https://issues.dlang.org/show_bug.cgi?id=21962

          Issue ID: 21962
           Summary: importC: Empty enums are accepted as valid code
           Product: D
           Version: D2
          Hardware: All
                OS: All
            Status: NEW
          Severity: major
          Priority: P1
         Component: dmd
          Assignee: nobody@puremagic.com
          Reporter: ibuclaw@gdcproject.org

As per C99 6.7.2.2, empty enum is invalid, and yet, dmd compiles it.
---
enum empty
{
};

enum
{
};

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