Incompatible libpng version in application and library

Tom asso

My QtQuick application previously worked with Qt 5.12 and Ubuntu 16.04. Since then I've updated to Qt 5.13.0 and Ubuntu 18.04.03, and now the app segfaults when opening a file dialog:

libpng warning: Application jmp_buf size changed

Thread 1 "mbgrdviz" received signal SIGSEGV, Segmentation fault.
__longjmp_chk (env=0x0, val=1) at ../setjmp/longjmp.c:32
32	../setjmp/longjmp.c: No such file or directory.
(gdb) bt
#0  0x00007ffff4e43b00 in __longjmp_chk (env=0x0, val=1)
    at ../setjmp/longjmp.c:32
#1  0x00007fffb423bc9c in  ()
    at /usr/lib/x86_64-linux-gnu/gdk-pixbuf-2.0/2.10.0/loaders/libpixbufloader-png.so
#2  0x00007ffff08492c7 in png_error (png_ptr=0x555557fe6ad0, error_message=error_message@entry=0x7ffff0dd9cb8 "Incompatible libpng version in application and library") at libpng/pngerror.c:80
#3  0x00007ffff084c685 in png_create_read_struct_2 (user_png_ver=0x7fffb423ce57 "1.6.34", error_ptr=0x555557fd11a0, error_fn=0x7fffb423bc50, warn_fn=0x7fffb423cd10, mem_ptr=0x0, malloc_fn=0x7fffb423c320, free_fn=0x7fffb423afc0)
    at libpng/pngread.c:150

I've installed libpng16 on my system. I rebuilt Qt5.13.0 after configuring it to use the system libpng:

./configure -system-libpng
make 
make install

I've cleaned and rebuilt my app after these steps but still get the same segfault due to "Incompatible libpng version in application and library".
Suggested fixes?
I am building with qtcreator 4.11.1 - how can see exactly what libpng files it's compiling with and which libpng.so it's liking with?

Thanks
Tom

SGaist

Hi,

Are you using any external library with your application that also makes use if libpng ?

Tom asso

@SGaist - hm, I am linking with numerous third-party .so libraries. What is the best way to determine their possible dependence on libpng? Thanks!

Christian Ehrlicher

ldd is your friend

Tom asso

@Christian-Ehrlicher - 'ldd myprog | grep libpng' does not show any result, so I assume that means myprog doesn't rely on libpng dynamic library. What else should I check? Thanks!

SGaist

You should check all the third party libraries you are using.

Tom asso

@SGaist - Thanks - what tool should I use to check these libraries?

SGaist

The same tool: ldd

Tom asso

@SGaist - Hm, checked all of them with ldd - none show 'libpng*' in the list

SGaist

Any of these uses plugins ?

Tom asso

@SGaist - I do not think so, at least I didn't create any. To be sure I ran 'ldd -u -d -r ' on all *plugin.so files in my Qt5.13.0 directory, none of them show dependency on libpng.
Obviously something is invoking libpng routines, but I haven't found libpng dependency with ldd in any of my app's libraries....???

SGaist

Can you provide a full stack trace of your crash ?

Tom asso

@SGaist - yes, gdb stacktrace is below - thank you!

