https://issues.dlang.org/show_bug.cgi?id=19099

          Issue ID: 19099
           Summary: Struct with field that has postblit or destructor
                    makes struct assignable
           Product: D
           Version: D2
          Hardware: x86_64
                OS: Linux
            Status: NEW
          Severity: normal
          Priority: P1
         Component: dmd
          Assignee: nobody@puremagic.com
          Reporter: razvan.nitu1305@gmail.com

struct B
{
    //this(this) {}
    //~this() {}
    int a;
}

struct A
{
    B b;
    immutable int a;
    this(int b) { a = b;}
}

void main()
{
    import std.stdio : writeln;
    A a = A(2);
    writeln(a.a);
    A b = A(3);
    a = b;            // line 21
    writeln(a.a);
}

This code correctly yields : bug.d(21): Error: cannot modify struct a A with
immutable members

However, if the postblit or the destructor or commented (or both), the code compiles successfully and when ran it prints:

2
3

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