package/lua/patches/600-refcounting.patch

   1 --- a/src/lapi.c
   2 +++ b/src/lapi.c
   3 @@ -27,8 +27,8 @@
   4  #include "ltable.h"
   5  #include "ltm.h"
   6  #include "lundump.h"
   7 -#include "lvm.h"
   8  #include "lnum.h"
   9 +#include "lvm.h"
  10
  11
  12  const char lua_ident[] =
  13 @@ -117,6 +117,7 @@ LUA_API void lua_xmove (lua_State *from,
  14    from->top -= n;
  15    for (i = 0; i < n; i++) {
  16      setobj2s(to, to->top++, from->top + i);
  17 +    setnilvalue(from, from->top + i);
  18    }
  19    lua_unlock(to);
  20  }
  21 @@ -166,12 +167,14 @@ LUA_API void lua_settop (lua_State *L, i
  22    if (idx >= 0) {
  23      api_check(L, idx <= L->stack_last - L->base);
  24      while (L->top < L->base + idx)
  25 -      setnilvalue(L->top++);
  26 +      setnilvalue(L, L->top++);
  27      L->top = L->base + idx;
  28 +    setnilvalue(L, L->top);
  29    }
  30    else {
  31 +    int i;
  32      api_check(L, -(idx+1) <= (L->top - L->base));
  33 -    L->top += idx+1;  /* `subtract' index (index is negative) */
  34 +       setlvmtop(L, L->top + idx + 1); /* `subtract' index (index is negative) */
  35    }
  36    lua_unlock(L);
  37  }
  38 @@ -183,7 +186,7 @@ LUA_API void lua_remove (lua_State *L, i
  39    p = index2adr(L, idx);
  40    api_checkvalidindex(L, p);
  41    while (++p < L->top) setobjs2s(L, p-1, p);
  42 -  L->top--;
  43 +  setlvmtop(L, L->top - 1);
  44    lua_unlock(L);
  45  }
  46
  47 @@ -196,6 +199,7 @@ LUA_API void lua_insert (lua_State *L, i
  48    api_checkvalidindex(L, p);
  49    for (q = L->top; q>p; q--) setobjs2s(L, q, q-1);
  50    setobjs2s(L, p, L->top);
  51 +  setnilvalue(L, L->top);
  52    lua_unlock(L);
  53  }
  54
  55 @@ -220,7 +224,7 @@ LUA_API void lua_replace (lua_State *L,
  56      if (idx < LUA_GLOBALSINDEX)  /* function upvalue? */
  57        luaC_barrier(L, curr_func(L), L->top - 1);
  58    }
  59 -  L->top--;
  60 +  setlvmtop(L, L->top - 1);
  61    lua_unlock(L);
  62  }
  63
  64 @@ -259,14 +263,14 @@ LUA_API int lua_iscfunction (lua_State *
  65
  66
  67  LUA_API int lua_isnumber (lua_State *L, int idx) {
  68 -  TValue n;
  69 +  TValue n = tvinit();
  70    const TValue *o = index2adr(L, idx);
  71    return tonumber(o, &n);
  72  }
  73
  74
  75  LUA_API int lua_isinteger (lua_State *L, int idx) {
  76 -  TValue tmp;
  77 +  TValue tmp = tvinit();
  78    lua_Integer dum;
  79    const TValue *o = index2adr(L, idx);
  80    return tonumber(o,&tmp) && (ttisint(o) || tt_integer_valued(o,&dum));
  81 @@ -319,7 +323,7 @@ LUA_API int lua_lessthan (lua_State *L,
  82
  83
  84  LUA_API lua_Number lua_tonumber (lua_State *L, int idx) {
  85 -  TValue n;
  86 +  TValue n = tvinit();
  87    const TValue *o = index2adr(L, idx);
  88    if (tonumber(o, &n)) {
  89  #ifdef LNUM_COMPLEX
  90 @@ -333,7 +337,7 @@ LUA_API lua_Number lua_tonumber (lua_Sta
  91
  92
  93  LUA_API lua_Integer lua_tointeger (lua_State *L, int idx) {
  94 -  TValue n;
  95 +  TValue n = tvinit();
  96      /* Lua 5.1 documented behaviour is to return nonzero for non-integer:
  97       * "If the number is not an integer, it is truncated in some non-specified way."
  98       * I would suggest to change this, to return 0 for anything that would
  99 @@ -369,7 +373,7 @@ LUA_API lua_Integer lua_tointeger (lua_S
 100
 101  #ifdef LNUM_COMPLEX
 102  LUA_API lua_Complex lua_tocomplex (lua_State *L, int idx) {
 103 -  TValue tmp;
 104 +  TValue tmp = tvinit();
 105    const TValue *o = index2adr(L, idx);
 106    if (tonumber(o, &tmp))
 107      return nvalue_complex(o);
 108 @@ -465,7 +469,7 @@ LUA_API const void *lua_topointer (lua_S
 109
 110  LUA_API void lua_pushnil (lua_State *L) {
 111    lua_lock(L);
 112 -  setnilvalue(L->top);
 113 +  setnilvalue(L, L->top);
 114    api_incr_top(L);
 115    lua_unlock(L);
 116  }
 117 @@ -548,8 +552,10 @@ LUA_API void lua_pushcclosure (lua_State
 118    cl = luaF_newCclosure(L, n, getcurrenv(L));
 119    cl->c.f = fn;
 120    L->top -= n;
 121 -  while (n--)
 122 +  while (n--) {
 123      setobj2n(L, &cl->c.upvalue[n], L->top+n);
 124 +    setnilvalue(L, L->top + n);
 125 +  }
 126    setclvalue(L, L->top, cl);
 127    lua_assert(iswhite(obj2gco(cl)));
 128    api_incr_top(L);
 129 @@ -600,7 +606,7 @@ LUA_API void lua_gettable (lua_State *L,
 130
 131  LUA_API void lua_getfield (lua_State *L, int idx, const char *k) {
 132    StkId t;
 133 -  TValue key;
 134 +  TValue key = tvinit();
 135    lua_lock(L);
 136    t = index2adr(L, idx);
 137    api_checkvalidindex(L, t);
 138 @@ -689,7 +695,7 @@ LUA_API void lua_getfenv (lua_State *L,
 139        setobj2s(L, L->top,  gt(thvalue(o)));
 140        break;
 141      default:
 142 -      setnilvalue(L->top);
 143 +      setnilvalue(L, L->top);
 144        break;
 145    }
 146    api_incr_top(L);
 147 @@ -709,21 +715,21 @@ LUA_API void lua_settable (lua_State *L,
 148    t = index2adr(L, idx);
 149    api_checkvalidindex(L, t);
 150    luaV_settable(L, t, L->top - 2, L->top - 1);
 151 -  L->top -= 2;  /* pop index and value */