Thread 1 "mbgrdviz" received signal SIGSEGV, Segmentation fault.
__longjmp_chk (env=0x0, val=1) at ../setjmp/longjmp.c:32
32	../setjmp/longjmp.c: No such file or directory.
(gdb) bt
#0  0x00007ffff4e43b00 in __longjmp_chk (env=0x0, val=1)
    at ../setjmp/longjmp.c:32
#1  0x00007fffb423bc9c in  ()
    at /usr/lib/x86_64-linux-gnu/gdk-pixbuf-2.0/2.10.0/loaders/libpixbufloader-png.so
#2  0x00007ffff08492c7 in png_error (png_ptr=0x555557fde4f0, error_message=error_message@entry=0x7ffff0dd9cb8 "Incompatible libpng version in application and library") at libpng/pngerror.c:80
#3  0x00007ffff084c685 in png_create_read_struct_2 (user_png_ver=0x7fffb423ce57 "1.6.34", error_ptr=0x555557faf050, error_fn=0x7fffb423bc50, warn_fn=0x7fffb423cd10, mem_ptr=0x0, malloc_fn=0x7fffb423c320, free_fn=0x7fffb423afc0)
    at libpng/pngread.c:150
#4  0x00007fffb423befb in  ()
    at /usr/lib/x86_64-linux-gnu/gdk-pixbuf-2.0/2.10.0/loaders/libpixbufloader-png.so
#5  0x00007fffe07a408c in  ()
    at /usr/lib/x86_64-linux-gnu/libgdk_pixbuf-2.0.so.0
#6  0x00007fffe07a4955 in gdk_pixbuf_loader_close ()
    at /usr/lib/x86_64-linux-gnu/libgdk_pixbuf-2.0.so.0
#7  0x00007fffe07a120b in  ()
    at /usr/lib/x86_64-linux-gnu/libgdk_pixbuf-2.0.so.0
#8  0x00007fffe07a223c in gdk_pixbuf_new_from_stream ()
    at /usr/lib/x86_64-linux-gnu/libgdk_pixbuf-2.0.so.0
#9  0x00007fffe15ff142 in  () at /usr/lib/x86_64-linux-gnu/libgtk-3.so.0
#10 0x00007fffe15ff2bb in  () at /usr/lib/x86_64-linux-gnu/libgtk-3.so.0
#11 0x00007fffe15ffb46 in  () at /usr/lib/x86_64-linux-gnu/libgtk-3.so.0
#12 0x00007fffe15f74b2 in  () at /usr/lib/x86_64-linux-gnu/libgtk-3.so.0
#13 0x00007fffe172db3a in  () at /usr/lib/x86_64-linux-gnu/libgtk-3.so.0
#14 0x00007fffe15f5faa in  () at /usr/lib/x86_64-linux-gnu/libgtk-3.so.0
#15 0x00007fffe15aebf1 in  () at /usr/lib/x86_64-linux-gnu/libgtk-3.so.0
#16 0x00007fffe18058db in  () at /usr/lib/x86_64-linux-gnu/libgtk-3.so.0
#17 0x00007fffe15ec3ca in gtk_container_propagate_draw ()
    at /usr/lib/x86_64-linux-gnu/libgtk-3.so.0
#18 0x00007fffe15ec4b2 in  () at /usr/lib/x86_64-linux-gnu/libgtk-3.so.0
#19 0x00007fffe18058db in  () at /usr/lib/x86_64-linux-gnu/libgtk-3.so.0
#20 0x00007fffe15ec3ca in gtk_container_propagate_draw ()
    at /usr/lib/x86_64-linux-gnu/libgtk-3.so.0
#21 0x00007fffe15ec4b2 in  () at /usr/lib/x86_64-linux-gnu/libgtk-3.so.0
#22 0x00007fffe159fcf4 in  () at /usr/lib/x86_64-linux-gnu/libgtk-3.so.0
#23 0x00007fffe15f140d in  () at /usr/lib/x86_64-linux-gnu/libgtk-3.so.0
#24 0x00007fffe15f6063 in  () at /usr/lib/x86_64-linux-gnu/libgtk-3.so.0
#25 0x00007fffe15a2601 in  () at /usr/lib/x86_64-linux-gnu/libgtk-3.so.0
#26 0x00007fffe18058db in  () at /usr/lib/x86_64-linux-gnu/libgtk-3.so.0
#27 0x00007fffe15ec3ca in gtk_container_propagate_draw ()
    at /usr/lib/x86_64-linux-gnu/libgtk-3.so.0
#28 0x00007fffe175b1c0 in  () at /usr/lib/x86_64-linux-gnu/libgtk-3.so.0
#29 0x00007fffe15f140d in  () at /usr/lib/x86_64-linux-gnu/libgtk-3.so.0
