Use a dynamic bound for the queue

[oriongonza]

If the queue is at capacity (100) and we push something to it it will grow, but the push_bounded will still block when there's plenty of space left.

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[ehuss]

Thanks for the PR! I don't think the capacity of VecDeque is guaranteed to be exact. Can you say more about why this is needed?

[oriongonza]

This is not exactly needed, but this solves the issue mentioned above, the unfortunate situation when the sender blocks when it doesn't need to.

I don't think the capacity of VecDeque is guaranteed to be exact

https://github.com/rust-lang/cargo/blob/master/src/cargo/core/compiler/job_queue/mod.rs#L485 I don't think you care ;)

[weihanglo]

but the push_bounded will still block when there's plenty of space left.

The bound is expected to be static if I understand the code correctly.

Why does this need to support a dynamic bound? Any Cargo bad behavior you saw?