On Mon, Oct 22, 2018 at 7:36 PM Nick Desaulniers <ndesaulniers@xxxxxxxxxx> wrote: > > On Sun, Oct 21, 2018 at 10:14 AM Miguel Ojeda > <miguel.ojeda.sandonis@xxxxxxxxx> wrote: > > > > of its kind) to deal with this: [[fallthrough]] is meant to be > > a new control keyword in the form of an extension. > > I think we can leave the details about the [[]] notation out. IIUC, > it's only applicable to C++. No, because C++ is the driving force for the standard attributes syntax; i.e. C2x is adding them because of the syntax published by C++17; and possibly gcc 7.1 added support for fallthrough (and comment parsing) due to C++17 too. Basically, it is a small paragraph explaining how this came to be. > > +#if __has_attribute(__fallthrough__) > > +# define __fallthrough __attribute__((__fallthrough__)) > > +#else > > +# define __fallthrough > > While this is in the correct format as the other attributes in this > file, I think this particular attribute is a special case, because of > the variety of fallbacks and differing support for them. I'd like to No, is it the correct format because we cannot add support for the other syntax in gcc; so the best way to proceed is to simply wait until clang supports the GNU attribute in C mode. The tooling, of course, is another matter and independent of this. > see in the commit message maybe a list of tools we'd like to support Yes, I already said I would write it in one of the other threads. > and links to the feature requests/bug reports for them. I acknowledge > it's more work to file bugs, but it's being a good open source > citizen, IMO. Who said we aren't going to do it? :-) I was actually in the process of checking which OSS tools supported what and how easy it was to fix in each of them (gcc's [[...]] syntax, clang's GNU and C++ attrs in C mode, cppcheck's fallthrough support...), but it takes time; I prefer to do the research beforehand; so that the submitted bug reports are better/more precise/more helpful, etc. However, you already sent the LLVM report (without mentioning this thread or me, nor the -fdouble-square-bracket-attributes clang flag that I mentioned). That is a bit rude :-) Please take things a little easier, there is no need to rush stuff. If I didn't have submitted the LLVM bug report is because I hadn't finish looking at the issue. In general, I think it is polite (and also more productive to avoid duplicating efforts) to first ask whoever is working on something before you rush to do it... > > I'm also curious which is the first version of GCC to support the > comment format? gcc 7.1 started everything. It is stated in the commit message and several messages/threads already. Again, please pause, relax and read a bit before sending stuff around :-) Cheers, Miguel
