On 11/05/2010 02:09 AM, Alan W. Irwin wrote: > On 2010-11-04 16:29-0700 SK wrote: > >> On Sat, Oct 30, 2010 at 8:31 AM, Alan W. Irwin >> <ir...@beluga.phys.uvic.ca> wrote: >>> On 2010-10-29 20:50-0700 mina adel wrote: >>> >>>> >>>> Hi All >>>> >>>> I have an open source code that I use in my project. This open source code >>>> already has Makefile coded for it. >>>> >>>> I want to use cmake so that before it compile my project it first call the >>>> cmake of these open source code, which will compile it to .la library. >>> >>> ..make? >>>> >>>> Then using this library, it compile my code. >>> >>> I assume from the context you mean make rather than cmake above. >>> >>> To run make (or any command) at run-time, use the combination of >>> add_custom_command and add_custom_target. Basically, >>> add_custom_command creates an OUTPUT file (say your library) at run >>> time, and add_custom_target file-depends on that file and creates a >>> CMake target corresponding to the custom command which you can add as >>> a dependency of your application target. This insures make will be run (if >>> the library is not up to date) before your application is built. >>> >> >> No, this does not work when the external command is a make process. >> The problem is that the "output" of add_custom_command() is a target >> with it's own dependencies. > > I don't understand your remark since the OUTPUT of add_custom_command > must refer to a file not a target, and there is a big distinction > between those two concepts in CMake. That's why I emphasize when > a file is indicated and when a target is indicated below. > >> The external make process must always run >> in order catch dependencies that only the external make knows about. >> The only way to make sure the make process always runs is to use >> add_custom_target(), but alas, add_custom_target does allow us to >> specify an output. >> >> See this thread from a few days ago: add_custom_command depends on >> output from add_custom_target. >> >> As far as I know, there is no satisfactory way to do use external >> makefiles with CMake. I'm all ears if anyone has suggestions. >> > > In the past I have been able to use an external set of Makefiles with > no problems. However, I eventually took my own advice and replaced > that method with one that used cmake. So I don't have any current > good examples, and my remarks below are from memory. However, I think > it should be completely straightforward to do what you like if you > read the cmake documentation for add_custom_command and > add_custom_target carefully. > > Here is schematically what you have to do: > > add_custom_command( > OUTPUT full_path_to_generated_library > COMMAND make > WORKING_DIRECTORY full_path to where Makefile is located > ) > > add_custom_target( > extern_lib > DEPENDS full_path_to_generated_library > ) > > add_executable(myexecutable myexcutable.c) > > target_link_libraries(myexecutable full_path_to_generated_library) > > add_dependencies(myexecutable extern_lib) > > In sum, target_link_libraries tells how to link the executable file > associated with the myexecutable target to the library _file_ > full_path_to_generated_library, add_dependencies makes sure the > _custom target_ extern_lib is built before the _target_ myexecutable is > built, and the _file_ DEPENDS of add_custom_target makes sure the > custom make command is run every time there is an attempt to build the > myexecutable (and therefore extern_lib) target. > > Please check my memory of the correct way to do this by using the > touch command. For example, if you touch one of the source files for > the external library, then I believe with the above scenario if you > subsequently run "make myexecutable", then the custom make command > should always be run (since it has no DEPENDS option), and therefore > the external library will automatically be rebuilt (assuming those > external Makefiles had done their dependencies properly), and > myexecutable relinked.
AFAIK, this can be simplified by dropping the custom command: add_custom_target( extern_lib COMMAND make WORKING_DIRECTORY full_path to where Makefile is located ) add_executable(myexecutable myexcutable.c) target_link_libraries(myexecutable full_path_to_generated_library) add_dependencies(myexecutable extern_lib) As the custom target is always out of date, make is invoked each time, and due to ADD_DEPENDENCIES(), it is invoked before the executable is examined for being out of date. If that results in a renewed external library the executable gets relinked. Additionally, the question if a custom command without DEPENDS clause does always run is avoided. Regards, Michael > Of course, use "make VERBOSE=1" to follow exactly what commands are > being run when testing file dependencies and associated target > dependencies with the touch command. Also, I believe it ultimately > would be a good idea to replace all builds of external libraries with > CMake-based builds since that gives you the most control of your > library organization. > > Alan > __________________________ > Alan W. Irwin > > Astronomical research affiliation with Department of Physics and Astronomy, > University of Victoria (astrowww.phys.uvic.ca). > > Programming affiliations with the FreeEOS equation-of-state implementation > for stellar interiors (freeeos.sf.net); PLplot scientific plotting software > package (plplot.org); the libLASi project (unifont.org/lasi); the Loads of > Linux Links project (loll.sf.net); and the Linux Brochure Project > (lbproject.sf.net). > __________________________ > > Linux-powered Science > __________________________ _______________________________________________ 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://www.cmake.org/mailman/listinfo/cmake
