In android development, we often encounter segmentation errors.That is sigsegv (11), at this time libc's backtrace will print the corresponding stack information, and what you see is just a pair of numbers,Seems impossible to check.

Such as the following string break error:

activitymanager (1105):displayed activity com.android.browser/.browseractivity:2460 ms (total 2460 ms)
i/debug (13002):*** *** *** *** *** *** *** *** *** *** *** *** *** *** * ** ***
i/debug (13002):build fingerprint:"unknown"
i/debug (13002):pid:20363, tid:20375>>>com.android.browser<<<
i/debug (13002):signal 11 (sigsegv), fault addr ffc00000
i/debug (13002):r0 059fc2a0 r1 4a3bcef8 r2 e59fc2a0 r3 4a3bcc58
i/debug (13002):r4 4a3bc101 r5 4ebe0a3c r6 4a3bc120 r7 012fff10
i/debug (13002):r8 500de101 r9 500ee12d 10 a87dfb20 fp 4ebe58e0
i/debug (13002):ip ffc00000 sp 4ebe0a30 lr 4a3bcc58 pc a862f3a0 cpsr 00000030
i/debug (13002):d0 0000001100000011 d1 0000001100000011
i/debug (13002):d2 0000001100000011 d3 0000001100000011
i/debug (13002):d4 0000001100000011 d5 0000001100000011
i/debug (13002):d6 0000001100000011 d7 4060000000000080
i/debug (13002):d8 41d3d1762e40d70a d9 41d3d1762e440a3d
i/debug (13002):d10 0000000000000000 d11 0000000000000000
i/debug (13002):d12 0000000000000000 d13 0000000000000000
i/debug (13002):d14 0000000000000000 d15 0000000000000000
i/debug (13002):d16 3ff0000000000000 d17 3ff0000000000000
i/debug (13002):d18 40cd268000000000 d19 3f3b9cc1b0bac000
i/debug (13002):d20 3ff0000000000000 d21 8000000000000000
i/debug (13002):d22 0000000000000000 d23 0000000000000000
i/debug (13002):d24 3ff0000000000000 d25 0000000000000000
i/debug (13002):d26 0000000000000000 d27 0000000000000000
i/debug (13002):d28 0000000000000000 d29 3ff0000000000000
i/debug (13002):d30 0000000000000000 d31 3ff0000000000000
i/debug (13002):scr 60000013
i/debug (13002):
i/debug (13002):#00 pc 0032f3a0 /system/lib/libwebcore.so
i/debug (13002):#01 pc 003243b0 /system/lib/libwebcore.so
i/debug (13002):#02 pc 003167b2 /system/lib/libwebcore.so
i/debug (13002):#03 pc 0038f2de /system/lib/libwebcore.so
i/debug (13002):#04 pc 0038f416 /system/lib/libwebcore.so
i/debug (13002):#05 pc 0030d392 /system/lib/libwebcore.so
i/debug (13002):#06 pc 003796e2 /system/lib/libwebcore.so
i/debug (13002):#07 pc 0038e36a /system/lib/libwebcore.so
i/debug (13002):#08 pc 003189f0 /system/lib/libwebcore.so
i/debug (13002):#09 pc 00377f82 /system/lib/libwebcore.so
i/debug (13002):#10 pc 0037ae0c /system/lib/libwebcore.so
i/debug (13002):#11 pc 0038e254 /system/lib/libwebcore.so
i/debug (13002):#12 pc 003189f0 /system/lib/libwebcore.so
i/debug (13002):#13 pc 0031cf2c /system/lib/libwebcore.so
i/debug (13002):#14 pc 0038e52a /system/lib/libwebcore.so
i/debug (13002):#15 pc 0038c2d0 /system/lib/libwebcore.so
i/debug (13002):#16 pc 0031cf76 /system/lib/libwebcore.so
i/debug (13002):#17 pc 0038e546 /system/lib/libwebcore.so
i/debug (13002):#18 pc 003189f0 /system/lib/libwebcore.so
i/debug (13002):#19 pc 0031ca40 /system/lib/libwebcore.so
i/debug (13002):#20 pc 0038e3be /system/lib/libwebcore.so
i/debug (13002):#21 pc 0038c2d0 /system/lib/libwebcore.so
i/debug (13002):#22 pc 0031cf76 /system/lib/libwebcore.so
i/debug (13002):#23 pc 0038e546 /system/lib/libwebcore.so
i/debug (13002):#24 pc 0038c2d0 /system/lib/libwebcore.so
i/debug (13002):#25 pc 00379054 /system/lib/libwebcore.so
