[tex-live] reproducible builds with xetex/xdvipdfmx: /CMapName contains path.

[Ulrike Fischer]

If I compile the following with xelatex --no-pdf and xdvidfpmx -z0 I
get an absolute path in the pdf:

/CMapName
/d:-texlive-2018-texmf-dist-fonts-opentype-public-lm-lmroman10-regular.otf,000-UTF16
def

Is there a way to avoid this? It makes reproducible pdf testing with
xelatex impossible. 

\documentclass{article}

\begin{document}
\font\test=["lmroman10-regular.otf"] \test abc
\end{document}

(setting SOURCE_DATE_EPOCH and FORCE_SOURCE_DATE doesn't change the
output).

-- 
Ulrike Fischer 
http://www.troubleshooting-tex.de/