no answer needed, I'm adding the question as reference
After todays update of luaotfload microtype
gives an error when used with lualatex:
\documentclass{article}
\usepackage{microtype}
\begin{document}
abc
\end{document}
leads to
/tex/latex/microtype/microtype.lua:145: attempt to call field 'warning' (a nil v
alue)
stack traceback:
...exlive/2018/texmf-dist/tex/latex/microtype/microtype.lua:145: in main chunk
[C]: in function 'require'
[\directlua]:1: in main chunk.
l.59 \MT@lua{require("microtype")}