On Tuesday 12 February 2013, Brad King wrote: > On 02/12/2013 01:47 PM, Alexander Neundorf wrote: ... > > 1) fail immediately in the targets file if a referenced target does not > > exist yet. If imported targets would be new, I would do this. But since > > they already exist for some time, there are most probably projects where > > the order of find_package() does not take the dependencies into account, > > so they build now, but would fail at cmake time then. Would that be > > acceptable ? > > This is the same as your previous proposal #1. I accepted it already but > require the policy for compatibility.
Yes, I know, but IMO with the compatibility here it does not make much sense. Even with updating cmake people will still run into link errors (and probably ignore the cmake warnings). > > 2) Collect the referenced imported targets and check later whether they > > all have been imported, and error out if not. > > I'm not completely sure when "later" is. > > First I thought at the end of the configure-step, but since imported > > targets do not have global scope, I think this has to be done per > > directory. So I could do this check in some way at the end of processing > > a CMakeLists.txt, i.e. before leaving a directory. > > This may be a better option with some C++-side support because it will not > require projects to change an already-working out-of-order import. It > would also potentially allow circular dependencies to work. One could > define a directory property that targets files can populate. It is simply > a list of target names that must exist by the time the directory is done: > > set_property(DIRECTORY APPEND PROPERTY REQUIRED_TARGETS ...) > > CMake can read this property at the end of a directory and produce an > error if it is not satisfied. A first try is now on stage in the ConfigFileTargetChecks4 branch. Tests and docs are still missing, error messages are not good yet, etc., but it should basically work. Please have a look at it, especially at the last commit (c80d330). Alex -- Powered by www.kitware.com Visit other Kitware open-source projects at http://www.kitware.com/opensource/opensource.html Please keep messages on-topic and check the CMake FAQ at: http://www.cmake.org/Wiki/CMake_FAQ Follow this link to subscribe/unsubscribe: http://public.kitware.com/cgi-bin/mailman/listinfo/cmake-developers
