Re: Listing probe alias resolution failures

[fche at redhat dot com (Frank Ch. Eigler)]

David Smith <dsmith@redhat.com> writes:

> > $ stap -p2 -u -e 'probe vm.mmap ? { }'
> > semantic error: failed to retrieve location attribute for local
> > 'addr' (dieoffset: 0xb84881): identifier '$addr' at
> 
> [...]
> # stap -p2 -e 'probe vm.mmap ? { printf("%p %d\n", address, length) }'
> semantic error: failed to retrieve location attribute for local 'addr'
> (dieoffset: 0xbf6524): identifier '$addr' at
> /usr/local/share/systemtap/tapset/memory.stp:118:15

Indeed, this is probably an instance of PR 1155, and one of the
reasons for the optimization pass in the first place.  It's partly

> Here it seems like we should be able to discard the probe before
> trying to look up its parameters.  Could you file a bugzilla on this
> so we don't forget to look at this?

Specifically, are you suggesting that

   probe kernel.function("something_that_exists") ? { 
      f($non_existent_variable) 
   }

should be accepted?

- FChE