From mboxrd@z Thu Jan 1 00:00:00 1970 Content-type: multipart/alternative; boundary=Apple-Mail-D7434540-E740-40AC-8464-6B207B7D36DC MIME-version: 1.0 (1.0) From: Brantley Coile In-reply-to: <79F2255E-5E76-43E8-83B3-0DFB2CD34AC7@bitblocks.com> Date: Thu, 26 Nov 2015 06:22:45 -0500 Content-transfer-encoding: 7bit Message-id: <3175949A-26D0-4C4A-BB7D-4E5A3EA7F8B7@me.com> References: <20151125160347.GN20646@sigint.cs.purdue.edu> <79F2255E-5E76-43E8-83B3-0DFB2CD34AC7@bitblocks.com> To: Fans of the OS Plan 9 from Bell Labs <9fans@9fans.net> Subject: Re: [9fans] Undefined Behaviour in C Topicbox-Message-UUID: 779db0b2-ead9-11e9-9d60-3106f5b1d025 --Apple-Mail-D7434540-E740-40AC-8464-6B207B7D36DC Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: quoted-printable Hi Bakul. Long time since our Bay Area plan 9 hacking sessions. I've avoide= d the valley all together for a year and a half now. Not quite long enough y= et.=20 I thought the same thing, using ~0 for nil, but realized two things. First, t= hat's a valid address on the PDP11 where the convention developed. It's the u= nibus space. Second, ~0 + member offest is still in page zero.=20 By the way, are there any structs more than 4K in Linux? Are there any in pl= an 9? Sent from my iPad > On Nov 26, 2015, at 2:27 AM, Bakul Shah wrote: >=20 > Using 0xfff...f instead of 0 for a null ptr might've been less "disgusting= "!=20 >=20 >> On Nov 25, 2015, at 6:04 PM, Prof Brucee wrote: >>=20 >> gcc is indeed a very sad tome. The mmap of 0 is disgusting. I like kenc. I= t just works. My behaviour this afternoon will be undefined but not as stupi= d as that of some programmers. >>=20 >>> On 26/11/2015 5:43 AM, "Brantley Coile" wrote: >>> Align it to column 7 and it looks like all the code I saw when I started= .=20 >>>=20 >>> iPhone email >>>=20 >>>> On Nov 25, 2015, at 12:13 PM, Ryan Gonzalez wrote: >>>>=20 >>>> Neither! It's what happens when you run sed 's/^\s*//' on your whole co= de base, yielding results like (from cmd/yacc.c): >>>>=20 >>>>=20 >>>> void >>>> setup(int argc, char *argv[]) >>>> { >>>> long c, t; >>>> int i, j, fd, lev, ty, ytab, *p; >>>> int vflag, dflag, stem; >>>> char actnm[8], *stemc, *s, dirbuf[128]; >>>> Biobuf *fout; >>>>=20 >>>> ytab =3D 0; >>>> vflag =3D 0; >>>> dflag =3D 0; >>>> stem =3D 0; >>>> stemc =3D "y"; >>>> foutput =3D 0; >>>> fdefine =3D 0; >>>> fdebug =3D 0; >>>> ARGBEGIN{ >>>> case 'v': >>>> case 'V': >>>> vflag++; >>>> break; >>>> case 'D': >>>> yydebug =3D ARGF(); >>>> break; >>>> case 'a': >>>> yyarg =3D 1; >>>> break; >>>> case 'd': >>>> dflag++; >>>> break; >>>> case 'l': >>>> yyline =3D 0; >>>> break; >>>> case 'o': >>>> ytab++; >>>> ytabc =3D ARGF(); >>>> break; >>>> case 's': >>>> stem++; >>>> stemc =3D ARGF(); >>>> break; >>>> case 'S': >>>> parser =3D PARSERS; >>>> break; >>>> default: >>>> error("illegal option: %c", ARGC()); >>>> }ARGEND >>>> openup(stemc, dflag, vflag, ytab, ytabc); >>>> fout =3D