diff --git a/src/lj_state.c b/src/lj_state.c
index fc543c54..0c2c0750 100644
--- a/src/lj_state.c
+++ b/src/lj_state.c
@@ -72,7 +72,7 @@ static void resizestack(lua_State *L, MSize n)
   while (oldsize < realsize)  /* Clear new slots. */
     setnilV(st + oldsize++);
   L->stacksize = realsize;
-  if ((size_t)(mref(G(L)->jit_base, char) - (char *)oldst) < oldsize)
+  if ((size_t)(mref(G(L)->jit_base, char) - (char *)oldst) < (size_t)oldsize * sizeof(TValue))
     setmref(G(L)->jit_base, mref(G(L)->jit_base, char) + delta);
   L->base = (TValue *)((char *)L->base + delta);
   L->top = (TValue *)((char *)L->top + delta);