doc build full of warnings and errors, sphinx-build exits with success
part of admin/build-doc:
$ build-doc/virtualenv/bin/sphinx-build -a -n -b dirhtml -d doctrees doc build-doc/output/html
. . .
build succeeded, 315 warnings.
$ echo $?
Adding -W makes the first warning exit, but why do the ERRORs currently present not at least make sphinx-build exit with an error, and what do we do about it?
See attachment for how broken it all is