Also, to make this AUCTeX-related, after setting LaTeX-command to
xelatex and typing C-c C-c in the test1.tex buffer, the compilation
failed with the uninformative message "LaTeX: problems after [0] pages"
and no log output. But running xelatex from the shell worked fine. Is
there something else necessary to use XeLaTeX in AUCTeX?
Have you checked the output of the TeX command with `C-c C-l` to see if there's
a more informative message? I've been using XeLaTeX for so long that I don't
remember if there's anything special I needed to configure. All I know is that
I have `TeX-engine` set to `xetex`.