 152 +  setlvmtop(L, L->top - 2);  /* pop index and value */
 153    lua_unlock(L);
 154  }
 155
 156
 157  LUA_API void lua_setfield (lua_State *L, int idx, const char *k) {
 158    StkId t;
 159 -  TValue key;
 160 +  TValue key = tvinit();
 161    lua_lock(L);
 162    api_checknelems(L, 1);
 163    t = index2adr(L, idx);
 164    api_checkvalidindex(L, t);
 165    setsvalue(L, &key, luaS_new(L, k));
 166    luaV_settable(L, t, &key, L->top - 1);
 167 -  L->top--;  /* pop value */
 168 +  setlvmtop(L, L->top - 1);  /* pop value */
 169    lua_unlock(L);
 170  }
 171
 172 @@ -736,7 +742,7 @@ LUA_API void lua_rawset (lua_State *L, i
 173    api_check(L, ttistable(t));
 174    setobj2t(L, luaH_set(L, hvalue(t), L->top-2), L->top-1);
 175    luaC_barriert(L, hvalue(t), L->top-1);
 176 -  L->top -= 2;
 177 +  setlvmtop(L, L->top - 2);
 178    lua_unlock(L);
 179  }
 180
 181 @@ -749,7 +755,7 @@ LUA_API void lua_rawseti (lua_State *L,
 182    api_check(L, ttistable(o));
 183    setobj2t(L, luaH_setint(L, hvalue(o), n), L->top-1);
 184    luaC_barriert(L, hvalue(o), L->top-1);
 185 -  L->top--;
 186 +  setlvmtop(L, L->top - 1);
 187    lua_unlock(L);
 188  }
 189
 190 @@ -785,7 +791,7 @@ LUA_API int lua_setmetatable (lua_State
 191        break;
 192      }
 193    }
 194 -  L->top--;
 195 +  setlvmtop(L, L->top - 1);
 196    lua_unlock(L);
 197    return 1;
 198  }
 199 @@ -814,7 +820,7 @@ LUA_API int lua_setfenv (lua_State *L, i
 200        break;
 201    }
 202    if (res) luaC_objbarrier(L, gcvalue(o), hvalue(L->top - 1));
 203 -  L->top--;
 204 +  setlvmtop(L, L->top - 1);
 205    lua_unlock(L);
 206    return res;
 207  }
 208 @@ -1040,8 +1046,9 @@ LUA_API int lua_next (lua_State *L, int
 209    if (more) {
 210      api_incr_top(L);
 211    }
 212 -  else  /* no more elements */
 213 -    L->top -= 1;  /* remove key */
 214 +  else {  /* no more elements */
 215 +    setlvmtop(L, L->top - 1);  /* remove key */
 216 +  }
 217    lua_unlock(L);
 218    return more;
 219  }
 220 @@ -1053,7 +1060,7 @@ LUA_API void lua_concat (lua_State *L, i
 221    if (n >= 2) {
 222      luaC_checkGC(L);
 223      luaV_concat(L, n, cast_int(L->top - L->base) - 1);
 224 -    L->top -= (n-1);
 225 +    setlvmtop(L, L->top - (n-1));
 226    }
 227    else if (n == 0) {  /* push empty string */
 228      setsvalue2s(L, L->top, luaS_newlstr(L, "", 0));
 229 @@ -1139,6 +1146,7 @@ LUA_API const char *lua_setupvalue (lua_
 230    if (name) {
 231      L->top--;
 232      setobj(L, val, L->top);
 233 +    setnilvalue(L, L->top);
 234      luaC_barrier(L, clvalue(fi), L->top);
 235    }
 236    lua_unlock(L);
 237 @@ -1160,7 +1168,7 @@ LUA_API const char *lua_setupvalue (lua_
 238  int lua_pushvalue_as_number (lua_State *L, int idx)
 239  {
 240    const TValue *o = index2adr(L, idx);
 241 -  TValue tmp;
 242 +  TValue tmp = tvinit();
 243    lua_Integer i;
 244    if (ttisnumber(o)) {
 245      if ( (!ttisint(o)) && tt_integer_valued(o,&i)) {
 246 --- a/src/lcode.c
 247 +++ b/src/lcode.c
 248 @@ -23,6 +23,7 @@
 249  #include "lparser.h"
 250  #include "ltable.h"
 251  #include "lnum.h"
 252 +#include "lvm.h"
 253
 254
 255  #define hasjumps(e)    ((e)->t != (e)->f)
 256 @@ -248,7 +249,7 @@ static int addk (FuncState *fs, TValue *
 257      setivalue(idx, fs->nk);
 258      luaM_growvector(L, f->k, fs->nk, f->sizek, TValue,
 259                      MAXARG_Bx, "constant table overflow");
 260 -    while (oldsize < f->sizek) setnilvalue(&f->k[oldsize++]);
 261 +    while (oldsize < f->sizek) setnilvalue(L, &f->k[oldsize++]);
 262      setobj(L, &f->k[fs->nk], v);
 263      luaC_barrier(L, f, v);
 264      return fs->nk++;
 265 @@ -257,21 +258,24 @@ static int addk (FuncState *fs, TValue *
 266
 267
 268  int luaK_stringK (FuncState *fs, TString *s) {
 269 -  TValue o;
 270 +  TValue o = tvinit();
 271    setsvalue(fs->L, &o, s);
 272 +  luaV_unref(fs->L, &o);
 273    return addk(fs, &o, &o);
 274  }
 275
 276
 277  int luaK_numberK (FuncState *fs, lua_Number r) {
 278 -  TValue o;
 279 +  lua_State *L = fs->L;
 280 +  TValue o = tvinit();
 281    setnvalue(&o, r);
 282    return addk(fs, &o, &o);
 283  }
 284
 285
 286  int luaK_integerK (FuncState *fs, lua_Integer r) {
 287 -  TValue o;
 288 +  lua_State *L = fs->L;
 289 +  TValue o = tvinit();
 290    setivalue(&o, r);
 291    return addk(fs, &o, &o);
 292  }
 293 @@ -279,22 +283,24 @@ int luaK_integerK (FuncState *fs, lua_In
 294
 295  #ifdef LNUM_COMPLEX
 296  static int luaK_imagK (FuncState *fs, lua_Number r) {
 297 -  TValue o;
 298 +  lua_State *L = fs->L;
 299 +  TValue o = tvinit();
 300    setnvalue_complex(&o, r*I);
 301    return addk(fs, &o, &o);
 302  }
 303  #endif
 304
 305  static int boolK (FuncState *fs, int b) {
 306 -  TValue o;
 307 +  lua_State *L = fs->L;
 308 +  TValue o = tvinit();
 309    setbvalue(&o, b);
 310    return addk(fs, &o, &o);
 311  }
 312
 313
 314  static int nilK (FuncState *fs) {
 315 -  TValue k, v;
 316 -  setnilvalue(&v);
 317 +  TValue k = tvinit(), v = tvinit();
 318 +  setnilvalue(fs->L, &v);
