This fixed my problem. I am reinstalling VirtualBox 6.1.4 and the command "sudo ln -fs gcc-8 /usr/bin/gcc" solve the problem.
-- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/1830961 Title: Kernels & kernel drivers fail to build with gcc-9 [error: ‘-mindirect- branch’ and ‘-fcf-protection’ are not compatible] To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/backport-iwlwifi-dkms/+bug/1830961/+subscriptions -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs
