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Subject: Re: [PATCH 1/2] Compiler Attributes: add support for __fallthrough
 (gcc >= 7.1)
To: Nick Desaulniers <ndesaulniers@google.com>
Cc: Miguel Ojeda <miguel.ojeda.sandonis@gmail.com>,
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From: Bernd Petrovitsch <bernd@petrovitsch.priv.at>
Message-ID: <9c52827b-4783-8f39-9030-a166d5436f05@petrovitsch.priv.at>
Date: Mon, 22 Oct 2018 20:13:46 +0200
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Hi all!

On 22/10/18 19:54, Nick Desaulniers wrote:
> On Mon, Oct 22, 2018 at 10:50 AM Bernd Petrovitsch
> <bernd@petrovitsch.priv.at> wrote:
[...]
>> PS: clang++ errors with "fallthrough annotation in unreachable code" i=
f
>>     [[fallthrough]] is after an assert(). clang-devs there, please, th=
e
>>     fallthrough doesn't really generated code (I hope;-).
[...]
> Can you send me a link to a simple reproducer in godbolt (godbolt.org)
> and we'll take a look?

Does https://godbolt.org/z/2Y4zIo do it - I'm a godbolt-newbie?

For
----  snip  ----
#include <cassert>

int main(void)
{
  switch (1) {
  default:
    assert(0);
    [[fallthrough]];
  case 1:
    ;
  }
  return 0;
}
----  snip  ----
Just "clang++ -Wimplicit-fallthrough -Werror" it .....

MfG,
	Bernd
--=20
"I dislike type abstraction if it has no real reason. And saving
on typing is not a good reason - if your typing speed is the main
issue when you're coding, you're doing something seriously wrong."
    - Linus Torvalds

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