 319    /* cannot use nil as key; instead use table itself to represent nil */
 320    sethvalue(fs->L, &k, fs->h);
 321    return addk(fs, &k, &v);
 322 --- a/src/ldebug.c
 323 +++ b/src/ldebug.c
 324 @@ -142,6 +142,7 @@ LUA_API const char *lua_setlocal (lua_St
 325    if (name)
 326        setobjs2s(L, ci->base + (n - 1), L->top - 1);
 327    L->top--;  /* pop value */
 328 +  setnilvalue(L, L->top);
 329    lua_unlock(L);
 330    return name;
 331  }
 332 @@ -176,7 +177,7 @@ static void info_tailcall (lua_Debug *ar
 333
 334  static void collectvalidlines (lua_State *L, Closure *f) {
 335    if (f == NULL || f->c.isC) {
 336 -    setnilvalue(L->top);
 337 +    setnilvalue(L, L->top);
 338    }
 339    else {
 340      Table *t = luaH_new(L, 0, 0);
 341 @@ -248,7 +249,7 @@ LUA_API int lua_getinfo (lua_State *L, c
 342    }
 343    status = auxgetinfo(L, what, ar, f, ci);
 344    if (strchr(what, 'f')) {
 345 -    if (f == NULL) setnilvalue(L->top);
 346 +    if (f == NULL) setnilvalue(L, L->top);
 347      else setclvalue(L, L->top, f);
 348      incr_top(L);
 349    }
 350 @@ -586,7 +587,7 @@ void luaG_concaterror (lua_State *L, Stk
 351
 352
 353  void luaG_aritherror (lua_State *L, const TValue *p1, const TValue *p2) {
 354 -  TValue temp;
 355 +  TValue temp = tvinit();
 356    if (luaV_tonumber(p1, &temp) == NULL)
 357      p2 = p1;  /* first operand is wrong */
 358    luaG_typeerror(L, p2, "perform arithmetic on");
 359 --- a/src/ldo.c
 360 +++ b/src/ldo.c
 361 @@ -211,7 +211,7 @@ static StkId adjust_varargs (lua_State *
 362    Table *htab = NULL;
 363    StkId base, fixed;
 364    for (; actual < nfixargs; ++actual)
 365 -    setnilvalue(L->top++);
 366 +    setnilvalue(L, L->top++);
 367  #if defined(LUA_COMPAT_VARARG)
 368    if (p->is_vararg & VARARG_NEEDSARG) { /* compat. with old-style vararg? */
 369      int nvar = actual - nfixargs;  /* number of extra arguments */
 370 @@ -229,7 +229,7 @@ static StkId adjust_varargs (lua_State *
 371    base = L->top;  /* final position of first argument */
 372    for (i=0; i<nfixargs; i++) {
 373      setobjs2s(L, L->top++, fixed+i);
 374 -    setnilvalue(fixed+i);
 375 +    setnilvalue(L, fixed+i);
 376    }
 377    /* add `arg' parameter */
 378    if (htab) {
 379 @@ -294,7 +294,7 @@ int luaD_precall (lua_State *L, StkId fu
 380      ci->tailcalls = 0;
 381      ci->nresults = nresults;
 382      for (st = L->top; st < ci->top; st++)
 383 -      setnilvalue(st);
 384 +      setnilvalue(L, st);
 385      L->top = ci->top;
 386      if (L->hookmask & LUA_MASKCALL) {
 387        L->savedpc++;  /* hooks assume 'pc' is already incremented */
 388 @@ -354,8 +354,8 @@ int luaD_poscall (lua_State *L, StkId fi
 389    for (i = wanted; i != 0 && firstResult < L->top; i--)
 390      setobjs2s(L, res++, firstResult++);
 391    while (i-- > 0)
 392 -    setnilvalue(res++);
 393 -  L->top = res;
 394 +    setnilvalue(L, res++);
 395 +  setlvmtop(L, res);
 396    return (wanted - LUA_MULTRET);  /* 0 iff wanted == LUA_MULTRET */
 397  }
 398
 399 @@ -463,8 +463,12 @@ int luaD_pcall (lua_State *L, Pfunc func
 400    status = luaD_rawrunprotected(L, func, u);
 401    if (status != 0) {  /* an error occurred? */
 402      StkId oldtop = restorestack(L, old_top);
 403 +       StkId curtop = L->top;
 404 +    int i;
 405      luaF_close(L, oldtop);  /* close eventual pending closures */
 406      luaD_seterrorobj(L, status, oldtop);
 407 +    for (i = (curtop - L->top); i-- > 0;)
 408 +      setnilvalue(L, L->top + i);
 409      L->nCcalls = oldnCcalls;
 410      L->ci = restoreci(L, old_ci);
 411      L->base = L->ci->base;
 412 --- a/src/lfunc.c
 413 +++ b/src/lfunc.c
 414 @@ -17,7 +17,7 @@
 415  #include "lmem.h"
 416  #include "lobject.h"
 417  #include "lstate.h"
 418 -
 419 +#include "lvm.h"
 420
 421
 422  Closure *luaF_newCclosure (lua_State *L, int nelems, Table *e) {
 423 @@ -45,7 +45,7 @@ UpVal *luaF_newupval (lua_State *L) {
 424    UpVal *uv = luaM_new(L, UpVal);
 425    luaC_link(L, obj2gco(uv), LUA_TUPVAL);
 426    uv->v = &uv->u.value;
 427 -  setnilvalue(uv->v);
 428 +  setnilvalue(L, uv->v);
 429    return uv;
 430  }
 431
 432 @@ -67,8 +67,14 @@ UpVal *luaF_findupval (lua_State *L, Stk
 433    uv = luaM_new(L, UpVal);  /* not found: create a new one */
 434    uv->tt = LUA_TUPVAL;
 435    uv->marked = luaC_white(g);
 436 -  uv->v = level;  /* current value lives in the stack */
 437 +  uv->v = luaV_ref(level);  /* current value lives in the stack */
 438    uv->next = *pp;  /* chain it in the proper position */
 439 +  if (uv->next) {
 440 +       uv->prev = uv->next->gch.prev;
 441 +    uv->next->gch.prev = (GCObject *)uv;
 442 +  } else {
 443 +    uv->prev = NULL;
 444 +  }
 445    *pp = obj2gco(uv);
 446    uv->u.l.prev = &g->uvhead;  /* double link it in `uvhead' list */
 447    uv->u.l.next = g->uvhead.u.l.next;
 448 --- a/src/lgc.c
 449 +++ b/src/lgc.c
 450 @@ -21,6 +21,7 @@
 451  #include "lstring.h"
 452  #include "ltable.h"
 453  #include "ltm.h"
 454 +#include "lvm.h"
 455
 456
 457  #define GCSTEPSIZE     1024u
