build: align minimum build dependencies with ndn-cxx

 * Recommend gcc >= 7.4.0
 * Require clang >= 4.0, or Xcode >= 9.0 on macOS
 * Silence an ABI-related diagnostic message from gcc on armv7
 * Update Travis CI job matrix

Refs: #5087, #5106
Change-Id: I71aef00147a7ad93b537904bb309745fed77f509
diff --git a/tests/boost-multi-log-formatter.hpp b/tests/boost-multi-log-formatter.hpp
deleted file mode 100644
index ae37416..0000000
--- a/tests/boost-multi-log-formatter.hpp
+++ /dev/null
@@ -1,214 +0,0 @@
-/* -*- Mode:C++; c-file-style:"gnu"; indent-tabs-mode:nil; -*- */
-/**
- * Copyright (c) 2015 Regents of the University of California.
- *
- * Based on work by Martin Ba (http://stackoverflow.com/a/26718189)
- *
- * This file is distributed under the Boost Software License, Version 1.0.
- * (See http://www.boost.org/LICENSE_1_0.txt)
- */
-
-#ifndef NDN_TESTS_BOOST_MULTI_LOG_FORMATTER_HPP
-#define NDN_TESTS_BOOST_MULTI_LOG_FORMATTER_HPP
-
-#include <boost/version.hpp>
-
-#if BOOST_VERSION >= 105900
-#include <boost/test/unit_test_parameters.hpp>
-#else
-#include <boost/test/detail/unit_test_parameters.hpp>
-#endif // BOOST_VERSION >= 105900
-
-#include <boost/test/unit_test_log_formatter.hpp>
-#include <boost/test/output/compiler_log_formatter.hpp>
-#include <boost/test/output/xml_log_formatter.hpp>
-
-namespace boost {
-namespace unit_test {
-namespace output {
-
-/**
- * @brief Log formatter for Boost.Test that outputs the logging to multiple formatters
- *
- * The log formatter is designed to output to one or multiple formatters at the same time.  For
- * example, one HRF formatter can output to the standard output, while XML formatter output to
- * the file.
- *
- * Usage:
- *
- *     // Call in init_unit_test_suite: (this will override the --log_format parameter)
- *     auto formatter = new boost::unit_test::output::multi_log_formatter; // same as already configured logger
- *
- *     // Prepare and add additional logger(s)
- *     formatter.add(std::make_shared<boost::unit_test::output::xml_log_formatter>(),
- *                   std::make_shared<std::ofstream>("out.xml"));
- *
- *      boost::unit_test::unit_test_log.set_formatter(formatter);
- *
- * @note Calling `boost::unit_test::unit_test_log.set_stream(...)` will change the stream for
- *       the original logger.
- */
-class multi_log_formatter : public unit_test_log_formatter
-{
-public:
-  /**
-   * @brief Create instance of the logger, based on the configured logger instance
-   */
-  multi_log_formatter()
-  {
-    auto format =
-#if BOOST_VERSION > 105900
-      runtime_config::get<output_format>(runtime_config::LOG_FORMAT);
-#else
-      runtime_config::log_format();
-#endif // BOOST_VERSION > 105900
-
-    switch (format) {
-      default:
-#if BOOST_VERSION >= 105900
-      case OF_CLF:
-#else
-      case CLF:
-#endif // BOOST_VERSION >= 105900
-        m_loggers.push_back({std::make_shared<compiler_log_formatter>(), nullptr});
-        break;
-#if BOOST_VERSION >= 105900
-      case OF_XML:
-#else
-      case XML:
-#endif // BOOST_VERSION >= 105900
-        m_loggers.push_back({std::make_shared<xml_log_formatter>(), nullptr});
-        break;
-    }
-  }
-
-  void
-  add(std::shared_ptr<unit_test_log_formatter> formatter, std::shared_ptr<std::ostream> os)
-  {
-    m_loggers.push_back({formatter, os});
-  }
-
-  // Formatter interface
-  void
-  log_start(std::ostream& os, counter_t test_cases_amount)
-  {
-    for (auto& l : m_loggers)
-      l.logger->log_start(l.os == nullptr ? os : *l.os, test_cases_amount);
-  }
-
-  void
-  log_finish(std::ostream& os)
-  {
-    for (auto& l : m_loggers)
