I had to replace the following line in bme280.cpp in order to evaluate the temperatur as floating point. Or did I forget a compiler/linker option?

void BME280::readSensors(float *temperature, uint32_t *pressure, uint8_t *humidity) {
	
	//*temperature =  (((t_fine * 5 + 128) >> 8) / 100) ;
	*temperature =  ((float)((t_fine * 5 + 128) >> 8) / 100) ;