[Texmacs-dev] Reproducible crash in TeXmacs

[Norbert Nemec]

Opening the attached file causes a crash in TeXmacs, saying:

   Fatal error: zero lines in insertion in 'pager_rep::pages_format'

This is a bug that I described in an earlier mail but failed to 
reproduce reliably back than. Now I managed to isolate the situation in 
a minimal file. Of course, the file as it is is a bit constructed, but 
the situation occurs rather frequently in my work:

As far as I could make out, the problem in "pager_rep" is as follows:

break_pages produces a pages in such a way that one page contains a 
single "page-this-header".
The subsequent running of
   pager_rep::pages_format (array<page_item> l, SI ht, SI tcor, SI bcor)
in make_pages.cpp:52 handles this specific tag specially, so it ends up 
with a completely empty page, throwing the fatal error.

Could anyone look into this matter? I invested quite a bit of time in 
isolating the bug this far but I could not get any further. :-(

Greetings,
Norbert

<TeXmacs|1.0.6.9>

<style|generic>

<\body>
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  <assign|page-this-footer|footer1>

  <assign|page-this-header|header1>

  <section|<new-page*>headline1>
</body>

<\initial>
  <\collection>
    <associate|page-flexibility|0.0>
    <associate|page-medium|paper>
    <associate|sfactor|10>
  </collection>
</initial>

<\references>
  <\collection>
    <associate|auto-1|<tuple|1|2>>
  </collection>
</references>

<\auxiliary>
  <\collection>
    <\associate|toc>
      
<vspace*|1fn><with|font-series|<quote|bold>|math-font-series|<quote|bold>|<new-page*>headline>
      
<datoms|<macro|x|<repeat|<arg|x>|<with|font-series|medium|<with|font-size|1|<space|0.2fn>.<space|0.2fn>>>>>|<htab|5mm>>
      <no-break><pageref|auto-1><vspace|0.5fn>
    </associate>
  </collection>
</auxiliary>