Ubuntu 23.10 fails to install VBoxLinuxadditions

Ubuntu 23.10 fails to install Virtualbox Linuxaddditions (VBox 7.0.10 on Ubuntu 22.04.3).

vboxadd-setup.log:
Building the main Guest Additions 7.0.10 module for kernel 6.5.0-9-generic.
Building the shared folder support module.
Building the graphics driver module.
Error building the module. Build output follows.
make V=1 CONFIG_MODULE_SIG= CONFIG_MODULE_SIG_ALL= -C /lib/modules/6.5.0-9-generic/build M=/tmp/vbox.0 SRCROOT=/tmp/vbox.0 -j2 modules
make[1]: warning: -j2 forced in submake: resetting jobserver mode.
warning: the compiler differs from the one used to build the kernel
The kernel was built by: x86_64-linux-gnu-gcc-13 (Ubuntu 13.2.0-4ubuntu3) 13.2.0
You are using: gcc-13 (Ubuntu 13.2.0-4ubuntu3) 13.2.0

Prereqs installed: normally gcc make would do. Not anymore. Tried also build-essentials, dkms. Same errors in log.

How to get x86_64-linux-gnu-gcc-13 (Ubuntu 13.2.0-4ubuntu3) 13.2.0?