Warnings C4244, C4305, C4722, ... when compiling with MS Visual Studio 2017 15.9.12

googlebenchmark\src\benchmark_runner.cc(267): warning C4244: 'initializing': conversion from 'double' to 'benchmark::IterationCount', possible loss of data googlebenchmark\src\benchmark_runner.cc(267): warning C4244: 'initializing': conversion from 'double' to 'const benchmark::IterationCount', possible loss of data d:\thirdparty\trunk\googlebenchmark\test\statistics_gtest.cc(25): warning C4305: 'argument': truncation from 'double' to 'RawType' googlebenchmark\test\statistics_gtest.cc(24): warning C4244: 'argument': conversion from 'double' to 'RawType', possible loss of data googlebenchmark\src\benchmark_register.h(25): warning C4244: '=': conversion from 'int' to 'T', possible loss of data googlebenchmark\third_party\googletest\src\googlemock\include\gmock\gmock-matchers.h(156): warning C4244: 'argument': conversion from 'const M' to 'const Element', possible loss of data googlebenchmark\src\check.h(41): warning C4722: 'benchmark::internal::CheckHandler::~CheckHandler': destructor never returns, potential memory leak googlebenchmark\src\benchmark_runner.cc(267): warning C4244: 'initializing': conversion from 'double' to 'benchmark::IterationCount', possible loss of data googlebenchmark\src\benchmark_runner.cc(267): warning C4244: 'initializing': conversion from 'double' to 'const benchmark::IterationCount', possible loss of data googlebenchmark\src\check.h(41): warning C4722: 'benchmark::internal::CheckHandler::~CheckHandler': destructor never returns, potential memory leak googlebenchmark\test\statistics_gtest.cc(25): warning C4305: 'argument': truncation from 'double' to 'RawType' googlebenchmark\test\statistics_gtest.cc(24): warning C4244: 'argument': conversion from 'double' to 'RawType', possible loss of data googlebenchmark\src\check.h(41): warning C4722: 'benchmark::internal::CheckHandler::~CheckHandler': destructor never returns, potential memory leak googlebenchmark\src\check.h(41): warning C4722: 'benchmark::internal::CheckHandler::~CheckHandler': destructor never returns, potential memory leak googlebenchmark\src\check.h(41): warning C4722: 'benchmark::internal::CheckHandler::~CheckHandler': destructor never returns, potential memory leak googlebenchmark\src\benchmark_register.h(25): warning C4244: '=': conversion from 'int' to 'T', possible loss of data googlebenchmark\third_party\googletest\src\googlemock\include\gmock\gmock-matchers.h(156): warning C4244: 'argument': conversion from 'const M' to 'const Element', possible loss of data googlebenchmark\src\check.h(41): warning C4722: 'benchmark::internal::CheckHandler::~CheckHandler': destructor never returns, potential memory leak googlebenchmark\src\check.h(41): warning C4722: 'benchmark::internal::CheckHandler::~CheckHandler': destructor never returns, potential memory leak