#30 0x00007fffe15f6063 in  () at /usr/lib/x86_64-linux-gnu/libgtk-3.so.0
#31 0x00007fffe175ad35 in  () at /usr/lib/x86_64-linux-gnu/libgtk-3.so.0
#32 0x00007fffe18058db in  () at /usr/lib/x86_64-linux-gnu/libgtk-3.so.0
#33 0x00007fffe15ec3ca in gtk_container_propagate_draw ()
    at /usr/lib/x86_64-linux-gnu/libgtk-3.so.0
#34 0x00007fffe15ec4b2 in  () at /usr/lib/x86_64-linux-gnu/libgtk-3.so.0
#35 0x00007fffe159fcf4 in  () at /usr/lib/x86_64-linux-gnu/libgtk-3.so.0
#36 0x00007fffe15f140d in  () at /usr/lib/x86_64-linux-gnu/libgtk-3.so.0
#37 0x00007fffe15f6063 in  () at /usr/lib/x86_64-linux-gnu/libgtk-3.so.0
#38 0x00007fffe15a2601 in  () at /usr/lib/x86_64-linux-gnu/libgtk-3.so.0
#39 0x00007fffe18058db in  () at /usr/lib/x86_64-linux-gnu/libgtk-3.so.0
#40 0x00007fffe15ec3ca in gtk_container_propagate_draw ()
    at /usr/lib/x86_64-linux-gnu/libgtk-3.so.0
#41 0x00007fffe15ec4b2 in  () at /usr/lib/x86_64-linux-gnu/libgtk-3.so.0
#42 0x00007fffe172ffd7 in  () at /usr/lib/x86_64-linux-gnu/libgtk-3.so.0
#43 0x00007fffe18058db in  () at /usr/lib/x86_64-linux-gnu/libgtk-3.so.0
#44 0x00007fffe15ec3ca in gtk_container_propagate_draw ()
    at /usr/lib/x86_64-linux-gnu/libgtk-3.so.0
#45 0x00007fffe15ec4b2 in  () at /usr/lib/x86_64-linux-gnu/libgtk-3.so.0
#46 0x00007fffe159fcf4 in  () at /usr/lib/x86_64-linux-gnu/libgtk-3.so.0
#47 0x00007fffe15f140d in  () at /usr/lib/x86_64-linux-gnu/libgtk-3.so.0
#48 0x00007fffe15f6063 in  () at /usr/lib/x86_64-linux-gnu/libgtk-3.so.0
#49 0x00007fffe15a2601 in  () at /usr/lib/x86_64-linux-gnu/libgtk-3.so.0
#50 0x00007fffe18058db in  () at /usr/lib/x86_64-linux-gnu/libgtk-3.so.0
#51 0x00007fffe15ec3ca in gtk_container_propagate_draw ()
    at /usr/lib/x86_64-linux-gnu/libgtk-3.so.0
#52 0x00007fffe16ed820 in  () at /usr/lib/x86_64-linux-gnu/libgtk-3.so.0
#53 0x00007fffe15f140d in  () at /usr/lib/x86_64-linux-gnu/libgtk-3.so.0
#54 0x00007fffe15f6063 in  () at /usr/lib/x86_64-linux-gnu/libgtk-3.so.0
#55 0x00007fffe16ed6c1 in  () at /usr/lib/x86_64-linux-gnu/libgtk-3.so.0
#56 0x00007fffe18058db in  () at /usr/lib/x86_64-linux-gnu/libgtk-3.so.0
#57 0x00007fffe15ec3ca in gtk_container_propagate_draw ()
    at /usr/lib/x86_64-linux-gnu/libgtk-3.so.0
#58 0x00007fffe15ec4b2 in  () at /usr/lib/x86_64-linux-gnu/libgtk-3.so.0
#59 0x00007fffe159fcf4 in  () at /usr/lib/x86_64-linux-gnu/libgtk-3.so.0
#60 0x00007fffe15f140d in  () at /usr/lib/x86_64-linux-gnu/libgtk-3.so.0
#61 0x00007fffe15f6063 in  () at /usr/lib/x86_64-linux-gnu/libgtk-3.so.0
#62 0x00007fffe15a2601 in  () at /usr/lib/x86_64-linux-gnu/libgtk-3.so.0
#63 0x00007fffe18058db in  () at /usr/lib/x86_64-linux-gnu/libgtk-3.so.0
#64 0x00007fffe15ec3ca in gtk_container_propagate_draw ()
    at /usr/lib/x86_64-linux-gnu/libgtk-3.so.0
#65 0x00007fffe15ec4b2 in  () at /usr/lib/x86_64-linux-gnu/libgtk-3.so.0
#66 0x00007fffe159fcf4 in  () at /usr/lib/x86_64-linux-gnu/libgtk-3.so.0
#67 0x00007fffe15f140d in  () at /usr/lib/x86_64-linux-gnu/libgtk-3.so.0
