https://issues.dlang.org/show_bug.cgi?id=20538

          Issue ID: 20538
           Summary: malformed enum definition compiles
           Product: D
           Version: D2
          Hardware: x86_64
                OS: Linux
            Status: NEW
          Severity: minor
          Priority: P1
         Component: dmd
          Assignee: nobody@puremagic.com
          Reporter: asumface@gmail.com

enum
{
    = 1
}

compiles since 2.082.1, according to run.dlang.io. UDAs for enum members were introduced in this release.

enum
{
    = 1,
    2
}

raises: Error: `2` is not a valid attribute for enum members

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