[Issue 16352] dead-lock in std.allocator.free_list unittest

[via Digitalmars-d-bugs]

https://issues.dlang.org/show_bug.cgi?id=16352

safety0ff.bugz <safety0ff.b...@gmail.com> changed:

           What    |Removed                     |Added
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                 CC|                            |safety0ff.b...@gmail.com

--- Comment #6 from safety0ff.bugz <safety0ff.b...@gmail.com> ---
SharedFreeList.allocate looks ABA prone:

A thread does:
    do
    {
        oldRoot = _root; // atomic load
        if (!oldRoot) return allocateFresh(bytes);
        next = oldRoot.next; // atomic load
    }
    while (!cas(&_root, oldRoot, next));

But the value of `next` could have changed between the load and the cas.

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