将GCC的评级从5.2.1降至4.9 Ubuntu 15.10

Question

由于程序兼容性问题，我需要将GCC的评级降低到至少4.9。

我该怎么做？谢谢。

编辑:该程序是Blender，并正在尝试进行GPU渲染。控制台正在排除的特定错误是

CUDA version 7.5 detected, build may succeed but only CUDA 6.5 is officially supported.
Compiling CUDA kernel ...
"/usr/local/cuda/bin/nvcc" -arch=sm_52 -m64 --cubin "/usr/share/blender/2.76/scripts/addons/cycles/kernel/kernels/cuda/kernel.cu" -o "/home/matthew/.config/blender/2.76/cache/cycles_kernel_sm52_3A157B804910758CA7C526B5EF063D78.cubin" --ptxas-options="-v" --use_fast_math -I"/usr/share/blender/2.76/scripts/addons/cycles/kernel" -DNVCC -D__KERNEL_CUDA_VERSION__=75
In file included from /usr/local/cuda/bin/../targets/x86_64-linux/include/cuda_runtime.h:76:0,
                 from <command-line>:0:
/usr/local/cuda/bin/../targets/x86_64-linux/include/host_config.h:115:2: error: #error -- unsupported GNU version! gcc versions later than 4.9 are not supported!
 #error -- unsupported GNU version! gcc versions later than 4.9 are not supporte
  ^
CUDA kernel compilation failed, see console for details.

Refer to the Cycles GPU rendering documentation for possible solutions:
http://www.blender.org/manual/render/cycles/gpu_rendering.html

Error: CUDA kernel compilation failed, see console for details.`

Answer 1

这个答案是危险的，因为它会破坏您的系统和您系统上的GCC库，并使您的系统无法使用。**在使用这个答案时要小心，并认为这是“最后的解决办法”。

卸载gcc5.4

sudo apt-get remove gcc g++

再次检查gcc：

gcc –version

安装gcc 4.9/g++ 4.9

sudo apt-get install gcc-4.9 g++-4.9

检查版本：

g++-4.9 –version

链接gcc g++

ln -s /usr/bin/g++-4.9 /usr/bin/g++
ln -s /usr/bin/gcc-4.9 /usr/bin/gcc

检查版本：

g++ –v
gcc –v

引用自这个博客和我自己的安装