Re: assert vs. abort

[Ben Pfaff]

John Darrington <address@hidden> writes:

> On Sat, Apr 01, 2006 at 11:16:42AM -0800, Ben Pfaff wrote:
>      
>      >      How about this:
>      >      
>      >          ASSERT() -- for cheap, important checks
>      >          ASSERT1() -- for more expensive or less important checks
>      >          ASSERT2() -- for expensive checks
>      >          ASSERT_LEVEL -- if defined to a number, checks at the given
>      >          level or higher are disabled.
>      >          NOT_REACHED() -- as discussed

> Doesn't this still leave a problem if we want to add a level between 1
> & 2 ?  

I am confused why we would want to do that.  I wouldn't think
we'd want more than a couple of levels.

However--I haven't had much experience with multiple levels of
assertions.  Have you?  If you do, then perhaps your experience
can guide our choices.

> I would perform the following sedscript on the above.
> s/ASSERT1/ASSERT_EXPENSIVE/ s/ASSERT2/ASSERT_VERY_EXPENSIVE/
> s/\ 1/\ 10/ s/\ 2/\ 20/

My main objection is that something like ASSERT_VERY_EXPENSIVE is
too long.  Is there a shorter way to express the same intent?

>      > * NOT_REACHED should *always* be enabled.
>      
>      ...though I'd argue that it should just expand to abort() when
>      all assertions are otherwise disabled.
>
> I'd have to respectfully disagree.  Our "You have discovered a
> bug...." message has brought a number of bug reports which I believe
> would otherwise have gone unreported.  Many people won't take the
> effort to report a bug if the program just terminates with the rather
> concise message "Aborted".

You may be right.

However, I only meant to suggest that NOT_REACHED() should just
expand to abort() when *all* assertions were disabled, i.e. at
ASSERT_LEVEL 0.

-- 
"Ho ho ho. I _so_ enjoy making a fool out of myself."
--Linus, on Christmas Day, 2000