The dependency between libraries and libraries+executable could be managed via target_link_libraries. So if some library fails build - all dependent targets will not build.
I have another task: there are exist the library target, the executable test target (that provide test for library) and the main executable target with main logic.
I need that main executable target should be build only if build of the executable test target is not fails.
In other word I need set up dependency between two executables.
How I could achieve it? Could somebody provide an example?
Testing is a different stage in the CMake/Ctest/CPack suite, so you’re unlikely to find a way to conditionally compile/link an executable based on test results.
You can use add_dependencies to ensure that the test executable builds first, but that’s not the same as only producing a build product of the test runs successfully.
I recommend running your build followed by the test. Based on the return code of the test, you can choose whether or not to package the final product.
Related
I'm using CMake for a project where I want to bundle Clang. I use ExternalProject_Add to build clang from source. However, since Clang and LLVM is huge, a make with nothing changed takes 45 seconds.
Is there a way to make CMake just build the ExternalProject once, and then not even check if anything has changed on subsequent runs if it has already been built successfully?
The best way to use ExternalProject_Add() is to structure your project as a superbuild. This means that your top-level project (the "superbuild") does not build any actual code and instead consists only of ExternalProject_Add calls. Your "real" project is added as one of these "external" projects. This allows you to set up the superbuild with all dependencies, ordering, etc.
The workflow is then as follows:
Generate the superbuild project.
Build the superbuild project. This will build and install all dependencies, and also generate (and build) your real project.
Switch to the buildsystem generated for your real project and start doing further development using that. Your dependencies are already correctly set up and installed by the build of the superbuild project in the previous step, and will never be checked for out-of-dateness by the build.
If you ever need to change the setup of your dependencies, do it and build the superbuild again.
In my CMake project I have several targets which simply run a certain set of unit tests (for example, runTestsForA, runTestsForB and runTestsForC).
I also have a target, tests, that depends on all of these unit test targets, so I can run them with a single command.
I'm using CLion is my IDE, which tries to use parallel make builds by default (which I want and am also doing on the Continuous Integration server).
However, it looks like the tests are running in parallel too now and some tests are not made for this (they use a local loopback to do some magic with sockets), which causes them to fail.. sometimes.
That is why I would like to force serial execution for some/all of the dependencies of my tests target.
Unfortunately the CMake documentation did not help me, when I was searching information on how to do this.
Which brings me to my questions: is this at all possible and how can it be done if it is?
Instead of manual tests target declaration you can use CTest tool. Use add_test command to create test targets, then CMake will automatically create tests target that will run all tests:
enable_testing()
add_test(NAME TestsForA COMMAND <command>)
add_test(NAME TestsForB COMMAND <command>)
set_tests_properties(TestsForA TestsForB PROPERTIES RUN_SERIAL TRUE)
After that you can run make tests or ctest -j8 . in your build tree. The tests will be serialized.
More information can be found at:
http://www.cmake.org/cmake/help/v3.2/command/add_test.html
http://www.cmake.org/cmake/help/v3.2/command/enable_testing.html
http://www.cmake.org/cmake/help/v3.2/command/set_tests_properties.html
http://www.cmake.org/cmake/help/v3.2/manual/cmake-properties.7.html#properties-on-tests
http://www.cmake.org/cmake/help/v3.2/manual/ctest.1.html
Perhaps it's not the best solution for controlling test execution, but, generally I believe you can use the CMake JOB_POOLS feature to restrict the amount of parallelism for some of the CMake targets in a project.
First you declare named pool(s) and the number of parallel jobs each pool supports:
set_property(GLOBAL PROPERTY JOB_POOLS two_jobs=2 ten_jobs=10)
You can then assign targets to those pools:
set_property(TARGET myexe PROPERTY JOB_POOL_COMPILE ten_jobs)
How to only build a static library with clion without having an executable?
How does the CMakeLists.txt look like? (without add_executable)
Update: If I don't add executable to Clion, I have an
error, that an executable is required.
Here my CMakeLists.txt.
This is an old question. But I'll add the answer to your question as a help for other people. You need to replace your add_executable with add_library
add_library(target_name source_files)
Short answer: compile the library target and run any custom command as a placeholder to avoid the warning.
Long answer:
CLion lets you either build the whole project and run executables/configurations.
When running executables, you can choose a target to compile and the executable to run after compiling the target. For executable targets, they are usually the same thing. You compile the executable target and then run it.
It seems like this is not really designed for libraries, but there is a workaround. You usually set the target to be the library and the executable to be any executable that depends on this library. However, this is usually not very useful because if you wanted to run this executable you could just set this executable to be the target and the library would be built anyway.
So people probably want to just build the library (to check if everything is OK, etc) without compiling or running any extra executable targets. In this case, the workaround is to choose a custom executable to run after building the library, and the error message is gone.
You have nothing useful you need to run after building the library, just choose any cheap command as a placeholder. Something like "pwd" or "ls".
I'm considering to use CMake for projects targeting a microcontroller. I found out how to create a toolchain file and invoke cmake -DCMAKE_TOOLCHAIN_FILE=Path/To/Toolchain.cmake to make CMake do cross-compiling.
However most projects that I work on have also code that must be compiled for the host platform. These are often unit tests or other test tools, which share most part of their code with the binary that will run on the microcontroller. A rare case might be a project that even has two processors having a different instruction architectures, thus needing a host compiler and two different cross compilers.
I'd like to have one build that rules them all. Is it possible to have a construction that I only need to call cmake /path/to/source && make, or is the only solution having multiple 'root' CMakeList.txt files, each for every target?
Each cmake run will target one specific generator and thus one platform.
What you want can be achieved by having one hierarchy of CMakeLists files for each platform. You need to get to a point where doing a succession of cmake .. && make calls will build the whole project.
Then write a master CMakeLists that executes all of those separate build steps for you, e.g. through ExternalProject_Add or by using custom commands. Depending on the structure of your project it might make sense to have only the tools required for building being processed this way and add the sources for the actual project directly to the master CMakeLists instead.
I have defined a custom target in cmake. I now want to ensure that this target is only build when the cmake target test was executed. How can I achieve this.
Lets say that I have a target make coverage which should depend on the target make test to be called before, or call make test before executing.
How can I define this behavior in cmake?
Here my code that did not work as expected. I want to achive that make coverage depend that make test has to be called before.
ADD_CUSTOM_TARGET(
coverage COMMAND /bin/bash ${LIBPIPE_BINARY_DIR}/cmake/scripts/coverage.sh
DEPENDS test
)
You cannot add a "DEPENDS test" clause. The pre-defined/built-in targets in CMake (all, install, package, test, clean) are not available as actual targets in a CMakeLists.txt file. So you cannot express a dependency on a built-in target.
There is an outstanding feature request in the CMake bug tracker for this feature, but it is not yet implemented. See http://public.kitware.com/Bug/view.php?id=8438
However, you could change your command for your custom target, though, such that it calls "make test" first, and then runs your coverage command.
The CMake FAQ states that the add_custom_command/add_custom_target commands, which define custom targets, have a DEPENDS parameter.
Edit
This will not work for built-in target test because of following feature request.
But you always can create custom target check or whatever as suggested in CMake FAQ