NtCore Linker error for cmake (please help) now with :Thread:

#1

Hello Robotics Users, Today our programming team ran it to ntcore c++ linker errors for our vision processor rpi4. Could i please have help with this.

here are our errors

[50%] Linking CXX executable Robotkinect

/bin/ld: /usr/local/wpilib/lib/libntcore.so: undefined reference to `std::thread::_State::~_State()@GLIBCXX_3.4.22’

/bin/ld: /usr/local/wpilib/lib/libntcore.so: undefined reference to vtable for std::thread::_State@GLIBCXX_3.4.22' /bin/ld: /usr/local/wpilib/lib/libntcore.so: undefined reference to typeinfo for std::thread::_State@GLIBCXX_3.4.22’

/bin/ld: /usr/local/wpilib/lib/libntcore.so: undefined reference to `std::thread::_M_start_thread(std::unique_ptr<std::thread::_State,

std::default_deletestd::thread::_State >, void (*)())@GLIBCXX_3.4.22’
collect2: error: ld returned 1 exit status

make[2]: *** [CMakeFiles/Robotkinect.dir/build.make:86: Robotkinect] Error 1
make[1]: *** [CMakeFiles/Makefile2:76: CMakeFiles/Robotkinect.dir/all] Error 2

make: *** [Makefile:84: all] Error 2

#2

You can use three backticks ``` to quote your code/transcript so it doesn’t change into emoji.

How did you build/install ntcore? What does your project’s cmake file look like? Those errors look like you’re either not linking using the g++ command, or not linking to the right underlying libstdc++ and pthread libraries. The cmake file can be as simple as the one I put into this post: Ntcore installation error (Jetson)