Debug using GNU debugger

By default, the build enables the GNU debugger (GDB). If GDB is not enabled, follow these steps on the Linux host computer to enable GDB:

1. Go to the meta-qcom-distro/recipes-products/packagegroups directory and open the packagegroup-qcom-utilities.bb file.
2. Modify the packagegroup-qcom-utilities.bb file to add gdb in the package list. Skip this step if the package name is already present in the package list.
3. Ensure that the build incorporates the debug symbols.
   readelf --debug-dump=decodedline <BIN_FILE>
   
   Or
   objdump --syms <BIN_NAME> | grep -i 'debug'
   
   If the debug symbols aren’t enabled, compile all required executables or shared libraries with the -g compiler flag. To push debug symbols to the device, see Configure debug symbols.
4. Recompile and flash the build on the device.
5. To debug using GDB, run the following command on the device:
   gdb --pid 502
   
   Sample output:
   gdb: warning: Couldn't determine a path for the index cache directory.
   Copyright (C) 2022 Free Software Foundation, Inc.
   License GPLv3+: GNU GPL version 3 or later <http://gnu.org/licenses/gpl.html>
   This is free software: you are free to change and redistribute it.
   There is NO WARRANTY, to the extent permitted by law.
   Type "show copying" and "show warranty" for details.
   This GDB was configured as "aarch64-qcom-linux".
   Type "show configuration" for configuration details.
   For bug reporting instructions, please see:
   <https://www.gnu.org/software/gdb/bugs/>.
   Find the GDB manual and other documentation resources online at:
      <http://www.gnu.org/software/gdb/documentation/>.
   For help, type "help".
   Type "apropos word" to search for commands related to "word".
   Attaching to process 502
   Reading symbols from /usr/bin/tqftpserv...
   (No debugging symbols found in /usr/bin/tqftpserv)
   Reading symbols from /usr/lib/libqrtr.so.1...
   (No debugging symbols found in /usr/lib/libqrtr.so.1)
   Reading symbols from /lib/libc.so.6...
   Reading symbols from /lib/.debug/libc.so.6...
   Reading symbols from /lib/ld-linux-aarch64.so.1...
   Reading symbols from /lib/.debug/ld-linux-aarch64.so.1...
   [Thread debugging using libthread_db enabled]
   Using host libthread_db library "/lib/libthread_db.so.1".
   0x0000ffffab00ef34 in __GI___select (nfds=4, readfds=0xffffc2ec14f8, writefds=0x0, exceptfds=0x0, timeout=0x0) at ../sysdeps/unix/sysv/linux/select.c:69
   69      ../sysdeps/unix/sysv/linux/select.c: No such file or directory.
   (gdb)
   (gdb)
   (gdb)
   (gdb)
   

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GDB commands

The following table lists the commonly used GDB commands. Table: Common GDB commands For more information, see Linux manual page.