I am trying to use an external library (libmylib.so) in my package ROS. My problem is that this library required pthread to compile.

I have already use pthread in my work. So, I add pthread rt in the targetlinklibraries :

target_link_libraries(mypackage 
    ${catkin_LIBRARIES} 
    ${mylib} 
    pthread rt)

Without using CMake it works fine but using Cmake I foud two errors:

${PATH_TO_MY_LIB}/libmylib.so: undefined reference to 'pthread_create' 
${PATH_TO_MY_LIB}/libmylib.so: undefined reference to 'pthread_cancel'

I founded the same error with these others tests :

Test 1:

add_definietions("-std=c++11 -Wall -g -lpthread")
list(APPEND CMAKE_CXX_FLAGS "-lpthread"

Test 2:

find(package(Threads REQUIRED)
target_link_libraries( mypackage 
    ${catkin_LIBRARIES} 
    ${mylib} 
    ${CMAKE_THREAD_LIBS_INIT} )

Test 3:

set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -std=c++11 -pthread")

Test 4:

set(CMAKE_LINKER_FLAGS "-pthread" CACHE STRING "Linker Flags" FORCE)
set(CMAKE_SHARED_LINKER_FLAGS "${CMAKE_LINKER_FLAGS}" CACHE STRING "" FORCE)
set(CMAKE_MODULE_LINKER_FLAGS "${CMAKE_LINKER_FLAGS}" CACHE STRING "" FORCE)
set(CMAKE_EXE_LINKER_FLAGS    "${CMAKE_LINKER_FLAGS}" CACHE STRING "" FORCE)

Test 5:

set_target_properties(mypackage PROPERTIES COMPILE_FLAGS -pthread LINK_FLAGS -pthread)

I am open to any suggestion ! Thank you