A compiler warning would be nice if the linker does not accept the
option. Otherwise, the compiler should not advertise it accepts the
option. Accepting it without warning has wasted hours of build time in
this emulated environment. (-fsanitize=address produces a warning, and
we skip the configuration during testing).

...
g++ -DDEBUG -g2 -O1 -std=c++03  -pipe -fsanitize=undefined -c fipsalgt.cpp
g++ -DDEBUG -g2 -O1 -std=c++03  -pipe -fsanitize=undefined -c dlltest.cpp
g++ -o cryptest.exe -DDEBUG -g2 -O1 -std=c++03  -pipe
-fsanitize=undefined bench.o bench2.o test.o validat1.o validat2.o
validat3.o adhoc.o datatest.o regtest.o fipsalgt.o dlltest.o
./libcryptopp.a -pthread
/usr/bin/ld: cannot find -lubsan
collect2: error: ld returned 1 exit status
GNUmakefile:367: recipe for target 'cryptest.exe' failed

**********

# uname -a
Linux core2 3.16.0-4-amd64 #1 SMP Debian 3.16.7-ckt11-1+deb8u5
(2015-10-09) aarch64 GNU/Linux

debian-arm64:/# g++ --version
g++ (Debian/Linaro 4.9.2-10) 4.9.2
Copyright (C) 2014 Free Software Foundation, Inc.
This is free software; see the source for copying conditions.  There is NO
warranty; not even for MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.

**********

# apt-cache show g++
Package: g++
Source: gcc-defaults (1.136)
Version: 4:4.9.2-2
Installed-Size: 34
Maintainer: Debian GCC Maintainers <debian-gcc@lists.debian.org>
Architecture: arm64
Provides: c++-compiler
Depends: cpp (>= 4:4.9.2-2), gcc (>= 4:4.9.2-2), g++-4.9 (>=
4.6.4-1~), gcc-4.9 (>= 4.6.4-1~)
Description-en: GNU C++ compiler
 This is the GNU C++ compiler, a fairly portable optimizing compiler for C++.
 .
 This is a dependency package providing the default GNU C++ compiler.
Description-md5: 4d44b18774ae5123b7c3f70d940cf655
Build-Essential: yes
Tag: devel::compiler, devel::lang:c++, implemented-in::c,
 interface::commandline, role::dummy, role::metapackage, suite::gnu,
 works-with::software:source
Section: devel
Priority: optional
Filename: pool/main/g/gcc-defaults/g++_4.9.2-2_arm64.deb
Size: 1518
MD5sum: 6f12e1b386fb7056857365db6d8829d6
SHA1: e7e9581bdc59d2254e9a3636e0f7605da48d4270
SHA256: 28ec989b9e4e47ad25588fd2082ff5767767bb49ee37a30d184dd4a9bfa06a89

(Please ignore post #45 where my misconfigured mail transport totally messed up formatting - sorry for that)
I observe the same behaviour with systemd 228-2, like several people report at http://forum.siduction.org/index.php?topic=5901.0

Double checked that etc/systemd/system/getty.target.wants/getty@tty1.service as well as /lib/systemd/system/getty@.service both contain 'IgnoreOnIsolate=yes'

One user in above forum reported the same for Fedora since Fedora21, so not debian specific (some wild guesses were that its rather introduced by xserver setuid change than by systemd itself?).

Michael Singer reported in IRC that he had no problems on Nov 12 and observed the bug on Nov 15, probably systemd 227-2 -> 227-3

----

New test with several ttys, 3x root on tty1,tty2,tty3, user on tty4. On isolate-command, all of them get logged out.

## System running inside Virtualbox 5.0.8.10
linux-image-4.3.0-towo.3-siduction-686 4.3-2
systemd 228-1
plasma-desktop 4:5.4.2-1
kde-runtime 4:15.08.2-1
xserver-xorg-core 2:1.17.3-2

Before isolate command, root on tty1, user-session active:
#loginctl list-sessions
SESSION   UID USER  SEAT
c1     105 lightdm seat0
1    1000   myuser seat0
2      0    root  seat0
3 sessions listed

After isolate command, root on tty1 re-logged in:
#loginctl list-sessions
SESSION   UID USER  SEAT
3      0    root  seat0
1 sessions listed

Part of journal between the two root logins (before/after isolate command) added.