Question

both of these functions are (under my compiler at least) guaranteed to create a seg fault, yet i have no idea why. i really like their functionality and i have seen similar examples, so i am curious to know what is going wrong here or how to do what i think this actually does, which is passing a “level” into some function and then being able to manipulate its variable (eg lvl.lvl_cl[x][y][z] = some_number) and then pass it back for further use

any help is appreciated 🙂

typedef struct {
    int lvl_cl[500][500][50];
    char lvl_ch[500][500][50];
} level;

level plugh(level * in_lvl){
    in_lvl->lvl_cl[444][444][44]++; //it segfaults even if this line is removed
    return * in_lvl;
}

level foo(level inlvl){
    inlvl.lvl_cl[443][443][43]++;   //it segfaults even if this line is removed
    return inlvl;
}

int main(void){
    level world;
    plugh(&world);
    foo(world);
    return 0;
    }

Answer 1

Every time you call foo function it copies the whole world structure and it is quite big. Try to pass the pointer:

void foo(level *inlvl){
    inlvl->lvl_cl[443][443][43]++;
}