c++ - cmake add_custom_command failure, target gets deleted -

i building test executable using cmake. during build process, run executable, returns whether tests pass or not. if not, build fail. however, when use add_custom_command(... post_build ... ), , use makefile generator, test executable deleted (explain in question: why gnu make delete file).

is there way have cmake treat executable .precious, or otherwise change cmakelists.txt such executable doesn't deleted if tests fail?

for reference, cmakelist.txt looks following (simplified actual):

add_executable(unittest unittest.cpp) add_custom_command(target unittest post_build command $<target_file:unittest>) 

the solution alluding use add_custom_target instead of add_custom_command. while not delete executable if test fails , build process whole fails if rununittest fails, target not built result of building unittest target specifically.

add_executable(unittest unittest.cpp) add_custom_target(rununittest unittest command $<target_file:unittest> depends unittest)