Summary
qasm3_to_qir fails on any program containing a delay instruction:
qbraid_qir.qasm3.exceptions.Qasm3ConversionError: Unsupported statement of type <class 'openqasm3.ast.DelayInstruction'>
raised from qbraid_qir/qasm3/visitor.py:672. pyqasm 1.2.1 parses and unrolls the same program without complaint (delay[100ns] q[0]; survives unroll() unchanged), so the gap is in the QIR visitor, not the parser.
Repro (qbraid-qir 0.6.0, pyqasm 1.2.1)
from qbraid_qir import qasm3_to_qir
qasm3_to_qir('OPENQASM 3.0;\ninclude "stdgates.inc";\nqubit[1] q;\nbit[1] c;\nx q[0];\ndelay[100ns] q[0];\nc[0] = measure q[0];\n')Impact
Seen in production on qbraid:qbraid:sim:qir-sv (2 jobs, 1 user, 2026-09-07): the job fails at submit with Failed to convert OpenQASM program to QIR: Unsupported statement of type <class 'openqasm3.ast.DelayInstruction'>.
Suggestion
For the simulators QIR targets a delay has no observable effect; dropping DelayInstruction (with a warning) would unblock these programs. If QIR consumers ever want timing, __quantum__qis__delay could be emitted instead, but nothing downstream reads it today.
Summary
qasm3_to_qirfails on any program containing adelayinstruction:raised from
qbraid_qir/qasm3/visitor.py:672. pyqasm 1.2.1 parses and unrolls the same program without complaint (delay[100ns] q[0];survivesunroll()unchanged), so the gap is in the QIR visitor, not the parser.Repro (qbraid-qir 0.6.0, pyqasm 1.2.1)
Impact
Seen in production on
qbraid:qbraid:sim:qir-sv(2 jobs, 1 user, 2026-09-07): the job fails at submit withFailed to convert OpenQASM program to QIR: Unsupported statement of type <class 'openqasm3.ast.DelayInstruction'>.Suggestion
For the simulators QIR targets a delay has no observable effect; dropping
DelayInstruction(with a warning) would unblock these programs. If QIR consumers ever want timing,__quantum__qis__delaycould be emitted instead, but nothing downstream reads it today.