Re: [CMake] automatically re-generating makefiles
2009/3/16 Matthew Woehlke mw_tr...@users.sourceforge.net: Eric Noulard wrote: 2009/2/26 Alex Flint alex.fl...@gmail.com: Hi there, I've noticed that when I run make blah then the makefile is automatically re-generated if I've changed anything in CMakeLists.txt since the last time I built blah. However, if I add a new target to CMakeLists.txt then I have to run cmake manually or else I just get to rule to make foo. I think this already works if you call make and not make foo Because existing target do depends on cmake_check_build_system which should check for CMakeLists.txt changes (not verified just a guess). Actually, it's supposed to be possible to make the makefile itself dependent on something. You may be right but currently I do not see anything like a DIRECT dependency between Makefile and CMakeLists.txt in the CMake generated Makefile. The dependency exists (cmake_check_build_system) but it is somehow lazy, that is it is checked if you try to build any **already existing** target and not when trying to build a new target freshly added to a CMakeLists.txt. I think if this isn't working, either a: cmake isn't writing optimal dependencies for the makefiles themselves, Optimal depends in which sense. With the current scheme I would say that dependency is checked almost always when needed, with your propose scheme it would have to be checked always even if not needed, I would bet that unconditionnally checking dependency for non-existing target may be sub-optimal because it may cost you many unneeded check for rare case of needed checks. I may be wrong, may be some CMake developer, expert in Unix Makefiles generator dependency may shed the light on this? or b: 'make' could be doing better. I would say that make is an almost stupid tool, it does not check for unspecified dependency :-) Current CMake generated Makefiles lacks some rule like: Makefile : cmake_check_build_system My point of view is, I don't think it would be worth the cost to add it. -- Erk ___ 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
Re: [CMake] automatically re-generating makefiles
Eric Noulard wrote: 2009/3/16 Matthew Woehlke mw_tr...@users.sourceforge.net: I think if this isn't working, either a: cmake isn't writing optimal dependencies for the makefiles themselves, Optimal depends in which sense. With the current scheme I would say that dependency is checked almost always when needed, with your propose scheme it would have to be checked always even if not needed, I would bet that unconditionnally checking dependency for non-existing target may be sub-optimal because it may cost you many unneeded check for rare case of needed checks. Other than make help and make bogus_target, what would cause a check if this change was made that wouldn't cause it currently? Maybe I miss something? Makefile : cmake_check_build_system Shouldn't this rather be: Makefile: list of CMakeLists.txt, etc cmake_check_build_system ? ...in which case, the only thing that should get checked is if the CMakeLists.txt are newer than the Makefile. So in most cases this should be fast. -- Matthew Please do not quote my e-mail address unobfuscated in message bodies. -- You're on your own for the pony. -- Richard Hughes, on feature requests ___ 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
Re: [CMake] automatically re-generating makefiles
Matthew Woehlke wrote: Makefile : cmake_check_build_system Shouldn't this rather be: Makefile: list of CMakeLists.txt, etc cmake_check_build_system ? ...in which case, the only thing that should get checked is if the CMakeLists.txt are newer than the Makefile. So in most cases this should be fast. We need to run cmake_check_build_system first because make can not handle missing depend .h files. The check build system step makes sure the current set of depends won't kill make. It is also useful for getting around some other make limitations that I can not remember right now. -Bill ___ 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
Re: [CMake] automatically re-generating makefiles
Bill Hoffman wrote: Matthew Woehlke wrote: Makefile : cmake_check_build_system Shouldn't this rather be: Makefile: list of CMakeLists.txt, etc cmake_check_build_system ? ...in which case, the only thing that should get checked is if the CMakeLists.txt are newer than the Makefile. So in most cases this should be fast. We need to run cmake_check_build_system first because make can not handle missing depend .h files. I'm not saying to stop doing anything that is currently done. AFAICT, right now the Makefile itself does not have any dependencies; it seems that adding 'Makefile: build system files' with the rule from cmake_check_build_system would fix the original problem. So the question is if running cmake_check_build_system twice in a row can either be eliminated or kept reasonable. -- Matthew Please do not quote my e-mail address unobfuscated in message bodies. -- You're on your own for the pony. -- Richard Hughes, on feature requests ___ 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
Re: [CMake] automatically re-generating makefiles
Matthew Woehlke wrote: Bill Hoffman wrote: Matthew Woehlke wrote: Makefile : cmake_check_build_system Shouldn't this rather be: Makefile: list of CMakeLists.txt, etc cmake_check_build_system ? ...in which case, the only thing that should get checked is if the CMakeLists.txt are newer than the Makefile. So in most cases this should be fast. We need to run cmake_check_build_system first because make can not handle missing depend .h files. I'm not saying to stop doing anything that is currently done. AFAICT, right now the Makefile itself does not have any dependencies; it seems that adding 'Makefile: build system files' with the rule from cmake_check_build_system would fix the original problem. So the question is if running cmake_check_build_system twice in a row can either be eliminated or kept reasonable. I still don't get the original problem??? We used to have Makefile: build system files. It was removed when that work was pushed into cmake_check_build_system. -Bill ___ 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
