CMake: execute a macro/function as the command of add_custom_command

cmake add-custom-command
Nicola Mori picture Nicola Mori · Jan 14, 2015 · Viewed 10.2k times · Source

I'm using an external library which provides a CMake function for automatic code generation, to be used in my CMakeLists. The problem is that whenever I modify a CMakeLists then the function is run again, triggering the recompilation of the newly generated but unchanged sources. I'd need something like add_custom_command with the possibility to specify the CMake function as COMMAND instead of an executable, so that the function is run only if the automatically generated files are not already present. Is this feasible? If not, does it exist another way to obtain the same result? Thanks.

Answer

cromod picture cromod · Apr 12, 2016

Take a look to this SO post.

You can call your function in a separate CMake script, call this script with add_custom_target and cmake -P then add a dependency to your binary :

add_custom_target(run_script COMMAND ${CMAKE_COMMAND} -P separate_script.cmake)
add_executable(your_binary ...)
# or add_library(your_binary ...)
add_dependencies(your_binary run_script)

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