C - ben fuggveny warning:"control reaches end of non-void function [-Wreturn-type]" struct típusú fuggveny?

struct BmpData bmpfunc(){

char *i2c_device = "/dev/i2c-1";

int address = 0x77;

void *bmp = bmp180_init(address, i2c_device);

bmp180_eprom_t eprom;

bmp180_dump_eprom(bmp, &eprom);

bmp180_set_oss(bmp, 1);

if(bmp != NULL){

struct BmpData result;

float t = bmp180_temperature(bmp);

long p = bmp180_pressure(bmp);

float alt = bmp180_altitude(bmp);

printf(" t = %.2f, p = %lu, a= %.2f", t, p, alt);

result.a_t = t;

result.a_p = p;

result.b_alt = alt;

return result;

bmp180_close(bmp);

}

}

HOgy lehetne megoldani ezt a figyelmeztetest?