PVS-Studio warning V586 for VNL

void testlib_register_test(const vcl_string & name,
                           TestMainFunction func)
{
  testlib_test_func_.push_back(func);
  testlib_test_name_.push_back(name);
}

void testlib_cleanup()
{
  testlib_test_func_.clear();
  testlib_test_func_.clear();
}

This suspicious code was found in VNL project by PVS-Studio static code analyzer.
Warning message is:
V586 The 'clear' function is called twice for deallocation of the same resource. Check lines: 202, 203. testlib_main.cxx 203

PVS-Studio is a static analyzer for detecting bugs in the source code of applications written in C, C++, C++11, C++/CX. Site: http://www.viva64.com/en/pvs-studio/