LuaLaTeX crashes when lua-widow-control and selnolig packages are used together

[stephanlukasczyk]

Issue

Loading lua-widow-control and the selnolig package together crashes LuaLaTeX due to some issue related to the debug library from Lua.

Expected Behavior

I expected that lua-widow-control wouldn't crash LuaLaTeX. When removing the loading of the selnolig package from the MWE, building a PDF succeeds.

Reproduction

\documentclass{scrartcl}
\listfiles
\usepackage{fontspec}% Required for selnolig
\usepackage{selnolig}
\usepackage[debug=true]{lua-widow-control}
\usepackage{blindtext}
\begin{document}
\blinddocument
\end{document}

Log File

This is LuaHBTeX, Version 1.17.0 (TeX Live 2023)  (format=lualatex 2023.7.11)  15 JUL 2023 08:33
 restricted system commands enabled.
**test.tex
(./test.tex
LaTeX2e <2023-06-01> patch level 1
L3 programming layer <2023-06-30>
Lua module: luaotfload 2022-10-03 3.23 Lua based OpenType font support
Lua module: lualibs 2022-10-04 2.75 ConTeXt Lua standard libraries.
Lua module: lualibs-extended 2022-10-04 2.75 ConTeXt Lua libraries -- extended c
ollection.
luaotfload | conf : Root cache directory is "/Users/stephan/Library/texlive/2023
/texmf-var/luatex-cache/generic/names".
luaotfload | init : Loading fontloader "fontloader-2022-10-03.lua" from kpse-res
olved path "/usr/local/texlive/2023/texmf-dist/tex/luatex/luaotfload/fontloader-
2022-10-03.lua".
Lua-only attribute luaotfload@noligature = 1
luaotfload | init : Context OpenType loader version 3.120
Inserting `luaotfload.node_processor' in `pre_linebreak_filter'.
Inserting `luaotfload.node_processor' in `hpack_filter'.
Inserting `luaotfload.glyph_stream' in `glyph_stream_provider'.
Inserting `luaotfload.define_font' in `define_font'.
Lua-only attribute luaotfload_color_attribute = 2
luaotfload | conf : Root cache directory is "/Users/stephan/Library/texlive/2023
/texmf-var/luatex-cache/generic/names".
Inserting `luaotfload.harf.strip_prefix' in `find_opentype_file'.
Inserting `luaotfload.harf.strip_prefix' in `find_truetype_file'.
Removing  `luaotfload.glyph_stream' from `glyph_stream_provider'.
Inserting `luaotfload.harf.glyphstream' in `glyph_stream_provider'.
Inserting `luaotfload.harf.finalize_vlist' in `post_linebreak_filter'.
Inserting `luaotfload.harf.finalize_hlist' in `hpack_filter'.
Inserting `luaotfload.cleanup_files' in `wrapup_run'.
Inserting `luaotfload.harf.finalize_unicode' in `finish_pdffile'.
Inserting `luaotfload.glyphinfo' in `glyph_info'.
Lua-only attribute luaotfload.letterspace_done = 3
Inserting `luaotfload.aux.set_sscale_dimens' in `luaotfload.patch_font'.
Inserting `luaotfload.aux.set_font_index' in `luaotfload.patch_font'.
Inserting `luaotfload.aux.patch_cambria_domh' in `luaotfload.patch_font'.
Inserting `luaotfload.aux.fixup_fontdata' in `luaotfload.patch_font_unsafe'.
Inserting `luaotfload.aux.set_capheight' in `luaotfload.patch_font'.
Inserting `luaotfload.aux.set_xheight' in `luaotfload.patch_font'.
Inserting `luaotfload.rewrite_fontname' in `luaotfload.patch_font'.
Inserting `tracingstacklevels' in `input_level_string'. (/usr/local/texlive/202
3/texmf-dist/tex/latex/koma-script/scrartcl.cls
Document Class: scrartcl 2023/07/07 v3.41 KOMA-Script document class (article)
(/usr/local/texlive/2023/texmf-dist/tex/latex/koma-script/scrkbase.sty
Package: scrkbase 2023/07/07 v3.41 KOMA-Script package (KOMA-Script-dependent b
asics and keyval usage)

(/usr/local/texlive/2023/texmf-dist/tex/latex/koma-script/scrbase.sty
Package: scrbase 2023/07/07 v3.41 KOMA-Script package (KOMA-Script-independent 
basics and keyval usage)

(/usr/local/texlive/2023/texmf-dist/tex/latex/koma-script/scrlfile.sty
Package: scrlfile 2023/07/07 v3.41 KOMA-Script package (file load hooks)

