https://issues.dlang.org/show_bug.cgi?id=22930

          Issue ID: 22930
           Summary: importC: switch statement gives bogus unreachable code
                    warning
           Product: D
           Version: D2
          Hardware: All
                OS: All
            Status: NEW
          Keywords: ImportC
          Severity: normal
          Priority: P1
         Component: dmd
          Assignee: nobody@puremagic.com
          Reporter: duser@neet.fi
                CC: duser@neet.fi

with "dmd -wi":

int fn()
{
        switch (1)
        {
                case 2:
                        return 0;
        }
        return 0; // Warning: statement is not reachable
}

seems like any switch that doesn't have at least once case using break; or falling of the end will give this warning for code after it

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