 458 @@ -265,7 +266,7 @@ static void traversestack (global_State
 459    for (o = l->stack; o < l->top; o++)
 460      markvalue(g, o);
 461    for (; o <= lim; o++)
 462 -    setnilvalue(o);
 463 +    setnilvalue(l, o);
 464    checkstacksizes(l, lim);
 465  }
 466
 467 @@ -348,7 +349,7 @@ static int iscleared (const TValue *o, i
 468  /*
 469  ** clear collected entries from weaktables
 470  */
 471 -static void cleartable (GCObject *l) {
 472 +static void cleartable (lua_State *L, GCObject *l) {
 473    while (l) {
 474      Table *h = gco2h(l);
 475      int i = h->sizearray;
 476 @@ -358,7 +359,7 @@ static void cleartable (GCObject *l) {
 477        while (i--) {
 478          TValue *o = &h->array[i];
 479          if (iscleared(o, 0))  /* value was collected? */
 480 -          setnilvalue(o);  /* remove value */
 481 +          setnilvalue(L, o);  /* remove value */
 482        }
 483      }
 484      i = sizenode(h);
 485 @@ -366,7 +367,7 @@ static void cleartable (GCObject *l) {
 486        Node *n = gnode(h, i);
 487        if (!ttisnil(gval(n)) &&  /* non-empty entry? */
 488            (iscleared(key2tval(n), 1) || iscleared(gval(n), 0))) {
 489 -        setnilvalue(gval(n));  /* remove value ... */
 490 +        setnilvalue(L, gval(n));  /* remove value ... */
 491          removeentry(n);  /* remove entry from table */
 492        }
 493      }
 494 @@ -375,7 +376,7 @@ static void cleartable (GCObject *l) {
 495  }
 496
 497
 498 -static void freeobj (lua_State *L, GCObject *o) {
 499 +void luaC_freeobj (lua_State *L, GCObject *o) {
 500    switch (o->gch.tt) {
 501      case LUA_TPROTO: luaF_freeproto(L, gco2p(o)); break;
 502      case LUA_TFUNCTION: luaF_freeclosure(L, gco2cl(o)); break;
 503 @@ -418,10 +419,12 @@ static GCObject **sweeplist (lua_State *
 504      }
 505      else {  /* must erase `curr' */
 506        lua_assert(isdead(g, curr) || deadmask == bitmask(SFIXEDBIT));
 507 +      if (curr->gch.next)
 508 +        curr->gch.next->gch.prev = curr->gch.prev;
 509        *p = curr->gch.next;
 510        if (curr == g->rootgc)  /* is the first element of the list? */
 511          g->rootgc = curr->gch.next;  /* adjust first */
 512 -      freeobj(L, curr);
 513 +      luaC_freeobj(L, curr);
 514      }
 515    }
 516    return p;
 517 @@ -543,7 +546,7 @@ static void atomic (lua_State *L) {
 518    udsize = luaC_separateudata(L, 0);  /* separate userdata to be finalized */
 519    marktmu(g);  /* mark `preserved' userdata */
 520    udsize += propagateall(g);  /* remark, to propagate `preserveness' */
 521 -  cleartable(g->weak);  /* remove collected objects from weak tables */
 522 +  cleartable(L, g->weak);  /* remove collected objects from weak tables */
 523    /* flip current white */
 524    g->currentwhite = cast_byte(otherwhite(g));
 525    g->sweepstrgc = 0;
 526 @@ -685,8 +688,11 @@ void luaC_barrierback (lua_State *L, Tab
 527
 528  void luaC_link (lua_State *L, GCObject *o, lu_byte tt) {
 529    global_State *g = G(L);
 530 +  o->gch.prev = (GCObject*)&g->rootgc;
 531    o->gch.next = g->rootgc;
 532    g->rootgc = o;
 533 +  if (o->gch.next)
 534 +    o->gch.next->gch.prev = o;
 535    o->gch.marked = luaC_white(g);
 536    o->gch.tt = tt;
 537  }
 538 --- a/src/lgc.h
 539 +++ b/src/lgc.h
 540 @@ -105,6 +105,6 @@ LUAI_FUNC void luaC_link (lua_State *L,
 541  LUAI_FUNC void luaC_linkupval (lua_State *L, UpVal *uv);
 542  LUAI_FUNC void luaC_barrierf (lua_State *L, GCObject *o, GCObject *v);
 543  LUAI_FUNC void luaC_barrierback (lua_State *L, Table *t);
 544 -
 545 +LUAI_FUNC void luaC_freeobj (lua_State *L, GCObject *o);
 546
 547  #endif
 548 --- a/src/lmem.c
 549 +++ b/src/lmem.c
 550 @@ -6,6 +6,7 @@
 551
 552
 553  #include <stddef.h>
 554 +#include <string.h>
 555
 556  #define lmem_c
 557  #define LUA_CORE
 558 @@ -80,6 +81,8 @@ void *luaM_realloc_ (lua_State *L, void
 559    if (block == NULL && nsize > 0)
 560      luaD_throw(L, LUA_ERRMEM);
 561    lua_assert((nsize == 0) == (block == NULL));
 562 +  if (nsize > osize)
 563 +    memset((char *)block + osize, 0, nsize - osize);
 564    g->totalbytes = (g->totalbytes - osize) + nsize;
 565    return block;
 566  }
 567 --- a/src/lobject.h
 568 +++ b/src/lobject.h
 569 @@ -44,7 +44,7 @@ typedef union GCObject GCObject;
 570  ** Common Header for all collectable objects (in macro form, to be
 571  ** included in other objects)
 572  */
 573 -#define CommonHeader   GCObject *next; lu_byte tt; lu_byte marked
 574 +#define CommonHeader   GCObject *next; GCObject *prev; lu_byte tt; lu_byte marked
 575
 576
 577  /*
 578 @@ -83,6 +83,7 @@ typedef struct lua_TValue {
 579    TValuefields;
 580  } TValue;
 581
 582 +#define tvinit() { .value.b = 0, .tt = 0 }
 583
 584  /* Macros to test type */
 585  #define ttisnil(o)     (ttype(o) == LUA_TNIL)
 586 @@ -145,15 +146,15 @@ typedef struct lua_TValue {
 587
 588
 589  /* Macros to set values */
 590 -#define setnilvalue(obj) ((obj)->tt=LUA_TNIL)
 591 +#define setnilvalue(L, obj) (luaV_unref(L, (obj))->tt=LUA_TNIL)
 592
 593  /* Must not have side effects, 'x' may be expression.
