Threads: Use IMPORTED target

Author: ferdnyc

src/CMakeLists.txt

@@ -273,6 +273,13 @@ set_target_properties(openshot
 		INSTALL_NAME_DIR "${CMAKE_INSTALL_PREFIX}/lib"
 		)
 
+################### Threads ####################
+# Threading library -- uses IMPORTED target Threads::Threads (since CMake 3.1)
+set(CMAKE_THREAD_PREFER_PTHREAD TRUE)
+set(THREADS_PREFER_PTHREAD_FLAG TRUE)
+find_package(Threads REQUIRED)
+target_link_libraries(openshot PUBLIC Threads::Threads)
+
 ################### OPENMP #####################
 # Check for OpenMP (used for multi-core processing)
 
@@ -284,7 +291,6 @@ if(NOT TARGET OpenMP::OpenMP_CXX)
     add_library(OpenMP_TARGET INTERFACE)
     add_library(OpenMP::OpenMP_CXX ALIAS OpenMP_TARGET)
     target_compile_options(OpenMP_TARGET INTERFACE ${OpenMP_CXX_FLAGS})
-    find_package(Threads REQUIRED)
     target_link_libraries(OpenMP_TARGET INTERFACE Threads::Threads)
     target_link_libraries(OpenMP_TARGET INTERFACE ${OpenMP_CXX_FLAGS})
 endif()