Help compiling code

[Werewolf]

Hi,

I have written the code of my first chess engine after getting some help with ChatGPT.

It’s a simple brute force engine and the code is about 2 sides of A4.

However, when I try to compile in Clang, I get error after error. I think it’s not the code, which has been checked, but my use of Clang.

Can someone recommend a simple way forward? I’m open to any suggestions

Thanks

[smatovic]

If it is not your code then check for library functions and the according header includes, like

Code: Select all

#include <stdio.h>      /* for print and scan */
#include <stdlib.h>     /* for malloc free */
#include <string.h>     /* for string compare */ 

If you use non standard libraries you have to specify in compiler, e.g. add "-lm" for libmath.

Take a look into my simple Makefile, maybe you find there your missing part:

https://gitlab.com/smatovic/ZetaDva/-/b ... type=heads

--
Srdja

[gaard]

Hi,

I have written the code of my first chess engine after getting some help with ChatGPT.

It’s a simple brute force engine and the code is about 2 sides of A4.

However, when I try to compile in Clang, I get error after error. I think it’s not the code, which has been checked, but my use of Clang.

Can someone recommend a simple way forward? I’m open to any suggestions

Thanks

How did you check the code? What are the errors?

[Werewolf]

Hi,

I have written the code of my first chess engine after getting some help with ChatGPT.

It’s a simple brute force engine and the code is about 2 sides of A4.

However, when I try to compile in Clang, I get error after error. I think it’s not the code, which has been checked, but my use of Clang.

Can someone recommend a simple way forward? I’m open to any suggestions

Thanks

How did you check the code? What are the errors?

Yes you're right to question my code. I am a total beginner and probably haven't done a very good job.
If you have comments I have pasted the code below. Also now I will try other compilers as I'm getting in a twist with Clang



Sept 2024 Carl Bicknell
BRUTEFORCE 001

#include <stdio.h>
#include <stdlib.h>
#include <windows.h> // For Windows threads
#include <string.h> // Add this line for string functions like strncmp

// Basic board and piece constants
int board[8][8]; // Simple 2D board array representation
int piece_values[] = {100, 320, 330, 500, 900}; // Pawn, Knight, Bishop, Rook, Queen

// Evaluation function: simple piece count + bonuses for king safety, castling, etc.
int evaluate() {
int score = 0;
// Basic material evaluation + simple central pawn bonus and bishop pair
return score;
}

// Basic move generation: Generate legal moves (simplified for demo purposes)
void generate_moves() {
// Move generation code here
}

// Minimax Search: Fixed-depth search
int minimax(int depth, int isMaximizing) {
if (depth == 0) return evaluate();
if (isMaximizing) {
int best = -10000;
generate_moves(); // Replace with proper move generation
best = minimax(depth - 1, 0);
return best;
} else {
int best = 10000;
generate_moves();
best = minimax(depth - 1, 1);
return best;
}
}

// Thread function for search
DWORD WINAPI threaded_search(LPVOID arg) {
int depth = *(int*)arg;
int score = minimax(depth, 1); // Run minimax search
return 0;
}

// UCI Protocol Handler
void uci_loop() {
char input[2000];
while (1) {
fgets(input, 2000, stdin);
if (strncmp(input, "uci", 3) == 0) {
printf("id name BruteChess\n");
printf("id author YourName\n");
printf("uciok\n");
} else if (strncmp(input, "isready", 7) == 0) {
printf("readyok\n");
} else if (strncmp(input, "position", 8) == 0) {
// Handle position setup
} else if (strncmp(input, "go", 2) == 0) {
// Start search with threads
HANDLE threads[64]; // Array of threads
int depth = 5; // Example depth
for (int i = 0; i < 64; i++) {
threads = CreateThread(NULL, 0, threaded_search, &depth, 0, NULL);
}
// Wait for threads to finish
WaitForMultipleObjects(64, threads, TRUE, INFINITE);
printf("bestmove e2e4\n"); // Dummy move, replace with actual best move
} else if (strncmp(input, "quit", 4) == 0) {
break;
}
}
}

int main() {
printf("Chess Engine Ready\n");
uci_loop();
return 0;
}

[Mike Sherwin]

Hi,

I have written the code of my first chess engine after getting some help with ChatGPT.

It’s a simple brute force engine and the code is about 2 sides of A4.

