ARCHIVED TRAINING / Qiskit/qiskit

qiskit__qiskit-11272

This is a preserved training example. Membership in the current training wave has not been verified.

Problem statement

Barrier instruction ignores number of qubits when passed qubit operands as set
### Environment

- **Qiskit Terra version**: 0.45
- **Python version**: 3.9.*
- **Operating system**: Linux



### What is happening?

When a circuit is created with integer qubit operands and a barrier is applied with those operands as a set the barrier instruction is created for a single qubit operand.

### How can we reproduce the issue?

```python
from qiskit import QuantumCircuit
qc = QuantumCircuit(2)
qc.barrier({0, 1})
print(qc.data)
```
gives
```
>>> [CircuitInstruction(operation=Instruction(name='barrier', num_qubits=1, num_clbits=0, params=[]), qubits=(Qubit(QuantumRegister(2, 'q'), 0), Qubit(QuantumRegister(2, 'q'), 1)), clbits=())]
```

### What should happen?

I would expect (and the behaviour was this way in 0.44)

```
>>> [CircuitInstruction(operation=Instruction(name='barrier', num_qubits=2, num_clbits=0, params=[]), qubits=(Qubit(QuantumRegister(2, 'q'), 0), Qubit(QuantumRegister(2, 'q'), 1)), clbits=())]
```

Passing a list gives the expected behaviour
```python
qc.barrier([0, 1])
```
### Any suggestions?

_No response_

Training membership

opd_e4b_pure_v6a opd_e4b_pure_v6b opd_e4b_pure_v7 opd_e4b_pure_v7b

Task issues extracted from preserved verified_rft_messages training examples. This is not a verified current RL wave manifest.

Task and snapshot provenance

Snapshot captured 2026-11-12T17:06:59.476467+00:00 · Autoresearch-Arena/gemma-4-developer-agent

{
  "datasets": [
    "opd_e4b_pure_v6a",
    "opd_e4b_pure_v6b",
    "opd_e4b_pure_v7",
    "opd_e4b_pure_v7b"
  ],
  "examples": 24,
  "instance_id": "qiskit__qiskit-11272",
  "problem_statement": "Barrier instruction ignores number of qubits when passed qubit operands as set\n### Environment\r\n\r\n- **Qiskit Terra version**: 0.45\r\n- **Python version**: 3.9.*\r\n- **Operating system**: Linux\r\n\r\n\r\n\r\n### What is happening?\r\n\r\nWhen a circuit is created with integer qubit operands and a barrier is applied with those operands as a set the barrier instruction is created for a single qubit operand.\r\n\r\n### How can we reproduce the issue?\r\n\r\n```python\r\nfrom qiskit import QuantumCircuit\r\nqc = QuantumCircuit(2)\r\nqc.barrier({0, 1})\r\nprint(qc.data)\r\n```\r\ngives\r\n```\r\n>>> [CircuitInstruction(operation=Instruction(name='barrier', num_qubits=1, num_clbits=0, params=[]), qubits=(Qubit(QuantumRegister(2, 'q'), 0), Qubit(QuantumRegister(2, 'q'), 1)), clbits=())]\r\n```\r\n\r\n### What should happen?\r\n\r\nI would expect (and the behaviour was this way in 0.44)\r\n\r\n```\r\n>>> [CircuitInstruction(operation=Instruction(name='barrier', num_qubits=2, num_clbits=0, params=[]), qubits=(Qubit(QuantumRegister(2, 'q'), 0), Qubit(QuantumRegister(2, 'q'), 1)), clbits=())]\r\n```\r\n\r\nPassing a list gives the expected behaviour\r\n```python\r\nqc.barrier([0, 1])\r\n```\r\n### Any suggestions?\r\n\r\n_No response_",
  "repo": "Qiskit/qiskit",
  "source": "v2/experiments/train_data/opd_e4b_pure_v6a/verified_rft_messages.jsonl",
  "source_sha256": "f045b7ca5b3883a1e2eaee81e1c02a4a1b53dd7b7b36e98bacb2ba5823a15148"
}

{
  "captured_at": "2026-11-12T17:06:59.476467+00:00",
  "membership": "archived training",
  "membership_evidence": "Task issues extracted from preserved verified_rft_messages training examples. This is not a verified current RL wave manifest.",
  "name": "Preserved post-training task archive",
  "source": "Autoresearch-Arena/gemma-4-developer-agent",
  "source_revision": "016496de222aaafca0d4ee4c18efc63ba616f76e",
  "sources": [
    {
      "path": "v2/experiments/train_data/opd_e4b_cispo_v5/verified_rft_messages.jsonl",
      "sha256": "a43610ad0dfb6ace95375cfae09000f41afc0338cc925af870a4ade7a9b20c4c"
    },
    {
      "path": "v2/experiments/train_data/opd_e4b_hybrid_v3/verified_rft_messages.jsonl",
      "sha256": "bd326303eb127e8e5e08f03daf97bb88d79d19709d59f3f93f348bc56686a8df"
    },
    {
      "path": "v2/experiments/train_data/opd_e4b_onpolicy_v3/verified_rft_messages.jsonl",
      "sha256": "960c680e797e823a0d3a22f4b1d5ef60a72971373d703b877340b0c9126aaf68"
    },
    {
      "path": "v2/experiments/train_data/opd_e4b_pure_v6a/verified_rft_messages.jsonl",
      "sha256": "f045b7ca5b3883a1e2eaee81e1c02a4a1b53dd7b7b36e98bacb2ba5823a15148"
    },
    {
      "path": "v2/experiments/train_data/opd_e4b_pure_v6b/verified_rft_messages.jsonl",
      "sha256": "0f62460a9706eea5e1605255896f191ab00cb5706c5f1f2e1c293e9a718218dc"
    },
    {
      "path": "v2/experiments/train_data/opd_e4b_pure_v7/verified_rft_messages.jsonl",
      "sha256": "e37f7bd675322f3f81500b73559d60d5f602ca0537bf19f5cb06332c728c7b72"
    },
    {
      "path": "v2/experiments/train_data/opd_e4b_pure_v7b/verified_rft_messages.jsonl",
      "sha256": "b864bdc8695183433eef6e31cb8d33fad44ba3aded2170c1ade4ad5b2944ce23"
    },
    {
      "path": "v2/experiments/train_data/opd_e4b_self_audit_v4/verified_rft_messages.jsonl",
      "sha256": "0026023745afb8f3dc1c176dc7f7171157b4ad5a66656b524af218e8e19ceee6"
    },
    {
      "path": "v2/experiments/train_data/rft_e4b_aligned_v2/verified_rft_messages.jsonl",
      "sha256": "92a4515fee9d152b0d4c510ee3ce4caaaffe2003ba7584469f8027f174aab18c"
    },
    {
      "path": "v2/experiments/train_data/rft_v1/verified_rft_messages.jsonl",
      "sha256": "a42453ccd7ac7680b0a03865e8e7080bc8bf74c8d9d193b440c441ed46f8512b"
    },
    {
      "path": "v2/experiments/train_data/rft_v2/verified_rft_messages.jsonl",
      "sha256": "18f4b3bd7e651f83c6acab479c9475e3fa50dc652a384f309e97146983ac85ba"
    }
  ]
}