dave@sq.UUCP (05/13/87)
Is this a bug in lex?
On the AT&T 3B2 Sys V and Sun 3/180 Sun Unix 3.0
and lex being used with yacc. Lex busts when used with a token
defined in yacc as "p" "m" or "c".
For example cut up the following.
********* yacc file (foo) **********
%token p
%%
null :
;
%%
#include "lex.yy.c"
main()
{
yyparse();
}
********** lex file (bar)************
%%
********** type the following *******
yacc foo
lex bar
cc -o blah y.tab.c -ll
*****you should get something like***
"./lex.yy.c", line 232: syntax error at or near constant 257
"./lex.yy.c", line 233: syntax error at or near constant 257
"./lex.yy.c", line 236: illegal indirection
"./lex.yy.c", line 238: illegal lhs of assignment operator
"./lex.yy.c", line 238: illegal indirection
********** offensive code follows ***
********** from /usr/lib/lex/ncform *
yyback(p, m)
int *p;
{
if (p==0) return(0);
while (*p)
{
if (*p++ == m)
return(1);
}
return(0);
}
/* the following are only used in the lex library */
yyinput(){
return(input());
}
yyoutput(c)
int c; {
output(c);
}
yyunput(c)
int c; {
unput(c);
}
*********
Shouldn't these declarations use obscure variable names like yym yyp yyc ?
David R. Seaman
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