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• GDB is a debugger for C (and C++)
• It allows you to do things like run the program up to a certain point then stop and print out the values of certain variables at that point, or step through the program one line at a time and print out the values of each variable after executing each line.

Build steps

Follow the link for RPi build steps- RDK-B R-Pi Build guide

GDB Installation

Build requirements- After repo steps needed below changes to install gdb in the image 

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For license related issues,  below changes are required in $YOCTO_BUILD/conf/local.conf

WHITELIST_GPL-3.0 += " gdb readline"
INCOMPATIBLE_LICENSE = "GPL-3.0 LGPL-3.0 AGPL-3.0"
PACKAGECONFIG_remove_pn-gdb = "readline"

For avoiding license related issues while creating rootfs, need to make similar change under openembedded-core

--- a/meta/recipes-devtools/gdb/gdb-9.1.inc
+++ b/meta/recipes-devtools/gdb/gdb-9.1.inc
@@ -1,4 +1,4 @@
-LICENSE = "GPLv2 & GPLv3 & LGPLv2 & LGPLv3"
+LICENSE = "GPLv2 & LGPLv2"

GDB is included in the package "tools-debug", so commonly the EXTRA_IMAGE_FEATURES would be set as follows:

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