(/usr/local/texlive/2023/texmf-dist/tex/latex/koma-script/scrlfile-hook.sty
Package: scrlfile-hook 2023/07/07 v3.41 KOMA-Script package (using LaTeX hooks)


(/usr/local/texlive/2023/texmf-dist/tex/latex/koma-script/scrlogo.sty
Package: scrlogo 2023/07/07 v3.41 KOMA-Script package (logo)
)))
(/usr/local/texlive/2023/texmf-dist/tex/latex/graphics/keyval.sty
Package: keyval 2022/05/29 v1.15 key=value parser (DPC)
\KV@toks@=\toks17
)
Applying: [2021/05/01] Usage of raw or classic option list on input line 252.
Already applied: [0000/00/00] Usage of raw or classic option list on input line
 368.
))
(/usr/local/texlive/2023/texmf-dist/tex/latex/koma-script/tocbasic.sty
Package: tocbasic 2023/07/07 v3.41 KOMA-Script package (handling toc-files)
\scr@dte@tocline@numberwidth=\skip48
\scr@dte@tocline@numbox=\box51
)
Package tocbasic Info: omitting babel extension for `toc'
(tocbasic)             because of feature `nobabel' available
(tocbasic)             for `toc' on input line 133.
Class scrartcl Info: File `scrsize11pt.clo' used instead of
(scrartcl)           file `scrsize11.clo' to setup font sizes on input line 244
1.

(/usr/local/texlive/2023/texmf-dist/tex/latex/koma-script/scrsize11pt.clo
File: scrsize11pt.clo 2023/07/07 v3.41 KOMA-Script font size class option (11pt
)
luaotfload | db : Font names database loaded from /Users/stephan/Library/texlive
/2023/texmf-var/luatex-cache/generic/names/luaotfload-names.luc.gz)
(/usr/local/texlive/2023/texmf-dist/tex/latex/koma-script/typearea.sty
Package: typearea 2023/07/07 v3.41 KOMA-Script package (type area)
\ta@bcor=\skip49
\ta@div=\count183
\ta@hblk=\skip50
\ta@vblk=\skip51
\ta@temp=\skip52
\footheight=\skip53
Package typearea Info: These are the values describing the layout:
(typearea)             DIV  = 10
(typearea)             BCOR = 0.0pt
(typearea)             \paperwidth      = 597.50793pt
(typearea)              \textwidth      = 418.25555pt
(typearea)              DIV departure   = -6%
(typearea)              \evensidemargin = 17.3562pt
(typearea)              \oddsidemargin  = 17.3562pt
(typearea)             \paperheight     = 845.04694pt
(typearea)              \textheight     = 595.80026pt
(typearea)              \topmargin      = -25.16531pt
(typearea)              \headheight     = 17.0pt
(typearea)              \headsep        = 20.40001pt
(typearea)              \topskip        = 11.0pt
(typearea)              \footskip       = 47.6pt
(typearea)              \baselineskip   = 13.6pt
(typearea)              on input line 1799.
)
\c@part=\count184
\c@section=\count185
\c@subsection=\count186
\c@subsubsection=\count187
\c@paragraph=\count188
\c@subparagraph=\count189
\scr@dte@section@maxnumwidth=\skip54
Class scrartcl Info: using compatibility default `runin=bysign'
(scrartcl)           for `\section on input line 5082.
Class scrartcl Info: using compatibility default `afterindent=bysign'
(scrartcl)           for `\section on input line 5082.
\scr@dte@part@maxnumwidth=\skip55
Class scrartcl Info: using compatibility default `afterindent=false'
(scrartcl)           for `\part on input line 5090.
\scr@dte@subsection@maxnumwidth=\skip56
Class scrartcl Info: using compatibility default `runin=bysign'
(scrartcl)           for `\subsection on input line 5100.
Class scrartcl Info: using compatibility default `afterindent=bysign'
(scrartcl)           for `\subsection on input line 5100.
\scr@dte@subsubsection@maxnumwidth=\skip57
Class scrartcl Info: using compatibility default `runin=bysign'
(scrartcl)           for `\subsubsection on input line 5110.
Class scrartcl Info: using compatibility default `afterindent=bysign'
(scrartcl)           for `\subsubsection on input line 5110.
\scr@dte@paragraph@maxnumwidth=\skip58
Class scrartcl Info: using compatibility default `runin=bysign'
(scrartcl)           for `\paragraph on input line 5121.
Class scrartcl Info: using compatibility default `afterindent=bysign'
(scrartcl)           for `\paragraph on input line 5121.
\scr@dte@subparagraph@maxnumwidth=\skip59
Class scrartcl Info: using compatibility default `runin=bysign'
(scrartcl)           for `\subparagraph on input line 5131.
Class scrartcl Info: using compatibility default `afterindent=bysign'
(scrartcl)           for `\subparagraph on input line 5131.
\abovecaptionskip=\skip60
\belowcaptionskip=\skip61
\c@pti@nb@sid@b@x=\box52
Package tocbasic Info: omitting babel extension for `lof'
(tocbasic)             because of feature `nobabel' available
(tocbasic)             for `lof' on input line 6309.
\scr@dte@figure@maxnumwidth=\skip62
\c@figure=\count190
Package tocbasic Info: omitting babel extension for `lot'
(tocbasic)             because of feature `nobabel' available
(tocbasic)             for `lot' on input line 6325.
\scr@dte@table@maxnumwidth=\skip63
\c@table=\count191
Class scrartcl Info: Redefining `\numberline' on input line 6495.
\bibindent=\dimen139
)
(/usr/local/texlive/2023/texmf-dist/tex/latex/fontspec/fontspec.sty
(/usr/local/texlive/2023/texmf-dist/tex/latex/l3packages/xparse/xparse.sty
(/usr/local/texlive/2023/texmf-dist/tex/latex/l3kernel/expl3.sty
Package: expl3 2023-06-30 L3 programming layer (loader) 

