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 @@ -1040,20 +1046,21 @@ 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
 221
 222  LUA_API void lua_concat (lua_State *L, int n) {
 223    lua_lock(L);
 224    api_checknelems(L, n);
 225    if (n >= 2) {
 226      luaC_checkGC(L);
 227      luaV_concat(L, n, cast_int(L->top - L->base) - 1);
 228 -    L->top -= (n-1);
 229 +    setlvmtop(L, L->top - (n-1));
 230    }
 231    else if (n == 0) {  /* push empty string */
 232      setsvalue2s(L, L->top, luaS_newlstr(L, "", 0));
 233 @@ -1139,6 +1147,7 @@ LUA_API const char *lua_setupvalue (lua_
 234    if (name) {
 235      L->top--;
 236      setobj(L, val, L->top);
 237 +    setnilvalue(L, L->top);
 238      luaC_barrier(L, clvalue(fi), L->top);
 239    }
 240    lua_unlock(L);
 241 @@ -1160,7 +1169,7 @@ LUA_API const char *lua_setupvalue (lua_
 242  int lua_pushvalue_as_number (lua_State *L, int idx)
 243  {
 244    const TValue *o = index2adr(L, idx);
 245 -  TValue tmp;
 246 +  TValue tmp = tvinit();
 247    lua_Integer i;
 248    if (ttisnumber(o)) {
 249      if ( (!ttisint(o)) && tt_integer_valued(o,&i)) {
 250 --- a/src/lcode.c
 251 +++ b/src/lcode.c
 252 @@ -23,6 +23,7 @@
 253  #include "lparser.h"
 254  #include "ltable.h"
 255  #include "lnum.h"
 256 +#include "lvm.h"
 257
 258
 259  #define hasjumps(e)    ((e)->t != (e)->f)
 260 @@ -248,7 +249,7 @@ static int addk (FuncState *fs, TValue *
 261      setivalue(idx, fs->nk);
 262      luaM_growvector(L, f->k, fs->nk, f->sizek, TValue,
 263                      MAXARG_Bx, "constant table overflow");
 264 -    while (oldsize < f->sizek) setnilvalue(&f->k[oldsize++]);
 265 +    while (oldsize < f->sizek) setnilvalue(L, &f->k[oldsize++]);
 266      setobj(L, &f->k[fs->nk], v);
 267      luaC_barrier(L, f, v);
 268      return fs->nk++;
 269 @@ -257,21 +258,24 @@ static int addk (FuncState *fs, TValue *
 270
 271
 272  int luaK_stringK (FuncState *fs, TString *s) {
 273 -  TValue o;
 274 +  TValue o = tvinit();
 275    setsvalue(fs->L, &o, s);
 276 +  luaV_unref(fs->L, &o);
 277    return addk(fs, &o, &o);
 278  }
 279
 280
 281  int luaK_numberK (FuncState *fs, lua_Number r) {
 282 -  TValue o;
 283 +  lua_State *L = fs->L;
 284 +  TValue o = tvinit();
 285    setnvalue(&o, r);
 286    return addk(fs, &o, &o);
 287  }
 288
 289
 290  int luaK_integerK (FuncState *fs, lua_Integer r) {
 291 -  TValue o;
 292 +  lua_State *L = fs->L;
 293 +  TValue o = tvinit();
 294    setivalue(&o, r);
 295    return addk(fs, &o, &o);
 296  }
 297 @@ -279,22 +283,24 @@ int luaK_integerK (FuncState *fs, lua_In
 298
 299  #ifdef LNUM_COMPLEX
 300  static int luaK_imagK (FuncState *fs, lua_Number r) {
 301 -  TValue o;
 302 +  lua_State *L = fs->L;
 303 +  TValue o = tvinit();
 304    setnvalue_complex(&o, r*I);
 305    return addk(fs, &o, &o);
 306  }
 307  #endif
 308
 309  static int boolK (FuncState *fs, int b) {
 310 -  TValue o;
 311 +  lua_State *L = fs->L;
 312 +  TValue o = tvinit();
 313    setbvalue(&o, b);
 314    return addk(fs, &o, &o);
 315  }
 316
 317
 318  static int nilK (FuncState *fs) {
 319 -  TValue k, v;
 320 -  setnilvalue(&v);
 321 +  TValue k = tvinit(), v = tvinit();
 322 +  setnilvalue(fs->L, &v);
 323    /* cannot use nil as key; instead use table itself to represent nil */
 324    sethvalue(fs->L, &k, fs->h);
 325    return addk(fs, &k, &v);
 326 --- a/src/ldebug.c
 327 +++ b/src/ldebug.c
 328 @@ -142,6 +142,7 @@ LUA_API const char *lua_setlocal (lua_St
 329    if (name)
 330        setobjs2s(L, ci->base + (n - 1), L->top - 1);
 331    L->top--;  /* pop value */
 332 +  setnilvalue(L, L->top);
 333    lua_unlock(L);
 334    return name;
 335  }
 336 @@ -176,7 +177,7 @@ static void info_tailcall (lua_Debug *ar
 337
 338  static void collectvalidlines (lua_State *L, Closure *f) {
 339    if (f == NULL || f->c.isC) {
 340 -    setnilvalue(L->top);
 341 +    setnilvalue(L, L->top);
 342    }
 343    else {
 344      Table *t = luaH_new(L, 0, 0);
 345 @@ -248,7 +249,7 @@ LUA_API int lua_getinfo (lua_State *L, c
 346    }
 347    status = auxgetinfo(L, what, ar, f, ci);
 348    if (strchr(what, 'f')) {
 349 -    if (f == NULL) setnilvalue(L->top);
 350 +    if (f == NULL) setnilvalue(L, L->top);
 351      else setclvalue(L, L->top, f);
 352      incr_top(L);
 353    }
 354 @@ -586,7 +587,7 @@ void luaG_concaterror (lua_State *L, Stk
 355
 356
 357  void luaG_aritherror (lua_State *L, const TValue *p1, const TValue *p2) {
