Android X86_64 App crashes before reaching Qt main.

[SMF-Qt]

@SMF-Qt

Unpacking the APK file shows that the libplugins_sqldrivers_qsqlmysql_x86_64.so is included:

libcrypto_3.so
libc++_shared.so
libplugins_iconengines_qsvgicon_x86_64.so
libplugins_imageformats_qgif_x86_64.so
libplugins_imageformats_qicns_x86_64.so
libplugins_imageformats_qico_x86_64.so
libplugins_imageformats_qjpeg_x86_64.so
libplugins_imageformats_qsvg_x86_64.so
libplugins_imageformats_qtga_x86_64.so
libplugins_imageformats_qtiff_x86_64.so
libplugins_imageformats_qwbmp_x86_64.so
libplugins_imageformats_qwebp_x86_64.so
libplugins_networkinformation_qandroidnetworkinformation_x86_64.so
libplugins_platforminputcontexts_qtvirtualkeyboardplugin_x86_64.so
libplugins_platforms_qtforandroid_x86_64.so
libplugins_qmltooling_qmldbg_debugger_x86_64.so
libplugins_qmltooling_qmldbg_inspector_x86_64.so
libplugins_qmltooling_qmldbg_local_x86_64.so
libplugins_qmltooling_qmldbg_messages_x86_64.so
libplugins_qmltooling_qmldbg_nativedebugger_x86_64.so
libplugins_qmltooling_qmldbg_native_x86_64.so
libplugins_qmltooling_qmldbg_preview_x86_64.so
libplugins_qmltooling_qmldbg_profiler_x86_64.so
libplugins_qmltooling_qmldbg_quick3dprofiler_x86_64.so
libplugins_qmltooling_qmldbg_quickprofiler_x86_64.so
libplugins_qmltooling_qmldbg_server_x86_64.so
libplugins_qmltooling_qmldbg_tcp_x86_64.so
libplugins_sqldrivers_qsqlite_x86_64.so
libplugins_sqldrivers_qsqlmysql_x86_64.so
libplugins_styles_qandroidstyle_x86_64.so
libplugins_tls_qcertonlybackend_x86_64.so
libplugins_tls_qopensslbackend_x86_64.so
libQPlastiqueStyle_x86_64.so
libQt6Concurrent_x86_64.so
libQt6Core_x86_64.so
libQt6Gui_x86_64.so
libQt6Network_x86_64.so
libQt6OpenGLWidgets_x86_64.so
libQt6OpenGL_x86_64.so
libQt6PrintSupport_x86_64.so
libQt6QmlMeta_x86_64.so
libQt6QmlModels_x86_64.so
libQt6QmlWorkerScript_x86_64.so
libQt6Qml_x86_64.so
libQt6Quick3DUtils_x86_64.so
libQt6Quick_x86_64.so
libQt6Sql_x86_64.so
libQt6Svg_x86_64.so
libQt6VirtualKeyboard_x86_64.so
libQt6Widgets_x86_64.so
libQtTest2_x86_64.so
libqwt_x86_64.so
libssl_3.so
libusb1.0.so
libzstd.so

[SMF-Qt]

@SMF-Qt

running:

readelf --dynamic libplugins_sqldrivers_qsqlmysql_x86_64.so| grep NEEDED

0x0000000000000001 (NEEDED) Shared library: [libmariadb.so]
0x0000000000000001 (NEEDED) Shared library: [libQt6Sql_x86_64.so]
0x0000000000000001 (NEEDED) Shared library: [libQt6Core_x86_64.so]
0x0000000000000001 (NEEDED) Shared library: [liblog.so]
0x0000000000000001 (NEEDED) Shared library: [libm.so]
0x0000000000000001 (NEEDED) Shared library: [libc++_shared.so]
0x0000000000000001 (NEEDED) Shared library: [libdl.so]
0x0000000000000001 (NEEDED) Shared library: [libc.so]

shows that the libmariadb.so (Mariadb connect library) has not been included in the APK.

What is the correct way to include this dependency for a plugin in an android context ?

[SMF-Qt]

@SMF-Qt

I linked my test app against the missing library and it got included in the APK (hack).

