crash: "Internal Error (0): Call to Object where the object was type 5, not the expected type 8"

[Mark Maxham]

Inkscape 0.91 r (Feb 12 2015) on Ubuntu 14.04

Possibly defective PDF, but does not crash (e.g.) Illustrator or Acrobat.

See attached PDF and this command line:

$ inkscape -z Ropes_Lightplot.pdf -l Ropes_Lightplot.svg

Output:

Syntax Error: Unknown character collection 'PDFTron-Identity'
Syntax Error: Unknown character collection 'PDFTron-Identity'
Syntax Error: Unknown character collection 'PDFTron-Identity'
Syntax Error: Unknown character collection 'PDFTron-Identity'
Syntax Error: Unknown character collection 'PDFTron-Identity'
Syntax Error: Unknown character collection 'PDFTron-Identity'
Syntax Error (1128185): Unexpected end of file in flate stream
Internal Error (0): Call to Object where the object was type 5, not the expected type 8

Emergency save activated!
Emergency save completed. Inkscape will close now.
If you can reproduce this crash, please file a bug at www.inkscape.org
with a detailed description of the steps leading to the crash, so we can fix it.
** Message: Error: Inkscape encountered an internal error and will close now

[Mark Maxham (mark-maxham)]

Also confirmed that 'pdf2svg' can successfully convert this test file.

[Alvin Penner (apenner)]

- reproduced on Windows 7, Inkscape 0.91 r13725 (Jan 30 2015)
- reproduced on Windows XP, Inkscape 0.91+devel r14600 (Jan 17 2016)
- using a File->Load in both cases. In 0.91 stable I get the DOS message:

Error: Unknown character collection 'PDFTron-Identity'

plus the attached popup message