dflag?fdefine:ftable; >>>> if(yyarg){ >>>> Bprint(ftable, "#define\tYYARG\t1\n\n"); >>>> } >>>> if((fd =3D mkstemp(ttempname)) >=3D 0){ >>>> tempname =3D ttempname; >>>> ftemp =3D Bfdopen(fd, OWRITE); >>>> } >>>> if((fd =3D mkstemp(tactname)) >=3D 0){ >>>> actname =3D tactname; >>>> faction =3D Bfdopen(fd, OWRITE); >>>> } >>>> if(ftemp =3D=3D 0 || faction =3D=3D 0) >>>> error("cannot open temp file"); >>>> if(argc < 1) >>>> error("no input file"); >>>> infile =3D argv[0]; >>>> if(infile[0] !=3D '/' && getwd(dirbuf, sizeof dirbuf)!=3Dnil){ >>>> i =3D strlen(infile)+1+strlen(dirbuf)+1+10; >>>> s =3D malloc(i); >>>> if(s !=3D nil){ >>>> snprint(s, i, "%s/%s", dirbuf, infile); >>>> cleanname(s); >>>> infile =3D s; >>>> } >>>> } >>>> finput =3D Bopen(infile, OREAD); >>>> if(finput =3D=3D 0) >>>> error("cannot open '%s'", argv[0]); >>>> cnamp =3D cnames; >>>>=20 >>>> defin(0, "$end"); >>>> extval =3D PRIVATE; /* tokens start in unicode 'private use' */= >>>> defin(0, "error"); >>>> defin(1, "$accept"); >>>> defin(0, "$unk"); >>>> mem =3D mem0; >>>> i =3D 0; >>>>=20 >>>> for(t =3D gettok(); t !=3D MARK && t !=3D ENDFILE;) >>>> switch(t) { >>>> case ';': >>>> t =3D gettok(); >>>> break; >>>>=20 >>>> case START: >>>> if(gettok() !=3D IDENTIFIER) >>>> error("bad %%start construction"); >>>> start =3D chfind(1, tokname); >>>> t =3D gettok(); >>>> continue; >>>>=20 >>>> case TYPEDEF: >>>> if(gettok() !=3D TYPENAME) >>>> error("bad syntax in %%type"); >>>> ty =3D numbval; >>>> for(;;) { >>>> t =3D gettok(); >>>> switch(t) { >>>> case IDENTIFIER: >>>> if((t=3Dchfind(1, tokname)) < NTBASE) { >>>> j =3D TYPE(toklev[t]); >>>> if(j !=3D 0 && j !=3D ty) >>>> error("type redeclaration of token %s", >>>> tokset[t].name); >>>> else >>>> SETTYPE(toklev[t], ty); >>>> } else { >>>> j =3D nontrst[t-NTBASE].value; >>>> if(j !=3D 0 && j !=3D ty) >>>> error("type redeclaration of nonterminal %s", >>>> nontrst[t-NTBASE].name ); >>>> else >>>> nontrst[t-NTBASE].value =3D ty; >>>> } >>>> case ',': >>>> continue; >>>> case ';': >>>> t =3D gettok(); >>>> default: >>>> break; >>>> } >>>> break; >>>> } >>>> continue; >>>>=20 >>>> case UNION: >>>> /* copy the union declaration to the output */ >>>> cpyunion(); >>>> t =3D gettok(); >>>> continue; >>>>=20 >>>> case LEFT: >>>> case BINARY: >>>> case RIGHT: >>>> i++; >>>>=20 >>>> case TERM: >>>> /* nonzero means new prec. and assoc. */ >>>> lev =3D t-TERM; >>>> ty =3D 0; >>>>=20 >>>> /* get identifiers so defined */ >>>> t =3D gettok(); >>>>=20 >>>> /* there is a type defined */ >>>> if(t =3D=3D TYPENAME) { >>>> ty =3D numbval; >>>> t =3D gettok(); >>>> } >>>> for(;;) { >>>> switch(t) { >>>> case ',': >>>> t =3D gettok(); >>>> continue; >>>>=20 >>>> case ';': >>>> break; >>>>=20 >>>> case IDENTIFIER: >>>> j =3D chfind(0, tokname); >>>> if(j >=3D NTBASE) >>>> error("%s defined earlier as nonterminal", tokname); >>>> if(lev) { >>>> if(ASSOC(toklev[j])) >>>> error("redeclaration