How to link same set of libraries to multiple targets/executables in cmake? - cmake

Question

I have multiple executable/target files in my project structure, and they all use the same libraries. Is there a way to make this more compact? Perhaps something like a for-loop?
set(ALL_LIBS lib1 lib2 lib3) # etc.
add_executable(program1 program1.cpp)
target_link_libraries(program1 PRIVATE ${ALL_LIBS})
add_executable(program2 program2.cpp)
target_link_libraries(program2 PRIVATE ${ALL_LIBS})
add_executable(program3 program3.cpp)
target_link_libraries(program3 PRIVATE ${ALL_LIBS})
add_executable(program4 program4.cpp)
target_link_libraries(program4 PRIVATE ${ALL_LIBS})
I'm looking for a solution that achieves something similar or cleaner than this:
add_executable(program1 program1.cpp)
add_executable(program2 program2.cpp)
add_executable(program3 program3.cpp)
add_executable(program4 program4.cpp)
# somehow get list of target names
foreach(${TARGETS})
# link libraries to each target
target_link_libraries(${TARGET_NAME} PRIVATE ${ALL_LIBS})
endforeach()

Answer 1

You may define your own macro or function which defines an executable like normal add_executable but also links the executable with the common libraries.
set(ALL_LIBS lib1 lib2 lib3) # etc.
# A wrapper around add_executable which links all created executables with libraries
function(add_executable_common name)
# Forward all parameters to add_executable
add_executable(${ARGV})
# Perform additional actions
target_link_libraries(${name} PRIVATE ${ALL_LIBS})
endfunction()
# Created function can be used in the very same manner as add_executable.
add_executable_common(program1 program1.cpp)
add_executable_common(program2 program2.cpp)
add_executable_common(program3 program3.cpp)
add_executable_common(program4 program4.cpp)
CMake variables ARGV and ARGN provide a perfect way to forward parameters of one function/macro to another.
This allows to easily create wrappers to existed functions without needs to parse all parameters needed for the wrapped function.
E.g. while the function add_executable_common, defined above, doesn't parse parameters except the first one, it still can be used for define a STATIC or SHARED library and can be used for define a library with several sources:
add_executable_common(program5 SHARED program5.cpp additional_algos.cpp)

Answer 2

I found an okay solution to reduce line count. I just created a function to accept target name and file paths.
function(add_program_target TARGET_NAME)
add_executable(${TARGET_NAME} ${ARGN})
target_link_libraries(${TARGET_NAME} PRIVATE ${ALL_LIBS})
endfunction()
Then I just add targets like this:
add_program_target(program1 program1.cpp helper.cpp)
add_program_target(program2 program2.cpp)
add_program_target(program2 program3.cpp)
add_program_target(program2 program4.cpp)
# etc.