Possible issue with Ubuntu Precise

mike42 commented 7 years ago

Noticed in install log that markdown_github support may not be available:

Checking foo.txt ..
pandoc: Unknown reader: markdown_github
/usr/bin/mdcheckr: line 35:  7875 Segmentation fault      xmllint --nowarning --html --xpath '*//a/@href' "$_inp_file" 2> /dev/null
/usr/bin/mdcheckr: line 44:  7879 Segmentation fault      xmllint --nowarning --html --xpath '*//img/@src' "$_inp_file" 2> /dev/null

mike42 commented 7 years ago

Two separate issues:

Pandoc issue

markdown works but markdown_github does not on this version.

Broken example:

$ pandoc --version
pandoc 1.9.1.1
Compiled with citeproc-hs 0.3.4, texmath 0.6.0.3, highlighting-kate 0.5.0.5.
Syntax highlighting is supported for the following languages:
    Actionscript, Ada, Alert, Alert_indent, Apache, Asn1, Asp, Awk, Bash,
    Bibtex, Boo, C, Changelog, Clojure, Cmake, Coffeescript, Coldfusion,
    Commonlisp, Cpp, Cs, Css, D, Diff, Djangotemplate, Doxygen, Dtd, Eiffel,
    Email, Erlang, Fortran, Fsharp, Gnuassembler, Go, Haskell, Haxe, Html, Ini,
    Java, Javadoc, Javascript, Json, Jsp, Latex, Lex, LiterateHaskell, Lua,
    Makefile, Mandoc, Matlab, Maxima, Metafont, Mips, Modula2, Modula3,
    Monobasic, Nasm, Noweb, Objectivec, Objectivecpp, Ocaml, Octave, Pascal,
    Perl, Php, Pike, Postscript, Prolog, Python, R, Relaxngcompact, Rhtml, Ruby,
    Scala, Scheme, Sci, Sed, Sgml, Sql, SqlMysql, SqlPostgresql, Tcl, Texinfo,
    Verilog, Vhdl, Xml, Xorg, Xslt, Xul, Yacc, Yaml
Copyright (C) 2006-2012 John MacFarlane
Web:  http://johnmacfarlane.net/pandoc
This is free software; see the source for copying conditions.  There is no
warranty, not even for merchantability or fitness for a particular purpose.

Working example:

$ pandoc --version
pandoc 1.17.2
Compiled with texmath 0.8.6.7, highlighting-kate 0.6.3.
Syntax highlighting is supported for the following languages:
    abc, actionscript, ada, agda, apache, asn1, asp, awk, bash, bibtex, boo, c,
    changelog, clojure, cmake, coffee, coldfusion, commonlisp, cpp, cs, css,
    curry, d, diff, djangotemplate, dockerfile, dot, doxygen, doxygenlua, dtd,
    eiffel, elixir, email, erlang, fasm, fortran, fsharp, gcc, glsl,
    gnuassembler, go, hamlet, haskell, haxe, html, idris, ini, isocpp, java,
    javadoc, javascript, json, jsp, julia, kotlin, latex, lex, lilypond,
    literatecurry, literatehaskell, llvm, lua, m4, makefile, mandoc, markdown,
    mathematica, matlab, maxima, mediawiki, metafont, mips, modelines, modula2,
    modula3, monobasic, nasm, noweb, objectivec, objectivecpp, ocaml, octave,
    opencl, pascal, perl, php, pike, postscript, prolog, pure, python, r,
    relaxng, relaxngcompact, rest, rhtml, roff, ruby, rust, scala, scheme, sci,
    sed, sgml, sql, sqlmysql, sqlpostgresql, tcl, tcsh, texinfo, verilog, vhdl,
    xml, xorg, xslt, xul, yacc, yaml, zsh
Default user data directory: /home/mike/.pandoc
Copyright (C) 2006-2016 John MacFarlane
Web:  http://pandoc.org
This is free software; see the source for copying conditions.
There is no warranty, not even for merchantability or fitness
for a particular purpose.
$ echo "aaa" | pandoc -f markdown
<p>aaa</p>
$ echo "aaa" | pandoc -f markdown_github
<p>aaa</p>

xmllint issue

Segmentation fault on the command we use is repeatable

Broken example:

$ xmllint --version 
xmllint: using libxml version 20708
   compiled with: Threads Tree Output Push Reader Patterns Writer SAXv1 FTP HTTP DTDValid HTML Legacy C14N Catalog XPath XPointer XInclude Iconv ISO8859X Unicode Regexps Automata Expr Schemas Schematron Modules Debug Zlib 
$ echo -n '<html></html>' | xmllint --nowarning --html --xpath '*//img/@src' -
Segmentation fault

Working example:

$ xmllint --version 
xmllint: using libxml version 20904
   compiled with: Threads Tree Output Push Reader Patterns Writer SAXv1 FTP HTTP DTDValid HTML Legacy C14N Catalog XPath XPointer XInclude Iconv ICU ISO8859X Unicode Regexps Automata Expr Schemas Schematron Modules Debug Zlib Lzma

Looks like requesting attributes of elements in an empty set causes the errors-

Ok:

echo -n '<a b="c"></a>' | xmllint --xpath '/a/@b' -

Segfault:

echo -n '<a b="c"></a>' | xmllint --xpath '/b/@b' -

mike42 / mdcheckr

Possible issue with Ubuntu Precise #16

Pandoc issue

xmllint issue