of precedence of %s", tokname); >>>> SETASC(toklev[j], lev); >>>> SETPLEV(toklev[j], i); >>>> } >>>> if(ty) { >>>> if(TYPE(toklev[j])) >>>> error("redeclaration of type of %s", tokname); >>>> SETTYPE(toklev[j],ty); >>>> } >>>> t =3D gettok(); >>>> if(t =3D=3D NUMBER) { >>>> tokset[j].value =3D numbval; >>>> if(j < ndefout && j > 3) >>>> error("please define type number of %s earlier", >>>> tokset[j].name); >>>> t =3D gettok(); >>>> } >>>> continue; >>>> } >>>> break; >>>> } >>>> continue; >>>>=20 >>>> case LCURLY: >>>> defout(0); >>>> cpycode(); >>>> t =3D gettok(); >>>> continue; >>>>=20 >>>> default: >>>> error("syntax error"); >>>> } >>>> if(t =3D=3D ENDFILE) >>>> error("unexpected EOF before %%"); >>>>=20 >>>> /* t is MARK */ >>>> if(!yyarg) >>>> Bprint(ftable, "extern int yyerrflag;\n"); >>>> Bprint(ftable, "#ifndef YYMAXDEPTH\n"); >>>> Bprint(ftable, "#define YYMAXDEPTH 150\n"); >>>> Bprint(ftable, "#endif\n" ); >>>> if(!ntypes) { >>>> Bprint(ftable, "#ifndef YYSTYPE\n"); >>>> Bprint(ftable, "#define YYSTYPE int\n"); >>>> Bprint(ftable, "#endif\n"); >>>> } >>>> if(!yyarg){ >>>> Bprint(ftable, "YYSTYPE yylval;\n"); >>>> Bprint(ftable, "YYSTYPE yyval;\n"); >>>> }else{ >>>> if(dflag) >>>> Bprint(ftable, "#include \"%s.%s\"\n\n", stemc, FILED); >>>> Bprint(fout, "struct Yyarg {\n"); >>>> Bprint(fout, "\tint\tyynerrs;\n"); >>>> Bprint(fout, "\tint\tyyerrflag;\n"); >>>> Bprint(fout, "\tvoid*\targ;\n"); >>>> Bprint(fout, "\tYYSTYPE\tyyval;\n"); >>>> Bprint(fout, "\tYYSTYPE\tyylval;\n"); >>>> Bprint(fout, "};\n\n"); >>>> } >>>> prdptr[0] =3D mem; >>>>=20 >>>> /* added production */ >>>> *mem++ =3D NTBASE; >>>>=20 >>>> /* if start is 0, we will overwrite with the lhs of the first rule */ >>>> *mem++ =3D start; >>>> *mem++ =3D 1; >>>> *mem++ =3D 0; >>>> prdptr[1] =3D mem; >>>> while((t=3Dgettok()) =3D=3D LCURLY) >>>> cpycode(); >>>> if(t !=3D IDENTCOLON) >>>> error("bad syntax on first rule"); >>>>=20 >>>> if(!start) >>>> prdptr[0][1] =3D chfind(1, tokname); >>>>=20 >>>> /* read rules */ >>>> while(t !=3D MARK && t !=3D ENDFILE) { >>>> /* process a rule */ >>>> rlines[nprod] =3D lineno; >>>> if(t =3D=3D '|') >>>> *mem++ =3D *prdptr[nprod-1]; >>>> else >>>> if(t =3D=3D IDENTCOLON) { >>>> *mem =3D chfind(1, tokname); >>>> if(*mem < NTBASE) >>>> error("token illegal on LHS of grammar rule"); >>>> mem++; >>>> } else >>>> error("illegal rule: missing semicolon or | ?"); >>>> /* read rule body */ >>>> t =3D gettok(); >>>>=20 >>>> more_rule: >>>> while(t =3D=3D IDENTIFIER) { >>>> *mem =3D chfind(1, tokname); >>>> if(*mem < NTBASE) >>>> levprd[nprod] =3D toklev[*mem]; >>>> mem++; >>>> t =3D gettok(); >>>> } >>>> if(t =3D=3D PREC) { >>>> if(gettok() !