>>But, this raises a question: do panics in the kernel, with DIAGNOSTIC
>>turned on, still signal a potential bug?  I'm thinking kind of
>>anologeous to warnings emitted from a C compiler.  In other words: in
>>a kernel where all known "warnings" were "fixed", should it be
>>expected that this kernel would never panic if DIAGNOSTIC was built
>>in?

>Mostly; unrecoverable errors would still cause a panic.

Right, but I'm getting panics with DIAGNOSTIC built in that don't
occur with it off.  Either someone is making a wrong assumption in
some diagnostic code, or there is a silent bug eating its way through
my (and maybe all of our) system(s).

>Code wrapped by #ifdef DIAGNOSTIC performs sanity checking of
>assumptions made by kernel code.  In your case, disabling DIAGNOSTIC
>may eliminate panics, but at the cost of possibly introducing silent
>filesystem corruption.  I'd prefer a panic, myself.

Well, I'd prefer to not have my system hang every couple of days.  I'd
prefer a panic iff the bug could be diagnosed and fixed quickly
afterwards.  Unfortunately, my mail went completely unanswered, and I
don't have the expertise to fix it.  Maybe I'll resubmit my mail as a
PR, but I don't know that I have enough info to make it a useful PR.

Anyway, I'd also prefer it not to panic if this is an incorrect
assumption in the diagnostic code.

But the gist of this is you confirming what I thought.  That, with a
system known to be free of all "known" "bugs", enabling DIAGNOSTIC
should not cause any panics.  (This an in theory, not necessarily in
practice, kind of thing.)

-----------------------------------------------------------------------------
  Michael L. VanLoon                                 michaelv@HeadCandy.com
        --<  Free your mind and your machine -- NetBSD free un*x  >--
    NetBSD working ports: 386+PC, Mac 68k, Amiga, Atari 68k, HP300, Sun3,
        Sun4/4c/4m, DEC MIPS, DEC Alpha, PC532, VAX, MVME68k, arm32...
    NetBSD ports in progress: PICA, others...

   Roll your own Internet access -- Seattle People's Internet cooperative.
                  If you're in the Seattle area, ask me how.
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