PDF GENERATION PROBABLY FAILED.

Here's several lines of context for each line that appears to have an error:

Note that the real issue is often at the end of the last line of real data *before* the problem line; you should check there first.

Line 25, +/- 5:

    \setsansfont[Mapping=tex-text]{Linux Biolinum O}
    
    \usepackage{xeCJK}
    \setCJKmainfont{IPAexMincho}
    \setCJKsansfont{IPAexGothic}
    \setCJKmonofont{IPAGothic}
^^^ 
    \fancyhead{}          % empty out the header
    \fancyfoot{}          % empty out the footer
    \fancyhead[LE,LO]{\rightmark} % left side, odd and even pages
    \fancyhead[RE,RO]{\leftmark}  % right side, odd and even pages
    \fancyfoot[LE,RO]{\thepage}   % left side even, right side odd

Here's the end of the output from the PDF generation; this can be helpful in spotting errors. You can see the complete output by viewing the source of this page and searching for "with output:".

(/usr/share/texlive/texmf-dist/tex/xelatex/xltxtra/xltxtra.sty
(/usr/share/texlive/texmf-dist/tex/generic/iftex/ifluatex.sty
(/usr/share/texlive/texmf-dist/tex/generic/iftex/iftex.sty))
(/usr/share/texlive/texmf-dist/tex/generic/iftex/ifxetex.sty)
(/usr/share/texlive/texmf-dist/tex/latex/realscripts/realscripts.sty)
(/usr/share/texlive/texmf-dist/tex/latex/metalogo/metalogo.sty))
(/usr/share/texlive/texmf-dist/tex/xelatex/xecjk/xeCJK.sty
(/usr/share/texlive/texmf-dist/tex/latex/l3packages/l3keys2e/l3keys2e.sty)
(/usr/share/texlive/texmf-dist/tex/latex/l3packages/xtemplate/xtemplate.sty)
(/usr/share/texlive/texmf-dist/tex/xelatex/xecjk/xeCJK.cfg))
kpathsea: Running mktextfm IPAexMincho/OT
/usr/share/texlive/texmf-dist/web2c/mktexnam: Could not map source abbreviation  for OT.
/usr/share/texlive/texmf-dist/web2c/mktexnam: Need to update ?
mktextfm: Running mf-nowin -progname=mf \mode:=ljfour; mag:=1; ; nonstopmode; input OT
This is METAFONT, Version 2.7182818 (TeX Live 2020) (preloaded base=mf)

kpathsea: Running mktexmf OT

! I can't find file `OT'.
<*> \mode:=ljfour; mag:=1; ; nonstopmode; input OT
                                                  
Please type another input file name
! Emergency stop.
<*> \mode:=ljfour; mag:=1; ; nonstopmode; input OT
                                                  
Transcript written on mfput.log.
grep: OT.log: No such file or directory
mktextfm: `mf-nowin -progname=mf \mode:=ljfour; mag:=1; ; nonstopmode; input OT' failed to make OT.tfm.
kpathsea: Appending font creation commands to missfont.log.


! Package fontspec Error: The font "IPAexMincho" cannot be found.

For immediate help type H .
 ...                                              
                                                  
l.25 \setCJKsansfont
                    {IPAexGothic}
No pages of output.
Transcript written on _N_jpX0EXm.log.