I wrote:
> ... or maybe not just yet. Andres' buildfarm critters seem to have
> a different opinion than my machine about what the output of
> collate.icu.utf8 ought to be. I wonder what the prevailing LANG
> setting is for them, and which ICU version they're using.
Oh, I bet it's "C.utf8", because I can reproduce the failure with that.
This crystallizes a nagging feeling I'd had that you were misdescribing
the collate.icu.utf8 test as not being run under --no-locale. Actually,
it's only skipped if the encoding isn't UTF8, not the same thing.
I think we need to remove the default-collation cases from that test too.
regards, tom lane