reproduction Flowgraph for https://github.com/gnuradio/gnuradio/issues/4955

repro4955.grc

options:
  parameters:
    author: marcus
    catch_exceptions: 'True'
    category: '[GRC Hier Blocks]'
    cmake_opt: ''
    comment: ''
    copyright: ''
    description: ''
    gen_cmake: 'On'
    gen_linking: dynamic
    generate_options: no_gui
    hier_block_src_path: '.:'
    id: repro4955
    max_nouts: '0'
    output_language: cpp
    placement: (0,0)
    qt_qss_theme: ''
    realtime_scheduling: ''
    run: 'True'
    run_command: '{python} -u {filename}'
    run_options: run
    sizing_mode: fixed
    thread_safe_setters: ''
    title: Not titled yet
    window_size: (1000,1000)
  states:
    bus_sink: false
    bus_source: false
    bus_structure: null
    coordinate: [8, 8]
    rotation: 0
    state: enabled

blocks:
- name: samp_rate
  id: variable
  parameters:
    comment: ''
    value: '32000'
  states:
    bus_sink: false
    bus_source: false
    bus_structure: null
    coordinate: [208, 28.0]
    rotation: 0
    state: enabled
- name: var
  id: variable
  parameters:
    comment: ''
    value: '[float(x) for x in range(4)]'
  states:
    bus_sink: false
    bus_source: false
    bus_structure: null
    coordinate: [328, 28.0]
    rotation: 0
    state: enabled
- name: blocks_null_sink_0
  id: blocks_null_sink
  parameters:
    affinity: ''
    alias: ''
    bus_structure_sink: '[[0,],]'
    comment: ''
    num_inputs: '1'
    type: complex
    vlen: '1'
  states:
    bus_sink: false
    bus_source: false
    bus_structure: null
    coordinate: [416, 144.0]
    rotation: 0
    state: enabled
- name: blocks_vector_source_x_0
  id: blocks_vector_source_x
  parameters:
    affinity: ''
    alias: ''
    comment: ''
    maxoutbuf: '0'
    minoutbuf: '0'
    repeat: 'True'
    tags: '[]'
    type: complex
    vector: var
    vlen: '1'
  states:
    bus_sink: false
    bus_source: false
    bus_structure: null
    coordinate: [192, 124.0]
    rotation: 0
    state: enabled

connections:
- [blocks_vector_source_x_0, '0', blocks_null_sink_0, '0']

metadata:
  file_format: 1
  grc_version: v3.11.0.0git-646-g244e92c0

repro4955.svg