Void value not ignored Why does this throw the error: "void value not ignored as it ought to be

returning = printTemperature(returnLine);"

void printTemperature(DeviceAddress deviceAddress)
{
  float tempC = sensors.getTempC(deviceAddress);
  if (tempC == -127.00) {
    Serial.print("Error getting temperature");
     return 0;
  } else {
    return tempC;
  }
}


void loop(){

   delay(2000);
   feeding = printTemperature(feedLine);
   returning = printTemperature(returnLine);
    mySql;
    feeding = 0;
    returning = 0;
}


Both 'feeding' and 'returning' are declared as a float too.
printTemperature() is declared void (i.e., nothing returned) but it contains a return statement, and you've attempted to assign the (void) value. You probably meant to declare the function as 'float'.