I investigating some weird behavior regarding arrays of const object. I'm not 100% sure what I'm observing, but it would appear that when adding objects to a const array, objects are not postblit-ed? Is this the expected behavior?

In this program, "S" is a struct that just prints when postblit is called:
//----
void main()
{
    S[] arr;
    foreach (i; 0 .. 5)
    {
        writeln(i);
        arr ~= S(i);
    }
}
//----
0
post
1
post
2
post
3
post
post
post
post
4
post
//----
Here, we can clearly see each element being postblit inserted. We can also see the array re-locating.

However, if we change "S[] arr;" to "const(S)[] arr;", then the output becomes:
//----
0
1
2
3
4
//----

Strange... right?

I was actually investigating the issue when trying to do a const array of refcounted. It was behaving scary weird...:

//----
alias RCI = RefCounted!(int, RefCountedAutoInitialize.no);
void main()
{
    const(RCI)[] arr;
    foreach (i; 0 .. 3)
    {
        foreach (j; 0 .. i)
            writefln("pay[%s]: %s", j, arr[j].refCountedPayload);

        auto a = const(RCI)(i);
        writefln("declared a: %s", a.refCountedPayload);

        foreach (j; 0 .. i)
writefln("pay[%s] before: %s", j, arr[j].refCountedPayload);

        arr ~= a;

        foreach (j; 0 .. i + 1)
writefln("pay[%s] after: %s", j, arr[j].refCountedPayload);
        writeln();
    }
    writeln("after");
    foreach (i; 0 .. 3)
        writeln("pay: ", arr[i].refCountedPayload);
}
//----
declared a: 0
pay[0] after: 0

pay[0]: 0
declared a: 1
pay[0] before: 1
pay[0] after: 1
pay[1] after: 1

pay[0]: 0
pay[1]: 0
declared a: 2
pay[0] before: 2
pay[1] before: 2
pay[0] after: 2
pay[1] after: 2
pay[2] after: 2

after
pay: 0
pay: 0
pay: 0
//----

See!?

The sole fact of declaring a on the stack modifies the values of all the elements in the array... And as soon as it goes out of scope, they all become 0 :/

The weirdest part (IMO), is that since "RefCountedAutoInitialize == no", the value "0" is not a result of an auto initialize: It is the actual allocated value of the RCI that is changing...

Changing it to non const "fixes" this, but I really don't even begin to fathom what is happening...

Thoughts?

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