However, when I try to compile in Clang, I get error after error. I think it’s not the code, which has been checked, but my use of Clang.

Can someone recommend a simple way forward? I’m open to any suggestions

Thanks

How did you check the code? What are the errors?

Yes you're right to question my code. I am a total beginner and probably haven't done a very good job.
If you have comments I have pasted the code below. Also now I will try other compilers as I'm getting in a twist with Clang



Sept 2024 Carl Bicknell
BRUTEFORCE 001

#include <stdio.h>
#include <stdlib.h>
#include <windows.h> // For Windows threads
#include <string.h> // Add this line for string functions like strncmp

// Basic board and piece constants
int board[8][8]; // Simple 2D board array representation
int piece_values[] = {100, 320, 330, 500, 900}; // Pawn, Knight, Bishop, Rook, Queen

// Evaluation function: simple piece count + bonuses for king safety, castling, etc.
int evaluate() {
int score = 0;
// Basic material evaluation + simple central pawn bonus and bishop pair
return score;
}

// Basic move generation: Generate legal moves (simplified for demo purposes)
void generate_moves() {
// Move generation code here
}

// Minimax Search: Fixed-depth search
int minimax(int depth, int isMaximizing) {
if (depth == 0) return evaluate();
if (isMaximizing) {
int best = -10000;
generate_moves(); // Replace with proper move generation
best = minimax(depth - 1, 0);
return best;
} else {
int best = 10000;
generate_moves();
best = minimax(depth - 1, 1);
return best;
}
}

// Thread function for search
DWORD WINAPI threaded_search(LPVOID arg) {
int depth = *(int*)arg;
int score = minimax(depth, 1); // Run minimax search
return 0;
}

// UCI Protocol Handler
void uci_loop() {
char input[2000];
while (1) {
fgets(input, 2000, stdin);
if (strncmp(input, "uci", 3) == 0) {
printf("id name BruteChess\n");
printf("id author YourName\n");
printf("uciok\n");
} else if (strncmp(input, "isready", 7) == 0) {
printf("readyok\n");
} else if (strncmp(input, "position", 8) == 0) {
// Handle position setup
} else if (strncmp(input, "go", 2) == 0) {
// Start search with threads
HANDLE threads[64]; // Array of threads
int depth = 5; // Example depth
for (int i = 0; i < 64; i++) {
threads = CreateThread(NULL, 0, threaded_search, &depth, 0, NULL);
}
// Wait for threads to finish
WaitForMultipleObjects(64, threads, TRUE, INFINITE);
printf("bestmove e2e4\n"); // Dummy move, replace with actual best move
} else if (strncmp(input, "quit", 4) == 0) {
break;
}
}
}

int main() {
printf("Chess Engine Ready\n");
uci_loop();
return 0;
}

Best to scrap that and start super simple with something that you totally understand.

Here's an example to start with. Don't worry about communicating with a protocol at first. Just get a console version working.

Code: Select all

enum { EXIT, GETCMD, SEARCH, MOVE };

struct Move
{
    char fromSquare;
    char toSquare;
    char fromType;
    char toType;
}; 

void StartSearch(Move* m) 
{
    mode = MOVE;
}   

void GameMove(Move* m) 
{
    mode = GETCMD;
}    

void Initialize() 
{
    mode = GETCMD;
}

void GetCommand() 
{

}

int main() 
{
    Move move;

    Initialize();

    while (mode != EXIT)
    {
        if (mode == GETCMD) GetCommand();
        if (mode == SEARCH) StartSearch(&move);
        if (mode == MOVE) GameMove(move);
    }
    
    return 0;
}

[Bo Persson]

// Start search with threads
HANDLE threads[64]; // Array of threads
int depth = 5; // Example depth
for (int i = 0; i < 64; i++) {
threads = CreateThread(NULL, 0, threaded_search, &depth, 0, NULL);
}

The main problem is here, when the loop tries to assign to the whole array at once. Use

Code: Select all

threads[i] = ...

instead to assign individual members.

The only other warning I see is in

Code: Select all

int score = minimax(depth, 1);

where the compiler thinks it might be an error to compute score, but never use it for anything.

[Werewolf]

Thanks everyone.

I decided to start small and go from there. In the spirit of Brute Force, I got a fully working noughts and crosses program working this morning that calculates all possible moves before playing (perfectly). It was multithreaded at 16 threads.

Eventually I'll work towards chess.