diff --git a/lfunc.c b/lfunc.c
index daa430c6..4ed1fcb9 100644
--- a/lfunc.c
+++ b/lfunc.c
@@ -1,5 +1,5 @@
 /*
-** $Id: lfunc.c,v 2.20 2010/03/12 19:14:06 roberto Exp roberto $
+** $Id: lfunc.c,v 2.21 2010/03/26 20:58:11 roberto Exp roberto $
 ** Auxiliary functions to manipulate prototypes and closures
 ** See Copyright Notice in lua.h
 */
@@ -96,10 +96,16 @@ void luaF_close (lua_State *L, StkId level) {
     if (isdead(g, o))
       luaF_freeupval(L, uv);  /* free upvalue */
     else {
-      unlinkupval(uv);
-      setobj(L, &uv->u.value, uv->v);
+      unlinkupval(uv);  /* remove upvalue from 'uvhead' list */
+      setobj(L, &uv->u.value, uv->v);  /* move value to upvalue slot */
       uv->v = &uv->u.value;  /* now current value lives here */
-      luaC_linkupval(L, uv);  /* link upvalue into `gcroot' list */
+      gch(o)->next = g->allgc;  /* link upvalue into 'allgc' list */
+      g->allgc = o;
+      lua_assert(!isblack(o));  /* open upvalues are never black */
+      if (isgray(o)) {  /* is it marked? */
+        gray2black(o);  /* could not be black; now it can */
+        luaC_barrier(L, uv, uv->v);
+      }
     }
   }
 }