It would be nice if there was a way to tell compilers not to drop the lock stack and thus issue warnings when accessing a symbol that needs a lock inside `Assume`/`Assert`.

Hit by (at least): @ajtowns , @jnewbery , me.
{
    const char *str_config =
       "a=\n"
       "b=1\n"
       "ccc=argument\n"
       "ccc=multiple\n"
       "d=e\n"
       "nofff=1\n"
       "noggg=0\n"
       "h=1\n"
       "noh=1\n"
       "noi=1\n"
       "i=1\n"
       "sec1.ccc=extend1\n"
       "\n"
       "[sec1]\n"
       "ccc=extend2\n"
       "d=eee\n"
       "h=1\n"
       "[sec2]\n"
       "ccc=extend3\n"
       "iii=2\n";
    TestArgsManager test_args;
    LOCK(test_args.cs_args);
    const auto a = std::make_pair("-a", ArgsManager::ALLOW_ANY);
    const auto b = std::make_pair("-b", ArgsManager::ALLOW_ANY);
    const auto ccc = std::make_pair("-ccc", ArgsManager::ALLOW_ANY);