This utility is intended to be used by $(TOP)/configure to check sphinx's python version. We need python3-sphinx instead of python2-sphinx to build documentation, such as GHC user's guide. However, it can't be confirmed with the command line option of sphinx-build. This utility performs a version check via conf.py invoked from sphinx-build. Usage: $SPHINXBUILD -b text . dist > /dev/null 2>&1 echo $? If your python for sphinx is python2, it returns error status code 1. See description in $(TOP)/configure.ac.