=3D IDENTIFIER) >>>> error("illegal %%prec syntax"); >>>> j =3D chfind(2, tokname); >>>> if(j >=3D NTBASE) >>>> error("nonterminal %s illegal after %%prec", >>>> nontrst[j-NTBASE].name); >>>> levprd[nprod] =3D toklev[j]; >>>> t =3D gettok(); >>>> } >>>> if(t =3D=3D '=3D') { >>>> levprd[nprod] |=3D ACTFLAG; >>>> Bprint(faction, "\ncase %d:", nprod); >>>> cpyact(mem-prdptr[nprod]-1); >>>> Bprint(faction, " break;"); >>>> if((t=3Dgettok()) =3D=3D IDENTIFIER) { >>>>=20 >>>> /* action within rule... */ >>>> sprint(actnm, "$$%d", nprod); >>>>=20 >>>> /* make it a nonterminal */ >>>> j =3D chfind(1, actnm); >>>>=20 >>>> /* >>>> * the current rule will become rule number nprod+1 >>>> * move the contents down, and make room for the null >>>> */ >>>> for(p =3D mem; p >=3D prdptr[nprod]; --p) >>>> p[2] =3D *p; >>>> mem +=3D 2; >>>>=20 >>>> /* enter null production for action */ >>>> p =3D prdptr[nprod]; >>>> *p++ =3D j; >>>> *p++ =3D -nprod; >>>>=20 >>>> /* update the production information */ >>>> levprd[nprod+1] =3D levprd[nprod] & ~ACTFLAG; >>>> levprd[nprod] =3D ACTFLAG; >>>> if(++nprod >=3D NPROD) >>>> error("more than %d rules", NPROD); >>>> prdptr[nprod] =3D p; >>>>=20 >>>> /* make the action appear in the original rule */ >>>> *mem++ =3D j; >>>>=20 >>>> /* get some more of the rule */ >>>> goto more_rule; >>>> } >>>> } >>>>=20 >>>> while(t =3D=3D ';') >>>> t =3D gettok(); >>>> *mem++ =3D -nprod; >>>>=20 >>>> /* check that default action is reasonable */ >>>> if(ntypes && !(levprd[nprod]&ACTFLAG) && nontrst[*prdptr[nprod]-NTBASE]= .value) { >>>>=20 >>>> /* no explicit action, LHS has value */ >>>> int tempty; >>>>=20 >>>> tempty =3D prdptr[nprod][1]; >>>> if(tempty < 0) >>>> error("must return a value, since LHS has a type"); >>>> else >>>> if(tempty >=3D NTBASE) >>>> tempty =3D nontrst[tempty-NTBASE].value; >>>> else >>>> tempty =3D TYPE(toklev[tempty]); >>>> if(tempty !=3D nontrst[*prdptr[nprod]-NTBASE].value) >>>> error("default action causes potential type clash"); >>>> } >>>> nprod++; >>>> if(nprod >=3D NPROD) >>>> error("more than %d rules", NPROD); >>>> prdptr[nprod] =3D mem; >>>> levprd[nprod] =3D 0; >>>> } >>>>=20 >>>> /* end of all rules */ >>>> defout(1); >>>>=20 >>>> finact(); >>>> if(t =3D=3D MARK) { >>>> Bprint(ftable, "\n"); >>>> if(yyline) >>>> Bprint(ftable, "#line\t%d\t\"%s\"\n", lineno, infile); >>>> while((c=3DBgetrune(finput)) !=3D Beof) >>>> Bputrune(ftable, c); >>>> } >>>> Bterm(finput); >>>> } >>>>=20 >>>>=20 >>>>> On Wed, Nov 25, 2015 at 10:03 AM, wrot= e: >>>>> On Wed, Nov 25, 2015 at 09:25:55AM -0500, Brantley Coile wrote: >>>>> > unindented consequences >>>>>=20 >>>>> Is that a class of Python bugs or an awesome name for a Nerdcore band?= >>>>=20 >>>>=20 >>>>=20 >>>> --=20 >>>> Ryan >>>> [ERROR]: Your autotools build scripts are 200 lines longer than your pr= ogram. Something=E2=80=99s wrong. >>>> http://kirbyfan64.github.io/ --Apple-Mail-D7434540-E740-40AC-8464-6B207B7D36DC Content-Type: text/html; charset=utf-8 Content-Transfer-Encoding: quoted-printable
Hi Bakul.  Long time since our Ba= y Area plan 9 hacking sessions. I've avoided the valley all together for a y= ear and a half now. Not quite long enough yet. 

