[tex4ht] DVI error: stack empty at pop command, with tex4ht, only when using \usepackage[libertine]{newtxmath}

[Michal Hoftich]

Hi Nasser,

On Mon, Apr 2, 2018 at 7:24 AM, Nasser M. Abbasi <nma at 12000.org> wrote:
> I just found new problem. Using tex4ht on TL 2017.
>
> On one file I have, I can get tex4t to show this error
>
> ------------
> ......
> processing page 183
>   graphic size: 63.8874pt x 26.5726pt (22.4538mm x 9.33921mm)
>   output written to report-0183.svg
> processing page 184
>   DVI error: stack empty at pop command
> Make4ht: tex4ht  -cmozhtf -utf8 "report.dvi" can be executed only 1x
> Make4ht: t4ht  -p "report.dvi" can be executed only 1x
> Parse LG
> .....
> mv report-0182.svg re176x.svg
> mv report-0183.svg re177x.svg
> Image processing error: max_count exceeded
> Image processing error: max_count exceeded
> Image processing error: max_count exceeded
> Image processing error: max_count exceeded
> .....
> -------------------
>

It seems that Dvisvgm has some issue with the idv file. It is possible
that the problem is caused by the equation which is next to the last
image generated by Dvisvgm. You may try to isolate just few equations
around this point and try if it produces this issue as well.


> I've seen this problem before, 2016.
>
> "tex4ht] Too many DVI errors. stack empty at pop command"
> http://tug.org/pipermail/tex4ht/2016q1/001341.html
>
> If I simply comment out these 2 lines for tex4ht run:
>
> %\usepackage[T1]{fontenc}
> %\usepackage[libertine]{newtxmath}
>
> Then the error goes away.  I noticed when these lines
> are there, there are lots of font issues show in the log file,
> this is before the DVI error, like this

I think we didn't made the htf files for newtx fonts, as they use a
specific font encoding and I wasn't able to find correct Unicode chars
for it's symbols. Adding support for math fonts is much harder than
for text fonts which mostly use some standard encoding.

>> I do not know how to make a MWE now, since this file is large,
> contains 170 equations, about 290 pages.  On a small file,
> this error do not show up.
>
> I could do the following: Make a zip file that contains
> this self contained one latex file, and the main.mk4 file I
> use and the .cfg file and the command I used to compile it if
> someone wants to try to repoduce it.
>

Yes, it will be best, I think this will need some deeper look.

Best regards,
Michal