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From: "olafurw at gmail dot com" <gcc-bugzilla@gcc.gnu.org>
To: gcc-bugs@gcc.gnu.org
Subject: [Bug c++/105497] New: -Wswitch ignores [[maybe_unused]] for an enumerator
Date: Thu, 05 May 2022 15:37:11 +0000	[thread overview]
Message-ID: <bug-105497-4@http.gcc.gnu.org/bugzilla/> (raw)

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=105497

            Bug ID: 105497
           Summary: -Wswitch ignores [[maybe_unused]] for an enumerator
           Product: gcc
           Version: 11.3.0
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: c++
          Assignee: unassigned at gcc dot gnu.org
          Reporter: olafurw at gmail dot com
  Target Milestone: ---

enum class Button
{
    Left,
    Right,
    Middle,
    NumberOfButtons [[maybe_unused]]
};

int main()
{
    Button b = Button::Left;
    switch (b) {
        case Button::Left:
        case Button::Right:
        case Button::Middle:
            break;
//#ifdef __GNUC__
//        case Button::NumberOfButtons:
//            __builtin_unreachable();
//#endif
    }
}

https://godbolt.org/z/d5M5MYc45

No warning generated for Clang or MSVC but it does for GCC. Works with
__builtin_unreachable()

LLVM bug report about the same thing:
https://bugs.llvm.org/show_bug.cgi?id=36231

             reply	other threads:[~2022-05-05 15:37 UTC|newest]

Thread overview: 5+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2022-05-05 15:37 olafurw at gmail dot com [this message]
2022-05-05 15:40 ` [Bug c++/105497] " mpolacek at gcc dot gnu.org
2022-05-05 15:43 ` mpolacek at gcc dot gnu.org
2022-05-18 14:34 ` cvs-commit at gcc dot gnu.org
2022-05-18 14:36 ` mpolacek at gcc dot gnu.org

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