Change Ubuntu gcc, g++ default compiler version

Method One:

First, take a look at what versions of GCC you have installed in your Ubuntu command: ls/usr/bin/gcc*-L My display is

lrwxrwxrwx 1 root root 7 2011-08-14 15:17/USR/BIN/GCC-gcc-4.6

-rwxr-xr-x 1 root root 224544 2011-10-06 05:47/usr/bin/gcc-4.4

-rwxr-xr-x 1 root root 237072 2011-09-17 17:25/usr/bin/gcc-4.5

-rwxr-xr-x 1 root root 302104 2011-09-17 05:43/usr/bin/gcc-4.6

As shown above, you can see that the default installation is gcc-4.6, which is now changed to gcc-4.4

Delete the gcc-4.6 soft connection file/USR/BIN/GCC. (just remove the soft connection)

Command: sudo rm/usr/bin/gcc

Then build a soft connection that points to the gcc-4.4.

Command: sudo ln-s/USR/BIN/GCC-4.4/USR/BIN/GCC

OK, www.linuxidc.com now with the command: Gcc-v display as follows:

Use built-in specs.

Target: I686-linux-gnu

Configured as:.. /src/configure-v--with-pkgversion= ' Ubuntu/linaro 4.4.6-11ubuntu2 '--with-bugurl=file:///usr/share/doc/gcc-4.4/ Readme. Bugs--enable-languages=c,c++,fortran,objc,obj-c++--prefix=/usr--program-suffix=-4.4--enable-shared-- Enable-linker-build-id--with-system-zlib--libexecdir=/usr/lib--without-included-gettext--enable-threads=posix- -with-gxx-include-dir=/usr/include/c++/4.4--libdir=/usr/lib--enable-nls--with-sysroot=/--enable-clocale=gnu-- Enable-libstdcxx-debug--enable-objc-gc--enable-targets=all--disable-werror--with-arch-32=i686--with-tune= Generic--enable-checking=release--build=i686-linux-gnu--host=i686-linux-gnu--target=i686-linux-gnu

Threading Model: POSIX

GCC version 4.4.6 (Ubuntu/linaro 4.4.6-11ubuntu2)

Change the default version of g++ in the same way.

Method Two:

Modify the default GCC and g++ versions of 4.4

sudo update-alternatives--remove-all gcc

sudo update-alternatives--INSTALL/USR/BIN/GCC gcc/usr/bin/gcc-4.4 40

sudo update-alternatives--install/usr/bin/g++ g++/usr/bin/g++-4.4 40

Configuring the default GCC and g++

sudo update-alternatives--config gcc

sudo update-alternatives--config g++

Change Ubuntu gcc, g++ default compiler version