December 03, 2018
https://issues.dlang.org/show_bug.cgi?id=19462

          Issue ID: 19462
           Summary: A noisy warning about toHash will occur
           Product: D
           Version: D2
          Hardware: x86_64
                OS: Windows
            Status: NEW
          Severity: regression
          Priority: P1
         Component: druntime
          Assignee: nobody@puremagic.com
          Reporter: zan77137@nifty.com

Noisy warnings now occur with this code (in dmd/druntime/Phobos master):


------------------------------------
struct Foo
{
        Object _p;
        alias _p this;
}

struct Bar
{
        import std.typecons: Proxy;
        Object foo;
        mixin Proxy!foo;
}

void main(){}
------------------------------------

Maybe, the origin is hashOf template function called by Proxy.

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