I'm not even sure this is worth asking, since it's such a vague yet complex problem. But here goes. My program recently started behaving... oddly. It compiles perfectly, but about 75% of the time running it immediately produces an error. It's not a run-time error, like I said it runs fine sometimes. And when my game loop is exited and the program prepares to close, I get a debug assertion failure every time.

The program is an Allegro ASCII library I'm programming, and the only guess I have is that Allegro is going crazy from all the images I'm blitting to the screen. But even that seems unlikely, the program hardly uses any CPU and even when I remove most of the draw commands from the loop I get the error just as often.

HEEEEEEELLLLLLP

Thanks in advance.

No warnings to speak of. My main .cpp probably wouldn't be of much help if I posted it, since most of it is just referencing functions in the library I'm building. That's almost certainly where the problem is coming from, but it's a mountain of code. Want to see it...?

I've run step-by-step through the program multiple times, it never encounters any kind of errors. It would help if I knew what the hell an assertion failure was.

On that note, I think you're overestimating my programming knowledge.

EDIT: I need to start specifying that I'm using Allegro 5. How would I use that nifty reality-breaking assert handler in 5.0?

Sorry, I don't believe that functionality is available in Allegro 5, but it should be.

An assertion failure is when a program fails an assert call.

#include <assert.h>// C
#include <cassert>// C++

assert(1);// fine, 1 evaluates to true, assertion passed
assert(0);// %!#$%, 0 evaluates to false, assertion failed, abort called

Are you on Windows? I think an error message pops up when assert is failed on Windows. Do you have any idea where the assertion failure is coming from?

Oh, that particular assertion is a CRT exception. It means that some memory function was attempted on a pointer that isn't a valid heap pointer pointing into your local heap. This usually means one of three things:

1) You attempted to use free(), realloc(), or delete on a pointer that isn't valid, for instance if you try to free() the same pointer twice. The pointer is invalid because it has already been freed.

2) You're freeing a pointer that was originally allocated in a DLL (as opposed to your main program), or vice versa. The pointer is invalid because DLLs you load have their own heap separate from your application's local heap.

3) You're mixing debug and release CRTs and allocating/freeing memory from different CRTs. The pointer is invalid because the debug and release CRTs have different internal allocation semantics.

EDIT: Nevermind, I see your error. You're using the wrong kind of delete. You allocated the tile array with new[], so you have to delete it with delete[].

Yes, that's right. By the way, you never free the pointers inside the array. Also make sure you're not making any accidental copies of that class anywhere (doing so is a sure way to crash -- your class does not have full copy semantics).

It's entirely plausible for there to be more errors like this around. Check around for suspicious deletes, and paste if you have more details for us.

I thought I needed to delete the "rows" of the array first, I was trying to think of a way to gauge the size of the array to make sure I got all of them. Then I remembered I had a perfectly good variable called window.w as part of the class that I made for exactly that purpose. SIGH

If you think my lack of indents here is bad, you should see the atrocious ocean of poorly-formatted code that constitutes that library I'm building. Speaking of which, part of that library is probably where the error is originating. Thanks for the help so far, I'll post more if I find anything suspicious.

But first: the bitmap called ascii is declared and defined in the object library but freed at the end of my main program by the EndAllegro function. Could that have to do with the assertion failure?

All that matters if whether they are part of the same heap or not. But you know, when that debug assertion is hit, you should be able to get a stack trace out of windows that will show you exactly what caused it. What compiler do you use?

Run your program from inside the IDE, with F5 (not Ctrl+F5). When the assertion hits, press "Retry".

Yes, now Break. You will get the debugging view in MSVC, which has all the goodies including a stack trace.

Well for one thing you're overrunning all your buffers:

if(x<=window.w && y<=window.h)

You're checking the wrong bounds again.

void Draw_Char(int code,Window window,int x,int y)

You're passing window by value, and not by reference. That means whatever you do to modify window will be done to a local copy and not to the Window you're passing to the function. It works in this case because the local copy of window has the same Tile** tile that the one passed to the function does.

I don't know why line 11 is failing though, sorry.