diff --git a/lcode.c b/lcode.c
index 3c39d0ce..16f5702a 100644
--- a/lcode.c
+++ b/lcode.c
@@ -1,5 +1,5 @@
 /*
-** $Id: lcode.c,v 2.60 2011/08/30 16:26:41 roberto Exp roberto $
+** $Id: lcode.c,v 2.61 2012/08/14 18:12:34 roberto Exp roberto $
 ** Code generator for Lua
 ** See Copyright Notice in lua.h
 */
@@ -330,10 +330,9 @@ int luaK_numberK (FuncState *fs, lua_Number r) {
   setnvalue(&o, r);
   if (r == 0 || luai_numisnan(NULL, r)) {  /* handle -0 and NaN */
     /* use raw representation as key to avoid numeric problems */
-    setsvalue(L, L->top, luaS_newlstr(L, (char *)&r, sizeof(r)));
-     incr_top(L);
-     n = addk(fs, L->top - 1, &o);
-     L->top--;
+    setsvalue(L, L->top++, luaS_newlstr(L, (char *)&r, sizeof(r)));
+    n = addk(fs, L->top - 1, &o);
+    L->top--;
   }
   else
     n = addk(fs, &o, &o);  /* regular case */
diff --git a/ldebug.c b/ldebug.c
index 431acc1f..5624be1d 100644
--- a/ldebug.c
+++ b/ldebug.c
@@ -1,5 +1,5 @@
 /*
-** $Id: ldebug.c,v 2.88 2011/11/30 12:43:51 roberto Exp roberto $
+** $Id: ldebug.c,v 2.89 2012/01/20 22:05:50 roberto Exp roberto $
 ** Debug Interface
 ** See Copyright Notice in lua.h
 */
@@ -196,7 +196,7 @@ static void funcinfo (lua_Debug *ar, Closure *cl) {
 static void collectvalidlines (lua_State *L, Closure *f) {
   if (noLuaClosure(f)) {
     setnilvalue(L->top);
-    incr_top(L);
+    api_incr_top(L);
   }
   else {
     int i;
@@ -204,7 +204,7 @@ static void collectvalidlines (lua_State *L, Closure *f) {
     int *lineinfo = f->l.p->lineinfo;
     Table *t = luaH_new(L);  /* new table to store active lines */
     sethvalue(L, L->top, t);  /* push it on stack */
-    incr_top(L);
+    api_incr_top(L);
     setbvalue(&v, 1);  /* boolean 'true' to be the value of all indices */
     for (i = 0; i < f->l.p->sizelineinfo; i++)  /* for all lines with code */
       luaH_setint(L, t, lineinfo[i], &v);  /* table[line] = true */
@@ -285,7 +285,7 @@ LUA_API int lua_getinfo (lua_State *L, const char *what, lua_Debug *ar) {
   status = auxgetinfo(L, what, ar, cl, ci);
   if (strchr(what, 'f')) {
     setobjs2s(L, L->top, func);
-    incr_top(L);
+    api_incr_top(L);
   }
   if (strchr(what, 'L'))
     collectvalidlines(L, cl);
@@ -563,7 +563,7 @@ l_noret luaG_errormsg (lua_State *L) {
     if (!ttisfunction(errfunc)) luaD_throw(L, LUA_ERRERR);
     setobjs2s(L, L->top, L->top - 1);  /* move argument */
     setobjs2s(L, L->top - 1, errfunc);  /* push function */
-    incr_top(L);
+    L->top++;
     luaD_call(L, L->top - 2, 1, 0);  /* call it */
   }
   luaD_throw(L, LUA_ERRRUN);
diff --git a/lobject.c b/lobject.c
index 86b3097e..11be7ad9 100644
--- a/lobject.c
+++ b/lobject.c
@@ -1,5 +1,5 @@
 /*
-** $Id: lobject.c,v 2.54 2011/11/30 12:44:26 roberto Exp roberto $
+** $Id: lobject.c,v 2.55 2011/11/30 19:30:16 roberto Exp roberto $
 ** Some generic functions over Lua objects
 ** See Copyright Notice in lua.h
 */