 358 -  TValue temp;
 359 +  TValue temp = tvinit();
 360    if (luaV_tonumber(p1, &temp) == NULL)
 361      p2 = p1;  /* first operand is wrong */
 362    luaG_typeerror(L, p2, "perform arithmetic on");
 363 --- a/src/ldo.c
 364 +++ b/src/ldo.c
 365 @@ -211,7 +211,7 @@ static StkId adjust_varargs (lua_State *
 366    Table *htab = NULL;
 367    StkId base, fixed;
 368    for (; actual < nfixargs; ++actual)
 369 -    setnilvalue(L->top++);
 370 +    setnilvalue(L, L->top++);
 371  #if defined(LUA_COMPAT_VARARG)
 372    if (p->is_vararg & VARARG_NEEDSARG) { /* compat. with old-style vararg? */
 373      int nvar = actual - nfixargs;  /* number of extra arguments */
 374 @@ -229,7 +229,7 @@ static StkId adjust_varargs (lua_State *
 375    base = L->top;  /* final position of first argument */
 376    for (i=0; i<nfixargs; i++) {
 377      setobjs2s(L, L->top++, fixed+i);
 378 -    setnilvalue(fixed+i);
 379 +    setnilvalue(L, fixed+i);
 380    }
 381    /* add `arg' parameter */
 382    if (htab) {
 383 @@ -294,7 +294,7 @@ int luaD_precall (lua_State *L, StkId fu
 384      ci->tailcalls = 0;
 385      ci->nresults = nresults;
 386      for (st = L->top; st < ci->top; st++)
 387 -      setnilvalue(st);
 388 +      setnilvalue(L, st);
 389      L->top = ci->top;
 390      if (L->hookmask & LUA_MASKCALL) {
 391        L->savedpc++;  /* hooks assume 'pc' is already incremented */
 392 @@ -354,8 +354,8 @@ int luaD_poscall (lua_State *L, StkId fi
 393    for (i = wanted; i != 0 && firstResult < L->top; i--)
 394      setobjs2s(L, res++, firstResult++);
 395    while (i-- > 0)
 396 -    setnilvalue(res++);
 397 -  L->top = res;
 398 +    setnilvalue(L, res++);
 399 +  setlvmtop(L, res);
 400    return (wanted - LUA_MULTRET);  /* 0 iff wanted == LUA_MULTRET */
 401  }
 402
 403 @@ -463,8 +463,12 @@ int luaD_pcall (lua_State *L, Pfunc func
 404    status = luaD_rawrunprotected(L, func, u);
 405    if (status != 0) {  /* an error occurred? */
 406      StkId oldtop = restorestack(L, old_top);
 407 +       StkId curtop = L->top;
 408 +    int i;
 409      luaF_close(L, oldtop);  /* close eventual pending closures */
 410      luaD_seterrorobj(L, status, oldtop);
 411 +    for (i = (curtop - L->top); i-- > 0;)
 412 +      setnilvalue(L, L->top + i);
 413      L->nCcalls = oldnCcalls;
 414      L->ci = restoreci(L, old_ci);
 415      L->base = L->ci->base;
 416 --- a/src/lfunc.c
 417 +++ b/src/lfunc.c
 418 @@ -17,7 +17,7 @@
 419  #include "lmem.h"
 420  #include "lobject.h"
 421  #include "lstate.h"
 422 -
 423 +#include "lvm.h"
 424
 425
 426  Closure *luaF_newCclosure (lua_State *L, int nelems, Table *e) {
 427 @@ -45,7 +45,7 @@ UpVal *luaF_newupval (lua_State *L) {
 428    UpVal *uv = luaM_new(L, UpVal);
 429    luaC_link(L, obj2gco(uv), LUA_TUPVAL);
 430    uv->v = &uv->u.value;
 431 -  setnilvalue(uv->v);
 432 +  setnilvalue(L, uv->v);
 433    return uv;
 434  }
 435
 436 @@ -67,8 +67,14 @@ UpVal *luaF_findupval (lua_State *L, Stk
 437    uv = luaM_new(L, UpVal);  /* not found: create a new one */
 438    uv->tt = LUA_TUPVAL;
 439    uv->marked = luaC_white(g);
 440 -  uv->v = level;  /* current value lives in the stack */
 441 +  uv->v = luaV_ref(level);  /* current value lives in the stack */
 442    uv->next = *pp;  /* chain it in the proper position */
 443 +  if (uv->next) {
 444 +       uv->prev = uv->next->gch.prev;
 445 +    uv->next->gch.prev = (GCObject *)uv;
 446 +  } else {
 447 +    uv->prev = NULL;
 448 +  }
 449    *pp = obj2gco(uv);
 450    uv->u.l.prev = &g->uvhead;  /* double link it in `uvhead' list */
 451    uv->u.l.next = g->uvhead.u.l.next;
 452 --- a/src/lgc.c
 453 +++ b/src/lgc.c
 454 @@ -21,6 +21,7 @@
 455  #include "lstring.h"
 456  #include "ltable.h"
 457  #include "ltm.h"
 458 +#include "lvm.h"
 459
 460
 461  #define GCSTEPSIZE     1024u
 462 @@ -265,7 +266,7 @@ static void traversestack (global_State
 463    for (o = l->stack; o < l->top; o++)
 464      markvalue(g, o);
 465    for (; o <= lim; o++)
 466 -    setnilvalue(o);
 467 +    setnilvalue(l, o);
 468    checkstacksizes(l, lim);
 469  }
 470
 471 @@ -348,7 +349,7 @@ static int iscleared (const TValue *o, i
 472  /*
 473  ** clear collected entries from weaktables
 474  */
 475 -static void cleartable (GCObject *l) {
 476 +static void cleartable (lua_State *L, GCObject *l) {
 477    while (l) {
 478      Table *h = gco2h(l);
 479      int i = h->sizearray;
 480 @@ -358,7 +359,7 @@ static void cleartable (GCObject *l) {
