i have the latest Xcode and macOS installed
this is the error log :

  undefined symbols for architecture armv7:
  "std::__1::basic_string::__grow_by(unsigned long, unsigned long, unsigned long, unsigned long, unsigned long, unsigned long)", referenced from:
      std::__1::enable_if::type std::__1::basic_string::assign(char*, char*) in librholib.a(HttpServer.o)
      std::__1::enable_if::type std::__1::basic_string::assign(char const*, char const*) in librholib.a(HttpServer.o)
  "std::__1::basic_string::replace(unsigned long, unsigned long, char const*)", referenced from:
      rho::common::CFilePath::normalizePath(std::__1::basic_string const&) in librholib.a(HttpServer.o)
  "std::__1::__basic_string_common::__throw_length_error() const", referenced from:
      std::__1::enable_if::type std::__1::basic_string::__init(char*, char*) in librholib.a(CURLNetRequest.o)
      std::__1::enable_if::type std::__1::basic_string::__init(char const*, char const*) in librholib.a(HttpServer.o)
  "void std::__1::__sort(int*, int*, std::__1::__less&)", referenced from:
      rho::common::CAppCallbacksQueue::processCommand(rho::common::CThreadQueue::IQueueCommand*) in librholib.a(RhodesApp.o)
  "std::__1::basic_string::rfind(char, unsigned long) const", referenced from:
      rho::net::URI::getLastNamePart() in librholib.a(URI.o)
      rho::sync::CSyncSource::makeFileName(rho::sync::CAttrValue const&) in librhosynclib.a(SyncSource.o)
  "std::__1::basic_string::append(char const*)", referenced from:
      rho::LogMessage::flushLog() in librholib.a(RhoLog.o)
      rho::common::CFilePath::makeFullPath(char const*) in librholib.a(RhoLogConf.o)
      rho::common::RhoSettings::saveChangesToString(std::__1::basic_string&) in librholib.a(RhoConf.o)
      rho::net::toHexString(int, std::__1::basic_string&, int) in librholib.a(URI.o)
      rho::common::CRhodesApp::initAppUrls() in librholib.a(RhodesApp.o)
      rho::common::CRhodesApp::initHttpServer() in librholib.a(RhodesApp.o)
      rho::common::CRhodesApp::callCameraCallback(std::__1::basic_string, std::__1::basic_string const&, std::__1::basic_string const&, bool) in librholib.a(RhodesApp.o)
      ...
  "std::__1::basic_string::compare(char const*) const", referenced from:
      rho::LogMessage::isEnabled() const in librholib.a(RhoLog.o)
      rho::LogSettings::initRemoteLog() in librholib.a(RhoLogConf.o)
      rho::common::callback_enable_status_popup(void*, std::__1::basic_string const&) in librholib.a(RhodesApp.o)
      rho::common::callback_set_threaded_mode(void*, std::__1::basic_string const&) in librholib.a(RhodesApp.o)
      rho::common::callback_set_ssl_verify_peer(void*, std::__1::basic_string const&) in librholib.a(RhodesApp.o)
      rho::common::CRhodesApp::setPushNotification(std::__1::basic_string const&, std::__1::basic_string const&, std::__1::basic_string const&) in librholib.a(RhodesApp.o)
      _rho_rhodesapp_canstartapp in librholib.a(RhodesApp.o)
      ...
  "std::__1::basic_string::basic_string(std::__1::basic_string const&)", referenced from:
      rho::common::CRhoFile::recursiveCreateDir(char const*, char const*) in librholib.a(RhoFile.o)
      rho::LogMessage::LogMessage(char const*, int, int, rho::LogSettings&, rho::LogCategory const&) in librholib.a(RhoLog.o)
      rho::LogMessage::LogMessage(char const*, int, int, rho::LogSettings&, rho::LogCategory const&, bool) in librholib.a(RhoLog.o)
      rho::LogSettings::setExcludeFilter(std::__1::basic_string const&) in librholib.a(RhoLogConf.o)
      rho::Vector::addElement(std::__1::basic_string const&) in librholib.a(RhoLogConf.o)
      void std::__1::vector::__push_back_slow_path(std::__1::basic_string const&) in librholib.a(RhoLogConf.o)
      std::__1::vector::__swap_out_circular_buffer(std::__1::__split_buffer&) in librholib.a(RhoLogConf.o)
      ...
