Odd Bug!

[JPulham]

Hi, I have an odd bug. I started with just the if statments below (not embeded in 'validation if's')
The game is a game where you click a colored block it disappears with the surround in blocks of the same color. However, when I call erase inside this function, it causes an illegal operation

Can anyone see anything wrong with this code?

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void Erase(int x, int y, int ex)
{
    int tokill = g_blocks[x][y];
    g_blocks[x][y] = BLOCK_EMPTY;
    //kill the linked ones
    if(((x + 1) <= 9) && (ex != EXCLUDE_LEFT))
    {
        if(g_blocks[x + 1][y] == tokill)
        {
            Erase(x + 1, y,EXCLUDE_LEFT);
        }
    }
    if(((x - 1) >= 0) && (ex != EXCLUDE_RIGHT))
    {
        if(g_blocks[(x - 1)][y] == tokill)
        {
            Erase(x - 1, y,EXCLUDE_RIGHT);
        }
    }
    if(((y + 1) <= 15) && (ex != EXCLUDE_BELOW))
    {
        if(g_blocks[x][(y + 1)] == tokill)
        {
            Erase(x, y + 1,EXCLUDE_BELOW);
        }
    }
    if(((y - 1) >= 0) && (ex != EXCLUDE_ABOVE))
    {
        if(g_blocks[x][(y - 1)] == tokill)
        {
            Erase(x, y - 1,EXCLUDE_ABOVE);
        }
    }
}

[ErUs]

either step through with a debugger and find the exact line it fails on, or put lots and lots of printf()'s in theres and then see where the problem is

[Acki]

Hmm, I'm not really sure, but one thing makes me curious...
For example this line:

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if(((x + 1) <= 9) && (ex != EXCLUDE_LEFT))

x+1 is the field to the right, isn't it ???
So should it not be like this:

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if(((x + 1) <= 9) && (ex == EXCLUDE_LEFT))

the same for all other comparisons...

[JPulham]

@acki:
I put that code in after it started failing... to try and validate... but it didn't work.

I'll just have to step through, I did try some message boxes but I just thought it was an odd bug and wondered if there was an obvious error only I couldn't see

[Acki]

Well, it's not easy to debug a code snippet, since it's a recursive calling function and we don't know about the rest of the code...

If you don't get it on your own, it will be a great help for us to have the whole code (maybe as download) so we can check it !!!

It also can be that the function is flipping between left-right-left-right- and so on (or up-down-up-down), and causing a stack overflow...

Or maybe you should think about another way to delete the blocks...

[JPulham]

fixed...

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if the block is empty don't bother

I could debug it I just wondered if you could fix it before my friend went home... but it works now.