 481        while (i--) {
 482          TValue *o = &h->array[i];
 483          if (iscleared(o, 0))  /* value was collected? */
 484 -          setnilvalue(o);  /* remove value */
 485 +          setnilvalue(L, o);  /* remove value */
 486        }
 487      }
 488      i = sizenode(h);
 489 @@ -366,7 +367,7 @@ static void cleartable (GCObject *l) {
 490        Node *n = gnode(h, i);
 491        if (!ttisnil(gval(n)) &&  /* non-empty entry? */
 492            (iscleared(key2tval(n), 1) || iscleared(gval(n), 0))) {
 493 -        setnilvalue(gval(n));  /* remove value ... */
 494 +        setnilvalue(L, gval(n));  /* remove value ... */
 495          removeentry(n);  /* remove entry from table */
 496        }
 497      }
 498 @@ -375,7 +376,7 @@ static void cleartable (GCObject *l) {
 499  }
 500
 501
 502 -static void freeobj (lua_State *L, GCObject *o) {
 503 +void luaC_freeobj (lua_State *L, GCObject *o) {
 504    switch (o->gch.tt) {
 505      case LUA_TPROTO: luaF_freeproto(L, gco2p(o)); break;
 506      case LUA_TFUNCTION: luaF_freeclosure(L, gco2cl(o)); break;
 507 @@ -418,10 +419,12 @@ static GCObject **sweeplist (lua_State *
 508      }
 509      else {  /* must erase `curr' */
 510        lua_assert(isdead(g, curr) || deadmask == bitmask(SFIXEDBIT));
 511 +      if (curr->gch.next)
 512 +        curr->gch.next->gch.prev = curr->gch.prev;
 513        *p = curr->gch.next;
 514        if (curr == g->rootgc)  /* is the first element of the list? */
 515          g->rootgc = curr->gch.next;  /* adjust first */
 516 -      freeobj(L, curr);
 517 +      luaC_freeobj(L, curr);
 518      }
 519    }
 520    return p;
 521 @@ -543,7 +551,7 @@ static void atomic (lua_State *L) {
 522    udsize = luaC_separateudata(L, 0);  /* separate userdata to be finalized */
 523    marktmu(g);  /* mark `preserved' userdata */
 524    udsize += propagateall(g);  /* remark, to propagate `preserveness' */
 525 -  cleartable(g->weak);  /* remove collected objects from weak tables */
 526 +  cleartable(L, g->weak);  /* remove collected objects from weak tables */
 527    /* flip current white */
 528    g->currentwhite = cast_byte(otherwhite(g));
 529    g->sweepstrgc = 0;
 530 @@ -685,8 +693,11 @@ void luaC_barrierback (lua_State *L, Tab
 531
 532  void luaC_link (lua_State *L, GCObject *o, lu_byte tt) {
 533    global_State *g = G(L);
 534 +  o->gch.prev = (GCObject*)&g->rootgc;
 535    o->gch.next = g->rootgc;
 536    g->rootgc = o;
 537 +  if (o->gch.next)
 538 +    o->gch.next->gch.prev = o;
 539    o->gch.marked = luaC_white(g);
 540    o->gch.tt = tt;
 541  }
 542 --- a/src/lgc.h
 543 +++ b/src/lgc.h
 544 @@ -105,6 +105,6 @@ LUAI_FUNC void luaC_link (lua_State *L,
 545  LUAI_FUNC void luaC_linkupval (lua_State *L, UpVal *uv);
 546  LUAI_FUNC void luaC_barrierf (lua_State *L, GCObject *o, GCObject *v);
 547  LUAI_FUNC void luaC_barrierback (lua_State *L, Table *t);
 548 -
 549 +LUAI_FUNC void luaC_freeobj (lua_State *L, GCObject *o);
 550
 551  #endif
 552 --- a/src/lmem.c
 553 +++ b/src/lmem.c
 554 @@ -6,6 +6,7 @@
 555
 556
 557  #include <stddef.h>
 558 +#include <string.h>
 559
 560  #define lmem_c
 561  #define LUA_CORE
 562 @@ -80,6 +81,8 @@ void *luaM_realloc_ (lua_State *L, void
 563    if (block == NULL && nsize > 0)
 564      luaD_throw(L, LUA_ERRMEM);
 565    lua_assert((nsize == 0) == (block == NULL));
 566 +  if (nsize > osize)
 567 +    memset((char *)block + osize, 0, nsize - osize);
 568    g->totalbytes = (g->totalbytes - osize) + nsize;
 569    return block;
 570  }
 571 --- a/src/lobject.h
 572 +++ b/src/lobject.h
 573 @@ -44,7 +44,7 @@ typedef union GCObject GCObject;
 574  ** Common Header for all collectable objects (in macro form, to be
 575  ** included in other objects)
 576  */
 577 -#define CommonHeader   GCObject *next; lu_byte tt; lu_byte marked
 578 +#define CommonHeader   GCObject *next; GCObject *prev; lu_byte tt; lu_byte marked
 579
 580
 581  /*
 582 @@ -83,6 +83,7 @@ typedef struct lua_TValue {
 583    TValuefields;
 584  } TValue;
 585
 586 +#define tvinit() { .value.b = 0, .tt = 0 }
 587
 588  /* Macros to test type */
 589  #define ttisnil(o)     (ttype(o) == LUA_TNIL)
 590 @@ -145,15 +146,15 @@ typedef struct lua_TValue {
 591
 592
 593  /* Macros to set values */
 594 -#define setnilvalue(obj) ((obj)->tt=LUA_TNIL)
 595 +#define setnilvalue(L, obj) (luaV_unref(L, (obj))->tt=LUA_TNIL)
 596
 597  /* Must not have side effects, 'x' may be expression.
