$ sudo apt-get update
$ sudo apt-get install g++-4.6 gcc-4.6 -y
$ sudo update-alternatives --remove-all gcc
$ sudo update-alternatives --remove-all g++
$ sudo update-alternatives --install /usr/bin/gcc gcc /usr/bin/gcc-4.6 10
$ sudo update-alternatives --install /usr/bin/gcc gcc /usr/bin/gcc-4.2 20
$ sudo update-alternatives --install /usr/bin/g++ g++ /usr/bin/g++-4.6 10
$ sudo update-alternatives --install /usr/bin/g++ g++ /usr/bin/g++-4.2 20
$ sudo update-alternatives --install /usr/bin/cc cc /usr/bin/gcc 30
$ sudo update-alternatives --set cc /usr/bin/gcc
$ sudo update-alternatives --install /usr/bin/c++ c++ /usr/bin/g++ 30
$ sudo update-alternatives --set c++ /usr/bin/g++
$ sudo update-alternatives --config gcc
$ sudo update-alternatives --config g++
GCC, the GNU Compiler Collection
The GNU Compiler Collection includes front ends
for C, C++, Objective-C, Fortran, Ada, Go, and D,
as well as libraries for these languages (libstdc++)
GCC was originally written as the compiler for the GNU operating system.
The GNU system was developed to be 100% free software,
free in the sense that it respects the user's freedom.
We strive to provide regular,
high quality releases,
which we want to work well on a variety of native and cross targets
(including GNU/Linux)
and encourage everyone to contribute changes or help testing GCC.
Our sources are readily and freely available via Git and weekly snapshots.
Major decisions about GCC are made by the steering committee,
guided by the mission statement.
Please note that the following documentation refers to current development.
Some information may not be applicable to any existing release.
User-Level Documentation
GCC Installation Instructions
GCC Manual
(also in PDF or PostScript or an HTML tarball)
GNU Fortran Manual
(also in PDF or PostScript or an HTML tarball)
CPP Manual
(also in PDF or PostScript or an HTML tarball)
GNAT Reference Manual
(also in PDF or PostScript or an HTML tarball)
GNAT User's Guide for Native Platforms / Unix and Windows
(also in PDF or PostScript or an HTML tarball)
GCCGO Manual
(also in PDF or PostScript or an HTML tarball)
GNU D Manual
(also in PDF or PostScript or an HTML tarball)
GNU M2 Manual
(also in PDF or PostScript or an HTML tarball)
GNU Offloading and Multi Processing Runtime Library Manual
(also in PDF or PostScript or an HTML tarball)
libstdc++-v3 Documentation
GCC Quad-Precision Math Library Manual
(also in PDF or PostScript or an HTML tarball)
libgccjit documentation
Texinfo sources of all the manuals
Internals Documentation
GCC Internals Manual
(also in PDF or PostScript or an HTML tarball)
CPP Internals Manual
(also in PDF or PostScript or an HTML tarball)
GNU Fortran Internals Manual
(also in PDF or PostScript or an HTML tarball)
GNAT Coding Style Manual (also in PDF or PostScript or an HTML tarball)
Libiberty Manual
(also in PDF or PostScript or an HTML tarball)
For questions related to the use of GCC,
please consult these web pages and the GCC manuals.
If that fails,
the gcc-help@gcc.gnu.org
mailing list might help.
Comments on these web pages and the development of GCC
are welcome on our developer list at gcc@gcc.gnu.org.
All of our lists have public archives.
Copyright (C) Free Software Foundation, Inc.
Verbatim copying and distribution
of this entire article is permitted in any medium,
provided this notice is preserved.
These pages are maintained by the GCC team.
how-to-choose-the-default-gcc-and-g-version
