https://issues.dlang.org/show_bug.cgi?id=12602

          Issue ID: 12602
           Summary: [CTFE] Changes to an array slice wrapped in a struct
                    do not propogate to the original
           Product: D
           Version: D2
          Hardware: All
                OS: All
            Status: NEW
          Severity: normal
          Priority: P1
         Component: DMD
          Assignee: nobody@puremagic.com
          Reporter: dmitry.olsh@gmail.com

Simplified code, shows difference between R-T and C-T:

struct Result
{
    uint[] source;
}

auto wrap(uint[] r)
{
    return Result(r);
}

auto testWrap()
{
    uint[] dest = [1, 2, 3, 4];
    auto ra = wrap(dest[0..2]);
    auto rb = wrap(dest[2..4]);
    foreach (i; 0..2)
        rb.source[i] = ra.source[i];
    return dest;
}

@system void main()
{
    static y = testWrap();
    auto y2 = testWrap();
    import std.conv;
    assert(y == y2, text(y, " vs ", y2)); //[1, 2, 3 ,4] vs [1, 2, 1, 2]
}


Tested with DMD 9c34e808dd83ecf810a2f87c73c8d8a95e90b5cc

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