 598  */
 599  #define setivalue(obj,x) \
 600 -    { TValue *i_o=(obj); i_o->value.i=(x); i_o->tt=LUA_TINT; }
 601 +    { TValue *i_o=luaV_unref(L, (obj)); i_o->value.i=(x); i_o->tt=LUA_TINT; }
 602
 603  # define setnvalue(obj,x) \
 604 -    { TValue *i_o=(obj); i_o->value.n= (x); i_o->tt=LUA_TNUMBER; }
 605 +    { TValue *i_o=luaV_unref(L, (obj)); i_o->value.n= (x); i_o->tt=LUA_TNUMBER; }
 606
 607  /* Note: Complex always has "inline", both are C99.
 608  */
 609 @@ -170,45 +171,45 @@ typedef struct lua_TValue {
 610
 611
 612  #define setpvalue(obj,x) \
 613 -  { TValue *i_o=(obj); i_o->value.p=(x); i_o->tt=LUA_TLIGHTUSERDATA; }
 614 +  { TValue *i_o=luaV_unref(L, (obj)); i_o->value.p=(x); i_o->tt=LUA_TLIGHTUSERDATA; }
 615
 616  #define setbvalue(obj,x) \
 617 -  { TValue *i_o=(obj); i_o->value.b=(x); i_o->tt=LUA_TBOOLEAN; }
 618 +  { TValue *i_o=luaV_unref(L, (obj)); i_o->value.b=(x); i_o->tt=LUA_TBOOLEAN; }
 619
 620  #define setsvalue(L,obj,x) \
 621 -  { TValue *i_o=(obj); \
 622 -    i_o->value.gc=cast(GCObject *, (x)); i_o->tt=LUA_TSTRING; \
 623 +  { TValue *i_o=(obj); TString *val=(x); luaS_ref(val); luaV_unref(L, obj); \
 624 +    i_o->value.gc=cast(GCObject *, (val)); i_o->tt=LUA_TSTRING; \
 625      checkliveness(G(L),i_o); }
 626
 627  #define setuvalue(L,obj,x) \
 628 -  { TValue *i_o=(obj); \
 629 +  { TValue *i_o=luaV_unref(L, (obj)); \
 630      i_o->value.gc=cast(GCObject *, (x)); i_o->tt=LUA_TUSERDATA; \
 631      checkliveness(G(L),i_o); }
 632
 633  #define setthvalue(L,obj,x) \
 634 -  { TValue *i_o=(obj); \
 635 +  { TValue *i_o=luaV_unref(L, (obj)); \
 636      i_o->value.gc=cast(GCObject *, (x)); i_o->tt=LUA_TTHREAD; \
 637      checkliveness(G(L),i_o); }
 638
 639  #define setclvalue(L,obj,x) \
 640 -  { TValue *i_o=(obj); \
 641 +  { TValue *i_o=luaV_unref(L, (obj)); \
 642      i_o->value.gc=cast(GCObject *, (x)); i_o->tt=LUA_TFUNCTION; \
 643      checkliveness(G(L),i_o); }
 644
 645  #define sethvalue(L,obj,x) \
 646 -  { TValue *i_o=(obj); \
 647 +  { TValue *i_o=luaV_unref(L, (obj)); \
 648      i_o->value.gc=cast(GCObject *, (x)); i_o->tt=LUA_TTABLE; \
 649      checkliveness(G(L),i_o); }
 650
 651  #define setptvalue(L,obj,x) \
 652 -  { TValue *i_o=(obj); \
 653 +  { TValue *i_o=luaV_unref(L, (obj)); \
 654      i_o->value.gc=cast(GCObject *, (x)); i_o->tt=LUA_TPROTO; \
 655      checkliveness(G(L),i_o); }
 656
 657  #define setobj(L,obj1,obj2) \
 658 -  { const TValue *o2=(obj2); TValue *o1=(obj1); \
 659 +  do { const TValue *o2=luaV_ref((TValue *)(obj2)); TValue *o1=luaV_unref(L, (obj1)); \
 660      o1->value = o2->value; o1->tt=o2->tt; \
 661 -    checkliveness(G(L),o1); }
 662 +    checkliveness(G(L),o1); } while(0)
 663
 664
 665  /*
 666 @@ -253,6 +254,7 @@ typedef union TString {
 667      lu_byte reserved;
 668      unsigned int hash;
 669      size_t len;
 670 +    int refcount;
 671    } tsv;
 672  } TString;
 673
 674 @@ -409,6 +411,7 @@ typedef struct Table {
 675  #define twoto(x)       (1<<(x))
 676  #define sizenode(t)    (twoto((t)->lsizenode))
 677
 678 +#include "lstring.h"
 679
 680  #define luaO_nilobject         (&luaO_nilobject_)
 681
 682 --- a/src/lparser.c
 683 +++ b/src/lparser.c
 684 @@ -24,6 +24,7 @@
 685  #include "lstate.h"
 686  #include "lstring.h"
 687  #include "ltable.h"
 688 +#include "lvm.h"
 689
 690
 691
 692 @@ -146,7 +147,7 @@ static int registerlocalvar (LexState *l
 693    luaM_growvector(ls->L, f->locvars, fs->nlocvars, f->sizelocvars,
 694                    LocVar, SHRT_MAX, "too many local variables");
 695    while (oldsize < f->sizelocvars) f->locvars[oldsize++].varname = NULL;
 696 -  f->locvars[fs->nlocvars].varname = varname;
 697 +  f->locvars[fs->nlocvars].varname = luaS_ref(varname);