Now on the many occasions that the debugger does not end up on my break point in main() the following output is noted:

D/qt.core.plugin.factoryloader: Got keys from plugin meta data QList("QMYSQL", "QMARIADB")
D/qt.core.library: "/data/app/~~_QyhJ1cKweD6lRFr4k41Ew==/org.qtproject.example.QtTest2-ePOSiRm0FDBZIpSntSqqtQ==/base.apk!/lib/x86_64/libplugins_sqldrivers_qsqlmysql_x86_64.so" loaded library
I/default : main() returned -1
D/VRI[QtActivity]: visibilityChanged oldVisibility=true newVisibility=false
F/libc : FORTIFY: pthread_mutex_lock called on a destroyed mutex (0x71a943802ab8)
F/libc : FORTIFY: pthread_mutex_lock called on a destroyed mutex (0x71a943802ab8)
F/libc : Fatal signal 6 (SIGABRT), code -1 (SI_QUEUE) in tid 4670 (hwuiTask1), pid 4443 (example.QtTest2)
F/crash_dump64: crash_dump.cpp:627] failed to attach to thread 4670, already traced by 4562 (/data/user/0/org.qtproject.example.QtTest2/lldb-server)
F/libc : crash_dump helper failed to exec, or was killed
19:31:41: Debugging of has finished.
19:31:42: Android target "org.qtproject.example.QtTest2" died.

[SMF-Qt]

@SMF-Qt

To simplify things I have now written a simple app that pops a window and checks to see if it can open a mysql database on a remote server and writes a message on the state of the access.
The build for this app is clean and it finds the mariadb.so without prompting which is progress.

As a standard Linux build this works fine and reports that it has opened the database ok.

On an android simulator build the window pops up and reports that it cannot open the database.

I think the problem is with my mariadb connector plugin. Using wireshark I can see using the Linux test program:

192.168.0.2 192.168.1.2 TCP 74 3306 → 59544 [SYN, ACK] Seq=0 Ack=1 Win=65160 Len=0 MSS=1460 SACK_PERM TSval=3571608572 TSecr=4174219190 WS=128
192.168.1.2 192.168.0.2 TCP 66 59544 → 3306 [ACK] Seq=1 Ack=1 Win=64256 Len=0 TSval=4174219190 TSecr=3571608572
192.168.0.2 192.168.1.2 MySQL 159 Server Greeting proto=10 version=10.6.12-MariaDB
192.168.1.2 192.168.0.2 TCP 66 59544 → 3306 [ACK] Seq=1 Ack=94 Win=64256 Len=0 TSval=4174219191 TSecr=3571608573
192.168.1.2 192.168.0.2 MySQL 266 Login Request user=root db=test
192.168.0.2 192.168.1.2 TCP 66 3306 → 59544 [ACK] Seq=94 Ack=201 Win=65152 Len=0 TSval=3571608574 TSecr=4174219191
192.168.0.2 192.168.1.2 MySQL 86 Response OK
192.168.1.2 192.168.0.2 MySQL 88 Request Query
192.168.0.2 192.168.1.2 MySQL 177 Response OK
192.168.1.2 192.168.0.2 MySQL 75 Request Use Database
192.168.0.2 192.168.1.2 MySQL 86 Response OK
192.168.1.2 192.168.0.2 MySQL 83 Request Prepare Statement
192.168.0.2 192.168.1.2 MySQL 188 Response
192.168.1.2 192.168.0.2 MySQL 75 Request Close Statement
192.168.1.2 192.168.0.2 MySQL 95 Request Prepare Statement
192.168.0.2 192.168.1.2 TCP 66 3306 → 59544 [ACK] Seq=367 Ack=287 Win=65152 Len=0 TSval=3571608576 TSecr=4174219194
192.168.0.2 192.168.1.2 MySQL 82 Response
192.168.1.2 192.168.0.2 MySQL 75 Request Close Statement
192.168.1.2 192.168.0.2 MySQL 177 Request Query
192.168.0.2 192.168.1.2 TCP 66 3306 → 59544 [ACK] Seq=383 Ack=407 Win=65152 Len=0 TSval=3571608577 TSecr=4174219194
192.168.0.2 192.168.1.2 MySQL 167 Response TABULAR Response
192.168.1.2 192.168.0.2 MySQL 71 Request Quit
192.168.1.2 192.168.0.2 TCP 66 59544 → 3306 [FIN, ACK] Seq=412 Ack=484 Win=64256 Len=0 TSval=4174219195 TSecr=3571608577
192.168.0.2 192.168.1.2 TCP 66 3306 → 59544 [FIN, ACK] Seq=484 Ack=413 Win=65152 Len=0 TSval=3571608578 TSecr=4174219195
192.168.1.2 192.168.0.2 TCP 66 59544 → 3306 [ACK] Seq=413 Ack=485 Win=64256 Len=0 TSval=4174219196 TSecr=3571608578

