FreeBSD web build failed on build-web.ysv.freebsd.org

[User Www-data]

===> doc/books/porters-handbook (all)
--- book.parsed.xml ---
env XML_CATALOG_FILES="file:///usr/local/www/build/head/en_US.ISO8859-1/books/porters-handbook/catalog-cwd.xml  file:///usr/local/www/build/head/en_US.ISO8859-1/share/xml/catalog.xml  file:///usr/local/www/build/head/share/xml/catalog.xml  file:///usr/local/share/xml/catalog" /usr/local/bin/xmllint --nonet --noent --valid --dropdtd --xinclude /usr/local/www/build/head/en_US.ISO8859-1/books/porters-handbook/book.xml > book.parsed.xml.tmp
/usr/local/www/build/head/en_US.ISO8859-1/books/porters-handbook/versions/chapter.xml:2200: parser error : Entity 'man.iflib.4' not defined
	    <entry>11-STABLE after merging a TCP checksum fix to &man.iflib.4;
	                                                                      ^
/usr/local/www/build/head/en_US.ISO8859-1/books/porters-handbook/versions/chapter.xml:8790: parser error : chunk is not well balanced

^
/usr/local/www/build/head/en_US.ISO8859-1/books/porters-handbook/book.xml:82: parser error : Failure to process entity chap.versions
  &chap.versions;
                 ^
/usr/local/www/build/head/en_US.ISO8859-1/books/porters-handbook/book.xml:82: parser error : Entity 'chap.versions' not defined
  &chap.versions;
                 ^
*** [book.parsed.xml] Error code 1

make[4]: stopped in /usr/local/www/build/head/en_US.ISO8859-1/books/porters-handbook
1 error

make[4]: stopped in /usr/local/www/build/head/en_US.ISO8859-1/books/porters-handbook
*** [all] Error code 2

make[3]: stopped in /usr/local/www/build/head/en_US.ISO8859-1/books
1 error

make[3]: stopped in /usr/local/www/build/head/en_US.ISO8859-1/books
*** [all] Error code 2

make[2]: stopped in /usr/local/www/build/head/en_US.ISO8859-1
1 error

make[2]: stopped in /usr/local/www/build/head/en_US.ISO8859-1
*** [all-all] Error code 2

make[1]: stopped in /usr/local/www/build/head/en_US.ISO8859-1/htdocs/doc
1 error

make[1]: stopped in /usr/local/www/build/head/en_US.ISO8859-1/htdocs/doc
*** [all] Error code 2

make: stopped in /usr/local/www/build/head/en_US.ISO8859-1/htdocs
1 error

make: stopped in /usr/local/www/build/head/en_US.ISO8859-1/htdocs
       12.82 real         5.83 user         4.36 sys

latestrevision.timestamp "2018-09-25 19:59:21" 
latestrevision.committer "erj"		
latestrevision.number "52304"