stdlib.h>
typedef enum {cGLOBAL, cLOCAL} class;
typedef enum {tREAL, tINTEGER} type;
typedef char * name;
struct symbol { class c; type t; name id; };
typedef struct symbol symbol;
struct namelist { symbol *s; struct namelist *next; };
typedef struct namelist namelist;
extern symbol *mksymbol(type t, class c, name id);
#ifdef YYBISON
#define YYLEX_DECL() yylex(void)
#define YYERROR_DECL() yyerror(const char *s)
#endif
%}
%token <cval> GLOBAL LOCAL
%token <tval> REAL INTEGER
%token <id> NAME
%type <nlist> declaration namelist(<cval>, <tval>) locnamelist(<tval>)
%type <cval> class
%type <tval> type
%destructor {
namelist *p = $$;
while (p != NULL)
{ namelist *pp = p;
p = p->next;
free(pp->s); free(pp);
}
} <nlist>
%union
{
class cval;
type tval;
namelist * nlist;
name id;
}
%start declaration
%%
declaration: class type namelist($1, $2)
{ $$ = $3; }
| type locnamelist($1)
{ $$ = $2; }
;
class : GLOBAL { $$ = cGLOBAL; }
| LOCAL { $$ = cLOCAL; }
;
type : REAL { $$ = tREAL; }
| INTEGER { $$ = tINTEGER; }
;
namelist($<tval>c, $t, extra): namelist NAME
{ $$->s = mksymbol($<tval>t, $<cval>c, $2);
$$->next = $1;
}
| NAME
{ $$->s = mksymbol($t, $c, $1);
$$->next = NULL;
}
;
locnamelist($t): namelist(cLOCAL, $t)
{ $$ = $1; }
;
%%
extern int YYLEX_DECL();
extern void YYERROR_DECL();