[Discuss-gnuradio] Message inputs and hierachical block: incompatibility introduced in GNU Radio 3.7.9

[Piotr Krysik]

Hi all,

In GNU Radio version 3.7.8 message inputs of hierarchical blocks were
created from python level with:
   self.message_port_register_hier_out("msg_in")

Starting (most probably) from GNU Radio 3.7.9 message inputs are created
with:
   self.message_port_register_hier_in("msg_in")

This leads to incompatibility. I can't now distribute to the users
python code of hierarchical blocks generated with GRC because for some
of them it won't work (if they don't use the same GNU Radio version as I
do). Compilation of GRC files to python with grcc during building is not
an option as it doesn't work reliably yet and it will lead to higher
level of problems.

Currently I manually added this code to my hierarchical blocks in order
to make them work on with GNU Radio earlier than 3.7.9:

  from distutils.version import LooseVersion as version

  if version(gr.version()) >= version('3.7.9'):
    self.message_port_register_hier_in("msg_in")
  else:
    self.message_port_register_hier_out("msg_in")

Is it possible to fix this problem for example on the level GRC - so it
generate code that is compatible with GNU Radio versions < 3.7.9 and
>=3.7.9?

Best Regards,
Piotr Krysik