Fix stack check when recording BC_VARG.

Contributed by Yichun Zhang.

src/lj_record.c

@@ -1602,6 +1602,8 @@ static void rec_varg(jit_State *J, BCReg dst, ptrdiff_t nresults)
       lj_trace_err_info(J, LJ_TRERR_NYIBC);
     }
   }
+  if (J->baseslot + J->maxslot >= LJ_MAX_JSLOTS)
+    lj_trace_err(J, LJ_TRERR_STACKOV);
 }
 
 /* -- Record allocations -------------------------------------------------- */