/bin/bash: error while loading shared libraries: libgcc_s.so.1

After a couple of Portage-based updates, including GCC, I was the victim of a loss of connection to my headless RaspberryPi server. Afterwards I was not able to use "su" or "sudo" because of the following error message:

error while loading shared libraries: libgcc_s.so.1: cannot open shared object file: No such file or directory

Background: I was connected to the server via SSH, as a standard user. I switched via su to root to do some portage updates and depclean. There was a problem setting the new GCC version during install and because of a deleted old GCC version the paths were not correct anymore. The new GCC library was there but the path in env.d were wrong (pointing to the old deletes version)

After a connection lost with SSH I lost my root shell from above and no more SSH connections were accepted. Luckily there was another standard user SSH connection opened. There I tried to switch to root again to set the correct paths (use gcc-config to set). But the mentioned error disallowed any "su" or "sudo" action.

I tried also to login using another shell, but at this moment I remembered only bash was available on this system and did not find anything suitable (searching for "sh" and "shell" only in my bin directory). I did not remember busybox which finally helped me to solve the error without restarting or connecting a monitor and keyboard to the server by setting the LD_LIBRARY_PATH and ran gcc-config:

/home/pjsb $ su -m -s /bin/bb root 
Passwort: 
/home/pjsb $ whoami 
root

/home/pjsb $ gcc-config -l 
/bin/bash: error while loading shared libraries: libgcc_s.so.1: cannot open shared object file: No such file or directory 
# setting the LD_LIBRARY_PATH did the final magic!!
/home/pjsb $ export LD_LIBRARY_PATH=/usr/lib/gcc/armv6j-hardfloat-linux-gnueabi/4.8.3/
/home/pjsb $ gcc-config -l 
 * gcc-config: Active gcc profile is invalid! 

 [1] armv6j-hardfloat-linux-gnueabi-4.8.3 
/home/pjsb $ gcc-config 1 
 * Switching native-compiler to armv6j-hardfloat-linux-gnueabi-4.8.3 ... 
>>> Regenerating /etc/ld.so.cache...                                                                                                               [ ok ] 

 * If you intend to use the gcc from the new profile in an already 
 * running shell, please remember to do: 
 *   . /etc/profile 

/home/pjsb $ . /etc/profile

Some inspirations and more background can be found at https://forums.gentoo.org/viewtopic-p-7639042.html