Re: apr_hash_overlay returns hash with duplicate keys

On 10 December 2015 at 19:14, Julian Foad <julianfoad_at_apache.org> wrote:
> APR devs, Subversion devs:
>
> On Subversion's Mac OS buildbots it appears that apr_hash_overlay()
> sometimes returns a hash containing duplicate keys, which (as I
> understand it) should be impossible.
>
> We had an issue where some 'svnmover' tests were failing only on Mac
> OS buildbots. I added some debugging in Subversion commits r1719056,
> r1719067, r1719072, r1719074.
>
> Buildbot result:
> https://ci.apache.org/builders/svn-x64-macosx-bdb/builds/485/steps/Test%20ra_svn%2Bbdb
> --> debug output in 'faillog' shows duplicate keys in hash:
> "union_children={A, iota, foo, boozle, boozle, iota}"
>
> I replaced apr_hash_overlay() with my own simple re-implementation:
>
> http://svn.apache.org/r1719089 -- re-implement hash overlay
>
Hi Julian,

That could be possible if two hashes uses different hash functions.
This could happen if you're using svn_hash__make() directly or
indirectly: for example RA get_dirent for svn:// protocol returns hash
with non-standard hash-function.

-- 
Ivan Zhakov