https://issues.dlang.org/show_bug.cgi?id=17753

          Issue ID: 17753
           Summary: IN6_IS_ADDR_UNSPECIFIED and friends should accept
                    const(in6_addr)*
           Product: D
           Version: D2
          Hardware: All
                OS: All
            Status: NEW
          Severity: normal
          Priority: P1
         Component: phobos
          Assignee: nobody@puremagic.com
          Reporter: shachar@weka.io

These are a bunch of macros in the C headers. When translated to D, they were transformed into functions. As such, they should declare their constness, or calling them becomes a problem from certain contexts.

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