How to use addr2line in Android
Let's say that logcat show you the following crash log (this is from one of my projects):
I/DEBUG ( 31): *** *** *** *** *** *** *** *** *** *** *** *** *** *** *** ***
I/DEBUG ( 31): Build fingerprint: 'generic/sdk/generic:2.3/GRH55/79397:eng/test-keys'
I/DEBUG ( 31): pid: 378, tid: 386 >>> com.example.gltest <<<
I/DEBUG ( 31): signal 11 (SIGSEGV), code 1 (SEGV_MAPERR), fault addr 00000000
I/DEBUG ( 31): r0 001dbdc0 r1 00000001 r2 00000000 r3 00000000
I/DEBUG ( 31): r4 00000000 r5 40a40000 r6 4051a480 r7 42ddbee8
I/DEBUG ( 31): r8 43661b24 r9 42ddbed0 10 42ddbebc fp 41e462d8
I/DEBUG ( 31): ip 00000001 sp 436619d0 lr 83a12f5d pc 8383deb4 cpsr 20000010
I/DEBUG ( 31): #00 pc 0003deb4 /data/data/com.example.gltest/lib/libnativemaprender.so
I/DEBUG ( 31): #01 pc 00039b76 /data/data/com.example.gltest/lib/libnativemaprender.so
I/DEBUG ( 31): #02 pc 00017d34 /system/lib/libdvm.so
Look at the last 3 lines; this is your callstack. 'pc' is the program counter, and the pc for stack frame #00 gives you the address where the crash occurred. This is the number to pass to addr2line.
I'm using NDK r5, so the executable I'm using is located at $NDK/toolchains/arm-linux-androideabi-4.4.3/prebuilt/linux-x86/bin; make sure that is in your $PATH. The command to use looks like
arm-linux-androideabi-addr2line -C -f -e obj/local/armeabi/libXXX.so <address>
Or, for the case above:
arm-linux-androideabi-addr2line -C -f -e obj/local/armeabi/libnativemaprender.so 0003deb4
Which gives you the location of the crash.
Note:
- The -C flag is to demangle C++ code
- Use the .so file under obj/local/armeabi, since this is the non-stripped version
Also, when using NDK r5 with a 2.3 AVD, it is actually possible to debug multithreaded code.
There's an easier way to do this now (ndk-r7). Check out the ndk-stack command. The docs are in you_android_ndk_path/docs/NDK-STACK.html