diff --git a/ldo.c b/ldo.c
index f282a773..a48e35f9 100644
--- a/ldo.c
+++ b/ldo.c
@@ -530,10 +530,10 @@ int luaD_pretailcall (lua_State *L, CallInfo *ci, StkId func,
       int fsize = p->maxstacksize;  /* frame size */
       int nfixparams = p->numparams;
       int i;
+      checkstackGCp(L, fsize - delta, func);
       ci->func -= delta;  /* restore 'func' (if vararg) */
       for (i = 0; i < narg1; i++)  /* move down function and arguments */
         setobjs2s(L, ci->func + i, func + i);
-      checkstackGC(L, fsize);
       func = ci->func;  /* moved-down function */
       for (; narg1 <= nfixparams; narg1++)
         setnilvalue(s2v(func + narg1));  /* complete missing arguments */