#68 0x00007fffe15f6063 in  () at /usr/lib/x86_64-linux-gnu/libgtk-3.so.0
#69 0x00007fffe15a2601 in  () at /usr/lib/x86_64-linux-gnu/libgtk-3.so.0
#70 0x00007fffe18058db in  () at /usr/lib/x86_64-linux-gnu/libgtk-3.so.0
#71 0x00007fffe15ec3ca in gtk_container_propagate_draw ()
    at /usr/lib/x86_64-linux-gnu/libgtk-3.so.0
#72 0x00007fffe15ec4b2 in  () at /usr/lib/x86_64-linux-gnu/libgtk-3.so.0
#73 0x00007fffe159fcf4 in  () at /usr/lib/x86_64-linux-gnu/libgtk-3.so.0
#74 0x00007fffe15f140d in  () at /usr/lib/x86_64-linux-gnu/libgtk-3.so.0
#75 0x00007fffe15f6063 in  () at /usr/lib/x86_64-linux-gnu/libgtk-3.so.0
#76 0x00007fffe15a2601 in  () at /usr/lib/x86_64-linux-gnu/libgtk-3.so.0
#77 0x00007fffe18058db in  () at /usr/lib/x86_64-linux-gnu/libgtk-3.so.0
#78 0x00007fffe15ec3ca in gtk_container_propagate_draw ()
    at /usr/lib/x86_64-linux-gnu/libgtk-3.so.0
#79 0x00007fffe15ec4b2 in  () at /usr/lib/x86_64-linux-gnu/libgtk-3.so.0
#80 0x00007fffe18136ef in  () at /usr/lib/x86_64-linux-gnu/libgtk-3.so.0
#81 0x00007fffe18058db in  () at /usr/lib/x86_64-linux-gnu/libgtk-3.so.0
#82 0x00007fffe180e998 in  () at /usr/lib/x86_64-linux-gnu/libgtk-3.so.0
#83 0x00007fffe16b2859 in gtk_main_do_event ()
    at /usr/lib/x86_64-linux-gnu/libgtk-3.so.0
#84 0x00007fffe11c3765 in  () at /usr/lib/x86_64-linux-gnu/libgdk-3.so.0
#85 0x00007fffe11d37f5 in  () at /usr/lib/x86_64-linux-gnu/libgdk-3.so.0
#86 0x00007fffe11d49f6 in  () at /usr/lib/x86_64-linux-gnu/libgdk-3.so.0
#87 0x00007fffe11d4bf0 in  () at /usr/lib/x86_64-linux-gnu/libgdk-3.so.0
#88 0x00007fffdbdbc10d in g_closure_invoke ()
    at /usr/lib/x86_64-linux-gnu/libgobject-2.0.so.0
#89 0x00007fffdbdcf05e in  () at /usr/lib/x86_64-linux-gnu/libgobject-2.0.so.0
#90 0x00007fffdbdd7715 in g_signal_emit_valist ()
    at /usr/lib/x86_64-linux-gnu/libgobject-2.0.so.0
#91 0x00007fffdbdd812f in g_signal_emit ()
    at /usr/lib/x86_64-linux-gnu/libgobject-2.0.so.0
#92 0x00007fffe11ccac9 in  () at /usr/lib/x86_64-linux-gnu/libgdk-3.so.0
#93 0x00007fffe11b8080 in  () at /usr/lib/x86_64-linux-gnu/libgdk-3.so.0
#94 0x00007fffeca4ed03 in  () at /usr/lib/x86_64-linux-gnu/libglib-2.0.so.0
#95 0x00007fffeca4e285 in g_main_context_dispatch ()
    at /usr/lib/x86_64-linux-gnu/libglib-2.0.so.0
#96 0x00007fffeca4e650 in  () at /usr/lib/x86_64-linux-gnu/libglib-2.0.so.0
#97 0x00007fffeca4e6dc in g_main_context_iteration ()
    at /usr/lib/x86_64-linux-gnu/libglib-2.0.so.0
#98 0x00007ffff5d7118f in QEventDispatcherGlib::processEvents(QFlags<QEventLoop::ProcessEventsFlag>) (this=0x5555559fc4b0, flags=...)
    at kernel/qeventdispatcher_glib.cpp:423
#99 0x00007ffff5d17902 in QEventLoop::exec(QFlags<QEventLoop::ProcessEventsFlag>) (this=this@entry=0x7fffffffda70, flags=..., flags@entry=...)
    at kernel/qeventloop.cpp:225
#100 0x00007ffff5d20260 in QCoreApplication::exec() ()
    at kernel/qcoreapplication.cpp:1373
#101 0x000055555555a767 in main(int, char**) (argc=<optimized out>, argv=<optimized out>) at main.cpp:66

