 --> [ local path prefix ]/connection_direct/invalid_port_number.fpp:9:12
  |
9 |     c.pOut[1] -> c.pIn
  |            ^ invalid port number 1 for port c.pOut (max is 0)
  |
 ::: [ local path prefix ]/connection_direct/invalid_port_number.fpp:3:3
  |
3 |   output port pOut: P
  |   ------------------- port instance is specified here

