Re: Have you ever had a bug caused by...

[mjsilva697@earthlink.net (Mike Silva)]

Dr Adrian Wrigley <amtw@linuxchip.demon.co.uk> wrote in message news:<3BD1CA15.6492D999@linuxchip.demon.co.uk>...
> Mike Silva wrote:
> > Have you ever had a bug caused by accessing off the end of an array?
> >...
> > Have you ever had a bug caused by a variable getting set to a value
> > outside its designed range?
> 
> These are occasionally the *cause* of a bug.  But more often they
> are the *effect* of a bug. (Maybe it's just semantics, but I
> think of some items on the list as the result of bugs, not the cause)
> 
> In C, execution problems can arise due to a bug, and things collapse
> much later, leading to much confusion and wasted time.
> 
> In Ada, execution usually fails much earlier because of range checking,
> leading the programmer to focus on the relevant part of the code.
> This proximity of cause and effect is a big help debugging Ada.

I agree that some of the list items are the result, not the cause, of
a bug; but as you say, Ada will help by screaming bloody murder much
more quickly.  I was taking some liberties with the language -- maybe
somebody can think of a more accurate but still snappy formulation.

Mike