Re: [CMake] automatically re-generating makefiles
Bill Hoffman wrote: I still don't get the original problem??? We used to have Makefile: build system files. It was removed when that work was pushed into cmake_check_build_system. Ah. Maybe it should come back? The original problem is: 'make foo' doesn't work after adding a target 'foo', because the Makefile needs to be regenerated to know about this target. It seems if Makefile depended on the build system files, this would cause Makefile to be regenerated, so 'make foo' would work in this instance. -- Matthew Please do not quote my e-mail address unobfuscated in message bodies. -- You're on your own for the pony. -- Richard Hughes, on feature requests ___ 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
Re: [CMake] automatically re-generating makefiles
Matthew Woehlke wrote: Bill Hoffman wrote: I still don't get the original problem??? We used to have Makefile: build system files. It was removed when that work was pushed into cmake_check_build_system. Ah. Maybe it should come back? The problem with Makefile: input-foo.txt input-bar.txt regenerate-rule is that when someone removes input-bar.txt from disk Make will refuse to run the regeneration rule. This is just a fundamental limitation of using make to build. AFAIK there is no way to implement the make my-new-target interface reliably. In the future we plan to create a cbuild tool to drive native builds and a corresponding CMake generator for it. That tool will be able to provide whatever fancy interface we want. Until then we are limited by the fact that make runs before CMake can look at the tree. -Brad ___ 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
Re: [CMake] automatically re-generating makefiles
Brad King wrote: AFAIK there is no way to implement the make my-new-target interface reliably. FYI, you can write the above like this: make rebuild_cache make my-new-target if you know that it is a new target. -Brad ___ 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
Re: [CMake] automatically re-generating makefiles
Brad King wrote: The problem with Makefile: input-foo.txt input-bar.txt regenerate-rule is that when someone removes input-bar.txt from disk Make will refuse to run the regeneration rule. Ah, wasn't thinking about that. Thanks for the info. -- Matthew Please do not quote my e-mail address unobfuscated in message bodies. -- You're on your own for the pony. -- Richard Hughes, on feature requests ___ 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
Re: [CMake] automatically re-generating makefiles
Eric Noulard wrote: 2009/2/26 Alex Flint alex.fl...@gmail.com: Hi there, I've noticed that when I run make blah then the makefile is automatically re-generated if I've changed anything in CMakeLists.txt since the last time I built blah. However, if I add a new target to CMakeLists.txt then I have to run cmake manually or else I just get to rule to make foo. I think this already works if you call make and not make foo Because existing target do depends on cmake_check_build_system which should check for CMakeLists.txt changes (not verified just a guess). Actually, it's supposed to be possible to make the makefile itself dependent on something. I think if this isn't working, either a: cmake isn't writing optimal dependencies for the makefiles themselves, or b: 'make' could be doing better. -- Matthew Please do not quote my e-mail address unobfuscated in message bodies. -- I don't question your existence -- God (seen on a church billboard) ___ 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
Re: [CMake] automatically re-generating makefiles
2009/2/26 Alex Flint alex.fl...@gmail.com: Hi there, I've noticed that when I run make blah then the makefile is automatically re-generated if I've changed anything in CMakeLists.txt since the last time I built blah. However, if I add a new target to CMakeLists.txt then I have to run cmake manually or else I just get to rule to make foo. This makes perfect sense but I was wondering if there is there any way to get cmake to put a catch-all rule in the Makefile that will cause CMakeLists.txt to be re-read even if a nonexistent target is specified on the commandline. Hence I would like to be able to add a target foo to CMakeLists.txt then just run make foo and cmake should be invoked to regenerate the makefile and the makefile should be invoked. I think this already works if you call make and not make foo Because existing target do depends on cmake_check_build_system which should check for CMakeLists.txt changes (not verified just a guess). Would you confirm it make with make (no target) ? If it works with make with no target but your added target is excluded from ALL I would say that you are currently stuck, because when you run make whatever_target make will look for that whatever_target before CMake gets a chance to be executed. What you ask for is somehow to force cmake to be run each time make is run. Another question is could you tell us which version of CMake do you use? This might sound pointless but I actually have a good motivation that I'd be happy to discuss if anyone is interested... Yes please tell us why you need that I currently cannot imagine your good motivations :-) -- Erk ___ 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
