[Pkg-libvirt-maintainers] Bug#983944: libguestfs: ftbfs with -march=x86-64-v3

[Matthias Klose]

Package: src:libguestfs
Version: 1:1.44.0-2
Severity: minor
User: debian-gcc at lists.debian.org
Usertags: ftbfs-x86-64-v3

Starting with LLVM 12 and GCC 11 (and backported to gcc-10 for Debian), 
GCC introduces optimizations for new micro-architecture levels from
the x86-64 psABI.  Filing these bug reports for packages building with
the current level (x86-64), but not with x86-64-v3.

To reproduce these issues, append -march=x86-64-v3 to the compiler
flags (CFLAGS, CXXFLAGS, ...).  You also need hardware supporting these.
The easiest way is to call the dynamic linker in glibc 2.33 like
  /lib/x86_64-linux-gnu/ld-linux-x86-64.so.2 --help
Otherwise look at the flags in /proc/cpuinfo and compare these with
those from table 3.1 in the System V Application Binary Interface doc:
https://gitlab.com/x86-psABIs/x86-64-ABI/-/wikis/x86-64-psABI

Please don't upload a package setting these flags by default.  The
x86-64 baseline is still unchanged.

The full build log can be found at:
http://people.debian.org/~doko/logs/20210228/filtered/gcc10-v3/libguestfs_1.44.0-2_unstable_gcc10-v3.log
The last lines of the build log are at the end of this report.

[...]
clocksource: + cat /sys/devices/system/clocksource/clocksource0/current_clocksource

tsc

+ echo -n 'uptime: '

uptime: + cat /proc/uptime

7.63 0.94

+ cmd=guestfsd

++ grep -Eo 'guestfs_channel=[^[:space:]]+' /proc/cmdline

+ eval

+ test x '!=' x

+ test 1 = 1

+ cmd='guestfsd --verbose'

+ test '' = 1

+ false

+ test '' = 1

+ echo guestfsd --verbose

guestfsd --verbose

+ guestfsd --verbose

[    7.954228] traps: guestfsd[153] trap invalid opcode ip:7fa728c12e8e sp:7ffc92d50720 error:0 in libstdc++.so.6.0.28[7fa728bcf000+de000]

/init: line 257:   153 Illegal instruction     $cmd

+ sync

+ test '' = 1

+ reboot -f

Rebooting.

[    8.040504] sd 2:0:1:0: [sdb] Synchronizing SCSI cache

[    8.041017] sd 2:0:0:0: [sda] Synchronizing SCSI cache

[    8.042152] reboot: Restarting system

[    8.042296] reboot: machine restart

libguestfs: error: appliance closed the connection unexpectedly, see earlier error messages
libguestfs: child_cleanup: 0x563f6cfebc50: child process died
libguestfs: sending SIGTERM to process 9433
libguestfs: qemu maxrss 435260K
libguestfs: error: guestfs_launch failed, see earlier error messages
libguestfs: closing guestfs handle 0x563f6cfebc50 (state 0)
libguestfs: command: run: rm
libguestfs: command: run: \ -rf /<<PKGBUILDDIR>>/debian/build-4/tmp/libguestfsH4IV6N
libguestfs: command: run: rm
libguestfs: command: run: \ -rf /tmp/libguestfsxxdfeL
make[2]: *** [Makefile:3192: quickcheck] Error 1
make[2]: Leaving directory '/<<PKGBUILDDIR>>/debian/build-4'
make[1]: *** [debian/rules:130: override_dh_auto_test] Error 2
make[1]: Leaving directory '/<<PKGBUILDDIR>>'
make: *** [debian/rules:174: build] Error 2
dpkg-buildpackage: error: debian/rules build subprocess returned exit status 2