w.Header()[xhttp.ETag] = []string{"\"" + objInfo.ETag + "\""}
		}
	}
	// x-amz-copy-source-if-modified-since: Return the object only if it has been modified
	// since the specified time otherwise return 412 (precondition failed).
	ifModifiedSinceHeader := r.Header.Get(xhttp.AmzCopySourceIfModifiedSince)
	if ifModifiedSinceHeader != "" {
		if givenTime, err := amztime.ParseHeader(ifModifiedSinceHeader); err == nil {

	if c.TraceOutput != nil && resp.StatusCode != http.StatusOK {
		c.dumpHTTP(req, resp)
	}

	if resp.StatusCode != http.StatusOK {
		// If server returns 412 pre-condition failed, it would
		// mean that authentication succeeded, but another
		// side-channel check has failed, we shall take
		// the client offline in such situations.

func stack404()  { var buf [404]byte; use(buf[:]); C.callGoStackCheck() }
func stack408()  { var buf [408]byte; use(buf[:]); C.callGoStackCheck() }
func stack412()  { var buf [412]byte; use(buf[:]); C.callGoStackCheck() }
func stack416()  { var buf [416]byte; use(buf[:]); C.callGoStackCheck() }
func stack420()  { var buf [420]byte; use(buf[:]); C.callGoStackCheck() }

// If-Unmodified-Since - Return the object only if it has not been modified since the specified time, else return a 412 (precondition failed).
func (s *TestSuiteCommon) TestHeadOnObjectLastModified(c *check) {
	// generate a random bucket name.
	bucketName := getRandomBucketName()
	// HTTP request to create the bucket.