Hi, Given that Integrity seems to be the only tool-chain missing <version> in dev, I propose the following policy going forward:
> To detect post-C++17 library features, we require that <version> exists. That means that if <version> does not exist, we will not detect post-C++17 library features on that platform, even if they should exist. Practically, this means that qglobal.h (or one if it's offspring) would contain #if __has_include(<version>) # include <version> # unconditionally and we will detect post-C++17 library features only this way, going forward: #ifdef __cpp_lib_foo # include <foo> #endif and no longer this way: #if __has_include(<foo>) && __cplusplus > 201703L # include <foo> #endif To not break existing uses, however, existing checks that do the __has_include dance should not be cleaned up before we require the resp. library feature unconditionally. What do you think? Thanks, Marc On 06.11.22 19:58, Marc Mutz via Development wrote: > Hi all, > > [https://bugreports.qt.io/browse/QTBUG-108228 for details] > > After looking at libc++, libstdc++ and MS STL's <version>, it seemed > like it wouldn't #error out if #included in a C++17 project. So I've > kicked off a precheck on Gerrit, and so far, it looks like Integrity is > the only tool-chain that doesn't have a <version> header, yet: > > https://codereview.qt-project.org/c/qt/qtbase/+/441821 > > On other tool-chains, it appears to be usable in C++17 builds, too. > > I'll ask our Integrity experts to find out whether there are any plans > by GHS to add this header before their next major release, or as a > patch that Qt users could apply to their installation. > > Thanks, > Marc > -- Marc Mutz <marc.m...@qt.io> Principal Software Engineer The Qt Company Erich-Thilo-Str. 10 12489 Berlin, Germany www.qt.io Geschäftsführer: Mika Pälsi, Juha Varelius, Jouni Lintunen Sitz der Gesellschaft: Berlin, Registergericht: Amtsgericht Charlottenburg, HRB 144331 B _______________________________________________ Development mailing list Development@qt-project.org https://lists.qt-project.org/listinfo/development