-      l.logger->log_finish(l.os == nullptr ? os : *l.os);
-  }
-
-  void
-  log_build_info(std::ostream& os)
-  {
-    for (auto& l : m_loggers)
-      l.logger->log_build_info(l.os == nullptr ? os : *l.os);
-  }
-
-  void
-  test_unit_start(std::ostream& os, const test_unit& tu)
-  {
-    for (auto& l : m_loggers)
-      l.logger->test_unit_start(l.os == nullptr ? os : *l.os, tu);
-  }
-
-  void
-  test_unit_finish(std::ostream& os, const test_unit& tu, unsigned long elapsed)
-  {
-    for (auto& l : m_loggers)
-      l.logger->test_unit_finish(l.os == nullptr ? os : *l.os, tu, elapsed);
-  }
-
-  void
-  test_unit_skipped(std::ostream& os, const test_unit& tu)
-  {
-    for (auto& l : m_loggers)
-      l.logger->test_unit_skipped(l.os == nullptr ? os : *l.os, tu);
-  }
-
-#if BOOST_VERSION >= 105900
-  void
-  log_exception_start(std::ostream& os, const log_checkpoint_data& lcd, const execution_exception& ex)
-  {
-    for (auto& l : m_loggers)
-      l.logger->log_exception_start(l.os == nullptr ? os : *l.os, lcd, ex);
-  }
-
-  void
-  log_exception_finish(std::ostream& os)
-  {
-    for (auto& l : m_loggers)
-      l.logger->log_exception_finish(l.os == nullptr ? os : *l.os);
-  }
-#else
-  void
-  log_exception(std::ostream& os, const log_checkpoint_data& lcd, const execution_exception& ex)
-  {
-    for (auto& l : m_loggers)
-      l.logger->log_exception(l.os == nullptr ? os : *l.os, lcd, ex);
-  }
-#endif // BOOST_VERSION >= 105900
-
-  void
-  log_entry_start(std::ostream& os, const log_entry_data& entry_data, log_entry_types let)
-  {
-    for (auto& l : m_loggers)
-      l.logger->log_entry_start(l.os == nullptr ? os : *l.os, entry_data, let);
-  }
-
-  void
-  log_entry_value(std::ostream& os, const_string value)
-  {
-    for (auto& l : m_loggers)
-      l.logger->log_entry_value(l.os == nullptr ? os : *l.os, value);
-  }
-
-  void
-  log_entry_finish(std::ostream& os)
-  {
-    for (auto& l : m_loggers)
-      l.logger->log_entry_finish(l.os == nullptr ? os : *l.os);
-  }
-
-#if BOOST_VERSION >= 105900
-  void
-  entry_context_start(std::ostream& os, log_level level)
-  {
-    for (auto& l : m_loggers)
-      l.logger->entry_context_start(l.os == nullptr ? os : *l.os, level);
-  }
-
-  void
-  log_entry_context(std::ostream& os, const_string value)
-  {
-    for (auto& l : m_loggers)
-      l.logger->log_entry_context(l.os == nullptr ? os : *l.os, value);
-  }
-
-  void
-  entry_context_finish(std::ostream& os)
-  {
-    for (auto& l : m_loggers)
-      l.logger->entry_context_finish(l.os == nullptr ? os : *l.os);
-  }
-#endif // BOOST_VERSION >= 105900
-
-private:
-  struct LoggerInfo
-  {
-    std::shared_ptr<unit_test_log_formatter> logger;
-    std::shared_ptr<std::ostream> os;
-  };
-  std::vector<LoggerInfo> m_loggers;
-};
-
-} // namespace output
-} // namespace unit_test
-} // namespace boost
-
-#endif // NDN_TESTS_BOOST_MULTI_LOG_FORMATTER_HPP
diff --git a/tests/main.cpp b/tests/main.cpp
index 70d0433..d6119af 100644
--- a/tests/main.cpp
+++ b/tests/main.cpp
@@ -1,115 +1,21 @@
-/* -*- Mode:C++; c-file-style:"gnu"; indent-tabs-mode:nil; -*- */
+/* -*- Mode: C++; c-file-style: "gnu"; indent-tabs-mode:nil -*- */
 /*
- * Copyright (c) 2014-2019,  Regents of the University of California,
- *                           Arizona Board of Regents,
- *                           Colorado State University,
- *                           University Pierre & Marie Curie, Sorbonne University,
- *                           Washington University in St. Louis,
- *                           Beijing Institute of Technology,
- *                           The University of Memphis.