 698    luaC_objbarrier(ls->L, f, varname);
 699    return fs->nlocvars++;
 700  }
 701 @@ -194,7 +195,7 @@ static int indexupvalue (FuncState *fs,
 702    luaM_growvector(fs->L, f->upvalues, f->nups, f->sizeupvalues,
 703                    TString *, MAX_INT, "");
 704    while (oldsize < f->sizeupvalues) f->upvalues[oldsize++] = NULL;
 705 -  f->upvalues[f->nups] = name;
 706 +  f->upvalues[f->nups] = luaS_ref(name);
 707    luaC_objbarrier(fs->L, f, name);
 708    lua_assert(v->k == VLOCAL || v->k == VUPVAL);
 709    fs->upvalues[f->nups].k = cast_byte(v->k);
 710 @@ -341,7 +342,7 @@ static void open_func (LexState *ls, Fun
 711    fs->nlocvars = 0;
 712    fs->nactvar = 0;
 713    fs->bl = NULL;
 714 -  f->source = ls->source;
 715 +  f->source = luaS_ref(ls->source);
 716    f->maxstacksize = 2;  /* registers 0/1 are always valid */
 717    fs->h = luaH_new(L, 0, 0);
 718    /* anchor table of constants and prototype (to avoid being collected) */
 719 --- a/src/lstate.c
 720 +++ b/src/lstate.c
 721 @@ -22,6 +22,7 @@
 722  #include "lstring.h"
 723  #include "ltable.h"
 724  #include "ltm.h"
 725 +#include "lvm.h"
 726
 727
 728  #define state_size(x)  (sizeof(x) + LUAI_EXTRASPACE)
 729 @@ -52,7 +53,7 @@ static void stack_init (lua_State *L1, l
 730    L1->stack_last = L1->stack+(L1->stacksize - EXTRA_STACK)-1;
 731    /* initialize first ci */
 732    L1->ci->func = L1->top;
 733 -  setnilvalue(L1->top++);  /* `function' entry for this `ci' */
 734 +  setnilvalue(L1, L1->top++);  /* `function' entry for this `ci' */
 735    L1->base = L1->ci->base = L1->top;
 736    L1->ci->top = L1->top + LUA_MINSTACK;
 737  }
 738 @@ -98,7 +99,7 @@ static void preinit_state (lua_State *L,
 739    L->base_ci = L->ci = NULL;
 740    L->savedpc = NULL;
 741    L->errfunc = 0;
 742 -  setnilvalue(gt(L));
 743 +  setnilvalue(L, gt(L));
 744  }
 745
 746
 747 @@ -163,7 +164,7 @@ LUA_API lua_State *lua_newstate (lua_All
 748    g->strt.size = 0;
 749    g->strt.nuse = 0;
 750    g->strt.hash = NULL;
 751 -  setnilvalue(registry(L));
 752 +  setnilvalue(L, registry(L));
 753    luaZ_initbuffer(L, &g->buff);
 754    g->panic = NULL;
 755    g->gcstate = GCSpause;
 756 --- a/src/lstring.c
 757 +++ b/src/lstring.c
 758 @@ -37,6 +37,9 @@ void luaS_resize (lua_State *L, int news
 759        int h1 = lmod(h, newsize);  /* new position */
 760        lua_assert(cast_int(h%newsize) == lmod(h, newsize));
 761        p->gch.next = newhash[h1];  /* chain it */
 762 +      if (p->gch.next)
 763 +        p->gch.next->gch.prev = p;
 764 +      p->gch.prev = NULL;
 765        newhash[h1] = p;
 766        p = next;
 767      }
 768 @@ -59,11 +62,15 @@ static TString *newlstr (lua_State *L, c
 769    ts->tsv.marked = luaC_white(G(L));
 770    ts->tsv.tt = LUA_TSTRING;
 771    ts->tsv.reserved = 0;
 772 +  ts->tsv.refcount = 0;
 773    memcpy(ts+1, str, l*sizeof(char));
 774    ((char *)(ts+1))[l] = '\0';  /* ending 0 */
 775    tb = &G(L)->strt;
 776    h = lmod(h, tb->size);
 777    ts->tsv.next = tb->hash[h];  /* chain new entry */
 778 +  if (ts->tsv.next)
 779 +    ts->tsv.next->gch.prev = (GCObject *)ts;
 780 +  ts->tsv.prev = NULL;
 781    tb->hash[h] = obj2gco(ts);
 782    tb->nuse++;
 783    if (tb->nuse > cast(lu_int32, tb->size) && tb->size <= MAX_INT/2)
 784 @@ -109,3 +116,29 @@ Udata *luaS_newudata (lua_State *L, size
 785    return u;
 786  }
 787
 788 +void luaS_unref(lua_State *L, TString *ts) {
 789 +  if (!L || !ts)
 790 +    return;
 791 +  if (testbit(ts->tsv.marked, FIXEDBIT))
 792 +    return;
 793 +  ts->tsv.refcount--;
 794 +  if (ts->tsv.refcount < 0) {
 795 +    fprintf(stderr, "REFCOUNT BUG, COUNT=%d, str=%s, len=%d\n", ts->tsv.refcount, (char *) (ts + 1), (int) ts->tsv.len);
 796 +  } else if (ts->tsv.refcount)
