| # Add a target that requires step1 to run first but enforces |
| # it only by target-level ordering dependency. |
| add_custom_command( |
| OUTPUT step2.txt |
| COMMAND ${CMAKE_COMMAND} -E copy step1.txt step2.txt |
| ) |
| add_custom_target(step2 DEPENDS step2.txt) |
| add_dependencies(step2 step1) |
| |
| # Add a target that requires step1 and step2 to work, |
| # only depends on step1 transitively through step2, but |
| # also gets a copy of step2's custom command. |
| # The Ninja generator in particular must be careful with |
| # this case because it needs to compute the proper set of |
| # target ordering dependencies for the step2 custom command |
| # even though it appears in both the step2 and step3 |
| # targets due to dependency propagation. |
| add_custom_command( |
| OUTPUT step3.txt |
| COMMAND ${CMAKE_COMMAND} -E copy step1.txt step3-1.txt |
| COMMAND ${CMAKE_COMMAND} -E copy step2.txt step3.txt |
| DEPENDS ${CMAKE_CURRENT_BINARY_DIR}/step2.txt |
| ) |
| add_custom_target(step3 ALL DEPENDS step3.txt) |
| add_dependencies(step3 step2) |
| |
| # We want this target to always run first. Add it last so |
| # that serial builds require dependencies to order it first. |
| add_custom_target(step1 |
| COMMAND ${CMAKE_COMMAND} -E touch step1.txt |
| ) |