It is the host directory generated in the output directory of Buildroot.
It contains absolute paths of where it has been generated, so cannot be shared directly.
To replace all absolute paths at once by the ones you are going to install the SDK to, execute:
find . -type f -name "*cmake*" -exec sed -i 's/</orig/absolute/path/to/output/host>/</new/absolute/path/to/output/host>/g' {} +
gdbserver in your Buildroot configuration (BR2_PACKAGE_GDB_SERVER), rebuild your config and flash it to your target (note: you can also just transfer the gdbserver binary to your target through ssh)gdbserver:# gdbserver <your_executable> [its_arguments]
output directory, run the gdb of your toolchain:$ host/bin/<toolchain_prefix>-gdb # (e.g. host/bin/aarch64-linux-gnu-gdb)
staging environment:(gdb) set sysroot staging
gdb to gdbserver over the network:(gdb) target remote <target_ip>:3000 (3000 is the default port)
(gdb) cont
From gdb you can execute step-by-step if you want, but the most interesting is probably that you can retrieve the stacktrace after a segfault, using
(gdb) bt
You can also connect to gdbserver from you IDE, if necessary.