I was stuck with my app, as i am unable to debug as it is a multithreaded one and crashes with error SIGSEGV. I get lot of information on logcat, which gives me addresses in my native library. It'll helpfull if i can convert these addresses into my code.
Does anybody have any idea, how to use addr2line, which is provided with android-ndk?
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): signal11
(SIGSEGV), code1
(SEGV_MAPERR), fault addr00000000
I/DEBUG ( 31): r0001dbdc0 r1
00000001 r200000000 r3
00000000
I/DEBUG ( 31): r400000000 r5
40a40000 r64051a480 r7
42ddbee8
I/DEBUG ( 31): r843661b24 r9
42ddbed0 1042ddbebc fp
41e462d8
I/DEBUG ( 31): ip00000001 sp
436619d0 lr83a12f5d pc
8383deb4 cpsr20000010
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