Compiling fails due to implicit casts from void to Object*

[IronWarrior]

The following error is produced when compiling:

error GD35A792B: cannot initialize return object of type 'JAISound *' with an rvalue of type 'void'

Pointing at the return line in this function in voice.cpp

JAISound* startMarioVoice_override(MSound* sound, u32 soundId, u16 unk, u8 unk2) {
	u8 voiceType = (u8)TMario_getVoiceStatus_override(gpMarioOriginal);
	return sound->startMarioVoice(soundId, unk, voiceType);
}

Which makes sense, as the function signature it is invoking is:

void startMarioVoice(u32, s16, u8);

I'm able to compile the BetterSunshineModule template without issue. I haven't modified any of the cmake files or configs...I'm guessing there's a setting somewhere that allows this kind of code?