(/usr/local/texlive/2023/texmf-dist/tex/latex/l3backend/l3backend-luatex.def
File: l3backend-luatex.def 2023-04-19 L3 backend support: PDF output (LuaTeX)
\l__color_backend_stack_int=\count192
Inserting `l3color' in `luaotfload.parse_color'.
\l__pdf_internal_box=\box53
))
Package: xparse 2023-02-02 L3 Experimental document command parser
)
Package: fontspec 2022/01/15 v2.8a Font selection for XeLaTeX and LuaLaTeX
Lua module: fontspec 2022/01/15 2.8a Font selection for XeLaTeX and LuaLaTeX (/
usr/local/texlive/2023/texmf-dist/tex/latex/fontspec/fontspec-luatex.sty
Package: fontspec-luatex 2022/01/15 v2.8a Font selection for XeLaTeX and LuaLaT
eX
\l__fontspec_script_int=\count193
\l__fontspec_language_int=\count194
\l__fontspec_strnum_int=\count195
\l__fontspec_tmp_int=\count196
\l__fontspec_tmpa_int=\count197
\l__fontspec_tmpb_int=\count198
\l__fontspec_tmpc_int=\count199
\l__fontspec_em_int=\count266
\l__fontspec_emdef_int=\count267
\l__fontspec_strong_int=\count268
\l__fontspec_strongdef_int=\count269
\l__fontspec_tmpa_dim=\dimen140
\l__fontspec_tmpb_dim=\dimen141
\l__fontspec_tmpc_dim=\dimen142

(/usr/local/texlive/2023/texmf-dist/tex/latex/base/fontenc.sty
Package: fontenc 2021/04/29 v2.0v Standard LaTeX package
)
(/usr/local/texlive/2023/texmf-dist/tex/latex/fontspec/fontspec.cfg)))
(/usr/local/texlive/2023/texmf-dist/tex/lualatex/selnolig/selnolig.sty
=== Package selnolig, Version 0.302, Date 2015/10/26 ===
Package: selnolig 2015/10/26
(/usr/local/texlive/2023/texmf-dist/tex/generic/iftex/ifluatex.sty
Package: ifluatex 2019/10/25 v1.5 ifluatex legacy package. Use iftex instead.

(/usr/local/texlive/2023/texmf-dist/tex/generic/iftex/iftex.sty
Package: iftex 2022/02/03 v1.0f TeX engine tests
))
(/usr/local/texlive/2023/texmf-dist/tex/luatex/luatexbase/luatexbase.sty
Package: luatexbase 2015/10/04 v1.3 luatexbase interface to LuaTeX 

