Wow - given the age of the most recent messages on here, I wondered if I would get a response.

Many thanks for responding so quickly and my problem is resolved.

[ Note I now also have PlatformIO installed and that compiled the sketch at the first attempt. I can't work out which version of the board it is using, as it uses different naming conventions, but I think it is the most recent. ]

Hi - I've been using MySensors for a while and have a growing HA capability now with my own controller and also Home Assistant.
I use NodeMCU ESP8266s for everything - basically, every node is a WiFi, MQTT Gateway. That all works fine.
This weekend, I came to build another node but it will no longer compile. I have spent many hours tearing down and re-installing the Arduino IDE but it continues to fail with the same error:

<pre>
In file included from c:\Users\mark\Documents\Arduino\libraries\MySensors/MySensors.h:441,
from C:\Users\mark\AppData\Local\Temp.arduinoIDE-unsaved2023015-9648-6o2zl8.84f1\GatewayESP8266\GatewayESP8266.ino:114:
c:\Users\mark\Documents\Arduino\libraries\MySensors/hal/architecture/ESP8266/MyMainESP8266.cpp: In function 'bool can_yield()':
c:\Users\mark\Documents\Arduino\libraries\MySensors/hal/architecture/ESP8266/MyMainESP8266.cpp:95:9: error: 'cont_can_yield' was not declared in this scope; did you mean 'can_yield'?
95 | return cont_can_yield(g_pcont);
| ^~~~~~~~~~~~~~
| can_yield
c:\Users\mark\Documents\Arduino\libraries\MySensors/hal/architecture/ESP8266/MyMainESP8266.cpp: In function 'void esp_yield_within_cont()':
c:\Users\mark\Documents\Arduino\libraries\MySensors/hal/architecture/ESP8266/MyMainESP8266.cpp:101:2: error: 'cont_yield' was not declared in this scope; did you mean 'can_yield'?
101 | cont_yield(g_pcont);
| ^~~~~~~~~~
| can_yield
c:\Users\mark\Documents\Arduino\libraries\MySensors/hal/architecture/ESP8266/MyMainESP8266.cpp: In function 'void loop_task(ETSEvent*)':
c:\Users\mark\Documents\Arduino\libraries\MySensors/hal/architecture/ESP8266/MyMainESP8266.cpp:199:26: error: invalid operands of types 'void' and 'int' to binary 'operator!='
199 | if (cont_check(g_pcont) != 0) {
| ~~~~~~~~~~~~~~~~~~~ ^~ ~
| | |
| void int
</pre>
The above is the basic ESP8266 Gateway with no sensors and the RF removed - so as basic as it can be!

I have tried all sorts of ways to hack it to bring the cont.h code in but I cannot get it to work.

Any help would be really appreciated as this is really critical for my home network. If I can't sort this out I will have to completely rebuild the whole system using something else - and I'm not even sure what that might be! My controller is now a couple of thousand lines of code and I have some home-grown integrations to Shelly devices and a heat pump...

Thanks,

Mark.