Don't call methods on NULL pointers when built with a modern compiler.
MarkC just reported that condor_annex status segfaults on submit4.chtc.wisc.edu.
I investigated, and condor_annex -status also fails. They both also failed on submit3.chtc.wisc.edu, which has a debbuger; the problem is that the status commands are looking up an attribute in a NULL ClassAd pointer.
This used to “work” because an accident of construction: the method in question would exit a loop early if this were NULL. However, newer compilers “know” that this is never NULL and skip the check (at least the first time through the loop).
To explain last three commits: the code was initially pushed to the 8.8 branch for 8.8.14 and then cherry-picked into the 8.8.13 branch; the release note was copied to 8.8.13 branch but moved to the appropriate section; and the original release note was reverted out of the 8.8 branch to avoid duplication.
Code looks good.