[yocto] PetaLinux build fails because of locale errors logged by do_rootfs (Ubuntu 18.04 LTS)

[Tőkés Attila]

Hi Yocto Team,

First of all sorry for spamming your mailing list, but I'm kind of out ideas with this...

I'm trying to build PetaLinux on Ubuntu 18.04 LTS, but the build is failing because of some (probably harmless) locale related errors the do_rootfs subtask logs:

bluetiger at Attila-Laptop:xilinx-ultra96-reva-2018.2$ petalinux-build[INFO] building project
[INFO] sourcing bitbake
INFO: bitbake petalinux-user-image
WARNING: Host distribution "ubuntu-18.04" has not been validated with this version of the build system; you may possibly experience unexpected failures. It is recommended that you use a tested distribution.
...
WARNING: petalinux-user-image-1.0-r0 do_rootfs: [log_check] petalinux-user-image: found 1 warning message in the logfile:
[log_check] warning: %post(sysvinit-inittab-2.88dsf-r10.ultra96_zynqmp) scriptlet failed, exit status 1

ERROR: petalinux-user-image-1.0-r0 do_rootfs: [log_check] petalinux-user-image: found 4 error messages in the logfile:
[log_check] Failed to set locale, defaulting to C
[log_check] Failed to set locale, defaulting to C
[log_check] Failed to set locale, defaulting to C
[log_check] Failed to set locale, defaulting to C


ERROR: petalinux-user-image-1.0-r0 do_rootfs: Function failed: do_rootfs
ERROR: Logfile of failure stored in: /media/bluetiger/Data/PetaLinux-Ultra96/xilinx-ultra96-reva-2018.2/build/tmp/work/ultra96_zynqmp-xilinx-linux/petalinux-user-image/1.0-r0/temp/log.do_rootfs.5592
ERROR: Task (/media/bluetiger/Data/PetaLinux-Ultra96/xilinx-ultra96-reva-2018.2/project-spec/meta-plnx-generated/recipes-core/images/petalinux-user-image.bb:do_rootfs) failed with exit code '1'
NOTE: Tasks Summary: Attempted 10052 tasks of which 10051 didn't need to be rerun and 1 failed.

Summary: 1 task failed:
/media/bluetiger/Data/PetaLinux-Ultra96/xilinx-ultra96-reva-2018.2/project-spec/meta-plnx-generated/recipes-core/images/petalinux-user-image.bb:do_rootfs
Summary: There were 2 WARNING messages shown.

Summary: There were 2 ERROR messages shown, returning a non-zero exit code.
The locales seems to be just fine on the machine:

bluetiger at Attila-Laptop:~$ localeLANG=en_US.UTF-8
LANGUAGE=en_US.UTF-8
LC_CTYPE="en_US.UTF-8"
LC_NUMERIC="en_US.UTF-8"
LC_TIME="en_US.UTF-8"
LC_COLLATE="en_US.UTF-8"
LC_MONETARY="en_US.UTF-8"
LC_MESSAGES="en_US.UTF-8"
LC_PAPER="en_US.UTF-8"
LC_NAME="en_US.UTF-8"
LC_ADDRESS="en_US.UTF-8"
LC_TELEPHONE="en_US.UTF-8"
LC_MEASUREMENT="en_US.UTF-8"
LC_IDENTIFICATION="en_US.UTF-8"
LC_ALL=en_US.UTF-8


Does anyone know what causes the problem? Is there a way to fix / workaround it?
Yesterday, I had a similar problem with bitbake's sanity checks, but I solved that by commenting out some code in sanity_check_locale() from sanity.bbclass.

Is this something Ubuntu 18.04 related? If I understood correctly Ubuntu 18.04 is not officially supported. But maybe it would worth checking what causes this error.

I would really appreciate any help on this...

Thanks,
Attila