Fix non-determinism in toposort by using input order as a tie-breaker#998
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copybara-service[bot] merged 1 commit intomainfrom May 9, 2026
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Fix non-determinism in toposort by using input order as a tie-breaker#998copybara-service[bot] merged 1 commit intomainfrom
toposort by using input order as a tie-breaker#998copybara-service[bot] merged 1 commit intomainfrom
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generate_bindings before passing to toposorttoposort by using input order as a tie-breaker
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When `toposort` has multiple nodes ready to process (no remaining predecessors), it puts them in a `BinaryHeap` and uses the `preferred_order` closure to sort them. If the closure says two nodes are equal, their order in the heap depended on `HashMap` iteration order, which is non-deterministic. We fix this by recording each node's index in the input iterator. If the closure returns `Equal`, we now fall back to comparing these input indices, preferring nodes that came first. This makes the sort fully deterministic. PiperOrigin-RevId: 912985573
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Fix non-determinism in
toposortby using input order as a tie-breakerWhen
toposorthas multiple nodes ready to process (no remainingpredecessors), it puts them in a
BinaryHeapand uses thepreferred_orderclosure to sort them. If the closure says two nodes are equal, their order in
the heap depended on
HashMapiteration order, which is non-deterministic.We fix this by recording each node's index in the input iterator. If the
closure returns
Equal, we now fall back to comparing these input indices,preferring nodes that came first. This makes the sort fully deterministic.