From subsecret
We need to change PATH and LD_LIBRARY_PATH to the new locations.
export PATH=/tools/bin/:${PATH} export LD_LIBRARY_PATH=/tools/lib
Now everything so far needs to be recompiled so the libraries and binaries are linked to /tools/lib/ld-linux-x86-64.so.2. The new path variable ensures the newly build GCC is used which will do the correct linking.