 797 +    return;
 798 +
 799 +  if (ts->tsv.prev) {
 800 +    ts->tsv.prev->gch.next = ts->tsv.next;
 801 +  } else {
 802 +    unsigned int idx = lmod(ts->tsv.hash, G(L)->strt.size);
 803 +    lua_assert(G(L)->strt.hash[index] == (GCObject*)ts);
 804 +    G(L)->strt.hash[idx] = ts->tsv.next;
 805 +  }
 806 +
 807 +  if (ts->tsv.next)
 808 +    ts->tsv.next->gch.prev = ts->tsv.prev;
 809 +
 810 +  luaC_freeobj(L, (GCObject *) ts);
 811 +}
 812 +
 813 +
 814 --- a/src/lstring.h
 815 +++ b/src/lstring.h
 816 @@ -7,7 +7,7 @@
 817  #ifndef lstring_h
 818  #define lstring_h
 819
 820 -
 821 +#include <stdio.h>
 822  #include "lgc.h"
 823  #include "lobject.h"
 824  #include "lstate.h"
 825 @@ -23,6 +23,12 @@
 826
 827  #define luaS_fix(s)    l_setbit((s)->tsv.marked, FIXEDBIT)
 828
 829 +static inline TString *luaS_ref(TString *ts) {
 830 +  ts->tsv.refcount++;
 831 +  return ts;
 832 +}
 833 +
 834 +LUA_API void luaS_unref(lua_State *L, TString *ts);
 835  LUAI_FUNC void luaS_resize (lua_State *L, int newsize);
 836  LUAI_FUNC Udata *luaS_newudata (lua_State *L, size_t s, Table *e);
 837  LUA_API TString *luaS_newlstr (lua_State *L, const char *str, size_t l);
 838 --- a/src/ltable.c
 839 +++ b/src/ltable.c
 840 @@ -34,6 +34,7 @@
 841  #include "lstate.h"
 842  #include "ltable.h"
 843  #include "lnum.h"
 844 +#include "lvm.h"
 845
 846
 847  /*
 848 @@ -278,7 +279,7 @@ static void setarrayvector (lua_State *L
 849    int i;
 850    luaM_reallocvector(L, t->array, t->sizearray, size, TValue);
 851    for (i=t->sizearray; i<size; i++)
 852 -     setnilvalue(&t->array[i]);
 853 +     setnilvalue(L, &t->array[i]);
 854    t->sizearray = size;
 855  }
 856
 857 @@ -299,8 +300,8 @@ static void setnodevector (lua_State *L,
 858      for (i=0; i<size; i++) {
 859        Node *n = gnode(t, i);
 860        gnext(n) = NULL;
 861 -      setnilvalue(gkey(n));
 862 -      setnilvalue(gval(n));
 863 +      setnilvalue(L, gkey(n));
 864 +      setnilvalue(L, gval(n));
 865      }
 866    }
 867    t->lsizenode = cast_byte(lsize);
 868 @@ -427,9 +428,11 @@ static TValue *newkey (lua_State *L, Tab
 869          othern = gnext(othern);  /* find previous */
 870        }
 871        gnext(othern) = n;  /* redo the chain with `n' in place of `mp' */
 872 +      luaV_ref((TValue *) gkey(mp));
 873 +      luaV_ref(gval(mp));
 874        *n = *mp;  /* copy colliding node into free pos. (mp->next also goes) */
 875        gnext(mp) = NULL;  /* now `mp' is free */
 876 -      setnilvalue(gval(mp));
 877 +      setnilvalue(L, gval(mp));
 878      }
 879      else {  /* colliding node is in its own main position */
 880        /* new node will go into free position */
 881 @@ -438,6 +441,7 @@ static TValue *newkey (lua_State *L, Tab
 882        mp = n;
 883      }
 884    }
 885 +  luaV_ref((TValue *) key);
 886    gkey(mp)->value = key->value; gkey(mp)->tt = key->tt;
 887    luaC_barriert(L, t, key);
 888    lua_assert(ttisnil(gval(mp)));
 889 @@ -530,7 +534,7 @@ TValue *luaH_setint (lua_State *L, Table
 890    if (p != luaO_nilobject)
 891      return cast(TValue *, p);
 892    else {
 893 -    TValue k;
 894 +    TValue k = tvinit();
 895      setivalue(&k, key);
 896      return newkey(L, t, &k);
 897    }
 898 @@ -542,7 +546,7 @@ TValue *luaH_setstr (lua_State *L, Table
 899    if (p != luaO_nilobject)
 900      return cast(TValue *, p);
 901    else {
 902 -    TValue k;
 903 +    TValue k = tvinit();
 904      setsvalue(L, &k, key);
 905      return newkey(L, t, &k);
 906    }
 907 --- a/src/luac.c
 908 +++ b/src/luac.c
 909 @@ -20,8 +20,9 @@
 910  #include "lmem.h"
 911  #include "lobject.h"
 912  #include "lopcodes.h"
 913 -#include "lstring.h"
 914  #include "lundump.h"
 915 +#include "lvm.h"
 916 +#include "lstring.h"
 917
