升级GCC

1.

wget http://ftp.gnu.org/gnu/gcc/gcc-4.9.4/gcc-4.9.4.tar.gz

2.

tar -zxvf gcc-4.9.4.tar.gz

3.

cd gcc-4.9.4

4.

./contrib/download_prerequisites

5.

cd ..

mkdir build_gcc_4.9.4

6.

cd build_gcc_4.9.4

7.

../gcc-4.9.4/configure --enable-checking=release --enable-languages=c,c++ --disable-multilib

8.

make -j20
make install

9.

/usr/sbin/update-alternatives --install  /usr/bin/gcc gcc /usr/local/bin/x86_64-unknown-linux-gnu-gcc-4.9.4 40

/usr/sbin/update-alternatives --install /usr/bin/g++ g++ /usr/local/bin/g++ 40

10.

vi /etc/profile

export LD_LIBRARY_PATH=/usr/local/lib64:$LD_LIBRARY_PATH
export LD_RUN_PATH=/usr/local/lib64:$LD_RUN_PATH

source /etc/profile

11.

echo "/usr/local/lib64" >> /etc/ld.so.conf

12.

gcc --version

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