Crash due to OASIS opening

edited December 2009 in KLayout Support

I tried to load OASIS file 3.6G size to Klayout.
Due to load the tool reported :

Forward references to the S_GDS_PROPERTY name not allowed currently
(position = 3036274011, cell = $2719)

and crashed.

The OASIS file was created by Synopsys Astro and there was no problems to load it to Mentor's DesignRev.


  • edited 9:45PM

    Hi roman,

    I guess KLayout is somewhat too picky about the structure.

    The basic problem is that OASIS allows forward references which are hard to resolve in a single-pass parser. Single-pass parsers have the advantage of operating Faster on gzipped files for example. The problem you came across is one of the last limitations of the KLayout OASIS parser.

    This problem is somewhat tricky to solve in the general case. Currently one workaround is to remove the check by commenting out line 660 of (this applies to version 0.19.2). In effect however, properties will not be read correctly but the geometries will be valid.

    Best regards,


  • edited 9:45PM


    please try version 0.19.3 which I just put on the server.
    This one should be able to read your files.

    Best regards,


  • edited 9:45PM
    Hello Matthias,

    I've downloaded the new version and compiled it by:

    ./ -qt /usr/local/tools/qt/4.4.0 -platform linux-64-gcc-release

    The workstation I use is: Linux 2.6.9-78.ELsmp x86_64

    The tool was not crashed this time but it was stuck after read 3080M of 3.4G

    In top I see:

    Mem: 65987720k total, 38408292k used, 27579428k free, 148756k buffers
    Swap: 134217720k total, 709008k used, 133508712k free, 19595768k cached

    19891 roman 25 0 16.9g 16g 16m R 99.9 26.4 31:36.15 klayout
  • edited 9:45PM
    ... in addition I re-saved OASIS file with following compression flags in Mentor's DesignRev and the file was opened without any problem in Klayout 0.19.3 and also 0.19.2 versions.

    The Compression Flags I used:

    * Write CBlock compression
    * Write Strict Mode
    * Pattern Compression
  • edited December 2009

    Looks like I have to check the code again.

    Until then, it should be possible to avoid that problem by disabling the reading of properties using the "Reader Options" dialog in the "File" menu.

    Best regards,


  • edited 9:45PM
    Hello Matthias,

    I disabled reading of properties and now it works (the OASIS loaded into klayout)
    Thanks a lot , I'll wait for fix.
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