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From: Alfred Perlstein <bright@mu.org>
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To: Navdeep Parhar <np@FreeBSD.org>
Subject: Re: svn commit: r244112 - head/sys/kern
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Cc: Adrian Chadd <adrian@FreeBSD.org>, src-committers@FreeBSD.org,
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On 12/12/12 4:02 PM, Navdeep Parhar wrote:
> On 12/12/12 14:48, Alfred Perlstein wrote:
>> On 12/12/12 2:29 PM, Andriy Gapon wrote:
>>> Now we get a new middle-ground: get both worse performance (because
>>> KASSERTs are compiled in) and a risk of harming your data (because
>>> KASSERTs no longer panic). The upside: there is no panic! There's just
>>> a log message (or etc). and chance to get more log messages because
>>> the insanity propagates. And a chance to lose your data (your
>>> customer's) - but I've already mentioned this. I am not sure that I
>>> like this kind of middle-ground.
>> I have a number of points here:
>>
>> The most important one being:
>> 1) without kassert you would still have the bug, just that it would be
>> unreported.
>>    The upside: there is no panic! There's **NO** log message (or etc).
>> and chance to get more log messages because the insanity propagates.
>>
>> Terrible!
>>
>> Let me explain that again:
>> If you don't compile in KASSERT, then it's not like the condition is
>> never going to happen.  Instead it will just be unreported.
> A KASSERT() really is for a condition that should never happen.  It is
> primarily useful during development and testing (and when the code is
> reworked or redesigned).  I agree with Andriy here -- a non-fatal assert
> shouldn't really exist.


What do you think happens to a FreeBSD kernel when INVARIANTS is 
compiled in and it trips an assertion after my change?


-Alfred