i/debug (13002):#26 pc 0031d254 /system/lib/libwebcore.so
i/debug (13002):#27 pc 0030d5d6 /system/lib/libwebcore.so
i/debug (13002):#28 pc 0030d7d2 /system/lib/libwebcore.so
i/debug (13002):#29 pc 0031e354 /system/lib/libwebcore.so
i/debug (13002):#30 pc 0034ab3c /system/lib/libwebcore.so
i/debug (13002):
i/debug (13002):code around pc:
i/debug (13002):a862f380 469e4694 cc04f853 0e04f1a3 510cea4f
i/debug (13002):a862f390 f41c0d09 bf080f00 44714249 c008f8d1
i/debug (13002):a862f3a0 e000f8dc 0c1ff10e bf0842b8 2d04f853
i/debug (13002):a862f3b0 0d010510 0f00f412 4249bf08 f8c2185a
i/debug (13002):a862f3c0 e006c008 d1042b0c 99019b05 18426818
i/debug (13002):
i/debug (13002):code around lr:
i/debug (13002):4a3bcc38 e58d0000 e49d0004 e598200b e582002f
i/debug (13002):4a3bcc48 e52d0004 e3100001 0a000018 e3a03030
i/debug (13002):4a3bcc58 e59fc2a0 e002100c e59fc29c e151000c
i/debug (13002):4a3bcc68 0a000012 e59fc294 e002100c e0813003
i/debug (13002):4a3bcc78 e1a03123 e1c2200c e3530b02 ba000004
i/debug (13002):
i/debug (13002):stack:
i/debug (13002):4ebe09f0 50bfd848
i/debug (13002):4ebe09f4 50bfd858
i/debug (13002):4ebe09f8 50bfd834
i/debug (13002):4ebe09fc afd19a05 /system/lib/libc.so
i/debug (13002):4ebe0a00 50bd3264
i/debug (13002):4ebe0a04 a86510ef /system/lib/libwebcore.so
i/debug (13002):4ebe0a08 00000004
i/debug (13002):4ebe0a0c 50bfd854
i/debug (13002):4ebe0a10 002ece20 [heap]
i/debug (13002):4ebe0a14 4a3ba000
i/debug (13002):4ebe0a18 4ebe0a3c
i/debug (13002):4ebe0a1c 4ebe0a3c
i/debug (13002):4ebe0a20 4a3bc101
i/debug (13002):4ebe0a24 4ebe0a3c
i/debug (13002):4ebe0a28 df002777
i/debug (13002):4ebe0a2c e3a070ad
i/debug (13002):#00 4ebe0a30 002ece20 [heap]
i/debug (13002):4ebe0a34 49f627d0
i/debug (13002):4ebe0a38 a87d63c0 /system/lib/libwebcore.so
i/debug (13002):4ebe0a3c 4a3bd0e7
i/debug (13002):4ebe0a40 4a3bd0b8
i/debug (13002):4ebe0a44 4a3bcc58
i/debug (13002):4ebe0a48 00000003
i/debug (13002):4ebe0a4c 00000000
i/debug (13002):4ebe0a50 00001100
i/debug (13002):4ebe0a54 0000001f
i/debug (13002):4ebe0a58 00001074
i/debug (13002):4ebe0a5c 4ebe0b04
i/debug (13002):4ebe0a60 a87d63c0 /system/lib/libwebcore.so
i/debug (13002):4ebe0a64 4ebe0acc
i/debug (13002):4ebe0a68 4a3bc101
i/debug (13002):4ebe0a6c a86243b5 /system/lib/libwebcore.so
i/debug (13002):#01 4ebe0a70 4ebe0b38
i/debug (13002):4ebe0a74 00000064
i/debug (13002):4ebe0a78 003f0914 [heap]
i/debug (13002):4ebe0a7c fffffc00
i/debug (13002):4ebe0a80 50bfd834
i/debug (13002):4ebe0a84 a87d63c0 /system/lib/libwebcore.so
i/debug (13002):4ebe0a88 4ebe0b38
i/debug (13002):4ebe0a8c 4ebe0b04
i/debug (13002):4ebe0a90 4ebe0acc
i/debug (13002):4ebe0a94 a86167b7 /system/lib/libwebcore.so

The lib on our board is often stripped, and there is no symbol information.However, we can obtain the corresponding symbol information through the library generated during compilation.The compiler also provides us with the corresponding tool:addr2line full name:arm-eabi-addr2line, which can be found in the corresponding board source directory.

Through the fault analysis above,The library located at system/lib/libwebcore.so has broken errors.It can be pulled down and analyzed line by line.The command is:arm-eabi-addr2line -f -e ~/desktop/libwebcore.so 0038f2de

This analysis is also applicable to libraries developed using jni.

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