Problem with polyglossia and MinionPro

I have a problem with small caps not showing correctly when loading polyglossia. I am trying to use polyglossia with classicthesis, which I know is unsupported, but the same problem appears when loading MinionPro, polyglossia and using small caps. MWE:

  \documentclass{scrbook}
\usepackage{polyglossia}
\usepackage{classicthesis}
\begin{document}
\chapter{Foo}
\section{Bar}
\subsection{Baz}
\end{document}


Here Bar is not set in small caps. MWE2:

  \documentclass{scrbook}
\usepackage{polyglossia}
\usepackage{MinionPro}
\begin{document}
\textsc{Should be small caps}
\end{document}


Now I do get font substitution warnings but these don't make sense. Why would polyglossia change the font encoding and is there a way to stop it?

• If I use \setmainfont{Minion Pro} instead of \usepackage{MinionPro} (that I don't have), small caps are typeset correctly. – egreg Oct 29 '13 at 9:02
• In the minimal sample this works for me too, but I get a different font and getting this to work with my actual document does not seem to work – Max Oct 29 '13 at 9:03
• polyglossia loads fontspec (which is recommended if you use lualatex). Fontspec changes the font encoding to an encoding suitable for an unicode engine like lualatex but this clashes with minionpro.sty (which is meant for pdflatex). If you want to switch to lualatex you will have to change your font setup - and you should load polyglossia after packages which perhaps revert to a pdflatex setup. – Ulrike Fischer Oct 29 '13 at 9:26

polyglossia loads fontspec (which is recommended if you use lualatex). fontspec changes the font encoding to an encoding suitable for an unicode engine like lualatex but this clashes with minionpro.sty (which is meant for pdflatex).

If you want to switch to lualatex you will have to change your font setup - and you should always load polyglossia after packages which perhaps reverts to a pdflatex setup.