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digitalmars.D.bugs - [Issue 19073] New: core.internal.hash should not bitwise hash


          Issue ID: 19073
           Summary: core.internal.hash should not bitwise hash
                    representations of floating point numbers
           Product: D
           Version: D2
          Hardware: All
                OS: All
            Status: NEW
          Severity: normal
          Priority: P1
         Component: druntime
          Assignee: nobody puremagic.com
          Reporter: n8sh.secondary hotmail.com

Currently `hashOf(float)` coalesces all NaNs to have the same hash code when
they are hashed directly, but not when they appear as fields of structs or as
elements of static arrays or as elements of dynamic arrays.

void main()
    import core.internal.hash : hashOf;
    static struct S { float value; }

    assert(hashOf(float.nan) == hashOf(-float.nan)); // Passes.
    assert(hashOf(S(float.nan)) == hashOf(S(-float.nan))); // Fails!

Jul 10 2018