fec: cc enc/dec in ber_curve_gen example yields different results in 3.8

[mormj]

When running the ber_curve_gen.grc example in gr-fec, the convolutional coder results do not look right at all as compared to the graph produced in 3.7

Here is the graph produced under 3.8:

Under 3.7

The parameters for the objects in the .grc file all look the same between both

[jdemel]

It looks like the CC code fails. Besides, the curves seem to be correct. If the simulation would run for a couple more hours, I'd guess, those curves would look the same. I suggest to investigate, why the CC code fails. What about CC code tests? Do they pass?

[fmagno]

There seems to be an issue with the example fec/examples/fecapi_cc_decoders.grc that could be related: