Build log attached. Am building from the most recent upstream commit
to core-updates (eff2e20688). bug#65479 "Docbook & XML/SGML
improvements" was merged to core-updates on October 10.

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Making all in documentation
make[2]: Entering directory
'/tmp/guix-build-docbook2x-0.8.8.drv-0/docbook2X-0.8.8/xslt/documentation'
../../perl/db2x_xsltproc -C ../../xslt/catalog.xml -s ./ss-texi.xsl -o
docbook2man-xslt.txml docbook2man-xslt.xml \
        -g output-file="docbook2man-xslt"
docbook2man-xslt.xml:1: parser error : Document is empty

^
unable to parse docbook2man-xslt.xml
make[2]: *** [Makefile:808: docbook2man-xslt.txml] Error 6
make[2]: Leaving directory
'/tmp/guix-build-docbook2x-0.8.8.drv-0/docbook2X-0.8.8/xslt/documentation'
make[1]: *** [Makefile:389: all-recursive] Error 1
make[1]: Leaving directory
'/tmp/guix-build-docbook2x-0.8.8.drv-0/docbook2X-0.8.8/xslt'
make: *** [Makefile:411: all-recursive] Error 1
error: in phase 'build': uncaught exception:
%exception #<&invoke-error program: "make" arguments: ("-j" "1")
exit-status: 2 term-signal: #f stop-signal: #f>
phase `build' failed after 0.4 seconds
command "make" "-j" "1" failed with status 2
build process 4 exited with status 256
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