Hi Michal, Em Thu, 6 May 2021 19:48:49 +0200 Michal Suchánek <msuchanek@xxxxxxx> escreveu: > [ 127s] + : > [ 127s] + locale > [ 128s] LANG=en_US > [ 128s] LC_CTYPE="en_US" > [ 128s] LC_NUMERIC="en_US" > [ 128s] LC_TIME="en_US" > [ 128s] LC_COLLATE="en_US" > [ 128s] LC_MONETARY="en_US" > [ 128s] LC_MESSAGES="en_US" > [ 128s] LC_PAPER="en_US" > [ 128s] LC_NAME="en_US" > [ 128s] LC_ADDRESS="en_US" > [ 128s] LC_TELEPHONE="en_US" > [ 128s] LC_MEASUREMENT="en_US" > [ 128s] LC_IDENTIFICATION="en_US" > [ 128s] LC_ALL= > [ 128s] + echo LC_ALL= > [ 128s] LC_ALL= > [ 128s] + echo LANG=en_US > [ 128s] LANG=en_US Where those the locale settings that you used when the build failed? I tried to reproduce the bug here with, disabling the parallel run (as it masks the real error) with both: $ for i in LANG LC_ALL LC_ADDRESS LC_IDENTIFICATION LC_MEASUREMENT LC_MONETARY LC_NAME LC_NUMERIC LC_PAPER LC_TELEPHONE LC_TIME; do echo $i=en_US; done $ make cleandocs && make SPHINXOPTS=-j1 htmldocs (this one caused lots of warnings on Debian, due to the settings at /etc/locale.gen) and: $ for i in LANG LC_ALL LC_ADDRESS LC_IDENTIFICATION LC_MEASUREMENT LC_MONETARY LC_NAME LC_NUMERIC LC_PAPER LC_TELEPHONE LC_TIME; do echo $i=en_US.ISO-8859-1; done $ make cleandocs && make SPHINXOPTS=-j1 htmldocs Without any success. Could you please provide more details about the build VM and the git changeset that caused the issue? Thanks, Mauro