GLIBCXX_3.4
GLIBCXX_3.4.1
GLIBCXX_3.4.2
GLIBCXX_3.4.3
GLIBCXX_3.4.4
GLIBCXX_3.4.5
GLIBCXX_3.4.6
GLIBCXX_3.4.7
GLIBCXX_3.4.8
GLIBCXX_3.4.9
GLIBCXX_3.4.10
GLIBCXX_3.4.11
GLIBCXX_3.4.12
GLIBCXX_3.4.13
GLIBCXX_FORCE_NEW
GLIBCXX_DEBUG_MESSAGE_LENGTH

$ ls -l /usr/lib | grep libstdc++.so
lrwxrwxrwx.  1 root root       19 Dec 18  2010 libstdc++.so.6 -> libstdc++.so.6.0.14
-rwxr-xr-x   1 root root   950428 Sep 24  2010 libstdc++.so.6.0.14

$ ln -s libstdc++.so.6 libstdc++.so.6.0.15

$ ls -l /usr/lib | grep libstdc++.so
lrwxrwxrwx.  1 root root       19 Dec 18  2010 libstdc++.so.6 -> libstdc++.so.6.0.14
lrwxrwxrwx.  1 root root       19 Dec 18  2010 libstdc++.so.6.0.15 -> libstdc++.so.6.0.14
-rwxr-xr-x   1 root root   950428 Sep 24  2010 libstdc++.so.6.0.14

$ LD_PRELOAD='mylibc.so anotherlib.so' program

tar xzf gcc-4.6.2.tar.gz
cd gcc-4.6.2
./contrib/download_prerequisites
cd ..
mkdir objdir
cd objdir
$PWD/../gcc-4.6.2/configure --prefix=/opt/gcc-4.6.2
make
make install