@@ -171,8 +171,7 @@ int luaO_str2d (const char *s, size_t len, lua_Number *result) {
 
 
 static void pushstr (lua_State *L, const char *str, size_t l) {
-  setsvalue2s(L, L->top, luaS_newlstr(L, str, l));
-  incr_top(L);
+  setsvalue2s(L, L->top++, luaS_newlstr(L, str, l));
 }
 
 
@@ -182,8 +181,8 @@ const char *luaO_pushvfstring (lua_State *L, const char *fmt, va_list argp) {
   for (;;) {
     const char *e = strchr(fmt, '%');
     if (e == NULL) break;
-    setsvalue2s(L, L->top, luaS_newlstr(L, fmt, e-fmt));
-    incr_top(L);
+    luaD_checkstack(L, 2);  /* fmt + item */
+    pushstr(L, fmt, e - fmt);
     switch (*(e+1)) {
       case 's': {
         const char *s = va_arg(argp, char *);
@@ -198,13 +197,11 @@ const char *luaO_pushvfstring (lua_State *L, const char *fmt, va_list argp) {
         break;
       }
       case 'd': {
-        setnvalue(L->top, cast_num(va_arg(argp, int)));
-        incr_top(L);
+        setnvalue(L->top++, cast_num(va_arg(argp, int)));
         break;
       }
       case 'f': {
-        setnvalue(L->top, cast_num(va_arg(argp, l_uacNumber)));
-        incr_top(L);
+        setnvalue(L->top++, cast_num(va_arg(argp, l_uacNumber)));
         break;
       }
       case 'p': {
@@ -226,6 +223,7 @@ const char *luaO_pushvfstring (lua_State *L, const char *fmt, va_list argp) {
     n += 2;
     fmt = e+2;
   }
+  luaD_checkstack(L, 1);
   pushstr(L, fmt, strlen(fmt));
   if (n > 0) luaV_concat(L, n + 1);
   return svalue(L->top - 1);
diff --git a/ltests.c b/ltests.c
index 610af463..1bbeac1c 100644
--- a/ltests.c
+++ b/ltests.c
@@ -1,5 +1,5 @@
 /*
-** $Id: ltests.c,v 2.131 2012/07/02 15:38:36 roberto Exp roberto $
+** $Id: ltests.c,v 2.132 2012/07/04 15:52:38 roberto Exp roberto $
 ** Internal Module for Debugging of the Lua Implementation
 ** See Copyright Notice in lua.h
 */
@@ -753,7 +753,7 @@ static int string_query (lua_State *L) {
     int n = 0;
     for (ts = tb->hash[s]; ts; ts = gch(ts)->next) {
       setsvalue2s(L, L->top, rawgco2ts(ts));
-      incr_top(L);
+      api_incr_top(L);
       n++;
     }
     return n;
diff --git a/lvm.c b/lvm.c
index 8657ebbe..db8c93ba 100644
--- a/lvm.c
+++ b/lvm.c
@@ -1,5 +1,5 @@
 /*
-** $Id: lvm.c,v 2.152 2012/06/08 15:14:04 roberto Exp roberto $
+** $Id: lvm.c,v 2.153 2012/08/14 18:12:34 roberto Exp roberto $
 ** Lua virtual machine
 ** See Copyright Notice in lua.h
 */
@@ -98,7 +98,6 @@ static void callTM (lua_State *L, const TValue *f, const TValue *p1,
   setobj2s(L, L->top++, p2);  /* 2nd argument */
   if (!hasres)  /* no result? 'p3' is third argument */
     setobj2s(L, L->top++, p3);  /* 3rd argument */
-  luaD_checkstack(L, 0);
   /* metamethod may yield only when called from Lua code */
   luaD_call(L, L->top - (4 - hasres), hasres, isLua(L->ci));
   if (hasres) {  /* if has result, move it to its place */