 594  */
 595  #define setivalue(obj,x) \
 596 -    { TValue *i_o=(obj); i_o->value.i=(x); i_o->tt=LUA_TINT; }
 597 +    { TValue *i_o=luaV_unref(L, (obj)); i_o->value.i=(x); i_o->tt=LUA_TINT; }
 598
 599  # define setnvalue(obj,x) \
 600 -    { TValue *i_o=(obj); i_o->value.n= (x); i_o->tt=LUA_TNUMBER; }
 601 +    { TValue *i_o=luaV_unref(L, (obj)); i_o->value.n= (x); i_o->tt=LUA_TNUMBER; }
 602
 603  /* Note: Complex always has "inline", both are C99.
 604  */
 605 @@ -170,45 +171,45 @@ typedef struct lua_TValue {
 606
 607
 608  #define setpvalue(obj,x) \
 609 -  { TValue *i_o=(obj); i_o->value.p=(x); i_o->tt=LUA_TLIGHTUSERDATA; }
 610 +  { TValue *i_o=luaV_unref(L, (obj)); i_o->value.p=(x); i_o->tt=LUA_TLIGHTUSERDATA; }
 611
 612  #define setbvalue(obj,x) \
 613 -  { TValue *i_o=(obj); i_o->value.b=(x); i_o->tt=LUA_TBOOLEAN; }
 614 +  { TValue *i_o=luaV_unref(L, (obj)); i_o->value.b=(x); i_o->tt=LUA_TBOOLEAN; }
 615
 616  #define setsvalue(L,obj,x) \
 617 -  { TValue *i_o=(obj); \
 618 -    i_o->value.gc=cast(GCObject *, (x)); i_o->tt=LUA_TSTRING; \
 619 +  { TValue *i_o=(obj); TString *val=(x); luaS_ref(val); luaV_unref(L, obj); \
 620 +    i_o->value.gc=cast(GCObject *, (val)); i_o->tt=LUA_TSTRING; \
 621      checkliveness(G(L),i_o); }
 622
 623  #define setuvalue(L,obj,x) \
 624 -  { TValue *i_o=(obj); \
 625 +  { TValue *i_o=luaV_unref(L, (obj)); \
 626      i_o->value.gc=cast(GCObject *, (x)); i_o->tt=LUA_TUSERDATA; \
 627      checkliveness(G(L),i_o); }
 628
 629  #define setthvalue(L,obj,x) \
 630 -  { TValue *i_o=(obj); \
 631 +  { TValue *i_o=luaV_unref(L, (obj)); \
 632      i_o->value.gc=cast(GCObject *, (x)); i_o->tt=LUA_TTHREAD; \
 633      checkliveness(G(L),i_o); }
 634
 635  #define setclvalue(L,obj,x) \
 636 -  { TValue *i_o=(obj); \
 637 +  { TValue *i_o=luaV_unref(L, (obj)); \
 638      i_o->value.gc=cast(GCObject *, (x)); i_o->tt=LUA_TFUNCTION; \
 639      checkliveness(G(L),i_o); }
 640
 641  #define sethvalue(L,obj,x) \
 642 -  { TValue *i_o=(obj); \
 643 +  { TValue *i_o=luaV_unref(L, (obj)); \
 644      i_o->value.gc=cast(GCObject *, (x)); i_o->tt=LUA_TTABLE; \
 645      checkliveness(G(L),i_o); }
 646
 647  #define setptvalue(L,obj,x) \
 648 -  { TValue *i_o=(obj); \
 649 +  { TValue *i_o=luaV_unref(L, (obj)); \
 650      i_o->value.gc=cast(GCObject *, (x)); i_o->tt=LUA_TPROTO; \
 651      checkliveness(G(L),i_o); }
 652
 653  #define setobj(L,obj1,obj2) \
 654 -  { const TValue *o2=(obj2); TValue *o1=(obj1); \
 655 +  do { const TValue *o2=luaV_ref((TValue *)(obj2)); TValue *o1=luaV_unref(L, (obj1)); \
 656      o1->value = o2->value; o1->tt=o2->tt; \
 657 -    checkliveness(G(L),o1); }
 658 +    checkliveness(G(L),o1); } while(0)
 659
 660
 661  /*
 662 @@ -253,6 +254,7 @@ typedef union TString {
 663      lu_byte reserved;
 664      unsigned int hash;
 665      size_t len;
 666 +    int refcount;
 667    } tsv;
 668  } TString;
 669
 670 @@ -409,6 +411,7 @@ typedef struct Table {
 671  #define twoto(x)       (1<<(x))
 672  #define sizenode(t)    (twoto((t)->lsizenode))
 673
 674 +#include "lstring.h"
 675
 676  #define luaO_nilobject         (&luaO_nilobject_)
 677
 678 --- a/src/lparser.c
 679 +++ b/src/lparser.c
 680 @@ -24,6 +24,7 @@
 681  #include "lstate.h"
 682  #include "lstring.h"
 683  #include "ltable.h"
 684 +#include "lvm.h"
 685
 686
 687
 688 @@ -146,7 +147,7 @@ static int registerlocalvar (LexState *l
 689    luaM_growvector(ls->L, f->locvars, fs->nlocvars, f->sizelocvars,
 690                    LocVar, SHRT_MAX, "too many local variables");
 691    while (oldsize < f->sizelocvars) f->locvars[oldsize++].varname = NULL;
 692 -  f->locvars[fs->nlocvars].varname = varname;
 693 +  f->locvars[fs->nlocvars].varname = luaS_ref(varname);
 694    luaC_objbarrier(ls->L, f, varname);
 695    return fs->nlocvars++;
 696  }
 697 @@ -194,7 +195,7 @@ static int indexupvalue (FuncState *fs,
 698    luaM_growvector(fs->L, f->upvalues, f->nups, f->sizeupvalues,
 699                    TString *, MAX_INT, "");
 700    while (oldsize < f->sizeupvalues) f->upvalues[oldsize++] = NULL;
 701 -  f->upvalues[f->nups] = name;
 702 +  f->upvalues[f->nups] = luaS_ref(name);
 703    luaC_objbarrier(fs->L, f, name);
 704    lua_assert(v->k == VLOCAL || v->k == VUPVAL);
 705    fs->upvalues[f->nups].k = cast_byte(v->k);
 706 @@ -341,7 +342,7 @@ static void open_func (LexState *ls, Fun