  "std::__1::basic_string::at(unsigned long) const", referenced from:
      rho::net::URI::urlEncode(std::__1::basic_string const&, std::__1::basic_string&) in librholib.a(URI.o)
      rho::common::CRhodesAppBase::canonicalizeRhoUrl(std::__1::basic_string const&) const in librholib.a(RhodesAppBase.o)
  "std::__1::basic_string::push_back(char)", referenced from:
      std::__1::basic_string std::__1::operator+(std::__1::basic_string const&, char) in librholib.a(RhoFile.o)
      rho::CLogFileSink::saveLogPosition() in librholib.a(RhoLogSink.o)
      rho::net::URI::urlEncode(std::__1::basic_string const&, std::__1::basic_string&) in librholib.a(URI.o)
      rho::net::URI::urlDecode(std::__1::basic_string const&, std::__1::basic_string&) in librholib.a(URI.o)
      rho::net::curlHeaderCallback(void*, unsigned long, unsigned long, void*) in librholib.a(CURLNetRequest.o)
      rho::net::CHttpServer::isIndex(std::__1::basic_string const&) in librholib.a(HttpServer.o)
      rho::net::CHttpServer::register_uri(std::__1::basic_string const&, void (* const&)(void*, std::__1::basic_string const&)) in librholib.a(HttpServer.o)
      ...
  "std::__1::basic_string::find(char, unsigned long) const", referenced from:
      rho::common::CTokenizer::nextToken() in librholib.a(Tokenizer.o)
      rho::common::CTokenizer::eatDelimeters() in librholib.a(Tokenizer.o)
      rho::net::curlHeaderCallback(void*, unsigned long, unsigned long, void*) in librholib.a(CURLNetRequest.o)
      rho::common::CFilePath::normalizePath(std::__1::basic_string const&) in librholib.a(HttpServer.o)
      _rho_sys_set_push_notification in librholib.a(System.o)
      rho::common::CSplashScreen::init() in librholib.a(SplashScreen.o)
      rho::common::map::Annotation::make_url(std::__1::basic_string const&, bool, double, double) in librholib.a(MapEngine.o)
      ...
  "std::__1::basic_string::__init(char const*, unsigned long, unsigned long)", referenced from:
      std::__1::basic_string std::__1::operator+(std::__1::basic_string const&, std::__1::basic_string const&) in librholib.a(RhoFile.o)
      std::__1::basic_string std::__1::operator+(std::__1::basic_string const&, char) in librholib.a(RhoFile.o)
      std::__1::basic_string std::__1::operator+(std::__1::basic_string const&, char const*) in librholib.a(RhoLogSink.o)
      std::__1::basic_string std::__1::operator+(char const*, std::__1::basic_string const&) in librholib.a(RhodesApp.o)
  "std::__1::basic_string::at(unsigned long)", referenced from:
      rho::common::CTokenizer::nextToken() in librholib.a(Tokenizer.o)
      rho::common::CTokenizer::eatDelimeters() in librholib.a(Tokenizer.o)
      rho::sync::CSyncEngine::doSearch(rho::Vector&, std::__1::basic_string, std::__1::basic_string, bool, int) in librhosynclib.a(SyncEngine.o)
      rho::sync::CSyncSource::makeFileName(rho::sync::CAttrValue const&) in librhosynclib.a(SyncSource.o)
  "std::__1::basic_string::append(char const*, unsigned long)", referenced from:
      std::__1::basic_string std::__1::operator+(std::__1::basic_string const&, std::__1::basic_string const&) in librholib.a(RhoFile.o)
      rho::LogMessage::addMessage(std::__1::basic_string) in librholib.a(RhoLog.o)
      std::__1::basic_string std::__1::operator+(std::__1::basic_string const&, char const*) in librholib.a(RhoLogSink.o)
      _rhoPlainLogData in librholib.a(RhoPlainLog.o)
      rho::common::RhoSettings::saveChangesToString(std::__1::basic_string&) in librholib.a(RhoConf.o)
      rho::net::URI::urlEncode(std::__1::basic_string const&, std::__1::basic_string&) in librholib.a(URI.o)
      rho::common::CAppCallbacksQueue::callCallback(std::__1::basic_string const&) in librholib.a(RhodesApp.o)
      ...
