[ruslandh]

Zur0
Ну тут Вы ошибаетесь - это только часть, что надо сделать для смены версии gcc. Привиду лог скрипта select-gcc (для примера) :

Setting up automatic selection of i586-alt-linux-cpp.
Checking available versions of i586-alt-linux-cpp, updating links in /etc/altern
atives ...
(You may modify the symlinks there yourself if desired - see `man ln'.)
Updating i586-alt-linux-cpp (/usr/bin/i586-alt-linux-cpp) to point to /usr/bin/i
586-alt-linux-cpp-3.2.
Leaving cpp.1.bz2 (/usr/share/man/man1/cpp.1.bz2) pointing to /usr/share/man/man
1/cpp-3.2.1.bz2.

Setting up automatic selection of gcc.
Checking available versions of gcc, updating links in /etc/alternatives ...
(You may modify the symlinks there yourself if desired - see `man ln'.)
Updating gcc (/usr/bin/gcc) to point to /usr/bin/colorifer.
Leaving g77 (/usr/bin/g77) pointing to /usr/bin/colorifer.
Leaving gcj (/usr/bin/gcj) pointing to /usr/bin/colorifer.
Leaving g++ (/usr/bin/g++) pointing to /usr/bin/colorifer.

Setting up automatic selection of i586-alt-linux-gcc.
Checking available versions of i586-alt-linux-gcc, updating links in /etc/altern
atives ...
(You may modify the symlinks there yourself if desired - see `man ln'.)
Updating i586-alt-linux-gcc (/usr/bin/i586-alt-linux-gcc) to point to /usr/bin/i
586-alt-linux-gcc-3.2.
Leaving i586-alt-linux-gcov (/usr/bin/i586-alt-linux-gcov) pointing to /usr/bini586-alt-linux-gcov-3.2.
Leaving gcc.1.bz2 (/usr/share/man/man1/gcc.1.bz2) pointing to /usr/share/man/ma1/gcc-3.2.1.bz2.
Leaving i586-alt-linux-unprotoize (/usr/bin/i586-alt-linux-unprotoize) pointingto /usr/bin/i586-alt-linux-unprotoize-3.2.
Leaving i586-alt-linux-protoize (/usr/bin/i586-alt-linux-protoize) pointing to usr/bin/i586-alt-linux-protoize-3.2.
Leaving gcov.1.bz2 (/usr/share/man/man1/gcov.1.bz2) pointing to /usr/share/man/an1/gcov-3.2.1.bz2.

Setting up automatic selection of i586-alt-linux-g++.
Checking available versions of i586-alt-linux-g++, updating links in /etc/alteratives ...
(You may modify the symlinks there yourself if desired - see `man ln'.)
Updating i586-alt-linux-g++ (/usr/bin/i586-alt-linux-g++) to point to /usr/bin/586-alt-linux-g++-3.2.
Leaving i586-alt-linux-c++filt (/usr/bin/i586-alt-linux-c++filt) pointing to /ur/bin/i586-alt-linux-c++filt-3.2.
Leaving g++.1.bz2 (/usr/share/man/man1/g++.1.bz2) pointing to /usr/share/man/ma1/gcc-3.2.1.bz2.