Segmentation Fault in Kubuntu 18.04


  • 'Hi. I also have just come across the 'Segmentation fault (core dumped)' problem. I am running Kubuntu 18·04, and it was working fine last week. Now I just get the splash screen, which promptly disappears, and the program, then hangs.
    Any help would be appreciated, obviously  :) 

  • @Zierl Did you do any software updates recently?
  • I usually do all the updates that are suggested for Kubuntu, but I haven't done anything additionally. 
    This time, I started it from Konsole initially, rather than from the widget.

    The error message on this first attempt was:
    libpng warning: iCCP: known incorrect sRGB profile
    libpng warning: iCCP: known incorrect sRGB profile
    free(): invalid pointer
    Aborted (core dumped)

    It was only a subsequent run attempt that produced
    libpng warning: iCCP: known incorrect sRGB profile
    libpng warning: iCCP: known incorrect sRGB profile
    Segmentation fault (core dumped)

    I am in well over my head here

  • (I just split this into its own discussion, it was wondering off topic from the previous one)
  • Yeah, we've been having some issues with the underlying libraries that OpenLP uses (which are the same libraries that Kubuntu uses), but none of the issues we've seen have shown up during runtime.

    Maybe try backing up your data and your config, and starting OpenLP again? This shouldn't make a difference, but it at least helps us remove the data from the list of potential problems.
  • Hi @Zierl and @david_e_craddock

    Since we don't know why OpenLP is crashing, it is hard for us to debug this issue. But I have an idea that, if we're lucky, might help. OpenLP has "plugins" that handles image, songs, presentations, media etc, and maybe the crash is triggered by one of the plugins. If so OpenLP should start id the plugins are disabled.
    To disable the plugins open the following file in a text editor (such as gedit or kedit): /home/tgc/.config/OpenLP - /OpenLP.conf   - replace "tgc" with your own user name.
    In that file you will see the settings for OpenLP. Each section starts with "heading", like this "[songs]", which is the settings for songs. And for each plugin-section you will find a settings saying "status=1". By changing that to "status=0" that plugin will be disabled. So change status for plugins and save the file. Start OpenLP, and if it starts, try enabling the plugins one by one. If OpenLP does not start with all plugins disabled, we will atleast have ruled out the plugins as the problem...
    Please report back your findings!
    Best of luck!

  • HI. Sadly, I have disabled all the plug-ins, but still got the result: 
    libpng warning: iCCP: known incorrect sRGB profile
    libpng warning: iCCP: known incorrect sRGB profile
    free(): invalid pointer
    Aborted (core dumped)

    It is certainly a bit of a puzzle :(
  • Hi @Zierl and @david_e_craddock 
        Lets take this one step further....Make a backup of your data....See the manual if you have questions  Be sure your backup is not in the Data directory! A thumb drive, network drive or even you documents directory are good places to put your backup for what we are trying to do...

    1.    After you have made your backup, open a file explorer window to the Data directory....Same way you did it when you backed up your Data directory. 
    2. Make sure OpenLP is closed. Then delete all the folders in the Data directory.....As long as your backup was made, you don't have anything to worry about!  You can copy the backup into the data directory when we are done!
    3. Launch you still see the errors?  
    If you still see the errors than let us know.

    If don't see any errors;
    1. Try copying 2 folders at a time from your backup into the data directory....remember to shut down OpenLP before you copy into the Data directory....and make sure you are only doing a COPY....
    2. When you see the errors, delete the 2 folder from the Data folder that you copied last.
    3. Copy one folder at a time into your Data directory....
    4. Let us know what folder caused the errors to start happening.
  • I tried all suggestions. I even deleted all the Data folders, uninstalled and reinstalled OpenLP and still the program would not open. I am at a loss as to what the problem is. I will wait on the experts to do the next version to fix the issue. I know it can be a problem when the operating system makes changes that affect the software that then needs addressing.  Thanks for the suggestions and effort.
  • David you could try running a virtual Windows machine and running OpenLP in the virtual Windows machine.....if you can't wait...
  • edited August 2019
    Hi @david_e_craddock , I've tried to reproduce your error on a brand new installation of Kubuntu 18.04, and I can't seem to do it :frowning: Could I ask you to send me a list of all the installed packages on your system?

    From the command line:
    apt list --installed > installed.txt
    Then either upload the file here, or if you'd prefer I can reach out to you via e-mail, and you can send it to me.
  • Hi @david_e_craddock
    A way to track down the root cause is also to run OpenLP in a debugger.
    First you'll need to install the debugger : "sudo apt install gdb"
    Then run it: "gdb --args /usr/bin/python3.6 /usr/bin/openlp"
    This will start the debugger console, enter "r" and push enter to run OpenLP.
    OpenLP will then try to run and when it crashed you can enter "bt" into the debug console to get a traceback.
    Getting the complete output from the debugger would be helpful!
Sign In or Register to comment.