Warnings when using babel with LuaLaTeX

You can use this to suppress the warnings:

\documentclass[12pt,a4paper]{report}
\usepackage{fontspec}
\def\magyarOptions{suggestions=no}
\usepackage[magyar,english]{babel}

\begin{document}
This is such a nice document.
\end{document}

magyar.ldf is quite long and contains lots of adaptions and patches (often optional). It obviously hasn't been adapted to lualatex/xelatex yet. The fontencoding seems to be ok with this engines but there is no garanty that there isn't somewhere code which implicitly assumes an 8-bit engine. So check the output.

These warnings emitted by magyar.ldf are harmless if lualatex and fontspec.sty are used. Until magyar.ldf becomes smarter about omitting these warnings, you can use uni8.sty, which loads t1enc.sty, fontenc.sty, inputenc.sty, luainputenc.sty, fontspec.sty, babel.sty and hyphenation patterns correctly (and suppresses useless warnings emitted by magyar.ldf). Example:

\documentclass[12pt,a4paper]{report}
\PassOptionsToPackage{english,magyar}{babel}
\usepackage[fontspec]{uni8}
\begin{document}
This is such a nice document.
\end{document}

Unfortunately, loading the packages above correctly (so that characters and hyphenation are both correct) with lualatex is quite tricky if fontspec.sty is not used. uni8.sty does that correctly as well.