 707    fs->nlocvars = 0;
 708    fs->nactvar = 0;
 709    fs->bl = NULL;
 710 -  f->source = ls->source;
 711 +  f->source = luaS_ref(ls->source);
 712    f->maxstacksize = 2;  /* registers 0/1 are always valid */
 713    fs->h = luaH_new(L, 0, 0);
 714    /* anchor table of constants and prototype (to avoid being collected) */
 715 --- a/src/lstate.c
 716 +++ b/src/lstate.c
 717 @@ -22,6 +22,7 @@
 718  #include "lstring.h"
 719  #include "ltable.h"
 720  #include "ltm.h"
 721 +#include "lvm.h"
 722
 723
 724  #define state_size(x)  (sizeof(x) + LUAI_EXTRASPACE)
 725 @@ -52,7 +53,7 @@ static void stack_init (lua_State *L1, l
 726    L1->stack_last = L1->stack+(L1->stacksize - EXTRA_STACK)-1;
 727    /* initialize first ci */
 728    L1->ci->func = L1->top;
 729 -  setnilvalue(L1->top++);  /* `function' entry for this `ci' */
 730 +  setnilvalue(L1, L1->top++);  /* `function' entry for this `ci' */
 731    L1->base = L1->ci->base = L1->top;
 732    L1->ci->top = L1->top + LUA_MINSTACK;
 733  }
 734 @@ -98,7 +99,7 @@ static void preinit_state (lua_State *L,
 735    L->base_ci = L->ci = NULL;
 736    L->savedpc = NULL;
 737    L->errfunc = 0;
 738 -  setnilvalue(gt(L));
 739 +  setnilvalue(L, gt(L));
 740  }
 741
 742
 743 @@ -163,7 +164,7 @@ LUA_API lua_State *lua_newstate (lua_All
 744    g->strt.size = 0;
 745    g->strt.nuse = 0;
 746    g->strt.hash = NULL;
 747 -  setnilvalue(registry(L));
 748 +  setnilvalue(L, registry(L));
 749    luaZ_initbuffer(L, &g->buff);
 750    g->panic = NULL;
 751    g->gcstate = GCSpause;
 752 --- a/src/lstring.c
 753 +++ b/src/lstring.c
 754 @@ -37,6 +37,9 @@ void luaS_resize (lua_State *L, int news
 755        int h1 = lmod(h, newsize);  /* new position */
 756        lua_assert(cast_int(h%newsize) == lmod(h, newsize));
 757        p->gch.next = newhash[h1];  /* chain it */
 758 +      if (p->gch.next)
 759 +        p->gch.next->gch.prev = p;
 760 +      p->gch.prev = NULL;
 761        newhash[h1] = p;
 762        p = next;
 763      }
 764 @@ -59,11 +62,15 @@ static TString *newlstr (lua_State *L, c
 765    ts->tsv.marked = luaC_white(G(L));
 766    ts->tsv.tt = LUA_TSTRING;
 767    ts->tsv.reserved = 0;
 768 +  ts->tsv.refcount = 0;
 769    memcpy(ts+1, str, l*sizeof(char));
 770    ((char *)(ts+1))[l] = '\0';  /* ending 0 */
 771    tb = &G(L)->strt;
 772    h = lmod(h, tb->size);
 773    ts->tsv.next = tb->hash[h];  /* chain new entry */
 774 +  if (ts->tsv.next)
 775 +    ts->tsv.next->gch.prev = (GCObject *)ts;
 776 +  ts->tsv.prev = NULL;
 777    tb->hash[h] = obj2gco(ts);
 778    tb->nuse++;
 779    if (tb->nuse > cast(lu_int32, tb->size) && tb->size <= MAX_INT/2)
 780 @@ -109,3 +116,29 @@ Udata *luaS_newudata (lua_State *L, size
 781    return u;
 782  }
 783
 784 +void luaS_unref(lua_State *L, TString *ts) {
 785 +  if (!L || !ts)
 786 +    return;
 787 +  if (testbit(ts->tsv.marked, FIXEDBIT))
 788 +    return;
 789 +  ts->tsv.refcount--;
 790 +  if (ts->tsv.refcount < 0) {
 791 +    fprintf(stderr, "REFCOUNT BUG, COUNT=%d, str=%s, len=%d\n", ts->tsv.refcount, (char *) (ts + 1), (int) ts->tsv.len);
 792 +  } else if (ts->tsv.refcount)
 793 +    return;
 794 +
 795 +  if (ts->tsv.prev) {
 796 +    ts->tsv.prev->gch.next = ts->tsv.next;
 797 +  } else {
 798 +    unsigned int idx = lmod(ts->tsv.hash, G(L)->strt.size);
 799 +    lua_assert(G(L)->strt.hash[index] == (GCObject*)ts);
 800 +    G(L)->strt.hash[idx] = ts->tsv.next;
 801 +  }
 802 +
 803 +  if (ts->tsv.next)
 804 +    ts->tsv.next->gch.prev = ts->tsv.prev;
 805 +
 806 +  luaC_freeobj(L, (GCObject *) ts);
 807 +}
 808 +
 809 +
 810 --- a/src/lstring.h
 811 +++ b/src/lstring.h
 812 @@ -7,7 +7,7 @@
 813  #ifndef lstring_h
 814  #define lstring_h
 815
 816 -
 817 +#include <stdio.h>
 818  #include "lgc.h"
 819  #include "lobject.h"
 820  #include "lstate.h"
 821 @@ -23,6 +23,12 @@
 822
 823  #define luaS_fix(s)    l_setbit((s)->tsv.marked, FIXEDBIT)
 824
 825 +static inline TString *luaS_ref(TString *ts) {
 826 +  ts->tsv.refcount++;
 827 +  return ts;
 828 +}
 829 +
 830 +LUA_API void luaS_unref(lua_State *L, TString *ts);
 831  LUAI_FUNC void luaS_resize (lua_State *L, int newsize);
 832  LUAI_FUNC Udata *luaS_newudata (lua_State *L, size_t s, Table *e);
 833  LUA_API TString *luaS_newlstr (lua_State *L, const char *str, size_t l);
 834 --- a/src/ltable.c
