Dear all:
    I'm using QNX 7 on ubuntu 18.04 OS. Using include path qnx700/target/qnx7/usr/include/c++/5.4.0 to complie Google's 
Gtest, compile success. But using include path qnx700/target/qnx7/usr/include/c++/v1, encountered the follow errors:
./libgtest_main.a(gtest-all.o): In function `testing::internal::Random::Generate(unsigned int)':
googletest/make/../src/gtest.cc:348: undefined reference to `std::__1::basic_ostream<char, std::__1::char_traits<char> >
::operator<<(unsigned int)'
googletest/make/../src/gtest.cc:349: undefined reference to `std::__1::basic_ostream<char, std::__1::char_traits<char> >
::operator<<(unsigned int)'

What is the diffeerence between of 5.4.0 and  v1?
What path should be included for C++ project?