cmake: add_custom_command with dependency in a different directory -

yet add_custom_command question:

i have project in output of 1 custom command used input another, in different directory. example:

directory lib/cmakelists.txt contains:

add_custom_command(     output libfoo.xx     command <command build libfoo.xx> ) add_custom_target(libfoo depends libfoo.xx) 

directory test/cmakelists.txt contains:

add_custom_command(output test.yy    command <command build test.yy>    depends "${project_binary_dir}/lib/libfoo.xx" ) 

so need make sure libfoo build before test.yy. docs depends clause of add_custom_command() can have file-level dependencies. let's try , see happens:

no rule make target 'lib/libfoo.xx', needed 'test/test.yy'.  stop. 

if on other hand, attempt create target-level dependency saying depends libfoo, error changes to:

no rule make target 'libfoo', needed 'test/test.yy'.  stop. 

so seems neither file-level or target-level dependencies work here. there way have output 1 custom command input custom command, in different directory?

you try in test/cmaklists.txt add

add_custom_target(test depends test.yy) 

and add

add_dependencies(test libfoo) 

in top-level cmakelists.txt.

disclaimer: didn't test , i'm cmake beginner. tell if works!