如何在 20.04 上将 GCC 降级到版本 6？
我需要 GCC6 来编译 CUDA9 文件。
试
apt install gcc-6给我这个错误：
Package gcc-6 is not available, but is referred to by another package.
This may mean that the package is missing, has been obsoleted, or
is only available from another source
E: Package 'gcc-6' has no installation candidate