+ * Copyright (c) 2012-2020 University of California, Los Angeles
  *
  * This file is part of ChronoSync, synchronization library for distributed realtime
- * applications for NDN, originally developed as part of NFD (Named Data Networking
- * Forwarding Daemon).  See AUTHORS.md for complete list of NFD authors and contributors.
+ * applications for NDN.
  *
- * NFD is free software: you can redistribute it and/or modify it under the terms
- * of the GNU General Public License as published by the Free Software Foundation,
- * either version 3 of the License, or (at your option) any later version.
+ * ChronoSync is free software: you can redistribute it and/or modify it under the terms
+ * of the GNU General Public License as published by the Free Software Foundation, either
+ * version 3 of the License, or (at your option) any later version.
  *
- * NFD is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY;
+ * ChronoSync is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY;
  * without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR
  * PURPOSE.  See the GNU General Public License for more details.
  *
  * You should have received a copy of the GNU General Public License along with
- * NFD, e.g., in COPYING.md file.  If not, see <http://www.gnu.org/licenses/>.
+ * ChronoSync, e.g., in COPYING.md file.  If not, see <http://www.gnu.org/licenses/>.
  */
 
 #define BOOST_TEST_MODULE ChronoSync
-
-#include <boost/version.hpp>
-
-#if BOOST_VERSION >= 106200
-// Boost.Test v3.3 (Boost 1.62) natively supports multi-logger output
 #include "tests/boost-test.hpp"
-#else
-#define BOOST_TEST_ALTERNATIVE_INIT_API
-#define BOOST_TEST_NO_MAIN
-#include "tests/boost-test.hpp"
-#include "tests/boost-multi-log-formatter.hpp"
-
-#include <boost/program_options/options_description.hpp>
-#include <boost/program_options/variables_map.hpp>
-#include <boost/program_options/parsers.hpp>
-
-#include <fstream>
-#include <iostream>
-
-static bool
-init_tests()
-{
-  init_unit_test();
-
-  namespace po = boost::program_options;
-  namespace ut = boost::unit_test;
-
-  po::options_description extraOptions;
-  std::string logger;
-  std::string outputFile = "-";
-  extraOptions.add_options()
-    ("log_format2", po::value<std::string>(&logger), "Type of second log formatter: HRF or XML")
-    ("log_sink2", po::value<std::string>(&outputFile)->default_value(outputFile), "Second log sink, - for stdout")
-    ;
-  po::variables_map vm;
-  try {
-    po::store(po::command_line_parser(ut::framework::master_test_suite().argc,
-                                      ut::framework::master_test_suite().argv)
-                .options(extraOptions)
-                .run(),
-              vm);
-    po::notify(vm);
-  }
-  catch (const std::exception& e) {
-    std::cerr << "ERROR: " << e.what() << "\n"
-              << extraOptions << std::endl;
-    return false;
-  }
-
-  if (vm.count("log_format2") == 0) {
-    // second logger is not configured
-    return true;
-  }
-
-  std::shared_ptr<ut::unit_test_log_formatter> formatter;
-  if (logger == "XML") {
-    formatter = std::make_shared<ut::output::xml_log_formatter>();
-  }
-  else if (logger == "HRF") {
-    formatter = std::make_shared<ut::output::compiler_log_formatter>();
-  }
-  else {
-    std::cerr << "ERROR: only HRF or XML log formatter can be specified" << std::endl;
-    return false;
-  }
-
-  std::shared_ptr<std::ostream> output;
-  if (outputFile == "-") {
-    output = std::shared_ptr<std::ostream>(&std::cout, std::bind([]{}));
-  }
-  else {
-    output = std::make_shared<std::ofstream>(outputFile.c_str());
-  }
-
-  auto multiFormatter = new ut::output::multi_log_formatter;
-  multiFormatter->add(formatter, output);
-  ut::unit_test_log.set_formatter(multiFormatter);
-
-  return true;
-}
-
-int
-main(int argc, char* argv[])
-{
-  return ::boost::unit_test::unit_test_main(&init_tests, argc, argv);
-}
-
-#endif // BOOST_VERSION >= 106200