I wrote:
> A suggestion is to run the pg_upgrade with -r switch, which will leave a
> litter of files in your working directory. Some of them will be named
> like pg_upgrade_dump_NNN.custom and should be custom-format, schema-only
> dumps of your 9.4 installation's databases. If you'd be willing to send
> those to me off-list, maybe I could figure out what's happening.
> It occurs to me that this might actually be related to the issue you
> saw in "dump" mode --- if there's some unresolved circular dependency,
> it could cause pg_dump to dump things in an unexpected order, which
> could possibly explain the message we're seeing. But that's just a
> guess.
BTW, there will also be .log files, which might contain useful information
as well, especially if any of it is bleats from pg_dump about being unable
to break a circular dependency.
regards, tom lane