u/FewMolasses7496

I have returned to OS development even though my other previous attempt a while back using UEFI didn't go that far, i have decided to instead develop an OS on bios because I want to learn the low level stuff. I am wondering how can i link kernel.c and boot.s together because I need to call main from kernel.c but whenever I use extern to tell the compiler that this symbol should be ignored because the linker will solve it, I can't compile it using nasm with this command "nasm -f bin boot.s -o boot.o" because flat binaries don't support external references.