前言:说真的Android NDK debug还是推荐lldb,gdb经常莫名其妙的不成功。不过下面的这个流程是谷歌官方建议的,还是有参考价值的。尤其是在App启动时Debug的流程。
lldb debug的文章推荐: https://fucknmb.com/2019/12/06/Flutter-Engine-C-%E6%BA%90%E7%A0%81%E8%B0%83%E8%AF%95%E5%88%9D%E6%8E%A2/
Sometimes you want to debug an app as it starts, such as when there's a crash and you want to step through code to see what happened before the crash. Attaching works in some cases, but in other cases is impossible because the app crashes before you can attach. The logwrapper
approach (used for strace
) doesn't always work because the app might not have permissions to open a port, and gdbserver
inherits that restriction.
To debug app startup, use the developer options in Settings to instruct the app to wait for a Java debugger to attach:
gdbserver
/gdbclient
normally, set breakpoints, then continue the process.To let the app run, attach a Java Debug Wire Protocol (JDWP) debugger such as Java Debugger (jdb):
adb forward tcp:12345 jdwp:XXX # (Where XXX is the PID
of the debugged process.)
jdb -attach localhost:12345
If you want debuggerd
to suspend crashed processes so that you can attach gdb
, set the appropriate property:
At the end of the usual crash output, debuggerd
provides instructions on how to connect gdb
using the command:
gdbclient.py -p PID
For 32-bit ARM, if you don’t have symbols, gdb
can't determine which instruction set it's disassembling (ARM or Thumb). To specify the instruction set chosen as the default when symbol information is missing, set the following property:
set arm fallback-mode arm # or thumb
GDB supports debugging platform code on Visual Studio Code. You can use the VS Code debugger frontend instead of the GDB CLI interface to control and debug native code running on devices.
Before using VS Code for debugging, install the C/C++ extension.
To debug code using VS Code:
gdbclient.py
are present.gdbclient.py
continues running. This is expected; don't kill the gdbclient.py
program.
launch.json
file and adds a new JSON object to a list.gdbclient.py
and paste it into the object you just deleted. Save the changes.reload window
.gdbclient.py
and press Enter to end the gdbclient.py
program.After setting up the debugger configuration for the first time, you can skip steps 3 through 6.
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