Simple tests to check all probe aliases

[Mike Mason]

Frank Ch. Eigler wrote:
> Mike Mason <mmlnx@us.ibm.com> writes:
> 
>> [...]
>>   probe nfs.*.*, nfs.*.*.* {}
>> This simple script exposed 24 unresolvable probe aliases.
> 
> Indeed, this is a class of genuine bugs.
> 
>> [...] I know there's been disagreement as to the value of using -u,
>> that it would report $var problems that we already know about and
>> can do little to fix.  
> 
> Not just that -- a user cannot accidentally refer to $vars like she
> can to probes (there is no equivalent of "probe * {}" like "$*"), so
> this class is much less interesting.

Hmm... maybe I'm not being clear.  Wildcarding target variables isn't
something I even considered.  I just think we should do our best to 
make sure the arguments in the tapset probes are actually accessible.
The only way I know to do that is test them all and, when we find
problems, fix those we can.

> 
>> I still think too much test data is better than too little.  We can
>> use the kfail mechnaism if it becomes too annoying.
> 
> It will become instantly annoying.  If you like, check in two copies
> of the tests, once with -u (and you might as well instantly mark it
> kfail), and once without (which should pass).

-u exposes both fixable and unfixable target variable problems.
I don't think we should ignore problems we can fix because we might 
expose some we can't.

I'm not trying to be difficult.  I just want to help make SystemTap
better for the users.  I think it's reasonable for users to expect
the advertised probe arguments (those documented in the man pages) 
to be available for use.

Mike

> 
> 
> - FChE