In some cases, you may need to override the default universe domain used by the client library. Use AddUniverseDomainOption when initializing the client library to change this default.
namespace gcs = ::google::cloud::storage;
[](std::string const& bucket_name, std::string const& object_name) {
google::cloud::Options options;
// AddUniverseDomainOption interrogates the UnifiedCredentialsOption, if
// set, in the provided Options for the Universe Domain associated with the
// credentials and adds it to the set of Options.
// If no UnifiedCredentialsOption is set, GoogleDefaultCredentials are used.
auto ud_options =
google::cloud::AddUniverseDomainOption(std::move(options));
if (!ud_options.ok()) throw std::move(ud_options).status();
auto client = gcs::Client(*ud_options);
PerformSomeOperations(client, bucket_name, object_name);
}