sO callWithVarargs_sentinel(O o, S methodName, O methodNotFoundSentinel, O... args) ctex {
  if (o == null) null;
  
  if (o instanceof Class) {
    Class c = (Class) o;
    _MethodCache cache = callOpt_getCache(c);
    
    Method me = cache.findStaticMethod(methodName, args);
    if (me != null)
      ret invokeMethod(me, null, args);
      
    // try varargs
    L<Method> methods = cache.cache.get(methodName);
    if (methods != null) methodSearch: for (Method m : methods) {
      continue unless m.isVarArgs();
      continue unless isStaticMethod(m);
      O[] newArgs = massageArgsForVarArgsCall(m, args);
      if (newArgs != null)
        ret invokeMethod(m, null, newArgs);
    }
    
    methodNotFoundSentinel;
  } else {
    Class c = o.getClass();
    _MethodCache cache = callOpt_getCache(c);

    Method me = cache.findMethod(methodName, args);
    if (me != null)
      ret invokeMethod(me, o, args);
      
    // try varargs
    L<Method> methods = cache.cache.get(methodName);
    if (methods != null) methodSearch: for (Method m : methods) {
      continue unless m.isVarArgs();
      O[] newArgs = massageArgsForVarArgsCall(m, args);
      if (newArgs != null)
        ret invokeMethod(m, o, newArgs);
    }
    
    methodNotFoundSentinel;
  }
}

Began life as a copy of #1022095