https://issues.dlang.org/show_bug.cgi?id=23801

          Issue ID: 23801
           Summary: ImportC: enumeration constant does not fit in an int
           Product: D
           Version: D2
          Hardware: All
                OS: All
            Status: NEW
          Severity: normal
          Priority: P1
         Component: dmd
          Assignee: nobody@puremagic.com
          Reporter: dave287091@gmail.com

The system library libdispatch on macOS has an enumeration constant that does not fit in an int. It is more or less defined as so:

enum {
    DISPATCH_WALLTIME_NOW = ~1ull,
};

C11 is clear on the subject - enumeration constants must fit in an int. However, clang, gcc and likely other compilers accepted larger constants as an extension.

Additionally, C23 has greatly changed the rules and so the above is now valid when compiling with that standard.

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