struct postblit not called, but still destructed

[monarch_dodra]

On Sunday, 19 January 2014 at 19:24:23 UTC, Benjamin Thaut wrote:
> Yes this looks like a bug to me. Please file a bug report at 
> https://d.puremagic.com/issues/
>
> Kind Regards
> Benjamin Thaut

Here is a reduced case:

//----
import std.stdio;

struct B
{
	A sup;

	this(A a)
	{
		writeln("Here");
		sup = a;
		writeln("There");
	}
}

struct A
{
	static int count;

	this(int n)
	{
		writeln("A.this()");
	}

	this(this)
	{
		writeln("A.this(this)");
	}

	~this()
	{
		writeln("A.~this()");
	}
}

void main()
{
	A a = A(1);

	writeln("Start");
	B b = B(a);
	writeln("End");
}
//----
A.this()
Start
A.this(this)
Here
A.this(this) //!!!
A.~this()    //!!!
There
A.~this()
End
A.~this()
A.~this()
//----

I think the behavior is not *strictly* incorrect: When you write:
sup = a;

it triggers a postblit of "a" into "sup". To do said postblit, 
you destroy sup. It's the way it works :/

Arguably, since it is initialization, we could avoid the 
destruction altogether, but it's not strictly *wrong*.

I'll file it as an ER, and try to get Kenji on it.