I thought the same thi= ng, using ~0 for nil, but realized two things. First, that's a valid address= on the PDP11 where the convention developed. It's the unibus space. Second,= ~0 + member offest is still in page zero. 

By the way, are there any s= tructs more than 4K in Linux? Are there any in plan 9?

Sent from my i= Pad

On Nov 26, 2015, at 2:27 AM, Bakul Shah <bakul@bitblocks.com> wrote:

Using 0xfff...f instead of 0 for a n= ull ptr might've been less "disgusting"! 

On Nov 25, 2015= , at 6:04 PM, Prof Brucee <prof.= brucee@gmail.com> wrote:

=

gcc is indeed a very sad tome. The mmap of 0 is disgusting. I= like kenc. It just works. My behaviour this afternoon will be undefined but= not as stupid as that of some programmers.

On 26/11/2015 5:43 AM, "Brantley Coile" <brantleycoile@me.com> wrote:
Align it to column 7 and it= looks like all the code I saw when I started. 

iPhone em= ail

On Nov 25, 2015, at 12:13 PM, Ryan Gonzalez <rymg19@gmail.com> wrote:<= br>
Neither! It's w= hat happens when you run sed 's/^\s*//' on your whole code base, yielding re= sults like (from cmd/yacc.c):


void
setup(int argc, char *argv[])
{
long c, t;
=
int i, j, fd, lev, ty, ytab, *p;
int vflag, dflag, stem;
char actnm[8], *stemc, *s, dirbuf[128];
Biobuf *fout;
<= div>
ytab =3D 0;
vflag =3D 0;
dflag =3D 0;=
stem =3D 0;
stemc =3D "y";
foutput =3D 0;
fdefine =3D 0;
fdebug =3D 0;
ARGBEGIN{
= case 'v':
case 'V':
vflag++;
break;
= case 'D':
yydebug =3D ARGF();
break;
case 'a':=
yyarg =3D 1;
break;
case 'd':
dflag= ++;
break;
case 'l':
yyline =3D 0;
b= reak;
case 'o':
ytab++;
ytabc =3D ARGF();
break;
case 's':
stem++;
stemc =3D ARGF(= );
break;
case 'S':
parser =3D PARSERS;
<= div>break;
default:
error("illegal option: %c", ARGC());=
}ARGEND
openup(stemc, dflag, vflag, ytab, ytabc);
=
fout =3D dflag?fdefine:ftable;
if(yyarg){
Bprint(ft= able, "#define\tYYARG\t1\n\n");
}
if((fd =3D mkstemp(tte= mpname)) >=3D 0){
tempname =3D ttempname;
ftemp =3D B= fdopen(fd, OWRITE);
}
if((fd =3D mkstemp(tactname)) >= =3D 0){
actname =3D tactname;
faction =3D Bfdopen(fd, OW= RITE);
}
if(ftemp =3D=3D 0 || faction =3D=3D 0)
error("cannot open temp file");
if(argc < 1)
error(= "no input file");
infile =3D argv[0];
if(infile[0] !=3D '= /' && getwd(dirbuf, sizeof dirbuf)!=3Dnil){
i =3D strlen(i= nfile)+1+strlen(dirbuf)+1+10;
s =3D malloc(i);
if(s !=3D= nil){
snprint(s, i, "%s/%s", dirbuf, infile);
cleanname= (s);
infile =3D s;
}
}
finput =3D Bo= pen(infile, OREAD);
if(finput =3D=3D 0)
error("cannot op= en '%s'", argv[0]);
cnamp =3D cnames;

def= in(0, "$end");
extval =3D PRIVATE; /* tokens start in unicode 'private use' */
defin(= 0, "error");
defin(1, "$accept");
defin(0, "$unk");
mem =3D mem0;
i =3D 0;

for(t =3D ge= ttok(); t !=3D MARK && t !=3D ENDFILE;)
switch(t) {
<= div>case ';':
t =3D gettok();
break;

case START:
if(gettok() !=3D IDENTIFIER)
error("ba= d %%start construction");
start =3D chfind(1, tokname);
= t =3D gettok();
continue;