 835 +++ b/src/ltable.c
 836 @@ -34,6 +34,7 @@
 837  #include "lstate.h"
 838  #include "ltable.h"
 839  #include "lnum.h"
 840 +#include "lvm.h"
 841
 842
 843  /*
 844 @@ -278,7 +279,7 @@ static void setarrayvector (lua_State *L
 845    int i;
 846    luaM_reallocvector(L, t->array, t->sizearray, size, TValue);
 847    for (i=t->sizearray; i<size; i++)
 848 -     setnilvalue(&t->array[i]);
 849 +     setnilvalue(L, &t->array[i]);
 850    t->sizearray = size;
 851  }
 852
 853 @@ -299,8 +300,8 @@ static void setnodevector (lua_State *L,
 854      for (i=0; i<size; i++) {
 855        Node *n = gnode(t, i);
 856        gnext(n) = NULL;
 857 -      setnilvalue(gkey(n));
 858 -      setnilvalue(gval(n));
 859 +      setnilvalue(L, gkey(n));
 860 +      setnilvalue(L, gval(n));
 861      }
 862    }
 863    t->lsizenode = cast_byte(lsize);
 864 @@ -427,9 +428,11 @@ static TValue *newkey (lua_State *L, Tab
 865          othern = gnext(othern);  /* find previous */
 866        }
 867        gnext(othern) = n;  /* redo the chain with `n' in place of `mp' */
 868 +      luaV_ref((TValue *) gkey(mp));
 869 +      luaV_ref(gval(mp));
 870        *n = *mp;  /* copy colliding node into free pos. (mp->next also goes) */
 871        gnext(mp) = NULL;  /* now `mp' is free */
 872 -      setnilvalue(gval(mp));
 873 +      setnilvalue(L, gval(mp));
 874      }
 875      else {  /* colliding node is in its own main position */
 876        /* new node will go into free position */
 877 @@ -438,6 +441,7 @@ static TValue *newkey (lua_State *L, Tab
 878        mp = n;
 879      }
 880    }
 881 +  luaV_ref((TValue *) key);
 882    gkey(mp)->value = key->value; gkey(mp)->tt = key->tt;
 883    luaC_barriert(L, t, key);
 884    lua_assert(ttisnil(gval(mp)));
 885 @@ -530,7 +534,7 @@ TValue *luaH_setint (lua_State *L, Table
 886    if (p != luaO_nilobject)
 887      return cast(TValue *, p);
 888    else {
 889 -    TValue k;
 890 +    TValue k = tvinit();
 891      setivalue(&k, key);
 892      return newkey(L, t, &k);
 893    }
 894 @@ -542,7 +546,7 @@ TValue *luaH_setstr (lua_State *L, Table
 895    if (p != luaO_nilobject)
 896      return cast(TValue *, p);
 897    else {
 898 -    TValue k;
 899 +    TValue k = tvinit();
 900      setsvalue(L, &k, key);
 901      return newkey(L, t, &k);
 902    }
 903 --- a/src/luac.c
 904 +++ b/src/luac.c
 905 @@ -20,8 +20,9 @@
 906  #include "lmem.h"
 907  #include "lobject.h"
 908  #include "lopcodes.h"
 909 -#include "lstring.h"
 910  #include "lundump.h"
 911 +#include "lvm.h"
 912 +#include "lstring.h"
 913
 914  #define PROGNAME       "luac"          /* default program name */
 915  #define        OUTPUT          PROGNAME ".out" /* default output file */
 916 --- a/src/lundump.c
 917 +++ b/src/lundump.c
 918 @@ -19,6 +19,7 @@
 919  #include "lstring.h"
 920  #include "lundump.h"
 921  #include "lzio.h"
 922 +#include "lvm.h"
 923
 924  typedef struct {
 925   lua_State* L;
 926 @@ -133,7 +134,7 @@ static TString* LoadString(LoadState* S)
 927   {
 928    char* s=luaZ_openspace(S->L,S->b,size);
 929    LoadBlock(S,s,size);
 930 -  return luaS_newlstr(S->L,s,size-1);          /* remove trailing '\0' */
 931 +  return luaS_ref(luaS_newlstr(S->L,s,size-1));                /* remove trailing '\0' */
 932   }
 933  }
 934
 935 @@ -149,11 +150,12 @@ static Proto* LoadFunction(LoadState* S,
 936
 937  static void LoadConstants(LoadState* S, Proto* f)
 938  {
 939 + lua_State *L = S->L;
 940   int i,n;
 941   n=LoadInt(S);
 942   f->k=luaM_newvector(S->L,n,TValue);
 943   f->sizek=n;
 944 - for (i=0; i<n; i++) setnilvalue(&f->k[i]);
 945 + for (i=0; i<n; i++) setnilvalue(L, &f->k[i]);
 946   for (i=0; i<n; i++)
 947   {
 948    TValue* o=&f->k[i];
 949 @@ -161,7 +163,7 @@ static void LoadConstants(LoadState* S,
 950    switch (t)
 951    {
 952     case LUA_TNIL:
 953 -       setnilvalue(o);
 954 +       setnilvalue(L, o);
 955         break;
 956     case LUA_TBOOLEAN:
 957         setbvalue(o,LoadChar(S)!=0);
 958 @@ -229,6 +231,7 @@ static Proto* LoadFunction(LoadState* S,
 959   LoadDebug(S,f);
 960   IF (!luaG_checkcode(f), "bad code");
 961   S->L->top--;
 962 + setnilvalue(S->L, S->L->top);
 963   S->L->nCcalls--;
 964   return f;
 965  }
 966 --- a/src/lvm.c
 967 +++ b/src/lvm.c
 968 @@ -39,6 +39,7 @@
 969   * If 'obj' is a string, it is tried to be interpreted as a number.
