I downloaded gcc-arm-9.2-2019.12-x86_64-aarch64-none-linux-gnu.tar.xz and attempted to check which symbol versions the included libstdc++.so.6 provided:
$ ./gcc-arm-9.2-2019.12-x86_64-aarch64-none-linux-gnu/bin/aarch64-none-linux-gnu-objdump -T \
gcc…