Will code compiled for an STM8L151G3 execute properly on an STM8L151G4 assuming there are no I/O differences?

[LGoye.1]

Trying to work around chip shortage with a single executable

[WilkoL]

The only difference is that the G4 has double the flash/ram/eeprom of a G3. So yes, I seen no reason why it would not work. If you went the other way, it could be that you ran out of memory.