What causes a Stack Overflow Error?

Author

Message

gearce

18

Years of Service

User Offline

Joined: 18th Dec 2006

Location: ex SCOTLAND, now MELBOURNE, Australia

Posted: 11th Apr 2008 10:27 Edited at: 11th Apr 2008 10:50

Link

Hi there!

What causes a Stack Overflow Error.

I have a puzzle programme where it works once ...... maybe twice or thrice then I get a message:

Runtime error at line 668. Stack Overflow Error.

The lines in question in my programme are

665 rem Until mouse is clicked
666 do
667 mx=mousex():my=mousey():mc=mouseclick()
668 if mc=1 then gosub checkregion:return
669 loop

Is this enough information to work on? I don't want to reveal too much as my programme is a work in progress.

Any help would be much appreciated.

============ EDIT ============

OK. Found something from a previous post

Quote: "Posted: 27th Apr 2004 00:17

I think it is the way your program runs. It is bad to goto a sub then goto another sub from in that sub. It keeps pilling stuff on the stack."

but I would be interested to hear from others.

Thanks!

gearce
(GRC)

LANG MEY YER LUM REEK

My mother's menu consisted of two choices: take it or leave it.

Back to top

Profile PM

LBFN

18

Years of Service

User Offline

Joined: 7th Apr 2007

Location: USA

Posted: 11th Apr 2008 12:53

Link

If your 'checkregion' subroutine calls the above listed rotuine, you will overflow the stack. Make sure that they do not call one another. You could code it slightly differently:

+ Code Snippet

665 rem Until mouse is clicked
666 repeat
667   mx = mousex() : my = mousey() : mc = mouseclick()
668 until mc = 1
669 return

LBFN

Back to top

Profile PM Email

Bluestar4

19

Years of Service

User Offline

Joined: 19th Dec 2005

Location: USA

Posted: 12th Apr 2008 08:49

Link

Interesting......I've never encountered a stack overflow error in DBC.
1. I suggest that you copy your sub routine(s) into the main part of the program and place breaks at every other line until you find the exact portion of your code where it crashes.
in view that dbc doesn't have trace debugging I think you will find that this will be the best solution to find exactly where the bug is -
2. REcursion - CAREfully check your program for recurssion ! whether its a function or a sub , make sure that your program at run time breaks out of each and every one and goes back to its proper place rather than repeatably using resources !

Sutter Soft
http://www.geocities.com/suttersoft

Back to top

Profile PM Email

Hummanoid Typhoon

19

Years of Service

User Offline

Joined: 4th Aug 2005

Location: Middle of nowhere

Posted: 12th Apr 2008 16:02

Link

Does it get stuck within a never ending sub?

Never got one in DBC but in c# you get stack overflows if you perform lots of sequential operations within the main forms thread without letting it refresh.