case TYPEDEF:
if(gettok() !=3D TYPENAME)
error("bad syntax in %%type");=
ty =3D numbval;
for(;;) {
t =3D gettok();
switch(t) {
case IDENTIFIER:
if((t=3Dchfind(1, to= kname)) < NTBASE) {
j =3D TYPE(toklev[t]);
if(j !=3D 0= && j !=3D ty)
error("type redeclaration of token %s",
tokset[t].name);
else
SETTYPE(toklev[t], ty);
} else {
j =3D nontrst[t-NTBASE].value;
if(j !=3D= 0 && j !=3D ty)
error("type redeclaration of nonterminal %= s",
nontrst[t-NTBASE].name );
else
nontrst[t-N= TBASE].value =3D ty;
}
case ',':
continue;
case ';':
t =3D gettok();
default:
brea= k;
}
break;
}
continue;
case UNION:
/* copy the union declaration to the outp= ut */
cpyunion();
t =3D gettok();
continue;

case LEFT:
case BINARY:
case RIGH= T:
i++;

case TERM:
/* nonzero m= eans new prec. and assoc. */
lev =3D t-TERM;
ty =3D 0;

/* get identifiers so defined */
t =3D get= tok();

/* there is a type defined */
if(t= =3D=3D TYPENAME) {
ty =3D numbval;
t =3D gettok();
}
for(;;) {
switch(t) {
case ',':
<= div>t =3D gettok();
continue;

case ';':
break;

case IDENTIFIER:
j =3D ch= find(0, tokname);
if(j >=3D NTBASE)
error("%s defined= earlier as nonterminal", tokname);
if(lev) {
if(ASSOC(t= oklev[j]))
error("redeclaration of precedence of %s", tokname);
SETASC(toklev[j], lev);
SETPLEV(toklev[j], i);
}=
if(ty) {
if(TYPE(toklev[j]))
error("redeclara= tion of type of %s", tokname);
SETTYPE(toklev[j],ty);
}<= /div>
t =3D gettok();
if(t =3D=3D NUMBER) {
tokset[j= ].value =3D numbval;
if(j < ndefout && j > 3)
<= div>error("please define type number of %s earlier",
tokset[j].nam= e);
t =3D gettok();
}
continue;
}
break;
}
continue;

case= LCURLY:
defout(0);
cpycode();
t =3D gettok();=
continue;

default:
error("synt= ax error");
}
if(t =3D=3D ENDFILE)
error("unex= pected EOF before %%");

/* t is MARK */
i= f(!yyarg)
Bprint(ftable, "extern int yyer= rflag;\n");
Bprint(ftable, "#ifndef YYMAXDEPTH\n");
Bprint(ftable, "#define YYMAXDEPTH 150\n");
Bprint(ftable, "#endif\n" );
if(!ntypes) {
Bprint(ftable, "#ifndef YYSTYPE\n");
Bprint(ftable, "#define YYSTYPE int\n");
Bprint(ftable, "#endif\n");
=
}
if(!yyarg){
Bprint(ftable, "YYSTYPE yylval;\n");
Bprint(ftable, "YYSTY= PE yyval;\n");
}else{=
if(dflag)
Bprint(ftable, "#include \"%s.%s\"\n\n", stem= c, FILED);
Bprint(fout, "struct Yyarg {\n");
Bprint(fout= , "\tint\tyynerrs;\n");
Bprint(fout, "\tint\tyyerrflag;\n");
=
Bprint(fout, "\tvoid*\targ;\n");
Bprint(fout, "\tYYSTYPE\tyyv= al;\n");
Bprint(fout, "\tYYSTYPE\tyylval;\n");
Bprint(fo= ut, "};\n\n");
}
prdptr[0] =3D mem;

=
/* added production */
*mem++ =3D NTBASE;

/* if start is 0, we will overwrite with the lhs of the first rule */<= /div>
*mem++ =3D start;
*mem++ =3D 1;
*mem++ =3D 0;<= /div>
prdptr[1] =3D mem;
while((t=3Dgettok()) =3D=3D LCURLY)
cpycode();
if(t !=3D IDENTCOLON)
error("bad syn= tax on first rule");

if(!start)
prdptr[0]= [1] =3D chfind(1, tokname);

