[16:18] <dsmythies> apw: I made an 19.10 VM server and tried to compile the mainline there, using the exact same kernel config file. Indeed, it fails as per the Ubuntu mainline PPA. (Compiler: gcc (Ubuntu 9.1.0-6ubuntu2) 9.1.0) Which is no news for you, but for my own education.
[16:19] <apw> right the compiler has some new options enabled by default.