Clion / Cmake can't find boost on linux - linux

Question

I recently changed to Linux Mint Debian Edition and cannot include boost to Clion using cmake. Yesterday I tried every option I could find, including on stackoverflow, but nothing has worked yet.
Boost has been installed using: sudo apt -y install libboost-filesystem-dev
This is a version I found in this thread: How to include external library (boost) into CLion C++ project with CMake?
which supposedly worked, but it didn't.
cmake_minimum_required(VERSION 3.22)
project(boost_project)
set(CMAKE_CXX_STANDARD 14)
find_package(Boost COMPONENTS system filesystem REQUIRED)
if(Boost_FOUND)
message(STATUS "Boost_INCLUDE_DIRS: ${Boost_INCLUDE_DIRS}")
message(STATUS "Boost_LIBRARIES: ${Boost_LIBRARIES}")
message(STATUS "Boost_VERSION: ${Boost_VERSION}")
include_directories(${Boost_INCLUDE_DIRS})
endif()
add_executable(boost_project main.cpp)
if(Boost_FOUND)
target_link_libraries(boost_project ${Boost_LIBRARIES})
endif()
The Cmake output message is:
CMake Error at /app/extra/clion/bin/cmake/linux/share/cmake-3.22/Modules/FindPackageHandleStandardArgs.cmake:230 (message):
Could NOT find Boost (missing: Boost_INCLUDE_DIR system filesystem)
I've gone through dozens of threads but so far nothing has worked. Has anyone suggestions of what's wrong?
EDIT:
So I've de-installed Clion and re-installed it with snap, since I read in another thread that it was an issue with installing Clion through the software center. Now I can include boost with no problem, but building it reveals the compiler still doesn't like using it.
#include <iostream>
#include "boost/asio.hpp"
boost::asio::io_service io_s;
int main() {
std::cout << "Hello, World!" << std::endl;
return 0;
}
: && /usr/bin/c++ -g CMakeFiles/BoostTest.dir/main.cpp.o -o BoostTest && :
/usr/bin/ld: CMakeFiles/BoostTest.dir/main.cpp.o: in function boost::asio::detail::posix_event::posix_event()': /usr/include/boost/asio/detail/impl/posix_event.ipp:42: undefined reference to pthread_condattr_setclock'
/usr/bin/ld: CMakeFiles/BoostTest.dir/main.cpp.o: in function boost::asio::detail::posix_thread::~posix_thread()': /usr/include/boost/asio/detail/impl/posix_thread.ipp:35: undefined reference to pthread_detach'
/usr/bin/ld: CMakeFiles/BoostTest.dir/main.cpp.o: in function boost::asio::detail::posix_thread::join()': /usr/include/boost/asio/detail/impl/posix_thread.ipp:42: undefined reference to pthread_join'
/usr/bin/ld: CMakeFiles/BoostTest.dir/main.cpp.o: in function boost::asio::detail::posix_thread::start_thread(boost::asio::detail::posix_thread::func_base*)': /usr/include/boost/asio/detail/impl/posix_thread.ipp:59: undefined reference to pthread_create'
/usr/bin/ld: CMakeFiles/BoostTest.dir/main.cpp.o: in function boost::asio::detail::posix_signal_blocker::posix_signal_blocker()': /usr/include/boost/asio/detail/posix_signal_blocker.hpp:43: undefined reference to pthread_sigmask'
/usr/bin/ld: CMakeFiles/BoostTest.dir/main.cpp.o: in function boost::asio::detail::posix_signal_blocker::~posix_signal_blocker()': /usr/include/boost/asio/detail/posix_signal_blocker.hpp:50: undefined reference to pthread_sigmask'
collect2: error: ld returned 1 exit status
ninja: build stopped: subcommand failed.

Answer 1

The solution to the first problem, cmake not finding boost, had nothing to do with cmake but Clion. Installing Clion with flatpak can apparently cause this error. To fix it I just needed to de-install Clion and re-install it with snap.
The second issue was cmake not finding several thread related includes. For that cmake needed
set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -pthread")
to be added. I found this solution in these threads:
linking errors for boost for visual studio linux project
Undefined reference to pthread_create in Linux
The complete and working cmake looks like this now:
cmake_minimum_required(VERSION 3.22)
project(boost_project)
message(STATUS "start running cmake...")
find_package(Boost COMPONENTS system)
if(Boost_FOUND)
message(STATUS "Boost_INCLUDE_DIRS: ${Boost_INCLUDE_DIRS}")
message(STATUS "Boost_LIBRARIES: ${Boost_LIBRARIES}")
message(STATUS "Boost_VERSION: ${Boost_VERSION}")
set(CMAKE_CXX_STANDARD 14)
add_executable(boost_project main.cpp)
include_directories(${Boost_INCLUDE_DIR})
link_directories(${Boost_LIBRARY_DIR})
set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -pthread")
endif()
target_link_libraries(boost_project ${Boost_LIBRARIES})