(/usr/local/texlive/2023/texmf-dist/tex/luatex/ctablestack/ctablestack.sty
Package: ctablestack 2015/10/01 v1.0 Catcode table stable support
\@catcodetablestackcnt=\count270
)
\CatcodeTableOther=\catcodetable14
\CatcodeTableExpl=\catcodetable15
)
Inserting `Suppress ligatures selectively' in `ligaturing'.)
(/usr/local/texlive/2023/texmf-dist/tex/lualatex/lua-widow-control/lua-widow-co
ntrol.sty
Package: lua-widow-control 2022/11/22 vv3.0.0 Use Lua to remove widows and orph
ans
\g__lwc_emergencystretch_dim=\dimen143
\g__lwc_draftoffset_dim=\dimen144
\g__lwc_maxcost_int=\count271
Lua module: lua-widow-control 2022/11/22 3.0.0 
This module provides a LuaTeX-based solution to prevent
widows and orphans from appearing in a document. It does
so by increasing or decreasing the lengths of previous
paragraphs.
Lua-only attribute lua-widow-control_paragraph = 4
Lua-only attribute lua-widow-control_insert = 5
Lua function __lwc_if_enabled: = 25
Lua function __lwc_enable: = 26
Lua function __lwc_disable: = 27
Lua function __lwc_nobreak:n = 28
Lua function __lwc_debug:n = 29
Lua function __lwc_show_costs:n = 30
Lua function __lwc_show_colours:n = 31
Lua function __lwc_pre_shipout:n = 32...-dist/tex/luatex/lua-widow-control/lua-w
idow-control.lua:1735: attempt to index a boolean value (upvalue 'debug_lib').
<argument> \__lua_load_module_p:n {lua-widow-control}
                                          
l.124 }
     
? x


Here is how much of LuaTeX's memory you used:
 5871 strings out of 477545
 100000,1977958 words of node,token memory allocated 407 words of node memory still in use:
   2 hlist, 1 rule, 1 dir, 3 kern, 1 glyph, 4 attribute, 52 glue_spec, 4 attribu
te_list, 2 if_stack, 1 write, 1 user_defined nodes
   avail lists: 1:1,2:17,3:2,5:6,7:29,9:3,11:3
 26871 multiletter control sequences out of 65536+600000
 16 fonts using 855119 bytes
 108i,1n,101p,10908b,273s stack positions out of 10000i,1000n,20000p,200000b,200000s

warning  (pdf backend): no pages of output.

PDF statistics: 0 PDF objects out of 1000 (max. 8388607)
 0 named destinations out of 1000 (max. 131072)
 1 words of extra memory for PDF output out of 10000 (max. 100000000)

Format

LaTeX

Distribution

TeX Live

Distribution Version

2023

Lua-widow-control Version

3.0.0 (2022/11/22)

Other Relevant Packages and Versions

selnolig — 0.302 (2015/10/26)

Other

No response

[stephanlukasczyk]

Just found out that this seems to be caused by selnolig and not lua-widow-control, e.g., see zauguin/luaul#3 and micoloretan/selnolig#10. Since the author of selnolig did not release the fix for a couple of years now, could you imagine to have some workaround for the issue, maybe?

[gucci-on-fleek]

So selnolig.sty has these lines

  \newcommand\debugon{%
     \directlua{ debug=true }
  }
  \newcommand\debugoff{% 
     \directlua{ debug=false }
  }

which, as you've read in the linked issues, globally overwrites the Lua debug library. 3 possible solutions for this:

1. Restore the original debug library:

   \documentclass{article}
   
   \usepackage{fontspec}
   \usepackage{selnolig}
   
   \directlua{debug=require"debug";debug_info=function()end}
   \usepackage{lua-widow-control}
   
   \begin{document}
       Hello world!
   \end{document}

2. Use the secret method to prevent lua-widow-control from using the debug library:

   \documentclass{article}
   
   \usepackage{fontspec}
   \usepackage{selnolig}
   
   \directlua{LWC_NO_DEBUG=true}
   \usepackage{lua-widow-control}
   
   \begin{document}
       Hello world!
   \end{document}

3. Load lua-widow-control first:

   \documentclass{article}
   
   \usepackage{lua-widow-control}
   
   \usepackage{fontspec}
   \usepackage{selnolig}
   
   \begin{document}
       Hello world!
   \end{document}

The real solution here would be to patch selnolig, but considering the dates on the linked issues, that's probably not going to happen.

A more realistic solution here would be for me to patch the lua-widow-control source to work around this. I can't say that I'm terribly excited about needing a patch to fix a broken third-party package, but it's literally a two-line fix so I see no reason not to apply it.

[gucci-on-fleek]

Alright, this should be fixed 7c4544c. As soon as I get the build system to work again, I'll make a release and send it off to CTAN. After I submit it to CTAN, it usually takes about 2 days to make its way into TL, but this might take a little longer than usual since TUG2023 is running right now.

[stephanlukasczyk]

Thank you very much for the quick fix. No worries about the time for publication on CTAN, it's not really urgent, and I am also sitting in the audience of the TUG conference right now 😉