AppImage general questions and error

[dhudach]

I downloaded FlightGear-2020.3.8-x86_64.AppImage. The first question involves this error when I try to run it: /tmp/.mount_FlightAZX7c2/usr/bin/fgfs: symbol lookup error: /tmp/.mount_FlightAZX7c2/usr/bin/../lib/libQt5Gui.so.5: undefined symbol: hb_font_funcs_set_font_h_extents_func

I'm looking for some clues how to resolve this error.

Other than that, do I need to download/install anything else in order for AppImage to work properly, fgdata, etc?

Any help is greatly appreciated.

Thank you,
Dave

[dhudach]

I probably should have noted that I'm running Linux Mint and the error I posted occurs when I run from the command line. This is the full output:

Started with no arguments; assuming --launcher
0.09 [WARN]:gui QApplication: invalid style override passed, ignoring it.
0.09 [WARN]:gui UI languages: ("en-US")
/tmp/.mount_FlightAZX7c2/usr/bin/fgfs: symbol lookup error: /tmp/.mount_FlightAZX7c2/usr/bin/../lib/libQt5Gui.so.5: undefined symbol: hb_font_funcs_set_font_h_extents_func

I didn't see any guides or information on using the appimage file. If I missed something, please point to the links. For example, do I need to download and install anything else for appimage to work properly.

Thanks in advance,
Dave

[dhudach]

After doing some additional reading I do see that I need to download the Flight Gear data tar file. So I will do that. But I don't think that's going to resolve the initial runtime error. My suspicion is that I have an old qt lib file, but I'm not sure. Any help with this error will be greatly appreciated:

symbol lookup error: /tmp/.mount_FlightAZX7c2/usr/bin/../lib/libQt5Gui.so.5: undefined symbol: hb_font_funcs_set_font_h_extents_func

Thanks again,
Dave

[enrogue]

The undefined symbol is from harfbuzz - a font shaping engine - I need to check if the AppImage is attempting to link with it

[enrogue]

So the AppImage build tries not to include libraries that are considered core for most desktops - I'm guessing the setup assumes libharfbuzz.so.0 (provided by libharfbuzz0b on Ubuntu & assume something similar on Mint) is a core desktop library

Do you have the package libharfbuzz0b or equivalent installed? Just wondering if there's been a change in versions or it's a lib we need to look at forcing to include

[dhudach]

Thank you for responding. I will check to see if I have libharfbuzz0b installed. I think what puzzles me is that it's looking up the symbol in the file that is being mounted by App Image:

/tmp/.mount_FlightAZX7c2/usr/bin/../lib/libQt5Gui.so.5: undefined symbol: hb_font_funcs_set_font_h_extents_func

I will follow up on the above package and reply ...

Thank you again,
Dave

[dhudach]

Yes, libharfbuzz0b is installed version 1.0.1-1ubuntu0.1 for all of the following installed packages:

libharfbuzz0b
libharfbuzz-icu0
libharfbuzz-dev
libharfbuzz-gobject0

[enrogue]

OK version 1.0.1-1ubuntu0.1 is old - so the version of Mint you have is based on Ubuntu 16.04 (from checking the packaging info for harfbuzz on github)

The issue appears to be that it's compiled against harfbuzz 1.7.5 (it's compiled on Centos 7)

I can try forcing it to include harfbuzz in it's libraries, but that may cascade to other libraries

I'll build a test appimage & see what blows up...

[dhudach]

Thanks kindly for looking into this.

[enrogue]

OK including libharfbuzz in the AppImage doesn't seem to cause any issues & makes Ubuntu 16.04 work - I'll post a patch to the mailing list - hopefully 2020.3.9 will include the fix

Tested on Ubuntu 16.04 & 21.04 in addition to the build machine (Centos 7.

[dhudach]

Great, thank you. Will I be able to get the new AppImage from the FG download link?

Much appreciated.

Dave

[enrogue]

I haven't had any feedback yet, if/when it's included the AppImage should be available from the usual download place

[dhudach]

Awesome. Thank you again.

D

[dhudach]

Will the app image revision number be the same 2020.3.8 or will it change?

Thanks,
Dave

[enrogue]

It will be 2020.3.9 - there are now update fgdata txz files on sourceforge to upgrade fgdata from version to version