/* read rules */
<= div>while(t !=3D MARK && t !=3D ENDFILE) {
/* process a ru= le */
rlines[nprod] =3D lineno;
if(t =3D=3D '|')
*mem++ =3D *prdptr[nprod-1];
else
if(t =3D=3D IDENTCO= LON) {
*mem =3D chfind(1, tokname);
if(*mem < NTBASE)=
error("token illegal on LHS of grammar rule");
mem++;
} else
error("illegal rule: missing semicolon or | ?");
/* read rule body */
t =3D gettok();

=
more_rule:
while(t =3D=3D IDENTIFIER) {
*mem =3D ch= find(1, tokname);
if(*mem < NTBASE)
levprd[nprod] =3D= toklev[*mem];
mem++;
t =3D gettok();
}
<= div>if(t =3D=3D PREC) {
if(gettok() !=3D IDENTIFIER)
err= or("illegal %%prec syntax");
j =3D chfind(2, tokname);
i= f(j >=3D NTBASE)
error("nonterminal %s illegal after %%prec",
nontrst[j-NTBASE].name);
levprd[nprod] =3D toklev[j];
t =3D gettok();
}
if(t =3D=3D '=3D') {
= levprd[nprod] |=3D ACTFLAG;
Bprint(faction, "\ncase %d:", nprod);<= /div>
cpyact(mem-prdptr[nprod]-1);
Bprint(faction, " break;");=
if((t=3Dgettok()) =3D=3D IDENTIFIER) {

/= * action within rule... */
sprint(actnm, "$$%d", nprod);

/* make it a nonterminal */
j =3D chfind(1, actnm)= ;

/*
* the current rule will become rule n= umber nprod+1
* move the contents down, and make room for the null=
*/
for(p =3D mem; p >=3D prdptr[nprod]; --p)
p[2] =3D *p;
mem +=3D 2;

/* enter null= production for action */
p =3D prdptr[nprod];
*p++ =3D j= ;
*p++ =3D -nprod;

/* update the producti= on information */
levprd[nprod+1] =3D levprd[nprod] & ~ACTFLAG= ;
levprd[nprod] =3D ACTFLAG;
if(++nprod >=3D NPROD)
error("more than %d rules", NPROD);
prdptr[nprod] =3D p;<= /div>

/* make the action appear in the original rule */
*mem++ =3D j;

/* get some more of the rule= */
goto more_rule;
}
}

while(t =3D=3D ';')
t =3D gettok();
*mem++ =3D -nprod= ;

/* check that default action is reasonable */
if(ntypes && !(levprd[nprod]&ACTFLAG) && nontrst[= *prdptr[nprod]-NTBASE].value) {

/* no explicit acti= on, LHS has value */
int tempty;

tempty =3D= prdptr[nprod][1];
if(tempty < 0)
error("must return a= value, since LHS has a type");
else
if(tempty >=3D N= TBASE)
tempty =3D nontrst[tempty-NTBASE].value;
else
tempty =3D TYPE(toklev[tempty]);
if(tempty !=3D nontrst[*pr= dptr[nprod]-NTBASE].value)
error("default action causes potential t= ype clash");
}
nprod++;
if(nprod >=3D NPROD= )
error("more than %d rules", NPROD);
prdptr[nprod] =3D m= em;
levprd[nprod] =3D 0;
}

/* e= nd of all rules */
defout(1);

finact();
if(t =3D=3D MARK) {
Bprint(ftable, "\n");
if(yy= line)
Bprint(ftable, "#line\t%d\t\"%s\"\n", lineno, infile);
=
while((c=3DBgetrune(finput)) !=3D Beof)
Bputrune(ftable, c);<= /div>
}
Bterm(finput);
}

<= /div>

On Wed, Nov 2= 5, 2015 at 10:03 AM, <plannine@sigint.cs.purdue.edu> wrote:
On Wed, Nov 25, 2015 at 09:25:55= AM -0500, Brantley Coile wrote:
> unindented consequences

Is that a class of Python bugs or an awesome name for a Nerdcore band?




--
Ryan
<= div dir=3D"ltr">[ERROR]: Your autotools build scripts are 200 lines longer t= han your program. Something=E2=80=99s wrong.
= --Apple-Mail-D7434540-E740-40AC-8464-6B207B7D36DC--