Messages in this thread | | | From | Miguel Ojeda <> | Date | Mon, 22 Oct 2018 15:39:47 +0200 | Subject | Re: [PATCH 1/2] Compiler Attributes: add support for __fallthrough (gcc >= 7.1) |
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On Mon, Oct 22, 2018 at 1:24 PM Miguel Ojeda <miguel.ojeda.sandonis@gmail.com> wrote: > > On Mon, Oct 22, 2018 at 12:53 PM Kees Cook <keescook@chromium.org> wrote: > > > > On Mon, Oct 22, 2018 at 2:41 AM, Miguel Ojeda > > <miguel.ojeda.sandonis@gmail.com> wrote: > > > > > * clang does *not* support the attribute in C. > > > > Well that's not good. :) > > I will see with clang if they plan to add it. >
So I have looked in the clang sources and I have seen that clang is already preparing for C2x: since clang >= 6 we can actually enable the C++-like attributes with "-fdouble-square-bracket-attributes" in C mode, which in turn makes the warning work in C mode and can be suppressed with [[fallthrough]]. This would give us the warning also in clang, which would be a win vs. the comments. Nick?
However, I don't see a way to enable [[fallthrough]] in C mode for gcc >= 7.1 -- from a quick look, the C parser does not know about [[]] attributes, so I don't think we can use [[fallthrough]] for both compilers (yet).
Cheers, Miguel
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