[SOLVED] CMake How to access headers and source files in a different folder

Issue

I have a code repository like image below. I'm trying to add a new standalone executable. The main.cpp and CMakeLists.txt files are located in folder4 and main.cpp requires code from folder3.

At the moment I'm using:

cmake_minimum_required(VERSION 3.10)

# set the project name
project(Standalone)

# add the executable
add_executable(StandaloneExe main.cpp)

Should I now use file( GLOB SRCS *.cpp *.h ) to retrieve the headers and source files from folder3?

I just want the simplest way of generating this executable.

Solution

Should I now use file( GLOB SRCS *.cpp *.h ) to retrieve the headers and source files from folder3?

No, you should never use GLOB to get sources. See my answer here for more detail: https://stackoverflow.com/a/65191951/2137996

I just want the simplest way of generating this executable.

Put your CMakeLists.txt in the root instead. Then just write:

cmake_minimum_required(VERSION 3.10)

# set the project name
project(Standalone)

# add the executable
add_executable(
  StandaloneExe
  folder2/folder4/main.cpp
  folder1/folder3/a.cpp
  folder1/folder3/b.cpp
)

# Might need this, maybe not, depending on your includes
target_include_directories(
  StandaloneExe
  PRIVATE 
    "${CMAKE_CURRENT_SOURCE_DIR}/folder1/folder3"
)

If you absolutely cannot move your lists file, then you can use absolute paths:

add_executable(
  StandaloneExe
  ${CMAKE_CURRENT_LIST_DIR}/../../folder2/folder4/main.cpp
  ${CMAKE_CURRENT_LIST_DIR}/../../folder1/folder3/a.cpp
  ${CMAKE_CURRENT_LIST_DIR}/../../folder1/folder3/b.cpp
)

Answered By - Alex Reinking