latexmk -xelatex 生成带有空白页而不是 unicode 字符的 texfile

Question

代码：

\documentclass[12pt]{article}
\begin{document}
ääßöüü
\end{document}

使用选项：latexmk -xelatex test.tex导致出现空白页。

这里有什么问题？

日志：

Latexmk: This is Latexmk, John Collins, 10 Nov 2013, version: 4.39.
**** Report bugs etc to John Collins <collins at phys.psu.edu>. ****
Latexmk: applying rule 'pdflatex'...
Rule 'pdflatex': Rules & subrules not known to be previously run:
   pdflatex
Rule 'pdflatex': The following rules & subrules became out-of-date:
      'pdflatex'
------------
Run number 1 of rule 'pdflatex'
------------
------------
Running 'xelatex  -recorder  "test.tex"'
------------
This is XeTeX, Version 3.14159265-2.6-0.99992 (TeX Live 2015/dev/Debian) (preloaded format=xelatex)
 restricted \write18 enabled.
entering extended mode
(./test.tex
LaTeX2e <2014/05/01>
Babel <3.9l> and hyphenation patterns for 79 languages loaded.
(/usr/share/texlive/texmf-dist/tex/latex/base/article.cls
Document Class: article 2014/09/29 v1.4h Standard LaTeX document class
(/usr/share/texlive/texmf-dist/tex/latex/base/size12.clo)) (./test.aux)
[1] (./test.aux) )
(see the transcript file for additional information)
Output written on test.pdf (1 page).
Transcript written on test.log.
Latexmk: Log file says output to 'test.pdf'
Latexmk: All targets (test.pdf) are up-to-date

Answer 1

我错过了\usepackage{fontspec}。我确实理解 XeTeX，因为它有内置的 unicode 支持。抱歉。