SyncTeX not working right with LuaLaTeX in TeX Live

Question

I am writing my documents using TeXstudio with TeX Live on Windows (all up to date). After typesetting a document with SyncTeX (which is the default), I should be able to Ctrl + Click into the PDF preview in order to move the cursor to the appropriate position in the source editor.

This works fine with pdflatex, but when using lualatex (which I do in most of my documents) I am often directed to a seemingly random position later in the file. The discrepancy can be quite large, spanning several pages. This is of course not ideal.

After searching the web a bit I discovered a bug report in TeXstudio's issue tracker from three years ago describing the same problem. The people there seemed to agree that it was an issue with TeX Live, as it didn't appear with MiKTeX.

So my questions are

• Can I do anything to remedy this? (I assume no.)
• Can some of you maybe confirm the behavior I see on your own setup? Does it appear independently of the editor? Can you confirm that it does not happen with MiKTeX?
• Is there a public bug tracker for TeX Live where I can check if this has already been reported? Or should I just write to the mailing list?
• Is this more likely a bug in LuaLaTeX, SyncTeX or something else?

(I do realize that this question (set) somewhat breaks the format of this site but I felt that it is useful.)

---

Here's an MWE for testing. On my system, clicking on "1", "2" or "3" takes me to 3, clicking on "4" or "5" takes me to 5 and the rest of the paragraphs take me where they should. I can also provide longer examples if required.

% !TeX program = lualatex
\documentclass{article}

\begin{document}

1

2

3

4

5

6

7

\end{document}

Answer 1

This very morning Akira Kakuto replied to a respective question on the [email protected] mailinglist:

There was a bug in SyncTeX, he has fixed it locally already, the fix will be available with TeX Live 2022.

Answer 2

• Your example works fine both with miktex and texlive when I use sumatra as viewer and winedt as editor.

• With texstudio I can confirm that it works with miktex but fails with texlive with lualatex but works with pdflatex.

If one expect the synctex files one can see one difference which could be the source of the problem:

miktex with lualatex

(1,6:8799518,8865054:22609920,436470,0
h1,5:8799518,8865054:983040,0,0
x1,5:10110238,8865054          %<---------
g1,6:31409438,8865054
g1,6:31409438,8865054
)

texlive with lualatex

(1,6:8799518,8865054:22609920,436470,0
h1,5:8799518,8865054:983040,0,0
x1,5:10110238,0                %<--------- 
g1,6:31409438,8865054
g1,6:31409438,8865054
)

texlive with pdflatex

(1,6:8799518,8865054:22609920,422343,0
h1,5:8799518,8865054:983040,0,0
x1,5:10110239,8865054          %<---------  
k1,6:31409438,8865054:21299199
g1,6:31409438,8865054
)

I can't tell you if it is a bug in lualatex to produce a zero there, or if it is a bug in texstudio that it (probably) can't handle it. Your best bet for an answer is probably the texlive mailing list.

Update

Akira Kakuto announced a change in luatex for texlive 2022.