  "std::__1::basic_string::__init(char const*, unsigned long)", referenced from:
      rho::common::CRhoFile::recursiveCreateDir(char const*, char const*) in librholib.a(RhoFile.o)
      rho::LogMessage& rho::LogMessage::operator+(char const&) in librholib.a(RhoLog.o)
      rho::LogMessage& rho::LogMessage::operator+(char const (&) [2]) in librholib.a(RhoLog.o)
      rho::common::CLocalTime::toString(bool, bool) in librholib.a(RhoLog.o)
      rho::LogMessage& rho::LogMessage::operator+(unsigned int const&) in librholib.a(RhoLog.o)
      rho::LogMessage& rho::LogMessage::operator+(char const (&) [3]) in librholib.a(RhoLog.o)
      __GLOBAL__sub_I_RhoLog.cpp in librholib.a(RhoLog.o)
      ...
  "std::__1::__vector_base_common::__throw_length_error() const", referenced from:
      void std::__1::vector::__push_back_slow_path(std::__1::basic_string const&) in librholib.a(RhoLogConf.o)
      std::__1::vector::insert(std::__1::__wrap_iter, int const&) in librholib.a(RhodesApp.o)
      void std::__1::vector::__push_back_slow_path(rho::net::HttpHeader const&) in librholib.a(RhodesApp.o)
      void std::__1::vector::__push_back_slow_path(rho::ICallbackObject* const&) in librholib.a(RhodesApp.o)
      void std::__1::vector::__push_back_slow_path(int const&) in librholib.a(RhodesApp.o)
      void std::__1::vector::__push_back_slow_path(char const&) in librholib.a(CURLNetRequest.o)
      std::__1::enable_if::type std::__1::vector::assign(char*, char*) in librholib.a(CURLNetRequest.o)
      ...
  "std::__1::__vector_base_common::__throw_out_of_range() const", referenced from:
      _rho_conf_get_conflicts in librholib.a(RhoLogConf.o)
      rho::common::CAppCallbacksQueue::processCommand(rho::common::CThreadQueue::IQueueCommand*) in librholib.a(RhodesApp.o)
      rho::common::CRhodesApp::addCallbackObject(rho::ICallbackObject*, std::__1::basic_string) in librholib.a(RhodesApp.o)
      rho::common::CRhodesApp::getCallbackObject(int) in librholib.a(RhodesApp.o)
      rho::net::CAsyncHttp::cancelRequest(char const*) in librholib.a(AsyncHttp.o)
      rho::VectorPtr::removeElementAt(int, bool) in librholib.a(AsyncHttp.o)
      rho::common::CThreadQueue::isAlreadyExist(rho::common::CThreadQueue::IQueueCommand*) in librholib.a(ThreadQueue.o)
      ...
  "std::__1::basic_string::operator=(std::__1::basic_string const&)", referenced from:
      rho::common::CRhoFile::recursiveCreateDir(char const*, char const*) in librholib.a(RhoFile.o)
      rho::common::CFilePath::join(std::__1::basic_string const&, std::__1::basic_string const&) in librholib.a(RhoFile.o)
      rho::LogMessage::addPrefix(char const*, int) in librholib.a(RhoLog.o)
      rho::LogSettings::initRemoteLog() in librholib.a(RhoLogConf.o)
      rho::LogSettings::setLogFilePath(std::__1::basic_string const&) in librholib.a(RhoLogConf.o)
      rho::CLogSocketSink::CLogSocketSink(rho::LogSettings const&) in librholib.a(RhoLogSink.o)
      rho::common::RhoSettings::saveToFile(char const*, bool) in librholib.a(RhoConf.o)
      ...
