June 2026 - dev-luatex - Mailing Lists

Support for 8-byte xref offsets in PDF
by Charlotte Curtis 03 Jul '26

03 Jul '26

Hi all, I was advised to contact this list about a problem with LuaTex including PDFs created by Inkscape's new PDF exporter. I posted an issue on the Latex GitHub, where they quickly identified <https://github.com/latex3/latex2e/issues/2131#issuecomment-4792495907> that the problem is that our PDFs have 8-byte offsets in the xref table, while LuaTex only supports up to 4 bytes. Would it be possible for the PDF library in LuaTex to be updated to support more than 4 bytes per x-ref field? In the meantime, I'll look into restricting things on the authoring end (as realistically, 4 bytes should be enough in most cases). Thanks, Charlotte

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wrong shift of rules with left field
by Udi Fogiel 22 Jun '26

22 Jun '26

Hello, if a rule has a left field set the backend adds a shift to it, and this shift should be dependent on the outer direction (but it currently does not). I attached a patch with a fix. thanks, Udi

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italic correction between math letters
by Petr Olsak 16 Jun '26

16 Jun '26

Hello, I noticed a change between the versions LuaHBTeX 1.22.0 (TeX Live 2025) and LuaHBTeX 1.24.0 (TeX Live 2026). When I try to process this file by OpTeX: ----------------- \fontfam[lm] \tracingfonts=1 \setbox0=\hbox{$efff, {\_itletters efff}$} \showbox0 \bye ----------------- then I get following log with version 1.22.0: ----------------- This is LuaHBTeX, Version 1.22.0 (TeX Live 2025) (format=optex 2025.4.3) 16 JUN 2026 16:59 restricted system commands enabled. ... > \box0= \hbox(7.05+2.05)x46.76657, direction TLT .\mathon .\_mF ([latinmodern-math]:mode=base;ssty=0;mathsize=1;script=math;@10.0pt) 𝑒 .\_mF ([latinmodern-math]:mode=base;ssty=0;mathsize=1;script=math;@10.0pt) 𝑓 .\kern0.9 (italic) .\_mF ([latinmodern-math]:mode=base;ssty=0;mathsize=1;script=math;@10.0pt) 𝑓 .\kern0.9 (italic) .\_mF ([latinmodern-math]:mode=base;ssty=0;mathsize=1;script=math;@10.0pt) 𝑓 .\kern0.9 (italic) .\_mF ([latinmodern-math]:mode=base;ssty=0;mathsize=1;script=math;@10.0pt) , .\glue(\thinmuskip) 1.66663 .\hbox(7.05+2.05)x20.25998, direction TLT ..\_mF ([latinmodern-math]:mode=base;ssty=0;mathsize=1;script=latn;@10.0pt) 𝑒 ..\_mF ([latinmodern-math]:mode=base;ssty=0;mathsize=1;script=latn;@10.0pt) 𝑓 ..\_mF ([latinmodern-math]:mode=base;ssty=0;mathsize=1;script=latn;@10.0pt) 𝑓 ..\_mF ([latinmodern-math]:mode=base;ssty=0;mathsize=1;script=latn;@10.0pt) 𝑓 ..\kern0.9 (italic) .\mathoff ------------------- But when I do the same with version 1.24.0, I get: -------------------- This is LuaHBTeX, Version 1.24.0 (TeX Live 2026) (format=optex 2026.6.4) 16 JUN 2026 17:01 restricted system commands enabled. ... > \box0= \hbox(7.05+2.05)x48.56656, direction TLT .\mathon .\_mF ([latinmodern-math]:mode=base;ssty=0;mathsize=1;script=math;@10.0pt) 𝑒 .\_mF ([latinmodern-math]:mode=base;ssty=0;mathsize=1;script=math;@10.0pt) 𝑓 .\kern0.9 (italic) .\_mF ([latinmodern-math]:mode=base;ssty=0;mathsize=1;script=math;@10.0pt) 𝑓 .\kern0.9 (italic) .\_mF ([latinmodern-math]:mode=base;ssty=0;mathsize=1;script=math;@10.0pt) 𝑓 .\kern0.9 (italic) .\_mF ([latinmodern-math]:mode=base;ssty=0;mathsize=1;script=math;@10.0pt) , .\glue(\thinmuskip) 1.66663 .\hbox(7.05+2.05)x22.05997, direction TLT ..\_mF ([latinmodern-math]:mode=base;ssty=0;mathsize=1;script=latn;@10.0pt) 𝑒 ..\_mF ([latinmodern-math]:mode=base;ssty=0;mathsize=1;script=latn;@10.0pt) 𝑓 ..\kern0.9 (italic) ..\_mF ([latinmodern-math]:mode=base;ssty=0;mathsize=1;script=latn;@10.0pt) 𝑓 ..\kern0.9 (italic) ..\_mF ([latinmodern-math]:mode=base;ssty=0;mathsize=1;script=latn;@10.0pt) 𝑓 ..\kern0.9 (italic) .\mathoff -------------------- It means that the font with script=latn behaves equally as the font with sript=math, the italic corrections are inserted after each character if they are defined in the font. The older version 1.22.0 enabled me to switch off the inserting of italic corrections when script=latn. OK, maybe it is desired behavior. If so, then I am finding a solution of my problem: how to suppress italic correction between letters of math font in math mode? Best regards Petr Olšák

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coordinate corruption with spurious enddir node
by Udi Fogiel 12 Jun '26

12 Jun '26

Hello, There is a guard in hlist_out that check if an enddir is actually matching anything, his is done with checking dir_done. But dir_done is only set to 1 when a begindir is encountered, and never reset back. This can lead to a problem with the following: ....\begindir TRT ....\enddir TRT ....\glue(\spaceskip) 3.33 plus 1.665 minus 1.11....\enddir TLT the first couple save a state, then the spurious enddir restore the coordinates to a bogus value. This nodes structure can be achieved with e.g. \textdirection=0 \indent{\textdirection=1} \textdirection=0 abc\bye Note how the text is at the bottom left of the page. I attached a patch where dir_done is incremented in the begindir branch, and decreased if a matched enddir is found. Thanks, Udi

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Failed os.spawn() causes part of file to be read twice
by David Chiang 06 Jun '26

06 Jun '26

Greetings, a bug was reported at https://github.com/gregorio-project/gregorio/issues/1757 which appears to be a bug in LuaTeX. In the following program: main.tex: \documentclass{article} \begin{document} \input{fragment} \end{document} fragment.tex: \directlua{os.spawn('/does/not/exist')} text the word "text" should be printed once, but is actually printed twice. Please see the link above for the explanation of why this happens. I believe the fix is to open all files with O_CLOEXEC set. Thank you!

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