[boost] [lockfree] Faulty (?) static assert

Subject: [boost] [lockfree] Faulty (?) static assert
From: Hartmut Kaiser (hartmut.kaiser_at_[hidden])
Date: 2012-09-01 15:45:22

Hey,

The lockfree::queue constructors raise a static assert if no capacity is
specified. This contradicts the member initialization code close to the
assert, for instance:

    queue(void):
        head_(tagged_node_handle(0, 0)),
        tail_(tagged_node_handle(0, 0)),
        pool(node_allocator(), has_capacity ? capacity : 0)
    {
        BOOST_STATIC_ASSERT(has_capacity);
        initialize();
    }

which implies that 'has_capacity' is allowed to be false. From what I can
see 'has_capacity' could be false, indeed, in particular if the queue is not
bounded in size.

Would changing this to

    queue(void):
        head_(tagged_node_handle(0, 0)),
        tail_(tagged_node_handle(0, 0)),
        pool(node_allocator(), has_capacity ? capacity : 0)
    {
        BOOST_STATIC_ASSERT(has_capacity || capacity);
        initialize();
    }

reflect the actual intention?

Regards Hartmut
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