SGaist

Can you start your application with the QT_DEBUG_PLUGINS environment variable set 1 ?

Tom asso

@SGaist - Thank you. I do that and output shows multiple image libraries being loaded:

loaded library "/home/oreilly/Qt/5.13.0/gcc_64/plugins/imageformats/libqgif.so"
loaded library "/home/oreilly/Qt/5.13.0/gcc_64/plugins/imageformats/libqicns.so"
loaded library "/home/oreilly/Qt/5.13.0/gcc_64/plugins/imageformats/libqico.so"
loaded library "/home/oreilly/Qt/5.13.0/gcc_64/plugins/imageformats/libqjpeg.so"
loaded library "/home/oreilly/Qt/5.13.0/gcc_64/plugins/imageformats/libqsvg.so"
loaded library "/home/oreilly/Qt/5.13.0/gcc_64/plugins/imageformats/libqtga.so"
loaded library "/home/oreilly/Qt/5.13.0/gcc_64/plugins/imageformats/libqtiff.so"
loaded library "/home/oreilly/Qt/5.13.0/gcc_64/plugins/imageformats/libqwbmp.so"
loaded library "/home/oreilly/Qt/5.13.0/gcc_64/plugins/imageformats/libqwebp.so"

However these do not include libpng.so - probably because before building Qt I configured it to use my system's libpng; "./configure -system-libpng", while is libpng16. What else might the problem be?

SGaist

What QPA and theme plugins gets loaded ?

Tom asso

@SGaist - Thanks very much for your help!
I discovered which library is causing the problem. It's a non-Qt library that doesn't directly rely on libpng, but it does rely on 50+ other libraries - apparently one of those does directly or indirectly rely on libpng. Apparently ldd doesn't show recursive dependencies, which surprises me. https://stackoverflow.com/questions/15064685/does-ldd-also-show-dependencies-of-dependencies/15064784#15064784

SGaist

What library was it ?

Tom asso

@SGaist - the segfault occurs when I link with /usr/local/lib/libgmt.so.6.0.0, for the Generic Mapping Tools. I built the library from source and installed on this system. Yet when I run 'ldd /usr/local/lib/libgmt.so.6.0.0' it does not display any dependency on libpng - I don't understand why...

Tom asso

@SGaist - also tried installing libgmt-dev (rather than building myself) - I get the same segfault due to "Incompatible libpng version in application and library"