  "std::__1::basic_string::assign(char const*, unsigned long)", referenced from:
      rho::net::CURLNetResponseImpl::CURLNetResponseImpl(char const*, unsigned long, int) in librholib.a(CURLNetRequest.o)
  "std::__1::basic_string::resize(unsigned long, char)", referenced from:
      rho::common::CRhoFile::readString(std::__1::basic_string&) in librholib.a(RhoFile.o)
  "std::__1::basic_string::basic_string(std::__1::basic_string const&, unsigned long, unsigned long, std::__1::allocator const&)", referenced from:
      rho::common::CRhoFile::recursiveCreateDir(char const*, char const*) in librholib.a(RhoFile.o)
      rho::common::CFilePath::join(std::__1::basic_string const&, std::__1::basic_string const&) in librholib.a(RhoFile.o)
      rho::LogSettings::setExcludeFilter(std::__1::basic_string const&) in librholib.a(RhoLogConf.o)
      rho::common::CTokenizer::nextToken() in librholib.a(Tokenizer.o)
      rho::net::URI::getLastNamePart() in librholib.a(URI.o)
      rho::net::URI::urlEncode(std::__1::basic_string const&, std::__1::basic_string&) in librholib.a(URI.o)
      rho::common::callback_redirect_to(void*, std::__1::basic_string const&) in librholib.a(RhodesApp.o)
      ...
  "std::__1::basic_string::assign(char const*)", referenced from:
      rho::common::CRhoFile::open(char const*, rho::common::CRhoFile::EOpenModes) in librholib.a(RhoFile.o)
      rho::common::CRhoFile::loadTextFile(char const*, std::__1::basic_string&) in librholib.a(RhoFile.o)
      rho::common::CRhoFile::readStringFromFile(char const*, std::__1::basic_string&) in librholib.a(RhoFile.o)
      rho::common::CRhoFile::writeStringToFile(char const*, std::__1::basic_string&) in librholib.a(RhoFile.o)
      rho::common::CRhoFile::copyFile(char const*, char const*) in librholib.a(RhoFile.o)
      rho::LogSettings::LogSettings() in librholib.a(RhoLogConf.o)
      rho::LogSettings::setEnabledCategories(char const*) in librholib.a(RhoLogConf.o)
      ...
  "_MotorolaLicence_check", referenced from:
      _rho_can_app_started_with_current_licence in librholib.a(RhodesApp.o)
  "std::__1::basic_string::erase(unsigned long, unsigned long)", referenced from:
      rho::LogMessage::applyExcludeFilter(std::__1::basic_string&) in librholib.a(RhoLog.o)
      rho::CLogOutputSink::writeLogMessage(std::__1::basic_string&) in librholib.a(RhoLogSink.o)
  "std::__1::basic_string::~basic_string()", referenced from:
      rho::common::CRhoFile::recursiveCreateDir(char const*, char const*) in librholib.a(RhoFile.o)
      rho::common::CFilePath::join(std::__1::basic_string const&, std::__1::basic_string const&) in librholib.a(RhoFile.o)
      std::__1::basic_string std::__1::operator+(std::__1::basic_string const&, std::__1::basic_string const&) in librholib.a(RhoFile.o)
      std::__1::basic_string std::__1::operator+(std::__1::basic_string const&, char) in librholib.a(RhoFile.o)
      rho::common::CRhoFile::~CRhoFile() in librholib.a(RhoFile.o)
      rho::LogMessage::LogMessage(char const*, int, int, rho::LogSettings&, rho::LogCategory const&) in librholib.a(RhoLog.o)
      rho::LogMessage::addPrefix(char const*, int) in librholib.a(RhoLog.o)
      ...
  "rho::LogMessage::applyExcludeFilter(std::string&)", referenced from:
      rho::LogMessage& rho::LogMessage::operator+(char const* const&) in RhoCryptImpl.o
      rho::LogMessage& rho::LogMessage::operator+(char const (&) [19]) in RhoCryptImpl.o
      rho::LogMessage& rho::LogMessage::operator+(int const&) in RhoCryptImpl.o
      rho::LogMessage& rho::LogMessage::operator+(char const (&) [11]) in RhoCryptImpl.o
      rho::LogMessage& rho::LogMessage::operator+(char const (&) [48]) in RhoCryptImpl.o
      rho::LogMessage& rho::LogMessage::operator+(long const&) in RhoCryptImpl.o
      rho::LogMessage& rho::LogMessage::operator+(char const (&) [10]) in RhoCryptImpl.o
      ...
ld: symbol(s) not found for architecture armv7
clang: error: linker command failed with exit code 1 (use -v to see invocation)