On Tue, Jun 25, 2019 at 9:19 AM Peter Zijlstra <pet...@infradead.org> wrote: > > Can it build a kernel without patches yet? That is, why should I care > what LLVM does?
Having more than a single compiler is always a good idea. You benefit from more warnings, more tooling, a second implementation for reference/comparison, etc. As for what is the current state, I think they are close, specially for aarch64, but I let Nick, Nathan et. al. answer that! :-) (Cc'd). They had a talk in FOSDEM 2019 about it, too. Also CC'ing Luc since he changed sparse to stop ignoring the attribute so that __has_attribute() would work, but I am not sure if there has been further work on supporting it properly. > > Also note that C2x may get [[fallthrough]]. See N2267 and N2335. At > > that point, surely tools/IDEs/analyzers will support it :-) The > > question is whether we want to wait that long to replace the comments. > > #define __fallthrough [[fallthrough]] > > right? Yes and no. The exact spelling we use does not matter much. My point with that paragraph was that since C2x will (maybe) add fallthrough, as C++17 did, every compiler/analyzer/IDE/etc. that is still missing support for it will have to eventually add it even if they ignore GNU attributes. At that point, I would guess most will likely add all spellings too. Cheers, Miguel