 918  #define PROGNAME       "luac"          /* default program name */
 919  #define        OUTPUT          PROGNAME ".out" /* default output file */
 920 --- a/src/lundump.c
 921 +++ b/src/lundump.c
 922 @@ -19,6 +19,7 @@
 923  #include "lstring.h"
 924  #include "lundump.h"
 925  #include "lzio.h"
 926 +#include "lvm.h"
 927
 928  typedef struct {
 929   lua_State* L;
 930 @@ -133,7 +134,7 @@ static TString* LoadString(LoadState* S)
 931   {
 932    char* s=luaZ_openspace(S->L,S->b,size);
 933    LoadBlock(S,s,size);
 934 -  return luaS_newlstr(S->L,s,size-1);          /* remove trailing '\0' */
 935 +  return luaS_ref(luaS_newlstr(S->L,s,size-1));                /* remove trailing '\0' */
 936   }
 937  }
 938
 939 @@ -149,11 +150,12 @@ static Proto* LoadFunction(LoadState* S,
 940
 941  static void LoadConstants(LoadState* S, Proto* f)
 942  {
 943 + lua_State *L = S->L;
 944   int i,n;
 945   n=LoadInt(S);
 946   f->k=luaM_newvector(S->L,n,TValue);
 947   f->sizek=n;
 948 - for (i=0; i<n; i++) setnilvalue(&f->k[i]);
 949 + for (i=0; i<n; i++) setnilvalue(L, &f->k[i]);
 950   for (i=0; i<n; i++)
 951   {
 952    TValue* o=&f->k[i];
 953 @@ -161,7 +163,7 @@ static void LoadConstants(LoadState* S,
 954    switch (t)
 955    {
 956     case LUA_TNIL:
 957 -       setnilvalue(o);
 958 +       setnilvalue(L, o);
 959         break;
 960     case LUA_TBOOLEAN:
 961         setbvalue(o,LoadChar(S)!=0);
 962 @@ -229,6 +231,7 @@ static Proto* LoadFunction(LoadState* S,
 963   LoadDebug(S,f);
 964   IF (!luaG_checkcode(f), "bad code");
 965   S->L->top--;
 966 + setnilvalue(S->L, S->L->top);
 967   S->L->nCcalls--;
 968   return f;
 969  }
 970 --- a/src/lvm.c
 971 +++ b/src/lvm.c
 972 @@ -39,6 +39,7 @@
 973   * If 'obj' is a string, it is tried to be interpreted as a number.
 974   */
 975  const TValue *luaV_tonumber ( const TValue *obj, TValue *n) {
 976 +  lua_State *L = NULL; /* FIXME */
 977    lua_Number d;
 978    lua_Integer i;
 979
 980 @@ -384,6 +386,7 @@ void luaV_concat (lua_State *L, int tota
 981          size_t l = tsvalue(top-i)->len;
 982          memcpy(buffer+tl, svalue(top-i), l);
 983          tl += l;
 984 +               setnilvalue(L, top - i);
 985        }
 986        setsvalue2s(L, top-n, luaS_newlstr(L, buffer, tl));
 987      }
 988 @@ -420,7 +423,7 @@ void luaV_concat (lua_State *L, int tota
 989   */
 990  static void Arith (lua_State *L, StkId ra, const TValue *rb,
 991                     const TValue *rc, TMS op) {
 992 -  TValue tempb, tempc;
 993 +  TValue tempb = tvinit(), tempc = tvinit();
 994    const TValue *b, *c;
 995    lua_Number nb,nc;
 996
 997 @@ -663,7 +666,7 @@ void luaV_execute (lua_State *L, int nex
 998        OPCODE_TARGET(LOADNIL) {
 999          TValue *rb = RB(i);
1000          do {
1001 -          setnilvalue(rb--);
1002 +          setnilvalue(L, rb--);
1003          } while (rb >= ra);
1004          continue;
1005        }
1006 @@ -673,7 +676,7 @@ void luaV_execute (lua_State *L, int nex
1007          continue;
1008        }
1009        OPCODE_TARGET(GETGLOBAL) {
1010 -        TValue g;
1011 +        TValue g = tvinit();
1012          TValue *rb = KBx(i);
1013          sethvalue(L, &g, cl->env);
1014          lua_assert(ttisstring(rb));
1015 @@ -685,7 +688,7 @@ void luaV_execute (lua_State *L, int nex
1016          continue;
1017        }
1018        OPCODE_TARGET(SETGLOBAL) {
1019 -        TValue g;
1020 +        TValue g = tvinit();
1021          sethvalue(L, &g, cl->env);
1022          lua_assert(ttisstring(KBx(i)));
1023          Protect(luaV_settable(L, &g, KBx(i), ra));
1024 @@ -895,7 +900,7 @@ void luaV_execute (lua_State *L, int nex
1025          if (--nexeccalls == 0)  /* was previous function running `here'? */
1026            return;  /* no: return */
