Error: port expects axis but varray has none - Error: port expects axis but varray has none - 2026.1 English

Error: port expects axis but varray has none - Error: port expects axis but varray has none - 2026.1 English - UG1864

Vitis Functional Simulation User Guide (UG1864)

Document_ID

UG1864

Release_Date

2026-06-23

Version

2026.1 English

This error occurs if the kernel port uses an AXI4-Stream type (for example, hls::axis<int>) but the input varray does not have an axis configuration:

# Python
kernel = vfs.hlsKernel(input_files="stream_kernel.cpp", hls_function="my_func")
arr = va.array(np.array([1, 2, 3], dtype=np.int32), dtype=va.int32)  # no axis
result = kernel.run(arr)  # TypeError!

The error message suggests a set_axis() call or constructor to fix it:

TypeError: Input port 0 expects AXI-Stream axis sidebands (DataType:
'axis(int32)'), but the provided varray does not have an axis configuration.
...
Or add axis to an existing array:
  arr.set_axis(axis(w_user=0, w_id=0, w_dest=0))

Fix: Add the matching axis configuration:

arr.set_axis(va.axis())