gcc - How do I force cmake to include "-pthread" option during compilation?

Question

I know there is something like find_package(Threads) but it doesn't seem to make a difference (at least by itself). For now I'm using SET(CMAKE_C_FLAGS ${CMAKE_C_FLAGS} "-pthread"), but it doesn't look like a correct solution to me.

Answer 1

The Threads module in the latest versions (>= 3.1) of CMake generates the Threads::Threads imported target. Linking your target against Threads::Threads adds all the necessary compilation and linking flags. It can be done like this:

set(CMAKE_THREAD_PREFER_PTHREAD TRUE)
set(THREADS_PREFER_PTHREAD_FLAG TRUE)
find_package(Threads REQUIRED)

add_executable(test test.cpp)
target_link_libraries(test Threads::Threads)

Use of the imported target is highly recommended for new code, according to the CMake docs