1027          else {  /* yes: continue its execution */
1028 -          if (b) L->top = L->ci->top;
1029 +          if (b) setlvmtop(L, L->ci->top);
1030            lua_assert(isLua(L->ci));
1031            lua_assert(GET_OPCODE(*((L->ci)->savedpc - 1)) == OP_CALL);
1032            goto reentry;
1033 @@ -986,6 +991,7 @@ void luaV_execute (lua_State *L, int nex
1034          for (; n > 0; n--) {
1035            TValue *val = ra+n;
1036            setobj2t(L, luaH_setint(L, h, last--), val);
1037 +          setnilvalue(L, val);
1038            luaC_barriert(L, h, val);
1039          }
1040          continue;
1041 @@ -1030,7 +1036,7 @@ void luaV_execute (lua_State *L, int nex
1042              setobjs2s(L, ra + j, ci->base - n + j);
1043            }
1044            else {
1045 -            setnilvalue(ra + j);
1046 +            setnilvalue(L, ra + j);
1047            }
1048          }
1049          continue;
1050 --- a/src/lvm.h
1051 +++ b/src/lvm.h
1052 @@ -11,6 +11,7 @@
1053  #include "ldo.h"
1054  #include "lobject.h"
1055  #include "ltm.h"
1056 +#include "lstring.h"
1057
1058
1059  #define tostring(L,o) ((ttype(o) == LUA_TSTRING) || (luaV_tostring(L, o)))
1060 @@ -19,6 +20,19 @@
1061
1062  #define equalobj(L,o1,o2) (ttype_ext_same(o1,o2) && luaV_equalval(L, o1, o2))
1063
1064 +static inline TValue *luaV_ref(TValue *tv)
1065 +{
1066 +  if (ttisstring(tv))
1067 +    luaS_ref(rawtsvalue(tv));
1068 +  return tv;
1069 +}
1070 +
1071 +static inline TValue *luaV_unref(lua_State *L, TValue *tv)
1072 +{
1073 +  if (ttisstring(tv))
1074 +    luaS_unref(L, rawtsvalue(tv));
1075 +  return tv;
1076 +}
1077
1078  LUAI_FUNC int luaV_lessthan (lua_State *L, const TValue *l, const TValue *r);
1079  LUAI_FUNC int luaV_equalval (lua_State *L, const TValue *t1, const TValue *t2);
1080 --- a/src/llex.c
1081 +++ b/src/llex.c
1082 @@ -23,6 +23,7 @@
1083  #include "ltable.h"
1084  #include "lzio.h"
1085  #include "lnum.h"
1086 +#include "lvm.h"
1087
1088
1089
1090 @@ -69,7 +70,7 @@ static void save (LexState *ls, int c) {
1091  void luaX_init (lua_State *L) {
1092    int i;
1093    for (i=0; i<NUM_RESERVED; i++) {
1094 -    TString *ts = luaS_new(L, luaX_tokens[i]);
1095 +    TString *ts = luaS_ref(luaS_new(L, luaX_tokens[i]));
1096      luaS_fix(ts);  /* reserved words are never collected */
1097      lua_assert(strlen(luaX_tokens[i])+1 <= TOKEN_LEN);
1098      ts->tsv.reserved = cast_byte(i+1);  /* reserved word */
1099 @@ -125,7 +126,7 @@ void luaX_syntaxerror (LexState *ls, con
1100
1101  TString *luaX_newstring (LexState *ls, const char *str, size_t l) {
1102    lua_State *L = ls->L;
1103 -  TString *ts = luaS_newlstr(L, str, l);
1104 +  TString *ts = luaS_ref(luaS_newlstr(L, str, l));
1105    TValue *o = luaH_setstr(L, ls->fs->h, ts);  /* entry for `str' */
1106    if (ttisnil(o))
1107      setbvalue(o, 1);  /* make sure `str' will not be collected */
1108 @@ -152,7 +153,7 @@ void luaX_setinput (lua_State *L, LexSta
1109    ls->fs = NULL;
1110    ls->linenumber = 1;
1111    ls->lastline = 1;
1112 -  ls->source = source;
1113 +  ls->source = luaS_ref(source);
1114    luaZ_resizebuffer(ls->L, ls->buff, LUA_MINBUFFER);  /* initialize buffer */
1115    next(ls);  /* read first char */
1116  }
1117 --- a/src/lstate.h
1118 +++ b/src/lstate.h
1119 @@ -144,6 +144,13 @@ union GCObject {
1120    struct lua_State th;  /* thread */
1121  };
1122
1123 +#define setlvmtop(L, val) do { \
1124 +       int __i; \
1125 +       for (__i = L->top - val; __i-- > 0;) \
1126 +               setnilvalue(L, val + __i); \
1127 +       L->top = val; \
1128 +} while (0)
1129 +
1130
1131  /* macros to convert a GCObject into a specific value */
1132  #define rawgco2ts(o)   check_exp((o)->gch.tt == LUA_TSTRING, &((o)->ts))