CMake error: 'target is not built by this project'

Question

My CMakeLists.txt file is:

cmake_minimum_required(VERSION 3.7)
project(OpenCV_Basics)

set(CMAKE_CXX_STANDARD 11)

set(SOURCE_FILES main.cpp)

find_package(OpenCV REQUIRED)
include_directories(${OpenCV_INCLUDE_LIBS})
target_link_libraries(OpenCV_Basics )

add_executable(OpenCV_Basics ${SOURCE_FILES})

When I tried to compile the main.cpp, I got stucked.

CMake Error at CMakeLists.txt:10 (target_link_libraries):
  Cannot specify link libraries for target "OpenCV_Basics" which is not 
built
  by this project.

What's wrong?

I am working in Clion on Mac.

Answer 1

add_executable defines a target, but on your code you define a target after trying to compile it.

just change the position of those two lines:

• first define the target

• link the library.

like this

add_executable(OpenCV_Basics ${SOURCE_FILES})
target_link_libraries(OpenCV_Basics )

Answer 2

When any CMake command accepts target argument, it expects given target to be already created.

Correct usage:

# Create target 'OpenCV_Basics' 
add_executable(OpenCV_Basics ${SOURCE_FILES})
# Pass the target to other commands
target_link_libraries(OpenCV_Basics ${OpenCV_LIBRARIES})