-used not working correctly?

[Martin Schulte]

Hello,

I create files t<n> (n=1,3,5,7) with ctime=now and atime=now+<n> days:

$ uname -a
$ echo
$ find --version
$ for d in 1 3 5 7; do
>   touch -a -d "$(date -d "$d day" '+%Y-%m-%d %H:%M:%S')" t$d
> done
$ echo
$ echo find:
$ find . -name 't?' -used +4
$ echo done.

I expect
./t5
./t7
as output from find but I get nothing:

Linux martnix4 4.9.0-11-amd64 #1 SMP Debian 4.9.189-3+deb9u1 (2019-09-20)
x86_64 GNU/Linux

find (GNU findutils) 4.7.0-git
Copyright (C) 2016 Free Software Foundation, Inc.
License GPLv3+: GNU GPL version 3 or later
<http://gnu.org/licenses/gpl.html>. This is free software: you are free
to change and redistribute it. There is NO WARRANTY, to the extent
permitted by law.

Written by Eric B. Decker, James Youngman, and Kevin Dalley.
Features enabled: D_TYPE O_NOFOLLOW(enabled) LEAF_OPTIMISATION FTS
(FTS_CWDFD) CBO(level=2) 

find:
done.

Do I misunderstand the man page? If this is a bug, it looks as if
pred_used calls pred_timewindow with a bad second argument (absolute time
iso relative to ctime).

Best regards,

Martin