Bump CUDA-Q to 28f195f4 and skip QECCodeTester.checkBitflip - #778
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Moves the .cudaq_version pin from 90b0f4d8 to 28f195f4, picking up the CUDA-Q work merged since 2026-07-31. One test has to be skipped to take the bump. QECCodeTester.checkBitflip samples a kernel that is deliberately just `h(q); h(q)`, so that a bit_flip channel attached to "h" has two gates to act on. Since CUDA-Q enabled value semantics and quantum optimizations (NVIDIA/cuda-quantum#4993), quake-simplify cancels the back-to-back Hermitian pair and dqe removes the now-dead qubit allocation, so the kernel reaches the simulator with no qubits: "Sampling detected on a kernel with no qubits. Your kernel must have qubits to sample it." Cancelling those gates is not semantics-preserving under a noise model, because channels are keyed on the gate name and deleting the gates deletes the noise. There is currently no way to opt out from C++: NVIDIA/cuda-quantum#5048 added `disable_quantum_optimization` for Python kernels only, and the C++ equivalent, NVIDIA/cuda-quantum#5057, is still open. The skip records that dependency so the test can be restored when 5057 lands or the optimizations become noise-aware. The other two failures seen against CUDA-Q main in recent nightlies, app_examples.surface_code-1-quantinuum-emulate-test-distance-{3,5}, were already addressed by NVIDIA#776 and need no further change here. Nightly runs 31076816948 (2026-08-06) and 31152253601 (2026-08-07) show checkBitflip failing on all four arch x CUDA combinations in both the QEC and All-libs jobs, with Solvers and Docs green. Signed-off-by: Ben Howe <bhowe@nvidia.com>
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No conflicts. The nine commits since the last merge touch the realtime path again -- NVIDIA#769 serves HOST_CALL inline and retires the worker threads, queues, and CqrTransceiver; NVIDIA#759 adds the dynamic-DEM infrastructure that reshapes create_realtime_decoder around chunk expansion -- but none of it reaches the inproc_rpc path this branch removes: no reference to inproc_rpc, qec_realtime_session, or rpc_producer comes back, and none of the deleted sources reappear. NVIDIA#778 moves the CUDA-Q pin to 28f195f4, so verification needs a toolchain rebuilt at that commit. Signed-off-by: Melody Ren <melodyr@nvidia.com>
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Moves the .cudaq_version pin from 90b0f4d8 to 28f195f4, picking up the CUDA-Q work merged since 2026-07-31.
One test has to be skipped to take the bump. QECCodeTester.checkBitflip samples a kernel that is deliberately just
h(q); h(q), so that a bit_flip channel attached to "h" has two gates to act on. Since CUDA-Q enabled value semantics and quantum optimizations(NVIDIA/cuda-quantum#4993), quake-simplify cancels the back-to-back Hermitian pair and dqe removes the now-dead qubit allocation, so the kernel reaches the simulator with no qubits:
"Sampling detected on a kernel with no qubits. Your kernel must have
qubits to sample it."
Cancelling those gates is not semantics-preserving under a noise model, because channels are keyed on the gate name and deleting the gates deletes the noise. There is currently no way to opt out from C++: NVIDIA/cuda-quantum#5048 added
disable_quantum_optimizationfor Python kernels only, and the C++ equivalent, NVIDIA/cuda-quantum#5057, is still open. The skip records that dependency so the test can be restored when 5057 lands or the optimizations become noise-aware.The other two failures seen against CUDA-Q main in recent nightlies, app_examples.surface_code-1-quantinuum-emulate-test-distance-{3,5}, were already addressed by #776 and need no further change here.
Nightly runs 31076816948 (2026-08-06) and 31152253601 (2026-08-07) show checkBitflip failing on all four arch x CUDA combinations in both the QEC and All-libs jobs, with Solvers and Docs green.