At FOSDEM 2018, there will be a talk on "The free toolchain for the STM8" in the "Embedded, mobile and automotive devroom".
The talk in the will be 2018-02-03 11:00 in room UD2.218A at the Université libre de Bruxelles.
There has been a lot of recent progress, from the speed optimizations in SDCC to the on-target-debugging support via OpenOCD and GDB.
I will also be around for discussions during that weekend.
More details on the talk can be found at: