Re: epic fsck SIGSEGV!

[Linus Torvalds <torvalds@linux-foundation.org>]

On Thu, 11 Dec 2008, Linus Torvalds wrote:
> 
> But obviously the true test for fsck is some complex corruption, and I 
> didn't test that. I can't imagine that it introduces any new problems 
> though - but the bugs you can't imagine are always the worst ones ;)

Btw, even if it doesn't introduce any bugs, it _does_ change the order 
that we traverse things in. It shouldn't matter, of course, but because it 
always picks the last entry from the object array (it really treats the 
array as a stack), it ends up traversing parents of commits (and the 
entries in trees) by looking at the last parent (or entry) first.

The whole two-phase thing also means that rather traverse the references 
as we find them, we'll end up traversing things later in one group. Again, 
access ordering will change.

Absolutely nothing should care about this from a correctness angle, of 
course, but I thought I'd point it out because I think it will change the 
order that we print out errors in.

So if somebody has some test-case, and you get different output 
before-and-after, it's not necessarily any indication of a problem, just 
an effect of doing object traversal in slightly different order.

		Linus