Fix synth_qft_line with 32 or more qubits#16004
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Cryoris merged 1 commit intoQiskit:mainfrom Apr 13, 2026
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…re qubits In the debug more, the previous code panicked (attempt to multiply with overflow) when raising 2_u32 to power 32 or more. And in the release mode, I believe, it silently produced incorrect circuits.
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Whoops good catch. It would be nice to have an approximation degree (= max. exponent) here, similar to the standard QFT. But I'm not sure how that influences the efficient decomposition, that'd have to be checked.
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…re qubits (#16004) (#16007) In the debug more, the previous code panicked (attempt to multiply with overflow) when raising 2_u32 to power 32 or more. And in the release mode, I believe, it silently produced incorrect circuits. (cherry picked from commit 32a368f) Co-authored-by: Alexander Ivrii <alexi@il.ibm.com>
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Summary
Discovered the bug when experimenting with Jake's script for running Sabre experiments.
In the debug more, the previous code panicked (attempting to multiply with overflow) when raising 2_u32 to power 32 or more. And in the release mode, I believe, the multiplication silently wrapped around, so we just obtained incorrect circuits.
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