problem with program

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Hello,

i have problem with program for 2048 like game K. It needs to be compilated with
$ gcc -std=c11 -Werror -Wall -Wconversion -lm But i got error and cant figure it out. Problem is with source file k.c here is screenshot Screenshot by Lightshot. It says return code is different than expected and 3 function were never used. Whats wrong there?
Any help would be appreciated. If i post it on wrong category im sorry.

Makefile.txt
main.c
k.h
ui.c
ui.h

here is k.c

#include <stdlib.h>

#include "k.h"

void add_random_tile(struct game *game){
    int row, col;
 // find random, but empty tile
    do{
        row = rand() % SIZE;
        col = rand() % SIZE;
    }while(game->board[row][col] != ' ');

    // place to the random position 'A' or 'B' tile
    if(rand() % 2 == 0){
        game->board[row][col] = 'A';
    }else{
        game->board[row][col] = 'B';
    }
}
bool is_game_won(const struct game game)
{
for (int i=0;i<4;i++) 
       {
	for(int j=0;j<4;j++) 
		{
		 if(game.board[i][j]=='K') return true;
		}
       }
       return false;
}

bool is_move_possible(const struct game game)
{
for (int i=0;i<4;i++){
    for(int j=0;j<4;j++){

		 if(game.board[i][j]==' ')  return true;
	}
}

for (int i=0;i<4;i++){ 

	for(int j=0;j<4;j++){    
		 if(game.board[i][j] == game.board[i][j+1])  return true;
	}

}
for (int i=0;i<4;i++){  

	for(int j=0;j<4;j++){

		 if(game.board[i][j] == game.board[i+1][j])
		 return true;
	}

}
        return false;
}
bool update(struct game *game, int dy, int dx){
	char znaky[12] = "ABCDEFGHIJK";
     int body[12] = { 2, 4, 8, 16, 32, 64, 128, 256, 512, 1024, 2048 };
     
    if (dx == 1 && dy == 0){
    for (int poc = 0; poc < 4; poc++ ){
          for (int row = 0; row < 4; row++){ 
           
             for (int col = 2; col >= 0; col--){
                if (game->board[row][col+1] == ' '){
                game->board[row][col+1] = game->board[row][col];
                game->board[row][col] = ' ' ; }
             }
             for (int abc = 0; abc < 12; abc++ ){
                for (int col = 2; col >= 0; col--){
                if (game->board[row][col+1] == znaky[abc] && game->board[row][col] == znaky[abc]){
                   game->board[row][col+1] = znaky[abc+1];
                   game->board[row][col] = ' ';
                   game->score = game->score + (2*body[abc]);}
                }
             }
             for (int col = 2; col >= 0; col--){
                if (game->board[row][col+1] == ' '){
                game->board[row][col+1] = game->board[row][col];
                game->board[row][col] = ' ' ; }
             }
          }
       }
    return true;   
    }
               
    else if (dx == -1 && dy == 0){ 
       for (int poc = 0; poc < 4; poc++ ){
          for (int row = 0; row < 4; row++){
            
             for (int col = 1; col < 4; col++){
                if (game->board[row][col-1] == ' '){
                game->board[row][col-1] = game->board[row][col];
                game->board[row][col] = ' ' ; }
             }
             for (int abc = 0; abc < 12; abc++ ){
                for (int col = 1; col < 4; col++){
                if (game->board[row][col-1] == znaky[abc] && game->board[row][col] == znaky[abc]){
                   game->board[row][col-1] = znaky[abc+1];
                   game->board[row][col] = ' ';
                   game->score = game->score + (2*body[abc]);}
                }
             }
             for (int col = 1; col < 4; col++){
                if (game->board[row][col-1] == ' '){ 
                game->board[row][col-1] = game->board[row][col];
                game->board[row][col] = ' ' ; }
             }
          }
       } 
    return true;             
    }

    else if (dx == 0 && dy == 1){ 
    for (int poc = 0; poc < 4; poc++ ){
          for (int col = 0; col < 4; col++){
          
             for (int row = 2; row >= 0; row--){  
                if (game->board[row+1][col] == ' '){
                game->board[row+1][col] = game->board[row][col];
                game->board[row][col] = ' ' ; }
             }
             for (int abc = 0; abc < 12; abc++ ){
                for (int row = 2; row >= 0; row--){
                if (game->board[row+1][col] == znaky[abc] && game->board[row][col] == znaky[abc]){
                   game->board[row+1][col] = znaky[abc+1];
                   game->board[row][col] = ' ';
                   game->score = game->score + (2*body[abc]);}
                }
             }
             for (int row = 2; row >= 0; row--){  
                if (game->board[row+1][col] == ' '){
                game->board[row+1][col] = game->board[row][col];
                game->board[row][col] = ' ' ; }
             }
          }
       }
    return true;             
    }

    else if (dx == 0 && dy == -1){
       for (int poc = 0; poc < 3; poc++ ){
          for (int col = 0; col < 4; col++){
          
             for (int row = 1; row < 4; row++){  
                if (game->board[row-1][col] == ' '){
                game->board[row-1][col] = game->board[row][col];
                game->board[row][col] = ' ' ; }
             }
             for (int abc = 0; abc < 12; abc++ ){
                for (int row = 1; row < 4; row++){
                if (game->board[row+1][col] == znaky[abc] && game->board[row][col] == znaky[abc]){
                   game->board[row+1][col] = znaky[abc+1];
                   game->board[row][col] = ' ';
                   game->score = game->score + (2*body[abc]);}
                }
             }
             for (int row = 1; row < 4; row++){  
                if (game->board[row-1][col] == ' '){ 
                game->board[row-1][col] = game->board[row][col];
                game->board[row][col] = ' ' ; }
             }
          }
       }
    return true;                      
    }
    else return false;
}

[Salem]

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