[pdftex] pdftex core dump when including certain pdf files

[Werner LEMBERG]

> ​can you provide a minimal example demonstrating the problem?

I can't.  We don't have something working yet.

> pdftex can merge Type1 subfonts in included pdfs.

Well, yes, but lilypond's music fonts are OpenType fonts...

For building the documentation, we use ghostscript's `.loadfont'
operator in the EPS files generated by lilypond.  Unfortunately,
ghostscript doesn't support OTCs (OpenType Collections) yet – support
is planned according to the developers but it is not an important
issue for them currently.[*]

  http://bugs.ghostscript.com/show_bug.cgi?id=696808

Regardless of this problem, the subsetted fonts generated by gs while
converting the EPS files to PDF can't be merged by pdftex (or xetex,
BTW).  For example, lilypond's central documentation file, the
notation reference, contains around 3500 such subsetted fonts (coming
from a few hundred included PDF snippets), based on 48 `normal' fonts.

For the new method, instead of using `.loadfont', we want to convert
the used OpenType fonts to bare CFF resources, extracting them from
OTCs where necessary.  TTFs are converted to Type 42 resoures, and all
fonts are collected in a `resource directory'.  The intermediate PDFs
would refer to the files in that directory, and the final output file
would eventually embed subsetted fonts derived from those resources.


    Werner


[*] There is no official support of OTFs and OTCs in PostScript.