Table of Contents

Crash analysis on android

For native (Android) and Unity (Android) crashes, refer to the following instructions.

Getting crash locations during development

When debugging native programs on Android in Android Studio, set Debugger - Debug type to Dual (Java + Native) in Configuration settings.

crash Android configuratio

The information needed when debugging in Android Studio is shown below.

crash Android stack

Enter bt in lldb to get the crash reason and code stack trace, as shown below

(lldb) bt
* thread #16, name = 'samples.helloar', stop reason = signal SIGSEGV: invalid address (fault address: 0x9c40)
* frame #0: 0x0000004922f3a1d8 libEasyAR.so`___lldb_unnamed_symbol3056$$libEasyAR.so + 6088
    frame #1: 0x0000004922f38568 libEasyAR.so`___lldb_unnamed_symbol3054$$libEasyAR.so + 288
    frame #2: 0x0000004922f347f8 libEasyAR.so`___lldb_unnamed_symbol2876$$libEasyAR.so + 332
    frame #3: 0x00000049be2390c8 libc.so`__pthread_start(void*) + 40
    frame #4: 0x00000049be1f04f8 libc.so`__start_thread + 72

When the stack trace contains content related to libEasyAR.so, it may indicate the crash is related to EasyAR; if not present, there's a higher probability the crash is unrelated to EasyAR.

Enter image dump sections libEasyAR.so in lldb to get the load address of the dynamic library's .text section, as shown below

(lldb) image dump sections libEasyAR.so
...
  SectID     Type             Load Address                             Perm File Off.  File Size  Flags      Section Name
...
  0x00000010 code             [0x0000004922e30cfc-0x0000004923654558)  r-x  0x00256cfc 0x0082385c 0x00000006 libEasyAR.so..text
...

Getting crash locations after release

Crashes may also occur after release.

For reproducible crashes, try using Android Studio's built-in Profile/Debug tools. Then follow the same approach as during development to locate the crash.

crash Android debug

For hard-to-reproduce crashes, use crash reporting libraries to intercept application crash information and report it to servers. Note that crash information must include both the stack trace and module load addresses. Since Android introduced ASLR (Address Space Layout Randomization) starting from 4.0, module load addresses may change with each run, causing code addresses to vary dynamically. Only by knowing the relative value between code addresses in the stack and module load addresses can the crash location be determined.

When the stack trace contains content related to libEasyAR.so, it may indicate the crash is related to EasyAR; if not present, there's a higher probability the crash is unrelated to EasyAR.

  • EasyAR Sense and EasyAR Sense Unity Plugin version numbers

    e.g., 4.7.0.11800-cf8e24e30

  • Community/enterprise edition

  • CPU architecture

    aarch64/armeabi-v7a