 970   */
 971  const TValue *luaV_tonumber ( const TValue *obj, TValue *n) {
 972 +  lua_State *L = NULL; /* FIXME */
 973    lua_Number d;
 974    lua_Integer i;
 975
 976 @@ -384,6 +385,7 @@ void luaV_concat (lua_State *L, int tota
 977          size_t l = tsvalue(top-i)->len;
 978          memcpy(buffer+tl, svalue(top-i), l);
 979          tl += l;
 980 +               setnilvalue(L, top - i);
 981        }
 982        setsvalue2s(L, top-n, luaS_newlstr(L, buffer, tl));
 983      }
 984 @@ -420,7 +422,7 @@ void luaV_concat (lua_State *L, int tota
 985   */
 986  static void Arith (lua_State *L, StkId ra, const TValue *rb,
 987                     const TValue *rc, TMS op) {
 988 -  TValue tempb, tempc;
 989 +  TValue tempb = tvinit(), tempc = tvinit();
 990    const TValue *b, *c;
 991    lua_Number nb,nc;
 992
 993 @@ -663,7 +665,7 @@ void luaV_execute (lua_State *L, int nex
 994        OPCODE_TARGET(LOADNIL) {
 995          TValue *rb = RB(i);
 996          do {
 997 -          setnilvalue(rb--);
 998 +          setnilvalue(L, rb--);
 999          } while (rb >= ra);
1000          continue;
1001        }
1002 @@ -673,7 +675,7 @@ void luaV_execute (lua_State *L, int nex
1003          continue;
1004        }
1005        OPCODE_TARGET(GETGLOBAL) {
1006 -        TValue g;
1007 +        TValue g = tvinit();
1008          TValue *rb = KBx(i);
1009          sethvalue(L, &g, cl->env);
1010          lua_assert(ttisstring(rb));
1011 @@ -685,7 +687,7 @@ void luaV_execute (lua_State *L, int nex
1012          continue;
1013        }
1014        OPCODE_TARGET(SETGLOBAL) {
1015 -        TValue g;
1016 +        TValue g = tvinit();
1017          sethvalue(L, &g, cl->env);
1018          lua_assert(ttisstring(KBx(i)));
1019          Protect(luaV_settable(L, &g, KBx(i), ra));
1020 @@ -895,7 +897,7 @@ void luaV_execute (lua_State *L, int nex
1021          if (--nexeccalls == 0)  /* was previous function running `here'? */
1022            return;  /* no: return */
1023          else {  /* yes: continue its execution */
1024 -          if (b) L->top = L->ci->top;
1025 +          if (b) setlvmtop(L, L->ci->top);
1026            lua_assert(isLua(L->ci));
1027            lua_assert(GET_OPCODE(*((L->ci)->savedpc - 1)) == OP_CALL);
1028            goto reentry;
1029 @@ -986,6 +988,7 @@ void luaV_execute (lua_State *L, int nex
1030          for (; n > 0; n--) {
1031            TValue *val = ra+n;
1032            setobj2t(L, luaH_setint(L, h, last--), val);
1033 +          setnilvalue(L, val);
1034            luaC_barriert(L, h, val);
1035          }
1036          continue;
1037 @@ -1030,7 +1033,7 @@ void luaV_execute (lua_State *L, int nex
1038              setobjs2s(L, ra + j, ci->base - n + j);
1039            }
1040            else {
1041 -            setnilvalue(ra + j);
1042 +            setnilvalue(L, ra + j);
1043            }
1044          }
1045          continue;
1046 --- a/src/lvm.h
1047 +++ b/src/lvm.h
1048 @@ -11,6 +11,7 @@
1049  #include "ldo.h"
1050  #include "lobject.h"
1051  #include "ltm.h"
1052 +#include "lstring.h"
1053
1054
1055  #define tostring(L,o) ((ttype(o) == LUA_TSTRING) || (luaV_tostring(L, o)))
1056 @@ -19,6 +20,19 @@
1057
1058  #define equalobj(L,o1,o2) (ttype_ext_same(o1,o2) && luaV_equalval(L, o1, o2))
1059
1060 +static inline TValue *luaV_ref(TValue *tv)
1061 +{
1062 +  if (ttisstring(tv))
1063 +    luaS_ref(rawtsvalue(tv));
1064 +  return tv;
1065 +}
1066 +
1067 +static inline TValue *luaV_unref(lua_State *L, TValue *tv)
1068 +{
1069 +  if (ttisstring(tv))
1070 +    luaS_unref(L, rawtsvalue(tv));
1071 +  return tv;
1072 +}
1073
1074  LUAI_FUNC int luaV_lessthan (lua_State *L, const TValue *l, const TValue *r);
1075  LUAI_FUNC int luaV_equalval (lua_State *L, const TValue *t1, const TValue *t2);
1076 --- a/src/llex.c
1077 +++ b/src/llex.c
1078 @@ -23,6 +23,7 @@
1079  #include "ltable.h"
1080  #include "lzio.h"
1081  #include "lnum.h"
1082 +#include "lvm.h"
1083
1084
1085
1086 @@ -69,7 +70,7 @@ static void save (LexState *ls, int c) {
1087  void luaX_init (lua_State *L) {
1088    int i;
1089    for (i=0; i<NUM_RESERVED; i++) {
1090 -    TString *ts = luaS_new(L, luaX_tokens[i]);
1091 +    TString *ts = luaS_ref(luaS_new(L, luaX_tokens[i]));
1092      luaS_fix(ts);  /* reserved words are never collected */
1093      lua_assert(strlen(luaX_tokens[i])+1 <= TOKEN_LEN);
1094      ts->tsv.reserved = cast_byte(i+1);  /* reserved word */
1095 @@ -125,7 +126,7 @@ void luaX_syntaxerror (LexState *ls, con
1096
1097  TString *luaX_newstring (LexState *ls, const char *str, size_t l) {
1098    lua_State *L = ls->L;
1099 -  TString *ts = luaS_newlstr(L, str, l);
1100 +  TString *ts = luaS_ref(luaS_newlstr(L, str, l));
1101    TValue *o = luaH_setstr(L, ls->fs->h, ts);  /* entry for `str' */
1102    if (ttisnil(o))
1103      setbvalue(o, 1);  /* make sure `str' will not be collected */
1104 @@ -152,7 +153,7 @@ void luaX_setinput (lua_State *L, LexSta
1105    ls->fs = NULL;
1106    ls->linenumber = 1;
1107    ls->lastline = 1;
1108 -  ls->source = source;
1109 +  ls->source = luaS_ref(source);
1110    luaZ_resizebuffer(ls->L, ls->buff, LUA_MINBUFFER);  /* initialize buffer */
1111    next(ls);  /* read first char */
1112  }
1113 --- a/src/lstate.h
1114 +++ b/src/lstate.h
1115 @@ -144,6 +144,13 @@ union GCObject {
1116    struct lua_State th;  /* thread */
1117  };
1118
1119 +#define setlvmtop(L, val) do { \
1120 +       int __i; \
1121 +       for (__i = L->top - val; __i-- > 0;) \
1122 +               setnilvalue(L, val + __i); \
1123 +       L->top = val; \
1124 +} while (0)
1125 +
1126
1127  /* macros to convert a GCObject into a specific value */
1128  #define rawgco2ts(o)   check_exp((o)->gch.tt == LUA_TSTRING, &((o)->ts))