Just to do things in the right way…

CFLAGS := -fno-stack-protector -fno-builtin -nostdinc -O -g -Wall -I.
CC := g++
AC := as
LD := ld
all: kernel.bin
kernel.bin: kernel_loader.o kernel.o kernel_video.o
$(LD) -T kernel_linker.ld -o kernel.bin kernel_loader.o kernel.o kernel_video.o
@echo Done!
kernel_loader.o: kernel_loader.s
$(AC) -o kernel_loader.o kernel_loader.s
main.o: kernel.c
$(CC) $(CFLAGS) -c -o kernel.o kernel.c
kernel_video.o: kernel_video.c
$(CC) $(CFLAGS) -c -o kernel_video.o kernel_video.c
clean:
rm -f *.o *.bin