Comment # 5 on bug 948165 from Bernhard Wiedemann

I can reproduce it on my factory (on ext4) install with latest
glibc-2.22-3.1
coreutils-8.24-2.3.x86_64

using
LC_COLLATE=cs_CZ.UTF-8 /usr/bin/ls -1 /etc/pam.d/

though the result is slightly differently (and consistently so) wrong:

common-account
common-account.pam-config-backup
common-auth
common-auth.pam-config-backup
common-auth-pc
common-password
common-password.pam-config-backup
common-password-pc
common-session
common-session.pam-config-backup
common-session-pc
crond
cups
groupadd
groupdel
groupmod
chsh
common-account-pc
init
...

here is an even nicer reproducer:
cd /etc/pam.d/
diff -u <(LC_COLLATE=cs_CZ.UTF-8 /usr/bin/ls -1)\
 <(/usr/bin/ls -1|LC_COLLATE=cs_CZ.UTF-8 sort)

but why is that different from
diff -u <(LC_COLLATE=cs_CZ.UTF-8 /usr/bin/ls -1)\
 <(LC_COLLATE=cs_CZ.UTF-8 /usr/bin/ls -1|LC_COLLATE=cs_CZ.UTF-8 sort)

That could indicate, that the comparison function finds equality
and thus the unstable quick-sort algorithm is not caring about order


when adding files named
chsx123456789
chsx1234567890
those were also mis-sorted, making a total of 4
but when adding another
chsx123456789012
only that one and the one before were mis-sorted.
And is "sort" really using the same strcoll function?

Interestingly, when I do cp -a /etc/pam.d . (on the same partition)
the effect remains active on the copy, even when I use tar.
But when copying to /home/ the effect is not there.