https://issues.dlang.org/show_bug.cgi?id=18997

          Issue ID: 18997
           Summary: extern(C++) mangling incorrect for wchar_t
           Product: D
           Version: D2
          Hardware: All
                OS: All
            Status: NEW
          Severity: major
          Priority: P1
         Component: dmd
          Assignee: nobody@puremagic.com
          Reporter: turkeyman@gmail.com

DMD treats wchar_t like an alias, which leads to incorrect mangling. MSVC mangles as '_W', and posix as 'w'.

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