Where the Android simulator version does:

192.168.1.2 192.168.0.2 TCP 74 45974 → 3306 [SYN] Seq=0 Win=64240 Len=0 MSS=1460 SACK_PERM TSval=4173921792 TSecr=0 WS=128
192.168.0.2 192.168.1.2 TCP 74 3306 → 45974 [SYN, ACK] Seq=0 Ack=1 Win=65160 Len=0 MSS=1460 SACK_PERM TSval=3571311174 TSecr=4173921792 WS=128
192.168.1.2 192.168.0.2 TCP 66 45974 → 3306 [ACK] Seq=1 Ack=1 Win=64256 Len=0 TSval=4173921792 TSecr=3571311174
192.168.0.2 192.168.1.2 MySQL 159 Server Greeting proto=10 version=10.6.12-MariaDB
192.168.1.2 192.168.0.2 TCP 66 45974 → 3306 [ACK] Seq=1 Ack=94 Win=64256 Len=0 TSval=4173921793 TSecr=3571311175
192.168.1.2 192.168.0.2 TCP 66 45974 → 3306 [FIN, ACK] Seq=1 Ack=94 Win=64256 Len=0 TSval=4173921793 TSecr=3571311175
192.168.0.2 192.168.1.2 TCP 66 3306 → 45974 [FIN, ACK] Seq=94 Ack=2 Win=65280 Len=0 TSval=3571311176 TSecr=4173921793
192.168.1.2 192.168.0.2 TCP 66 45974 → 3306 [ACK] Seq=2 Ack=95 Win=64256 Len=0 TSval=4173921794 TSecr=3571311176

My mariadb connector plugin setup must be wrong still, even though everything from building qt 6.9.1 through to this new app appears to build clean.

Any suggestions or input welcome.

[SMF-Qt]

Just built an arm64-v8a version and manually installed the apk file on my Samsung A06 phone and it behaves just like the X86_64 simulator.

[cristian-adam]

Regarding the Android debugger, have you set settings set plugin.jit-loader.gdb.enable off in Preferences > Debugger > GDB > Additional Attach Commands! as mentioned at https://forum.qt.io/topic/162125/android-debugging-stopping-in-disassembly-in-qt-creator-your-1-is-needed/ ?

But it looks like you can debug in other ways, and it won't help that much.

[SMF-Qt]

@cristian-adam

Thank you that has helped a lot I can now debug down through the Qt MySql plugin and reach the mariadb code.
Hopefully I can figure out what is wrong now.

[SMF-Qt]

@SMF-Qt

It looks like mariadb-connect-c tries to connect to the designated mysql server using ssl but this is not the default for mysql (mariadb) hence the disconnect.
If mariadb-connect-c is build with:
-DDEFAULT_SSL_VERIFY_SERVER_CERT=0

This does not happen and the database can be opened.

I need to look into this more but for now I can continue with my android build testing.

[SMF-Qt]

My full blown test app now runs on the X86_64 simulator it looks awful its ui was not designed for phone use but all the bells gongs and whistles are there and information from my database is populating the widgets which is good.

Time now to reflect on what I have learned and tidy up loose ends, thanks to those who helped on this journey.

[RokeJulianLockhart]

F/libc : crash_dump helper failed to exec, or was killed

@SMF-Qt, about that, follow stackoverflow.com/q/77202603.