Rolf Eike Beer wrote: > Stephen Kelly wrote: >> Rolf Eike Beer wrote: >> >> Given that you're gathering the versions of each feature availability >> >> anyway, and given that boost.config and qcompilerdetection.h have the >> >> same information, there is no need for all users of the module to run >> >> all these try_compiles for all projects. Think of the energy waste :)! >> >> >> >> I suggest you use CMAKE_CXX_COMPILER_ID and CMAKE_CXX_COMPILER_VERSION >> >> to hardcode the features. You could even do so for known compilers, >> >> and leave the try_compile stuff for not-known compilers if you really >> >> want to, but I don't think that's worthwhile maintenance. >> > >> > We already found out that this is a bad idea for Apple, >> >> No we didn't :). >> >> The AppleClang vs VanillaClang version issue is something that needs to >> be solved anyway. > > The "which c++ lib is used" one, too. So you can only score one point, > either this one or the one below ;)
Not really. The set of language features implemented by the compiler is independent of the stdlib implementation and completeness. > >> >> 4) >> >> >> >> The COMPILE_OPTIONS for clang+apple might have to include >> >> -stdlib=libc++ for binary compatibility reasons if any of the >> >> dependencies use c++11 std library API in their interface and use >> >> libc++. >> >> >> >> See what I wrote about that here: >> >> http://thread.gmane.org/gmane.comp.programming.tools.cmake.devel/5813 >> > >> > I don't see how this is different with and without C++11, so how does >> > it affect this module in a way that would not affect the user anyway? >> >> You might have to investigate, for example, how system c++ libraries are >> compiled. I'm not familiar enough with APPLE to know what kind of c++ >> libraries it comes with. > > Again, how does that affect this module? Yes, I see what you mean. I suppose this issue of std library implementation is orthogonal to your module. However, I think a complete 'CMake support for c++11' concept would include diagnostic of transitively incompatible stdlib implementations (because it can be a common problem nowadays as both libstdcxx and libcxx are in the wild as c++11 library implementations), *and* compiler feature enabling. I guess you're only shooting for the latter, and not the 'complete package', but as I wrote before, I still think you should modernize regarding COMPILE_OPTIONS and target properties anyway. Thanks, Steve. -- 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
