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From: "xmh970252187 at gmail dot com" <gcc-bugzilla@gcc.gnu.org>
To: gcc-bugs@gcc.gnu.org
Subject: [Bug c++/106291] New: Literal class can appear in the constant-expression of a declaration of a bit-field
Date: Thu, 14 Jul 2022 05:14:06 +0000	[thread overview]
Message-ID: <bug-106291-4@http.gcc.gnu.org/bugzilla/> (raw)

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=106291

            Bug ID: 106291
           Summary: Literal class can appear in the constant-expression of
                    a declaration of a bit-field
           Product: gcc
           Version: 13.0
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: c++
          Assignee: unassigned at gcc dot gnu.org
          Reporter: xmh970252187 at gmail dot com
  Target Milestone: ---

struct A{
    constexpr operator int(){
        return 8;
    }
};
struct B{
    int a:A{};
};

GCC rejects this example, with a diagnosis that
> error: width of bit-field 'a' has non-integral type 'A'

[expr.const] p9 explicitly permit this case. 
> If an expression of literal class type is used in a context where an integral constant expression is required, then that expression is contextually implicitly converted ([conv]) to an integral or unscoped enumeration type and the selected conversion function shall be constexpr.

Clang accepts this example

             reply	other threads:[~2022-07-14  5:14 UTC|newest]

Thread overview: 3+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2022-07-14  5:14 xmh970252187 at gmail dot com [this message]
2022-07-14  5:14 ` [Bug c++/106291] " xmh970252187 at gmail dot com
2022-07-14  5:20 ` pinskia at gcc dot gnu.org

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